cargo: update dependencies

Last of the functions that need to be ported over to strided-ndarray.

.clang-format

@@ -0,0 +1,32 @@
+BasedOnStyle: LLVM
+
+Language: Cpp
+Standard: Cpp11
+
+AccessModifierOffset: -1
+AlignEscapedNewlines: Left
+AlwaysBreakAfterReturnType: None
+AlwaysBreakTemplateDeclarations: Yes
+AllowAllParametersOfDeclarationOnNextLine: false
+AllowShortFunctionsOnASingleLine: Inline
+BinPackParameters: false
+BreakBeforeBinaryOperators: NonAssignment
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializers: AfterColon
+BreakInheritanceList: AfterColon
+ColumnLimit: 120
+ConstructorInitializerAllOnOneLineOrOnePerLine: true
+ContinuationIndentWidth: 4
+DerivePointerAlignment: false
+IndentCaseLabels: true
+IndentPPDirectives: None
+IndentWidth: 4
+MaxEmptyLinesToKeep: 1
+PointerAlignment: Left
+ReflowComments: true
+SortIncludes: false
+SortUsingDeclarations: true
+SpaceAfterTemplateKeyword: false
+SpacesBeforeTrailingComments: 2
+TabWidth: 4
+UseTab: Never

.pre-commit-config.yaml

@@ -1,24 +1,24 @@
 # See https://pre-commit.com for more information
 # See https://pre-commit.com/hooks.html for more hooks
 
-default_stages: [commit]
+default_stages: [pre-commit]
 
 repos:
   - repo: local
     hooks:
       - id: nac3-cargo-fmt
         name: nac3 cargo format
-        entry: cargo
+        entry: nix
         language: system
         types: [file, rust]
         pass_filenames: false
         description: Runs cargo fmt on the codebase.
-        args: [fmt]
+        args: [develop, -c, cargo, fmt, --all]
       - id: nac3-cargo-clippy
         name: nac3 cargo clippy
-        entry: cargo
+        entry: nix
         language: system
         types: [file, rust]
         pass_filenames: false
         description: Runs cargo clippy on the codebase.
-        args: [clippy, --tests]
+        args: [develop, -c, cargo, clippy, --tests]

Cargo.toml

@@ -4,6 +4,7 @@ members = [
   "nac3ast",
   "nac3parser",
   "nac3core",
+  "nac3core/nac3core_derive",
   "nac3standalone",
   "nac3artiq",
   "runkernel",

flake.lock

@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1723637854,
+        "lastModified": 1733940404,
-        "narHash": "sha256-med8+5DSWa2UnOqtdICndjDAEjxr5D7zaIiK4pn0Q7c=",
+        "narHash": "sha256-Pj39hSoUA86ZePPF/UXiYHHM7hMIkios8TYG29kQT4g=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "c3aa7b8938b17aebd2deecf7be0636000d62a2b9",
+        "rev": "5d67ea6b4b63378b9c13be21e2ec9d1afc921713",
         "type": "github"
       },
       "original": {

flake.nix

@@ -107,18 +107,18 @@
             (pkgs.fetchFromGitHub {
               owner = "m-labs";
               repo = "sipyco";
-              rev = "939f84f9b5eef7efbf7423c735d1834783b6140e";
+              rev = "094a6cd63ffa980ef63698920170e50dc9ba77fd";
-              sha256 = "sha256-15Nun4EY35j+6SPZkjzZtyH/ncxLS60KuGJjFh5kSTc=";
+              sha256 = "sha256-PPnAyDedUQ7Og/Cby9x5OT9wMkNGTP8GS53V6N/dk4w=";
             })
             (pkgs.fetchFromGitHub {
               owner = "m-labs";
               repo = "artiq";
-              rev = "923ca3377d42c815f979983134ec549dc39d3ca0";
+              rev = "28c9de3e251daa89a8c9fd79d5ab64a3ec03bac6";
-              sha256 = "sha256-oJoEeNEeNFSUyh6jXG8Tzp6qHVikeHS0CzfE+mODPgw=";
+              sha256 = "sha256-vAvpbHc5B+1wtG8zqN7j9dQE1ON+i22v+uqA+tw6Gak=";
             })
           ];
           buildInputs = [
-            (python3-mimalloc.withPackages(ps: [ ps.numpy ps.scipy ps.jsonschema ps.lmdb nac3artiq-instrumented ]))
+            (python3-mimalloc.withPackages(ps: [ ps.numpy ps.scipy ps.jsonschema ps.lmdb ps.platformdirs nac3artiq-instrumented ]))
             pkgs.llvmPackages_14.llvm.out
           ];
           phases = [ "buildPhase" "installPhase" ];

nac3artiq/Cargo.toml

@@ -12,16 +12,10 @@ crate-type = ["cdylib"]
 itertools = "0.13"
 pyo3 = { version = "0.21", features = ["extension-module", "gil-refs"] }
 parking_lot = "0.12"
-tempfile = "3.10"
+tempfile = "3.13"
-nac3parser = { path = "../nac3parser" }
 nac3core = { path = "../nac3core" }
 nac3ld = { path = "../nac3ld" }
 
-[dependencies.inkwell]
-version = "0.4"
-default-features = false
-features = ["llvm14-0", "target-x86", "target-arm", "target-riscv", "no-libffi-linking"]
-
 [features]
 init-llvm-profile = []
 no-escape-analysis = ["nac3core/no-escape-analysis"]

nac3artiq/demo/embedding_map.py

@@ -7,33 +7,6 @@ class EmbeddingMap:
         self.function_map = {}
         self.attributes_writeback = []
 
-        # preallocate exception names
-        self.preallocate_runtime_exception_names(["RuntimeError",
-                                          "RTIOUnderflow",
-                                          "RTIOOverflow",
-                                          "RTIODestinationUnreachable",
-                                          "DMAError",
-                                          "I2CError",
-                                          "CacheError",
-                                          "SPIError",
-                                          "0:ZeroDivisionError",
-                                          "0:IndexError",
-                                          "0:ValueError",
-                                          "0:RuntimeError",
-                                          "0:AssertionError",
-                                          "0:KeyError",
-                                          "0:NotImplementedError",
-                                          "0:OverflowError",
-                                          "0:IOError",
-                                          "0:UnwrapNoneError"])
-
-    def preallocate_runtime_exception_names(self, names):
-        for i, name in enumerate(names):
-            if ":" not in name:
-                name = "0:artiq.coredevice.exceptions." + name
-            exn_id = self.store_str(name)
-            assert exn_id == i
-
     def store_function(self, key, fun):
         self.function_map[key] = fun
         return key

nac3artiq/demo/min_artiq.py

@@ -112,10 +112,15 @@ def extern(function):
     register_function(function)
     return function
 
-def rpc(function):
+
-    """Decorates a function declaration defined by the core device runtime."""
+def rpc(arg=None, flags={}):
-    register_function(function)
+    """Decorates a function or method to be executed on the host interpreter."""
-    return function
+    if arg is None:
+        def inner_decorator(function):
+            return rpc(function, flags)
+        return inner_decorator
+    register_function(arg)
+    return arg
 
 def kernel(function_or_method):
     """Decorates a function or method to be executed on the core device."""
@@ -201,7 +206,7 @@ class Core:
         embedding = EmbeddingMap()
 
         if allow_registration:
-            compiler.analyze(registered_functions, registered_classes)
+            compiler.analyze(registered_functions, registered_classes, set())
             allow_registration = False
 
         if hasattr(method, "__self__"):

nac3artiq/src/codegen.rs

@@ -1,38 +1,3 @@
-use nac3core::{
-    codegen::{
-        classes::{
-            ArrayLikeIndexer, ArrayLikeValue, ArraySliceValue, ListValue, NDArrayType,
-            NDArrayValue, RangeValue, UntypedArrayLikeAccessor,
-        },
-        expr::{destructure_range, gen_call},
-        irrt::call_ndarray_calc_size,
-        llvm_intrinsics::{call_int_smax, call_memcpy_generic, call_stackrestore, call_stacksave},
-        stmt::{gen_block, gen_for_callback_incrementing, gen_if_callback, gen_with},
-        CodeGenContext, CodeGenerator,
-    },
-    symbol_resolver::ValueEnum,
-    toplevel::{helper::PrimDef, numpy::unpack_ndarray_var_tys, DefinitionId, GenCall},
-    typecheck::typedef::{iter_type_vars, FunSignature, FuncArg, Type, TypeEnum, VarMap},
-};
-
-use nac3parser::ast::{Expr, ExprKind, Located, Stmt, StmtKind, StrRef};
-
-use inkwell::{
-    context::Context,
-    module::Linkage,
-    types::{BasicType, IntType},
-    values::{BasicValueEnum, PointerValue, StructValue},
-    AddressSpace, IntPredicate,
-};
-
-use pyo3::{
-    types::{PyDict, PyList},
-    PyObject, PyResult, Python,
-};
-
-use crate::{symbol_resolver::InnerResolver, timeline::TimeFns};
-
-use itertools::Itertools;
 use std::{
     collections::{hash_map::DefaultHasher, HashMap},
     hash::{Hash, Hasher},
@@ -41,6 +6,43 @@ use std::{
     sync::Arc,
 };
 
+use itertools::Itertools;
+use pyo3::{
+    types::{PyDict, PyList},
+    PyObject, PyResult, Python,
+};
+
+use super::{symbol_resolver::InnerResolver, timeline::TimeFns};
+use nac3core::{
+    codegen::{
+        expr::{destructure_range, gen_call},
+        llvm_intrinsics::{call_int_smax, call_memcpy, call_stackrestore, call_stacksave},
+        stmt::{gen_block, gen_for_callback_incrementing, gen_if_callback, gen_with},
+        type_aligned_alloca,
+        types::ndarray::NDArrayType,
+        values::{
+            ArrayLikeIndexer, ArrayLikeValue, ArraySliceValue, ListValue, ProxyValue, RangeValue,
+            UntypedArrayLikeAccessor,
+        },
+        CodeGenContext, CodeGenerator,
+    },
+    inkwell::{
+        context::Context,
+        module::Linkage,
+        types::{BasicType, IntType},
+        values::{BasicValueEnum, IntValue, PointerValue, StructValue},
+        AddressSpace, IntPredicate, OptimizationLevel,
+    },
+    nac3parser::ast::{Expr, ExprKind, Located, Stmt, StmtKind, StrRef},
+    symbol_resolver::ValueEnum,
+    toplevel::{
+        helper::{extract_ndims, PrimDef},
+        numpy::unpack_ndarray_var_tys,
+        DefinitionId, GenCall,
+    },
+    typecheck::typedef::{iter_type_vars, FunSignature, FuncArg, Type, TypeEnum, VarMap},
+};
+
 /// The parallelism mode within a block.
 #[derive(Copy, Clone, Eq, PartialEq)]
 enum ParallelMode {
@@ -459,55 +461,49 @@ fn format_rpc_arg<'ctx>(
             let llvm_i1 = ctx.ctx.bool_type();
             let llvm_usize = generator.get_size_type(ctx.ctx);
 
-            let (elem_ty, _) = unpack_ndarray_var_tys(&mut ctx.unifier, arg_ty);
+            let (elem_ty, ndims) = unpack_ndarray_var_tys(&mut ctx.unifier, arg_ty);
-            let llvm_arg_ty =
+            let ndims = extract_ndims(&ctx.unifier, ndims);
-                NDArrayType::new(generator, ctx.ctx, ctx.get_llvm_type(generator, elem_ty));
+            let dtype = ctx.get_llvm_type(generator, elem_ty);
-            let llvm_arg = NDArrayValue::from_ptr_val(arg.into_pointer_value(), llvm_usize, None);
+            let ndarray = NDArrayType::new(generator, ctx.ctx, dtype, Some(ndims))
+                .map_value(arg.into_pointer_value(), None);
 
-            let llvm_usize_sizeof = ctx
+            let ndims = llvm_usize.const_int(ndims, false);
-                .builder
-                .build_int_truncate_or_bit_cast(llvm_arg_ty.size_type().size_of(), llvm_usize, "")
-                .unwrap();
-            let llvm_pdata_sizeof = ctx
-                .builder
-                .build_int_truncate_or_bit_cast(
-                    llvm_arg_ty.element_type().ptr_type(AddressSpace::default()).size_of(),
-                    llvm_usize,
-                    "",
-                )
-                .unwrap();
 
-            let dims_buf_sz =
+            // `ndarray.data` is possibly not contiguous, and we need it to be contiguous for
-                ctx.builder.build_int_mul(llvm_arg.load_ndims(ctx), llvm_usize_sizeof, "").unwrap();
+            // the reader.
+            // Turning it into a ContiguousNDArray to get a `data` that is contiguous.
+            let carray = ndarray.make_contiguous_ndarray(generator, ctx);
 
-            let buffer_size =
+            let sizeof_usize = llvm_usize.size_of();
-                ctx.builder.build_int_add(dims_buf_sz, llvm_pdata_sizeof, "").unwrap();
+            let sizeof_usize =
+                ctx.builder.build_int_z_extend_or_bit_cast(sizeof_usize, llvm_usize, "").unwrap();
 
-            let buffer = ctx.builder.build_array_alloca(llvm_i8, buffer_size, "rpc.arg").unwrap();
+            let sizeof_pdata = dtype.ptr_type(AddressSpace::default()).size_of();
-            let buffer = ArraySliceValue::from_ptr_val(buffer, buffer_size, Some("rpc.arg"));
+            let sizeof_pdata =
+                ctx.builder.build_int_z_extend_or_bit_cast(sizeof_pdata, llvm_usize, "").unwrap();
 
-            let ppdata = generator.gen_var_alloc(ctx, llvm_arg_ty.element_type(), None).unwrap();
+            let sizeof_buf_shape = ctx.builder.build_int_mul(sizeof_usize, ndims, "").unwrap();
-            ctx.builder.build_store(ppdata, llvm_arg.data().base_ptr(ctx, generator)).unwrap();
+            let sizeof_buf = ctx.builder.build_int_add(sizeof_buf_shape, sizeof_pdata, "").unwrap();
 
-            call_memcpy_generic(
+            // buf = { data: void*, shape: [size_t; ndims]; }
-                ctx,
+            let buf = ctx.builder.build_array_alloca(llvm_i8, sizeof_buf, "rpc.arg").unwrap();
-                buffer.base_ptr(ctx, generator),
+            let buf = ArraySliceValue::from_ptr_val(buf, sizeof_buf, Some("rpc.arg"));
-                ppdata,
+            let buf_data = buf.base_ptr(ctx, generator);
-                llvm_pdata_sizeof,
+            let buf_shape =
-                llvm_i1.const_zero(),
+                unsafe { buf.ptr_offset_unchecked(ctx, generator, &sizeof_pdata, None) };
-            );
 
-            let pbuffer_dims_begin =
+            // Write to `buf->data`
-                unsafe { buffer.ptr_offset_unchecked(ctx, generator, &llvm_pdata_sizeof, None) };
+            let carray_data = carray.load_data(ctx);
-            call_memcpy_generic(
+            let carray_data = ctx.builder.build_pointer_cast(carray_data, llvm_pi8, "").unwrap();
-                ctx,
+            call_memcpy(ctx, buf_data, carray_data, sizeof_pdata, llvm_i1.const_zero());
-                pbuffer_dims_begin,
-                llvm_arg.dim_sizes().base_ptr(ctx, generator),
-                dims_buf_sz,
-                llvm_i1.const_zero(),
-            );
 
-            buffer.base_ptr(ctx, generator)
+            // Write to `buf->shape`
+            let carray_shape = ndarray.shape().base_ptr(ctx, generator);
+            let carray_shape_i8 =
+                ctx.builder.build_pointer_cast(carray_shape, llvm_pi8, "").unwrap();
+            call_memcpy(ctx, buf_shape, carray_shape_i8, sizeof_buf_shape, llvm_i1.const_zero());
+
+            buf.base_ptr(ctx, generator)
         }
 
         _ => {
@@ -517,7 +513,7 @@ fn format_rpc_arg<'ctx>(
             ctx.builder.build_store(arg_slot, arg).unwrap();
 
             ctx.builder
-                .build_bitcast(arg_slot, llvm_pi8, "rpc.arg")
+                .build_bit_cast(arg_slot, llvm_pi8, "rpc.arg")
                 .map(BasicValueEnum::into_pointer_value)
                 .unwrap()
         }
@@ -528,12 +524,276 @@ fn format_rpc_arg<'ctx>(
     arg_slot
 }
 
+/// Formats an RPC return value to conform to the expected format required by NAC3.
+fn format_rpc_ret<'ctx>(
+    generator: &mut dyn CodeGenerator,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ret_ty: Type,
+) -> Option<BasicValueEnum<'ctx>> {
+    // -- receive value:
+    // T result = {
+    //   void *ret_ptr = alloca(sizeof(T));
+    //   void *ptr = ret_ptr;
+    //   loop: int size = rpc_recv(ptr);
+    //   // Non-zero: Provide `size` bytes of extra storage for variable-length data.
+    //   if(size) { ptr = alloca(size); goto loop; }
+    //   else *(T*)ret_ptr
+    // }
+
+    let llvm_i8 = ctx.ctx.i8_type();
+    let llvm_i32 = ctx.ctx.i32_type();
+    let llvm_i8_8 = ctx.ctx.struct_type(&[llvm_i8.array_type(8).into()], false);
+    let llvm_pi8 = llvm_i8.ptr_type(AddressSpace::default());
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let rpc_recv = ctx.module.get_function("rpc_recv").unwrap_or_else(|| {
+        ctx.module.add_function("rpc_recv", llvm_i32.fn_type(&[llvm_pi8.into()], false), None)
+    });
+
+    if ctx.unifier.unioned(ret_ty, ctx.primitives.none) {
+        ctx.build_call_or_invoke(rpc_recv, &[llvm_pi8.const_null().into()], "rpc_recv");
+        return None;
+    }
+
+    let prehead_bb = ctx.builder.get_insert_block().unwrap();
+    let current_function = prehead_bb.get_parent().unwrap();
+    let head_bb = ctx.ctx.append_basic_block(current_function, "rpc.head");
+    let alloc_bb = ctx.ctx.append_basic_block(current_function, "rpc.continue");
+    let tail_bb = ctx.ctx.append_basic_block(current_function, "rpc.tail");
+
+    let llvm_ret_ty = ctx.get_llvm_abi_type(generator, ret_ty);
+
+    let result = match &*ctx.unifier.get_ty_immutable(ret_ty) {
+        TypeEnum::TObj { obj_id, .. } if *obj_id == PrimDef::NDArray.id() => {
+            let num_0 = llvm_usize.const_zero();
+
+            // Round `val` up to its modulo `power_of_two`
+            let round_up = |ctx: &mut CodeGenContext<'ctx, '_>,
+                            val: IntValue<'ctx>,
+                            power_of_two: IntValue<'ctx>| {
+                debug_assert_eq!(
+                    val.get_type().get_bit_width(),
+                    power_of_two.get_type().get_bit_width()
+                );
+
+                let llvm_val_t = val.get_type();
+
+                let max_rem = ctx
+                    .builder
+                    .build_int_sub(power_of_two, llvm_val_t.const_int(1, false), "")
+                    .unwrap();
+                ctx.builder
+                    .build_and(
+                        ctx.builder.build_int_add(val, max_rem, "").unwrap(),
+                        ctx.builder.build_not(max_rem, "").unwrap(),
+                        "",
+                    )
+                    .unwrap()
+            };
+
+            // Allocate the resulting ndarray
+            // A condition after format_rpc_ret ensures this will not be popped this off.
+            let (dtype, ndims) = unpack_ndarray_var_tys(&mut ctx.unifier, ret_ty);
+            let dtype_llvm = ctx.get_llvm_type(generator, dtype);
+            let ndims = extract_ndims(&ctx.unifier, ndims);
+            let ndarray = NDArrayType::new(generator, ctx.ctx, dtype_llvm, Some(ndims))
+                .construct_uninitialized(generator, ctx, None);
+
+            // NOTE: Current content of `ndarray`:
+            //   - * `data` - **NOT YET** allocated.
+            //   - * `itemsize` - initialized to be size_of(dtype).
+            //   - * `ndims` - initialized.
+            //   - * `shape` - allocated; has uninitialized values.
+            //   - * `strides` - allocated; has uninitialized values.
+
+            let itemsize = ndarray.load_itemsize(ctx); // Same as doing a `ctx.get_llvm_type` on `dtype` and get its `size_of()`.
+
+            // Allocates a buffer for the initial RPC'ed object, which is guaranteed to be
+            // (4 + 4 * ndims) bytes with 8-byte alignment
+            let sizeof_usize = llvm_usize.size_of();
+            let sizeof_usize =
+                ctx.builder.build_int_truncate_or_bit_cast(sizeof_usize, llvm_usize, "").unwrap();
+
+            let sizeof_ptr = llvm_i8.ptr_type(AddressSpace::default()).size_of();
+            let sizeof_ptr =
+                ctx.builder.build_int_z_extend_or_bit_cast(sizeof_ptr, llvm_usize, "").unwrap();
+
+            let sizeof_shape =
+                ctx.builder.build_int_mul(ndarray.load_ndims(ctx), sizeof_usize, "").unwrap();
+
+            // Size of the buffer for the initial `rpc_recv()`.
+            let unaligned_buffer_size =
+                ctx.builder.build_int_add(sizeof_ptr, sizeof_shape, "").unwrap();
+
+            let stackptr = call_stacksave(ctx, None);
+            let buffer = type_aligned_alloca(
+                generator,
+                ctx,
+                llvm_i8_8,
+                unaligned_buffer_size,
+                Some("rpc.buffer"),
+            );
+            let buffer = ArraySliceValue::from_ptr_val(buffer, unaligned_buffer_size, None);
+
+            // The first call to `rpc_recv` reads the top-level ndarray object: [pdata, shape]
+            //
+            // The returned value is the number of bytes for `ndarray.data`.
+            let ndarray_nbytes = ctx
+                .build_call_or_invoke(
+                    rpc_recv,
+                    &[buffer.base_ptr(ctx, generator).into()], // Reads [usize; ndims]
+                    "rpc.size.next",
+                )
+                .map(BasicValueEnum::into_int_value)
+                .unwrap();
+
+            // debug_assert(ndarray_nbytes > 0)
+            if ctx.registry.llvm_options.opt_level == OptimizationLevel::None {
+                let cmp = ctx
+                    .builder
+                    .build_int_compare(IntPredicate::UGT, ndarray_nbytes, num_0, "")
+                    .unwrap();
+
+                ctx.make_assert(
+                    generator,
+                    cmp,
+                    "0:AssertionError",
+                    "Unexpected RPC termination for ndarray - Expected data buffer next",
+                    [None, None, None],
+                    ctx.current_loc,
+                );
+            }
+
+            // Copy shape from the buffer to `ndarray.shape`.
+            // We need to skip the first `sizeof(uint8_t*)` bytes to skip the `pdata` in `[pdata, shape]`.
+            let pbuffer_shape =
+                unsafe { buffer.ptr_offset_unchecked(ctx, generator, &sizeof_ptr, None) };
+            let pbuffer_shape =
+                ctx.builder.build_pointer_cast(pbuffer_shape, llvm_pusize, "").unwrap();
+
+            // Copy shape from buffer to `ndarray.shape`
+            ndarray.copy_shape_from_array(generator, ctx, pbuffer_shape);
+
+            // Restore stack from before allocation of buffer
+            call_stackrestore(ctx, stackptr);
+
+            // Allocate `ndarray.data`.
+            // `ndarray.shape` must be initialized beforehand in this implementation
+            //   (for ndarray.create_data() to know how many elements to allocate)
+            unsafe { ndarray.create_data(generator, ctx) }; // NOTE: the strides of `ndarray` has also been set to contiguous in `create_data`.
+
+            // debug_assert(nelems * sizeof(T) >= ndarray_nbytes)
+            if ctx.registry.llvm_options.opt_level == OptimizationLevel::None {
+                let num_elements = ndarray.size(generator, ctx);
+
+                let expected_ndarray_nbytes =
+                    ctx.builder.build_int_mul(num_elements, itemsize, "").unwrap();
+                let cmp = ctx
+                    .builder
+                    .build_int_compare(
+                        IntPredicate::UGE,
+                        expected_ndarray_nbytes,
+                        ndarray_nbytes,
+                        "",
+                    )
+                    .unwrap();
+
+                ctx.make_assert(
+                    generator,
+                    cmp,
+                    "0:AssertionError",
+                    "Unexpected allocation size request for ndarray data - Expected up to {0} bytes, got {1} bytes",
+                    [Some(expected_ndarray_nbytes), Some(ndarray_nbytes), None],
+                    ctx.current_loc,
+                );
+            }
+
+            let ndarray_data = ndarray.data().base_ptr(ctx, generator);
+
+            // NOTE: Currently on `prehead_bb`
+            ctx.builder.build_unconditional_branch(head_bb).unwrap();
+
+            // Inserting into `head_bb`. Do `rpc_recv` for `data` recursively.
+            ctx.builder.position_at_end(head_bb);
+
+            let phi = ctx.builder.build_phi(llvm_pi8, "rpc.ptr").unwrap();
+            phi.add_incoming(&[(&ndarray_data, prehead_bb)]);
+
+            let alloc_size = ctx
+                .build_call_or_invoke(rpc_recv, &[phi.as_basic_value()], "rpc.size.next")
+                .map(BasicValueEnum::into_int_value)
+                .unwrap();
+
+            let is_done = ctx
+                .builder
+                .build_int_compare(IntPredicate::EQ, llvm_i32.const_zero(), alloc_size, "rpc.done")
+                .unwrap();
+            ctx.builder.build_conditional_branch(is_done, tail_bb, alloc_bb).unwrap();
+
+            ctx.builder.position_at_end(alloc_bb);
+            // Align the allocation to sizeof(T)
+            let alloc_size = round_up(ctx, alloc_size, itemsize);
+            // TODO(Derppening): Candidate for refactor into type_aligned_alloca
+            let alloc_ptr = ctx
+                .builder
+                .build_array_alloca(
+                    dtype_llvm,
+                    ctx.builder.build_int_unsigned_div(alloc_size, itemsize, "").unwrap(),
+                    "rpc.alloc",
+                )
+                .unwrap();
+            let alloc_ptr =
+                ctx.builder.build_pointer_cast(alloc_ptr, llvm_pi8, "rpc.alloc.ptr").unwrap();
+            phi.add_incoming(&[(&alloc_ptr, alloc_bb)]);
+            ctx.builder.build_unconditional_branch(head_bb).unwrap();
+
+            ctx.builder.position_at_end(tail_bb);
+            ndarray.as_base_value().into()
+        }
+
+        _ => {
+            let slot = ctx.builder.build_alloca(llvm_ret_ty, "rpc.ret.slot").unwrap();
+            let slotgen = ctx.builder.build_bit_cast(slot, llvm_pi8, "rpc.ret.ptr").unwrap();
+            ctx.builder.build_unconditional_branch(head_bb).unwrap();
+            ctx.builder.position_at_end(head_bb);
+
+            let phi = ctx.builder.build_phi(llvm_pi8, "rpc.ptr").unwrap();
+            phi.add_incoming(&[(&slotgen, prehead_bb)]);
+            let alloc_size = ctx
+                .build_call_or_invoke(rpc_recv, &[phi.as_basic_value()], "rpc.size.next")
+                .unwrap()
+                .into_int_value();
+            let is_done = ctx
+                .builder
+                .build_int_compare(IntPredicate::EQ, llvm_i32.const_zero(), alloc_size, "rpc.done")
+                .unwrap();
+
+            ctx.builder.build_conditional_branch(is_done, tail_bb, alloc_bb).unwrap();
+            ctx.builder.position_at_end(alloc_bb);
+
+            let alloc_ptr =
+                ctx.builder.build_array_alloca(llvm_pi8, alloc_size, "rpc.alloc").unwrap();
+            let alloc_ptr =
+                ctx.builder.build_bit_cast(alloc_ptr, llvm_pi8, "rpc.alloc.ptr").unwrap();
+            phi.add_incoming(&[(&alloc_ptr, alloc_bb)]);
+            ctx.builder.build_unconditional_branch(head_bb).unwrap();
+
+            ctx.builder.position_at_end(tail_bb);
+            ctx.builder.build_load(slot, "rpc.result").unwrap()
+        }
+    };
+
+    Some(result)
+}
+
 fn rpc_codegen_callback_fn<'ctx>(
     ctx: &mut CodeGenContext<'ctx, '_>,
     obj: Option<(Type, ValueEnum<'ctx>)>,
     fun: (&FunSignature, DefinitionId),
     args: Vec<(Option<StrRef>, ValueEnum<'ctx>)>,
     generator: &mut dyn CodeGenerator,
+    is_async: bool,
 ) -> Result<Option<BasicValueEnum<'ctx>>, String> {
     let int8 = ctx.ctx.i8_type();
     let int32 = ctx.ctx.i32_type();
@@ -642,91 +902,72 @@ fn rpc_codegen_callback_fn<'ctx>(
     }
 
     // call
-    let rpc_send = ctx.module.get_function("rpc_send").unwrap_or_else(|| {
+    if is_async {
-        ctx.module.add_function(
+        let rpc_send_async = ctx.module.get_function("rpc_send_async").unwrap_or_else(|| {
-            "rpc_send",
+            ctx.module.add_function(
-            ctx.ctx.void_type().fn_type(
+                "rpc_send_async",
-                &[
+                ctx.ctx.void_type().fn_type(
-                    int32.into(),
+                    &[
-                    tag_ptr_type.ptr_type(AddressSpace::default()).into(),
+                        int32.into(),
-                    ptr_type.ptr_type(AddressSpace::default()).into(),
+                        tag_ptr_type.ptr_type(AddressSpace::default()).into(),
-                ],
+                        ptr_type.ptr_type(AddressSpace::default()).into(),
-                false,
+                    ],
-            ),
+                    false,
-            None,
+                ),
-        )
+                None,
-    });
+            )
-    ctx.builder
+        });
-        .build_call(rpc_send, &[service_id.into(), tag_ptr.into(), args_ptr.into()], "rpc.send")
+        ctx.builder
-        .unwrap();
+            .build_call(
+                rpc_send_async,
+                &[service_id.into(), tag_ptr.into(), args_ptr.into()],
+                "rpc.send",
+            )
+            .unwrap();
+    } else {
+        let rpc_send = ctx.module.get_function("rpc_send").unwrap_or_else(|| {
+            ctx.module.add_function(
+                "rpc_send",
+                ctx.ctx.void_type().fn_type(
+                    &[
+                        int32.into(),
+                        tag_ptr_type.ptr_type(AddressSpace::default()).into(),
+                        ptr_type.ptr_type(AddressSpace::default()).into(),
+                    ],
+                    false,
+                ),
+                None,
+            )
+        });
+        ctx.builder
+            .build_call(rpc_send, &[service_id.into(), tag_ptr.into(), args_ptr.into()], "rpc.send")
+            .unwrap();
+    }
 
     // reclaim stack space used by arguments
     call_stackrestore(ctx, stackptr);
 
-    // -- receive value:
+    if is_async {
-    // T result = {
+        // async RPCs do not return any values
-    //   void *ret_ptr = alloca(sizeof(T));
+        Ok(None)
-    //   void *ptr = ret_ptr;
+    } else {
-    //   loop: int size = rpc_recv(ptr);
+        let result = format_rpc_ret(generator, ctx, fun.0.ret);
-    //   // Non-zero: Provide `size` bytes of extra storage for variable-length data.
-    //   if(size) { ptr = alloca(size); goto loop; }
-    //   else *(T*)ret_ptr
-    // }
-    let rpc_recv = ctx.module.get_function("rpc_recv").unwrap_or_else(|| {
-        ctx.module.add_function("rpc_recv", int32.fn_type(&[ptr_type.into()], false), None)
-    });
 
-    if ctx.unifier.unioned(fun.0.ret, ctx.primitives.none) {
+        if !result.is_some_and(|res| res.get_type().is_pointer_type()) {
-        ctx.build_call_or_invoke(rpc_recv, &[ptr_type.const_null().into()], "rpc_recv");
+            // An RPC returning an NDArray would not touch here.
-        return Ok(None);
+            call_stackrestore(ctx, stackptr);
+        }
+
+        Ok(result)
     }
-
-    let prehead_bb = ctx.builder.get_insert_block().unwrap();
-    let current_function = prehead_bb.get_parent().unwrap();
-    let head_bb = ctx.ctx.append_basic_block(current_function, "rpc.head");
-    let alloc_bb = ctx.ctx.append_basic_block(current_function, "rpc.continue");
-    let tail_bb = ctx.ctx.append_basic_block(current_function, "rpc.tail");
-
-    let ret_ty = ctx.get_llvm_abi_type(generator, fun.0.ret);
-    let need_load = !ret_ty.is_pointer_type();
-    let slot = ctx.builder.build_alloca(ret_ty, "rpc.ret.slot").unwrap();
-    let slotgen = ctx.builder.build_bitcast(slot, ptr_type, "rpc.ret.ptr").unwrap();
-    ctx.builder.build_unconditional_branch(head_bb).unwrap();
-    ctx.builder.position_at_end(head_bb);
-
-    let phi = ctx.builder.build_phi(ptr_type, "rpc.ptr").unwrap();
-    phi.add_incoming(&[(&slotgen, prehead_bb)]);
-    let alloc_size = ctx
-        .build_call_or_invoke(rpc_recv, &[phi.as_basic_value()], "rpc.size.next")
-        .unwrap()
-        .into_int_value();
-    let is_done = ctx
-        .builder
-        .build_int_compare(inkwell::IntPredicate::EQ, int32.const_zero(), alloc_size, "rpc.done")
-        .unwrap();
-
-    ctx.builder.build_conditional_branch(is_done, tail_bb, alloc_bb).unwrap();
-    ctx.builder.position_at_end(alloc_bb);
-
-    let alloc_ptr = ctx.builder.build_array_alloca(ptr_type, alloc_size, "rpc.alloc").unwrap();
-    let alloc_ptr = ctx.builder.build_bitcast(alloc_ptr, ptr_type, "rpc.alloc.ptr").unwrap();
-    phi.add_incoming(&[(&alloc_ptr, alloc_bb)]);
-    ctx.builder.build_unconditional_branch(head_bb).unwrap();
-
-    ctx.builder.position_at_end(tail_bb);
-
-    let result = ctx.builder.build_load(slot, "rpc.result").unwrap();
-    if need_load {
-        call_stackrestore(ctx, stackptr);
-    }
-    Ok(Some(result))
 }
 
-pub fn attributes_writeback(
+pub fn attributes_writeback<'ctx>(
-    ctx: &mut CodeGenContext<'_, '_>,
+    ctx: &mut CodeGenContext<'ctx, '_>,
     generator: &mut dyn CodeGenerator,
     inner_resolver: &InnerResolver,
     host_attributes: &PyObject,
+    return_obj: Option<(Type, ValueEnum<'ctx>)>,
 ) -> Result<(), String> {
     Python::with_gil(|py| -> PyResult<Result<(), String>> {
         let host_attributes: &PyList = host_attributes.downcast(py)?;
@@ -736,6 +977,11 @@ pub fn attributes_writeback(
         let zero = int32.const_zero();
         let mut values = Vec::new();
         let mut scratch_buffer = Vec::new();
+
+        if let Some((ty, obj)) = return_obj {
+            values.push((ty, obj.to_basic_value_enum(ctx, generator, ty).unwrap()));
+        }
+
         for val in (*globals).values() {
             let val = val.as_ref(py);
             let ty = inner_resolver.get_obj_type(
@@ -814,7 +1060,7 @@ pub fn attributes_writeback(
         let args: Vec<_> =
             values.into_iter().map(|(_, val)| (None, ValueEnum::Dynamic(val))).collect();
         if let Err(e) =
-            rpc_codegen_callback_fn(ctx, None, (&fun, PrimDef::Int32.id()), args, generator)
+            rpc_codegen_callback_fn(ctx, None, (&fun, PrimDef::Int32.id()), args, generator, true)
         {
             return Ok(Err(e));
         }
@@ -824,9 +1070,9 @@ pub fn attributes_writeback(
     Ok(())
 }
 
-pub fn rpc_codegen_callback() -> Arc<GenCall> {
+pub fn rpc_codegen_callback(is_async: bool) -> Arc<GenCall> {
-    Arc::new(GenCall::new(Box::new(|ctx, obj, fun, args, generator| {
+    Arc::new(GenCall::new(Box::new(move |ctx, obj, fun, args, generator| {
-        rpc_codegen_callback_fn(ctx, obj, fun, args, generator)
+        rpc_codegen_callback_fn(ctx, obj, fun, args, generator, is_async)
     })))
 }
 
@@ -1040,7 +1286,8 @@ fn polymorphic_print<'ctx>(
                 fmt.push('[');
                 flush(ctx, generator, &mut fmt, &mut args);
 
-                let val = ListValue::from_ptr_val(value.into_pointer_value(), llvm_usize, None);
+                let val =
+                    ListValue::from_pointer_value(value.into_pointer_value(), llvm_usize, None);
                 let len = val.load_size(ctx, None);
                 let last =
                     ctx.builder.build_int_sub(len, llvm_usize.const_int(1, false), "").unwrap();
@@ -1091,56 +1338,50 @@ fn polymorphic_print<'ctx>(
             }
 
             TypeEnum::TObj { obj_id, .. } if *obj_id == PrimDef::NDArray.id() => {
-                let (elem_ty, _) = unpack_ndarray_var_tys(&mut ctx.unifier, ty);
-
                 fmt.push_str("array([");
                 flush(ctx, generator, &mut fmt, &mut args);
 
-                let val = NDArrayValue::from_ptr_val(value.into_pointer_value(), llvm_usize, None);
+                let (dtype, _) = unpack_ndarray_var_tys(&mut ctx.unifier, ty);
-                let len = call_ndarray_calc_size(generator, ctx, &val.dim_sizes(), (None, None));
+                let ndarray = NDArrayType::from_unifier_type(generator, ctx, ty)
-                let last =
+                    .map_value(value.into_pointer_value(), None);
-                    ctx.builder.build_int_sub(len, llvm_usize.const_int(1, false), "").unwrap();
 
-                gen_for_callback_incrementing(
+                let num_0 = llvm_usize.const_zero();
-                    generator,
-                    ctx,
-                    None,
-                    llvm_usize.const_zero(),
-                    (len, false),
-                    |generator, ctx, _, i| {
-                        let elem = unsafe { val.data().get_unchecked(ctx, generator, &i, None) };
 
-                        polymorphic_print(
+                // Print `ndarray` as a flat list delimited by interspersed with ", \0"
-                            ctx,
+                ndarray.foreach(generator, ctx, |generator, ctx, _, hdl| {
-                            generator,
+                    let i = hdl.get_index(ctx);
-                            &[(elem_ty, elem.into())],
+                    let scalar = hdl.get_scalar(ctx);
-                            "",
-                            None,
-                            true,
-                            as_rtio,
-                        )?;
 
-                        gen_if_callback(
+                    // if (i != 0) puts(", ");
-                            generator,
+                    gen_if_callback(
-                            ctx,
+                        generator,
-                            |_, ctx| {
+                        ctx,
-                                Ok(ctx
+                        |_, ctx| {
-                                    .builder
+                            let not_first = ctx
-                                    .build_int_compare(IntPredicate::ULT, i, last, "")
+                                .builder
-                                    .unwrap())
+                                .build_int_compare(IntPredicate::NE, i, num_0, "")
-                            },
+                                .unwrap();
-                            |generator, ctx| {
+                            Ok(not_first)
-                                printf(ctx, generator, ", \0".into(), Vec::default());
+                        },
+                        |generator, ctx| {
+                            printf(ctx, generator, ", \0".into(), Vec::default());
+                            Ok(())
+                        },
+                        |_, _| Ok(()),
+                    )?;
 
-                                Ok(())
+                    // Print element
-                            },
+                    polymorphic_print(
-                            |_, _| Ok(()),
+                        ctx,
-                        )?;
+                        generator,
-
+                        &[(dtype, scalar.into())],
-                        Ok(())
+                        "",
-                    },
+                        None,
-                    llvm_usize.const_int(1, false),
+                        true,
-                )?;
+                        as_rtio,
+                    )?;
+                    Ok(())
+                })?;
 
                 fmt.push_str(")]");
                 flush(ctx, generator, &mut fmt, &mut args);
@@ -1150,7 +1391,7 @@ fn polymorphic_print<'ctx>(
                 fmt.push_str("range(");
                 flush(ctx, generator, &mut fmt, &mut args);
 
-                let val = RangeValue::from_ptr_val(value.into_pointer_value(), None);
+                let val = RangeValue::from_pointer_value(value.into_pointer_value(), None);
 
                 let (start, stop, step) = destructure_range(ctx, val);
 

nac3artiq/src/lib.rs

@@ -1,10 +1,4 @@
-#![deny(
+#![deny(future_incompatible, let_underscore, nonstandard_style, clippy::all)]
-    future_incompatible,
-    let_underscore,
-    nonstandard_style,
-    rust_2024_compatibility,
-    clippy::all
-)]
 #![warn(clippy::pedantic)]
 #![allow(
     unsafe_op_in_unsafe_fn,
@@ -16,64 +10,65 @@
     clippy::wildcard_imports
 )]
 
-use std::collections::{HashMap, HashSet};
+use std::{
-use std::fs;
+    collections::{HashMap, HashSet},
-use std::io::Write;
+    fs,
-use std::process::Command;
+    io::Write,
-use std::rc::Rc;
+    process::Command,
-use std::sync::Arc;
+    rc::Rc,
-
+    sync::Arc,
-use inkwell::{
-    context::Context,
-    memory_buffer::MemoryBuffer,
-    module::{Linkage, Module},
-    passes::PassBuilderOptions,
-    support::is_multithreaded,
-    targets::*,
-    OptimizationLevel,
 };
+
 use itertools::Itertools;
-use nac3core::codegen::{gen_func_impl, CodeGenLLVMOptions, CodeGenTargetMachineOptions};
-use nac3core::toplevel::builtins::get_exn_constructor;
-use nac3core::typecheck::typedef::{into_var_map, TypeEnum, Unifier, VarMap};
-use nac3parser::{
-    ast::{ExprKind, Stmt, StmtKind, StrRef},
-    parser::parse_program,
-};
-use pyo3::create_exception;
-use pyo3::prelude::*;
-use pyo3::{exceptions, types::PyBytes, types::PyDict, types::PySet};
-
 use parking_lot::{Mutex, RwLock};
+use pyo3::{
+    create_exception, exceptions,
+    prelude::*,
+    types::{PyBytes, PyDict, PyNone, PySet},
+};
+use tempfile::{self, TempDir};
 
 use nac3core::{
-    codegen::irrt::load_irrt,
+    codegen::{
-    codegen::{concrete_type::ConcreteTypeStore, CodeGenTask, WithCall, WorkerRegistry},
+        concrete_type::ConcreteTypeStore, gen_func_impl, irrt::load_irrt, CodeGenLLVMOptions,
+        CodeGenTargetMachineOptions, CodeGenTask, CodeGenerator, WithCall, WorkerRegistry,
+    },
+    inkwell::{
+        context::Context,
+        memory_buffer::MemoryBuffer,
+        module::{FlagBehavior, Linkage, Module},
+        passes::PassBuilderOptions,
+        support::is_multithreaded,
+        targets::*,
+        OptimizationLevel,
+    },
+    nac3parser::{
+        ast::{Constant, ExprKind, Located, Stmt, StmtKind, StrRef},
+        parser::parse_program,
+    },
     symbol_resolver::SymbolResolver,
     toplevel::{
+        builtins::get_exn_constructor,
         composer::{BuiltinFuncCreator, BuiltinFuncSpec, ComposerConfig, TopLevelComposer},
         DefinitionId, GenCall, TopLevelDef,
     },
-    typecheck::typedef::{FunSignature, FuncArg},
+    typecheck::{
-    typecheck::{type_inferencer::PrimitiveStore, typedef::Type},
+        type_inferencer::PrimitiveStore,
+        typedef::{into_var_map, FunSignature, FuncArg, Type, TypeEnum, Unifier, VarMap},
+    },
 };
-
 use nac3ld::Linker;
 
-use crate::{
+use codegen::{
-    codegen::{
+    attributes_writeback, gen_core_log, gen_rtio_log, rpc_codegen_callback, ArtiqCodeGenerator,
-        attributes_writeback, gen_core_log, gen_rtio_log, rpc_codegen_callback, ArtiqCodeGenerator,
-    },
-    symbol_resolver::{DeferredEvaluationStore, InnerResolver, PythonHelper, Resolver},
 };
-use tempfile::{self, TempDir};
+use symbol_resolver::{DeferredEvaluationStore, InnerResolver, PythonHelper, Resolver};
+use timeline::TimeFns;
 
 mod codegen;
 mod symbol_resolver;
 mod timeline;
 
-use timeline::TimeFns;
-
 #[derive(PartialEq, Clone, Copy)]
 enum Isa {
     Host,
@@ -147,14 +142,32 @@ impl Nac3 {
         module: &PyObject,
         registered_class_ids: &HashSet<u64>,
     ) -> PyResult<()> {
-        let (module_name, source_file) = Python::with_gil(|py| -> PyResult<(String, String)> {
+        let (module_name, source_file, source) =
-            let module: &PyAny = module.extract(py)?;
+            Python::with_gil(|py| -> PyResult<(String, String, String)> {
-            Ok((module.getattr("__name__")?.extract()?, module.getattr("__file__")?.extract()?))
+                let module: &PyAny = module.extract(py)?;
-        })?;
+                let source_file = module.getattr("__file__");
+                let (source_file, source) = if let Ok(source_file) = source_file {
+                    let source_file = source_file.extract()?;
+                    (
+                        source_file,
+                        fs::read_to_string(source_file).map_err(|e| {
+                            exceptions::PyIOError::new_err(format!(
+                                "failed to read input file: {e}"
+                            ))
+                        })?,
+                    )
+                } else {
+                    // kernels submitted by content have no file
+                    // but still can provide source by StringLoader
+                    let get_src_fn = module
+                        .getattr("__loader__")?
+                        .extract::<PyObject>()?
+                        .getattr(py, "get_source")?;
+                    ("<expcontent>", get_src_fn.call1(py, (PyNone::get(py),))?.extract(py)?)
+                };
+                Ok((module.getattr("__name__")?.extract()?, source_file.to_string(), source))
+            })?;
 
-        let source = fs::read_to_string(&source_file).map_err(|e| {
-            exceptions::PyIOError::new_err(format!("failed to read input file: {e}"))
-        })?;
         let parser_result = parse_program(&source, source_file.into())
             .map_err(|e| exceptions::PySyntaxError::new_err(format!("parse error: {e}")))?;
 
@@ -194,10 +207,8 @@ impl Nac3 {
                     body.retain(|stmt| {
                         if let StmtKind::FunctionDef { ref decorator_list, .. } = stmt.node {
                             decorator_list.iter().any(|decorator| {
-                                if let ExprKind::Name { id, .. } = decorator.node {
+                                if let Some(id) = decorator_id_string(decorator) {
-                                    id.to_string() == "kernel"
+                                    id == "kernel" || id == "portable" || id == "rpc"
-                                        || id.to_string() == "portable"
-                                        || id.to_string() == "rpc"
                                 } else {
                                     false
                                 }
@@ -210,9 +221,8 @@ impl Nac3 {
                 }
                 StmtKind::FunctionDef { ref decorator_list, .. } => {
                     decorator_list.iter().any(|decorator| {
-                        if let ExprKind::Name { id, .. } = decorator.node {
+                        if let Some(id) = decorator_id_string(decorator) {
-                            let id = id.to_string();
+                            id == "extern" || id == "kernel" || id == "portable" || id == "rpc"
-                            id == "extern" || id == "portable" || id == "kernel" || id == "rpc"
                         } else {
                             false
                         }
@@ -448,7 +458,6 @@ impl Nac3 {
                         pyid_to_type: pyid_to_type.clone(),
                         primitive_ids: self.primitive_ids.clone(),
                         global_value_ids: global_value_ids.clone(),
-                        class_names: Mutex::default(),
                         name_to_pyid: name_to_pyid.clone(),
                         module: module.clone(),
                         id_to_pyval: RwLock::default(),
@@ -479,9 +488,25 @@ impl Nac3 {
 
             match &stmt.node {
                 StmtKind::FunctionDef { decorator_list, .. } => {
-                    if decorator_list.iter().any(|decorator| matches!(decorator.node, ExprKind::Name { id, .. } if id == "rpc".into())) {
+                    if decorator_list
-                        store_fun.call1(py, (def_id.0.into_py(py), module.getattr(py, name.to_string().as_str()).unwrap())).unwrap();
+                        .iter()
-                        rpc_ids.push((None, def_id));
+                        .any(|decorator| decorator_id_string(decorator) == Some("rpc".to_string()))
+                    {
+                        store_fun
+                            .call1(
+                                py,
+                                (
+                                    def_id.0.into_py(py),
+                                    module.getattr(py, name.to_string().as_str()).unwrap(),
+                                ),
+                            )
+                            .unwrap();
+                        let is_async = decorator_list.iter().any(|decorator| {
+                            decorator_get_flags(decorator)
+                                .iter()
+                                .any(|constant| *constant == Constant::Str("async".into()))
+                        });
+                        rpc_ids.push((None, def_id, is_async));
                     }
                 }
                 StmtKind::ClassDef { name, body, .. } => {
@@ -489,19 +514,26 @@ impl Nac3 {
                     let class_obj = module.getattr(py, class_name.as_str()).unwrap();
                     for stmt in body {
                         if let StmtKind::FunctionDef { name, decorator_list, .. } = &stmt.node {
-                            if decorator_list.iter().any(|decorator| matches!(decorator.node, ExprKind::Name { id, .. } if id == "rpc".into())) {
+                            if decorator_list.iter().any(|decorator| {
+                                decorator_id_string(decorator) == Some("rpc".to_string())
+                            }) {
+                                let is_async = decorator_list.iter().any(|decorator| {
+                                    decorator_get_flags(decorator)
+                                        .iter()
+                                        .any(|constant| *constant == Constant::Str("async".into()))
+                                });
                                 if name == &"__init__".into() {
                                     return Err(CompileError::new_err(format!(
                                         "compilation failed\n----------\nThe constructor of class {} should not be decorated with rpc decorator (at {})",
                                         class_name, stmt.location
                                     )));
                                 }
-                                rpc_ids.push((Some((class_obj.clone(), *name)), def_id));
+                                rpc_ids.push((Some((class_obj.clone(), *name)), def_id, is_async));
                             }
                         }
                     }
                 }
-                _ => ()
+                _ => (),
             }
 
             let id = *name_to_pyid.get(&name).unwrap();
@@ -540,13 +572,12 @@ impl Nac3 {
             pyid_to_type: pyid_to_type.clone(),
             primitive_ids: self.primitive_ids.clone(),
             global_value_ids: global_value_ids.clone(),
-            class_names: Mutex::default(),
             id_to_pyval: RwLock::default(),
             id_to_primitive: RwLock::default(),
             field_to_val: RwLock::default(),
             name_to_pyid,
             module: module.to_object(py),
-            helper,
+            helper: helper.clone(),
             string_store: self.string_store.clone(),
             exception_ids: self.exception_ids.clone(),
             deferred_eval_store: self.deferred_eval_store.clone(),
@@ -557,6 +588,10 @@ impl Nac3 {
             .register_top_level(synthesized.pop().unwrap(), Some(resolver.clone()), "", false)
             .unwrap();
 
+        // Process IRRT
+        let context = Context::create();
+        let irrt = load_irrt(&context, resolver.as_ref());
+
         let fun_signature =
             FunSignature { args: vec![], ret: self.primitive.none, vars: VarMap::new() };
         let mut store = ConcreteTypeStore::new();
@@ -594,13 +629,12 @@ impl Nac3 {
         let top_level = Arc::new(composer.make_top_level_context());
 
         {
-            let rpc_codegen = rpc_codegen_callback();
             let defs = top_level.definitions.read();
-            for (class_data, id) in &rpc_ids {
+            for (class_data, id, is_async) in &rpc_ids {
                 let mut def = defs[id.0].write();
                 match &mut *def {
                     TopLevelDef::Function { codegen_callback, .. } => {
-                        *codegen_callback = Some(rpc_codegen.clone());
+                        *codegen_callback = Some(rpc_codegen_callback(*is_async));
                     }
                     TopLevelDef::Class { methods, .. } => {
                         let (class_def, method_name) = class_data.as_ref().unwrap();
@@ -611,7 +645,7 @@ impl Nac3 {
                             if let TopLevelDef::Function { codegen_callback, .. } =
                                 &mut *defs[id.0].write()
                             {
-                                *codegen_callback = Some(rpc_codegen.clone());
+                                *codegen_callback = Some(rpc_codegen_callback(*is_async));
                                 store_fun
                                     .call1(
                                         py,
@@ -626,6 +660,11 @@ impl Nac3 {
                             }
                         }
                     }
+                    TopLevelDef::Variable { .. } => {
+                        return Err(CompileError::new_err(String::from(
+                            "Unsupported @rpc annotation on global variable",
+                        )))
+                    }
                 }
             }
         }
@@ -646,33 +685,12 @@ impl Nac3 {
         let task = CodeGenTask {
             subst: Vec::default(),
             symbol_name: "__modinit__".to_string(),
-            body: instance.body,
-            signature,
-            resolver: resolver.clone(),
-            store,
-            unifier_index: instance.unifier_id,
-            calls: instance.calls,
-            id: 0,
-        };
-
-        let mut store = ConcreteTypeStore::new();
-        let mut cache = HashMap::new();
-        let signature = store.from_signature(
-            &mut composer.unifier,
-            &self.primitive,
-            &fun_signature,
-            &mut cache,
-        );
-        let signature = store.add_cty(signature);
-        let attributes_writeback_task = CodeGenTask {
-            subst: Vec::default(),
-            symbol_name: "attributes_writeback".to_string(),
             body: Arc::new(Vec::default()),
             signature,
             resolver,
             store,
             unifier_index: instance.unifier_id,
-            calls: Arc::new(HashMap::default()),
+            calls: instance.calls,
             id: 0,
         };
 
@@ -685,7 +703,7 @@ impl Nac3 {
             let buffer = buffer.as_slice().into();
             membuffer.lock().push(buffer);
         })));
-        let size_t = Context::create()
+        let size_t = context
             .ptr_sized_int_type(&self.get_llvm_target_machine().get_target_data(), None)
             .get_bit_width();
         let num_threads = if is_multithreaded() { 4 } else { 1 };
@@ -696,19 +714,27 @@ impl Nac3 {
             .collect();
 
         let membuffer = membuffers.clone();
+        let mut has_return = false;
         py.allow_threads(|| {
             let (registry, handles) =
                 WorkerRegistry::create_workers(threads, top_level.clone(), &self.llvm_options, &f);
-            registry.add_task(task);
-            registry.wait_tasks_complete(handles);
 
-            let mut generator =
+            let mut generator = ArtiqCodeGenerator::new("main".to_string(), size_t, self.time_fns);
-                ArtiqCodeGenerator::new("attributes_writeback".to_string(), size_t, self.time_fns);
+            let context = Context::create();
-            let context = inkwell::context::Context::create();
+            let module = context.create_module("main");
-            let module = context.create_module("attributes_writeback");
             let target_machine = self.llvm_options.create_target_machine().unwrap();
             module.set_data_layout(&target_machine.get_target_data().get_data_layout());
             module.set_triple(&target_machine.get_triple());
+            module.add_basic_value_flag(
+                "Debug Info Version",
+                FlagBehavior::Warning,
+                context.i32_type().const_int(3, false),
+            );
+            module.add_basic_value_flag(
+                "Dwarf Version",
+                FlagBehavior::Warning,
+                context.i32_type().const_int(4, false),
+            );
             let builder = context.create_builder();
             let (_, module, _) = gen_func_impl(
                 &context,
@@ -716,9 +742,27 @@ impl Nac3 {
                 &registry,
                 builder,
                 module,
-                attributes_writeback_task,
+                task,
                 |generator, ctx| {
-                    attributes_writeback(ctx, generator, inner_resolver.as_ref(), &host_attributes)
+                    assert_eq!(instance.body.len(), 1, "toplevel module should have 1 statement");
+                    let StmtKind::Expr { value: ref expr, .. } = instance.body[0].node else {
+                        unreachable!("toplevel statement must be an expression")
+                    };
+                    let ExprKind::Call { .. } = expr.node else {
+                        unreachable!("toplevel expression must be a function call")
+                    };
+
+                    let return_obj =
+                        generator.gen_expr(ctx, expr)?.map(|value| (expr.custom.unwrap(), value));
+                    has_return = return_obj.is_some();
+                    registry.wait_tasks_complete(handles);
+                    attributes_writeback(
+                        ctx,
+                        generator,
+                        inner_resolver.as_ref(),
+                        &host_attributes,
+                        return_obj,
+                    )
                 },
             )
             .unwrap();
@@ -727,37 +771,24 @@ impl Nac3 {
             membuffer.lock().push(buffer);
         });
 
-        let context = inkwell::context::Context::create();
+        embedding_map.setattr("expects_return", has_return).unwrap();
+
+        // Link all modules into `main`.
         let buffers = membuffers.lock();
         let main = context
-            .create_module_from_ir(MemoryBuffer::create_from_memory_range(&buffers[0], "main"))
+            .create_module_from_ir(MemoryBuffer::create_from_memory_range(
+                buffers.last().unwrap(),
+                "main",
+            ))
             .unwrap();
-        for buffer in buffers.iter().skip(1) {
+        for buffer in buffers.iter().rev().skip(1) {
             let other = context
                 .create_module_from_ir(MemoryBuffer::create_from_memory_range(buffer, "main"))
                 .unwrap();
 
             main.link_in_module(other).map_err(|err| CompileError::new_err(err.to_string()))?;
         }
-        let builder = context.create_builder();
+        main.link_in_module(irrt).map_err(|err| CompileError::new_err(err.to_string()))?;
-        let modinit_return = main
-            .get_function("__modinit__")
-            .unwrap()
-            .get_last_basic_block()
-            .unwrap()
-            .get_terminator()
-            .unwrap();
-        builder.position_before(&modinit_return);
-        builder
-            .build_call(
-                main.get_function("attributes_writeback").unwrap(),
-                &[],
-                "attributes_writeback",
-            )
-            .unwrap();
-
-        main.link_in_module(load_irrt(&context))
-            .map_err(|err| CompileError::new_err(err.to_string()))?;
 
         let mut function_iter = main.get_first_function();
         while let Some(func) = function_iter {
@@ -791,6 +822,20 @@ impl Nac3 {
             panic!("Failed to run optimization for module `main`: {}", err.to_string());
         }
 
+        Python::with_gil(|py| {
+            let string_store = self.string_store.read();
+            let mut string_store_vec = string_store.iter().collect::<Vec<_>>();
+            string_store_vec.sort_by(|(_s1, key1), (_s2, key2)| key1.cmp(key2));
+            for (s, key) in string_store_vec {
+                let embed_key: i32 = helper.store_str.call1(py, (s,)).unwrap().extract(py).unwrap();
+                assert_eq!(
+                    embed_key, *key,
+                    "string {s} is out of sync between embedding map (key={embed_key}) and \
+                    the internal string store (key={key})"
+                );
+            }
+        });
+
         link_fn(&main)
     }
 
@@ -843,6 +888,41 @@ impl Nac3 {
     }
 }
 
+/// Retrieves the Name.id from a decorator, supports decorators with arguments.
+fn decorator_id_string(decorator: &Located<ExprKind>) -> Option<String> {
+    if let ExprKind::Name { id, .. } = decorator.node {
+        // Bare decorator
+        return Some(id.to_string());
+    } else if let ExprKind::Call { func, .. } = &decorator.node {
+        // Decorators that are calls (e.g. "@rpc()") have Call for the node,
+        // need to extract the id from within.
+        if let ExprKind::Name { id, .. } = func.node {
+            return Some(id.to_string());
+        }
+    }
+    None
+}
+
+/// Retrieves flags from a decorator, if any.
+fn decorator_get_flags(decorator: &Located<ExprKind>) -> Vec<Constant> {
+    let mut flags = vec![];
+    if let ExprKind::Call { keywords, .. } = &decorator.node {
+        for keyword in keywords {
+            if keyword.node.arg != Some("flags".into()) {
+                continue;
+            }
+            if let ExprKind::Set { elts } = &keyword.node.value.node {
+                for elt in elts {
+                    if let ExprKind::Constant { value, .. } = &elt.node {
+                        flags.push(value.clone());
+                    }
+                }
+            }
+        }
+    }
+    flags
+}
+
 fn link_with_lld(elf_filename: String, obj_filename: String) -> PyResult<()> {
     let linker_args = vec![
         "-shared".to_string(),
@@ -1005,6 +1085,48 @@ impl Nac3 {
         let working_directory = tempfile::Builder::new().prefix("nac3-").tempdir().unwrap();
         fs::write(working_directory.path().join("kernel.ld"), include_bytes!("kernel.ld")).unwrap();
 
+        let mut string_store: HashMap<String, i32> = HashMap::default();
+
+        // Keep this list of exceptions in sync with `EXCEPTION_ID_LOOKUP` in `artiq::firmware::ksupport::eh_artiq`
+        // The exceptions declared here must be defined in `artiq.coredevice.exceptions`
+        // Verify synchronization by running the test cases in `artiq.test.coredevice.test_exceptions`
+        let runtime_exception_names = [
+            "RTIOUnderflow",
+            "RTIOOverflow",
+            "RTIODestinationUnreachable",
+            "DMAError",
+            "I2CError",
+            "CacheError",
+            "SPIError",
+            "SubkernelError",
+            "0:AssertionError",
+            "0:AttributeError",
+            "0:IndexError",
+            "0:IOError",
+            "0:KeyError",
+            "0:NotImplementedError",
+            "0:OverflowError",
+            "0:RuntimeError",
+            "0:TimeoutError",
+            "0:TypeError",
+            "0:ValueError",
+            "0:ZeroDivisionError",
+            "0:LinAlgError",
+            "UnwrapNoneError",
+        ];
+
+        // Preallocate runtime exception names
+        for (i, name) in runtime_exception_names.iter().enumerate() {
+            let exn_name = if name.find(':').is_none() {
+                format!("0:artiq.coredevice.exceptions.{name}")
+            } else {
+                (*name).to_string()
+            };
+
+            let id = i32::try_from(i).unwrap();
+            string_store.insert(exn_name, id);
+        }
+
         Ok(Nac3 {
             isa,
             time_fns,
@@ -1014,7 +1136,7 @@ impl Nac3 {
             top_levels: Vec::default(),
             pyid_to_def: Arc::default(),
             working_directory,
-            string_store: Arc::default(),
+            string_store: Arc::new(string_store.into()),
             exception_ids: Arc::default(),
             deferred_eval_store: DeferredEvaluationStore::new(),
             llvm_options: CodeGenLLVMOptions {
@@ -1024,7 +1146,12 @@ impl Nac3 {
         })
     }
 
-    fn analyze(&mut self, functions: &PySet, classes: &PySet) -> PyResult<()> {
+    fn analyze(
+        &mut self,
+        functions: &PySet,
+        classes: &PySet,
+        content_modules: &PySet,
+    ) -> PyResult<()> {
         let (modules, class_ids) =
             Python::with_gil(|py| -> PyResult<(HashMap<u64, PyObject>, HashSet<u64>)> {
                 let mut modules: HashMap<u64, PyObject> = HashMap::new();
@@ -1034,14 +1161,22 @@ impl Nac3 {
                 let getmodule_fn = PyModule::import(py, "inspect")?.getattr("getmodule")?;
 
                 for function in functions {
-                    let module = getmodule_fn.call1((function,))?.extract()?;
+                    let module: PyObject = getmodule_fn.call1((function,))?.extract()?;
-                    modules.insert(id_fn.call1((&module,))?.extract()?, module);
+                    if !module.is_none(py) {
+                        modules.insert(id_fn.call1((&module,))?.extract()?, module);
+                    }
                 }
                 for class in classes {
-                    let module = getmodule_fn.call1((class,))?.extract()?;
+                    let module: PyObject = getmodule_fn.call1((class,))?.extract()?;
-                    modules.insert(id_fn.call1((&module,))?.extract()?, module);
+                    if !module.is_none(py) {
+                        modules.insert(id_fn.call1((&module,))?.extract()?, module);
+                    }
                     class_ids.insert(id_fn.call1((class,))?.extract()?);
                 }
+                for module in content_modules {
+                    let module: PyObject = module.extract()?;
+                    modules.insert(id_fn.call1((&module,))?.extract()?, module);
+                }
                 Ok((modules, class_ids))
             })?;
 

nac3artiq/src/symbol_resolver.rs

@@ -1,16 +1,32 @@
-use crate::PrimitivePythonId;
+use std::{
-use inkwell::{
+    collections::{HashMap, HashSet},
-    module::Linkage,
+    sync::{
-    types::{BasicType, BasicTypeEnum},
+        atomic::{AtomicBool, Ordering::Relaxed},
-    values::BasicValueEnum,
+        Arc,
-    AddressSpace,
+    },
 };
+
 use itertools::Itertools;
+use parking_lot::RwLock;
+use pyo3::{
+    types::{PyDict, PyTuple},
+    PyAny, PyErr, PyObject, PyResult, Python,
+};
+
+use super::PrimitivePythonId;
 use nac3core::{
     codegen::{
-        classes::{NDArrayType, ProxyType},
+        types::{ndarray::NDArrayType, ProxyType},
+        values::ndarray::make_contiguous_strides,
         CodeGenContext, CodeGenerator,
     },
+    inkwell::{
+        module::Linkage,
+        types::{BasicType, BasicTypeEnum},
+        values::BasicValueEnum,
+        AddressSpace,
+    },
+    nac3parser::ast::{self, StrRef},
     symbol_resolver::{StaticValue, SymbolResolver, SymbolValue, ValueEnum},
     toplevel::{
         helper::PrimDef,
@@ -22,19 +38,6 @@ use nac3core::{
         typedef::{into_var_map, iter_type_vars, Type, TypeEnum, TypeVar, Unifier, VarMap},
     },
 };
-use nac3parser::ast::{self, StrRef};
-use parking_lot::{Mutex, RwLock};
-use pyo3::{
-    types::{PyDict, PyTuple},
-    PyAny, PyObject, PyResult, Python,
-};
-use std::{
-    collections::{HashMap, HashSet},
-    sync::{
-        atomic::{AtomicBool, Ordering::Relaxed},
-        Arc,
-    },
-};
 
 pub enum PrimitiveValue {
     I32(i32),
@@ -79,7 +82,6 @@ pub struct InnerResolver {
     pub id_to_primitive: RwLock<HashMap<u64, PrimitiveValue>>,
     pub field_to_val: RwLock<HashMap<ResolverField, Option<PyFieldHandle>>>,
     pub global_value_ids: Arc<RwLock<HashMap<u64, PyObject>>>,
-    pub class_names: Mutex<HashMap<StrRef, Type>>,
     pub pyid_to_def: Arc<RwLock<HashMap<u64, DefinitionId>>>,
     pub pyid_to_type: Arc<RwLock<HashMap<u64, Type>>>,
     pub primitive_ids: PrimitivePythonId,
@@ -1083,18 +1085,19 @@ impl InnerResolver {
             } else {
                 unreachable!("must be ndarray")
             };
-            let (ndarray_dtype, ndarray_ndims) =
+            let (ndarray_dtype, _) = unpack_ndarray_var_tys(&mut ctx.unifier, ndarray_ty);
-                unpack_ndarray_var_tys(&mut ctx.unifier, ndarray_ty);
 
+            let llvm_i8 = ctx.ctx.i8_type();
+            let llvm_pi8 = llvm_i8.ptr_type(AddressSpace::default());
             let llvm_usize = generator.get_size_type(ctx.ctx);
-            let ndarray_dtype_llvm_ty = ctx.get_llvm_type(generator, ndarray_dtype);
+            let llvm_ndarray = NDArrayType::from_unifier_type(generator, ctx, ndarray_ty);
-            let ndarray_llvm_ty = NDArrayType::new(generator, ctx.ctx, ndarray_dtype_llvm_ty);
+            let dtype = llvm_ndarray.element_type();
 
             {
                 if self.global_value_ids.read().contains_key(&id) {
                     let global = ctx.module.get_global(&id_str).unwrap_or_else(|| {
                         ctx.module.add_global(
-                            ndarray_llvm_ty.as_underlying_type(),
+                            llvm_ndarray.as_base_type().get_element_type().into_struct_type(),
                             Some(AddressSpace::default()),
                             &id_str,
                         )
@@ -1104,40 +1107,41 @@ impl InnerResolver {
                 self.global_value_ids.write().insert(id, obj.into());
             }
 
-            let TypeEnum::TLiteral { values, .. } = &*ctx.unifier.get_ty_immutable(ndarray_ndims)
+            let ndims = llvm_ndarray.ndims().unwrap();
-            else {
-                unreachable!("Expected Literal for ndarray_ndims")
-            };
-
-            let ndarray_ndims = if values.len() == 1 {
-                values[0].clone()
-            } else {
-                todo!("Unpacking literal of more than one element unimplemented")
-            };
-            let Ok(ndarray_ndims) = u64::try_from(ndarray_ndims) else {
-                unreachable!("Expected u64 value for ndarray_ndims")
-            };
 
             // Obtain the shape of the ndarray
             let shape_tuple: &PyTuple = obj.getattr("shape")?.downcast()?;
-            assert_eq!(shape_tuple.len(), ndarray_ndims as usize);
+            assert_eq!(shape_tuple.len(), ndims as usize);
-            let shape_values: Result<Option<Vec<_>>, _> = shape_tuple
+
+            // The Rust type inferencer cannot figure this out
+            let shape_values = shape_tuple
                 .iter()
                 .enumerate()
                 .map(|(i, elem)| {
-                    self.get_obj_value(py, elem, ctx, generator, ctx.primitives.usize()).map_err(
+                    let value = self
-                        |e| super::CompileError::new_err(format!("Error getting element {i}: {e}")),
+                        .get_obj_value(py, elem, ctx, generator, ctx.primitives.usize())
-                    )
+                        .map_err(|e| {
+                            super::CompileError::new_err(format!("Error getting element {i}: {e}"))
+                        })?
+                        .unwrap();
+                    let value = value.into_int_value();
+                    Ok(value)
                 })
-                .collect();
+                .collect::<Result<Vec<_>, PyErr>>()?;
-            let shape_values = shape_values?.unwrap();
+
-            let shape_values = llvm_usize.const_array(
+            // Also use this opportunity to get the constant values of `shape_values` for calculating strides.
-                &shape_values.into_iter().map(BasicValueEnum::into_int_value).collect_vec(),
+            let shape_u64s = shape_values
-            );
+                .iter()
+                .map(|dim| {
+                    assert!(dim.is_const());
+                    dim.get_zero_extended_constant().unwrap()
+                })
+                .collect_vec();
+            let shape_values = llvm_usize.const_array(&shape_values);
 
             // create a global for ndarray.shape and initialize it using the shape
             let shape_global = ctx.module.add_global(
-                llvm_usize.array_type(ndarray_ndims as u32),
+                llvm_usize.array_type(ndims as u32),
                 Some(AddressSpace::default()),
                 &(id_str.clone() + ".shape"),
             );
@@ -1145,17 +1149,25 @@ impl InnerResolver {
 
             // Obtain the (flattened) elements of the ndarray
             let sz: usize = obj.getattr("size")?.extract()?;
-            let data: Result<Option<Vec<_>>, _> = (0..sz)
+            let data: Vec<_> = (0..sz)
                 .map(|i| {
                     obj.getattr("flat")?.get_item(i).and_then(|elem| {
-                        self.get_obj_value(py, elem, ctx, generator, ndarray_dtype).map_err(|e| {
+                        let value = self
-                            super::CompileError::new_err(format!("Error getting element {i}: {e}"))
+                            .get_obj_value(py, elem, ctx, generator, ndarray_dtype)
-                        })
+                            .map_err(|e| {
+                                super::CompileError::new_err(format!(
+                                    "Error getting element {i}: {e}"
+                                ))
+                            })?
+                            .unwrap();
+
+                        assert_eq!(value.get_type(), dtype);
+                        Ok(value)
                     })
                 })
-                .collect();
+                .try_collect()?;
-            let data = data?.unwrap().into_iter();
+            let data = data.into_iter();
-            let data = match ndarray_dtype_llvm_ty {
+            let data = match dtype {
                 BasicTypeEnum::ArrayType(ty) => {
                     ty.const_array(&data.map(BasicValueEnum::into_array_value).collect_vec())
                 }
@@ -1180,34 +1192,68 @@ impl InnerResolver {
             };
 
             // create a global for ndarray.data and initialize it using the elements
+            //
+            // NOTE: NDArray's `data` is `u8*`. Here, `data_global` is an array of `dtype`.
+            // We will have to cast it to an `u8*` later.
             let data_global = ctx.module.add_global(
-                ndarray_dtype_llvm_ty.array_type(sz as u32),
+                dtype.array_type(sz as u32),
                 Some(AddressSpace::default()),
                 &(id_str.clone() + ".data"),
             );
             data_global.set_initializer(&data);
 
-            // create a global for the ndarray object and initialize it
+            // Get the constant itemsize.
-            let value = ndarray_llvm_ty.as_underlying_type().const_named_struct(&[
+            let itemsize = dtype.size_of().unwrap();
-                llvm_usize.const_int(ndarray_ndims, false).into(),
+            let itemsize = itemsize.get_zero_extended_constant().unwrap();
-                shape_global
-                    .as_pointer_value()
-                    .const_cast(llvm_usize.ptr_type(AddressSpace::default()))
-                    .into(),
-                data_global
-                    .as_pointer_value()
-                    .const_cast(ndarray_dtype_llvm_ty.ptr_type(AddressSpace::default()))
-                    .into(),
-            ]);
 
-            let ndarray = ctx.module.add_global(
+            // Create the strides needed for ndarray.strides
-                ndarray_llvm_ty.as_underlying_type(),
+            let strides = make_contiguous_strides(itemsize, ndims, &shape_u64s);
+            let strides =
+                strides.into_iter().map(|stride| llvm_usize.const_int(stride, false)).collect_vec();
+            let strides = llvm_usize.const_array(&strides);
+
+            // create a global for ndarray.strides and initialize it
+            let strides_global = ctx.module.add_global(
+                llvm_i8.array_type(ndims as u32),
+                Some(AddressSpace::default()),
+                &format!("${id_str}.strides"),
+            );
+            strides_global.set_initializer(&strides);
+
+            // create a global for the ndarray object and initialize it
+
+            // NOTE: data_global is an array of dtype, we want a `u8*`.
+            let ndarray_data = data_global.as_pointer_value();
+            let ndarray_data = ctx.builder.build_pointer_cast(ndarray_data, llvm_pi8, "").unwrap();
+
+            let ndarray_itemsize = llvm_usize.const_int(itemsize, false);
+
+            let ndarray_ndims = llvm_usize.const_int(ndims, false);
+
+            let ndarray_shape = shape_global.as_pointer_value();
+
+            let ndarray_strides = strides_global.as_pointer_value();
+
+            let ndarray = llvm_ndarray
+                .as_base_type()
+                .get_element_type()
+                .into_struct_type()
+                .const_named_struct(&[
+                    ndarray_itemsize.into(),
+                    ndarray_ndims.into(),
+                    ndarray_shape.into(),
+                    ndarray_strides.into(),
+                    ndarray_data.into(),
+                ]);
+
+            let ndarray_global = ctx.module.add_global(
+                llvm_ndarray.as_base_type().get_element_type().into_struct_type(),
                 Some(AddressSpace::default()),
                 &id_str,
             );
-            ndarray.set_initializer(&value);
+            ndarray_global.set_initializer(&ndarray);
 
-            Ok(Some(ndarray.as_pointer_value().into()))
+            Ok(Some(ndarray_global.as_pointer_value().into()))
         } else if ty_id == self.primitive_ids.tuple {
             let expected_ty_enum = ctx.unifier.get_ty_immutable(expected_ty);
             let TypeEnum::TTuple { ty, is_vararg_ctx: false } = expected_ty_enum.as_ref() else {
@@ -1468,6 +1514,7 @@ impl SymbolResolver for Resolver {
         &self,
         id: StrRef,
         _: &mut CodeGenContext<'ctx, '_>,
+        _: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>> {
         let sym_value = {
             let id_to_val = self.0.id_to_pyval.read();
@@ -1529,10 +1576,7 @@ impl SymbolResolver for Resolver {
         if let Some(id) = string_store.get(s) {
             *id
         } else {
-            let id = Python::with_gil(|py| -> PyResult<i32> {
+            let id = i32::try_from(string_store.len()).unwrap();
-                self.0.helper.store_str.call1(py, (s,))?.extract(py)
-            })
-            .unwrap();
             string_store.insert(s.into(), id);
             id
         }

nac3artiq/src/timeline.rs

@@ -1,9 +1,12 @@
-use inkwell::{
-    values::{BasicValueEnum, CallSiteValue},
-    AddressSpace, AtomicOrdering,
-};
 use itertools::Either;
-use nac3core::codegen::CodeGenContext;
+
+use nac3core::{
+    codegen::CodeGenContext,
+    inkwell::{
+        values::{BasicValueEnum, CallSiteValue},
+        AddressSpace, AtomicOrdering,
+    },
+};
 
 /// Functions for manipulating the timeline.
 pub trait TimeFns {
@@ -31,7 +34,7 @@ impl TimeFns for NowPinningTimeFns64 {
             .unwrap_or_else(|| ctx.module.add_global(i64_type, None, "now"));
         let now_hiptr = ctx
             .builder
-            .build_bitcast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
+            .build_bit_cast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
             .map(BasicValueEnum::into_pointer_value)
             .unwrap();
 
@@ -80,7 +83,7 @@ impl TimeFns for NowPinningTimeFns64 {
             .unwrap_or_else(|| ctx.module.add_global(i64_type, None, "now"));
         let now_hiptr = ctx
             .builder
-            .build_bitcast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
+            .build_bit_cast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
             .map(BasicValueEnum::into_pointer_value)
             .unwrap();
 
@@ -109,7 +112,7 @@ impl TimeFns for NowPinningTimeFns64 {
             .unwrap_or_else(|| ctx.module.add_global(i64_type, None, "now"));
         let now_hiptr = ctx
             .builder
-            .build_bitcast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
+            .build_bit_cast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
             .map(BasicValueEnum::into_pointer_value)
             .unwrap();
 
@@ -207,7 +210,7 @@ impl TimeFns for NowPinningTimeFns {
             .unwrap_or_else(|| ctx.module.add_global(i64_type, None, "now"));
         let now_hiptr = ctx
             .builder
-            .build_bitcast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
+            .build_bit_cast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
             .map(BasicValueEnum::into_pointer_value)
             .unwrap();
 
@@ -258,7 +261,7 @@ impl TimeFns for NowPinningTimeFns {
         let time_lo = ctx.builder.build_int_truncate(time, i32_type, "time.lo").unwrap();
         let now_hiptr = ctx
             .builder
-            .build_bitcast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
+            .build_bit_cast(now, i32_type.ptr_type(AddressSpace::default()), "now.hi.addr")
             .map(BasicValueEnum::into_pointer_value)
             .unwrap();
 

nac3ast/Cargo.toml

@@ -10,7 +10,6 @@ constant-optimization = ["fold"]
 fold = []
 
 [dependencies]
-lazy_static = "1.5"
 parking_lot = "0.12"
 string-interner = "0.17"
 fxhash = "0.2"

nac3ast/src/ast_gen.rs

@@ -5,14 +5,12 @@ pub use crate::location::Location;
 
 use fxhash::FxBuildHasher;
 use parking_lot::{Mutex, MutexGuard};
-use std::{cell::RefCell, collections::HashMap, fmt};
+use std::{cell::RefCell, collections::HashMap, fmt, sync::LazyLock};
 use string_interner::{symbol::SymbolU32, DefaultBackend, StringInterner};
 
 pub type Interner = StringInterner<DefaultBackend, FxBuildHasher>;
-lazy_static! {
+static INTERNER: LazyLock<Mutex<Interner>> =
-    static ref INTERNER: Mutex<Interner> =
+    LazyLock::new(|| Mutex::new(StringInterner::with_hasher(FxBuildHasher::default())));
-        Mutex::new(StringInterner::with_hasher(FxBuildHasher::default()));
-}
 
 thread_local! {
     static LOCAL_INTERNER: RefCell<HashMap<String, StrRef>> = RefCell::default();

nac3ast/src/lib.rs

@@ -1,10 +1,4 @@
-#![deny(
+#![deny(future_incompatible, let_underscore, nonstandard_style, clippy::all)]
-    future_incompatible,
-    let_underscore,
-    nonstandard_style,
-    rust_2024_compatibility,
-    clippy::all
-)]
 #![warn(clippy::pedantic)]
 #![allow(
     clippy::missing_errors_doc,
@@ -14,9 +8,6 @@
     clippy::wildcard_imports
 )]
 
-#[macro_use]
-extern crate lazy_static;
-
 mod ast_gen;
 mod constant;
 #[cfg(feature = "fold")]

nac3core/Cargo.toml

@@ -5,22 +5,25 @@ authors = ["M-Labs"]
 edition = "2021"
 
 [features]
+default = ["derive"]
+derive = ["dep:nac3core_derive"]
 no-escape-analysis = []
 
 [dependencies]
 itertools = "0.13"
 crossbeam = "0.8"
-indexmap = "2.2"
+indexmap = "2.6"
 parking_lot = "0.12"
-rayon = "1.8"
+rayon = "1.10"
+nac3core_derive = { path = "nac3core_derive", optional = true }
 nac3parser = { path = "../nac3parser" }
 strum = "0.26"
 strum_macros = "0.26"
 
 [dependencies.inkwell]
-version = "0.4"
+version = "0.5"
 default-features = false
-features = ["llvm14-0", "target-x86", "target-arm", "target-riscv", "no-libffi-linking"]
+features = ["llvm14-0-prefer-dynamic", "target-x86", "target-arm", "target-riscv", "no-libffi-linking"]
 
 [dev-dependencies]
 test-case = "1.2.0"

nac3core/build.rs

@@ -1,4 +1,3 @@
-use regex::Regex;
 use std::{
     env,
     fs::File,
@@ -7,44 +6,58 @@ use std::{
     process::{Command, Stdio},
 };
 
+use regex::Regex;
+
 fn main() {
-    const FILE: &str = "src/codegen/irrt/irrt.cpp";
+    let out_dir = env::var("OUT_DIR").unwrap();
+    let out_dir = Path::new(&out_dir);
+    let irrt_dir = Path::new("irrt");
+
+    let irrt_cpp_path = irrt_dir.join("irrt.cpp");
 
     /*
      * HACK: Sadly, clang doesn't let us emit generic LLVM bitcode.
      * Compiling for WASM32 and filtering the output with regex is the closest we can get.
      */
-    let flags: &[&str] = &[
+    let mut flags: Vec<&str> = vec![
         "--target=wasm32",
-        FILE,
         "-x",
         "c++",
+        "-std=c++20",
         "-fno-discard-value-names",
         "-fno-exceptions",
         "-fno-rtti",
-        match env::var("PROFILE").as_deref() {
-            Ok("debug") => "-O0",
-            Ok("release") => "-O3",
-            flavor => panic!("Unknown or missing build flavor {flavor:?}"),
-        },
         "-emit-llvm",
         "-S",
         "-Wall",
         "-Wextra",
         "-o",
         "-",
+        "-I",
+        irrt_dir.to_str().unwrap(),
+        irrt_cpp_path.to_str().unwrap(),
     ];
 
-    println!("cargo:rerun-if-changed={FILE}");
+    match env::var("PROFILE").as_deref() {
-    let out_dir = env::var("OUT_DIR").unwrap();
+        Ok("debug") => {
-    let out_path = Path::new(&out_dir);
+            flags.push("-O0");
+            flags.push("-DIRRT_DEBUG_ASSERT");
+        }
+        Ok("release") => {
+            flags.push("-O3");
+        }
+        flavor => panic!("Unknown or missing build flavor {flavor:?}"),
+    }
 
+    // Tell Cargo to rerun if any file under `irrt_dir` (recursive) changes
+    println!("cargo:rerun-if-changed={}", irrt_dir.to_str().unwrap());
+
+    // Compile IRRT and capture the LLVM IR output
     let output = Command::new("clang-irrt")
         .args(flags)
         .output()
-        .map(|o| {
+        .inspect(|o| {
             assert!(o.status.success(), "{}", std::str::from_utf8(&o.stderr).unwrap());
-            o
         })
         .unwrap();
 
@@ -52,7 +65,17 @@ fn main() {
     let output = std::str::from_utf8(&output.stdout).unwrap().replace("\r\n", "\n");
     let mut filtered_output = String::with_capacity(output.len());
 
-    let regex_filter = Regex::new(r"(?ms:^define.*?\}$)|(?m:^declare.*?$)").unwrap();
+    // Filter out irrelevant IR
+    //
+    // Regex:
+    // - `(?ms:^define.*?\}$)` captures LLVM `define` blocks
+    // - `(?m:^declare.*?$)` captures LLVM `declare` lines
+    // - `(?m:^%.+?=\s*type\s*\{.+?\}$)` captures LLVM `type` declarations
+    // - `(?m:^@.+?=.+$)` captures global constants
+    let regex_filter = Regex::new(
+        r"(?ms:^define.*?\}$)|(?m:^declare.*?$)|(?m:^%.+?=\s*type\s*\{.+?\}$)|(?m:^@.+?=.+$)",
+    )
+    .unwrap();
     for f in regex_filter.captures_iter(&output) {
         assert_eq!(f.len(), 1);
         filtered_output.push_str(&f[0]);
@@ -63,18 +86,22 @@ fn main() {
         .unwrap()
         .replace_all(&filtered_output, "");
 
-    println!("cargo:rerun-if-env-changed=DEBUG_DUMP_IRRT");
+    // For debugging
-    if env::var("DEBUG_DUMP_IRRT").is_ok() {
+    // Doing `DEBUG_DUMP_IRRT=1 cargo build -p nac3core` dumps the LLVM IR generated
-        let mut file = File::create(out_path.join("irrt.ll")).unwrap();
+    const DEBUG_DUMP_IRRT: &str = "DEBUG_DUMP_IRRT";
+    println!("cargo:rerun-if-env-changed={DEBUG_DUMP_IRRT}");
+    if env::var(DEBUG_DUMP_IRRT).is_ok() {
+        let mut file = File::create(out_dir.join("irrt.ll")).unwrap();
         file.write_all(output.as_bytes()).unwrap();
-        let mut file = File::create(out_path.join("irrt-filtered.ll")).unwrap();
+
+        let mut file = File::create(out_dir.join("irrt-filtered.ll")).unwrap();
         file.write_all(filtered_output.as_bytes()).unwrap();
     }
 
     let mut llvm_as = Command::new("llvm-as-irrt")
         .stdin(Stdio::piped())
         .arg("-o")
-        .arg(out_path.join("irrt.bc"))
+        .arg(out_dir.join("irrt.bc"))
         .spawn()
         .unwrap();
     llvm_as.stdin.as_mut().unwrap().write_all(filtered_output.as_bytes()).unwrap();

nac3core/irrt/irrt.cpp

@@ -0,0 +1,10 @@
+#include "irrt/exception.hpp"
+#include "irrt/list.hpp"
+#include "irrt/math.hpp"
+#include "irrt/ndarray.hpp"
+#include "irrt/range.hpp"
+#include "irrt/slice.hpp"
+#include "irrt/ndarray/basic.hpp"
+#include "irrt/ndarray/def.hpp"
+#include "irrt/ndarray/iter.hpp"
+#include "irrt/ndarray/indexing.hpp"

nac3core/irrt/irrt/cslice.hpp

@@ -0,0 +1,9 @@
+#pragma once
+
+#include "irrt/int_types.hpp"
+
+template<typename SizeT>
+struct CSlice {
+    void* base;
+    SizeT len;
+};

nac3core/irrt/irrt/debug.hpp

@@ -0,0 +1,25 @@
+#pragma once
+
+// Set in nac3core/build.rs
+#ifdef IRRT_DEBUG_ASSERT
+#define IRRT_DEBUG_ASSERT_BOOL true
+#else
+#define IRRT_DEBUG_ASSERT_BOOL false
+#endif
+
+#define raise_debug_assert(SizeT, msg, param1, param2, param3) \
+    raise_exception(SizeT, EXN_ASSERTION_ERROR, "IRRT debug assert failed: " msg, param1, param2, param3)
+
+#define debug_assert_eq(SizeT, lhs, rhs)                                           \
+    if constexpr (IRRT_DEBUG_ASSERT_BOOL) {                                        \
+        if ((lhs) != (rhs)) {                                                      \
+            raise_debug_assert(SizeT, "LHS = {0}. RHS = {1}", lhs, rhs, NO_PARAM); \
+        }                                                                          \
+    }
+
+#define debug_assert(SizeT, expr)                                                  \
+    if constexpr (IRRT_DEBUG_ASSERT_BOOL) {                                        \
+        if (!(expr)) {                                                             \
+            raise_debug_assert(SizeT, "Got false.", NO_PARAM, NO_PARAM, NO_PARAM); \
+        }                                                                          \
+    }

nac3core/irrt/irrt/exception.hpp

@@ -0,0 +1,85 @@
+#pragma once
+
+#include "irrt/cslice.hpp"
+#include "irrt/int_types.hpp"
+
+/**
+ * @brief The int type of ARTIQ exception IDs.
+ */
+using ExceptionId = int32_t;
+
+/*
+ * Set of exceptions C++ IRRT can use.
+ * Must be synchronized with `setup_irrt_exceptions` in `nac3core/src/codegen/irrt/mod.rs`.
+ */
+extern "C" {
+ExceptionId EXN_INDEX_ERROR;
+ExceptionId EXN_VALUE_ERROR;
+ExceptionId EXN_ASSERTION_ERROR;
+ExceptionId EXN_TYPE_ERROR;
+}
+
+/**
+ * @brief Extern function to `__nac3_raise`
+ *
+ * The parameter `err` could be `Exception<int32_t>` or `Exception<int64_t>`. The caller
+ * must make sure to pass `Exception`s with the correct `SizeT` depending on the `size_t` of the runtime.
+ */
+extern "C" void __nac3_raise(void* err);
+
+namespace {
+/**
+ * @brief NAC3's Exception struct
+ */
+template<typename SizeT>
+struct Exception {
+    ExceptionId id;
+    CSlice<SizeT> filename;
+    int32_t line;
+    int32_t column;
+    CSlice<SizeT> function;
+    CSlice<SizeT> msg;
+    int64_t params[3];
+};
+
+constexpr int64_t NO_PARAM = 0;
+
+template<typename SizeT>
+void _raise_exception_helper(ExceptionId id,
+                             const char* filename,
+                             int32_t line,
+                             const char* function,
+                             const char* msg,
+                             int64_t param0,
+                             int64_t param1,
+                             int64_t param2) {
+    Exception<SizeT> e = {
+        .id = id,
+        .filename = {.base = reinterpret_cast<void*>(const_cast<char*>(filename)),
+                     .len = static_cast<SizeT>(__builtin_strlen(filename))},
+        .line = line,
+        .column = 0,
+        .function = {.base = reinterpret_cast<void*>(const_cast<char*>(function)),
+                     .len = static_cast<SizeT>(__builtin_strlen(function))},
+        .msg = {.base = reinterpret_cast<void*>(const_cast<char*>(msg)),
+                .len = static_cast<SizeT>(__builtin_strlen(msg))},
+    };
+    e.params[0] = param0;
+    e.params[1] = param1;
+    e.params[2] = param2;
+    __nac3_raise(reinterpret_cast<void*>(&e));
+    __builtin_unreachable();
+}
+}  // namespace
+
+/**
+ * @brief Raise an exception with location details (location in the IRRT source files).
+ * @param SizeT The runtime `size_t` type.
+ * @param id The ID of the exception to raise.
+ * @param msg A global constant C-string of the error message.
+ *
+ * `param0` to `param2` are optional format arguments of `msg`. They should be set to
+ * `NO_PARAM` to indicate they are unused.
+ */
+#define raise_exception(SizeT, id, msg, param0, param1, param2) \
+    _raise_exception_helper<SizeT>(id, __FILE__, __LINE__, __FUNCTION__, msg, param0, param1, param2)

nac3core/irrt/irrt/int_types.hpp

@@ -0,0 +1,27 @@
+#pragma once
+
+#if __STDC_VERSION__ >= 202000
+using int8_t = _BitInt(8);
+using uint8_t = unsigned _BitInt(8);
+using int32_t = _BitInt(32);
+using uint32_t = unsigned _BitInt(32);
+using int64_t = _BitInt(64);
+using uint64_t = unsigned _BitInt(64);
+#else
+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-type"
+using int8_t = _ExtInt(8);
+using uint8_t = unsigned _ExtInt(8);
+using int32_t = _ExtInt(32);
+using uint32_t = unsigned _ExtInt(32);
+using int64_t = _ExtInt(64);
+using uint64_t = unsigned _ExtInt(64);
+#pragma clang diagnostic pop
+
+#endif
+
+// NDArray indices are always `uint32_t`.
+using NDIndexInt = uint32_t;
+// The type of an index or a value describing the length of a range/slice is always `int32_t`.
+using SliceIndex = int32_t;

nac3core/irrt/irrt/list.hpp

@@ -0,0 +1,81 @@
+#pragma once
+
+#include "irrt/int_types.hpp"
+#include "irrt/math_util.hpp"
+
+extern "C" {
+// Handle list assignment and dropping part of the list when
+// both dest_step and src_step are +1.
+// - All the index must *not* be out-of-bound or negative,
+// - The end index is *inclusive*,
+// - The length of src and dest slice size should already
+// be checked: if dest.step == 1 then len(src) <= len(dest) else len(src) == len(dest)
+SliceIndex __nac3_list_slice_assign_var_size(SliceIndex dest_start,
+                                             SliceIndex dest_end,
+                                             SliceIndex dest_step,
+                                             void* dest_arr,
+                                             SliceIndex dest_arr_len,
+                                             SliceIndex src_start,
+                                             SliceIndex src_end,
+                                             SliceIndex src_step,
+                                             void* src_arr,
+                                             SliceIndex src_arr_len,
+                                             const SliceIndex size) {
+    /* if dest_arr_len == 0, do nothing since we do not support extending list */
+    if (dest_arr_len == 0)
+        return dest_arr_len;
+    /* if both step is 1, memmove directly, handle the dropping of the list, and shrink size */
+    if (src_step == dest_step && dest_step == 1) {
+        const SliceIndex src_len = (src_end >= src_start) ? (src_end - src_start + 1) : 0;
+        const SliceIndex dest_len = (dest_end >= dest_start) ? (dest_end - dest_start + 1) : 0;
+        if (src_len > 0) {
+            __builtin_memmove(static_cast<uint8_t*>(dest_arr) + dest_start * size,
+                              static_cast<uint8_t*>(src_arr) + src_start * size, src_len * size);
+        }
+        if (dest_len > 0) {
+            /* dropping */
+            __builtin_memmove(static_cast<uint8_t*>(dest_arr) + (dest_start + src_len) * size,
+                              static_cast<uint8_t*>(dest_arr) + (dest_end + 1) * size,
+                              (dest_arr_len - dest_end - 1) * size);
+        }
+        /* shrink size */
+        return dest_arr_len - (dest_len - src_len);
+    }
+    /* if two range overlaps, need alloca */
+    uint8_t need_alloca = (dest_arr == src_arr)
+                          && !(max(dest_start, dest_end) < min(src_start, src_end)
+                               || max(src_start, src_end) < min(dest_start, dest_end));
+    if (need_alloca) {
+        void* tmp = __builtin_alloca(src_arr_len * size);
+        __builtin_memcpy(tmp, src_arr, src_arr_len * size);
+        src_arr = tmp;
+    }
+    SliceIndex src_ind = src_start;
+    SliceIndex dest_ind = dest_start;
+    for (; (src_step > 0) ? (src_ind <= src_end) : (src_ind >= src_end); src_ind += src_step, dest_ind += dest_step) {
+        /* for constant optimization */
+        if (size == 1) {
+            __builtin_memcpy(static_cast<uint8_t*>(dest_arr) + dest_ind, static_cast<uint8_t*>(src_arr) + src_ind, 1);
+        } else if (size == 4) {
+            __builtin_memcpy(static_cast<uint8_t*>(dest_arr) + dest_ind * 4,
+                             static_cast<uint8_t*>(src_arr) + src_ind * 4, 4);
+        } else if (size == 8) {
+            __builtin_memcpy(static_cast<uint8_t*>(dest_arr) + dest_ind * 8,
+                             static_cast<uint8_t*>(src_arr) + src_ind * 8, 8);
+        } else {
+            /* memcpy for var size, cannot overlap after previous alloca */
+            __builtin_memcpy(static_cast<uint8_t*>(dest_arr) + dest_ind * size,
+                             static_cast<uint8_t*>(src_arr) + src_ind * size, size);
+        }
+    }
+    /* only dest_step == 1 can we shrink the dest list. */
+    /* size should be ensured prior to calling this function */
+    if (dest_step == 1 && dest_end >= dest_start) {
+        __builtin_memmove(static_cast<uint8_t*>(dest_arr) + dest_ind * size,
+                          static_cast<uint8_t*>(dest_arr) + (dest_end + 1) * size,
+                          (dest_arr_len - dest_end - 1) * size);
+        return dest_arr_len - (dest_end - dest_ind) - 1;
+    }
+    return dest_arr_len;
+}
+}  // extern "C"

nac3core/irrt/irrt/math.hpp

@@ -0,0 +1,93 @@
+#pragma once
+
+namespace {
+// adapted from GNU Scientific Library: https://git.savannah.gnu.org/cgit/gsl.git/tree/sys/pow_int.c
+// need to make sure `exp >= 0` before calling this function
+template<typename T>
+T __nac3_int_exp_impl(T base, T exp) {
+    T res = 1;
+    /* repeated squaring method */
+    do {
+        if (exp & 1) {
+            res *= base; /* for n odd */
+        }
+        exp >>= 1;
+        base *= base;
+    } while (exp);
+    return res;
+}
+}  // namespace
+
+#define DEF_nac3_int_exp_(T)                   \
+    T __nac3_int_exp_##T(T base, T exp) {      \
+        return __nac3_int_exp_impl(base, exp); \
+    }
+
+extern "C" {
+
+// Putting semicolons here to make clang-format not reformat this into
+// a stair shape.
+DEF_nac3_int_exp_(int32_t);
+DEF_nac3_int_exp_(int64_t);
+DEF_nac3_int_exp_(uint32_t);
+DEF_nac3_int_exp_(uint64_t);
+
+int32_t __nac3_isinf(double x) {
+    return __builtin_isinf(x);
+}
+
+int32_t __nac3_isnan(double x) {
+    return __builtin_isnan(x);
+}
+
+double tgamma(double arg);
+
+double __nac3_gamma(double z) {
+    // Handling for denormals
+    //     | x                 | Python gamma(x) | C tgamma(x) |
+    // --- | ----------------- | --------------- | ----------- |
+    // (1) | nan               | nan             | nan         |
+    // (2) | -inf              | -inf            | inf         |
+    // (3) | inf               | inf             | inf         |
+    // (4) | 0.0               | inf             | inf         |
+    // (5) | {-1.0, -2.0, ...} | inf             | nan         |
+
+    // (1)-(3)
+    if (__builtin_isinf(z) || __builtin_isnan(z)) {
+        return z;
+    }
+
+    double v = tgamma(z);
+
+    // (4)-(5)
+    return __builtin_isinf(v) || __builtin_isnan(v) ? __builtin_inf() : v;
+}
+
+double lgamma(double arg);
+
+double __nac3_gammaln(double x) {
+    // libm's handling of value overflows differs from scipy:
+    // - scipy: gammaln(-inf) -> -inf
+    // - libm : lgamma(-inf) -> inf
+
+    if (__builtin_isinf(x)) {
+        return x;
+    }
+
+    return lgamma(x);
+}
+
+double j0(double x);
+
+double __nac3_j0(double x) {
+    // libm's handling of value overflows differs from scipy:
+    // - scipy: j0(inf) -> nan
+    // - libm : j0(inf) -> 0.0
+
+    if (__builtin_isinf(x)) {
+        return __builtin_nan("");
+    }
+
+    return j0(x);
+}
+}  // namespace

nac3core/irrt/irrt/math_util.hpp

@@ -0,0 +1,13 @@
+#pragma once
+
+namespace {
+template<typename T>
+const T& max(const T& a, const T& b) {
+    return a > b ? a : b;
+}
+
+template<typename T>
+const T& min(const T& a, const T& b) {
+    return a > b ? b : a;
+}
+}  // namespace

nac3core/irrt/irrt/ndarray.hpp

@@ -0,0 +1,151 @@
+#pragma once
+
+#include "irrt/int_types.hpp"
+
+// TODO: To be deleted since NDArray with strides is done.
+
+namespace {
+template<typename SizeT>
+SizeT __nac3_ndarray_calc_size_impl(const SizeT* list_data, SizeT list_len, SizeT begin_idx, SizeT end_idx) {
+    __builtin_assume(end_idx <= list_len);
+
+    SizeT num_elems = 1;
+    for (SizeT i = begin_idx; i < end_idx; ++i) {
+        SizeT val = list_data[i];
+        __builtin_assume(val > 0);
+        num_elems *= val;
+    }
+    return num_elems;
+}
+
+template<typename SizeT>
+void __nac3_ndarray_calc_nd_indices_impl(SizeT index, const SizeT* dims, SizeT num_dims, NDIndexInt* idxs) {
+    SizeT stride = 1;
+    for (SizeT dim = 0; dim < num_dims; dim++) {
+        SizeT i = num_dims - dim - 1;
+        __builtin_assume(dims[i] > 0);
+        idxs[i] = (index / stride) % dims[i];
+        stride *= dims[i];
+    }
+}
+
+template<typename SizeT>
+SizeT __nac3_ndarray_flatten_index_impl(const SizeT* dims,
+                                        SizeT num_dims,
+                                        const NDIndexInt* indices,
+                                        SizeT num_indices) {
+    SizeT idx = 0;
+    SizeT stride = 1;
+    for (SizeT i = 0; i < num_dims; ++i) {
+        SizeT ri = num_dims - i - 1;
+        if (ri < num_indices) {
+            idx += stride * indices[ri];
+        }
+
+        __builtin_assume(dims[i] > 0);
+        stride *= dims[ri];
+    }
+    return idx;
+}
+
+template<typename SizeT>
+void __nac3_ndarray_calc_broadcast_impl(const SizeT* lhs_dims,
+                                        SizeT lhs_ndims,
+                                        const SizeT* rhs_dims,
+                                        SizeT rhs_ndims,
+                                        SizeT* out_dims) {
+    SizeT max_ndims = lhs_ndims > rhs_ndims ? lhs_ndims : rhs_ndims;
+
+    for (SizeT i = 0; i < max_ndims; ++i) {
+        const SizeT* lhs_dim_sz = i < lhs_ndims ? &lhs_dims[lhs_ndims - i - 1] : nullptr;
+        const SizeT* rhs_dim_sz = i < rhs_ndims ? &rhs_dims[rhs_ndims - i - 1] : nullptr;
+        SizeT* out_dim = &out_dims[max_ndims - i - 1];
+
+        if (lhs_dim_sz == nullptr) {
+            *out_dim = *rhs_dim_sz;
+        } else if (rhs_dim_sz == nullptr) {
+            *out_dim = *lhs_dim_sz;
+        } else if (*lhs_dim_sz == 1) {
+            *out_dim = *rhs_dim_sz;
+        } else if (*rhs_dim_sz == 1) {
+            *out_dim = *lhs_dim_sz;
+        } else if (*lhs_dim_sz == *rhs_dim_sz) {
+            *out_dim = *lhs_dim_sz;
+        } else {
+            __builtin_unreachable();
+        }
+    }
+}
+
+template<typename SizeT>
+void __nac3_ndarray_calc_broadcast_idx_impl(const SizeT* src_dims,
+                                            SizeT src_ndims,
+                                            const NDIndexInt* in_idx,
+                                            NDIndexInt* out_idx) {
+    for (SizeT i = 0; i < src_ndims; ++i) {
+        SizeT src_i = src_ndims - i - 1;
+        out_idx[src_i] = src_dims[src_i] == 1 ? 0 : in_idx[src_i];
+    }
+}
+}  // namespace
+
+extern "C" {
+uint32_t __nac3_ndarray_calc_size(const uint32_t* list_data, uint32_t list_len, uint32_t begin_idx, uint32_t end_idx) {
+    return __nac3_ndarray_calc_size_impl(list_data, list_len, begin_idx, end_idx);
+}
+
+uint64_t
+__nac3_ndarray_calc_size64(const uint64_t* list_data, uint64_t list_len, uint64_t begin_idx, uint64_t end_idx) {
+    return __nac3_ndarray_calc_size_impl(list_data, list_len, begin_idx, end_idx);
+}
+
+void __nac3_ndarray_calc_nd_indices(uint32_t index, const uint32_t* dims, uint32_t num_dims, NDIndexInt* idxs) {
+    __nac3_ndarray_calc_nd_indices_impl(index, dims, num_dims, idxs);
+}
+
+void __nac3_ndarray_calc_nd_indices64(uint64_t index, const uint64_t* dims, uint64_t num_dims, NDIndexInt* idxs) {
+    __nac3_ndarray_calc_nd_indices_impl(index, dims, num_dims, idxs);
+}
+
+uint32_t
+__nac3_ndarray_flatten_index(const uint32_t* dims, uint32_t num_dims, const NDIndexInt* indices, uint32_t num_indices) {
+    return __nac3_ndarray_flatten_index_impl(dims, num_dims, indices, num_indices);
+}
+
+uint64_t __nac3_ndarray_flatten_index64(const uint64_t* dims,
+                                        uint64_t num_dims,
+                                        const NDIndexInt* indices,
+                                        uint64_t num_indices) {
+    return __nac3_ndarray_flatten_index_impl(dims, num_dims, indices, num_indices);
+}
+
+void __nac3_ndarray_calc_broadcast(const uint32_t* lhs_dims,
+                                   uint32_t lhs_ndims,
+                                   const uint32_t* rhs_dims,
+                                   uint32_t rhs_ndims,
+                                   uint32_t* out_dims) {
+    return __nac3_ndarray_calc_broadcast_impl(lhs_dims, lhs_ndims, rhs_dims, rhs_ndims, out_dims);
+}
+
+void __nac3_ndarray_calc_broadcast64(const uint64_t* lhs_dims,
+                                     uint64_t lhs_ndims,
+                                     const uint64_t* rhs_dims,
+                                     uint64_t rhs_ndims,
+                                     uint64_t* out_dims) {
+    return __nac3_ndarray_calc_broadcast_impl(lhs_dims, lhs_ndims, rhs_dims, rhs_ndims, out_dims);
+}
+
+void __nac3_ndarray_calc_broadcast_idx(const uint32_t* src_dims,
+                                       uint32_t src_ndims,
+                                       const NDIndexInt* in_idx,
+                                       NDIndexInt* out_idx) {
+    __nac3_ndarray_calc_broadcast_idx_impl(src_dims, src_ndims, in_idx, out_idx);
+}
+
+void __nac3_ndarray_calc_broadcast_idx64(const uint64_t* src_dims,
+                                         uint64_t src_ndims,
+                                         const NDIndexInt* in_idx,
+                                         NDIndexInt* out_idx) {
+    __nac3_ndarray_calc_broadcast_idx_impl(src_dims, src_ndims, in_idx, out_idx);
+}
+}  // namespace

nac3core/irrt/irrt/ndarray/basic.hpp

@@ -0,0 +1,342 @@
+#pragma once
+
+#include "irrt/debug.hpp"
+#include "irrt/exception.hpp"
+#include "irrt/int_types.hpp"
+#include "irrt/ndarray/def.hpp"
+
+namespace {
+namespace ndarray {
+namespace basic {
+/**
+ * @brief Assert that `shape` does not contain negative dimensions.
+ *
+ * @param ndims Number of dimensions in `shape`
+ * @param shape The shape to check on
+ */
+template<typename SizeT>
+void assert_shape_no_negative(SizeT ndims, const SizeT* shape) {
+    for (SizeT axis = 0; axis < ndims; axis++) {
+        if (shape[axis] < 0) {
+            raise_exception(SizeT, EXN_VALUE_ERROR,
+                            "negative dimensions are not allowed; axis {0} "
+                            "has dimension {1}",
+                            axis, shape[axis], NO_PARAM);
+        }
+    }
+}
+
+/**
+ * @brief Assert that two shapes are the same in the context of writing output to an ndarray.
+ */
+template<typename SizeT>
+void assert_output_shape_same(SizeT ndarray_ndims,
+                              const SizeT* ndarray_shape,
+                              SizeT output_ndims,
+                              const SizeT* output_shape) {
+    if (ndarray_ndims != output_ndims) {
+        // There is no corresponding NumPy error message like this.
+        raise_exception(SizeT, EXN_VALUE_ERROR, "Cannot write output of ndims {0} to an ndarray with ndims {1}",
+                        output_ndims, ndarray_ndims, NO_PARAM);
+    }
+
+    for (SizeT axis = 0; axis < ndarray_ndims; axis++) {
+        if (ndarray_shape[axis] != output_shape[axis]) {
+            // There is no corresponding NumPy error message like this.
+            raise_exception(SizeT, EXN_VALUE_ERROR,
+                            "Mismatched dimensions on axis {0}, output has "
+                            "dimension {1}, but destination ndarray has dimension {2}.",
+                            axis, output_shape[axis], ndarray_shape[axis]);
+        }
+    }
+}
+
+/**
+ * @brief Return the number of elements of an ndarray given its shape.
+ *
+ * @param ndims Number of dimensions in `shape`
+ * @param shape The shape of the ndarray
+ */
+template<typename SizeT>
+SizeT calc_size_from_shape(SizeT ndims, const SizeT* shape) {
+    SizeT size = 1;
+    for (SizeT axis = 0; axis < ndims; axis++)
+        size *= shape[axis];
+    return size;
+}
+
+/**
+ * @brief Compute the array indices of the `nth` (0-based) element of an ndarray given only its shape.
+ *
+ * @param ndims Number of elements in `shape` and `indices`
+ * @param shape The shape of the ndarray
+ * @param indices The returned indices indexing the ndarray with shape `shape`.
+ * @param nth The index of the element of interest.
+ */
+template<typename SizeT>
+void set_indices_by_nth(SizeT ndims, const SizeT* shape, SizeT* indices, SizeT nth) {
+    for (SizeT i = 0; i < ndims; i++) {
+        SizeT axis = ndims - i - 1;
+        SizeT dim = shape[axis];
+
+        indices[axis] = nth % dim;
+        nth /= dim;
+    }
+}
+
+/**
+ * @brief Return the number of elements of an `ndarray`
+ *
+ * This function corresponds to `<an_ndarray>.size`
+ */
+template<typename SizeT>
+SizeT size(const NDArray<SizeT>* ndarray) {
+    return calc_size_from_shape(ndarray->ndims, ndarray->shape);
+}
+
+/**
+ * @brief Return of the number of its content of an `ndarray`.
+ *
+ * This function corresponds to `<an_ndarray>.nbytes`.
+ */
+template<typename SizeT>
+SizeT nbytes(const NDArray<SizeT>* ndarray) {
+    return size(ndarray) * ndarray->itemsize;
+}
+
+/**
+ * @brief Get the `len()` of an ndarray, and asserts that `ndarray` is a sized object.
+ *
+ * This function corresponds to `<an_ndarray>.__len__`.
+ *
+ * @param dst_length The length.
+ */
+template<typename SizeT>
+SizeT len(const NDArray<SizeT>* ndarray) {
+    if (ndarray->ndims != 0) {
+        return ndarray->shape[0];
+    }
+
+    // numpy prohibits `__len__` on unsized objects
+    raise_exception(SizeT, EXN_TYPE_ERROR, "len() of unsized object", NO_PARAM, NO_PARAM, NO_PARAM);
+    __builtin_unreachable();
+}
+
+/**
+ * @brief Return a boolean indicating if `ndarray` is (C-)contiguous.
+ *
+ * You may want to see ndarray's rules for C-contiguity:
+ * https://github.com/numpy/numpy/blob/df256d0d2f3bc6833699529824781c58f9c6e697/numpy/core/src/multiarray/flagsobject.c#L95C1-L99C45
+ */
+template<typename SizeT>
+bool is_c_contiguous(const NDArray<SizeT>* ndarray) {
+    // References:
+    // - tinynumpy's implementation:
+    // https://github.com/wadetb/tinynumpy/blob/0d23d22e07062ffab2afa287374c7b366eebdda1/tinynumpy/tinynumpy.py#L102
+    // - ndarray's flags["C_CONTIGUOUS"]:
+    // https://numpy.org/doc/stable/reference/generated/numpy.ndarray.flags.html#numpy.ndarray.flags
+    // - ndarray's rules for C-contiguity:
+    // https://github.com/numpy/numpy/blob/df256d0d2f3bc6833699529824781c58f9c6e697/numpy/core/src/multiarray/flagsobject.c#L95C1-L99C45
+
+    // From
+    // https://github.com/numpy/numpy/blob/df256d0d2f3bc6833699529824781c58f9c6e697/numpy/core/src/multiarray/flagsobject.c#L95C1-L99C45:
+    //
+    // The traditional rule is that for an array to be flagged as C contiguous,
+    // the following must hold:
+    //
+    // strides[-1] == itemsize
+    // strides[i] == shape[i+1] * strides[i + 1]
+    // [...]
+    // According to these rules, a 0- or 1-dimensional array is either both
+    // C- and F-contiguous, or neither; and an array with 2+ dimensions
+    // can be C- or F- contiguous, or neither, but not both. Though there
+    // there are exceptions for arrays with zero or one item, in the first
+    // case the check is relaxed up to and including the first dimension
+    // with shape[i] == 0. In the second case `strides == itemsize` will
+    // can be true for all dimensions and both flags are set.
+
+    if (ndarray->ndims == 0) {
+        return true;
+    }
+
+    if (ndarray->strides[ndarray->ndims - 1] != ndarray->itemsize) {
+        return false;
+    }
+
+    for (SizeT i = 1; i < ndarray->ndims; i++) {
+        SizeT axis_i = ndarray->ndims - i - 1;
+        if (ndarray->strides[axis_i] != ndarray->shape[axis_i + 1] * ndarray->strides[axis_i + 1]) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+/**
+ * @brief Return the pointer to the element indexed by `indices` along the ndarray's axes.
+ *
+ * This function does no bound check.
+ */
+template<typename SizeT>
+void* get_pelement_by_indices(const NDArray<SizeT>* ndarray, const SizeT* indices) {
+    void* element = ndarray->data;
+    for (SizeT dim_i = 0; dim_i < ndarray->ndims; dim_i++)
+        element = static_cast<uint8_t*>(element) + indices[dim_i] * ndarray->strides[dim_i];
+    return element;
+}
+
+/**
+ * @brief Return the pointer to the nth (0-based) element of `ndarray` in flattened view.
+ *
+ * This function does no bound check.
+ */
+template<typename SizeT>
+void* get_nth_pelement(const NDArray<SizeT>* ndarray, SizeT nth) {
+    void* element = ndarray->data;
+    for (SizeT i = 0; i < ndarray->ndims; i++) {
+        SizeT axis = ndarray->ndims - i - 1;
+        SizeT dim = ndarray->shape[axis];
+        element = static_cast<uint8_t*>(element) + ndarray->strides[axis] * (nth % dim);
+        nth /= dim;
+    }
+    return element;
+}
+
+/**
+ * @brief Update the strides of an ndarray given an ndarray `shape` to be contiguous.
+ *
+ * You might want to read https://ajcr.net/stride-guide-part-1/.
+ */
+template<typename SizeT>
+void set_strides_by_shape(NDArray<SizeT>* ndarray) {
+    SizeT stride_product = 1;
+    for (SizeT i = 0; i < ndarray->ndims; i++) {
+        SizeT axis = ndarray->ndims - i - 1;
+        ndarray->strides[axis] = stride_product * ndarray->itemsize;
+        stride_product *= ndarray->shape[axis];
+    }
+}
+
+/**
+ * @brief Set an element in `ndarray`.
+ *
+ * @param pelement Pointer to the element in `ndarray` to be set.
+ * @param pvalue Pointer to the value `pelement` will be set to.
+ */
+template<typename SizeT>
+void set_pelement_value(NDArray<SizeT>* ndarray, void* pelement, const void* pvalue) {
+    __builtin_memcpy(pelement, pvalue, ndarray->itemsize);
+}
+
+/**
+ * @brief Copy data from one ndarray to another of the exact same size and itemsize.
+ *
+ * Both ndarrays will be viewed in their flatten views when copying the elements.
+ */
+template<typename SizeT>
+void copy_data(const NDArray<SizeT>* src_ndarray, NDArray<SizeT>* dst_ndarray) {
+    // TODO: Make this faster with memcpy when we see a contiguous segment.
+    // TODO: Handle overlapping.
+
+    debug_assert_eq(SizeT, src_ndarray->itemsize, dst_ndarray->itemsize);
+
+    for (SizeT i = 0; i < size(src_ndarray); i++) {
+        auto src_element = ndarray::basic::get_nth_pelement(src_ndarray, i);
+        auto dst_element = ndarray::basic::get_nth_pelement(dst_ndarray, i);
+        ndarray::basic::set_pelement_value(dst_ndarray, dst_element, src_element);
+    }
+}
+}  // namespace basic
+}  // namespace ndarray
+}  // namespace
+
+extern "C" {
+using namespace ndarray::basic;
+
+void __nac3_ndarray_util_assert_shape_no_negative(int32_t ndims, int32_t* shape) {
+    assert_shape_no_negative(ndims, shape);
+}
+
+void __nac3_ndarray_util_assert_shape_no_negative64(int64_t ndims, int64_t* shape) {
+    assert_shape_no_negative(ndims, shape);
+}
+
+void __nac3_ndarray_util_assert_output_shape_same(int32_t ndarray_ndims,
+                                                  const int32_t* ndarray_shape,
+                                                  int32_t output_ndims,
+                                                  const int32_t* output_shape) {
+    assert_output_shape_same(ndarray_ndims, ndarray_shape, output_ndims, output_shape);
+}
+
+void __nac3_ndarray_util_assert_output_shape_same64(int64_t ndarray_ndims,
+                                                    const int64_t* ndarray_shape,
+                                                    int64_t output_ndims,
+                                                    const int64_t* output_shape) {
+    assert_output_shape_same(ndarray_ndims, ndarray_shape, output_ndims, output_shape);
+}
+
+uint32_t __nac3_ndarray_size(NDArray<int32_t>* ndarray) {
+    return size(ndarray);
+}
+
+uint64_t __nac3_ndarray_size64(NDArray<int64_t>* ndarray) {
+    return size(ndarray);
+}
+
+uint32_t __nac3_ndarray_nbytes(NDArray<int32_t>* ndarray) {
+    return nbytes(ndarray);
+}
+
+uint64_t __nac3_ndarray_nbytes64(NDArray<int64_t>* ndarray) {
+    return nbytes(ndarray);
+}
+
+int32_t __nac3_ndarray_len(NDArray<int32_t>* ndarray) {
+    return len(ndarray);
+}
+
+int64_t __nac3_ndarray_len64(NDArray<int64_t>* ndarray) {
+    return len(ndarray);
+}
+
+bool __nac3_ndarray_is_c_contiguous(NDArray<int32_t>* ndarray) {
+    return is_c_contiguous(ndarray);
+}
+
+bool __nac3_ndarray_is_c_contiguous64(NDArray<int64_t>* ndarray) {
+    return is_c_contiguous(ndarray);
+}
+
+void* __nac3_ndarray_get_nth_pelement(const NDArray<int32_t>* ndarray, int32_t nth) {
+    return get_nth_pelement(ndarray, nth);
+}
+
+void* __nac3_ndarray_get_nth_pelement64(const NDArray<int64_t>* ndarray, int64_t nth) {
+    return get_nth_pelement(ndarray, nth);
+}
+
+void* __nac3_ndarray_get_pelement_by_indices(const NDArray<int32_t>* ndarray, int32_t* indices) {
+    return get_pelement_by_indices(ndarray, indices);
+}
+
+void* __nac3_ndarray_get_pelement_by_indices64(const NDArray<int64_t>* ndarray, int64_t* indices) {
+    return get_pelement_by_indices(ndarray, indices);
+}
+
+void __nac3_ndarray_set_strides_by_shape(NDArray<int32_t>* ndarray) {
+    set_strides_by_shape(ndarray);
+}
+
+void __nac3_ndarray_set_strides_by_shape64(NDArray<int64_t>* ndarray) {
+    set_strides_by_shape(ndarray);
+}
+
+void __nac3_ndarray_copy_data(NDArray<int32_t>* src_ndarray, NDArray<int32_t>* dst_ndarray) {
+    copy_data(src_ndarray, dst_ndarray);
+}
+
+void __nac3_ndarray_copy_data64(NDArray<int64_t>* src_ndarray, NDArray<int64_t>* dst_ndarray) {
+    copy_data(src_ndarray, dst_ndarray);
+}
+}

nac3core/irrt/irrt/ndarray/def.hpp

@@ -0,0 +1,51 @@
+#pragma once
+
+#include "irrt/int_types.hpp"
+
+namespace {
+/**
+ * @brief The NDArray object
+ *
+ * Official numpy implementation:
+ * https://github.com/numpy/numpy/blob/735a477f0bc2b5b84d0e72d92f224bde78d4e069/doc/source/reference/c-api/types-and-structures.rst#pyarrayinterface
+ *
+ * Note that this implementation is based on `PyArrayInterface` rather of `PyArrayObject`. The
+ * difference between `PyArrayInterface` and `PyArrayObject` (relevant to our implementation) is
+ * that `PyArrayInterface` *has* `itemsize` and uses `void*` for its `data`, whereas `PyArrayObject`
+ * does not require `itemsize` (probably using `strides[-1]` instead) and uses `char*` for its
+ * `data`. There are also minor differences in the struct layout.
+ */
+template<typename SizeT>
+struct NDArray {
+    /**
+     * @brief The number of bytes of a single element in `data`.
+     */
+    SizeT itemsize;
+
+    /**
+     * @brief The number of dimensions of this shape.
+     */
+    SizeT ndims;
+
+    /**
+     * @brief The NDArray shape, with length equal to `ndims`.
+     *
+     * Note that it may contain 0.
+     */
+    SizeT* shape;
+
+    /**
+     * @brief Array strides, with length equal to `ndims`
+     *
+     * The stride values are in units of bytes, not number of elements.
+     *
+     * Note that `strides` can have negative values or contain 0.
+     */
+    SizeT* strides;
+
+    /**
+     * @brief The underlying data this `ndarray` is pointing to.
+     */
+    void* data;
+};
+}  // namespace

nac3core/irrt/irrt/ndarray/indexing.hpp

@@ -0,0 +1,220 @@
+#pragma once
+
+#include "irrt/exception.hpp"
+#include "irrt/int_types.hpp"
+#include "irrt/ndarray/basic.hpp"
+#include "irrt/ndarray/def.hpp"
+#include "irrt/range.hpp"
+#include "irrt/slice.hpp"
+
+namespace {
+typedef uint8_t NDIndexType;
+
+/**
+ * @brief A single element index
+ *
+ * `data` points to a `int32_t`.
+ */
+const NDIndexType ND_INDEX_TYPE_SINGLE_ELEMENT = 0;
+
+/**
+ * @brief A slice index
+ *
+ * `data` points to a `Slice<int32_t>`.
+ */
+const NDIndexType ND_INDEX_TYPE_SLICE = 1;
+
+/**
+ * @brief `np.newaxis` / `None`
+ *
+ * `data` is unused.
+ */
+const NDIndexType ND_INDEX_TYPE_NEWAXIS = 2;
+
+/**
+ * @brief `Ellipsis` / `...`
+ *
+ * `data` is unused.
+ */
+const NDIndexType ND_INDEX_TYPE_ELLIPSIS = 3;
+
+/**
+ * @brief An index used in ndarray indexing
+ *
+ * That is:
+ * ```
+ * my_ndarray[::-1, 3, ..., np.newaxis]
+ *            ^^^^  ^  ^^^  ^^^^^^^^^^ each of these is represented by an NDIndex.
+ * ```
+ */
+struct NDIndex {
+    /**
+     * @brief Enum tag to specify the type of index.
+     *
+     * Please see the comment of each enum constant.
+     */
+    NDIndexType type;
+
+    /**
+     * @brief The accompanying data associated with `type`.
+     *
+     * Please see the comment of each enum constant.
+     */
+    uint8_t* data;
+};
+}  // namespace
+
+namespace {
+namespace ndarray {
+namespace indexing {
+/**
+ * @brief Perform ndarray "basic indexing" (https://numpy.org/doc/stable/user/basics.indexing.html#basic-indexing)
+ *
+ * This function is very similar to performing `dst_ndarray = src_ndarray[indices]` in Python.
+ *
+ * This function also does proper assertions on `indices` to check for out of bounds access and more.
+ *
+ * # Notes on `dst_ndarray`
+ * The caller is responsible for allocating space for the resulting ndarray.
+ * Here is what this function expects from `dst_ndarray` when called:
+ *   - `dst_ndarray->data` does not have to be initialized.
+ *   - `dst_ndarray->itemsize` does not have to be initialized.
+ *   - `dst_ndarray->ndims` must be initialized, and it must be equal to the expected `ndims` of the `dst_ndarray` after
+ *       indexing `src_ndarray` with `indices`.
+ *   - `dst_ndarray->shape` must be allocated, through it can contain uninitialized values.
+ *   - `dst_ndarray->strides` must be allocated, through it can contain uninitialized values.
+ * When this function call ends:
+ *   - `dst_ndarray->data` is set to `src_ndarray->data`.
+ *   - `dst_ndarray->itemsize` is set to `src_ndarray->itemsize`.
+ *   - `dst_ndarray->ndims` is unchanged.
+ *   - `dst_ndarray->shape` is updated according to how `src_ndarray` is indexed.
+ *   - `dst_ndarray->strides` is updated accordingly by how ndarray indexing works.
+ *
+ * @param indices indices to index `src_ndarray`, ordered in the same way you would write them in Python.
+ * @param src_ndarray The NDArray to be indexed.
+ * @param dst_ndarray The resulting NDArray after indexing. Further details in the comments above,
+ */
+template<typename SizeT>
+void index(SizeT num_indices, const NDIndex* indices, const NDArray<SizeT>* src_ndarray, NDArray<SizeT>* dst_ndarray) {
+    // Validate `indices`.
+
+    // Expected value of `dst_ndarray->ndims`.
+    SizeT expected_dst_ndims = src_ndarray->ndims;
+    // To check for "too many indices for array: array is ?-dimensional, but ? were indexed"
+    SizeT num_indexed = 0;
+    // There may be ellipsis `...` in `indices`. There can only be 0 or 1 ellipsis.
+    SizeT num_ellipsis = 0;
+
+    for (SizeT i = 0; i < num_indices; i++) {
+        if (indices[i].type == ND_INDEX_TYPE_SINGLE_ELEMENT) {
+            expected_dst_ndims--;
+            num_indexed++;
+        } else if (indices[i].type == ND_INDEX_TYPE_SLICE) {
+            num_indexed++;
+        } else if (indices[i].type == ND_INDEX_TYPE_NEWAXIS) {
+            expected_dst_ndims++;
+        } else if (indices[i].type == ND_INDEX_TYPE_ELLIPSIS) {
+            num_ellipsis++;
+            if (num_ellipsis > 1) {
+                raise_exception(SizeT, EXN_INDEX_ERROR, "an index can only have a single ellipsis ('...')", NO_PARAM,
+                                NO_PARAM, NO_PARAM);
+            }
+        } else {
+            __builtin_unreachable();
+        }
+    }
+
+    debug_assert_eq(SizeT, expected_dst_ndims, dst_ndarray->ndims);
+
+    if (src_ndarray->ndims - num_indexed < 0) {
+        raise_exception(SizeT, EXN_INDEX_ERROR,
+                        "too many indices for array: array is {0}-dimensional, "
+                        "but {1} were indexed",
+                        src_ndarray->ndims, num_indices, NO_PARAM);
+    }
+
+    dst_ndarray->data = src_ndarray->data;
+    dst_ndarray->itemsize = src_ndarray->itemsize;
+
+    // Reference code:
+    // https://github.com/wadetb/tinynumpy/blob/0d23d22e07062ffab2afa287374c7b366eebdda1/tinynumpy/tinynumpy.py#L652
+    SizeT src_axis = 0;
+    SizeT dst_axis = 0;
+
+    for (int32_t i = 0; i < num_indices; i++) {
+        const NDIndex* index = &indices[i];
+        if (index->type == ND_INDEX_TYPE_SINGLE_ELEMENT) {
+            SizeT input = (SizeT) * ((int32_t*)index->data);
+
+            SizeT k = slice::resolve_index_in_length(src_ndarray->shape[src_axis], input);
+            if (k == -1) {
+                raise_exception(SizeT, EXN_INDEX_ERROR,
+                                "index {0} is out of bounds for axis {1} "
+                                "with size {2}",
+                                input, src_axis, src_ndarray->shape[src_axis]);
+            }
+
+            dst_ndarray->data = static_cast<uint8_t*>(dst_ndarray->data) + k * src_ndarray->strides[src_axis];
+
+            src_axis++;
+        } else if (index->type == ND_INDEX_TYPE_SLICE) {
+            Slice<int32_t>* slice = (Slice<int32_t>*)index->data;
+
+            Range<int32_t> range = slice->indices_checked<SizeT>(src_ndarray->shape[src_axis]);
+
+            dst_ndarray->data = static_cast<uint8_t*>(dst_ndarray->data) + (SizeT)range.start * src_ndarray->strides[src_axis];
+            dst_ndarray->strides[dst_axis] = ((SizeT)range.step) * src_ndarray->strides[src_axis];
+            dst_ndarray->shape[dst_axis] = (SizeT)range.len<SizeT>();
+
+            dst_axis++;
+            src_axis++;
+        } else if (index->type == ND_INDEX_TYPE_NEWAXIS) {
+            dst_ndarray->strides[dst_axis] = 0;
+            dst_ndarray->shape[dst_axis] = 1;
+
+            dst_axis++;
+        } else if (index->type == ND_INDEX_TYPE_ELLIPSIS) {
+            // The number of ':' entries this '...' implies.
+            SizeT ellipsis_size = src_ndarray->ndims - num_indexed;
+
+            for (SizeT j = 0; j < ellipsis_size; j++) {
+                dst_ndarray->strides[dst_axis] = src_ndarray->strides[src_axis];
+                dst_ndarray->shape[dst_axis] = src_ndarray->shape[src_axis];
+
+                dst_axis++;
+                src_axis++;
+            }
+        } else {
+            __builtin_unreachable();
+        }
+    }
+
+    for (; dst_axis < dst_ndarray->ndims; dst_axis++, src_axis++) {
+        dst_ndarray->shape[dst_axis] = src_ndarray->shape[src_axis];
+        dst_ndarray->strides[dst_axis] = src_ndarray->strides[src_axis];
+    }
+
+    debug_assert_eq(SizeT, src_ndarray->ndims, src_axis);
+    debug_assert_eq(SizeT, dst_ndarray->ndims, dst_axis);
+}
+}  // namespace indexing
+}  // namespace ndarray
+}  // namespace
+
+extern "C" {
+using namespace ndarray::indexing;
+
+void __nac3_ndarray_index(int32_t num_indices,
+                          NDIndex* indices,
+                          NDArray<int32_t>* src_ndarray,
+                          NDArray<int32_t>* dst_ndarray) {
+    index(num_indices, indices, src_ndarray, dst_ndarray);
+}
+
+void __nac3_ndarray_index64(int64_t num_indices,
+                            NDIndex* indices,
+                            NDArray<int64_t>* src_ndarray,
+                            NDArray<int64_t>* dst_ndarray) {
+    index(num_indices, indices, src_ndarray, dst_ndarray);
+}
+}

nac3core/irrt/irrt/ndarray/iter.hpp

@@ -0,0 +1,146 @@
+#pragma once
+
+#include "irrt/int_types.hpp"
+#include "irrt/ndarray/def.hpp"
+
+namespace {
+/**
+ * @brief Helper struct to enumerate through an ndarray *efficiently*.
+ *
+ * Example usage (in pseudo-code):
+ * ```
+ * // Suppose my_ndarray has been initialized, with shape [2, 3] and dtype `double`
+ * NDIter nditer;
+ * nditer.initialize(my_ndarray);
+ * while (nditer.has_element()) {
+ *    // This body is run 6 (= my_ndarray.size) times.
+ *
+ *    // [0, 0] -> [0, 1] -> [0, 2] -> [1, 0] -> [1, 1] -> [1, 2] -> end
+ *    print(nditer.indices);
+ *
+ *    // 0 -> 1 -> 2 -> 3 -> 4 -> 5
+ *    print(nditer.nth);
+ *
+ *    // <1st element> -> <2nd element> -> ... -> <6th element> -> end
+ *    print(*((double *) nditer.element))
+ *
+ *    nditer.next(); // Go to next element.
+ * }
+ * ```
+ *
+ * Interesting cases:
+ * - If `my_ndarray.ndims` == 0, there is one iteration.
+ * - If `my_ndarray.shape` contains zeroes, there are no iterations.
+ */
+template<typename SizeT>
+struct NDIter {
+    // Information about the ndarray being iterated over.
+    SizeT ndims;
+    SizeT* shape;
+    SizeT* strides;
+
+    /**
+     * @brief The current indices.
+     *
+     * Must be allocated by the caller.
+     */
+    SizeT* indices;
+
+    /**
+     * @brief The nth (0-based) index of the current indices.
+     *
+     * Initially this is 0.
+     */
+    SizeT nth;
+
+    /**
+     * @brief Pointer to the current element.
+     *
+     * Initially this points to first element of the ndarray.
+     */
+    void* element;
+
+    /**
+     * @brief Cache for the product of shape.
+     *
+     * Could be 0 if `shape` has 0s in it.
+     */
+    SizeT size;
+
+    void initialize(SizeT ndims, SizeT* shape, SizeT* strides, void* element, SizeT* indices) {
+        this->ndims = ndims;
+        this->shape = shape;
+        this->strides = strides;
+
+        this->indices = indices;
+        this->element = element;
+
+        // Compute size
+        this->size = 1;
+        for (SizeT i = 0; i < ndims; i++) {
+            this->size *= shape[i];
+        }
+
+        // `indices` starts on all 0s.
+        for (SizeT axis = 0; axis < ndims; axis++)
+            indices[axis] = 0;
+        nth = 0;
+    }
+
+    void initialize_by_ndarray(NDArray<SizeT>* ndarray, SizeT* indices) {
+        // NOTE: ndarray->data is pointing to the first element, and `NDIter`'s `element` should also point to the first
+        // element as well.
+        this->initialize(ndarray->ndims, ndarray->shape, ndarray->strides, ndarray->data, indices);
+    }
+
+    // Is the current iteration valid?
+    // If true, then `element`, `indices` and `nth` contain details about the current element.
+    bool has_element() { return nth < size; }
+
+    // Go to the next element.
+    void next() {
+        for (SizeT i = 0; i < ndims; i++) {
+            SizeT axis = ndims - i - 1;
+            indices[axis]++;
+            if (indices[axis] >= shape[axis]) {
+                indices[axis] = 0;
+
+                // TODO: There is something called backstrides to speedup iteration.
+                // See https://ajcr.net/stride-guide-part-1/, and
+                // https://docs.scipy.org/doc/numpy-1.13.0/reference/c-api.types-and-structures.html#c.PyArrayIterObject.PyArrayIterObject.backstrides.
+                element = static_cast<void*>(reinterpret_cast<uint8_t*>(element) - strides[axis] * (shape[axis] - 1));
+            } else {
+                element = static_cast<void*>(reinterpret_cast<uint8_t*>(element) + strides[axis]);
+                break;
+            }
+        }
+        nth++;
+    }
+};
+}  // namespace
+
+extern "C" {
+void __nac3_nditer_initialize(NDIter<int32_t>* iter, NDArray<int32_t>* ndarray, int32_t* indices) {
+    iter->initialize_by_ndarray(ndarray, indices);
+}
+
+void __nac3_nditer_initialize64(NDIter<int64_t>* iter, NDArray<int64_t>* ndarray, int64_t* indices) {
+    iter->initialize_by_ndarray(ndarray, indices);
+}
+
+bool __nac3_nditer_has_element(NDIter<int32_t>* iter) {
+    return iter->has_element();
+}
+
+bool __nac3_nditer_has_element64(NDIter<int64_t>* iter) {
+    return iter->has_element();
+}
+
+void __nac3_nditer_next(NDIter<int32_t>* iter) {
+    iter->next();
+}
+
+void __nac3_nditer_next64(NDIter<int64_t>* iter) {
+    iter->next();
+}
+}

nac3core/irrt/irrt/range.hpp

@@ -0,0 +1,47 @@
+#pragma once
+
+#include "irrt/debug.hpp"
+#include "irrt/int_types.hpp"
+
+namespace {
+namespace range {
+template<typename T>
+T len(T start, T stop, T step) {
+    // Reference:
+    // https://github.com/python/cpython/blob/9dbd12375561a393eaec4b21ee4ac568a407cdb0/Objects/rangeobject.c#L933
+    if (step > 0 && start < stop)
+        return 1 + (stop - 1 - start) / step;
+    else if (step < 0 && start > stop)
+        return 1 + (start - 1 - stop) / (-step);
+    else
+        return 0;
+}
+}  // namespace range
+
+/**
+ * @brief A Python range.
+ */
+template<typename T>
+struct Range {
+    T start;
+    T stop;
+    T step;
+
+    /**
+     * @brief Calculate the `len()` of this range.
+     */
+    template<typename SizeT>
+    T len() {
+        debug_assert(SizeT, step != 0);
+        return range::len(start, stop, step);
+    }
+};
+}  // namespace
+
+extern "C" {
+using namespace range;
+
+SliceIndex __nac3_range_slice_len(const SliceIndex start, const SliceIndex end, const SliceIndex step) {
+    return len(start, end, step);
+}
+}

nac3core/irrt/irrt/slice.hpp

@@ -0,0 +1,156 @@
+#pragma once
+
+#include "irrt/debug.hpp"
+#include "irrt/exception.hpp"
+#include "irrt/int_types.hpp"
+#include "irrt/math_util.hpp"
+#include "irrt/range.hpp"
+
+namespace {
+namespace slice {
+/**
+ * @brief Resolve a possibly negative index in a list of a known length.
+ *
+ * Returns -1 if the resolved index is out of the list's bounds.
+ */
+template<typename T>
+T resolve_index_in_length(T length, T index) {
+    T resolved = index < 0 ? length + index : index;
+    if (0 <= resolved && resolved < length) {
+        return resolved;
+    } else {
+        return -1;
+    }
+}
+
+/**
+ * @brief Resolve a slice as a range.
+ *
+ * This is equivalent to `range(*slice(start, stop, step).indices(length))` in Python.
+ */
+template<typename T>
+void indices(bool start_defined,
+             T start,
+             bool stop_defined,
+             T stop,
+             bool step_defined,
+             T step,
+             T length,
+             T* range_start,
+             T* range_stop,
+             T* range_step) {
+    // Reference: https://github.com/python/cpython/blob/main/Objects/sliceobject.c#L388
+    *range_step = step_defined ? step : 1;
+    bool step_is_negative = *range_step < 0;
+
+    T lower, upper;
+    if (step_is_negative) {
+        lower = -1;
+        upper = length - 1;
+    } else {
+        lower = 0;
+        upper = length;
+    }
+
+    if (start_defined) {
+        *range_start = start < 0 ? max(lower, start + length) : min(upper, start);
+    } else {
+        *range_start = step_is_negative ? upper : lower;
+    }
+
+    if (stop_defined) {
+        *range_stop = stop < 0 ? max(lower, stop + length) : min(upper, stop);
+    } else {
+        *range_stop = step_is_negative ? lower : upper;
+    }
+}
+}  // namespace slice
+
+/**
+ * @brief A Python-like slice with **unresolved** indices.
+ */
+template<typename T>
+struct Slice {
+    bool start_defined;
+    T start;
+
+    bool stop_defined;
+    T stop;
+
+    bool step_defined;
+    T step;
+
+    Slice() { this->reset(); }
+
+    void reset() {
+        this->start_defined = false;
+        this->stop_defined = false;
+        this->step_defined = false;
+    }
+
+    void set_start(T start) {
+        this->start_defined = true;
+        this->start = start;
+    }
+
+    void set_stop(T stop) {
+        this->stop_defined = true;
+        this->stop = stop;
+    }
+
+    void set_step(T step) {
+        this->step_defined = true;
+        this->step = step;
+    }
+
+    /**
+     * @brief Resolve this slice as a range.
+     *
+     * In Python, this would be `range(*slice(start, stop, step).indices(length))`.
+     */
+    template<typename SizeT>
+    Range<T> indices(T length) {
+        // Reference:
+        // https://github.com/python/cpython/blob/main/Objects/sliceobject.c#L388
+        debug_assert(SizeT, length >= 0);
+
+        Range<T> result;
+        slice::indices(start_defined, start, stop_defined, stop, step_defined, step, length, &result.start,
+                       &result.stop, &result.step);
+        return result;
+    }
+
+    /**
+     * @brief Like `.indices()` but with assertions.
+     */
+    template<typename SizeT>
+    Range<T> indices_checked(T length) {
+        // TODO: Switch to `SizeT length`
+
+        if (length < 0) {
+            raise_exception(SizeT, EXN_VALUE_ERROR, "length should not be negative, got {0}", length, NO_PARAM,
+                            NO_PARAM);
+        }
+
+        if (this->step_defined && this->step == 0) {
+            raise_exception(SizeT, EXN_VALUE_ERROR, "slice step cannot be zero", NO_PARAM, NO_PARAM, NO_PARAM);
+        }
+
+        return this->indices<SizeT>(length);
+    }
+};
+}  // namespace
+
+extern "C" {
+SliceIndex __nac3_slice_index_bound(SliceIndex i, const SliceIndex len) {
+    if (i < 0) {
+        i = len + i;
+    }
+    if (i < 0) {
+        return 0;
+    } else if (i > len) {
+        return len;
+    }
+    return i;
+}
+}

nac3core/nac3core_derive/Cargo.toml

@@ -0,0 +1,21 @@
+[package]
+name = "nac3core_derive"
+version = "0.1.0"
+edition = "2021"
+
+[lib]
+proc-macro = true
+
+[[test]]
+name = "structfields_tests"
+path = "tests/structfields_test.rs"
+
+[dev-dependencies]
+nac3core = { path = ".." }
+trybuild = { version = "1.0", features = ["diff"] }
+
+[dependencies]
+proc-macro2 = "1.0"
+proc-macro-error = "1.0"
+syn = "2.0"
+quote = "1.0"

nac3core/nac3core_derive/src/lib.rs

@@ -0,0 +1,320 @@
+use proc_macro::TokenStream;
+use proc_macro_error::{abort, proc_macro_error};
+use quote::quote;
+use syn::{
+    parse_macro_input, spanned::Spanned, Data, DataStruct, Expr, ExprField, ExprMethodCall,
+    ExprPath, GenericArgument, Ident, LitStr, Path, PathArguments, Type, TypePath,
+};
+
+/// Extracts all generic arguments of a [`Type`] into a [`Vec`].
+///
+/// Returns [`Some`] of a possibly-empty [`Vec`] if the path of `ty` matches with
+/// `expected_ty_name`, otherwise returns [`None`].
+fn extract_generic_args(expected_ty_name: &'static str, ty: &Type) -> Option<Vec<GenericArgument>> {
+    let Type::Path(TypePath { qself: None, path, .. }) = ty else {
+        return None;
+    };
+
+    let segments = &path.segments;
+    if segments.len() != 1 {
+        return None;
+    };
+
+    let segment = segments.iter().next().unwrap();
+    if segment.ident != expected_ty_name {
+        return None;
+    }
+
+    let PathArguments::AngleBracketed(path_args) = &segment.arguments else {
+        return Some(Vec::new());
+    };
+    let args = &path_args.args;
+
+    Some(args.iter().cloned().collect::<Vec<_>>())
+}
+
+/// Maps a `path` matching one of the `target_idents` into the `replacement` [`Ident`].
+fn map_path_to_ident(path: &Path, target_idents: &[&str], replacement: &str) -> Option<Ident> {
+    path.require_ident()
+        .ok()
+        .filter(|ident| target_idents.iter().any(|target| ident == target))
+        .map(|ident| Ident::new(replacement, ident.span()))
+}
+
+/// Extracts the left-hand side of a dot-expression.
+fn extract_dot_operand(expr: &Expr) -> Option<&Expr> {
+    match expr {
+        Expr::MethodCall(ExprMethodCall { receiver: operand, .. })
+        | Expr::Field(ExprField { base: operand, .. }) => Some(operand),
+        _ => None,
+    }
+}
+
+/// Replaces the top-level receiver of a dot-expression with an [`Ident`], returning `Some(&mut expr)` if the
+/// replacement is performed.
+///
+/// The top-level receiver is the left-most receiver expression, e.g. the top-level receiver of `a.b.c.foo()` is `a`.
+fn replace_top_level_receiver(expr: &mut Expr, ident: Ident) -> Option<&mut Expr> {
+    if let Expr::MethodCall(ExprMethodCall { receiver: operand, .. })
+    | Expr::Field(ExprField { base: operand, .. }) = expr
+    {
+        return if extract_dot_operand(operand).is_some() {
+            if replace_top_level_receiver(operand, ident).is_some() {
+                Some(expr)
+            } else {
+                None
+            }
+        } else {
+            *operand = Box::new(Expr::Path(ExprPath {
+                attrs: Vec::default(),
+                qself: None,
+                path: ident.into(),
+            }));
+
+            Some(expr)
+        };
+    }
+
+    None
+}
+
+/// Iterates all operands to the left-hand side of the `.` of an [expression][`Expr`], i.e. the container operand of all
+/// [`Expr::Field`] and the receiver operand of all [`Expr::MethodCall`].
+///
+/// The iterator will return the operand expressions in reverse order of appearance. For example, `a.b.c.func()` will
+/// return `vec![c, b, a]`.
+fn iter_dot_operands(expr: &Expr) -> impl Iterator<Item = &Expr> {
+    let mut o = extract_dot_operand(expr);
+
+    std::iter::from_fn(move || {
+        let this = o;
+        o = o.as_ref().and_then(|o| extract_dot_operand(o));
+
+        this
+    })
+}
+
+/// Normalizes a value expression for use when creating an instance of this structure, returning a
+/// [`proc_macro2::TokenStream`] of tokens representing the normalized expression.
+fn normalize_value_expr(expr: &Expr) -> proc_macro2::TokenStream {
+    match &expr {
+        Expr::Path(ExprPath { qself: None, path, .. }) => {
+            if let Some(ident) = map_path_to_ident(path, &["usize", "size_t"], "llvm_usize") {
+                quote! { #ident }
+            } else {
+                abort!(
+                    path,
+                    format!(
+                        "Expected one of `size_t`, `usize`, or an implicit call expression in #[value_type(...)], found {}", 
+                        quote!(#expr).to_string(),
+                    )
+                )
+            }
+        }
+
+        Expr::Call(_) => {
+            quote! { ctx.#expr }
+        }
+
+        Expr::MethodCall(_) => {
+            let base_receiver = iter_dot_operands(expr).last();
+
+            match base_receiver {
+                // `usize.{...}`, `size_t.{...}` -> Rewrite the identifiers to `llvm_usize`
+                Some(Expr::Path(ExprPath { qself: None, path, .. }))
+                    if map_path_to_ident(path, &["usize", "size_t"], "llvm_usize").is_some() =>
+                {
+                    let ident =
+                        map_path_to_ident(path, &["usize", "size_t"], "llvm_usize").unwrap();
+
+                    let mut expr = expr.clone();
+                    let expr = replace_top_level_receiver(&mut expr, ident).unwrap();
+
+                    quote!(#expr)
+                }
+
+                // `ctx.{...}`, `context.{...}` -> Rewrite the identifiers to `ctx`
+                Some(Expr::Path(ExprPath { qself: None, path, .. }))
+                    if map_path_to_ident(path, &["ctx", "context"], "ctx").is_some() =>
+                {
+                    let ident = map_path_to_ident(path, &["ctx", "context"], "ctx").unwrap();
+
+                    let mut expr = expr.clone();
+                    let expr = replace_top_level_receiver(&mut expr, ident).unwrap();
+
+                    quote!(#expr)
+                }
+
+                // No reserved identifier prefix -> Prepend `ctx.` to the entire expression
+                _ => quote! { ctx.#expr },
+            }
+        }
+
+        _ => {
+            abort!(
+                expr,
+                format!(
+                    "Expected one of `size_t`, `usize`, or an implicit call expression in #[value_type(...)], found {}", 
+                    quote!(#expr).to_string(),
+                )
+            )
+        }
+    }
+}
+
+/// Derives an implementation of `codegen::types::structure::StructFields`.
+///
+/// The benefit of using `#[derive(StructFields)]` is that all index- or order-dependent logic required by
+/// `impl StructFields` is automatically generated by this implementation, including the field index as required by
+/// `StructField::new` and the fields as returned by `StructFields::to_vec`.
+///
+/// # Prerequisites
+///
+/// In order to derive from [`StructFields`], you must implement (or derive) [`Eq`] and [`Copy`] as required by
+/// `StructFields`.
+///
+/// Moreover, `#[derive(StructFields)]` can only be used for `struct`s with named fields, and may only contain fields
+/// with either `StructField` or [`PhantomData`] types.
+///
+/// # Attributes for [`StructFields`]
+///
+/// Each `StructField` field must be declared with the `#[value_type(...)]` attribute. The argument of `value_type`
+/// accepts one of the following:
+///
+/// - An expression returning an instance of `inkwell::types::BasicType` (with or without the receiver `ctx`/`context`).
+/// For example, `context.i8_type()`, `ctx.i8_type()`, and `i8_type()` all refer to `i8`.
+/// - The reserved identifiers `usize` and `size_t` referring to an `inkwell::types::IntType` of the platform-dependent
+/// integer size. `usize` and `size_t` can also be used as the receiver to other method calls, e.g.
+/// `usize.array_type(3)`.
+///
+/// # Example
+///
+/// The following is an example of an LLVM slice implemented using `#[derive(StructFields)]`.
+///
+/// ```rust,ignore
+/// use nac3core::{
+///     codegen::types::structure::StructField,
+///     inkwell::{
+///         values::{IntValue, PointerValue},
+///         AddressSpace,
+///     },
+/// };
+/// use nac3core_derive::StructFields;
+///
+/// // All classes that implement StructFields must also implement Eq and Copy
+/// #[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+/// pub struct SliceValue<'ctx> {
+///     // Declares ptr have a value type of i8*
+///     //
+///     // Can also be written as `ctx.i8_type().ptr_type(...)` or `context.i8_type().ptr_type(...)`
+///     #[value_type(i8_type().ptr_type(AddressSpace::default()))]
+///     ptr: StructField<'ctx, PointerValue<'ctx>>,
+///
+///     // Declares len have a value type of usize, depending on the target compilation platform
+///     #[value_type(usize)]
+///     len: StructField<'ctx, IntValue<'ctx>>,
+/// }
+/// ```
+#[proc_macro_derive(StructFields, attributes(value_type))]
+#[proc_macro_error]
+pub fn derive(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as syn::DeriveInput);
+    let ident = &input.ident;
+
+    let Data::Struct(DataStruct { fields, .. }) = &input.data else {
+        abort!(input, "Only structs with named fields are supported");
+    };
+    if let Err(err_span) =
+        fields
+            .iter()
+            .try_for_each(|field| if field.ident.is_some() { Ok(()) } else { Err(field.span()) })
+    {
+        abort!(err_span, "Only structs with named fields are supported");
+    };
+
+    // Check if struct<'ctx>
+    if input.generics.params.len() != 1 {
+        abort!(input.generics, "Expected exactly 1 generic parameter")
+    }
+
+    let phantom_info = fields
+        .iter()
+        .filter(|field| extract_generic_args("PhantomData", &field.ty).is_some())
+        .map(|field| field.ident.as_ref().unwrap())
+        .cloned()
+        .collect::<Vec<_>>();
+
+    let field_info = fields
+        .iter()
+        .filter(|field| extract_generic_args("PhantomData", &field.ty).is_none())
+        .map(|field| {
+            let ident = field.ident.as_ref().unwrap();
+            let ty = &field.ty;
+
+            let Some(_) = extract_generic_args("StructField", ty) else {
+                abort!(field, "Only StructField and PhantomData are allowed")
+            };
+
+            let attrs = &field.attrs;
+            let Some(value_type_attr) =
+                attrs.iter().find(|attr| attr.path().is_ident("value_type"))
+            else {
+                abort!(field, "Expected #[value_type(...)] attribute for field");
+            };
+
+            let Ok(value_type_expr) = value_type_attr.parse_args::<Expr>() else {
+                abort!(value_type_attr, "Expected expression in #[value_type(...)]");
+            };
+
+            let value_expr_toks = normalize_value_expr(&value_type_expr);
+
+            (ident.clone(), value_expr_toks)
+        })
+        .collect::<Vec<_>>();
+
+    // `<*>::new` impl of `StructField` and `PhantomData` for `StructFields::new`
+    let phantoms_create = phantom_info
+        .iter()
+        .map(|id| quote! { #id: ::std::marker::PhantomData })
+        .collect::<Vec<_>>();
+    let fields_create = field_info
+        .iter()
+        .map(|(id, ty)| {
+            let id_lit = LitStr::new(&id.to_string(), id.span());
+            quote! {
+                #id: ::nac3core::codegen::types::structure::StructField::create(
+                    &mut counter,
+                    #id_lit,
+                    #ty,
+                )
+            }
+        })
+        .collect::<Vec<_>>();
+
+    // `.into()` impl of `StructField` for `StructFields::to_vec`
+    let fields_into =
+        field_info.iter().map(|(id, _)| quote! { self.#id.into() }).collect::<Vec<_>>();
+
+    let impl_block = quote! {
+        impl<'ctx> ::nac3core::codegen::types::structure::StructFields<'ctx> for #ident<'ctx> {
+            fn new(ctx: impl ::nac3core::inkwell::context::AsContextRef<'ctx>, llvm_usize: ::nac3core::inkwell::types::IntType<'ctx>) -> Self {
+                let ctx = unsafe { ::nac3core::inkwell::context::ContextRef::new(ctx.as_ctx_ref()) };
+
+                let mut counter = ::nac3core::codegen::types::structure::FieldIndexCounter::default();
+
+                #ident {
+                    #(#fields_create),*
+                    #(#phantoms_create),*
+                }
+            }
+
+            fn to_vec(&self) -> ::std::vec::Vec<(&'static str, ::nac3core::inkwell::types::BasicTypeEnum<'ctx>)> {
+                vec![
+                    #(#fields_into),*
+                ]
+            }
+        }
+    };
+
+    impl_block.into()
+}

nac3core/nac3core_derive/tests/structfields_empty.rs

@@ -0,0 +1,9 @@
+use nac3core_derive::StructFields;
+use std::marker::PhantomData;
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct EmptyValue<'ctx> {
+    _phantom: PhantomData<&'ctx ()>,
+}
+
+fn main() {}

nac3core/nac3core_derive/tests/structfields_ndarray.rs

@@ -0,0 +1,20 @@
+use nac3core::{
+    codegen::types::structure::StructField,
+    inkwell::{
+        values::{IntValue, PointerValue},
+        AddressSpace,
+    },
+};
+use nac3core_derive::StructFields;
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct NDArrayValue<'ctx> {
+    #[value_type(usize)]
+    ndims: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(usize.ptr_type(AddressSpace::default()))]
+    shape: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(i8_type().ptr_type(AddressSpace::default()))]
+    data: StructField<'ctx, PointerValue<'ctx>>,
+}
+
+fn main() {}

nac3core/nac3core_derive/tests/structfields_slice.rs

@@ -0,0 +1,18 @@
+use nac3core::{
+    codegen::types::structure::StructField,
+    inkwell::{
+        values::{IntValue, PointerValue},
+        AddressSpace,
+    },
+};
+use nac3core_derive::StructFields;
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct SliceValue<'ctx> {
+    #[value_type(i8_type().ptr_type(AddressSpace::default()))]
+    ptr: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(usize)]
+    len: StructField<'ctx, IntValue<'ctx>>,
+}
+
+fn main() {}

nac3core/nac3core_derive/tests/structfields_slice_context.rs

@@ -0,0 +1,18 @@
+use nac3core::{
+    codegen::types::structure::StructField,
+    inkwell::{
+        values::{IntValue, PointerValue},
+        AddressSpace,
+    },
+};
+use nac3core_derive::StructFields;
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct SliceValue<'ctx> {
+    #[value_type(context.i8_type().ptr_type(AddressSpace::default()))]
+    ptr: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(usize)]
+    len: StructField<'ctx, IntValue<'ctx>>,
+}
+
+fn main() {}

nac3core/nac3core_derive/tests/structfields_slice_ctx.rs

@@ -0,0 +1,18 @@
+use nac3core::{
+    codegen::types::structure::StructField,
+    inkwell::{
+        values::{IntValue, PointerValue},
+        AddressSpace,
+    },
+};
+use nac3core_derive::StructFields;
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct SliceValue<'ctx> {
+    #[value_type(ctx.i8_type().ptr_type(AddressSpace::default()))]
+    ptr: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(usize)]
+    len: StructField<'ctx, IntValue<'ctx>>,
+}
+
+fn main() {}

nac3core/nac3core_derive/tests/structfields_slice_sizet.rs

@@ -0,0 +1,18 @@
+use nac3core::{
+    codegen::types::structure::StructField,
+    inkwell::{
+        values::{IntValue, PointerValue},
+        AddressSpace,
+    },
+};
+use nac3core_derive::StructFields;
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct SliceValue<'ctx> {
+    #[value_type(i8_type().ptr_type(AddressSpace::default()))]
+    ptr: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(size_t)]
+    len: StructField<'ctx, IntValue<'ctx>>,
+}
+
+fn main() {}

nac3core/nac3core_derive/tests/structfields_test.rs

@@ -0,0 +1,10 @@
+#[test]
+fn test_parse_empty() {
+    let t = trybuild::TestCases::new();
+    t.pass("tests/structfields_empty.rs");
+    t.pass("tests/structfields_slice.rs");
+    t.pass("tests/structfields_slice_ctx.rs");
+    t.pass("tests/structfields_slice_context.rs");
+    t.pass("tests/structfields_slice_sizet.rs");
+    t.pass("tests/structfields_ndarray.rs");
+}

nac3core/src/codegen/concrete_type.rs

@@ -1,3 +1,9 @@
+use std::collections::HashMap;
+
+use indexmap::IndexMap;
+
+use nac3parser::ast::StrRef;
+
 use crate::{
     symbol_resolver::SymbolValue,
     toplevel::DefinitionId,
@@ -9,10 +15,6 @@ use crate::{
     },
 };
 
-use indexmap::IndexMap;
-use nac3parser::ast::StrRef;
-use std::collections::HashMap;
-
 pub struct ConcreteTypeStore {
     store: Vec<ConcreteTypeEnum>,
 }

nac3core/src/codegen/extern_fns.rs

@@ -1,8 +1,10 @@
-use inkwell::attributes::{Attribute, AttributeLoc};
+use inkwell::{
-use inkwell::values::{BasicValueEnum, CallSiteValue, FloatValue, IntValue};
+    attributes::{Attribute, AttributeLoc},
+    values::{BasicValueEnum, CallSiteValue, FloatValue, IntValue},
+};
 use itertools::Either;
 
-use crate::codegen::CodeGenContext;
+use super::CodeGenContext;
 
 /// Macro to generate extern function
 /// Both function return type and function parameter type are `FloatValue`

nac3core/src/codegen/generator.rs

@@ -1,16 +1,18 @@
-use crate::{
-    codegen::{bool_to_i1, bool_to_i8, classes::ArraySliceValue, expr::*, stmt::*, CodeGenContext},
-    symbol_resolver::ValueEnum,
-    toplevel::{DefinitionId, TopLevelDef},
-    typecheck::typedef::{FunSignature, Type},
-};
 use inkwell::{
     context::Context,
     types::{BasicTypeEnum, IntType},
     values::{BasicValueEnum, IntValue, PointerValue},
 };
+
 use nac3parser::ast::{Expr, Stmt, StrRef};
 
+use super::{bool_to_i1, bool_to_i8, expr::*, stmt::*, values::ArraySliceValue, CodeGenContext};
+use crate::{
+    symbol_resolver::ValueEnum,
+    toplevel::{DefinitionId, TopLevelDef},
+    typecheck::typedef::{FunSignature, Type},
+};
+
 pub trait CodeGenerator {
     /// Return the module name for the code generator.
     fn get_name(&self) -> &str;

nac3core/src/codegen/irrt/irrt.cpp

@@ -1,414 +0,0 @@
-using int8_t = _BitInt(8);
-using uint8_t = unsigned _BitInt(8);
-using int32_t = _BitInt(32);
-using uint32_t = unsigned _BitInt(32);
-using int64_t = _BitInt(64);
-using uint64_t = unsigned _BitInt(64);
-
-// NDArray indices are always `uint32_t`.
-using NDIndex = uint32_t;
-// The type of an index or a value describing the length of a range/slice is always `int32_t`.
-using SliceIndex = int32_t;
-
-namespace {
-template <typename T>
-const T& max(const T& a, const T& b) {
-    return a > b ? a : b;
-}
-
-template <typename T>
-const T& min(const T& a, const T& b) {
-    return a > b ? b : a;
-}
-
-// adapted from GNU Scientific Library: https://git.savannah.gnu.org/cgit/gsl.git/tree/sys/pow_int.c
-// need to make sure `exp >= 0` before calling this function
-template <typename T>
-T __nac3_int_exp_impl(T base, T exp) {
-    T res = 1;
-    /* repeated squaring method */
-    do {
-        if (exp & 1) {
-            res *= base; /* for n odd */
-        }
-        exp >>= 1;
-        base *= base;
-    } while (exp);
-    return res;
-}
-
-template <typename SizeT>
-SizeT __nac3_ndarray_calc_size_impl(
-    const SizeT* list_data,
-    SizeT list_len,
-    SizeT begin_idx,
-    SizeT end_idx
-) {
-    __builtin_assume(end_idx <= list_len);
-
-    SizeT num_elems = 1;
-    for (SizeT i = begin_idx; i < end_idx; ++i) {
-        SizeT val = list_data[i];
-        __builtin_assume(val > 0);
-        num_elems *= val;
-    }
-    return num_elems;
-}
-
-template <typename SizeT>
-void __nac3_ndarray_calc_nd_indices_impl(
-    SizeT index,
-    const SizeT* dims,
-    SizeT num_dims,
-    NDIndex* idxs
-) {
-    SizeT stride = 1;
-    for (SizeT dim = 0; dim < num_dims; dim++) {
-        SizeT i = num_dims - dim - 1;
-        __builtin_assume(dims[i] > 0);
-        idxs[i] = (index / stride) % dims[i];
-        stride *= dims[i];
-    }
-}
-
-template <typename SizeT>
-SizeT __nac3_ndarray_flatten_index_impl(
-    const SizeT* dims,
-    SizeT num_dims,
-    const NDIndex* indices,
-    SizeT num_indices
-) {
-    SizeT idx = 0;
-    SizeT stride = 1;
-    for (SizeT i = 0; i < num_dims; ++i) {
-        SizeT ri = num_dims - i - 1;
-        if (ri < num_indices) {
-            idx += stride * indices[ri];
-        }
-
-        __builtin_assume(dims[i] > 0);
-        stride *= dims[ri];
-    }
-    return idx;
-}
-
-template <typename SizeT>
-void __nac3_ndarray_calc_broadcast_impl(
-    const SizeT* lhs_dims,
-    SizeT lhs_ndims,
-    const SizeT* rhs_dims,
-    SizeT rhs_ndims,
-    SizeT* out_dims
-) {
-    SizeT max_ndims = lhs_ndims > rhs_ndims ? lhs_ndims : rhs_ndims;
-
-    for (SizeT i = 0; i < max_ndims; ++i) {
-        const SizeT* lhs_dim_sz = i < lhs_ndims ? &lhs_dims[lhs_ndims - i - 1] : nullptr;
-        const SizeT* rhs_dim_sz = i < rhs_ndims ? &rhs_dims[rhs_ndims - i - 1] : nullptr;
-        SizeT* out_dim = &out_dims[max_ndims - i - 1];
-
-        if (lhs_dim_sz == nullptr) {
-            *out_dim = *rhs_dim_sz;
-        } else if (rhs_dim_sz == nullptr) {
-            *out_dim = *lhs_dim_sz;
-        } else if (*lhs_dim_sz == 1) {
-            *out_dim = *rhs_dim_sz;
-        } else if (*rhs_dim_sz == 1) {
-            *out_dim = *lhs_dim_sz;
-        } else if (*lhs_dim_sz == *rhs_dim_sz) {
-            *out_dim = *lhs_dim_sz;
-        } else {
-            __builtin_unreachable();
-        }
-    }
-}
-
-template <typename SizeT>
-void __nac3_ndarray_calc_broadcast_idx_impl(
-    const SizeT* src_dims,
-    SizeT src_ndims,
-    const NDIndex* in_idx,
-    NDIndex* out_idx
-) {
-    for (SizeT i = 0; i < src_ndims; ++i) {
-        SizeT src_i = src_ndims - i - 1;
-        out_idx[src_i] = src_dims[src_i] == 1 ? 0 : in_idx[src_i];
-    }
-}
-}  // namespace
-
-extern "C" {
-#define DEF_nac3_int_exp_(T) \
-    T __nac3_int_exp_##T(T base, T exp) {\
-        return __nac3_int_exp_impl(base, exp);\
-    }
-
-DEF_nac3_int_exp_(int32_t)
-DEF_nac3_int_exp_(int64_t)
-DEF_nac3_int_exp_(uint32_t)
-DEF_nac3_int_exp_(uint64_t)
-
-SliceIndex __nac3_slice_index_bound(SliceIndex i, const SliceIndex len) {
-    if (i < 0) {
-        i = len + i;
-    }
-    if (i < 0) {
-        return 0;
-    } else if (i > len) {
-        return len;
-    }
-    return i;
-}
-
-SliceIndex __nac3_range_slice_len(
-    const SliceIndex start,
-    const SliceIndex end,
-    const SliceIndex step
-) {
-    SliceIndex diff = end - start;
-    if (diff > 0 && step > 0) {
-        return ((diff - 1) / step) + 1;
-    } else if (diff < 0 && step < 0) {
-        return ((diff + 1) / step) + 1;
-    } else {
-        return 0;
-    }
-}
-
-// Handle list assignment and dropping part of the list when
-// both dest_step and src_step are +1.
-// - All the index must *not* be out-of-bound or negative,
-// - The end index is *inclusive*,
-// - The length of src and dest slice size should already
-// be checked: if dest.step == 1 then len(src) <= len(dest) else len(src) == len(dest)
-SliceIndex __nac3_list_slice_assign_var_size(
-    SliceIndex dest_start,
-    SliceIndex dest_end,
-    SliceIndex dest_step,
-    uint8_t* dest_arr,
-    SliceIndex dest_arr_len,
-    SliceIndex src_start,
-    SliceIndex src_end,
-    SliceIndex src_step,
-    uint8_t* src_arr,
-    SliceIndex src_arr_len,
-    const SliceIndex size
-) {
-    /* if dest_arr_len == 0, do nothing since we do not support extending list */
-    if (dest_arr_len == 0) return dest_arr_len;
-    /* if both step is 1, memmove directly, handle the dropping of the list, and shrink size */
-    if (src_step == dest_step && dest_step == 1) {
-        const SliceIndex src_len = (src_end >= src_start) ? (src_end - src_start + 1) : 0;
-        const SliceIndex dest_len = (dest_end >= dest_start) ? (dest_end - dest_start + 1) : 0;
-        if (src_len > 0) {
-            __builtin_memmove(
-                dest_arr + dest_start * size,
-                src_arr + src_start * size,
-                src_len * size
-            );
-        }
-        if (dest_len > 0) {
-            /* dropping */
-            __builtin_memmove(
-                dest_arr + (dest_start + src_len) * size,
-                dest_arr + (dest_end + 1) * size,
-                (dest_arr_len - dest_end - 1) * size
-            );
-        }
-        /* shrink size */
-        return dest_arr_len - (dest_len - src_len);
-    }
-    /* if two range overlaps, need alloca */
-    uint8_t need_alloca =
-        (dest_arr == src_arr)
-        && !(
-            max(dest_start, dest_end) < min(src_start, src_end)
-            || max(src_start, src_end) < min(dest_start, dest_end)
-        );
-    if (need_alloca) {
-        uint8_t* tmp = reinterpret_cast<uint8_t *>(__builtin_alloca(src_arr_len * size));
-        __builtin_memcpy(tmp, src_arr, src_arr_len * size);
-        src_arr = tmp;
-    }
-    SliceIndex src_ind = src_start;
-    SliceIndex dest_ind = dest_start;
-    for (;
-        (src_step > 0) ? (src_ind <= src_end) : (src_ind >= src_end);
-        src_ind += src_step, dest_ind += dest_step
-    ) {
-        /* for constant optimization */
-        if (size == 1) {
-            __builtin_memcpy(dest_arr + dest_ind, src_arr + src_ind, 1);
-        } else if (size == 4) {
-            __builtin_memcpy(dest_arr + dest_ind * 4, src_arr + src_ind * 4, 4);
-        } else if (size == 8) {
-            __builtin_memcpy(dest_arr + dest_ind * 8, src_arr + src_ind * 8, 8);
-        } else {
-            /* memcpy for var size, cannot overlap after previous alloca */
-            __builtin_memcpy(dest_arr + dest_ind * size, src_arr + src_ind * size, size);
-        }
-    }
-    /* only dest_step == 1 can we shrink the dest list. */
-    /* size should be ensured prior to calling this function */
-    if (dest_step == 1 && dest_end >= dest_start) {
-        __builtin_memmove(
-            dest_arr + dest_ind * size,
-            dest_arr + (dest_end + 1) * size,
-            (dest_arr_len - dest_end - 1) * size
-        );
-        return dest_arr_len - (dest_end - dest_ind) - 1;
-    }
-    return dest_arr_len;
-}
-
-int32_t __nac3_isinf(double x) {
-    return __builtin_isinf(x);
-}
-
-int32_t __nac3_isnan(double x) {
-    return __builtin_isnan(x);
-}
-
-double tgamma(double arg);
-
-double __nac3_gamma(double z) {
-    // Handling for denormals
-    //     | x                 | Python gamma(x) | C tgamma(x) |
-    // --- | ----------------- | --------------- | ----------- |
-    // (1) | nan               | nan             | nan         |
-    // (2) | -inf              | -inf            | inf         |
-    // (3) | inf               | inf             | inf         |
-    // (4) | 0.0               | inf             | inf         |
-    // (5) | {-1.0, -2.0, ...} | inf             | nan         |
-
-    // (1)-(3)
-    if (__builtin_isinf(z) || __builtin_isnan(z)) {
-        return z;
-    }
-
-    double v = tgamma(z);
-
-    // (4)-(5)
-    return __builtin_isinf(v) || __builtin_isnan(v) ? __builtin_inf() : v;
-}
-
-double lgamma(double arg);
-
-double __nac3_gammaln(double x) {
-    // libm's handling of value overflows differs from scipy:
-    // - scipy: gammaln(-inf) -> -inf
-    // - libm : lgamma(-inf) -> inf
-
-    if (__builtin_isinf(x)) {
-        return x;
-    }
-
-    return lgamma(x);
-}
-
-double j0(double x);
-
-double __nac3_j0(double x) {
-    // libm's handling of value overflows differs from scipy:
-    // - scipy: j0(inf) -> nan
-    // - libm : j0(inf) -> 0.0
-
-    if (__builtin_isinf(x)) {
-        return __builtin_nan("");
-    }
-
-    return j0(x);
-}
-
-uint32_t __nac3_ndarray_calc_size(
-    const uint32_t* list_data,
-    uint32_t list_len,
-    uint32_t begin_idx,
-    uint32_t end_idx
-) {
-    return __nac3_ndarray_calc_size_impl(list_data, list_len, begin_idx, end_idx);
-}
-
-uint64_t __nac3_ndarray_calc_size64(
-    const uint64_t* list_data,
-    uint64_t list_len,
-    uint64_t begin_idx,
-    uint64_t end_idx
-) {
-    return __nac3_ndarray_calc_size_impl(list_data, list_len, begin_idx, end_idx);
-}
-
-void __nac3_ndarray_calc_nd_indices(
-    uint32_t index,
-    const uint32_t* dims,
-    uint32_t num_dims,
-    NDIndex* idxs
-) {
-    __nac3_ndarray_calc_nd_indices_impl(index, dims, num_dims, idxs);
-}
-
-void __nac3_ndarray_calc_nd_indices64(
-    uint64_t index,
-    const uint64_t* dims,
-    uint64_t num_dims,
-    NDIndex* idxs
-) {
-    __nac3_ndarray_calc_nd_indices_impl(index, dims, num_dims, idxs);
-}
-
-uint32_t __nac3_ndarray_flatten_index(
-    const uint32_t* dims,
-    uint32_t num_dims,
-    const NDIndex* indices,
-    uint32_t num_indices
-) {
-    return __nac3_ndarray_flatten_index_impl(dims, num_dims, indices, num_indices);
-}
-
-uint64_t __nac3_ndarray_flatten_index64(
-    const uint64_t* dims,
-    uint64_t num_dims,
-    const NDIndex* indices,
-    uint64_t num_indices
-) {
-    return __nac3_ndarray_flatten_index_impl(dims, num_dims, indices, num_indices);
-}
-
-void __nac3_ndarray_calc_broadcast(
-    const uint32_t* lhs_dims,
-    uint32_t lhs_ndims,
-    const uint32_t* rhs_dims,
-    uint32_t rhs_ndims,
-    uint32_t* out_dims
-) {
-    return __nac3_ndarray_calc_broadcast_impl(lhs_dims, lhs_ndims, rhs_dims, rhs_ndims, out_dims);
-}
-
-void __nac3_ndarray_calc_broadcast64(
-    const uint64_t* lhs_dims,
-    uint64_t lhs_ndims,
-    const uint64_t* rhs_dims,
-    uint64_t rhs_ndims,
-    uint64_t* out_dims
-) {
-    return __nac3_ndarray_calc_broadcast_impl(lhs_dims, lhs_ndims, rhs_dims, rhs_ndims, out_dims);
-}
-
-void __nac3_ndarray_calc_broadcast_idx(
-    const uint32_t* src_dims,
-    uint32_t src_ndims,
-    const NDIndex* in_idx,
-    NDIndex* out_idx
-) {
-    __nac3_ndarray_calc_broadcast_idx_impl(src_dims, src_ndims, in_idx, out_idx);
-}
-
-void __nac3_ndarray_calc_broadcast_idx64(
-    const uint64_t* src_dims,
-    uint64_t src_ndims,
-    const NDIndex* in_idx,
-    NDIndex* out_idx
-) {
-    __nac3_ndarray_calc_broadcast_idx_impl(src_dims, src_ndims, in_idx, out_idx);
-}
-}  // extern "C"

nac3core/src/codegen/irrt/list.rs

@@ -0,0 +1,162 @@
+use inkwell::{
+    types::BasicTypeEnum,
+    values::{BasicValueEnum, CallSiteValue, IntValue},
+    AddressSpace, IntPredicate,
+};
+use itertools::Either;
+
+use super::calculate_len_for_slice_range;
+use crate::codegen::{
+    macros::codegen_unreachable,
+    values::{ArrayLikeValue, ListValue},
+    CodeGenContext, CodeGenerator,
+};
+
+/// This function handles 'end' **inclusively**.
+/// Order of tuples `assign_idx` and `value_idx` is ('start', 'end', 'step').
+/// Negative index should be handled before entering this function
+pub fn list_slice_assignment<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    ty: BasicTypeEnum<'ctx>,
+    dest_arr: ListValue<'ctx>,
+    dest_idx: (IntValue<'ctx>, IntValue<'ctx>, IntValue<'ctx>),
+    src_arr: ListValue<'ctx>,
+    src_idx: (IntValue<'ctx>, IntValue<'ctx>, IntValue<'ctx>),
+) {
+    let size_ty = generator.get_size_type(ctx.ctx);
+    let int8_ptr = ctx.ctx.i8_type().ptr_type(AddressSpace::default());
+    let int32 = ctx.ctx.i32_type();
+    let (fun_symbol, elem_ptr_type) = ("__nac3_list_slice_assign_var_size", int8_ptr);
+    let slice_assign_fun = {
+        let ty_vec = vec![
+            int32.into(),         // dest start idx
+            int32.into(),         // dest end idx
+            int32.into(),         // dest step
+            elem_ptr_type.into(), // dest arr ptr
+            int32.into(),         // dest arr len
+            int32.into(),         // src start idx
+            int32.into(),         // src end idx
+            int32.into(),         // src step
+            elem_ptr_type.into(), // src arr ptr
+            int32.into(),         // src arr len
+            int32.into(),         // size
+        ];
+        ctx.module.get_function(fun_symbol).unwrap_or_else(|| {
+            let fn_t = int32.fn_type(ty_vec.as_slice(), false);
+            ctx.module.add_function(fun_symbol, fn_t, None)
+        })
+    };
+
+    let zero = int32.const_zero();
+    let one = int32.const_int(1, false);
+    let dest_arr_ptr = dest_arr.data().base_ptr(ctx, generator);
+    let dest_arr_ptr =
+        ctx.builder.build_pointer_cast(dest_arr_ptr, elem_ptr_type, "dest_arr_ptr_cast").unwrap();
+    let dest_len = dest_arr.load_size(ctx, Some("dest.len"));
+    let dest_len = ctx.builder.build_int_truncate_or_bit_cast(dest_len, int32, "srclen32").unwrap();
+    let src_arr_ptr = src_arr.data().base_ptr(ctx, generator);
+    let src_arr_ptr =
+        ctx.builder.build_pointer_cast(src_arr_ptr, elem_ptr_type, "src_arr_ptr_cast").unwrap();
+    let src_len = src_arr.load_size(ctx, Some("src.len"));
+    let src_len = ctx.builder.build_int_truncate_or_bit_cast(src_len, int32, "srclen32").unwrap();
+
+    // index in bound and positive should be done
+    // assert if dest.step == 1 then len(src) <= len(dest) else len(src) == len(dest), and
+    // throw exception if not satisfied
+    let src_end = ctx
+        .builder
+        .build_select(
+            ctx.builder.build_int_compare(IntPredicate::SLT, src_idx.2, zero, "is_neg").unwrap(),
+            ctx.builder.build_int_sub(src_idx.1, one, "e_min_one").unwrap(),
+            ctx.builder.build_int_add(src_idx.1, one, "e_add_one").unwrap(),
+            "final_e",
+        )
+        .map(BasicValueEnum::into_int_value)
+        .unwrap();
+    let dest_end = ctx
+        .builder
+        .build_select(
+            ctx.builder.build_int_compare(IntPredicate::SLT, dest_idx.2, zero, "is_neg").unwrap(),
+            ctx.builder.build_int_sub(dest_idx.1, one, "e_min_one").unwrap(),
+            ctx.builder.build_int_add(dest_idx.1, one, "e_add_one").unwrap(),
+            "final_e",
+        )
+        .map(BasicValueEnum::into_int_value)
+        .unwrap();
+    let src_slice_len =
+        calculate_len_for_slice_range(generator, ctx, src_idx.0, src_end, src_idx.2);
+    let dest_slice_len =
+        calculate_len_for_slice_range(generator, ctx, dest_idx.0, dest_end, dest_idx.2);
+    let src_eq_dest = ctx
+        .builder
+        .build_int_compare(IntPredicate::EQ, src_slice_len, dest_slice_len, "slice_src_eq_dest")
+        .unwrap();
+    let src_slt_dest = ctx
+        .builder
+        .build_int_compare(IntPredicate::SLT, src_slice_len, dest_slice_len, "slice_src_slt_dest")
+        .unwrap();
+    let dest_step_eq_one = ctx
+        .builder
+        .build_int_compare(
+            IntPredicate::EQ,
+            dest_idx.2,
+            dest_idx.2.get_type().const_int(1, false),
+            "slice_dest_step_eq_one",
+        )
+        .unwrap();
+    let cond_1 = ctx.builder.build_and(dest_step_eq_one, src_slt_dest, "slice_cond_1").unwrap();
+    let cond = ctx.builder.build_or(src_eq_dest, cond_1, "slice_cond").unwrap();
+    ctx.make_assert(
+        generator,
+        cond,
+        "0:ValueError",
+        "attempt to assign sequence of size {0} to slice of size {1} with step size {2}",
+        [Some(src_slice_len), Some(dest_slice_len), Some(dest_idx.2)],
+        ctx.current_loc,
+    );
+
+    let new_len = {
+        let args = vec![
+            dest_idx.0.into(),   // dest start idx
+            dest_idx.1.into(),   // dest end idx
+            dest_idx.2.into(),   // dest step
+            dest_arr_ptr.into(), // dest arr ptr
+            dest_len.into(),     // dest arr len
+            src_idx.0.into(),    // src start idx
+            src_idx.1.into(),    // src end idx
+            src_idx.2.into(),    // src step
+            src_arr_ptr.into(),  // src arr ptr
+            src_len.into(),      // src arr len
+            {
+                let s = match ty {
+                    BasicTypeEnum::FloatType(t) => t.size_of(),
+                    BasicTypeEnum::IntType(t) => t.size_of(),
+                    BasicTypeEnum::PointerType(t) => t.size_of(),
+                    BasicTypeEnum::StructType(t) => t.size_of().unwrap(),
+                    _ => codegen_unreachable!(ctx),
+                };
+                ctx.builder.build_int_truncate_or_bit_cast(s, int32, "size").unwrap()
+            }
+            .into(),
+        ];
+        ctx.builder
+            .build_call(slice_assign_fun, args.as_slice(), "slice_assign")
+            .map(CallSiteValue::try_as_basic_value)
+            .map(|v| v.map_left(BasicValueEnum::into_int_value))
+            .map(Either::unwrap_left)
+            .unwrap()
+    };
+    // update length
+    let need_update =
+        ctx.builder.build_int_compare(IntPredicate::NE, new_len, dest_len, "need_update").unwrap();
+    let current = ctx.builder.get_insert_block().unwrap().get_parent().unwrap();
+    let update_bb = ctx.ctx.append_basic_block(current, "update");
+    let cont_bb = ctx.ctx.append_basic_block(current, "cont");
+    ctx.builder.build_conditional_branch(need_update, update_bb, cont_bb).unwrap();
+    ctx.builder.position_at_end(update_bb);
+    let new_len = ctx.builder.build_int_z_extend_or_bit_cast(new_len, size_ty, "new_len").unwrap();
+    dest_arr.store_size(ctx, generator, new_len);
+    ctx.builder.build_unconditional_branch(cont_bb).unwrap();
+    ctx.builder.position_at_end(cont_bb);
+}

nac3core/src/codegen/irrt/math.rs

@@ -0,0 +1,152 @@
+use inkwell::{
+    values::{BasicValueEnum, CallSiteValue, FloatValue, IntValue},
+    IntPredicate,
+};
+use itertools::Either;
+
+use crate::codegen::{
+    macros::codegen_unreachable,
+    {CodeGenContext, CodeGenerator},
+};
+
+// repeated squaring method adapted from GNU Scientific Library:
+// https://git.savannah.gnu.org/cgit/gsl.git/tree/sys/pow_int.c
+pub fn integer_power<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    base: IntValue<'ctx>,
+    exp: IntValue<'ctx>,
+    signed: bool,
+) -> IntValue<'ctx> {
+    let symbol = match (base.get_type().get_bit_width(), exp.get_type().get_bit_width(), signed) {
+        (32, 32, true) => "__nac3_int_exp_int32_t",
+        (64, 64, true) => "__nac3_int_exp_int64_t",
+        (32, 32, false) => "__nac3_int_exp_uint32_t",
+        (64, 64, false) => "__nac3_int_exp_uint64_t",
+        _ => codegen_unreachable!(ctx),
+    };
+    let base_type = base.get_type();
+    let pow_fun = ctx.module.get_function(symbol).unwrap_or_else(|| {
+        let fn_type = base_type.fn_type(&[base_type.into(), base_type.into()], false);
+        ctx.module.add_function(symbol, fn_type, None)
+    });
+    // throw exception when exp < 0
+    let ge_zero = ctx
+        .builder
+        .build_int_compare(
+            IntPredicate::SGE,
+            exp,
+            exp.get_type().const_zero(),
+            "assert_int_pow_ge_0",
+        )
+        .unwrap();
+    ctx.make_assert(
+        generator,
+        ge_zero,
+        "0:ValueError",
+        "integer power must be positive or zero",
+        [None, None, None],
+        ctx.current_loc,
+    );
+    ctx.builder
+        .build_call(pow_fun, &[base.into(), exp.into()], "call_int_pow")
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_int_value))
+        .map(Either::unwrap_left)
+        .unwrap()
+}
+
+/// Generates a call to `isinf` in IR. Returns an `i1` representing the result.
+pub fn call_isinf<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    v: FloatValue<'ctx>,
+) -> IntValue<'ctx> {
+    let intrinsic_fn = ctx.module.get_function("__nac3_isinf").unwrap_or_else(|| {
+        let fn_type = ctx.ctx.i32_type().fn_type(&[ctx.ctx.f64_type().into()], false);
+        ctx.module.add_function("__nac3_isinf", fn_type, None)
+    });
+
+    let ret = ctx
+        .builder
+        .build_call(intrinsic_fn, &[v.into()], "isinf")
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_int_value))
+        .map(Either::unwrap_left)
+        .unwrap();
+
+    generator.bool_to_i1(ctx, ret)
+}
+
+/// Generates a call to `isnan` in IR. Returns an `i1` representing the result.
+pub fn call_isnan<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    v: FloatValue<'ctx>,
+) -> IntValue<'ctx> {
+    let intrinsic_fn = ctx.module.get_function("__nac3_isnan").unwrap_or_else(|| {
+        let fn_type = ctx.ctx.i32_type().fn_type(&[ctx.ctx.f64_type().into()], false);
+        ctx.module.add_function("__nac3_isnan", fn_type, None)
+    });
+
+    let ret = ctx
+        .builder
+        .build_call(intrinsic_fn, &[v.into()], "isnan")
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_int_value))
+        .map(Either::unwrap_left)
+        .unwrap();
+
+    generator.bool_to_i1(ctx, ret)
+}
+
+/// Generates a call to `gamma` in IR. Returns an `f64` representing the result.
+pub fn call_gamma<'ctx>(ctx: &CodeGenContext<'ctx, '_>, v: FloatValue<'ctx>) -> FloatValue<'ctx> {
+    let llvm_f64 = ctx.ctx.f64_type();
+
+    let intrinsic_fn = ctx.module.get_function("__nac3_gamma").unwrap_or_else(|| {
+        let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
+        ctx.module.add_function("__nac3_gamma", fn_type, None)
+    });
+
+    ctx.builder
+        .build_call(intrinsic_fn, &[v.into()], "gamma")
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_float_value))
+        .map(Either::unwrap_left)
+        .unwrap()
+}
+
+/// Generates a call to `gammaln` in IR. Returns an `f64` representing the result.
+pub fn call_gammaln<'ctx>(ctx: &CodeGenContext<'ctx, '_>, v: FloatValue<'ctx>) -> FloatValue<'ctx> {
+    let llvm_f64 = ctx.ctx.f64_type();
+
+    let intrinsic_fn = ctx.module.get_function("__nac3_gammaln").unwrap_or_else(|| {
+        let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
+        ctx.module.add_function("__nac3_gammaln", fn_type, None)
+    });
+
+    ctx.builder
+        .build_call(intrinsic_fn, &[v.into()], "gammaln")
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_float_value))
+        .map(Either::unwrap_left)
+        .unwrap()
+}
+
+/// Generates a call to `j0` in IR. Returns an `f64` representing the result.
+pub fn call_j0<'ctx>(ctx: &CodeGenContext<'ctx, '_>, v: FloatValue<'ctx>) -> FloatValue<'ctx> {
+    let llvm_f64 = ctx.ctx.f64_type();
+
+    let intrinsic_fn = ctx.module.get_function("__nac3_j0").unwrap_or_else(|| {
+        let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
+        ctx.module.add_function("__nac3_j0", fn_type, None)
+    });
+
+    ctx.builder
+        .build_call(intrinsic_fn, &[v.into()], "j0")
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_float_value))
+        .map(Either::unwrap_left)
+        .unwrap()
+}

nac3core/src/codegen/irrt/mod.rs

@@ -1,28 +1,29 @@
-use crate::typecheck::typedef::Type;
-
-use super::{
-    classes::{
-        ArrayLikeIndexer, ArrayLikeValue, ArraySliceValue, ListValue, NDArrayValue,
-        TypedArrayLikeAdapter, UntypedArrayLikeAccessor,
-    },
-    llvm_intrinsics, CodeGenContext, CodeGenerator,
-};
-use crate::codegen::classes::TypedArrayLikeAccessor;
-use crate::codegen::stmt::gen_for_callback_incrementing;
 use inkwell::{
     attributes::{Attribute, AttributeLoc},
     context::Context,
     memory_buffer::MemoryBuffer,
     module::Module,
-    types::{BasicTypeEnum, IntType},
+    values::{BasicValue, BasicValueEnum, IntValue},
-    values::{BasicValueEnum, CallSiteValue, FloatValue, IntValue},
+    IntPredicate,
-    AddressSpace, IntPredicate,
 };
-use itertools::Either;
+
 use nac3parser::ast::Expr;
 
+use super::{CodeGenContext, CodeGenerator};
+use crate::{symbol_resolver::SymbolResolver, typecheck::typedef::Type};
+pub use list::*;
+pub use math::*;
+pub use range::*;
+pub use slice::*;
+
+mod list;
+mod math;
+pub mod ndarray;
+mod range;
+mod slice;
+
 #[must_use]
-pub fn load_irrt(ctx: &Context) -> Module {
+pub fn load_irrt<'ctx>(ctx: &'ctx Context, symbol_resolver: &dyn SymbolResolver) -> Module<'ctx> {
     let bitcode_buf = MemoryBuffer::create_from_memory_range(
         include_bytes!(concat!(env!("OUT_DIR"), "/irrt.bc")),
         "irrt_bitcode_buffer",
@@ -38,89 +39,47 @@ pub fn load_irrt(ctx: &Context) -> Module {
         let function = irrt_mod.get_function(symbol).unwrap();
         function.add_attribute(AttributeLoc::Function, ctx.create_enum_attribute(inline_attr, 0));
     }
+
+    // Initialize all global `EXN_*` exception IDs in IRRT with the [`SymbolResolver`].
+    let exn_id_type = ctx.i32_type();
+    let errors = &[
+        ("EXN_INDEX_ERROR", "0:IndexError"),
+        ("EXN_VALUE_ERROR", "0:ValueError"),
+        ("EXN_ASSERTION_ERROR", "0:AssertionError"),
+        ("EXN_TYPE_ERROR", "0:TypeError"),
+    ];
+    for (irrt_name, symbol_name) in errors {
+        let exn_id = symbol_resolver.get_string_id(symbol_name);
+        let exn_id = exn_id_type.const_int(exn_id as u64, false).as_basic_value_enum();
+
+        let global = irrt_mod.get_global(irrt_name).unwrap_or_else(|| {
+            panic!("Exception symbol name '{irrt_name}' should exist in the IRRT LLVM module")
+        });
+        global.set_initializer(&exn_id);
+    }
+
     irrt_mod
 }
 
-// repeated squaring method adapted from GNU Scientific Library:
+/// Returns the name of a function which contains variants for 32-bit and 64-bit `size_t`.
-// https://git.savannah.gnu.org/cgit/gsl.git/tree/sys/pow_int.c
+///
-pub fn integer_power<'ctx, G: CodeGenerator + ?Sized>(
+/// - When [`TypeContext::size_type`] is 32-bits, the function name is `fn_name}`.
-    generator: &mut G,
+/// - When [`TypeContext::size_type`] is 64-bits, the function name is `{fn_name}64`.
-    ctx: &mut CodeGenContext<'ctx, '_>,
+#[must_use]
-    base: IntValue<'ctx>,
+pub fn get_usize_dependent_function_name<G: CodeGenerator + ?Sized>(
-    exp: IntValue<'ctx>,
+    generator: &G,
-    signed: bool,
+    ctx: &CodeGenContext<'_, '_>,
-) -> IntValue<'ctx> {
+    name: &str,
-    let symbol = match (base.get_type().get_bit_width(), exp.get_type().get_bit_width(), signed) {
+) -> String {
-        (32, 32, true) => "__nac3_int_exp_int32_t",
+    let mut name = name.to_owned();
-        (64, 64, true) => "__nac3_int_exp_int64_t",
+    match generator.get_size_type(ctx.ctx).get_bit_width() {
-        (32, 32, false) => "__nac3_int_exp_uint32_t",
+        32 => {}
-        (64, 64, false) => "__nac3_int_exp_uint64_t",
+        64 => name.push_str("64"),
-        _ => unreachable!(),
+        bit_width => {
-    };
+            panic!("Unsupported int type bit width {bit_width}, must be either 32-bits or 64-bits")
-    let base_type = base.get_type();
+        }
-    let pow_fun = ctx.module.get_function(symbol).unwrap_or_else(|| {
+    }
-        let fn_type = base_type.fn_type(&[base_type.into(), base_type.into()], false);
+    name
-        ctx.module.add_function(symbol, fn_type, None)
-    });
-    // throw exception when exp < 0
-    let ge_zero = ctx
-        .builder
-        .build_int_compare(
-            IntPredicate::SGE,
-            exp,
-            exp.get_type().const_zero(),
-            "assert_int_pow_ge_0",
-        )
-        .unwrap();
-    ctx.make_assert(
-        generator,
-        ge_zero,
-        "0:ValueError",
-        "integer power must be positive or zero",
-        [None, None, None],
-        ctx.current_loc,
-    );
-    ctx.builder
-        .build_call(pow_fun, &[base.into(), exp.into()], "call_int_pow")
-        .map(CallSiteValue::try_as_basic_value)
-        .map(|v| v.map_left(BasicValueEnum::into_int_value))
-        .map(Either::unwrap_left)
-        .unwrap()
-}
-
-pub fn calculate_len_for_slice_range<'ctx, G: CodeGenerator + ?Sized>(
-    generator: &mut G,
-    ctx: &mut CodeGenContext<'ctx, '_>,
-    start: IntValue<'ctx>,
-    end: IntValue<'ctx>,
-    step: IntValue<'ctx>,
-) -> IntValue<'ctx> {
-    const SYMBOL: &str = "__nac3_range_slice_len";
-    let len_func = ctx.module.get_function(SYMBOL).unwrap_or_else(|| {
-        let i32_t = ctx.ctx.i32_type();
-        let fn_t = i32_t.fn_type(&[i32_t.into(), i32_t.into(), i32_t.into()], false);
-        ctx.module.add_function(SYMBOL, fn_t, None)
-    });
-
-    // assert step != 0, throw exception if not
-    let not_zero = ctx
-        .builder
-        .build_int_compare(IntPredicate::NE, step, step.get_type().const_zero(), "range_step_ne")
-        .unwrap();
-    ctx.make_assert(
-        generator,
-        not_zero,
-        "0:ValueError",
-        "step must not be zero",
-        [None, None, None],
-        ctx.current_loc,
-    );
-    ctx.builder
-        .build_call(len_func, &[start.into(), end.into(), step.into()], "calc_len")
-        .map(CallSiteValue::try_as_basic_value)
-        .map(|v| v.map_left(BasicValueEnum::into_int_value))
-        .map(Either::unwrap_left)
-        .unwrap()
 }
 
 /// NOTE: the output value of the end index of this function should be compared ***inclusively***,
@@ -288,644 +247,3 @@ pub fn handle_slice_indices<'ctx, G: CodeGenerator>(
         }
     }))
 }
-
-/// this function allows index out of range, since python
-/// allows index out of range in slice (`a = [1,2,3]; a[1:10] == [2,3]`).
-pub fn handle_slice_index_bound<'ctx, G: CodeGenerator>(
-    i: &Expr<Option<Type>>,
-    ctx: &mut CodeGenContext<'ctx, '_>,
-    generator: &mut G,
-    length: IntValue<'ctx>,
-) -> Result<Option<IntValue<'ctx>>, String> {
-    const SYMBOL: &str = "__nac3_slice_index_bound";
-    let func = ctx.module.get_function(SYMBOL).unwrap_or_else(|| {
-        let i32_t = ctx.ctx.i32_type();
-        let fn_t = i32_t.fn_type(&[i32_t.into(), i32_t.into()], false);
-        ctx.module.add_function(SYMBOL, fn_t, None)
-    });
-
-    let i = if let Some(v) = generator.gen_expr(ctx, i)? {
-        v.to_basic_value_enum(ctx, generator, i.custom.unwrap())?
-    } else {
-        return Ok(None);
-    };
-    Ok(Some(
-        ctx.builder
-            .build_call(func, &[i.into(), length.into()], "bounded_ind")
-            .map(CallSiteValue::try_as_basic_value)
-            .map(|v| v.map_left(BasicValueEnum::into_int_value))
-            .map(Either::unwrap_left)
-            .unwrap(),
-    ))
-}
-
-/// This function handles 'end' **inclusively**.
-/// Order of tuples `assign_idx` and `value_idx` is ('start', 'end', 'step').
-/// Negative index should be handled before entering this function
-pub fn list_slice_assignment<'ctx, G: CodeGenerator + ?Sized>(
-    generator: &mut G,
-    ctx: &mut CodeGenContext<'ctx, '_>,
-    ty: BasicTypeEnum<'ctx>,
-    dest_arr: ListValue<'ctx>,
-    dest_idx: (IntValue<'ctx>, IntValue<'ctx>, IntValue<'ctx>),
-    src_arr: ListValue<'ctx>,
-    src_idx: (IntValue<'ctx>, IntValue<'ctx>, IntValue<'ctx>),
-) {
-    let size_ty = generator.get_size_type(ctx.ctx);
-    let int8_ptr = ctx.ctx.i8_type().ptr_type(AddressSpace::default());
-    let int32 = ctx.ctx.i32_type();
-    let (fun_symbol, elem_ptr_type) = ("__nac3_list_slice_assign_var_size", int8_ptr);
-    let slice_assign_fun = {
-        let ty_vec = vec![
-            int32.into(),         // dest start idx
-            int32.into(),         // dest end idx
-            int32.into(),         // dest step
-            elem_ptr_type.into(), // dest arr ptr
-            int32.into(),         // dest arr len
-            int32.into(),         // src start idx
-            int32.into(),         // src end idx
-            int32.into(),         // src step
-            elem_ptr_type.into(), // src arr ptr
-            int32.into(),         // src arr len
-            int32.into(),         // size
-        ];
-        ctx.module.get_function(fun_symbol).unwrap_or_else(|| {
-            let fn_t = int32.fn_type(ty_vec.as_slice(), false);
-            ctx.module.add_function(fun_symbol, fn_t, None)
-        })
-    };
-
-    let zero = int32.const_zero();
-    let one = int32.const_int(1, false);
-    let dest_arr_ptr = dest_arr.data().base_ptr(ctx, generator);
-    let dest_arr_ptr =
-        ctx.builder.build_pointer_cast(dest_arr_ptr, elem_ptr_type, "dest_arr_ptr_cast").unwrap();
-    let dest_len = dest_arr.load_size(ctx, Some("dest.len"));
-    let dest_len = ctx.builder.build_int_truncate_or_bit_cast(dest_len, int32, "srclen32").unwrap();
-    let src_arr_ptr = src_arr.data().base_ptr(ctx, generator);
-    let src_arr_ptr =
-        ctx.builder.build_pointer_cast(src_arr_ptr, elem_ptr_type, "src_arr_ptr_cast").unwrap();
-    let src_len = src_arr.load_size(ctx, Some("src.len"));
-    let src_len = ctx.builder.build_int_truncate_or_bit_cast(src_len, int32, "srclen32").unwrap();
-
-    // index in bound and positive should be done
-    // assert if dest.step == 1 then len(src) <= len(dest) else len(src) == len(dest), and
-    // throw exception if not satisfied
-    let src_end = ctx
-        .builder
-        .build_select(
-            ctx.builder.build_int_compare(IntPredicate::SLT, src_idx.2, zero, "is_neg").unwrap(),
-            ctx.builder.build_int_sub(src_idx.1, one, "e_min_one").unwrap(),
-            ctx.builder.build_int_add(src_idx.1, one, "e_add_one").unwrap(),
-            "final_e",
-        )
-        .map(BasicValueEnum::into_int_value)
-        .unwrap();
-    let dest_end = ctx
-        .builder
-        .build_select(
-            ctx.builder.build_int_compare(IntPredicate::SLT, dest_idx.2, zero, "is_neg").unwrap(),
-            ctx.builder.build_int_sub(dest_idx.1, one, "e_min_one").unwrap(),
-            ctx.builder.build_int_add(dest_idx.1, one, "e_add_one").unwrap(),
-            "final_e",
-        )
-        .map(BasicValueEnum::into_int_value)
-        .unwrap();
-    let src_slice_len =
-        calculate_len_for_slice_range(generator, ctx, src_idx.0, src_end, src_idx.2);
-    let dest_slice_len =
-        calculate_len_for_slice_range(generator, ctx, dest_idx.0, dest_end, dest_idx.2);
-    let src_eq_dest = ctx
-        .builder
-        .build_int_compare(IntPredicate::EQ, src_slice_len, dest_slice_len, "slice_src_eq_dest")
-        .unwrap();
-    let src_slt_dest = ctx
-        .builder
-        .build_int_compare(IntPredicate::SLT, src_slice_len, dest_slice_len, "slice_src_slt_dest")
-        .unwrap();
-    let dest_step_eq_one = ctx
-        .builder
-        .build_int_compare(
-            IntPredicate::EQ,
-            dest_idx.2,
-            dest_idx.2.get_type().const_int(1, false),
-            "slice_dest_step_eq_one",
-        )
-        .unwrap();
-    let cond_1 = ctx.builder.build_and(dest_step_eq_one, src_slt_dest, "slice_cond_1").unwrap();
-    let cond = ctx.builder.build_or(src_eq_dest, cond_1, "slice_cond").unwrap();
-    ctx.make_assert(
-        generator,
-        cond,
-        "0:ValueError",
-        "attempt to assign sequence of size {0} to slice of size {1} with step size {2}",
-        [Some(src_slice_len), Some(dest_slice_len), Some(dest_idx.2)],
-        ctx.current_loc,
-    );
-
-    let new_len = {
-        let args = vec![
-            dest_idx.0.into(),   // dest start idx
-            dest_idx.1.into(),   // dest end idx
-            dest_idx.2.into(),   // dest step
-            dest_arr_ptr.into(), // dest arr ptr
-            dest_len.into(),     // dest arr len
-            src_idx.0.into(),    // src start idx
-            src_idx.1.into(),    // src end idx
-            src_idx.2.into(),    // src step
-            src_arr_ptr.into(),  // src arr ptr
-            src_len.into(),      // src arr len
-            {
-                let s = match ty {
-                    BasicTypeEnum::FloatType(t) => t.size_of(),
-                    BasicTypeEnum::IntType(t) => t.size_of(),
-                    BasicTypeEnum::PointerType(t) => t.size_of(),
-                    BasicTypeEnum::StructType(t) => t.size_of().unwrap(),
-                    _ => unreachable!(),
-                };
-                ctx.builder.build_int_truncate_or_bit_cast(s, int32, "size").unwrap()
-            }
-            .into(),
-        ];
-        ctx.builder
-            .build_call(slice_assign_fun, args.as_slice(), "slice_assign")
-            .map(CallSiteValue::try_as_basic_value)
-            .map(|v| v.map_left(BasicValueEnum::into_int_value))
-            .map(Either::unwrap_left)
-            .unwrap()
-    };
-    // update length
-    let need_update =
-        ctx.builder.build_int_compare(IntPredicate::NE, new_len, dest_len, "need_update").unwrap();
-    let current = ctx.builder.get_insert_block().unwrap().get_parent().unwrap();
-    let update_bb = ctx.ctx.append_basic_block(current, "update");
-    let cont_bb = ctx.ctx.append_basic_block(current, "cont");
-    ctx.builder.build_conditional_branch(need_update, update_bb, cont_bb).unwrap();
-    ctx.builder.position_at_end(update_bb);
-    let new_len = ctx.builder.build_int_z_extend_or_bit_cast(new_len, size_ty, "new_len").unwrap();
-    dest_arr.store_size(ctx, generator, new_len);
-    ctx.builder.build_unconditional_branch(cont_bb).unwrap();
-    ctx.builder.position_at_end(cont_bb);
-}
-
-/// Generates a call to `isinf` in IR. Returns an `i1` representing the result.
-pub fn call_isinf<'ctx, G: CodeGenerator + ?Sized>(
-    generator: &mut G,
-    ctx: &CodeGenContext<'ctx, '_>,
-    v: FloatValue<'ctx>,
-) -> IntValue<'ctx> {
-    let intrinsic_fn = ctx.module.get_function("__nac3_isinf").unwrap_or_else(|| {
-        let fn_type = ctx.ctx.i32_type().fn_type(&[ctx.ctx.f64_type().into()], false);
-        ctx.module.add_function("__nac3_isinf", fn_type, None)
-    });
-
-    let ret = ctx
-        .builder
-        .build_call(intrinsic_fn, &[v.into()], "isinf")
-        .map(CallSiteValue::try_as_basic_value)
-        .map(|v| v.map_left(BasicValueEnum::into_int_value))
-        .map(Either::unwrap_left)
-        .unwrap();
-
-    generator.bool_to_i1(ctx, ret)
-}
-
-/// Generates a call to `isnan` in IR. Returns an `i1` representing the result.
-pub fn call_isnan<'ctx, G: CodeGenerator + ?Sized>(
-    generator: &mut G,
-    ctx: &CodeGenContext<'ctx, '_>,
-    v: FloatValue<'ctx>,
-) -> IntValue<'ctx> {
-    let intrinsic_fn = ctx.module.get_function("__nac3_isnan").unwrap_or_else(|| {
-        let fn_type = ctx.ctx.i32_type().fn_type(&[ctx.ctx.f64_type().into()], false);
-        ctx.module.add_function("__nac3_isnan", fn_type, None)
-    });
-
-    let ret = ctx
-        .builder
-        .build_call(intrinsic_fn, &[v.into()], "isnan")
-        .map(CallSiteValue::try_as_basic_value)
-        .map(|v| v.map_left(BasicValueEnum::into_int_value))
-        .map(Either::unwrap_left)
-        .unwrap();
-
-    generator.bool_to_i1(ctx, ret)
-}
-
-/// Generates a call to `gamma` in IR. Returns an `f64` representing the result.
-pub fn call_gamma<'ctx>(ctx: &CodeGenContext<'ctx, '_>, v: FloatValue<'ctx>) -> FloatValue<'ctx> {
-    let llvm_f64 = ctx.ctx.f64_type();
-
-    let intrinsic_fn = ctx.module.get_function("__nac3_gamma").unwrap_or_else(|| {
-        let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
-        ctx.module.add_function("__nac3_gamma", fn_type, None)
-    });
-
-    ctx.builder
-        .build_call(intrinsic_fn, &[v.into()], "gamma")
-        .map(CallSiteValue::try_as_basic_value)
-        .map(|v| v.map_left(BasicValueEnum::into_float_value))
-        .map(Either::unwrap_left)
-        .unwrap()
-}
-
-/// Generates a call to `gammaln` in IR. Returns an `f64` representing the result.
-pub fn call_gammaln<'ctx>(ctx: &CodeGenContext<'ctx, '_>, v: FloatValue<'ctx>) -> FloatValue<'ctx> {
-    let llvm_f64 = ctx.ctx.f64_type();
-
-    let intrinsic_fn = ctx.module.get_function("__nac3_gammaln").unwrap_or_else(|| {
-        let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
-        ctx.module.add_function("__nac3_gammaln", fn_type, None)
-    });
-
-    ctx.builder
-        .build_call(intrinsic_fn, &[v.into()], "gammaln")
-        .map(CallSiteValue::try_as_basic_value)
-        .map(|v| v.map_left(BasicValueEnum::into_float_value))
-        .map(Either::unwrap_left)
-        .unwrap()
-}
-
-/// Generates a call to `j0` in IR. Returns an `f64` representing the result.
-pub fn call_j0<'ctx>(ctx: &CodeGenContext<'ctx, '_>, v: FloatValue<'ctx>) -> FloatValue<'ctx> {
-    let llvm_f64 = ctx.ctx.f64_type();
-
-    let intrinsic_fn = ctx.module.get_function("__nac3_j0").unwrap_or_else(|| {
-        let fn_type = llvm_f64.fn_type(&[llvm_f64.into()], false);
-        ctx.module.add_function("__nac3_j0", fn_type, None)
-    });
-
-    ctx.builder
-        .build_call(intrinsic_fn, &[v.into()], "j0")
-        .map(CallSiteValue::try_as_basic_value)
-        .map(|v| v.map_left(BasicValueEnum::into_float_value))
-        .map(Either::unwrap_left)
-        .unwrap()
-}
-
-/// Generates a call to `__nac3_ndarray_calc_size`. Returns an [`IntValue`] representing the
-/// calculated total size.
-///
-/// * `dims` - An [`ArrayLikeIndexer`] containing the size of each dimension.
-/// * `range` - The dimension index to begin and end (exclusively) calculating the dimensions for,
-///   or [`None`] if starting from the first dimension and ending at the last dimension
-///   respectively.
-pub fn call_ndarray_calc_size<'ctx, G, Dims>(
-    generator: &G,
-    ctx: &CodeGenContext<'ctx, '_>,
-    dims: &Dims,
-    (begin, end): (Option<IntValue<'ctx>>, Option<IntValue<'ctx>>),
-) -> IntValue<'ctx>
-where
-    G: CodeGenerator + ?Sized,
-    Dims: ArrayLikeIndexer<'ctx>,
-{
-    let llvm_usize = generator.get_size_type(ctx.ctx);
-    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
-
-    let ndarray_calc_size_fn_name = match llvm_usize.get_bit_width() {
-        32 => "__nac3_ndarray_calc_size",
-        64 => "__nac3_ndarray_calc_size64",
-        bw => unreachable!("Unsupported size type bit width: {}", bw),
-    };
-    let ndarray_calc_size_fn_t = llvm_usize.fn_type(
-        &[llvm_pusize.into(), llvm_usize.into(), llvm_usize.into(), llvm_usize.into()],
-        false,
-    );
-    let ndarray_calc_size_fn =
-        ctx.module.get_function(ndarray_calc_size_fn_name).unwrap_or_else(|| {
-            ctx.module.add_function(ndarray_calc_size_fn_name, ndarray_calc_size_fn_t, None)
-        });
-
-    let begin = begin.unwrap_or_else(|| llvm_usize.const_zero());
-    let end = end.unwrap_or_else(|| dims.size(ctx, generator));
-    ctx.builder
-        .build_call(
-            ndarray_calc_size_fn,
-            &[
-                dims.base_ptr(ctx, generator).into(),
-                dims.size(ctx, generator).into(),
-                begin.into(),
-                end.into(),
-            ],
-            "",
-        )
-        .map(CallSiteValue::try_as_basic_value)
-        .map(|v| v.map_left(BasicValueEnum::into_int_value))
-        .map(Either::unwrap_left)
-        .unwrap()
-}
-
-/// Generates a call to `__nac3_ndarray_calc_nd_indices`. Returns a [`TypeArrayLikeAdpater`]
-/// containing `i32` indices of the flattened index.
-///
-/// * `index` - The index to compute the multidimensional index for.
-/// * `ndarray` - LLVM pointer to the `NDArray`. This value must be the LLVM representation of an
-///   `NDArray`.
-pub fn call_ndarray_calc_nd_indices<'ctx, G: CodeGenerator + ?Sized>(
-    generator: &G,
-    ctx: &mut CodeGenContext<'ctx, '_>,
-    index: IntValue<'ctx>,
-    ndarray: NDArrayValue<'ctx>,
-) -> TypedArrayLikeAdapter<'ctx, IntValue<'ctx>> {
-    let llvm_void = ctx.ctx.void_type();
-    let llvm_i32 = ctx.ctx.i32_type();
-    let llvm_usize = generator.get_size_type(ctx.ctx);
-    let llvm_pi32 = llvm_i32.ptr_type(AddressSpace::default());
-    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
-
-    let ndarray_calc_nd_indices_fn_name = match llvm_usize.get_bit_width() {
-        32 => "__nac3_ndarray_calc_nd_indices",
-        64 => "__nac3_ndarray_calc_nd_indices64",
-        bw => unreachable!("Unsupported size type bit width: {}", bw),
-    };
-    let ndarray_calc_nd_indices_fn =
-        ctx.module.get_function(ndarray_calc_nd_indices_fn_name).unwrap_or_else(|| {
-            let fn_type = llvm_void.fn_type(
-                &[llvm_usize.into(), llvm_pusize.into(), llvm_usize.into(), llvm_pi32.into()],
-                false,
-            );
-
-            ctx.module.add_function(ndarray_calc_nd_indices_fn_name, fn_type, None)
-        });
-
-    let ndarray_num_dims = ndarray.load_ndims(ctx);
-    let ndarray_dims = ndarray.dim_sizes();
-
-    let indices = ctx.builder.build_array_alloca(llvm_i32, ndarray_num_dims, "").unwrap();
-
-    ctx.builder
-        .build_call(
-            ndarray_calc_nd_indices_fn,
-            &[
-                index.into(),
-                ndarray_dims.base_ptr(ctx, generator).into(),
-                ndarray_num_dims.into(),
-                indices.into(),
-            ],
-            "",
-        )
-        .unwrap();
-
-    TypedArrayLikeAdapter::from(
-        ArraySliceValue::from_ptr_val(indices, ndarray_num_dims, None),
-        Box::new(|_, v| v.into_int_value()),
-        Box::new(|_, v| v.into()),
-    )
-}
-
-fn call_ndarray_flatten_index_impl<'ctx, G, Indices>(
-    generator: &G,
-    ctx: &CodeGenContext<'ctx, '_>,
-    ndarray: NDArrayValue<'ctx>,
-    indices: &Indices,
-) -> IntValue<'ctx>
-where
-    G: CodeGenerator + ?Sized,
-    Indices: ArrayLikeIndexer<'ctx>,
-{
-    let llvm_i32 = ctx.ctx.i32_type();
-    let llvm_usize = generator.get_size_type(ctx.ctx);
-
-    let llvm_pi32 = llvm_i32.ptr_type(AddressSpace::default());
-    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
-
-    debug_assert_eq!(
-        IntType::try_from(indices.element_type(ctx, generator))
-            .map(IntType::get_bit_width)
-            .unwrap_or_default(),
-        llvm_i32.get_bit_width(),
-        "Expected i32 value for argument `indices` to `call_ndarray_flatten_index_impl`"
-    );
-    debug_assert_eq!(
-        indices.size(ctx, generator).get_type().get_bit_width(),
-        llvm_usize.get_bit_width(),
-        "Expected usize integer value for argument `indices_size` to `call_ndarray_flatten_index_impl`"
-    );
-
-    let ndarray_flatten_index_fn_name = match llvm_usize.get_bit_width() {
-        32 => "__nac3_ndarray_flatten_index",
-        64 => "__nac3_ndarray_flatten_index64",
-        bw => unreachable!("Unsupported size type bit width: {}", bw),
-    };
-    let ndarray_flatten_index_fn =
-        ctx.module.get_function(ndarray_flatten_index_fn_name).unwrap_or_else(|| {
-            let fn_type = llvm_usize.fn_type(
-                &[llvm_pusize.into(), llvm_usize.into(), llvm_pi32.into(), llvm_usize.into()],
-                false,
-            );
-
-            ctx.module.add_function(ndarray_flatten_index_fn_name, fn_type, None)
-        });
-
-    let ndarray_num_dims = ndarray.load_ndims(ctx);
-    let ndarray_dims = ndarray.dim_sizes();
-
-    let index = ctx
-        .builder
-        .build_call(
-            ndarray_flatten_index_fn,
-            &[
-                ndarray_dims.base_ptr(ctx, generator).into(),
-                ndarray_num_dims.into(),
-                indices.base_ptr(ctx, generator).into(),
-                indices.size(ctx, generator).into(),
-            ],
-            "",
-        )
-        .map(CallSiteValue::try_as_basic_value)
-        .map(|v| v.map_left(BasicValueEnum::into_int_value))
-        .map(Either::unwrap_left)
-        .unwrap();
-
-    index
-}
-
-/// Generates a call to `__nac3_ndarray_flatten_index`. Returns the flattened index for the
-/// multidimensional index.
-///
-/// * `ndarray` - LLVM pointer to the `NDArray`. This value must be the LLVM representation of an
-///   `NDArray`.
-/// * `indices` - The multidimensional index to compute the flattened index for.
-pub fn call_ndarray_flatten_index<'ctx, G, Index>(
-    generator: &mut G,
-    ctx: &mut CodeGenContext<'ctx, '_>,
-    ndarray: NDArrayValue<'ctx>,
-    indices: &Index,
-) -> IntValue<'ctx>
-where
-    G: CodeGenerator + ?Sized,
-    Index: ArrayLikeIndexer<'ctx>,
-{
-    call_ndarray_flatten_index_impl(generator, ctx, ndarray, indices)
-}
-
-/// Generates a call to `__nac3_ndarray_calc_broadcast`. Returns a tuple containing the number of
-/// dimension and size of each dimension of the resultant `ndarray`.
-pub fn call_ndarray_calc_broadcast<'ctx, G: CodeGenerator + ?Sized>(
-    generator: &mut G,
-    ctx: &mut CodeGenContext<'ctx, '_>,
-    lhs: NDArrayValue<'ctx>,
-    rhs: NDArrayValue<'ctx>,
-) -> TypedArrayLikeAdapter<'ctx, IntValue<'ctx>> {
-    let llvm_usize = generator.get_size_type(ctx.ctx);
-    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
-
-    let ndarray_calc_broadcast_fn_name = match llvm_usize.get_bit_width() {
-        32 => "__nac3_ndarray_calc_broadcast",
-        64 => "__nac3_ndarray_calc_broadcast64",
-        bw => unreachable!("Unsupported size type bit width: {}", bw),
-    };
-    let ndarray_calc_broadcast_fn =
-        ctx.module.get_function(ndarray_calc_broadcast_fn_name).unwrap_or_else(|| {
-            let fn_type = llvm_usize.fn_type(
-                &[
-                    llvm_pusize.into(),
-                    llvm_usize.into(),
-                    llvm_pusize.into(),
-                    llvm_usize.into(),
-                    llvm_pusize.into(),
-                ],
-                false,
-            );
-
-            ctx.module.add_function(ndarray_calc_broadcast_fn_name, fn_type, None)
-        });
-
-    let lhs_ndims = lhs.load_ndims(ctx);
-    let rhs_ndims = rhs.load_ndims(ctx);
-    let min_ndims = llvm_intrinsics::call_int_umin(ctx, lhs_ndims, rhs_ndims, None);
-
-    gen_for_callback_incrementing(
-        generator,
-        ctx,
-        None,
-        llvm_usize.const_zero(),
-        (min_ndims, false),
-        |generator, ctx, _, idx| {
-            let idx = ctx.builder.build_int_sub(min_ndims, idx, "").unwrap();
-            let (lhs_dim_sz, rhs_dim_sz) = unsafe {
-                (
-                    lhs.dim_sizes().get_typed_unchecked(ctx, generator, &idx, None),
-                    rhs.dim_sizes().get_typed_unchecked(ctx, generator, &idx, None),
-                )
-            };
-
-            let llvm_usize_const_one = llvm_usize.const_int(1, false);
-            let lhs_eqz = ctx
-                .builder
-                .build_int_compare(IntPredicate::EQ, lhs_dim_sz, llvm_usize_const_one, "")
-                .unwrap();
-            let rhs_eqz = ctx
-                .builder
-                .build_int_compare(IntPredicate::EQ, rhs_dim_sz, llvm_usize_const_one, "")
-                .unwrap();
-            let lhs_or_rhs_eqz = ctx.builder.build_or(lhs_eqz, rhs_eqz, "").unwrap();
-
-            let lhs_eq_rhs = ctx
-                .builder
-                .build_int_compare(IntPredicate::EQ, lhs_dim_sz, rhs_dim_sz, "")
-                .unwrap();
-
-            let is_compatible = ctx.builder.build_or(lhs_or_rhs_eqz, lhs_eq_rhs, "").unwrap();
-
-            ctx.make_assert(
-                generator,
-                is_compatible,
-                "0:ValueError",
-                "operands could not be broadcast together",
-                [None, None, None],
-                ctx.current_loc,
-            );
-
-            Ok(())
-        },
-        llvm_usize.const_int(1, false),
-    )
-    .unwrap();
-
-    let max_ndims = llvm_intrinsics::call_int_umax(ctx, lhs_ndims, rhs_ndims, None);
-    let lhs_dims = lhs.dim_sizes().base_ptr(ctx, generator);
-    let lhs_ndims = lhs.load_ndims(ctx);
-    let rhs_dims = rhs.dim_sizes().base_ptr(ctx, generator);
-    let rhs_ndims = rhs.load_ndims(ctx);
-    let out_dims = ctx.builder.build_array_alloca(llvm_usize, max_ndims, "").unwrap();
-    let out_dims = ArraySliceValue::from_ptr_val(out_dims, max_ndims, None);
-
-    ctx.builder
-        .build_call(
-            ndarray_calc_broadcast_fn,
-            &[
-                lhs_dims.into(),
-                lhs_ndims.into(),
-                rhs_dims.into(),
-                rhs_ndims.into(),
-                out_dims.base_ptr(ctx, generator).into(),
-            ],
-            "",
-        )
-        .unwrap();
-
-    TypedArrayLikeAdapter::from(
-        out_dims,
-        Box::new(|_, v| v.into_int_value()),
-        Box::new(|_, v| v.into()),
-    )
-}
-
-/// Generates a call to `__nac3_ndarray_calc_broadcast_idx`. Returns an [`ArrayAllocaValue`]
-/// containing the indices used for accessing `array` corresponding to the index of the broadcasted
-/// array `broadcast_idx`.
-pub fn call_ndarray_calc_broadcast_index<
-    'ctx,
-    G: CodeGenerator + ?Sized,
-    BroadcastIdx: UntypedArrayLikeAccessor<'ctx>,
->(
-    generator: &mut G,
-    ctx: &mut CodeGenContext<'ctx, '_>,
-    array: NDArrayValue<'ctx>,
-    broadcast_idx: &BroadcastIdx,
-) -> TypedArrayLikeAdapter<'ctx, IntValue<'ctx>> {
-    let llvm_i32 = ctx.ctx.i32_type();
-    let llvm_usize = generator.get_size_type(ctx.ctx);
-    let llvm_pi32 = llvm_i32.ptr_type(AddressSpace::default());
-    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
-
-    let ndarray_calc_broadcast_fn_name = match llvm_usize.get_bit_width() {
-        32 => "__nac3_ndarray_calc_broadcast_idx",
-        64 => "__nac3_ndarray_calc_broadcast_idx64",
-        bw => unreachable!("Unsupported size type bit width: {}", bw),
-    };
-    let ndarray_calc_broadcast_fn =
-        ctx.module.get_function(ndarray_calc_broadcast_fn_name).unwrap_or_else(|| {
-            let fn_type = llvm_usize.fn_type(
-                &[llvm_pusize.into(), llvm_usize.into(), llvm_pi32.into(), llvm_pi32.into()],
-                false,
-            );
-
-            ctx.module.add_function(ndarray_calc_broadcast_fn_name, fn_type, None)
-        });
-
-    let broadcast_size = broadcast_idx.size(ctx, generator);
-    let out_idx = ctx.builder.build_array_alloca(llvm_i32, broadcast_size, "").unwrap();
-
-    let array_dims = array.dim_sizes().base_ptr(ctx, generator);
-    let array_ndims = array.load_ndims(ctx);
-    let broadcast_idx_ptr = unsafe {
-        broadcast_idx.ptr_offset_unchecked(ctx, generator, &llvm_usize.const_zero(), None)
-    };
-
-    ctx.builder
-        .build_call(
-            ndarray_calc_broadcast_fn,
-            &[array_dims.into(), array_ndims.into(), broadcast_idx_ptr.into(), out_idx.into()],
-            "",
-        )
-        .unwrap();
-
-    TypedArrayLikeAdapter::from(
-        ArraySliceValue::from_ptr_val(out_idx, broadcast_size, None),
-        Box::new(|_, v| v.into_int_value()),
-        Box::new(|_, v| v.into()),
-    )
-}

nac3core/src/codegen/irrt/ndarray/basic.rs

@@ -0,0 +1,250 @@
+use inkwell::{
+    values::{BasicValueEnum, IntValue, PointerValue},
+    AddressSpace,
+};
+
+use crate::codegen::{
+    expr::{create_and_call_function, infer_and_call_function},
+    irrt::get_usize_dependent_function_name,
+    types::ProxyType,
+    values::{ndarray::NDArrayValue, ProxyValue},
+    CodeGenContext, CodeGenerator,
+};
+
+pub fn call_nac3_ndarray_util_assert_shape_no_negative<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndims: IntValue<'ctx>,
+    shape: PointerValue<'ctx>,
+) {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let name = get_usize_dependent_function_name(
+        generator,
+        ctx,
+        "__nac3_ndarray_util_assert_shape_no_negative",
+    );
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[(llvm_usize.into(), ndims.into()), (llvm_pusize.into(), shape.into())],
+        None,
+        None,
+    );
+}
+
+pub fn call_nac3_ndarray_util_assert_output_shape_same<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray_ndims: IntValue<'ctx>,
+    ndarray_shape: PointerValue<'ctx>,
+    output_ndims: IntValue<'ctx>,
+    output_shape: IntValue<'ctx>,
+) {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let name = get_usize_dependent_function_name(
+        generator,
+        ctx,
+        "__nac3_ndarray_util_assert_output_shape_same",
+    );
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[
+            (llvm_usize.into(), ndarray_ndims.into()),
+            (llvm_pusize.into(), ndarray_shape.into()),
+            (llvm_usize.into(), output_ndims.into()),
+            (llvm_pusize.into(), output_shape.into()),
+        ],
+        None,
+        None,
+    );
+}
+
+pub fn call_nac3_ndarray_size<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) -> IntValue<'ctx> {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = ndarray.get_type().as_base_type();
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_size");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        Some("size"),
+        None,
+    )
+    .map(BasicValueEnum::into_int_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_nbytes<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) -> IntValue<'ctx> {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = ndarray.get_type().as_base_type();
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_nbytes");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        Some("nbytes"),
+        None,
+    )
+    .map(BasicValueEnum::into_int_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_len<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) -> IntValue<'ctx> {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = ndarray.get_type().as_base_type();
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_len");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_usize.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        Some("len"),
+        None,
+    )
+    .map(BasicValueEnum::into_int_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_is_c_contiguous<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) -> IntValue<'ctx> {
+    let llvm_i1 = ctx.ctx.bool_type();
+    let llvm_ndarray = ndarray.get_type().as_base_type();
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_is_c_contiguous");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_i1.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        Some("is_c_contiguous"),
+        None,
+    )
+    .map(BasicValueEnum::into_int_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_get_nth_pelement<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+    index: IntValue<'ctx>,
+) -> PointerValue<'ctx> {
+    let llvm_i8 = ctx.ctx.i8_type();
+    let llvm_pi8 = llvm_i8.ptr_type(AddressSpace::default());
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_ndarray = ndarray.get_type().as_base_type();
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_get_nth_pelement");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_pi8.into()),
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into()), (llvm_usize.into(), index.into())],
+        Some("pelement"),
+        None,
+    )
+    .map(BasicValueEnum::into_pointer_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_get_pelement_by_indices<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+    indices: PointerValue<'ctx>,
+) -> PointerValue<'ctx> {
+    let llvm_i8 = ctx.ctx.i8_type();
+    let llvm_pi8 = llvm_i8.ptr_type(AddressSpace::default());
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+    let llvm_ndarray = ndarray.get_type().as_base_type();
+
+    let name =
+        get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_get_pelement_by_indices");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        Some(llvm_pi8.into()),
+        &[
+            (llvm_ndarray.into(), ndarray.as_base_value().into()),
+            (llvm_pusize.into(), indices.into()),
+        ],
+        Some("pelement"),
+        None,
+    )
+    .map(BasicValueEnum::into_pointer_value)
+    .unwrap()
+}
+
+pub fn call_nac3_ndarray_set_strides_by_shape<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+) {
+    let llvm_ndarray = ndarray.get_type().as_base_type();
+
+    let name =
+        get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_set_strides_by_shape");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        None,
+        &[(llvm_ndarray.into(), ndarray.as_base_value().into())],
+        None,
+        None,
+    );
+}
+
+pub fn call_nac3_ndarray_copy_data<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    src_ndarray: NDArrayValue<'ctx>,
+    dst_ndarray: NDArrayValue<'ctx>,
+) {
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_copy_data");
+
+    infer_and_call_function(
+        ctx,
+        &name,
+        None,
+        &[src_ndarray.as_base_value().into(), dst_ndarray.as_base_value().into()],
+        None,
+        None,
+    );
+}

nac3core/src/codegen/irrt/ndarray/indexing.rs

@@ -0,0 +1,29 @@
+use crate::codegen::{
+    expr::infer_and_call_function,
+    irrt::get_usize_dependent_function_name,
+    values::{ndarray::NDArrayValue, ArrayLikeValue, ArraySliceValue, ProxyValue},
+    CodeGenContext, CodeGenerator,
+};
+
+pub fn call_nac3_ndarray_index<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    indices: ArraySliceValue<'ctx>,
+    src_ndarray: NDArrayValue<'ctx>,
+    dst_ndarray: NDArrayValue<'ctx>,
+) {
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_ndarray_index");
+    infer_and_call_function(
+        ctx,
+        &name,
+        None,
+        &[
+            indices.size(ctx, generator).into(),
+            indices.base_ptr(ctx, generator).into(),
+            src_ndarray.as_base_value().into(),
+            dst_ndarray.as_base_value().into(),
+        ],
+        None,
+        None,
+    );
+}

nac3core/src/codegen/irrt/ndarray/iter.rs

@@ -0,0 +1,70 @@
+use inkwell::{
+    values::{BasicValueEnum, IntValue},
+    AddressSpace,
+};
+
+use crate::codegen::{
+    expr::{create_and_call_function, infer_and_call_function},
+    irrt::get_usize_dependent_function_name,
+    types::ProxyType,
+    values::{
+        ndarray::{NDArrayValue, NDIterValue},
+        ArrayLikeValue, ArraySliceValue, ProxyValue,
+    },
+    CodeGenContext, CodeGenerator,
+};
+
+pub fn call_nac3_nditer_initialize<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    iter: NDIterValue<'ctx>,
+    ndarray: NDArrayValue<'ctx>,
+    indices: ArraySliceValue<'ctx>,
+) {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_nditer_initialize");
+
+    create_and_call_function(
+        ctx,
+        &name,
+        None,
+        &[
+            (iter.get_type().as_base_type().into(), iter.as_base_value().into()),
+            (ndarray.get_type().as_base_type().into(), ndarray.as_base_value().into()),
+            (llvm_pusize.into(), indices.base_ptr(ctx, generator).into()),
+        ],
+        None,
+        None,
+    );
+}
+
+pub fn call_nac3_nditer_has_element<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    iter: NDIterValue<'ctx>,
+) -> IntValue<'ctx> {
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_nditer_has_element");
+
+    infer_and_call_function(
+        ctx,
+        &name,
+        Some(ctx.ctx.bool_type().into()),
+        &[iter.as_base_value().into()],
+        None,
+        None,
+    )
+    .map(BasicValueEnum::into_int_value)
+    .unwrap()
+}
+
+pub fn call_nac3_nditer_next<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    iter: NDIterValue<'ctx>,
+) {
+    let name = get_usize_dependent_function_name(generator, ctx, "__nac3_nditer_next");
+
+    infer_and_call_function(ctx, &name, None, &[iter.as_base_value().into()], None, None);
+}

nac3core/src/codegen/irrt/ndarray/mod.rs

@@ -0,0 +1,391 @@
+use inkwell::{
+    types::IntType,
+    values::{BasicValueEnum, CallSiteValue, IntValue},
+    AddressSpace, IntPredicate,
+};
+use itertools::Either;
+
+use crate::codegen::{
+    llvm_intrinsics,
+    macros::codegen_unreachable,
+    stmt::gen_for_callback_incrementing,
+    values::{
+        ndarray::NDArrayValue, ArrayLikeIndexer, ArrayLikeValue, ArraySliceValue,
+        TypedArrayLikeAccessor, TypedArrayLikeAdapter, UntypedArrayLikeAccessor,
+    },
+    CodeGenContext, CodeGenerator,
+};
+pub use basic::*;
+pub use indexing::*;
+pub use iter::*;
+
+mod basic;
+mod indexing;
+mod iter;
+
+/// Generates a call to `__nac3_ndarray_calc_size`. Returns an [`IntValue`] representing the
+/// calculated total size.
+///
+/// * `dims` - An [`ArrayLikeIndexer`] containing the size of each dimension.
+/// * `range` - The dimension index to begin and end (exclusively) calculating the dimensions for,
+///   or [`None`] if starting from the first dimension and ending at the last dimension
+///   respectively.
+pub fn call_ndarray_calc_size<'ctx, G, Dims>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    dims: &Dims,
+    (begin, end): (Option<IntValue<'ctx>>, Option<IntValue<'ctx>>),
+) -> IntValue<'ctx>
+where
+    G: CodeGenerator + ?Sized,
+    Dims: ArrayLikeIndexer<'ctx>,
+{
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let ndarray_calc_size_fn_name = match llvm_usize.get_bit_width() {
+        32 => "__nac3_ndarray_calc_size",
+        64 => "__nac3_ndarray_calc_size64",
+        bw => codegen_unreachable!(ctx, "Unsupported size type bit width: {}", bw),
+    };
+    let ndarray_calc_size_fn_t = llvm_usize.fn_type(
+        &[llvm_pusize.into(), llvm_usize.into(), llvm_usize.into(), llvm_usize.into()],
+        false,
+    );
+    let ndarray_calc_size_fn =
+        ctx.module.get_function(ndarray_calc_size_fn_name).unwrap_or_else(|| {
+            ctx.module.add_function(ndarray_calc_size_fn_name, ndarray_calc_size_fn_t, None)
+        });
+
+    let begin = begin.unwrap_or_else(|| llvm_usize.const_zero());
+    let end = end.unwrap_or_else(|| dims.size(ctx, generator));
+    ctx.builder
+        .build_call(
+            ndarray_calc_size_fn,
+            &[
+                dims.base_ptr(ctx, generator).into(),
+                dims.size(ctx, generator).into(),
+                begin.into(),
+                end.into(),
+            ],
+            "",
+        )
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_int_value))
+        .map(Either::unwrap_left)
+        .unwrap()
+}
+
+/// Generates a call to `__nac3_ndarray_calc_nd_indices`. Returns a [`TypeArrayLikeAdpater`]
+/// containing `i32` indices of the flattened index.
+///
+/// * `index` - The index to compute the multidimensional index for.
+/// * `ndarray` - LLVM pointer to the `NDArray`. This value must be the LLVM representation of an
+///   `NDArray`.
+pub fn call_ndarray_calc_nd_indices<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    index: IntValue<'ctx>,
+    ndarray: NDArrayValue<'ctx>,
+) -> TypedArrayLikeAdapter<'ctx, IntValue<'ctx>> {
+    let llvm_void = ctx.ctx.void_type();
+    let llvm_i32 = ctx.ctx.i32_type();
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pi32 = llvm_i32.ptr_type(AddressSpace::default());
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let ndarray_calc_nd_indices_fn_name = match llvm_usize.get_bit_width() {
+        32 => "__nac3_ndarray_calc_nd_indices",
+        64 => "__nac3_ndarray_calc_nd_indices64",
+        bw => codegen_unreachable!(ctx, "Unsupported size type bit width: {}", bw),
+    };
+    let ndarray_calc_nd_indices_fn =
+        ctx.module.get_function(ndarray_calc_nd_indices_fn_name).unwrap_or_else(|| {
+            let fn_type = llvm_void.fn_type(
+                &[llvm_usize.into(), llvm_pusize.into(), llvm_usize.into(), llvm_pi32.into()],
+                false,
+            );
+
+            ctx.module.add_function(ndarray_calc_nd_indices_fn_name, fn_type, None)
+        });
+
+    let ndarray_num_dims = ndarray.load_ndims(ctx);
+    let ndarray_dims = ndarray.shape();
+
+    let indices = ctx.builder.build_array_alloca(llvm_i32, ndarray_num_dims, "").unwrap();
+
+    ctx.builder
+        .build_call(
+            ndarray_calc_nd_indices_fn,
+            &[
+                index.into(),
+                ndarray_dims.base_ptr(ctx, generator).into(),
+                ndarray_num_dims.into(),
+                indices.into(),
+            ],
+            "",
+        )
+        .unwrap();
+
+    TypedArrayLikeAdapter::from(
+        ArraySliceValue::from_ptr_val(indices, ndarray_num_dims, None),
+        Box::new(|_, v| v.into_int_value()),
+        Box::new(|_, v| v.into()),
+    )
+}
+
+fn call_ndarray_flatten_index_impl<'ctx, G, Indices>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+    indices: &Indices,
+) -> IntValue<'ctx>
+where
+    G: CodeGenerator + ?Sized,
+    Indices: ArrayLikeIndexer<'ctx>,
+{
+    let llvm_i32 = ctx.ctx.i32_type();
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+
+    let llvm_pi32 = llvm_i32.ptr_type(AddressSpace::default());
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    debug_assert_eq!(
+        IntType::try_from(indices.element_type(ctx, generator))
+            .map(IntType::get_bit_width)
+            .unwrap_or_default(),
+        llvm_i32.get_bit_width(),
+        "Expected i32 value for argument `indices` to `call_ndarray_flatten_index_impl`"
+    );
+    debug_assert_eq!(
+        indices.size(ctx, generator).get_type().get_bit_width(),
+        llvm_usize.get_bit_width(),
+        "Expected usize integer value for argument `indices_size` to `call_ndarray_flatten_index_impl`"
+    );
+
+    let ndarray_flatten_index_fn_name = match llvm_usize.get_bit_width() {
+        32 => "__nac3_ndarray_flatten_index",
+        64 => "__nac3_ndarray_flatten_index64",
+        bw => codegen_unreachable!(ctx, "Unsupported size type bit width: {}", bw),
+    };
+    let ndarray_flatten_index_fn =
+        ctx.module.get_function(ndarray_flatten_index_fn_name).unwrap_or_else(|| {
+            let fn_type = llvm_usize.fn_type(
+                &[llvm_pusize.into(), llvm_usize.into(), llvm_pi32.into(), llvm_usize.into()],
+                false,
+            );
+
+            ctx.module.add_function(ndarray_flatten_index_fn_name, fn_type, None)
+        });
+
+    let ndarray_num_dims = ndarray.load_ndims(ctx);
+    let ndarray_dims = ndarray.shape();
+
+    let index = ctx
+        .builder
+        .build_call(
+            ndarray_flatten_index_fn,
+            &[
+                ndarray_dims.base_ptr(ctx, generator).into(),
+                ndarray_num_dims.into(),
+                indices.base_ptr(ctx, generator).into(),
+                indices.size(ctx, generator).into(),
+            ],
+            "",
+        )
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_int_value))
+        .map(Either::unwrap_left)
+        .unwrap();
+
+    index
+}
+
+/// Generates a call to `__nac3_ndarray_flatten_index`. Returns the flattened index for the
+/// multidimensional index.
+///
+/// * `ndarray` - LLVM pointer to the `NDArray`. This value must be the LLVM representation of an
+///   `NDArray`.
+/// * `indices` - The multidimensional index to compute the flattened index for.
+pub fn call_ndarray_flatten_index<'ctx, G, Index>(
+    generator: &G,
+    ctx: &CodeGenContext<'ctx, '_>,
+    ndarray: NDArrayValue<'ctx>,
+    indices: &Index,
+) -> IntValue<'ctx>
+where
+    G: CodeGenerator + ?Sized,
+    Index: ArrayLikeIndexer<'ctx>,
+{
+    call_ndarray_flatten_index_impl(generator, ctx, ndarray, indices)
+}
+
+/// Generates a call to `__nac3_ndarray_calc_broadcast`. Returns a tuple containing the number of
+/// dimension and size of each dimension of the resultant `ndarray`.
+pub fn call_ndarray_calc_broadcast<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    lhs: NDArrayValue<'ctx>,
+    rhs: NDArrayValue<'ctx>,
+) -> TypedArrayLikeAdapter<'ctx, IntValue<'ctx>> {
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let ndarray_calc_broadcast_fn_name = match llvm_usize.get_bit_width() {
+        32 => "__nac3_ndarray_calc_broadcast",
+        64 => "__nac3_ndarray_calc_broadcast64",
+        bw => codegen_unreachable!(ctx, "Unsupported size type bit width: {}", bw),
+    };
+    let ndarray_calc_broadcast_fn =
+        ctx.module.get_function(ndarray_calc_broadcast_fn_name).unwrap_or_else(|| {
+            let fn_type = llvm_usize.fn_type(
+                &[
+                    llvm_pusize.into(),
+                    llvm_usize.into(),
+                    llvm_pusize.into(),
+                    llvm_usize.into(),
+                    llvm_pusize.into(),
+                ],
+                false,
+            );
+
+            ctx.module.add_function(ndarray_calc_broadcast_fn_name, fn_type, None)
+        });
+
+    let lhs_ndims = lhs.load_ndims(ctx);
+    let rhs_ndims = rhs.load_ndims(ctx);
+    let min_ndims = llvm_intrinsics::call_int_umin(ctx, lhs_ndims, rhs_ndims, None);
+
+    gen_for_callback_incrementing(
+        generator,
+        ctx,
+        None,
+        llvm_usize.const_zero(),
+        (min_ndims, false),
+        |generator, ctx, _, idx| {
+            let idx = ctx.builder.build_int_sub(min_ndims, idx, "").unwrap();
+            let (lhs_dim_sz, rhs_dim_sz) = unsafe {
+                (
+                    lhs.shape().get_typed_unchecked(ctx, generator, &idx, None),
+                    rhs.shape().get_typed_unchecked(ctx, generator, &idx, None),
+                )
+            };
+
+            let llvm_usize_const_one = llvm_usize.const_int(1, false);
+            let lhs_eqz = ctx
+                .builder
+                .build_int_compare(IntPredicate::EQ, lhs_dim_sz, llvm_usize_const_one, "")
+                .unwrap();
+            let rhs_eqz = ctx
+                .builder
+                .build_int_compare(IntPredicate::EQ, rhs_dim_sz, llvm_usize_const_one, "")
+                .unwrap();
+            let lhs_or_rhs_eqz = ctx.builder.build_or(lhs_eqz, rhs_eqz, "").unwrap();
+
+            let lhs_eq_rhs = ctx
+                .builder
+                .build_int_compare(IntPredicate::EQ, lhs_dim_sz, rhs_dim_sz, "")
+                .unwrap();
+
+            let is_compatible = ctx.builder.build_or(lhs_or_rhs_eqz, lhs_eq_rhs, "").unwrap();
+
+            ctx.make_assert(
+                generator,
+                is_compatible,
+                "0:ValueError",
+                "operands could not be broadcast together",
+                [None, None, None],
+                ctx.current_loc,
+            );
+
+            Ok(())
+        },
+        llvm_usize.const_int(1, false),
+    )
+    .unwrap();
+
+    let max_ndims = llvm_intrinsics::call_int_umax(ctx, lhs_ndims, rhs_ndims, None);
+    let lhs_dims = lhs.shape().base_ptr(ctx, generator);
+    let lhs_ndims = lhs.load_ndims(ctx);
+    let rhs_dims = rhs.shape().base_ptr(ctx, generator);
+    let rhs_ndims = rhs.load_ndims(ctx);
+    let out_dims = ctx.builder.build_array_alloca(llvm_usize, max_ndims, "").unwrap();
+    let out_dims = ArraySliceValue::from_ptr_val(out_dims, max_ndims, None);
+
+    ctx.builder
+        .build_call(
+            ndarray_calc_broadcast_fn,
+            &[
+                lhs_dims.into(),
+                lhs_ndims.into(),
+                rhs_dims.into(),
+                rhs_ndims.into(),
+                out_dims.base_ptr(ctx, generator).into(),
+            ],
+            "",
+        )
+        .unwrap();
+
+    TypedArrayLikeAdapter::from(
+        out_dims,
+        Box::new(|_, v| v.into_int_value()),
+        Box::new(|_, v| v.into()),
+    )
+}
+
+/// Generates a call to `__nac3_ndarray_calc_broadcast_idx`. Returns an [`ArrayAllocaValue`]
+/// containing the indices used for accessing `array` corresponding to the index of the broadcasted
+/// array `broadcast_idx`.
+pub fn call_ndarray_calc_broadcast_index<
+    'ctx,
+    G: CodeGenerator + ?Sized,
+    BroadcastIdx: UntypedArrayLikeAccessor<'ctx>,
+>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    array: NDArrayValue<'ctx>,
+    broadcast_idx: &BroadcastIdx,
+) -> TypedArrayLikeAdapter<'ctx, IntValue<'ctx>> {
+    let llvm_i32 = ctx.ctx.i32_type();
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let llvm_pi32 = llvm_i32.ptr_type(AddressSpace::default());
+    let llvm_pusize = llvm_usize.ptr_type(AddressSpace::default());
+
+    let ndarray_calc_broadcast_fn_name = match llvm_usize.get_bit_width() {
+        32 => "__nac3_ndarray_calc_broadcast_idx",
+        64 => "__nac3_ndarray_calc_broadcast_idx64",
+        bw => codegen_unreachable!(ctx, "Unsupported size type bit width: {}", bw),
+    };
+    let ndarray_calc_broadcast_fn =
+        ctx.module.get_function(ndarray_calc_broadcast_fn_name).unwrap_or_else(|| {
+            let fn_type = llvm_usize.fn_type(
+                &[llvm_pusize.into(), llvm_usize.into(), llvm_pi32.into(), llvm_pi32.into()],
+                false,
+            );
+
+            ctx.module.add_function(ndarray_calc_broadcast_fn_name, fn_type, None)
+        });
+
+    let broadcast_size = broadcast_idx.size(ctx, generator);
+    let out_idx = ctx.builder.build_array_alloca(llvm_i32, broadcast_size, "").unwrap();
+
+    let array_dims = array.shape().base_ptr(ctx, generator);
+    let array_ndims = array.load_ndims(ctx);
+    let broadcast_idx_ptr = unsafe {
+        broadcast_idx.ptr_offset_unchecked(ctx, generator, &llvm_usize.const_zero(), None)
+    };
+
+    ctx.builder
+        .build_call(
+            ndarray_calc_broadcast_fn,
+            &[array_dims.into(), array_ndims.into(), broadcast_idx_ptr.into(), out_idx.into()],
+            "",
+        )
+        .unwrap();
+
+    TypedArrayLikeAdapter::from(
+        ArraySliceValue::from_ptr_val(out_idx, broadcast_size, None),
+        Box::new(|_, v| v.into_int_value()),
+        Box::new(|_, v| v.into()),
+    )
+}

nac3core/src/codegen/irrt/range.rs

@@ -0,0 +1,42 @@
+use inkwell::{
+    values::{BasicValueEnum, CallSiteValue, IntValue},
+    IntPredicate,
+};
+use itertools::Either;
+
+use crate::codegen::{CodeGenContext, CodeGenerator};
+
+pub fn calculate_len_for_slice_range<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    start: IntValue<'ctx>,
+    end: IntValue<'ctx>,
+    step: IntValue<'ctx>,
+) -> IntValue<'ctx> {
+    const SYMBOL: &str = "__nac3_range_slice_len";
+    let len_func = ctx.module.get_function(SYMBOL).unwrap_or_else(|| {
+        let i32_t = ctx.ctx.i32_type();
+        let fn_t = i32_t.fn_type(&[i32_t.into(), i32_t.into(), i32_t.into()], false);
+        ctx.module.add_function(SYMBOL, fn_t, None)
+    });
+
+    // assert step != 0, throw exception if not
+    let not_zero = ctx
+        .builder
+        .build_int_compare(IntPredicate::NE, step, step.get_type().const_zero(), "range_step_ne")
+        .unwrap();
+    ctx.make_assert(
+        generator,
+        not_zero,
+        "0:ValueError",
+        "step must not be zero",
+        [None, None, None],
+        ctx.current_loc,
+    );
+    ctx.builder
+        .build_call(len_func, &[start.into(), end.into(), step.into()], "calc_len")
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_int_value))
+        .map(Either::unwrap_left)
+        .unwrap()
+}

nac3core/src/codegen/irrt/slice.rs

@@ -0,0 +1,39 @@
+use inkwell::values::{BasicValueEnum, CallSiteValue, IntValue};
+use itertools::Either;
+
+use nac3parser::ast::Expr;
+
+use crate::{
+    codegen::{CodeGenContext, CodeGenerator},
+    typecheck::typedef::Type,
+};
+
+/// this function allows index out of range, since python
+/// allows index out of range in slice (`a = [1,2,3]; a[1:10] == [2,3]`).
+pub fn handle_slice_index_bound<'ctx, G: CodeGenerator>(
+    i: &Expr<Option<Type>>,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    generator: &mut G,
+    length: IntValue<'ctx>,
+) -> Result<Option<IntValue<'ctx>>, String> {
+    const SYMBOL: &str = "__nac3_slice_index_bound";
+    let func = ctx.module.get_function(SYMBOL).unwrap_or_else(|| {
+        let i32_t = ctx.ctx.i32_type();
+        let fn_t = i32_t.fn_type(&[i32_t.into(), i32_t.into()], false);
+        ctx.module.add_function(SYMBOL, fn_t, None)
+    });
+
+    let i = if let Some(v) = generator.gen_expr(ctx, i)? {
+        v.to_basic_value_enum(ctx, generator, i.custom.unwrap())?
+    } else {
+        return Ok(None);
+    };
+    Ok(Some(
+        ctx.builder
+            .build_call(func, &[i.into(), length.into()], "bounded_ind")
+            .map(CallSiteValue::try_as_basic_value)
+            .map(|v| v.map_left(BasicValueEnum::into_int_value))
+            .map(Either::unwrap_left)
+            .unwrap(),
+    ))
+}

nac3core/src/codegen/llvm_intrinsics.rs

@@ -1,12 +1,14 @@
-use crate::codegen::CodeGenContext;
+use inkwell::{
-use inkwell::context::Context;
+    context::Context,
-use inkwell::intrinsics::Intrinsic;
+    intrinsics::Intrinsic,
-use inkwell::types::AnyTypeEnum::IntType;
+    types::{AnyTypeEnum::IntType, FloatType},
-use inkwell::types::FloatType;
+    values::{BasicValueEnum, CallSiteValue, FloatValue, IntValue, PointerValue},
-use inkwell::values::{BasicValueEnum, CallSiteValue, FloatValue, IntValue, PointerValue};
+    AddressSpace,
-use inkwell::AddressSpace;
+};
 use itertools::Either;
 
+use super::CodeGenContext;
+
 /// Returns the string representation for the floating-point type `ft` when used in intrinsic
 /// functions.
 fn get_float_intrinsic_repr(ctx: &Context, ft: FloatType) -> &'static str {
@@ -183,7 +185,7 @@ pub fn call_memcpy_generic<'ctx>(
         dest
     } else {
         ctx.builder
-            .build_bitcast(dest, llvm_p0i8, "")
+            .build_bit_cast(dest, llvm_p0i8, "")
             .map(BasicValueEnum::into_pointer_value)
             .unwrap()
     };
@@ -191,7 +193,7 @@ pub fn call_memcpy_generic<'ctx>(
         src
     } else {
         ctx.builder
-            .build_bitcast(src, llvm_p0i8, "")
+            .build_bit_cast(src, llvm_p0i8, "")
             .map(BasicValueEnum::into_pointer_value)
             .unwrap()
     };
@@ -199,6 +201,49 @@ pub fn call_memcpy_generic<'ctx>(
     call_memcpy(ctx, dest, src, len, is_volatile);
 }
 
+/// Invokes the `llvm.memcpy` intrinsic.
+///
+/// Unlike [`call_memcpy`], this function accepts any type of pointer value. If `dest` or `src` is
+/// not a pointer to an integer, the pointer(s) will be cast to `i8*` before invoking `memcpy`.
+/// Moreover, `len` now refers to the number of elements to copy (rather than number of bytes to
+/// copy).
+pub fn call_memcpy_generic_array<'ctx>(
+    ctx: &CodeGenContext<'ctx, '_>,
+    dest: PointerValue<'ctx>,
+    src: PointerValue<'ctx>,
+    len: IntValue<'ctx>,
+    is_volatile: IntValue<'ctx>,
+) {
+    let llvm_i8 = ctx.ctx.i8_type();
+    let llvm_p0i8 = llvm_i8.ptr_type(AddressSpace::default());
+    let llvm_sizeof_expr_t = llvm_i8.size_of().get_type();
+
+    let dest_elem_t = dest.get_type().get_element_type();
+    let src_elem_t = src.get_type().get_element_type();
+
+    let dest = if matches!(dest_elem_t, IntType(t) if t.get_bit_width() == 8) {
+        dest
+    } else {
+        ctx.builder
+            .build_bit_cast(dest, llvm_p0i8, "")
+            .map(BasicValueEnum::into_pointer_value)
+            .unwrap()
+    };
+    let src = if matches!(src_elem_t, IntType(t) if t.get_bit_width() == 8) {
+        src
+    } else {
+        ctx.builder
+            .build_bit_cast(src, llvm_p0i8, "")
+            .map(BasicValueEnum::into_pointer_value)
+            .unwrap()
+    };
+
+    let len = ctx.builder.build_int_z_extend_or_bit_cast(len, llvm_sizeof_expr_t, "").unwrap();
+    let len = ctx.builder.build_int_mul(len, src_elem_t.size_of().unwrap(), "").unwrap();
+
+    call_memcpy(ctx, dest, src, len, is_volatile);
+}
+
 /// Macro to find and generate build call for llvm intrinsic (body of llvm intrinsic function)
 ///
 /// Arguments:
@@ -341,3 +386,25 @@ pub fn call_float_powi<'ctx>(
         .map(Either::unwrap_left)
         .unwrap()
 }
+
+/// Invokes the [`llvm.ctpop`](https://llvm.org/docs/LangRef.html#llvm-ctpop-intrinsic) intrinsic.
+pub fn call_int_ctpop<'ctx>(
+    ctx: &CodeGenContext<'ctx, '_>,
+    src: IntValue<'ctx>,
+    name: Option<&str>,
+) -> IntValue<'ctx> {
+    const FN_NAME: &str = "llvm.ctpop";
+
+    let llvm_src_t = src.get_type();
+
+    let intrinsic_fn = Intrinsic::find(FN_NAME)
+        .and_then(|intrinsic| intrinsic.get_declaration(&ctx.module, &[llvm_src_t.into()]))
+        .unwrap();
+
+    ctx.builder
+        .build_call(intrinsic_fn, &[src.into()], name.unwrap_or_default())
+        .map(CallSiteValue::try_as_basic_value)
+        .map(|v| v.map_left(BasicValueEnum::into_int_value))
+        .map(Either::unwrap_left)
+        .unwrap()
+}

nac3core/src/codegen/mod.rs

@@ -1,12 +1,12 @@
-use crate::{
+use std::{
-    codegen::classes::{ListType, NDArrayType, ProxyType, RangeType},
+    collections::{HashMap, HashSet},
-    symbol_resolver::{StaticValue, SymbolResolver},
+    sync::{
-    toplevel::{helper::PrimDef, numpy::unpack_ndarray_var_tys, TopLevelContext, TopLevelDef},
+        atomic::{AtomicBool, Ordering},
-    typecheck::{
+        Arc,
-        type_inferencer::{CodeLocation, PrimitiveStore},
-        typedef::{CallId, FuncArg, Type, TypeEnum, Unifier},
     },
+    thread,
 };
+
 use crossbeam::channel::{unbounded, Receiver, Sender};
 use inkwell::{
     attributes::{Attribute, AttributeLoc},
@@ -24,17 +24,27 @@ use inkwell::{
     AddressSpace, IntPredicate, OptimizationLevel,
 };
 use itertools::Itertools;
-use nac3parser::ast::{Location, Stmt, StrRef};
 use parking_lot::{Condvar, Mutex};
-use std::collections::{HashMap, HashSet};
+
-use std::sync::{
+use nac3parser::ast::{Location, Stmt, StrRef};
-    atomic::{AtomicBool, Ordering},
+
-    Arc,
+use crate::{
+    symbol_resolver::{StaticValue, SymbolResolver},
+    toplevel::{
+        helper::{extract_ndims, PrimDef},
+        numpy::unpack_ndarray_var_tys,
+        TopLevelContext, TopLevelDef,
+    },
+    typecheck::{
+        type_inferencer::{CodeLocation, PrimitiveStore},
+        typedef::{CallId, FuncArg, Type, TypeEnum, Unifier},
+    },
 };
-use std::thread;
+use concrete_type::{ConcreteType, ConcreteTypeEnum, ConcreteTypeStore};
+pub use generator::{CodeGenerator, DefaultCodeGenerator};
+use types::{ndarray::NDArrayType, ListType, ProxyType, RangeType};
 
 pub mod builtin_fns;
-pub mod classes;
 pub mod concrete_type;
 pub mod expr;
 pub mod extern_fns;
@@ -43,12 +53,27 @@ pub mod irrt;
 pub mod llvm_intrinsics;
 pub mod numpy;
 pub mod stmt;
+pub mod types;
+pub mod values;
 
 #[cfg(test)]
 mod test;
 
-use concrete_type::{ConcreteType, ConcreteTypeEnum, ConcreteTypeStore};
+mod macros {
-pub use generator::{CodeGenerator, DefaultCodeGenerator};
+    /// Codegen-variant of [`std::unreachable`] which accepts an instance of [`CodeGenContext`] as
+    /// its first argument to provide Python source information to indicate the codegen location
+    /// causing the assertion.
+    macro_rules! codegen_unreachable {
+        ($ctx:expr $(,)?) => {
+            std::unreachable!("unreachable code while processing {}", &$ctx.current_loc)
+        };
+        ($ctx:expr, $($arg:tt)*) => {
+            std::unreachable!("unreachable code while processing {}: {}", &$ctx.current_loc, std::format!("{}", std::format_args!($($arg)+)))
+        };
+    }
+
+    pub(crate) use codegen_unreachable;
+}
 
 #[derive(Default)]
 pub struct StaticValueStore {
@@ -489,12 +514,13 @@ fn get_llvm_type<'ctx, G: CodeGenerator + ?Sized>(
                         }
 
                         TObj { obj_id, .. } if *obj_id == PrimDef::NDArray.id() => {
-                            let (dtype, _) = unpack_ndarray_var_tys(unifier, ty);
+                            let (dtype, ndims) = unpack_ndarray_var_tys(unifier, ty);
+                            let ndims = extract_ndims(unifier, ndims);
                             let element_type = get_llvm_type(
                                 ctx, module, generator, unifier, top_level, type_cache, dtype,
                             );
 
-                            NDArrayType::new(generator, ctx, element_type).as_base_type().into()
+                            NDArrayType::new(generator, ctx, element_type, Some(ndims)).as_base_type().into()
                         }
 
                         _ => unreachable!(
@@ -832,10 +858,9 @@ pub fn gen_func_impl<
     builder.position_at_end(init_bb);
     let body_bb = context.append_basic_block(fn_val, "body");
 
+    // Store non-vararg argument values into local variables
     let mut var_assignment = HashMap::new();
     let offset = u32::from(has_sret);
-
-    // Store non-vararg argument values into local variables
     for (n, arg) in args.iter().enumerate().filter(|(_, arg)| !arg.is_vararg) {
         let param = fn_val.get_nth_param((n as u32) + offset).unwrap();
         let local_type = get_llvm_type(
@@ -1099,3 +1124,106 @@ fn gen_in_range_check<'ctx>(
 fn get_va_count_arg_name(arg_name: StrRef) -> StrRef {
     format!("__{}_va_count", &arg_name).into()
 }
+
+/// Returns the alignment of the type.
+///
+/// This is necessary as `get_alignment` is not implemented as part of [`BasicType`].
+pub fn get_type_alignment<'ctx>(ty: impl Into<BasicTypeEnum<'ctx>>) -> IntValue<'ctx> {
+    match ty.into() {
+        BasicTypeEnum::ArrayType(ty) => ty.get_alignment(),
+        BasicTypeEnum::FloatType(ty) => ty.get_alignment(),
+        BasicTypeEnum::IntType(ty) => ty.get_alignment(),
+        BasicTypeEnum::PointerType(ty) => ty.get_alignment(),
+        BasicTypeEnum::StructType(ty) => ty.get_alignment(),
+        BasicTypeEnum::VectorType(ty) => ty.get_alignment(),
+    }
+}
+
+/// Inserts an `alloca` instruction with allocation `size` given in bytes and the alignment of the
+/// given type.
+///
+/// The returned [`PointerValue`] will have a type of `i8*`, a size of at least `size`, and will be
+/// aligned with the alignment of `align_ty`.
+pub fn type_aligned_alloca<'ctx, G: CodeGenerator + ?Sized>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    align_ty: impl Into<BasicTypeEnum<'ctx>>,
+    size: IntValue<'ctx>,
+    name: Option<&str>,
+) -> PointerValue<'ctx> {
+    /// Round `val` up to its modulo `power_of_two`.
+    fn round_up<'ctx>(
+        ctx: &CodeGenContext<'ctx, '_>,
+        val: IntValue<'ctx>,
+        power_of_two: IntValue<'ctx>,
+    ) -> IntValue<'ctx> {
+        debug_assert_eq!(
+            val.get_type().get_bit_width(),
+            power_of_two.get_type().get_bit_width(),
+            "`val` ({}) and `power_of_two` ({}) must be the same type",
+            val.get_type(),
+            power_of_two.get_type(),
+        );
+
+        let llvm_val_t = val.get_type();
+
+        let max_rem =
+            ctx.builder.build_int_sub(power_of_two, llvm_val_t.const_int(1, false), "").unwrap();
+        ctx.builder
+            .build_and(
+                ctx.builder.build_int_add(val, max_rem, "").unwrap(),
+                ctx.builder.build_not(max_rem, "").unwrap(),
+                "",
+            )
+            .unwrap()
+    }
+
+    let llvm_i8 = ctx.ctx.i8_type();
+    let llvm_pi8 = llvm_i8.ptr_type(AddressSpace::default());
+    let llvm_usize = generator.get_size_type(ctx.ctx);
+    let align_ty = align_ty.into();
+
+    let size = ctx.builder.build_int_truncate_or_bit_cast(size, llvm_usize, "").unwrap();
+
+    debug_assert_eq!(
+        size.get_type().get_bit_width(),
+        llvm_usize.get_bit_width(),
+        "Expected size_t ({}) for parameter `size` of `aligned_alloca`, got {}",
+        llvm_usize,
+        size.get_type(),
+    );
+
+    let alignment = get_type_alignment(align_ty);
+    let alignment = ctx.builder.build_int_truncate_or_bit_cast(alignment, llvm_usize, "").unwrap();
+
+    if ctx.registry.llvm_options.opt_level == OptimizationLevel::None {
+        let alignment_bitcount = llvm_intrinsics::call_int_ctpop(ctx, alignment, None);
+
+        ctx.make_assert(
+            generator,
+            ctx.builder
+                .build_int_compare(
+                    IntPredicate::EQ,
+                    alignment_bitcount,
+                    alignment_bitcount.get_type().const_int(1, false),
+                    "",
+                )
+                .unwrap(),
+            "0:AssertionError",
+            "Expected power-of-two alignment for aligned_alloca, got {0}",
+            [Some(alignment), None, None],
+            ctx.current_loc,
+        );
+    }
+
+    let buffer_size = round_up(ctx, size, alignment);
+    let aligned_slices = ctx.builder.build_int_unsigned_div(buffer_size, alignment, "").unwrap();
+
+    // Just to be absolutely sure, alloca in [i8 x alignment] slices
+    let buffer = ctx.builder.build_array_alloca(align_ty, aligned_slices, "").unwrap();
+
+    ctx.builder
+        .build_bit_cast(buffer, llvm_pi8, name.unwrap_or_default())
+        .map(BasicValueEnum::into_pointer_value)
+        .unwrap()
+}

nac3core/src/codegen/stmt.rs

@@ -1,21 +1,3 @@
-use super::{
-    super::symbol_resolver::ValueEnum,
-    expr::destructure_range,
-    irrt::{handle_slice_indices, list_slice_assignment},
-    CodeGenContext, CodeGenerator,
-};
-use crate::{
-    codegen::{
-        classes::{ArrayLikeIndexer, ArraySliceValue, ListValue, RangeValue},
-        expr::gen_binop_expr,
-        gen_in_range_check,
-    },
-    toplevel::{DefinitionId, TopLevelDef},
-    typecheck::{
-        magic_methods::Binop,
-        typedef::{iter_type_vars, FunSignature, Type, TypeEnum},
-    },
-};
 use inkwell::{
     attributes::{Attribute, AttributeLoc},
     basic_block::BasicBlock,
@@ -24,10 +6,28 @@ use inkwell::{
     IntPredicate,
 };
 use itertools::{izip, Itertools};
+
 use nac3parser::ast::{
     Constant, ExcepthandlerKind, Expr, ExprKind, Location, Stmt, StmtKind, StrRef,
 };
 
+use super::{
+    expr::{destructure_range, gen_binop_expr},
+    gen_in_range_check,
+    irrt::{handle_slice_indices, list_slice_assignment},
+    macros::codegen_unreachable,
+    values::{ArrayLikeIndexer, ArraySliceValue, ListValue, RangeValue},
+    CodeGenContext, CodeGenerator,
+};
+use crate::{
+    symbol_resolver::ValueEnum,
+    toplevel::{DefinitionId, TopLevelDef},
+    typecheck::{
+        magic_methods::Binop,
+        typedef::{iter_type_vars, FunSignature, Type, TypeEnum},
+    },
+};
+
 /// See [`CodeGenerator::gen_var_alloc`].
 pub fn gen_var<'ctx>(
     ctx: &mut CodeGenContext<'ctx, '_>,
@@ -121,7 +121,7 @@ pub fn gen_store_target<'ctx, G: CodeGenerator>(
                 return Ok(None);
             };
             let BasicValueEnum::PointerValue(ptr) = val else {
-                unreachable!();
+                codegen_unreachable!(ctx);
             };
             unsafe {
                 ctx.builder.build_in_bounds_gep(
@@ -135,7 +135,7 @@ pub fn gen_store_target<'ctx, G: CodeGenerator>(
             }
             .unwrap()
         }
-        _ => unreachable!(),
+        _ => codegen_unreachable!(ctx),
     }))
 }
 
@@ -176,6 +176,14 @@ pub fn gen_assign<'ctx, G: CodeGenerator>(
                 }
             }
             let val = value.to_basic_value_enum(ctx, generator, target.custom.unwrap())?;
+
+            // Perform i1 <-> i8 conversion as needed
+            let val = if ctx.unifier.unioned(target.custom.unwrap(), ctx.primitives.bool) {
+                generator.bool_to_i8(ctx, val.into_int_value()).into()
+            } else {
+                val
+            };
+
             ctx.builder.build_store(ptr, val).unwrap();
         }
     };
@@ -193,12 +201,12 @@ pub fn gen_assign_target_list<'ctx, G: CodeGenerator>(
     // Deconstruct the tuple `value`
     let BasicValueEnum::StructValue(tuple) = value.to_basic_value_enum(ctx, generator, value_ty)?
     else {
-        unreachable!()
+        codegen_unreachable!(ctx)
     };
 
     // NOTE: Currently, RHS's type is forced to be a Tuple by the type inferencer.
     let TypeEnum::TTuple { ty: tuple_tys, .. } = &*ctx.unifier.get_ty(value_ty) else {
-        unreachable!();
+        codegen_unreachable!(ctx);
     };
 
     assert_eq!(tuple.get_type().count_fields() as usize, tuple_tys.len());
@@ -258,7 +266,7 @@ pub fn gen_assign_target_list<'ctx, G: CodeGenerator>(
             // Now assign with that sub-tuple to the starred target.
             generator.gen_assign(ctx, target, ValueEnum::Dynamic(sub_tuple_val), sub_tuple_ty)?;
         } else {
-            unreachable!() // The typechecker ensures this
+            codegen_unreachable!(ctx) // The typechecker ensures this
         }
 
         // Handle assignment after the starred target
@@ -302,11 +310,13 @@ pub fn gen_setitem<'ctx, G: CodeGenerator>(
                 .unwrap()
                 .to_basic_value_enum(ctx, generator, target_ty)?
                 .into_pointer_value();
-            let target = ListValue::from_ptr_val(target, llvm_usize, None);
+            let target = ListValue::from_pointer_value(target, llvm_usize, None);
 
             if let ExprKind::Slice { .. } = &key.node {
                 // Handle assigning to a slice
-                let ExprKind::Slice { lower, upper, step } = &key.node else { unreachable!() };
+                let ExprKind::Slice { lower, upper, step } = &key.node else {
+                    codegen_unreachable!(ctx)
+                };
                 let Some((start, end, step)) = handle_slice_indices(
                     lower,
                     upper,
@@ -321,7 +331,7 @@ pub fn gen_setitem<'ctx, G: CodeGenerator>(
 
                 let value =
                     value.to_basic_value_enum(ctx, generator, value_ty)?.into_pointer_value();
-                let value = ListValue::from_ptr_val(value, llvm_usize, None);
+                let value = ListValue::from_pointer_value(value, llvm_usize, None);
 
                 let target_item_ty = ctx.get_llvm_type(generator, target_item_ty);
                 let Some(src_ind) = handle_slice_indices(
@@ -416,7 +426,9 @@ pub fn gen_for<G: CodeGenerator>(
     ctx: &mut CodeGenContext<'_, '_>,
     stmt: &Stmt<Option<Type>>,
 ) -> Result<(), String> {
-    let StmtKind::For { iter, target, body, orelse, .. } = &stmt.node else { unreachable!() };
+    let StmtKind::For { iter, target, body, orelse, .. } = &stmt.node else {
+        codegen_unreachable!(ctx)
+    };
 
     // var_assignment static values may be changed in another branch
     // if so, remove the static value as it may not be correct in this branch
@@ -451,14 +463,15 @@ pub fn gen_for<G: CodeGenerator>(
         TypeEnum::TObj { obj_id, .. }
             if *obj_id == ctx.primitives.range.obj_id(&ctx.unifier).unwrap() =>
         {
-            let iter_val = RangeValue::from_ptr_val(iter_val.into_pointer_value(), Some("range"));
+            let iter_val =
+                RangeValue::from_pointer_value(iter_val.into_pointer_value(), Some("range"));
             // Internal variable for loop; Cannot be assigned
             let i = generator.gen_var_alloc(ctx, int32.into(), Some("for.i.addr"))?;
             // Variable declared in "target" expression of the loop; Can be reassigned *or* shadowed
             let Some(target_i) =
                 generator.gen_store_target(ctx, target, Some("for.target.addr"))?
             else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
             let (start, stop, step) = destructure_range(ctx, iter_val);
 
@@ -901,7 +914,7 @@ pub fn gen_while<G: CodeGenerator>(
     ctx: &mut CodeGenContext<'_, '_>,
     stmt: &Stmt<Option<Type>>,
 ) -> Result<(), String> {
-    let StmtKind::While { test, body, orelse, .. } = &stmt.node else { unreachable!() };
+    let StmtKind::While { test, body, orelse, .. } = &stmt.node else { codegen_unreachable!(ctx) };
 
     // var_assignment static values may be changed in another branch
     // if so, remove the static value as it may not be correct in this branch
@@ -931,7 +944,7 @@ pub fn gen_while<G: CodeGenerator>(
 
         return Ok(());
     };
-    let BasicValueEnum::IntValue(test) = test else { unreachable!() };
+    let BasicValueEnum::IntValue(test) = test else { codegen_unreachable!(ctx) };
 
     ctx.builder
         .build_conditional_branch(generator.bool_to_i1(ctx, test), body_bb, orelse_bb)
@@ -1079,7 +1092,7 @@ pub fn gen_if<G: CodeGenerator>(
     ctx: &mut CodeGenContext<'_, '_>,
     stmt: &Stmt<Option<Type>>,
 ) -> Result<(), String> {
-    let StmtKind::If { test, body, orelse, .. } = &stmt.node else { unreachable!() };
+    let StmtKind::If { test, body, orelse, .. } = &stmt.node else { codegen_unreachable!(ctx) };
 
     // var_assignment static values may be changed in another branch
     // if so, remove the static value as it may not be correct in this branch
@@ -1202,11 +1215,11 @@ pub fn exn_constructor<'ctx>(
     let zelf_id = if let TypeEnum::TObj { obj_id, .. } = &*ctx.unifier.get_ty(zelf_ty) {
         obj_id.0
     } else {
-        unreachable!()
+        codegen_unreachable!(ctx)
     };
     let defs = ctx.top_level.definitions.read();
     let def = defs[zelf_id].read();
-    let TopLevelDef::Class { name: zelf_name, .. } = &*def else { unreachable!() };
+    let TopLevelDef::Class { name: zelf_name, .. } = &*def else { codegen_unreachable!(ctx) };
     let exception_name = format!("{}:{}", ctx.resolver.get_exception_id(zelf_id), zelf_name);
     unsafe {
         let id_ptr = ctx.builder.build_in_bounds_gep(zelf, &[zero, zero], "exn.id").unwrap();
@@ -1314,7 +1327,7 @@ pub fn gen_try<'ctx, 'a, G: CodeGenerator>(
     target: &Stmt<Option<Type>>,
 ) -> Result<(), String> {
     let StmtKind::Try { body, handlers, orelse, finalbody, .. } = &target.node else {
-        unreachable!()
+        codegen_unreachable!(ctx)
     };
 
     // if we need to generate anything related to exception, we must have personality defined
@@ -1391,7 +1404,7 @@ pub fn gen_try<'ctx, 'a, G: CodeGenerator>(
             if let TypeEnum::TObj { obj_id, .. } = &*ctx.unifier.get_ty(type_.custom.unwrap()) {
                 *obj_id
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
         let exception_name = format!("{}:{}", ctx.resolver.get_exception_id(obj_id.0), exn_name);
         let exn_id = ctx.resolver.get_string_id(&exception_name);
@@ -1663,6 +1676,23 @@ pub fn gen_return<G: CodeGenerator>(
     } else {
         None
     };
+
+    // Remap boolean return type into i1
+    let value = value.map(|ret_val| {
+        // The "return type" of a sret function is in the first parameter
+        let expected_ty = if ctx.need_sret {
+            func.get_type().get_param_types()[0]
+        } else {
+            func.get_type().get_return_type().unwrap()
+        };
+
+        if matches!(expected_ty, BasicTypeEnum::IntType(ty) if ty.get_bit_width() == 1) {
+            generator.bool_to_i1(ctx, ret_val.into_int_value()).into()
+        } else {
+            ret_val
+        }
+    });
+
     if let Some(return_target) = ctx.return_target {
         if let Some(value) = value {
             ctx.builder.build_store(ctx.return_buffer.unwrap(), value).unwrap();
@@ -1673,25 +1703,6 @@ pub fn gen_return<G: CodeGenerator>(
         ctx.builder.build_store(ctx.return_buffer.unwrap(), value.unwrap()).unwrap();
         ctx.builder.build_return(None).unwrap();
     } else {
-        // Remap boolean return type into i1
-        let value = value.map(|v| {
-            let expected_ty = func.get_type().get_return_type().unwrap();
-            let ret_val = v.as_basic_value_enum();
-
-            if expected_ty.is_int_type() && ret_val.is_int_value() {
-                let ret_type = expected_ty.into_int_type();
-                let ret_val = ret_val.into_int_value();
-
-                if ret_type.get_bit_width() == 1 && ret_val.get_type().get_bit_width() != 1 {
-                    generator.bool_to_i1(ctx, ret_val)
-                } else {
-                    ret_val
-                }
-                .into()
-            } else {
-                ret_val
-            }
-        });
         let value = value.as_ref().map(|v| v as &dyn BasicValue);
         ctx.builder.build_return(value).unwrap();
     }
@@ -1760,7 +1771,30 @@ pub fn gen_stmt<G: CodeGenerator>(
         StmtKind::Try { .. } => gen_try(generator, ctx, stmt)?,
         StmtKind::Raise { exc, .. } => {
             if let Some(exc) = exc {
-                let exc = if let Some(v) = generator.gen_expr(ctx, exc)? {
+                let exn = if let ExprKind::Name { id, .. } = &exc.node {
+                    // Handle "raise Exception" short form
+                    let def_id = ctx.resolver.get_identifier_def(*id).map_err(|e| {
+                        format!("{} (at {})", e.iter().next().unwrap(), exc.location)
+                    })?;
+                    let def = ctx.top_level.definitions.read();
+                    let TopLevelDef::Class { constructor, .. } = *def[def_id.0].read() else {
+                        return Err(format!("Failed to resolve symbol {id} (at {})", exc.location));
+                    };
+
+                    let TypeEnum::TFunc(signature) =
+                        ctx.unifier.get_ty(constructor.unwrap()).as_ref().clone()
+                    else {
+                        return Err(format!("Failed to resolve symbol {id} (at {})", exc.location));
+                    };
+
+                    generator
+                        .gen_call(ctx, None, (&signature, def_id), Vec::default())?
+                        .map(Into::into)
+                } else {
+                    generator.gen_expr(ctx, exc)?
+                };
+
+                let exc = if let Some(v) = exn {
                     v.to_basic_value_enum(ctx, generator, exc.custom.unwrap())?
                 } else {
                     return Ok(());
@@ -1795,6 +1829,37 @@ pub fn gen_stmt<G: CodeGenerator>(
                 stmt.location,
             );
         }
+        StmtKind::Global { names, .. } => {
+            let registered_globals = ctx
+                .top_level
+                .definitions
+                .read()
+                .iter()
+                .filter_map(|def| {
+                    if let TopLevelDef::Variable { simple_name, ty, .. } = &*def.read() {
+                        Some((*simple_name, *ty))
+                    } else {
+                        None
+                    }
+                })
+                .collect_vec();
+
+            for id in names {
+                let Some((_, ty)) = registered_globals.iter().find(|(name, _)| name == id) else {
+                    return Err(format!("{id} is not a global at {}", stmt.location));
+                };
+
+                let resolver = ctx.resolver.clone();
+                let ptr = resolver
+                    .get_symbol_value(*id, ctx, generator)
+                    .map(|val| val.to_basic_value_enum(ctx, generator, *ty))
+                    .transpose()?
+                    .map(BasicValueEnum::into_pointer_value)
+                    .unwrap();
+
+                ctx.var_assignment.insert(*id, (ptr, None, 0));
+            }
+        }
         _ => unimplemented!(),
     };
     Ok(())

nac3core/src/codegen/test.rs

@@ -1,34 +1,37 @@
-use crate::{
+use std::{
-    codegen::{
+    collections::{HashMap, HashSet},
-        classes::{ListType, NDArrayType, ProxyType, RangeType},
+    sync::Arc,
-        concrete_type::ConcreteTypeStore,
-        CodeGenContext, CodeGenLLVMOptions, CodeGenTargetMachineOptions, CodeGenTask,
-        CodeGenerator, DefaultCodeGenerator, WithCall, WorkerRegistry,
-    },
-    symbol_resolver::{SymbolResolver, ValueEnum},
-    toplevel::{
-        composer::{ComposerConfig, TopLevelComposer},
-        DefinitionId, FunInstance, TopLevelContext, TopLevelDef,
-    },
-    typecheck::{
-        type_inferencer::{FunctionData, Inferencer, PrimitiveStore},
-        typedef::{FunSignature, FuncArg, Type, TypeEnum, Unifier, VarMap},
-    },
 };
+
 use indexmap::IndexMap;
 use indoc::indoc;
 use inkwell::{
     targets::{InitializationConfig, Target},
     OptimizationLevel,
 };
-use nac3parser::ast::FileName;
 use nac3parser::{
-    ast::{fold::Fold, StrRef},
+    ast::{fold::Fold, FileName, StrRef},
     parser::parse_program,
 };
 use parking_lot::RwLock;
-use std::collections::{HashMap, HashSet};
+
-use std::sync::Arc;
+use super::{
+    concrete_type::ConcreteTypeStore,
+    types::{ndarray::NDArrayType, ListType, ProxyType, RangeType},
+    CodeGenContext, CodeGenLLVMOptions, CodeGenTargetMachineOptions, CodeGenTask, CodeGenerator,
+    DefaultCodeGenerator, WithCall, WorkerRegistry,
+};
+use crate::{
+    symbol_resolver::{SymbolResolver, ValueEnum},
+    toplevel::{
+        composer::{ComposerConfig, TopLevelComposer},
+        DefinitionId, FunInstance, TopLevelContext, TopLevelDef,
+    },
+    typecheck::{
+        type_inferencer::{FunctionData, IdentifierInfo, Inferencer, PrimitiveStore},
+        typedef::{FunSignature, FuncArg, Type, TypeEnum, Unifier, VarMap},
+    },
+};
 
 struct Resolver {
     id_to_type: HashMap<StrRef, Type>,
@@ -64,6 +67,7 @@ impl SymbolResolver for Resolver {
         &self,
         _: StrRef,
         _: &mut CodeGenContext<'ctx, '_>,
+        _: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>> {
         unimplemented!()
     }
@@ -138,7 +142,8 @@ fn test_primitives() {
     };
     let mut virtual_checks = Vec::new();
     let mut calls = HashMap::new();
-    let mut identifiers: HashSet<_> = ["a".into(), "b".into()].into();
+    let mut identifiers: HashMap<_, _> =
+        ["a".into(), "b".into()].map(|id| (id, IdentifierInfo::default())).into();
     let mut inferencer = Inferencer {
         top_level: &top_level,
         function_data: &mut function_data,
@@ -317,7 +322,8 @@ fn test_simple_call() {
     };
     let mut virtual_checks = Vec::new();
     let mut calls = HashMap::new();
-    let mut identifiers: HashSet<_> = ["a".into(), "foo".into()].into();
+    let mut identifiers: HashMap<_, _> =
+        ["a".into(), "foo".into()].map(|id| (id, IdentifierInfo::default())).into();
     let mut inferencer = Inferencer {
         top_level: &top_level,
         function_data: &mut function_data,
@@ -446,7 +452,7 @@ fn test_classes_list_type_new() {
     let llvm_usize = generator.get_size_type(&ctx);
 
     let llvm_list = ListType::new(&generator, &ctx, llvm_i32.into());
-    assert!(ListType::is_type(llvm_list.as_base_type(), llvm_usize).is_ok());
+    assert!(ListType::is_representable(llvm_list.as_base_type(), llvm_usize).is_ok());
 }
 
 #[test]
@@ -454,7 +460,7 @@ fn test_classes_range_type_new() {
     let ctx = inkwell::context::Context::create();
 
     let llvm_range = RangeType::new(&ctx);
-    assert!(RangeType::is_type(llvm_range.as_base_type()).is_ok());
+    assert!(RangeType::is_representable(llvm_range.as_base_type()).is_ok());
 }
 
 #[test]
@@ -465,6 +471,6 @@ fn test_classes_ndarray_type_new() {
     let llvm_i32 = ctx.i32_type();
     let llvm_usize = generator.get_size_type(&ctx);
 
-    let llvm_ndarray = NDArrayType::new(&generator, &ctx, llvm_i32.into());
+    let llvm_ndarray = NDArrayType::new(&generator, &ctx, llvm_i32.into(), None);
-    assert!(NDArrayType::is_type(llvm_ndarray.as_base_type(), llvm_usize).is_ok());
+    assert!(NDArrayType::is_representable(llvm_ndarray.as_base_type(), llvm_usize).is_ok());
 }

nac3core/src/codegen/types/list.rs

@@ -0,0 +1,206 @@
+use inkwell::{
+    context::Context,
+    types::{AnyTypeEnum, BasicType, BasicTypeEnum, IntType, PointerType},
+    values::IntValue,
+    AddressSpace,
+};
+
+use super::ProxyType;
+use crate::codegen::{
+    values::{ArraySliceValue, ListValue, ProxyValue},
+    CodeGenContext, CodeGenerator,
+};
+
+/// Proxy type for a `list` type in LLVM.
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub struct ListType<'ctx> {
+    ty: PointerType<'ctx>,
+    llvm_usize: IntType<'ctx>,
+}
+
+impl<'ctx> ListType<'ctx> {
+    /// Checks whether `llvm_ty` represents a `list` type, returning [Err] if it does not.
+    pub fn is_representable(
+        llvm_ty: PointerType<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        let llvm_list_ty = llvm_ty.get_element_type();
+        let AnyTypeEnum::StructType(llvm_list_ty) = llvm_list_ty else {
+            return Err(format!("Expected struct type for `list` type, got {llvm_list_ty}"));
+        };
+        if llvm_list_ty.count_fields() != 2 {
+            return Err(format!(
+                "Expected 2 fields in `list`, got {}",
+                llvm_list_ty.count_fields()
+            ));
+        }
+
+        let list_size_ty = llvm_list_ty.get_field_type_at_index(0).unwrap();
+        let Ok(_) = PointerType::try_from(list_size_ty) else {
+            return Err(format!("Expected pointer type for `list.0`, got {list_size_ty}"));
+        };
+
+        let list_data_ty = llvm_list_ty.get_field_type_at_index(1).unwrap();
+        let Ok(list_data_ty) = IntType::try_from(list_data_ty) else {
+            return Err(format!("Expected int type for `list.1`, got {list_data_ty}"));
+        };
+        if list_data_ty.get_bit_width() != llvm_usize.get_bit_width() {
+            return Err(format!(
+                "Expected {}-bit int type for `list.1`, got {}-bit int",
+                llvm_usize.get_bit_width(),
+                list_data_ty.get_bit_width()
+            ));
+        }
+
+        Ok(())
+    }
+
+    /// Creates an LLVM type corresponding to the expected structure of a `List`.
+    #[must_use]
+    fn llvm_type(
+        ctx: &'ctx Context,
+        element_type: BasicTypeEnum<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> PointerType<'ctx> {
+        // struct List { data: T*, size: size_t }
+        let field_tys = [element_type.ptr_type(AddressSpace::default()).into(), llvm_usize.into()];
+
+        ctx.struct_type(&field_tys, false).ptr_type(AddressSpace::default())
+    }
+
+    /// Creates an instance of [`ListType`].
+    #[must_use]
+    pub fn new<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        element_type: BasicTypeEnum<'ctx>,
+    ) -> Self {
+        let llvm_usize = generator.get_size_type(ctx);
+        let llvm_list = Self::llvm_type(ctx, element_type, llvm_usize);
+
+        ListType::from_type(llvm_list, llvm_usize)
+    }
+
+    /// Creates an [`ListType`] from a [`PointerType`].
+    #[must_use]
+    pub fn from_type(ptr_ty: PointerType<'ctx>, llvm_usize: IntType<'ctx>) -> Self {
+        debug_assert!(Self::is_representable(ptr_ty, llvm_usize).is_ok());
+
+        ListType { ty: ptr_ty, llvm_usize }
+    }
+
+    /// Returns the type of the `size` field of this `list` type.
+    #[must_use]
+    pub fn size_type(&self) -> IntType<'ctx> {
+        self.as_base_type()
+            .get_element_type()
+            .into_struct_type()
+            .get_field_type_at_index(1)
+            .map(BasicTypeEnum::into_int_type)
+            .unwrap()
+    }
+
+    /// Returns the element type of this `list` type.
+    #[must_use]
+    pub fn element_type(&self) -> AnyTypeEnum<'ctx> {
+        self.as_base_type()
+            .get_element_type()
+            .into_struct_type()
+            .get_field_type_at_index(0)
+            .map(BasicTypeEnum::into_pointer_type)
+            .map(PointerType::get_element_type)
+            .unwrap()
+    }
+
+    /// Allocates an instance of [`ListValue`] as if by calling `alloca` on the base type.
+    #[must_use]
+    pub fn alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            self.raw_alloca(generator, ctx, name),
+            self.llvm_usize,
+            name,
+        )
+    }
+
+    /// Converts an existing value into a [`ListValue`].
+    #[must_use]
+    pub fn map_value(
+        &self,
+        value: <<Self as ProxyType<'ctx>>::Value as ProxyValue<'ctx>>::Base,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(value, self.llvm_usize, name)
+    }
+}
+
+impl<'ctx> ProxyType<'ctx> for ListType<'ctx> {
+    type Base = PointerType<'ctx>;
+    type Value = ListValue<'ctx>;
+
+    fn is_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: impl BasicType<'ctx>,
+    ) -> Result<(), String> {
+        if let BasicTypeEnum::PointerType(ty) = llvm_ty.as_basic_type_enum() {
+            <Self as ProxyType<'ctx>>::is_representable(generator, ctx, ty)
+        } else {
+            Err(format!("Expected pointer type, got {llvm_ty:?}"))
+        }
+    }
+
+    fn is_representable<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: Self::Base,
+    ) -> Result<(), String> {
+        Self::is_representable(llvm_ty, generator.get_size_type(ctx))
+    }
+
+    fn raw_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self::Value as ProxyValue<'ctx>>::Base {
+        generator
+            .gen_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                name,
+            )
+            .unwrap()
+    }
+
+    fn array_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        size: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> ArraySliceValue<'ctx> {
+        generator
+            .gen_array_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                size,
+                name,
+            )
+            .unwrap()
+    }
+
+    fn as_base_type(&self) -> Self::Base {
+        self.ty
+    }
+}
+
+impl<'ctx> From<ListType<'ctx>> for PointerType<'ctx> {
+    fn from(value: ListType<'ctx>) -> Self {
+        value.as_base_type()
+    }
+}

nac3core/src/codegen/types/mod.rs

@@ -0,0 +1,76 @@
+//! This module contains abstraction over all intrinsic composite types of NAC3.
+//!
+//! # `raw_alloca` vs `alloca` vs `construct`
+//!
+//! There are three ways of creating a new object instance using the abstractions provided by this
+//! module.
+//!
+//! - `raw_alloca`: Allocates the object on the stack, returning an instance of
+//!   [`impl BasicValue`][inkwell::values::BasicValue]. This is similar to a `malloc` expression in
+//!   C++ but the object is allocated on the stack.
+//! - `alloca`: Similar to `raw_alloca`, but also wraps the allocated object with
+//!   [`<Self as ProxyType<'ctx>>::Value`][ProxyValue], and returns the wrapped object. The returned
+//!   object will not initialize any value or fields. This is similar to a type-safe `malloc`
+//!   expression in C++ but the object is allocated on the stack.
+//! - `construct`: Similar to `alloca`, but performs some initialization on the value or fields of
+//!   the returned object. This is similar to a `new` expression in C++ but the object is allocated
+//!   on the stack.
+
+use inkwell::{context::Context, types::BasicType, values::IntValue};
+
+use super::{
+    values::{ArraySliceValue, ProxyValue},
+    {CodeGenContext, CodeGenerator},
+};
+pub use list::*;
+pub use range::*;
+
+mod list;
+pub mod ndarray;
+mod range;
+pub mod structure;
+pub mod utils;
+
+/// A LLVM type that is used to represent a corresponding type in NAC3.
+pub trait ProxyType<'ctx>: Into<Self::Base> {
+    /// The LLVM type of which values of this type possess. This is usually a
+    /// [LLVM pointer type][PointerType] for any non-primitive types.
+    type Base: BasicType<'ctx>;
+
+    /// The type of values represented by this type.
+    type Value: ProxyValue<'ctx, Type = Self>;
+
+    fn is_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: impl BasicType<'ctx>,
+    ) -> Result<(), String>;
+
+    /// Checks whether `llvm_ty` can be represented by this [`ProxyType`].
+    fn is_representable<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: Self::Base,
+    ) -> Result<(), String>;
+
+    /// Creates a new value of this type, returning the LLVM instance of this value.
+    fn raw_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self::Value as ProxyValue<'ctx>>::Base;
+
+    /// Creates a new array value of this type, returning an [`ArraySliceValue`] encapsulating the
+    /// resulting array.
+    fn array_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        size: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> ArraySliceValue<'ctx>;
+
+    /// Returns the [base type][Self::Base] of this proxy.
+    fn as_base_type(&self) -> Self::Base;
+}

nac3core/src/codegen/types/ndarray/contiguous.rs

@@ -0,0 +1,257 @@
+use inkwell::{
+    context::Context,
+    types::{AnyTypeEnum, BasicType, BasicTypeEnum, IntType, PointerType},
+    values::{IntValue, PointerValue},
+    AddressSpace,
+};
+use itertools::Itertools;
+
+use nac3core_derive::StructFields;
+
+use crate::{
+    codegen::{
+        types::{
+            structure::{
+                check_struct_type_matches_fields, FieldIndexCounter, StructField, StructFields,
+            },
+            ProxyType,
+        },
+        values::{ndarray::ContiguousNDArrayValue, ArraySliceValue, ProxyValue},
+        CodeGenContext, CodeGenerator,
+    },
+    toplevel::numpy::unpack_ndarray_var_tys,
+    typecheck::typedef::Type,
+};
+
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub struct ContiguousNDArrayType<'ctx> {
+    ty: PointerType<'ctx>,
+    item: BasicTypeEnum<'ctx>,
+    llvm_usize: IntType<'ctx>,
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct ContiguousNDArrayFields<'ctx> {
+    #[value_type(usize)]
+    pub ndims: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(usize.ptr_type(AddressSpace::default()))]
+    pub shape: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(i8_type().ptr_type(AddressSpace::default()))]
+    pub data: StructField<'ctx, PointerValue<'ctx>>,
+}
+
+impl<'ctx> ContiguousNDArrayFields<'ctx> {
+    #[must_use]
+    pub fn new_typed(item: BasicTypeEnum<'ctx>, llvm_usize: IntType<'ctx>) -> Self {
+        let mut counter = FieldIndexCounter::default();
+
+        ContiguousNDArrayFields {
+            ndims: StructField::create(&mut counter, "ndims", llvm_usize),
+            shape: StructField::create(
+                &mut counter,
+                "shape",
+                llvm_usize.ptr_type(AddressSpace::default()),
+            ),
+            data: StructField::create(&mut counter, "data", item.ptr_type(AddressSpace::default())),
+        }
+    }
+}
+
+impl<'ctx> ContiguousNDArrayType<'ctx> {
+    /// Checks whether `llvm_ty` represents a `ndarray` type, returning [Err] if it does not.
+    pub fn is_representable(
+        llvm_ty: PointerType<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        let ctx = llvm_ty.get_context();
+
+        let llvm_ty = llvm_ty.get_element_type();
+        let AnyTypeEnum::StructType(llvm_ty) = llvm_ty else {
+            return Err(format!(
+                "Expected struct type for `ContiguousNDArray` type, got {llvm_ty}"
+            ));
+        };
+
+        let fields = ContiguousNDArrayFields::new(ctx, llvm_usize);
+
+        check_struct_type_matches_fields(
+            fields,
+            llvm_ty,
+            "ContiguousNDArray",
+            &[(fields.data.name(), &|ty| {
+                if ty.is_pointer_type() {
+                    Ok(())
+                } else {
+                    Err(format!("Expected T* for `ContiguousNDArray.data`, got {ty}"))
+                }
+            })],
+        )
+    }
+
+    /// Returns an instance of [`StructFields`] containing all field accessors for this type.
+    #[must_use]
+    fn fields(
+        item: BasicTypeEnum<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> ContiguousNDArrayFields<'ctx> {
+        ContiguousNDArrayFields::new_typed(item, llvm_usize)
+    }
+
+    /// See [`NDArrayType::fields`].
+    // TODO: Move this into e.g. StructProxyType
+    #[must_use]
+    pub fn get_fields(&self) -> ContiguousNDArrayFields<'ctx> {
+        Self::fields(self.item, self.llvm_usize)
+    }
+
+    /// Creates an LLVM type corresponding to the expected structure of an `NDArray`.
+    #[must_use]
+    fn llvm_type(
+        ctx: &'ctx Context,
+        item: BasicTypeEnum<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> PointerType<'ctx> {
+        let field_tys =
+            Self::fields(item, llvm_usize).into_iter().map(|field| field.1).collect_vec();
+
+        ctx.struct_type(&field_tys, false).ptr_type(AddressSpace::default())
+    }
+
+    /// Creates an instance of [`ContiguousNDArrayType`].
+    #[must_use]
+    pub fn new<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        item: BasicTypeEnum<'ctx>,
+    ) -> Self {
+        let llvm_usize = generator.get_size_type(ctx);
+        let llvm_cndarray = Self::llvm_type(ctx, item, llvm_usize);
+
+        Self { ty: llvm_cndarray, item, llvm_usize }
+    }
+
+    /// Creates an [`ContiguousNDArrayType`] from a [unifier type][Type].
+    #[must_use]
+    pub fn from_unifier_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        ty: Type,
+    ) -> Self {
+        let (dtype, _) = unpack_ndarray_var_tys(&mut ctx.unifier, ty);
+
+        let llvm_dtype = ctx.get_llvm_type(generator, dtype);
+        let llvm_usize = generator.get_size_type(ctx.ctx);
+
+        Self { ty: Self::llvm_type(ctx.ctx, llvm_dtype, llvm_usize), item: llvm_dtype, llvm_usize }
+    }
+
+    /// Creates an [`ContiguousNDArrayType`] from a [`PointerType`] representing an `NDArray`.
+    #[must_use]
+    pub fn from_type(
+        ptr_ty: PointerType<'ctx>,
+        item: BasicTypeEnum<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Self {
+        debug_assert!(Self::is_representable(ptr_ty, llvm_usize).is_ok());
+
+        Self { ty: ptr_ty, item, llvm_usize }
+    }
+
+    /// Allocates an instance of [`ContiguousNDArrayValue`] as if by calling `alloca` on the base type.
+    #[must_use]
+    pub fn alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            self.raw_alloca(generator, ctx, name),
+            self.item,
+            self.llvm_usize,
+            name,
+        )
+    }
+
+    /// Converts an existing value into a [`ContiguousNDArrayValue`].
+    #[must_use]
+    pub fn map_value(
+        &self,
+        value: <<Self as ProxyType<'ctx>>::Value as ProxyValue<'ctx>>::Base,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            value,
+            self.item,
+            self.llvm_usize,
+            name,
+        )
+    }
+}
+
+impl<'ctx> ProxyType<'ctx> for ContiguousNDArrayType<'ctx> {
+    type Base = PointerType<'ctx>;
+    type Value = ContiguousNDArrayValue<'ctx>;
+
+    fn is_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: impl BasicType<'ctx>,
+    ) -> Result<(), String> {
+        if let BasicTypeEnum::PointerType(ty) = llvm_ty.as_basic_type_enum() {
+            <Self as ProxyType<'ctx>>::is_representable(generator, ctx, ty)
+        } else {
+            Err(format!("Expected pointer type, got {llvm_ty:?}"))
+        }
+    }
+
+    fn is_representable<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: Self::Base,
+    ) -> Result<(), String> {
+        Self::is_representable(llvm_ty, generator.get_size_type(ctx))
+    }
+
+    fn raw_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self::Value as ProxyValue<'ctx>>::Base {
+        generator
+            .gen_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                name,
+            )
+            .unwrap()
+    }
+
+    fn array_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        size: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> ArraySliceValue<'ctx> {
+        generator
+            .gen_array_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                size,
+                name,
+            )
+            .unwrap()
+    }
+
+    fn as_base_type(&self) -> Self::Base {
+        self.ty
+    }
+}
+
+impl<'ctx> From<ContiguousNDArrayType<'ctx>> for PointerType<'ctx> {
+    fn from(value: ContiguousNDArrayType<'ctx>) -> Self {
+        value.as_base_type()
+    }
+}

nac3core/src/codegen/types/ndarray/indexing.rs

@@ -0,0 +1,215 @@
+use inkwell::{
+    context::{AsContextRef, Context},
+    types::{AnyTypeEnum, BasicType, BasicTypeEnum, IntType, PointerType},
+    values::{IntValue, PointerValue},
+    AddressSpace,
+};
+use itertools::Itertools;
+
+use nac3core_derive::StructFields;
+
+use crate::codegen::{
+    types::{
+        structure::{check_struct_type_matches_fields, StructField, StructFields},
+        ProxyType,
+    },
+    values::{
+        ndarray::{NDIndexValue, RustNDIndex},
+        ArrayLikeIndexer, ArraySliceValue, ProxyValue,
+    },
+    CodeGenContext, CodeGenerator,
+};
+
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub struct NDIndexType<'ctx> {
+    ty: PointerType<'ctx>,
+    llvm_usize: IntType<'ctx>,
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct NDIndexStructFields<'ctx> {
+    #[value_type(i8_type())]
+    pub type_: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(i8_type().ptr_type(AddressSpace::default()))]
+    pub data: StructField<'ctx, PointerValue<'ctx>>,
+}
+
+impl<'ctx> NDIndexType<'ctx> {
+    /// Checks whether `llvm_ty` represents a `ndindex` type, returning [Err] if it does not.
+    pub fn is_representable(
+        llvm_ty: PointerType<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        let ctx = llvm_ty.get_context();
+
+        let llvm_ty = llvm_ty.get_element_type();
+        let AnyTypeEnum::StructType(llvm_ty) = llvm_ty else {
+            return Err(format!(
+                "Expected struct type for `ContiguousNDArray` type, got {llvm_ty}"
+            ));
+        };
+
+        let fields = NDIndexStructFields::new(ctx, llvm_usize);
+
+        check_struct_type_matches_fields(fields, llvm_ty, "NDIndex", &[])
+    }
+
+    #[must_use]
+    fn fields(
+        ctx: impl AsContextRef<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> NDIndexStructFields<'ctx> {
+        NDIndexStructFields::new(ctx, llvm_usize)
+    }
+
+    #[must_use]
+    pub fn get_fields(&self) -> NDIndexStructFields<'ctx> {
+        Self::fields(self.ty.get_context(), self.llvm_usize)
+    }
+
+    #[must_use]
+    fn llvm_type(ctx: &'ctx Context, llvm_usize: IntType<'ctx>) -> PointerType<'ctx> {
+        let field_tys =
+            Self::fields(ctx, llvm_usize).into_iter().map(|field| field.1).collect_vec();
+
+        ctx.struct_type(&field_tys, false).ptr_type(AddressSpace::default())
+    }
+
+    #[must_use]
+    pub fn new<G: CodeGenerator + ?Sized>(generator: &G, ctx: &'ctx Context) -> Self {
+        let llvm_usize = generator.get_size_type(ctx);
+        let llvm_ndindex = Self::llvm_type(ctx, llvm_usize);
+
+        Self { ty: llvm_ndindex, llvm_usize }
+    }
+
+    #[must_use]
+    pub fn from_type(ptr_ty: PointerType<'ctx>, llvm_usize: IntType<'ctx>) -> Self {
+        debug_assert!(Self::is_representable(ptr_ty, llvm_usize).is_ok());
+
+        Self { ty: ptr_ty, llvm_usize }
+    }
+
+    #[must_use]
+    pub fn alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            self.raw_alloca(generator, ctx, name),
+            self.llvm_usize,
+            name,
+        )
+    }
+
+    /// Serialize a list of [`RustNDIndex`] as a newly allocated LLVM array of [`NDIndexValue`].
+    #[must_use]
+    pub fn construct_ndindices<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        in_ndindices: &[RustNDIndex<'ctx>],
+    ) -> ArraySliceValue<'ctx> {
+        // Allocate the LLVM ndindices.
+        let num_ndindices = self.llvm_usize.const_int(in_ndindices.len() as u64, false);
+        let ndindices = self.array_alloca(generator, ctx, num_ndindices, None);
+
+        // Initialize all of them.
+        for (i, in_ndindex) in in_ndindices.iter().enumerate() {
+            let pndindex = unsafe {
+                ndindices.ptr_offset_unchecked(
+                    ctx,
+                    generator,
+                    &ctx.ctx.i64_type().const_int(u64::try_from(i).unwrap(), false),
+                    None,
+                )
+            };
+
+            in_ndindex.write_to_ndindex(
+                generator,
+                ctx,
+                NDIndexValue::from_pointer_value(pndindex, self.llvm_usize, None),
+            );
+        }
+
+        ndindices
+    }
+
+    #[must_use]
+    pub fn map_value(
+        &self,
+        value: <<Self as ProxyType<'ctx>>::Value as ProxyValue<'ctx>>::Base,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(value, self.llvm_usize, name)
+    }
+}
+
+impl<'ctx> ProxyType<'ctx> for NDIndexType<'ctx> {
+    type Base = PointerType<'ctx>;
+    type Value = NDIndexValue<'ctx>;
+
+    fn is_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: impl BasicType<'ctx>,
+    ) -> Result<(), String> {
+        if let BasicTypeEnum::PointerType(ty) = llvm_ty.as_basic_type_enum() {
+            <Self as ProxyType<'ctx>>::is_representable(generator, ctx, ty)
+        } else {
+            Err(format!("Expected pointer type, got {llvm_ty:?}"))
+        }
+    }
+
+    fn is_representable<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: Self::Base,
+    ) -> Result<(), String> {
+        Self::is_representable(llvm_ty, generator.get_size_type(ctx))
+    }
+
+    fn raw_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self::Value as ProxyValue<'ctx>>::Base {
+        generator
+            .gen_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                name,
+            )
+            .unwrap()
+    }
+
+    fn array_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        size: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> ArraySliceValue<'ctx> {
+        generator
+            .gen_array_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                size,
+                name,
+            )
+            .unwrap()
+    }
+
+    fn as_base_type(&self) -> Self::Base {
+        self.ty
+    }
+}
+
+impl<'ctx> From<NDIndexType<'ctx>> for PointerType<'ctx> {
+    fn from(value: NDIndexType<'ctx>) -> Self {
+        value.as_base_type()
+    }
+}

nac3core/src/codegen/types/ndarray/mod.rs

@@ -0,0 +1,469 @@
+use inkwell::{
+    context::{AsContextRef, Context},
+    types::{AnyTypeEnum, BasicType, BasicTypeEnum, IntType, PointerType},
+    values::{BasicValue, IntValue, PointerValue},
+    AddressSpace,
+};
+use itertools::Itertools;
+
+use nac3core_derive::StructFields;
+
+use super::{
+    structure::{check_struct_type_matches_fields, StructField, StructFields},
+    ProxyType,
+};
+use crate::{
+    codegen::{
+        values::{ndarray::NDArrayValue, ArraySliceValue, ProxyValue, TypedArrayLikeMutator},
+        {CodeGenContext, CodeGenerator},
+    },
+    toplevel::{helper::extract_ndims, numpy::unpack_ndarray_var_tys},
+    typecheck::typedef::Type,
+};
+pub use contiguous::*;
+pub use indexing::*;
+pub use nditer::*;
+
+mod contiguous;
+mod indexing;
+mod nditer;
+
+/// Proxy type for a `ndarray` type in LLVM.
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub struct NDArrayType<'ctx> {
+    ty: PointerType<'ctx>,
+    dtype: BasicTypeEnum<'ctx>,
+    ndims: Option<u64>,
+    llvm_usize: IntType<'ctx>,
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct NDArrayStructFields<'ctx> {
+    /// The size of each `NDArray` element in bytes.
+    #[value_type(usize)]
+    pub itemsize: StructField<'ctx, IntValue<'ctx>>,
+    /// Number of dimensions in the array.
+    #[value_type(usize)]
+    pub ndims: StructField<'ctx, IntValue<'ctx>>,
+    /// Pointer to an array containing the shape of the `NDArray`.
+    #[value_type(usize.ptr_type(AddressSpace::default()))]
+    pub shape: StructField<'ctx, PointerValue<'ctx>>,
+    /// Pointer to an array indicating the number of bytes between each element at a dimension
+    #[value_type(usize.ptr_type(AddressSpace::default()))]
+    pub strides: StructField<'ctx, PointerValue<'ctx>>,
+    /// Pointer to an array containing the array data
+    #[value_type(i8_type().ptr_type(AddressSpace::default()))]
+    pub data: StructField<'ctx, PointerValue<'ctx>>,
+}
+
+impl<'ctx> NDArrayType<'ctx> {
+    /// Checks whether `llvm_ty` represents a `ndarray` type, returning [Err] if it does not.
+    pub fn is_representable(
+        llvm_ty: PointerType<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        let ctx = llvm_ty.get_context();
+
+        let llvm_ndarray_ty = llvm_ty.get_element_type();
+        let AnyTypeEnum::StructType(llvm_ndarray_ty) = llvm_ndarray_ty else {
+            return Err(format!("Expected struct type for `NDArray` type, got {llvm_ndarray_ty}"));
+        };
+
+        check_struct_type_matches_fields(
+            Self::fields(ctx, llvm_usize),
+            llvm_ndarray_ty,
+            "NDArray",
+            &[],
+        )
+    }
+
+    /// Returns an instance of [`StructFields`] containing all field accessors for this type.
+    #[must_use]
+    fn fields(
+        ctx: impl AsContextRef<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> NDArrayStructFields<'ctx> {
+        NDArrayStructFields::new(ctx, llvm_usize)
+    }
+
+    /// See [`NDArrayType::fields`].
+    // TODO: Move this into e.g. StructProxyType
+    #[must_use]
+    pub fn get_fields(&self, ctx: impl AsContextRef<'ctx>) -> NDArrayStructFields<'ctx> {
+        Self::fields(ctx, self.llvm_usize)
+    }
+
+    /// Creates an LLVM type corresponding to the expected structure of an `NDArray`.
+    #[must_use]
+    fn llvm_type(ctx: &'ctx Context, llvm_usize: IntType<'ctx>) -> PointerType<'ctx> {
+        let field_tys =
+            Self::fields(ctx, llvm_usize).into_iter().map(|field| field.1).collect_vec();
+
+        ctx.struct_type(&field_tys, false).ptr_type(AddressSpace::default())
+    }
+
+    /// Creates an instance of [`NDArrayType`].
+    #[must_use]
+    pub fn new<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        dtype: BasicTypeEnum<'ctx>,
+        ndims: Option<u64>,
+    ) -> Self {
+        let llvm_usize = generator.get_size_type(ctx);
+        let llvm_ndarray = Self::llvm_type(ctx, llvm_usize);
+
+        NDArrayType { ty: llvm_ndarray, dtype, ndims, llvm_usize }
+    }
+
+    /// Creates an instance of [`NDArrayType`] with `ndims` of 0.
+    #[must_use]
+    pub fn new_unsized<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        dtype: BasicTypeEnum<'ctx>,
+    ) -> Self {
+        let llvm_usize = generator.get_size_type(ctx);
+        let llvm_ndarray = Self::llvm_type(ctx, llvm_usize);
+
+        NDArrayType { ty: llvm_ndarray, dtype, ndims: Some(0), llvm_usize }
+    }
+
+    /// Creates an [`NDArrayType`] from a [unifier type][Type].
+    #[must_use]
+    pub fn from_unifier_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        ty: Type,
+    ) -> Self {
+        let (dtype, ndims) = unpack_ndarray_var_tys(&mut ctx.unifier, ty);
+
+        let llvm_dtype = ctx.get_llvm_type(generator, dtype);
+        let llvm_usize = generator.get_size_type(ctx.ctx);
+        let ndims = extract_ndims(&ctx.unifier, ndims);
+
+        NDArrayType {
+            ty: Self::llvm_type(ctx.ctx, llvm_usize),
+            dtype: llvm_dtype,
+            ndims: Some(ndims),
+            llvm_usize,
+        }
+    }
+
+    /// Creates an [`NDArrayType`] from a [`PointerType`] representing an `NDArray`.
+    #[must_use]
+    pub fn from_type(
+        ptr_ty: PointerType<'ctx>,
+        dtype: BasicTypeEnum<'ctx>,
+        ndims: Option<u64>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Self {
+        debug_assert!(Self::is_representable(ptr_ty, llvm_usize).is_ok());
+
+        NDArrayType { ty: ptr_ty, dtype, ndims, llvm_usize }
+    }
+
+    /// Returns the type of the `size` field of this `ndarray` type.
+    #[must_use]
+    pub fn size_type(&self) -> IntType<'ctx> {
+        self.llvm_usize
+    }
+
+    /// Returns the element type of this `ndarray` type.
+    #[must_use]
+    pub fn element_type(&self) -> BasicTypeEnum<'ctx> {
+        self.dtype
+    }
+
+    /// Returns the number of dimensions of this `ndarray` type.
+    #[must_use]
+    pub fn ndims(&self) -> Option<u64> {
+        self.ndims
+    }
+
+    /// Allocates an instance of [`NDArrayValue`] as if by calling `alloca` on the base type.
+    #[must_use]
+    pub fn alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            self.raw_alloca(generator, ctx, name),
+            self.dtype,
+            self.ndims,
+            self.llvm_usize,
+            name,
+        )
+    }
+
+    /// Allocates an [`NDArrayValue`] on the stack and initializes all fields as follows:
+    ///
+    /// - `data`: uninitialized.
+    /// - `itemsize`: set to the size of `self.dtype`.
+    /// - `ndims`: set to the value of  `ndims`.
+    /// - `shape`: allocated on the stack with an array of length `ndims` with uninitialized values.
+    /// - `strides`: allocated on the stack with an array of length `ndims` with uninitialized
+    ///   values.
+    #[must_use]
+    fn construct_impl<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        ndims: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        let ndarray = self.alloca(generator, ctx, name);
+
+        let itemsize = ctx
+            .builder
+            .build_int_truncate_or_bit_cast(self.dtype.size_of().unwrap(), self.llvm_usize, "")
+            .unwrap();
+        ndarray.store_itemsize(ctx, generator, itemsize);
+
+        ndarray.store_ndims(ctx, generator, ndims);
+
+        ndarray.create_shape(ctx, self.llvm_usize, ndims);
+        ndarray.create_strides(ctx, self.llvm_usize, ndims);
+
+        ndarray
+    }
+
+    /// Allocate an [`NDArrayValue`] on the stack using `dtype` and `ndims` of this [`NDArrayType`]
+    /// instance.
+    ///
+    /// The returned ndarray's content will be:
+    /// - `data`: uninitialized.
+    /// - `itemsize`: set to the size of `dtype`.
+    /// - `ndims`: set to the value of `self.ndims`.
+    /// - `shape`: allocated on the stack with an array of length `ndims` with uninitialized values.
+    /// - `strides`: allocated on the stack with an array of length `ndims` with uninitialized
+    ///   values.
+    #[must_use]
+    pub fn construct_uninitialized<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        assert!(self.ndims.is_some(), "NDArrayType::construct can only be called on an instance with compile-time known ndims (self.ndims = Some(ndims))");
+
+        let Some(ndims) = self.ndims.map(|ndims| self.llvm_usize.const_int(ndims, false)) else {
+            unreachable!()
+        };
+
+        self.construct_impl(generator, ctx, ndims, name)
+    }
+
+    /// Allocate an [`NDArrayValue`] on the stack given its `ndims` and `dtype`.
+    ///
+    /// `shape` and `strides` will be automatically allocated onto the stack.
+    ///
+    /// The returned ndarray's content will be:
+    /// - `data`: uninitialized.
+    /// - `itemsize`: set to the size of `dtype`.
+    /// - `ndims`: set to the value of `ndims`.
+    /// - `shape`: allocated with an array of length `ndims` with uninitialized values.
+    /// - `strides`: allocated with an array of length `ndims` with uninitialized values.
+    #[deprecated = "Prefer construct_uninitialized or construct_*_shape."]
+    #[must_use]
+    pub fn construct_dyn_ndims<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        ndims: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        assert!(self.ndims.is_none(), "NDArrayType::construct_dyn_ndims can only be called on an instance with compile-time unknown ndims (self.ndims = None)");
+
+        self.construct_impl(generator, ctx, ndims, name)
+    }
+
+    /// Convenience function. Allocate an [`NDArrayValue`] with a statically known shape.
+    ///
+    /// The returned [`NDArrayValue`]'s `data` and `strides` are uninitialized.
+    #[must_use]
+    pub fn construct_const_shape<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        shape: &[u64],
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        assert!(self.ndims.is_none_or(|ndims| shape.len() as u64 == ndims));
+
+        let ndarray = Self::new(generator, ctx.ctx, self.dtype, Some(shape.len() as u64))
+            .construct_uninitialized(generator, ctx, name);
+
+        let llvm_usize = generator.get_size_type(ctx.ctx);
+
+        // Write shape
+        let ndarray_shape = ndarray.shape();
+        for (i, dim) in shape.iter().enumerate() {
+            let dim = llvm_usize.const_int(*dim, false);
+            unsafe {
+                ndarray_shape.set_typed_unchecked(
+                    ctx,
+                    generator,
+                    &llvm_usize.const_int(i as u64, false),
+                    dim,
+                );
+            }
+        }
+
+        ndarray
+    }
+
+    /// Convenience function. Allocate an [`NDArrayValue`] with a dynamically known shape.
+    ///
+    /// The returned [`NDArrayValue`]'s `data` and `strides` are uninitialized.
+    #[must_use]
+    pub fn construct_dyn_shape<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        shape: &[IntValue<'ctx>],
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        assert!(self.ndims.is_none_or(|ndims| shape.len() as u64 == ndims));
+
+        let ndarray = Self::new(generator, ctx.ctx, self.dtype, Some(shape.len() as u64))
+            .construct_uninitialized(generator, ctx, name);
+
+        let llvm_usize = generator.get_size_type(ctx.ctx);
+
+        // Write shape
+        let ndarray_shape = ndarray.shape();
+        for (i, dim) in shape.iter().enumerate() {
+            assert_eq!(
+                dim.get_type(),
+                llvm_usize,
+                "Expected {} but got {}",
+                llvm_usize.print_to_string(),
+                dim.get_type().print_to_string()
+            );
+            unsafe {
+                ndarray_shape.set_typed_unchecked(
+                    ctx,
+                    generator,
+                    &llvm_usize.const_int(i as u64, false),
+                    *dim,
+                );
+            }
+        }
+
+        ndarray
+    }
+
+    /// Create an unsized ndarray to contain `value`.
+    #[must_use]
+    pub fn construct_unsized<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        value: &impl BasicValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> NDArrayValue<'ctx> {
+        let value = value.as_basic_value_enum();
+
+        assert_eq!(value.get_type(), self.dtype);
+        assert!(self.ndims.is_none_or(|ndims| ndims == 0));
+
+        // We have to put the value on the stack to get a data pointer.
+        let data = ctx.builder.build_alloca(value.get_type(), "construct_unsized").unwrap();
+        ctx.builder.build_store(data, value).unwrap();
+        let data = ctx
+            .builder
+            .build_pointer_cast(data, ctx.ctx.i8_type().ptr_type(AddressSpace::default()), "")
+            .unwrap();
+
+        let ndarray = Self::new_unsized(generator, ctx.ctx, value.get_type())
+            .construct_uninitialized(generator, ctx, name);
+        ctx.builder.build_store(ndarray.ptr_to_data(ctx), data).unwrap();
+        ndarray
+    }
+
+    /// Converts an existing value into a [`NDArrayValue`].
+    #[must_use]
+    pub fn map_value(
+        &self,
+        value: <<Self as ProxyType<'ctx>>::Value as ProxyValue<'ctx>>::Base,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            value,
+            self.dtype,
+            self.ndims,
+            self.llvm_usize,
+            name,
+        )
+    }
+}
+
+impl<'ctx> ProxyType<'ctx> for NDArrayType<'ctx> {
+    type Base = PointerType<'ctx>;
+    type Value = NDArrayValue<'ctx>;
+
+    fn is_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: impl BasicType<'ctx>,
+    ) -> Result<(), String> {
+        if let BasicTypeEnum::PointerType(ty) = llvm_ty.as_basic_type_enum() {
+            <Self as ProxyType<'ctx>>::is_representable(generator, ctx, ty)
+        } else {
+            Err(format!("Expected pointer type, got {llvm_ty:?}"))
+        }
+    }
+
+    fn is_representable<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: Self::Base,
+    ) -> Result<(), String> {
+        Self::is_representable(llvm_ty, generator.get_size_type(ctx))
+    }
+
+    fn raw_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self::Value as ProxyValue<'ctx>>::Base {
+        generator
+            .gen_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                name,
+            )
+            .unwrap()
+    }
+
+    fn array_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        size: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> ArraySliceValue<'ctx> {
+        generator
+            .gen_array_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                size,
+                name,
+            )
+            .unwrap()
+    }
+
+    fn as_base_type(&self) -> Self::Base {
+        self.ty
+    }
+}
+
+impl<'ctx> From<NDArrayType<'ctx>> for PointerType<'ctx> {
+    fn from(value: NDArrayType<'ctx>) -> Self {
+        value.as_base_type()
+    }
+}

nac3core/src/codegen/types/ndarray/nditer.rs

@@ -0,0 +1,241 @@
+use inkwell::{
+    context::{AsContextRef, Context},
+    types::{AnyTypeEnum, BasicType, BasicTypeEnum, IntType, PointerType},
+    values::{IntValue, PointerValue},
+    AddressSpace,
+};
+use itertools::Itertools;
+
+use nac3core_derive::StructFields;
+
+use super::ProxyType;
+use crate::codegen::{
+    irrt,
+    types::structure::{check_struct_type_matches_fields, StructField, StructFields},
+    values::{
+        ndarray::{NDArrayValue, NDIterValue},
+        ArraySliceValue, ProxyValue,
+    },
+    CodeGenContext, CodeGenerator,
+};
+
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub struct NDIterType<'ctx> {
+    ty: PointerType<'ctx>,
+    llvm_usize: IntType<'ctx>,
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct NDIterStructFields<'ctx> {
+    #[value_type(usize)]
+    pub ndims: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(usize.ptr_type(AddressSpace::default()))]
+    pub shape: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(usize.ptr_type(AddressSpace::default()))]
+    pub strides: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(usize.ptr_type(AddressSpace::default()))]
+    pub indices: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(usize)]
+    pub nth: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(i8_type().ptr_type(AddressSpace::default()))]
+    pub element: StructField<'ctx, PointerValue<'ctx>>,
+    #[value_type(usize)]
+    pub size: StructField<'ctx, IntValue<'ctx>>,
+}
+
+impl<'ctx> NDIterType<'ctx> {
+    /// Checks whether `llvm_ty` represents a `nditer` type, returning [Err] if it does not.
+    pub fn is_representable(
+        llvm_ty: PointerType<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        let ctx = llvm_ty.get_context();
+
+        let llvm_ty = llvm_ty.get_element_type();
+        let AnyTypeEnum::StructType(llvm_ndarray_ty) = llvm_ty else {
+            return Err(format!("Expected struct type for `NDIter` type, got {llvm_ty}"));
+        };
+
+        check_struct_type_matches_fields(
+            Self::fields(ctx, llvm_usize),
+            llvm_ndarray_ty,
+            "NDIter",
+            &[],
+        )
+    }
+
+    /// Returns an instance of [`StructFields`] containing all field accessors for this type.
+    #[must_use]
+    fn fields(ctx: impl AsContextRef<'ctx>, llvm_usize: IntType<'ctx>) -> NDIterStructFields<'ctx> {
+        NDIterStructFields::new(ctx, llvm_usize)
+    }
+
+    /// See [`NDIterType::fields`].
+    // TODO: Move this into e.g. StructProxyType
+    #[must_use]
+    pub fn get_fields(&self, ctx: impl AsContextRef<'ctx>) -> NDIterStructFields<'ctx> {
+        Self::fields(ctx, self.llvm_usize)
+    }
+
+    /// Creates an LLVM type corresponding to the expected structure of an `NDIter`.
+    #[must_use]
+    fn llvm_type(ctx: &'ctx Context, llvm_usize: IntType<'ctx>) -> PointerType<'ctx> {
+        let field_tys =
+            Self::fields(ctx, llvm_usize).into_iter().map(|field| field.1).collect_vec();
+
+        ctx.struct_type(&field_tys, false).ptr_type(AddressSpace::default())
+    }
+
+    /// Creates an instance of [`NDIter`].
+    #[must_use]
+    pub fn new<G: CodeGenerator + ?Sized>(generator: &G, ctx: &'ctx Context) -> Self {
+        let llvm_usize = generator.get_size_type(ctx);
+        let llvm_nditer = Self::llvm_type(ctx, llvm_usize);
+
+        Self { ty: llvm_nditer, llvm_usize }
+    }
+
+    /// Creates an [`NDIterType`] from a [`PointerType`] representing an `NDIter`.
+    #[must_use]
+    pub fn from_type(ptr_ty: PointerType<'ctx>, llvm_usize: IntType<'ctx>) -> Self {
+        debug_assert!(Self::is_representable(ptr_ty, llvm_usize).is_ok());
+
+        Self { ty: ptr_ty, llvm_usize }
+    }
+
+    /// Returns the type of the `size` field of this `nditer` type.
+    #[must_use]
+    pub fn size_type(&self) -> IntType<'ctx> {
+        self.llvm_usize
+    }
+
+    #[must_use]
+    pub fn alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        parent: NDArrayValue<'ctx>,
+        indices: ArraySliceValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            self.raw_alloca(generator, ctx, name),
+            parent,
+            indices,
+            self.llvm_usize,
+            name,
+        )
+    }
+
+    /// Allocate an [`NDIter`] that iterates through the given `ndarray`.
+    #[must_use]
+    pub fn construct<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        ndarray: NDArrayValue<'ctx>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        let nditer = self.raw_alloca(generator, ctx, None);
+        let ndims = ndarray.load_ndims(ctx);
+
+        // The caller has the responsibility to allocate 'indices' for `NDIter`.
+        let indices =
+            generator.gen_array_var_alloc(ctx, self.llvm_usize.into(), ndims, None).unwrap();
+
+        let nditer = <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            nditer,
+            ndarray,
+            indices,
+            self.llvm_usize,
+            None,
+        );
+
+        irrt::ndarray::call_nac3_nditer_initialize(generator, ctx, nditer, ndarray, indices);
+
+        nditer
+    }
+
+    #[must_use]
+    pub fn map_value(
+        &self,
+        value: <<Self as ProxyType<'ctx>>::Value as ProxyValue<'ctx>>::Base,
+        parent: NDArrayValue<'ctx>,
+        indices: ArraySliceValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            value,
+            parent,
+            indices,
+            self.llvm_usize,
+            name,
+        )
+    }
+}
+
+impl<'ctx> ProxyType<'ctx> for NDIterType<'ctx> {
+    type Base = PointerType<'ctx>;
+    type Value = NDIterValue<'ctx>;
+
+    fn is_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: impl BasicType<'ctx>,
+    ) -> Result<(), String> {
+        if let BasicTypeEnum::PointerType(ty) = llvm_ty.as_basic_type_enum() {
+            <Self as ProxyType<'ctx>>::is_representable(generator, ctx, ty)
+        } else {
+            Err(format!("Expected pointer type, got {llvm_ty:?}"))
+        }
+    }
+
+    fn is_representable<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: Self::Base,
+    ) -> Result<(), String> {
+        Self::is_representable(llvm_ty, generator.get_size_type(ctx))
+    }
+
+    fn raw_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self::Value as ProxyValue<'ctx>>::Base {
+        generator
+            .gen_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                name,
+            )
+            .unwrap()
+    }
+
+    fn array_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        size: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> ArraySliceValue<'ctx> {
+        generator
+            .gen_array_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                size,
+                name,
+            )
+            .unwrap()
+    }
+
+    fn as_base_type(&self) -> Self::Base {
+        self.ty
+    }
+}
+
+impl<'ctx> From<NDIterType<'ctx>> for PointerType<'ctx> {
+    fn from(value: NDIterType<'ctx>) -> Self {
+        value.as_base_type()
+    }
+}

nac3core/src/codegen/types/range.rs

@@ -0,0 +1,170 @@
+use inkwell::{
+    context::Context,
+    types::{AnyTypeEnum, BasicType, BasicTypeEnum, IntType, PointerType},
+    values::IntValue,
+    AddressSpace,
+};
+
+use super::ProxyType;
+use crate::codegen::{
+    values::{ArraySliceValue, ProxyValue, RangeValue},
+    {CodeGenContext, CodeGenerator},
+};
+
+/// Proxy type for a `range` type in LLVM.
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub struct RangeType<'ctx> {
+    ty: PointerType<'ctx>,
+}
+
+impl<'ctx> RangeType<'ctx> {
+    /// Checks whether `llvm_ty` represents a `range` type, returning [Err] if it does not.
+    pub fn is_representable(llvm_ty: PointerType<'ctx>) -> Result<(), String> {
+        let llvm_range_ty = llvm_ty.get_element_type();
+        let AnyTypeEnum::ArrayType(llvm_range_ty) = llvm_range_ty else {
+            return Err(format!("Expected array type for `range` type, got {llvm_range_ty}"));
+        };
+        if llvm_range_ty.len() != 3 {
+            return Err(format!(
+                "Expected 3 elements for `range` type, got {}",
+                llvm_range_ty.len()
+            ));
+        }
+
+        let llvm_range_elem_ty = llvm_range_ty.get_element_type();
+        let Ok(llvm_range_elem_ty) = IntType::try_from(llvm_range_elem_ty) else {
+            return Err(format!(
+                "Expected int type for `range` element type, got {llvm_range_elem_ty}"
+            ));
+        };
+        if llvm_range_elem_ty.get_bit_width() != 32 {
+            return Err(format!(
+                "Expected 32-bit int type for `range` element type, got {}",
+                llvm_range_elem_ty.get_bit_width()
+            ));
+        }
+
+        Ok(())
+    }
+
+    /// Creates an LLVM type corresponding to the expected structure of a `Range`.
+    #[must_use]
+    fn llvm_type(ctx: &'ctx Context) -> PointerType<'ctx> {
+        // typedef int32_t Range[3];
+        let llvm_i32 = ctx.i32_type();
+        llvm_i32.array_type(3).ptr_type(AddressSpace::default())
+    }
+
+    /// Creates an instance of [`RangeType`].
+    #[must_use]
+    pub fn new(ctx: &'ctx Context) -> Self {
+        let llvm_range = Self::llvm_type(ctx);
+
+        RangeType::from_type(llvm_range)
+    }
+
+    /// Creates an [`RangeType`] from a [`PointerType`].
+    #[must_use]
+    pub fn from_type(ptr_ty: PointerType<'ctx>) -> Self {
+        debug_assert!(Self::is_representable(ptr_ty).is_ok());
+
+        RangeType { ty: ptr_ty }
+    }
+
+    /// Returns the type of all fields of this `range` type.
+    #[must_use]
+    pub fn value_type(&self) -> IntType<'ctx> {
+        self.as_base_type().get_element_type().into_array_type().get_element_type().into_int_type()
+    }
+
+    /// Allocates an instance of [`RangeValue`] as if by calling `alloca` on the base type.
+    #[must_use]
+    pub fn alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            self.raw_alloca(generator, ctx, name),
+            name,
+        )
+    }
+
+    /// Converts an existing value into a [`RangeValue`].
+    #[must_use]
+    pub fn map_value(
+        &self,
+        value: <<Self as ProxyType<'ctx>>::Value as ProxyValue<'ctx>>::Base,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(value, name)
+    }
+}
+
+impl<'ctx> ProxyType<'ctx> for RangeType<'ctx> {
+    type Base = PointerType<'ctx>;
+    type Value = RangeValue<'ctx>;
+
+    fn is_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: impl BasicType<'ctx>,
+    ) -> Result<(), String> {
+        if let BasicTypeEnum::PointerType(ty) = llvm_ty.as_basic_type_enum() {
+            <Self as ProxyType<'ctx>>::is_representable(generator, ctx, ty)
+        } else {
+            Err(format!("Expected pointer type, got {llvm_ty:?}"))
+        }
+    }
+
+    fn is_representable<G: CodeGenerator + ?Sized>(
+        _: &G,
+        _: &'ctx Context,
+        llvm_ty: Self::Base,
+    ) -> Result<(), String> {
+        Self::is_representable(llvm_ty)
+    }
+
+    fn raw_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self::Value as ProxyValue<'ctx>>::Base {
+        generator
+            .gen_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                name,
+            )
+            .unwrap()
+    }
+
+    fn array_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        size: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> ArraySliceValue<'ctx> {
+        generator
+            .gen_array_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                size,
+                name,
+            )
+            .unwrap()
+    }
+
+    fn as_base_type(&self) -> Self::Base {
+        self.ty
+    }
+}
+
+impl<'ctx> From<RangeType<'ctx>> for PointerType<'ctx> {
+    fn from(value: RangeType<'ctx>) -> Self {
+        value.as_base_type()
+    }
+}

nac3core/src/codegen/types/structure.rs

@@ -0,0 +1,255 @@
+use std::marker::PhantomData;
+
+use inkwell::{
+    context::AsContextRef,
+    types::{BasicTypeEnum, IntType, StructType},
+    values::{BasicValue, BasicValueEnum, IntValue, PointerValue, StructValue},
+};
+
+use crate::codegen::CodeGenContext;
+
+/// Trait indicating that the structure is a field-wise representation of an LLVM structure.
+///
+/// # Usage
+///
+/// For example, for a simple C-slice LLVM structure:
+///
+/// ```ignore
+/// struct CSliceFields<'ctx> {
+///     ptr: StructField<'ctx, PointerValue<'ctx>>,
+///     len: StructField<'ctx, IntValue<'ctx>>
+/// }
+/// ```
+pub trait StructFields<'ctx>: Eq + Copy {
+    /// Creates an instance of [`StructFields`] using the given `ctx` and `size_t` types.
+    fn new(ctx: impl AsContextRef<'ctx>, llvm_usize: IntType<'ctx>) -> Self;
+
+    /// Returns a [`Vec`] that contains the fields of the structure in the order as they appear in
+    /// the type definition.
+    #[must_use]
+    fn to_vec(&self) -> Vec<(&'static str, BasicTypeEnum<'ctx>)>;
+
+    /// Returns a [`Iterator`] that contains the fields of the structure in the order as they appear
+    /// in the type definition.
+    #[must_use]
+    fn iter(&self) -> impl Iterator<Item = (&'static str, BasicTypeEnum<'ctx>)> {
+        self.to_vec().into_iter()
+    }
+
+    /// Returns a [`Vec`] that contains the fields of the structure in the order as they appear in
+    /// the type definition.
+    #[must_use]
+    fn into_vec(self) -> Vec<(&'static str, BasicTypeEnum<'ctx>)>
+    where
+        Self: Sized,
+    {
+        self.to_vec()
+    }
+
+    /// Returns a [`Iterator`] that contains the fields of the structure in the order as they appear
+    /// in the type definition.
+    #[must_use]
+    fn into_iter(self) -> impl Iterator<Item = (&'static str, BasicTypeEnum<'ctx>)>
+    where
+        Self: Sized,
+    {
+        self.into_vec().into_iter()
+    }
+}
+
+/// A single field of an LLVM structure.
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub struct StructField<'ctx, Value>
+where
+    Value: BasicValue<'ctx> + TryFrom<BasicValueEnum<'ctx>, Error = ()>,
+{
+    /// The index of this field within the structure.
+    index: u32,
+
+    /// The name of this field.
+    name: &'static str,
+
+    /// The type of this field.
+    ty: BasicTypeEnum<'ctx>,
+
+    /// Instance of [`PhantomData`] containing [`Value`], used to implement automatic downcasts.
+    _value_ty: PhantomData<Value>,
+}
+
+impl<'ctx, Value> StructField<'ctx, Value>
+where
+    Value: BasicValue<'ctx> + TryFrom<BasicValueEnum<'ctx>, Error = ()>,
+{
+    /// Creates an instance of [`StructField`].
+    ///
+    /// * `idx_counter` - The instance of [`FieldIndexCounter`] used to track the current field
+    ///   index.
+    /// * `name` - Name of the field.
+    /// * `ty` - The type of this field.
+    pub fn create(
+        idx_counter: &mut FieldIndexCounter,
+        name: &'static str,
+        ty: impl Into<BasicTypeEnum<'ctx>>,
+    ) -> Self {
+        StructField { index: idx_counter.increment(), name, ty: ty.into(), _value_ty: PhantomData }
+    }
+
+    /// Creates an instance of [`StructField`] with a given index.
+    ///
+    /// * `index` - The index of this field within its enclosing structure.
+    /// * `name` - Name of the field.
+    /// * `ty` - The type of this field.
+    pub fn create_at(index: u32, name: &'static str, ty: impl Into<BasicTypeEnum<'ctx>>) -> Self {
+        StructField { index, name, ty: ty.into(), _value_ty: PhantomData }
+    }
+
+    /// Returns the name of this field.
+    #[must_use]
+    pub fn name(&self) -> &'static str {
+        self.name
+    }
+
+    /// Creates a pointer to this field in an arbitrary structure by performing a `getelementptr i32
+    /// {idx...}, i32 {self.index}`.
+    pub fn ptr_by_array_gep(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        pobj: PointerValue<'ctx>,
+        idx: &[IntValue<'ctx>],
+    ) -> PointerValue<'ctx> {
+        unsafe {
+            ctx.builder.build_in_bounds_gep(
+                pobj,
+                &[idx, &[ctx.ctx.i32_type().const_int(u64::from(self.index), false)]].concat(),
+                "",
+            )
+        }
+        .unwrap()
+    }
+
+    /// Creates a pointer to this field in an arbitrary structure by performing the equivalent of
+    /// `getelementptr i32 0, i32 {self.index}`.
+    pub fn ptr_by_gep(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        pobj: PointerValue<'ctx>,
+        obj_name: Option<&'ctx str>,
+    ) -> PointerValue<'ctx> {
+        ctx.builder
+            .build_struct_gep(
+                pobj,
+                self.index,
+                &obj_name.map(|name| format!("{name}.{}.addr", self.name)).unwrap_or_default(),
+            )
+            .unwrap()
+    }
+
+    /// Gets the value of this field for a given `obj`.
+    #[must_use]
+    pub fn get_from_value(&self, obj: StructValue<'ctx>) -> Value {
+        obj.get_field_at_index(self.index).and_then(|value| Value::try_from(value).ok()).unwrap()
+    }
+
+    /// Sets the value of this field for a given `obj`.
+    pub fn set_for_value(&self, obj: StructValue<'ctx>, value: Value) {
+        obj.set_field_at_index(self.index, value);
+    }
+
+    /// Gets the value of this field for a pointer-to-structure.
+    pub fn get(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        pobj: PointerValue<'ctx>,
+        obj_name: Option<&'ctx str>,
+    ) -> Value {
+        ctx.builder
+            .build_load(
+                self.ptr_by_gep(ctx, pobj, obj_name),
+                &obj_name.map(|name| format!("{name}.{}", self.name)).unwrap_or_default(),
+            )
+            .map_err(|_| ())
+            .and_then(|value| Value::try_from(value))
+            .unwrap()
+    }
+
+    /// Sets the value of this field for a pointer-to-structure.
+    pub fn set(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        pobj: PointerValue<'ctx>,
+        value: Value,
+        obj_name: Option<&'ctx str>,
+    ) {
+        ctx.builder.build_store(self.ptr_by_gep(ctx, pobj, obj_name), value).unwrap();
+    }
+}
+
+impl<'ctx, Value> From<StructField<'ctx, Value>> for (&'static str, BasicTypeEnum<'ctx>)
+where
+    Value: BasicValue<'ctx> + TryFrom<BasicValueEnum<'ctx>, Error = ()>,
+{
+    fn from(value: StructField<'ctx, Value>) -> Self {
+        (value.name, value.ty)
+    }
+}
+
+/// A counter that tracks the next index of a field using a monotonically increasing counter.
+#[derive(Default, Debug, PartialEq, Eq, Clone, Copy)]
+pub struct FieldIndexCounter(u32);
+
+impl FieldIndexCounter {
+    /// Increments the number stored by this counter, returning the previous value.
+    ///
+    /// Functionally equivalent to `i++` in C-based languages.
+    pub fn increment(&mut self) -> u32 {
+        let v = self.0;
+        self.0 += 1;
+        v
+    }
+}
+
+type FieldTypeVerifier<'ctx> = dyn Fn(BasicTypeEnum<'ctx>) -> Result<(), String>;
+
+/// Checks whether [`llvm_ty`][StructType] contains the fields described by the given
+/// [`StructFields`] instance.
+///
+/// By default, this function will compare the type of each field in `expected_fields` against
+/// `llvm_ty`. To override this behavior for individual fields, pass in overrides to
+/// `custom_verifiers`, which will use the specified verifier when a field with the matching field
+/// name is being checked.
+pub(super) fn check_struct_type_matches_fields<'ctx>(
+    expected_fields: impl StructFields<'ctx>,
+    llvm_ty: StructType<'ctx>,
+    ty_name: &'static str,
+    custom_verifiers: &[(&str, &FieldTypeVerifier<'ctx>)],
+) -> Result<(), String> {
+    let expected_fields = expected_fields.to_vec();
+
+    if llvm_ty.count_fields() != u32::try_from(expected_fields.len()).unwrap() {
+        return Err(format!(
+            "Expected {} fields in `{ty_name}`, got {}",
+            expected_fields.len(),
+            llvm_ty.count_fields(),
+        ));
+    }
+
+    expected_fields
+        .into_iter()
+        .enumerate()
+        .map(|(i, (field_name, expected_ty))| {
+            (field_name, expected_ty, llvm_ty.get_field_type_at_index(i as u32).unwrap())
+        })
+        .try_for_each(|(field_name, expected_ty, actual_ty)| {
+            if let Some((_, verifier)) =
+                custom_verifiers.iter().find(|verifier| verifier.0 == field_name)
+            {
+                verifier(actual_ty)
+            } else if expected_ty == actual_ty {
+                Ok(())
+            } else {
+                Err(format!("Expected {expected_ty} for `{ty_name}.{field_name}`, got {actual_ty}"))
+            }
+        })?;
+
+    Ok(())
+}

nac3core/src/codegen/types/utils/mod.rs

@@ -0,0 +1,3 @@
+pub use slice::*;
+
+mod slice;

nac3core/src/codegen/types/utils/slice.rs

@@ -0,0 +1,254 @@
+use inkwell::{
+    context::{AsContextRef, Context, ContextRef},
+    types::{AnyTypeEnum, BasicType, BasicTypeEnum, IntType, PointerType},
+    values::IntValue,
+    AddressSpace,
+};
+use itertools::Itertools;
+
+use nac3core_derive::StructFields;
+
+use crate::codegen::{
+    types::{
+        structure::{
+            check_struct_type_matches_fields, FieldIndexCounter, StructField, StructFields,
+        },
+        ProxyType,
+    },
+    values::{utils::SliceValue, ArraySliceValue, ProxyValue},
+    CodeGenContext, CodeGenerator,
+};
+
+#[derive(Debug, PartialEq, Eq, Clone, Copy)]
+pub struct SliceType<'ctx> {
+    ty: PointerType<'ctx>,
+    int_ty: IntType<'ctx>,
+    llvm_usize: IntType<'ctx>,
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, StructFields)]
+pub struct SliceFields<'ctx> {
+    #[value_type(bool_type())]
+    pub start_defined: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(usize)]
+    pub start: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(bool_type())]
+    pub stop_defined: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(usize)]
+    pub stop: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(bool_type())]
+    pub step_defined: StructField<'ctx, IntValue<'ctx>>,
+    #[value_type(usize)]
+    pub step: StructField<'ctx, IntValue<'ctx>>,
+}
+
+impl<'ctx> SliceFields<'ctx> {
+    /// Creates a new instance of [`SliceFields`] with a custom integer type for its range values.
+    #[must_use]
+    pub fn new_sized(ctx: &impl AsContextRef<'ctx>, int_ty: IntType<'ctx>) -> Self {
+        let ctx = unsafe { ContextRef::new(ctx.as_ctx_ref()) };
+        let mut counter = FieldIndexCounter::default();
+
+        SliceFields {
+            start_defined: StructField::create(&mut counter, "start_defined", ctx.bool_type()),
+            start: StructField::create(&mut counter, "start", int_ty),
+            stop_defined: StructField::create(&mut counter, "stop_defined", ctx.bool_type()),
+            stop: StructField::create(&mut counter, "stop", int_ty),
+            step_defined: StructField::create(&mut counter, "step_defined", ctx.bool_type()),
+            step: StructField::create(&mut counter, "step", int_ty),
+        }
+    }
+}
+
+impl<'ctx> SliceType<'ctx> {
+    /// Checks whether `llvm_ty` represents a `slice` type, returning [Err] if it does not.
+    pub fn is_representable(
+        llvm_ty: PointerType<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        let ctx = llvm_ty.get_context();
+
+        let fields = SliceFields::new(ctx, llvm_usize);
+
+        let llvm_ty = llvm_ty.get_element_type();
+        let AnyTypeEnum::StructType(llvm_ty) = llvm_ty else {
+            return Err(format!("Expected struct type for `Slice` type, got {llvm_ty}"));
+        };
+
+        check_struct_type_matches_fields(
+            fields,
+            llvm_ty,
+            "Slice",
+            &[
+                (fields.start.name(), &|ty| {
+                    if ty.is_int_type() {
+                        Ok(())
+                    } else {
+                        Err(format!("Expected int type for `Slice.start`, got {ty}"))
+                    }
+                }),
+                (fields.stop.name(), &|ty| {
+                    if ty.is_int_type() {
+                        Ok(())
+                    } else {
+                        Err(format!("Expected int type for `Slice.stop`, got {ty}"))
+                    }
+                }),
+                (fields.step.name(), &|ty| {
+                    if ty.is_int_type() {
+                        Ok(())
+                    } else {
+                        Err(format!("Expected int type for `Slice.step`, got {ty}"))
+                    }
+                }),
+            ],
+        )
+    }
+
+    // TODO: Move this into e.g. StructProxyType
+    #[must_use]
+    pub fn get_fields(&self) -> SliceFields<'ctx> {
+        SliceFields::new_sized(&self.int_ty.get_context(), self.int_ty)
+    }
+
+    /// Creates an LLVM type corresponding to the expected structure of a `Slice`.
+    #[must_use]
+    fn llvm_type(ctx: &'ctx Context, int_ty: IntType<'ctx>) -> PointerType<'ctx> {
+        let field_tys = SliceFields::new_sized(&int_ty.get_context(), int_ty)
+            .into_iter()
+            .map(|field| field.1)
+            .collect_vec();
+
+        ctx.struct_type(&field_tys, false).ptr_type(AddressSpace::default())
+    }
+
+    /// Creates an instance of [`SliceType`] with `int_ty` as its backing integer type.
+    #[must_use]
+    pub fn new(ctx: &'ctx Context, int_ty: IntType<'ctx>, llvm_usize: IntType<'ctx>) -> Self {
+        let llvm_ty = Self::llvm_type(ctx, int_ty);
+
+        Self { ty: llvm_ty, int_ty, llvm_usize }
+    }
+
+    /// Creates an instance of [`SliceType`] with `usize` as its backing integer type.
+    #[must_use]
+    pub fn new_usize<G: CodeGenerator + ?Sized>(generator: &G, ctx: &'ctx Context) -> Self {
+        let llvm_usize = generator.get_size_type(ctx);
+        Self::new(ctx, llvm_usize, llvm_usize)
+    }
+
+    /// Creates an [`SliceType`] from a [`PointerType`] representing a `slice`.
+    #[must_use]
+    pub fn from_type(
+        ptr_ty: PointerType<'ctx>,
+        int_ty: IntType<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Self {
+        debug_assert!(Self::is_representable(ptr_ty, int_ty).is_ok());
+
+        Self { ty: ptr_ty, int_ty, llvm_usize }
+    }
+
+    #[must_use]
+    pub fn element_type(&self) -> IntType<'ctx> {
+        self.int_ty
+    }
+
+    /// Allocates an instance of [`ContiguousNDArrayValue`] as if by calling `alloca` on the base type.
+    #[must_use]
+    pub fn alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            self.raw_alloca(generator, ctx, name),
+            self.int_ty,
+            self.llvm_usize,
+            name,
+        )
+    }
+
+    /// Converts an existing value into a [`ContiguousNDArrayValue`].
+    #[must_use]
+    pub fn map_value(
+        &self,
+        value: <<Self as ProxyType<'ctx>>::Value as ProxyValue<'ctx>>::Base,
+        name: Option<&'ctx str>,
+    ) -> <Self as ProxyType<'ctx>>::Value {
+        <Self as ProxyType<'ctx>>::Value::from_pointer_value(
+            value,
+            self.int_ty,
+            self.llvm_usize,
+            name,
+        )
+    }
+}
+
+impl<'ctx> ProxyType<'ctx> for SliceType<'ctx> {
+    type Base = PointerType<'ctx>;
+    type Value = SliceValue<'ctx>;
+
+    fn is_type<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: impl BasicType<'ctx>,
+    ) -> Result<(), String> {
+        if let BasicTypeEnum::PointerType(ty) = llvm_ty.as_basic_type_enum() {
+            <Self as ProxyType<'ctx>>::is_representable(generator, ctx, ty)
+        } else {
+            Err(format!("Expected pointer type, got {llvm_ty:?}"))
+        }
+    }
+
+    fn is_representable<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        llvm_ty: Self::Base,
+    ) -> Result<(), String> {
+        Self::is_representable(llvm_ty, generator.get_size_type(ctx))
+    }
+
+    fn raw_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&'ctx str>,
+    ) -> <Self::Value as ProxyValue<'ctx>>::Base {
+        generator
+            .gen_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                name,
+            )
+            .unwrap()
+    }
+
+    fn array_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        size: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> ArraySliceValue<'ctx> {
+        generator
+            .gen_array_var_alloc(
+                ctx,
+                self.as_base_type().get_element_type().into_struct_type().into(),
+                size,
+                name,
+            )
+            .unwrap()
+    }
+
+    fn as_base_type(&self) -> Self::Base {
+        self.ty
+    }
+}
+
+impl<'ctx> From<SliceType<'ctx>> for PointerType<'ctx> {
+    fn from(value: SliceType<'ctx>) -> Self {
+        value.as_base_type()
+    }
+}

nac3core/src/codegen/values/array.rs

@@ -0,0 +1,426 @@
+use inkwell::{
+    types::AnyTypeEnum,
+    values::{BasicValueEnum, IntValue, PointerValue},
+    IntPredicate,
+};
+
+use crate::codegen::{CodeGenContext, CodeGenerator};
+
+/// An LLVM value that is array-like, i.e. it contains a contiguous, sequenced collection of
+/// elements.
+pub trait ArrayLikeValue<'ctx> {
+    /// Returns the element type of this array-like value.
+    fn element_type<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> AnyTypeEnum<'ctx>;
+
+    /// Returns the base pointer to the array.
+    fn base_ptr<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> PointerValue<'ctx>;
+
+    /// Returns the size of this array-like value.
+    fn size<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> IntValue<'ctx>;
+
+    /// Returns a [`ArraySliceValue`] representing this value.
+    fn as_slice_value<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> ArraySliceValue<'ctx> {
+        ArraySliceValue::from_ptr_val(
+            self.base_ptr(ctx, generator),
+            self.size(ctx, generator),
+            None,
+        )
+    }
+}
+
+/// An array-like value that can be indexed by memory offset.
+pub trait ArrayLikeIndexer<'ctx, Index = IntValue<'ctx>>: ArrayLikeValue<'ctx> {
+    /// # Safety
+    ///
+    /// This function should be called with a valid index.
+    unsafe fn ptr_offset_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx>;
+
+    /// Returns the pointer to the data at the `idx`-th index.
+    fn ptr_offset<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx>;
+}
+
+/// An array-like value that can have its array elements accessed as a [`BasicValueEnum`].
+pub trait UntypedArrayLikeAccessor<'ctx, Index = IntValue<'ctx>>:
+    ArrayLikeIndexer<'ctx, Index>
+{
+    /// # Safety
+    ///
+    /// This function should be called with a valid index.
+    unsafe fn get_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        name: Option<&str>,
+    ) -> BasicValueEnum<'ctx> {
+        let ptr = unsafe { self.ptr_offset_unchecked(ctx, generator, idx, name) };
+        ctx.builder.build_load(ptr, name.unwrap_or_default()).unwrap()
+    }
+
+    /// Returns the data at the `idx`-th index.
+    fn get<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        name: Option<&str>,
+    ) -> BasicValueEnum<'ctx> {
+        let ptr = self.ptr_offset(ctx, generator, idx, name);
+        ctx.builder.build_load(ptr, name.unwrap_or_default()).unwrap()
+    }
+}
+
+/// An array-like value that can have its array elements mutated as a [`BasicValueEnum`].
+pub trait UntypedArrayLikeMutator<'ctx, Index = IntValue<'ctx>>:
+    ArrayLikeIndexer<'ctx, Index>
+{
+    /// # Safety
+    ///
+    /// This function should be called with a valid index.
+    unsafe fn set_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        value: BasicValueEnum<'ctx>,
+    ) {
+        let ptr = unsafe { self.ptr_offset_unchecked(ctx, generator, idx, None) };
+        ctx.builder.build_store(ptr, value).unwrap();
+    }
+
+    /// Sets the data at the `idx`-th index.
+    fn set<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        value: BasicValueEnum<'ctx>,
+    ) {
+        let ptr = self.ptr_offset(ctx, generator, idx, None);
+        ctx.builder.build_store(ptr, value).unwrap();
+    }
+}
+
+/// An array-like value that can have its array elements accessed as an arbitrary type `T`.
+pub trait TypedArrayLikeAccessor<'ctx, T, Index = IntValue<'ctx>>:
+    UntypedArrayLikeAccessor<'ctx, Index>
+{
+    /// Casts an element from [`BasicValueEnum`] into `T`.
+    fn downcast_to_type(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        value: BasicValueEnum<'ctx>,
+    ) -> T;
+
+    /// # Safety
+    ///
+    /// This function should be called with a valid index.
+    unsafe fn get_typed_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        name: Option<&str>,
+    ) -> T {
+        let value = unsafe { self.get_unchecked(ctx, generator, idx, name) };
+        self.downcast_to_type(ctx, value)
+    }
+
+    /// Returns the data at the `idx`-th index.
+    fn get_typed<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        name: Option<&str>,
+    ) -> T {
+        let value = self.get(ctx, generator, idx, name);
+        self.downcast_to_type(ctx, value)
+    }
+}
+
+/// An array-like value that can have its array elements mutated as an arbitrary type `T`.
+pub trait TypedArrayLikeMutator<'ctx, T, Index = IntValue<'ctx>>:
+    UntypedArrayLikeMutator<'ctx, Index>
+{
+    /// Casts an element from T into [`BasicValueEnum`].
+    fn upcast_from_type(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        value: T,
+    ) -> BasicValueEnum<'ctx>;
+
+    /// # Safety
+    ///
+    /// This function should be called with a valid index.
+    unsafe fn set_typed_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        value: T,
+    ) {
+        let value = self.upcast_from_type(ctx, value);
+        unsafe { self.set_unchecked(ctx, generator, idx, value) }
+    }
+
+    /// Sets the data at the `idx`-th index.
+    fn set_typed<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        value: T,
+    ) {
+        let value = self.upcast_from_type(ctx, value);
+        self.set(ctx, generator, idx, value);
+    }
+}
+
+/// Type alias for a function that casts a [`BasicValueEnum`] into a `T`.
+type ValueDowncastFn<'ctx, T> =
+    Box<dyn Fn(&mut CodeGenContext<'ctx, '_>, BasicValueEnum<'ctx>) -> T + 'ctx>;
+/// Type alias for a function that casts a `T` into a [`BasicValueEnum`].
+type ValueUpcastFn<'ctx, T> = Box<dyn Fn(&mut CodeGenContext<'ctx, '_>, T) -> BasicValueEnum<'ctx>>;
+
+/// An adapter for constraining untyped array values as typed values.
+pub struct TypedArrayLikeAdapter<'ctx, T, Adapted: ArrayLikeValue<'ctx> = ArraySliceValue<'ctx>> {
+    adapted: Adapted,
+    downcast_fn: ValueDowncastFn<'ctx, T>,
+    upcast_fn: ValueUpcastFn<'ctx, T>,
+}
+
+impl<'ctx, T, Adapted> TypedArrayLikeAdapter<'ctx, T, Adapted>
+where
+    Adapted: ArrayLikeValue<'ctx>,
+{
+    /// Creates a [`TypedArrayLikeAdapter`].
+    ///
+    /// * `adapted` - The value to be adapted.
+    /// * `downcast_fn` - The function converting a [`BasicValueEnum`] into a `T`.
+    /// * `upcast_fn` - The function converting a T into a [`BasicValueEnum`].
+    pub fn from(
+        adapted: Adapted,
+        downcast_fn: ValueDowncastFn<'ctx, T>,
+        upcast_fn: ValueUpcastFn<'ctx, T>,
+    ) -> Self {
+        TypedArrayLikeAdapter { adapted, downcast_fn, upcast_fn }
+    }
+}
+
+impl<'ctx, T, Adapted> ArrayLikeValue<'ctx> for TypedArrayLikeAdapter<'ctx, T, Adapted>
+where
+    Adapted: ArrayLikeValue<'ctx>,
+{
+    fn element_type<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> AnyTypeEnum<'ctx> {
+        self.adapted.element_type(ctx, generator)
+    }
+
+    fn base_ptr<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> PointerValue<'ctx> {
+        self.adapted.base_ptr(ctx, generator)
+    }
+
+    fn size<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> IntValue<'ctx> {
+        self.adapted.size(ctx, generator)
+    }
+}
+
+impl<'ctx, T, Index, Adapted> ArrayLikeIndexer<'ctx, Index>
+    for TypedArrayLikeAdapter<'ctx, T, Adapted>
+where
+    Adapted: ArrayLikeIndexer<'ctx, Index>,
+{
+    unsafe fn ptr_offset_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        unsafe { self.adapted.ptr_offset_unchecked(ctx, generator, idx, name) }
+    }
+
+    fn ptr_offset<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &Index,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        self.adapted.ptr_offset(ctx, generator, idx, name)
+    }
+}
+
+impl<'ctx, T, Index, Adapted> UntypedArrayLikeAccessor<'ctx, Index>
+    for TypedArrayLikeAdapter<'ctx, T, Adapted>
+where
+    Adapted: UntypedArrayLikeAccessor<'ctx, Index>,
+{
+}
+impl<'ctx, T, Index, Adapted> UntypedArrayLikeMutator<'ctx, Index>
+    for TypedArrayLikeAdapter<'ctx, T, Adapted>
+where
+    Adapted: UntypedArrayLikeMutator<'ctx, Index>,
+{
+}
+
+impl<'ctx, T, Index, Adapted> TypedArrayLikeAccessor<'ctx, T, Index>
+    for TypedArrayLikeAdapter<'ctx, T, Adapted>
+where
+    Adapted: UntypedArrayLikeAccessor<'ctx, Index>,
+{
+    fn downcast_to_type(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        value: BasicValueEnum<'ctx>,
+    ) -> T {
+        (self.downcast_fn)(ctx, value)
+    }
+}
+
+impl<'ctx, T, Index, Adapted> TypedArrayLikeMutator<'ctx, T, Index>
+    for TypedArrayLikeAdapter<'ctx, T, Adapted>
+where
+    Adapted: UntypedArrayLikeMutator<'ctx, Index>,
+{
+    fn upcast_from_type(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        value: T,
+    ) -> BasicValueEnum<'ctx> {
+        (self.upcast_fn)(ctx, value)
+    }
+}
+
+/// An LLVM value representing an array slice, consisting of a pointer to the data and the size of
+/// the slice.
+#[derive(Copy, Clone)]
+pub struct ArraySliceValue<'ctx>(PointerValue<'ctx>, IntValue<'ctx>, Option<&'ctx str>);
+
+impl<'ctx> ArraySliceValue<'ctx> {
+    /// Creates an [`ArraySliceValue`] from a [`PointerValue`] and its size.
+    #[must_use]
+    pub fn from_ptr_val(
+        ptr: PointerValue<'ctx>,
+        size: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> Self {
+        ArraySliceValue(ptr, size, name)
+    }
+}
+
+impl<'ctx> From<ArraySliceValue<'ctx>> for PointerValue<'ctx> {
+    fn from(value: ArraySliceValue<'ctx>) -> Self {
+        value.0
+    }
+}
+
+impl<'ctx> ArrayLikeValue<'ctx> for ArraySliceValue<'ctx> {
+    fn element_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> AnyTypeEnum<'ctx> {
+        self.0.get_type().get_element_type()
+    }
+
+    fn base_ptr<G: CodeGenerator + ?Sized>(
+        &self,
+        _: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> PointerValue<'ctx> {
+        self.0
+    }
+
+    fn size<G: CodeGenerator + ?Sized>(
+        &self,
+        _: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> IntValue<'ctx> {
+        self.1
+    }
+}
+
+impl<'ctx> ArrayLikeIndexer<'ctx> for ArraySliceValue<'ctx> {
+    unsafe fn ptr_offset_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let var_name = name.map(|v| format!("{v}.addr")).unwrap_or_default();
+
+        unsafe {
+            ctx.builder
+                .build_in_bounds_gep(self.base_ptr(ctx, generator), &[*idx], var_name.as_str())
+                .unwrap()
+        }
+    }
+
+    fn ptr_offset<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        debug_assert_eq!(idx.get_type(), generator.get_size_type(ctx.ctx));
+
+        let size = self.size(ctx, generator);
+        let in_range = ctx.builder.build_int_compare(IntPredicate::ULT, *idx, size, "").unwrap();
+        ctx.make_assert(
+            generator,
+            in_range,
+            "0:IndexError",
+            "list index out of range",
+            [None, None, None],
+            ctx.current_loc,
+        );
+
+        unsafe { self.ptr_offset_unchecked(ctx, generator, idx, name) }
+    }
+}
+
+impl<'ctx> UntypedArrayLikeAccessor<'ctx> for ArraySliceValue<'ctx> {}
+impl<'ctx> UntypedArrayLikeMutator<'ctx> for ArraySliceValue<'ctx> {}

nac3core/src/codegen/values/list.rs

@@ -0,0 +1,241 @@
+use inkwell::{
+    types::{AnyTypeEnum, BasicType, BasicTypeEnum, IntType},
+    values::{BasicValueEnum, IntValue, PointerValue},
+    AddressSpace, IntPredicate,
+};
+
+use super::{
+    ArrayLikeIndexer, ArrayLikeValue, ProxyValue, UntypedArrayLikeAccessor, UntypedArrayLikeMutator,
+};
+use crate::codegen::{
+    types::ListType,
+    {CodeGenContext, CodeGenerator},
+};
+
+/// Proxy type for accessing a `list` value in LLVM.
+#[derive(Copy, Clone)]
+pub struct ListValue<'ctx> {
+    value: PointerValue<'ctx>,
+    llvm_usize: IntType<'ctx>,
+    name: Option<&'ctx str>,
+}
+
+impl<'ctx> ListValue<'ctx> {
+    /// Checks whether `value` is an instance of `list`, returning [Err] if `value` is not an
+    /// instance.
+    pub fn is_representable(
+        value: PointerValue<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        ListType::is_representable(value.get_type(), llvm_usize)
+    }
+
+    /// Creates an [`ListValue`] from a [`PointerValue`].
+    #[must_use]
+    pub fn from_pointer_value(
+        ptr: PointerValue<'ctx>,
+        llvm_usize: IntType<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> Self {
+        debug_assert!(Self::is_representable(ptr, llvm_usize).is_ok());
+
+        ListValue { value: ptr, llvm_usize, name }
+    }
+
+    /// Returns the double-indirection pointer to the `data` array, as if by calling `getelementptr`
+    /// on the field.
+    fn pptr_to_data(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        let llvm_i32 = ctx.ctx.i32_type();
+        let var_name = self.name.map(|v| format!("{v}.data.addr")).unwrap_or_default();
+
+        unsafe {
+            ctx.builder
+                .build_in_bounds_gep(
+                    self.as_base_value(),
+                    &[llvm_i32.const_zero(), llvm_i32.const_zero()],
+                    var_name.as_str(),
+                )
+                .unwrap()
+        }
+    }
+
+    /// Returns the pointer to the field storing the size of this `list`.
+    fn ptr_to_size(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        let llvm_i32 = ctx.ctx.i32_type();
+        let var_name = self.name.map(|v| format!("{v}.size.addr")).unwrap_or_default();
+
+        unsafe {
+            ctx.builder
+                .build_in_bounds_gep(
+                    self.as_base_value(),
+                    &[llvm_i32.const_zero(), llvm_i32.const_int(1, true)],
+                    var_name.as_str(),
+                )
+                .unwrap()
+        }
+    }
+
+    /// Stores the array of data elements `data` into this instance.
+    fn store_data(&self, ctx: &CodeGenContext<'ctx, '_>, data: PointerValue<'ctx>) {
+        ctx.builder.build_store(self.pptr_to_data(ctx), data).unwrap();
+    }
+
+    /// Convenience method for creating a new array storing data elements with the given element
+    /// type `elem_ty` and `size`.
+    ///
+    /// If `size` is [None], the size stored in the field of this instance is used instead.
+    pub fn create_data(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        elem_ty: BasicTypeEnum<'ctx>,
+        size: Option<IntValue<'ctx>>,
+    ) {
+        let size = size.unwrap_or_else(|| self.load_size(ctx, None));
+
+        let data = ctx
+            .builder
+            .build_select(
+                ctx.builder
+                    .build_int_compare(IntPredicate::NE, size, self.llvm_usize.const_zero(), "")
+                    .unwrap(),
+                ctx.builder.build_array_alloca(elem_ty, size, "").unwrap(),
+                elem_ty.ptr_type(AddressSpace::default()).const_zero(),
+                "",
+            )
+            .map(BasicValueEnum::into_pointer_value)
+            .unwrap();
+        self.store_data(ctx, data);
+    }
+
+    /// Returns the double-indirection pointer to the `data` array, as if by calling `getelementptr`
+    /// on the field.
+    #[must_use]
+    pub fn data(&self) -> ListDataProxy<'ctx, '_> {
+        ListDataProxy(self)
+    }
+
+    /// Stores the `size` of this `list` into this instance.
+    pub fn store_size<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+        size: IntValue<'ctx>,
+    ) {
+        debug_assert_eq!(size.get_type(), generator.get_size_type(ctx.ctx));
+
+        let psize = self.ptr_to_size(ctx);
+        ctx.builder.build_store(psize, size).unwrap();
+    }
+
+    /// Returns the size of this `list` as a value.
+    pub fn load_size(&self, ctx: &CodeGenContext<'ctx, '_>, name: Option<&str>) -> IntValue<'ctx> {
+        let psize = self.ptr_to_size(ctx);
+        let var_name = name
+            .map(ToString::to_string)
+            .or_else(|| self.name.map(|v| format!("{v}.size")))
+            .unwrap_or_default();
+
+        ctx.builder
+            .build_load(psize, var_name.as_str())
+            .map(BasicValueEnum::into_int_value)
+            .unwrap()
+    }
+}
+
+impl<'ctx> ProxyValue<'ctx> for ListValue<'ctx> {
+    type Base = PointerValue<'ctx>;
+    type Type = ListType<'ctx>;
+
+    fn get_type(&self) -> Self::Type {
+        ListType::from_type(self.as_base_value().get_type(), self.llvm_usize)
+    }
+
+    fn as_base_value(&self) -> Self::Base {
+        self.value
+    }
+}
+
+impl<'ctx> From<ListValue<'ctx>> for PointerValue<'ctx> {
+    fn from(value: ListValue<'ctx>) -> Self {
+        value.as_base_value()
+    }
+}
+
+/// Proxy type for accessing the `data` array of an `list` instance in LLVM.
+#[derive(Copy, Clone)]
+pub struct ListDataProxy<'ctx, 'a>(&'a ListValue<'ctx>);
+
+impl<'ctx> ArrayLikeValue<'ctx> for ListDataProxy<'ctx, '_> {
+    fn element_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> AnyTypeEnum<'ctx> {
+        self.0.value.get_type().get_element_type()
+    }
+
+    fn base_ptr<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> PointerValue<'ctx> {
+        let var_name = self.0.name.map(|v| format!("{v}.data")).unwrap_or_default();
+
+        ctx.builder
+            .build_load(self.0.pptr_to_data(ctx), var_name.as_str())
+            .map(BasicValueEnum::into_pointer_value)
+            .unwrap()
+    }
+
+    fn size<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> IntValue<'ctx> {
+        self.0.load_size(ctx, None)
+    }
+}
+
+impl<'ctx> ArrayLikeIndexer<'ctx> for ListDataProxy<'ctx, '_> {
+    unsafe fn ptr_offset_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let var_name = name.map(|v| format!("{v}.addr")).unwrap_or_default();
+
+        unsafe {
+            ctx.builder
+                .build_in_bounds_gep(self.base_ptr(ctx, generator), &[*idx], var_name.as_str())
+                .unwrap()
+        }
+    }
+
+    fn ptr_offset<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        debug_assert_eq!(idx.get_type(), generator.get_size_type(ctx.ctx));
+
+        let size = self.size(ctx, generator);
+        let in_range = ctx.builder.build_int_compare(IntPredicate::ULT, *idx, size, "").unwrap();
+        ctx.make_assert(
+            generator,
+            in_range,
+            "0:IndexError",
+            "list index out of range",
+            [None, None, None],
+            ctx.current_loc,
+        );
+
+        unsafe { self.ptr_offset_unchecked(ctx, generator, idx, name) }
+    }
+}
+
+impl<'ctx> UntypedArrayLikeAccessor<'ctx> for ListDataProxy<'ctx, '_> {}
+impl<'ctx> UntypedArrayLikeMutator<'ctx> for ListDataProxy<'ctx, '_> {}

nac3core/src/codegen/values/mod.rs

@@ -0,0 +1,47 @@
+use inkwell::{context::Context, values::BasicValue};
+
+use super::types::ProxyType;
+use crate::codegen::CodeGenerator;
+pub use array::*;
+pub use list::*;
+pub use range::*;
+
+mod array;
+mod list;
+pub mod ndarray;
+mod range;
+pub mod utils;
+
+/// A LLVM type that is used to represent a non-primitive value in NAC3.
+pub trait ProxyValue<'ctx>: Into<Self::Base> {
+    /// The type of LLVM values represented by this instance. This is usually the
+    /// [LLVM pointer type][PointerValue].
+    type Base: BasicValue<'ctx>;
+
+    /// The type of this value.
+    type Type: ProxyType<'ctx, Value = Self>;
+
+    /// Checks whether `value` can be represented by this [`ProxyValue`].
+    fn is_instance<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        value: impl BasicValue<'ctx>,
+    ) -> Result<(), String> {
+        Self::Type::is_type(generator, ctx, value.as_basic_value_enum().get_type())
+    }
+
+    /// Checks whether `value` can be represented by this [`ProxyValue`].
+    fn is_representable<G: CodeGenerator + ?Sized>(
+        generator: &G,
+        ctx: &'ctx Context,
+        value: Self::Base,
+    ) -> Result<(), String> {
+        Self::is_instance(generator, ctx, value.as_basic_value_enum())
+    }
+
+    /// Returns the [type][ProxyType] of this value.
+    fn get_type(&self) -> Self::Type;
+
+    /// Returns the [base value][Self::Base] of this proxy.
+    fn as_base_value(&self) -> Self::Base;
+}

nac3core/src/codegen/values/ndarray/contiguous.rs

@@ -0,0 +1,202 @@
+use inkwell::{
+    types::{BasicType, BasicTypeEnum, IntType},
+    values::{IntValue, PointerValue},
+    AddressSpace,
+};
+
+use super::{ArrayLikeValue, NDArrayValue, ProxyValue};
+use crate::codegen::{
+    stmt::gen_if_callback,
+    types::{
+        ndarray::{ContiguousNDArrayType, NDArrayType},
+        structure::StructField,
+    },
+    CodeGenContext, CodeGenerator,
+};
+
+#[derive(Copy, Clone)]
+pub struct ContiguousNDArrayValue<'ctx> {
+    value: PointerValue<'ctx>,
+    item: BasicTypeEnum<'ctx>,
+    llvm_usize: IntType<'ctx>,
+    name: Option<&'ctx str>,
+}
+
+impl<'ctx> ContiguousNDArrayValue<'ctx> {
+    /// Checks whether `value` is an instance of `ContiguousNDArray`, returning [Err] if `value` is
+    /// not an instance.
+    pub fn is_representable(
+        value: PointerValue<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        <Self as ProxyValue<'ctx>>::Type::is_representable(value.get_type(), llvm_usize)
+    }
+
+    /// Creates an [`ContiguousNDArrayValue`] from a [`PointerValue`].
+    #[must_use]
+    pub fn from_pointer_value(
+        ptr: PointerValue<'ctx>,
+        dtype: BasicTypeEnum<'ctx>,
+        llvm_usize: IntType<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> Self {
+        debug_assert!(Self::is_representable(ptr, llvm_usize).is_ok());
+
+        Self { value: ptr, item: dtype, llvm_usize, name }
+    }
+
+    fn ndims_field(&self) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields().ndims
+    }
+
+    pub fn store_ndims(&self, ctx: &CodeGenContext<'ctx, '_>, value: IntValue<'ctx>) {
+        self.ndims_field().set(ctx, self.as_base_value(), value, self.name);
+    }
+
+    fn shape_field(&self) -> StructField<'ctx, PointerValue<'ctx>> {
+        self.get_type().get_fields().shape
+    }
+
+    pub fn store_shape(&self, ctx: &CodeGenContext<'ctx, '_>, value: PointerValue<'ctx>) {
+        self.shape_field().set(ctx, self.as_base_value(), value, self.name);
+    }
+
+    pub fn load_shape(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        self.shape_field().get(ctx, self.value, self.name)
+    }
+
+    fn data_field(&self) -> StructField<'ctx, PointerValue<'ctx>> {
+        self.get_type().get_fields().data
+    }
+
+    pub fn store_data(&self, ctx: &CodeGenContext<'ctx, '_>, value: PointerValue<'ctx>) {
+        self.data_field().set(ctx, self.as_base_value(), value, self.name);
+    }
+
+    pub fn load_data(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        self.data_field().get(ctx, self.value, self.name)
+    }
+}
+
+impl<'ctx> ProxyValue<'ctx> for ContiguousNDArrayValue<'ctx> {
+    type Base = PointerValue<'ctx>;
+    type Type = ContiguousNDArrayType<'ctx>;
+
+    fn get_type(&self) -> Self::Type {
+        <Self as ProxyValue<'ctx>>::Type::from_type(
+            self.as_base_value().get_type(),
+            self.item,
+            self.llvm_usize,
+        )
+    }
+
+    fn as_base_value(&self) -> Self::Base {
+        self.value
+    }
+}
+
+impl<'ctx> From<ContiguousNDArrayValue<'ctx>> for PointerValue<'ctx> {
+    fn from(value: ContiguousNDArrayValue<'ctx>) -> Self {
+        value.as_base_value()
+    }
+}
+
+impl<'ctx> NDArrayValue<'ctx> {
+    /// Create a [`ContiguousNDArrayValue`] from the contents of this ndarray.
+    ///
+    /// This function may or may not be expensive depending on if this ndarray has contiguous data.
+    ///
+    /// If this ndarray is not C-contiguous, this function will allocate memory on the stack for the
+    /// `data` field of the returned [`ContiguousNDArrayValue`] and copy contents of this ndarray to
+    /// there.
+    ///
+    /// If this ndarray is C-contiguous, contents of this ndarray will not be copied. The created
+    /// [`ContiguousNDArrayValue`] will share memory with this ndarray.
+    pub fn make_contiguous_ndarray<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+    ) -> ContiguousNDArrayValue<'ctx> {
+        let result = ContiguousNDArrayType::new(generator, ctx.ctx, self.dtype)
+            .alloca(generator, ctx, self.name);
+
+        // Set ndims and shape.
+        let ndims = self
+            .ndims
+            .map_or_else(|| self.load_ndims(ctx), |ndims| self.llvm_usize.const_int(ndims, false));
+        result.store_ndims(ctx, ndims);
+
+        let shape = self.shape();
+        result.store_shape(ctx, shape.base_ptr(ctx, generator));
+
+        gen_if_callback(
+            generator,
+            ctx,
+            |generator, ctx| Ok(self.is_c_contiguous(generator, ctx)),
+            |_, ctx| {
+                // This ndarray is contiguous.
+                let data = self.data_field(ctx).get(ctx, self.as_base_value(), self.name);
+                let data = ctx
+                    .builder
+                    .build_pointer_cast(data, result.item.ptr_type(AddressSpace::default()), "")
+                    .unwrap();
+                result.store_data(ctx, data);
+
+                Ok(())
+            },
+            |generator, ctx| {
+                // This ndarray is not contiguous. Do a full-copy on `data`. `make_copy` produces an
+                // ndarray with contiguous `data`.
+                let copied_ndarray = self.make_copy(generator, ctx);
+                let data = copied_ndarray.data().base_ptr(ctx, generator);
+                let data = ctx
+                    .builder
+                    .build_pointer_cast(data, result.item.ptr_type(AddressSpace::default()), "")
+                    .unwrap();
+                result.store_data(ctx, data);
+
+                Ok(())
+            },
+        )
+        .unwrap();
+
+        result
+    }
+
+    /// Create an [`NDArrayValue`] from a [`ContiguousNDArrayValue`].
+    ///
+    /// The operation is cheap. The newly created [`NDArrayValue`] will share the same memory as the
+    /// [`ContiguousNDArrayValue`].
+    ///
+    /// `ndims` has to be provided as [`NDArrayValue`] requires a statically known `ndims` value,
+    /// despite the fact that the information should be contained within the
+    /// [`ContiguousNDArrayValue`].
+    pub fn from_contiguous_ndarray<G: CodeGenerator + ?Sized>(
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        carray: ContiguousNDArrayValue<'ctx>,
+        ndims: u64,
+    ) -> Self {
+        // TODO: Debug assert `ndims == carray.ndims` to catch bugs.
+
+        // Allocate the resulting ndarray.
+        let ndarray = NDArrayType::new(generator, ctx.ctx, carray.item, Some(ndims))
+            .construct_uninitialized(generator, ctx, carray.name);
+
+        // Copy shape and update strides
+        let shape = carray.load_shape(ctx);
+        ndarray.copy_shape_from_array(generator, ctx, shape);
+        ndarray.set_strides_contiguous(generator, ctx);
+
+        // Share data
+        let data = carray.load_data(ctx);
+        ndarray.store_data(
+            ctx,
+            ctx.builder
+                .build_pointer_cast(data, ctx.ctx.i8_type().ptr_type(AddressSpace::default()), "")
+                .unwrap(),
+        );
+
+        ndarray
+    }
+}

nac3core/src/codegen/values/ndarray/indexing.rs

@@ -0,0 +1,262 @@
+use inkwell::{
+    types::IntType,
+    values::{IntValue, PointerValue},
+    AddressSpace,
+};
+use itertools::Itertools;
+
+use nac3parser::ast::{Expr, ExprKind};
+
+use crate::{
+    codegen::{
+        irrt,
+        types::{
+            ndarray::{NDArrayType, NDIndexType},
+            structure::StructField,
+            utils::SliceType,
+        },
+        values::{ndarray::NDArrayValue, utils::RustSlice, ProxyValue},
+        CodeGenContext, CodeGenerator,
+    },
+    typecheck::typedef::Type,
+};
+
+/// An IRRT representation of an ndarray subscript index.
+#[derive(Copy, Clone)]
+pub struct NDIndexValue<'ctx> {
+    value: PointerValue<'ctx>,
+    llvm_usize: IntType<'ctx>,
+    name: Option<&'ctx str>,
+}
+
+impl<'ctx> NDIndexValue<'ctx> {
+    /// Checks whether `value` is an instance of `ndindex`, returning [Err] if `value` is not an
+    /// instance.
+    pub fn is_representable(
+        value: PointerValue<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        <Self as ProxyValue<'ctx>>::Type::is_representable(value.get_type(), llvm_usize)
+    }
+
+    /// Creates an [`NDIndexValue`] from a [`PointerValue`].
+    #[must_use]
+    pub fn from_pointer_value(
+        ptr: PointerValue<'ctx>,
+        llvm_usize: IntType<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> Self {
+        debug_assert!(Self::is_representable(ptr, llvm_usize).is_ok());
+
+        Self { value: ptr, llvm_usize, name }
+    }
+
+    fn type_field(&self) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields().type_
+    }
+
+    pub fn load_type(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        self.type_field().get(ctx, self.value, self.name)
+    }
+
+    pub fn store_type(&self, ctx: &CodeGenContext<'ctx, '_>, value: IntValue<'ctx>) {
+        self.type_field().set(ctx, self.value, value, self.name);
+    }
+
+    fn data_field(&self) -> StructField<'ctx, PointerValue<'ctx>> {
+        self.get_type().get_fields().data
+    }
+
+    pub fn load_data(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        self.data_field().get(ctx, self.value, self.name)
+    }
+
+    pub fn store_data(&self, ctx: &CodeGenContext<'ctx, '_>, value: PointerValue<'ctx>) {
+        self.data_field().set(ctx, self.value, value, self.name);
+    }
+}
+
+impl<'ctx> ProxyValue<'ctx> for NDIndexValue<'ctx> {
+    type Base = PointerValue<'ctx>;
+    type Type = NDIndexType<'ctx>;
+
+    fn get_type(&self) -> Self::Type {
+        Self::Type::from_type(self.value.get_type(), self.llvm_usize)
+    }
+
+    fn as_base_value(&self) -> Self::Base {
+        self.value
+    }
+}
+
+impl<'ctx> From<NDIndexValue<'ctx>> for PointerValue<'ctx> {
+    fn from(value: NDIndexValue<'ctx>) -> Self {
+        value.as_base_value()
+    }
+}
+
+impl<'ctx> NDArrayValue<'ctx> {
+    /// Get the expected `ndims` after indexing with `indices`.
+    #[must_use]
+    fn deduce_ndims_after_indexing_with(&self, indices: &[RustNDIndex<'ctx>]) -> Option<u64> {
+        let mut ndims = self.ndims?;
+
+        for index in indices {
+            match index {
+                RustNDIndex::SingleElement(_) => {
+                    ndims -= 1; // Single elements decrements ndims
+                }
+                RustNDIndex::NewAxis => {
+                    ndims += 1; // `np.newaxis` / `none` adds a new axis
+                }
+                RustNDIndex::Ellipsis | RustNDIndex::Slice(_) => {}
+            }
+        }
+
+        Some(ndims)
+    }
+
+    /// Index into the ndarray, and return a newly-allocated view on this ndarray.
+    ///
+    /// This function behaves like NumPy's ndarray indexing, but if the indices index
+    /// into a single element, an unsized ndarray is returned.
+    #[must_use]
+    pub fn index<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        indices: &[RustNDIndex<'ctx>],
+    ) -> Self {
+        assert!(self.ndims.is_some(), "NDArrayValue::index is only supported for instances with compile-time known ndims (self.ndims = Some(...))");
+
+        let dst_ndims = self.deduce_ndims_after_indexing_with(indices);
+        let dst_ndarray = NDArrayType::new(generator, ctx.ctx, self.dtype, dst_ndims)
+            .construct_uninitialized(generator, ctx, None);
+
+        let indices =
+            NDIndexType::new(generator, ctx.ctx).construct_ndindices(generator, ctx, indices);
+        irrt::ndarray::call_nac3_ndarray_index(generator, ctx, indices, *self, dst_ndarray);
+
+        dst_ndarray
+    }
+}
+
+/// A convenience enum representing a [`NDIndexValue`].
+// TODO: Rename to CTConstNDIndex
+#[derive(Debug, Clone)]
+pub enum RustNDIndex<'ctx> {
+    SingleElement(IntValue<'ctx>),
+    Slice(RustSlice<'ctx>),
+    NewAxis,
+    Ellipsis,
+}
+
+impl<'ctx> RustNDIndex<'ctx> {
+    /// Generate LLVM code to transform an ndarray subscript expression to
+    /// its list of [`RustNDIndex`]
+    ///
+    /// i.e.,
+    /// ```python
+    /// my_ndarray[::3, 1, :2:]
+    ///            ^^^^^^^^^^^ Then these into a three `RustNDIndex`es
+    /// ```
+    pub fn from_subscript_expr<G: CodeGenerator>(
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        subscript: &Expr<Option<Type>>,
+    ) -> Result<Vec<RustNDIndex<'ctx>>, String> {
+        // Annoying notes about `slice`
+        //  - `my_array[5]`
+        //    - slice is a `Constant`
+        //  - `my_array[:5]`
+        //    - slice is a `Slice`
+        //  - `my_array[:]`
+        //    - slice is a `Slice`, but lower upper step would all be `Option::None`
+        //  - `my_array[:, :]`
+        //    - slice is now a `Tuple` of two `Slice`-s
+        //
+        // In summary:
+        //  - when there is a comma "," within [], `slice` will be a `Tuple` of the entries.
+        //  - when there is not comma "," within [] (i.e., just a single entry), `slice` will be that entry itself.
+        //
+        // So we first "flatten" out the slice expression
+        let index_exprs = match &subscript.node {
+            ExprKind::Tuple { elts, .. } => elts.iter().collect_vec(),
+            _ => vec![subscript],
+        };
+
+        // Process all index expressions
+        let mut rust_ndindices: Vec<RustNDIndex> = Vec::with_capacity(index_exprs.len()); // Not using iterators here because `?` is used here.
+        for index_expr in index_exprs {
+            // NOTE: Currently nac3core's slices do not have an object representation,
+            // so the code/implementation looks awkward - we have to do pattern matching on the expression
+            let ndindex = if let ExprKind::Slice { lower, upper, step } = &index_expr.node {
+                // Handle slices
+                let slice = RustSlice::from_slice_expr(generator, ctx, lower, upper, step)?;
+                RustNDIndex::Slice(slice)
+            } else {
+                // Treat and handle everything else as a single element index.
+                let index = generator.gen_expr(ctx, index_expr)?.unwrap().to_basic_value_enum(
+                    ctx,
+                    generator,
+                    ctx.primitives.int32, // Must be int32, this checks for illegal values
+                )?;
+                let index = index.into_int_value();
+
+                RustNDIndex::SingleElement(index)
+            };
+            rust_ndindices.push(ndindex);
+        }
+        Ok(rust_ndindices)
+    }
+
+    /// Get the value to set `NDIndex::type` for this variant.
+    #[must_use]
+    pub fn get_type_id(&self) -> u64 {
+        // Defined in IRRT, must be in sync
+        match self {
+            RustNDIndex::SingleElement(_) => 0,
+            RustNDIndex::Slice(_) => 1,
+            RustNDIndex::NewAxis => 2,
+            RustNDIndex::Ellipsis => 3,
+        }
+    }
+
+    /// Serialize this [`RustNDIndex`] by writing it into an LLVM [`NDIndexValue`].
+    pub fn write_to_ndindex<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        dst_ndindex: NDIndexValue<'ctx>,
+    ) {
+        let llvm_pi8 = ctx.ctx.i8_type().ptr_type(AddressSpace::default());
+
+        // Set `dst_ndindex.type`
+        dst_ndindex.store_type(ctx, ctx.ctx.i8_type().const_int(self.get_type_id(), false));
+
+        // Set `dst_ndindex_ptr->data`
+        match self {
+            RustNDIndex::SingleElement(in_index) => {
+                let index_ptr = ctx.builder.build_alloca(ctx.ctx.i32_type(), "").unwrap();
+                ctx.builder.build_store(index_ptr, *in_index).unwrap();
+
+                dst_ndindex.store_data(
+                    ctx,
+                    ctx.builder.build_pointer_cast(index_ptr, llvm_pi8, "").unwrap(),
+                );
+            }
+            RustNDIndex::Slice(in_rust_slice) => {
+                let user_slice_ptr =
+                    SliceType::new(ctx.ctx, ctx.ctx.i32_type(), generator.get_size_type(ctx.ctx))
+                        .alloca(generator, ctx, None);
+                in_rust_slice.write_to_slice(ctx, user_slice_ptr);
+
+                dst_ndindex.store_data(
+                    ctx,
+                    ctx.builder.build_pointer_cast(user_slice_ptr.into(), llvm_pi8, "").unwrap(),
+                );
+            }
+            RustNDIndex::NewAxis | RustNDIndex::Ellipsis => {}
+        }
+    }
+}

nac3core/src/codegen/values/ndarray/mod.rs

@@ -0,0 +1,933 @@
+use inkwell::{
+    types::{AnyType, AnyTypeEnum, BasicType, BasicTypeEnum, IntType},
+    values::{BasicValueEnum, IntValue, PointerValue},
+    AddressSpace, IntPredicate,
+};
+
+use super::{
+    ArrayLikeIndexer, ArrayLikeValue, ProxyValue, TypedArrayLikeAccessor, TypedArrayLikeMutator,
+    UntypedArrayLikeAccessor, UntypedArrayLikeMutator,
+};
+use crate::codegen::{
+    irrt,
+    llvm_intrinsics::{call_int_umin, call_memcpy_generic_array},
+    stmt::gen_for_callback_incrementing,
+    type_aligned_alloca,
+    types::{ndarray::NDArrayType, structure::StructField},
+    CodeGenContext, CodeGenerator,
+};
+pub use contiguous::*;
+pub use indexing::*;
+pub use nditer::*;
+pub use view::*;
+
+mod contiguous;
+mod indexing;
+mod nditer;
+mod view;
+
+/// Proxy type for accessing an `NDArray` value in LLVM.
+#[derive(Copy, Clone)]
+pub struct NDArrayValue<'ctx> {
+    value: PointerValue<'ctx>,
+    dtype: BasicTypeEnum<'ctx>,
+    ndims: Option<u64>,
+    llvm_usize: IntType<'ctx>,
+    name: Option<&'ctx str>,
+}
+
+impl<'ctx> NDArrayValue<'ctx> {
+    /// Checks whether `value` is an instance of `NDArray`, returning [Err] if `value` is not an
+    /// instance.
+    pub fn is_representable(
+        value: PointerValue<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        NDArrayType::is_representable(value.get_type(), llvm_usize)
+    }
+
+    /// Creates an [`NDArrayValue`] from a [`PointerValue`].
+    #[must_use]
+    pub fn from_pointer_value(
+        ptr: PointerValue<'ctx>,
+        dtype: BasicTypeEnum<'ctx>,
+        ndims: Option<u64>,
+        llvm_usize: IntType<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> Self {
+        debug_assert!(Self::is_representable(ptr, llvm_usize).is_ok());
+
+        NDArrayValue { value: ptr, dtype, ndims, llvm_usize, name }
+    }
+
+    fn ndims_field(&self, ctx: &CodeGenContext<'ctx, '_>) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields(ctx.ctx).ndims
+    }
+
+    /// Returns the pointer to the field storing the number of dimensions of this `NDArray`.
+    fn ptr_to_ndims(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        self.ndims_field(ctx).ptr_by_gep(ctx, self.value, self.name)
+    }
+
+    /// Stores the number of dimensions `ndims` into this instance.
+    pub fn store_ndims<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+        ndims: IntValue<'ctx>,
+    ) {
+        debug_assert_eq!(ndims.get_type(), generator.get_size_type(ctx.ctx));
+
+        let pndims = self.ptr_to_ndims(ctx);
+        ctx.builder.build_store(pndims, ndims).unwrap();
+    }
+
+    /// Returns the number of dimensions of this `NDArray` as a value.
+    pub fn load_ndims(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        let pndims = self.ptr_to_ndims(ctx);
+        ctx.builder.build_load(pndims, "").map(BasicValueEnum::into_int_value).unwrap()
+    }
+
+    fn itemsize_field(&self, ctx: &CodeGenContext<'ctx, '_>) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields(ctx.ctx).itemsize
+    }
+
+    /// Stores the size of each element `itemsize` into this instance.
+    pub fn store_itemsize<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+        itemsize: IntValue<'ctx>,
+    ) {
+        debug_assert_eq!(itemsize.get_type(), generator.get_size_type(ctx.ctx));
+
+        self.itemsize_field(ctx).set(ctx, self.value, itemsize, self.name);
+    }
+
+    /// Returns the size of each element of this `NDArray` as a value.
+    pub fn load_itemsize(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        self.itemsize_field(ctx).get(ctx, self.value, self.name)
+    }
+
+    fn shape_field(&self, ctx: &CodeGenContext<'ctx, '_>) -> StructField<'ctx, PointerValue<'ctx>> {
+        self.get_type().get_fields(ctx.ctx).shape
+    }
+
+    /// Returns the double-indirection pointer to the `shape` array, as if by calling
+    /// `getelementptr` on the field.
+    fn ptr_to_shape(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        self.shape_field(ctx).ptr_by_gep(ctx, self.value, self.name)
+    }
+
+    /// Stores the array of dimension sizes `dims` into this instance.
+    fn store_shape(&self, ctx: &CodeGenContext<'ctx, '_>, dims: PointerValue<'ctx>) {
+        self.shape_field(ctx).set(ctx, self.as_base_value(), dims, self.name);
+    }
+
+    /// Convenience method for creating a new array storing dimension sizes with the given `size`.
+    pub fn create_shape(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        llvm_usize: IntType<'ctx>,
+        size: IntValue<'ctx>,
+    ) {
+        self.store_shape(ctx, ctx.builder.build_array_alloca(llvm_usize, size, "").unwrap());
+    }
+
+    /// Returns a proxy object to the field storing the size of each dimension of this `NDArray`.
+    #[must_use]
+    pub fn shape(&self) -> NDArrayShapeProxy<'ctx, '_> {
+        NDArrayShapeProxy(self)
+    }
+
+    fn strides_field(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) -> StructField<'ctx, PointerValue<'ctx>> {
+        self.get_type().get_fields(ctx.ctx).strides
+    }
+
+    /// Returns the double-indirection pointer to the `strides` array, as if by calling
+    /// `getelementptr` on the field.
+    fn ptr_to_strides(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        self.strides_field(ctx).ptr_by_gep(ctx, self.value, self.name)
+    }
+
+    /// Stores the array of stride sizes `strides` into this instance.
+    fn store_strides(&self, ctx: &CodeGenContext<'ctx, '_>, strides: PointerValue<'ctx>) {
+        self.strides_field(ctx).set(ctx, self.as_base_value(), strides, self.name);
+    }
+
+    /// Convenience method for creating a new array storing the stride with the given `size`.
+    pub fn create_strides(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        llvm_usize: IntType<'ctx>,
+        size: IntValue<'ctx>,
+    ) {
+        self.store_strides(ctx, ctx.builder.build_array_alloca(llvm_usize, size, "").unwrap());
+    }
+
+    /// Returns a proxy object to the field storing the stride of each dimension of this `NDArray`.
+    #[must_use]
+    pub fn strides(&self) -> NDArrayStridesProxy<'ctx, '_> {
+        NDArrayStridesProxy(self)
+    }
+
+    fn data_field(&self, ctx: &CodeGenContext<'ctx, '_>) -> StructField<'ctx, PointerValue<'ctx>> {
+        self.get_type().get_fields(ctx.ctx).data
+    }
+
+    /// Returns the double-indirection pointer to the `data` array, as if by calling `getelementptr`
+    /// on the field.
+    pub fn ptr_to_data(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        self.data_field(ctx).ptr_by_gep(ctx, self.value, self.name)
+    }
+
+    /// Stores the array of data elements `data` into this instance.
+    fn store_data(&self, ctx: &CodeGenContext<'ctx, '_>, data: PointerValue<'ctx>) {
+        let data = ctx
+            .builder
+            .build_bit_cast(data, ctx.ctx.i8_type().ptr_type(AddressSpace::default()), "")
+            .unwrap();
+        self.data_field(ctx).set(ctx, self.as_base_value(), data.into_pointer_value(), self.name);
+    }
+
+    /// Convenience method for creating a new array storing data elements with the given element
+    /// type `elem_ty` and `size`.
+    ///
+    /// The data buffer will be allocated on the stack, and is considered to be owned by this ndarray instance.
+    ///
+    /// # Safety
+    ///
+    /// The caller must ensure that `shape` and `itemsize` of this ndarray instance is initialized.
+    pub unsafe fn create_data<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+    ) {
+        let nbytes = self.nbytes(generator, ctx);
+
+        let data = type_aligned_alloca(generator, ctx, self.dtype, nbytes, None);
+        self.store_data(ctx, data);
+
+        self.set_strides_contiguous(generator, ctx);
+    }
+
+    /// Returns a proxy object to the field storing the data of this `NDArray`.
+    #[must_use]
+    pub fn data(&self) -> NDArrayDataProxy<'ctx, '_> {
+        NDArrayDataProxy(self)
+    }
+
+    /// Copy shape dimensions from an array.
+    pub fn copy_shape_from_array<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        shape: PointerValue<'ctx>,
+    ) {
+        let num_items = self.load_ndims(ctx);
+
+        call_memcpy_generic_array(
+            ctx,
+            self.shape().base_ptr(ctx, generator),
+            shape,
+            num_items,
+            ctx.ctx.bool_type().const_zero(),
+        );
+    }
+
+    /// Copy shape dimensions from an ndarray.
+    /// Panics if `ndims` mismatches.
+    pub fn copy_shape_from_ndarray<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        src_ndarray: NDArrayValue<'ctx>,
+    ) {
+        if self.ndims.is_some() && src_ndarray.ndims.is_some() {
+            assert_eq!(self.ndims, src_ndarray.ndims);
+        } else {
+            let self_ndims = self.load_ndims(ctx);
+            let src_ndims = src_ndarray.load_ndims(ctx);
+
+            ctx.make_assert(
+                generator,
+                ctx.builder.build_int_compare(
+                    IntPredicate::EQ,
+                    self_ndims,
+                    src_ndims,
+                    ""
+                ).unwrap(),
+                "0:AssertionError",
+                "NDArrayValue::copy_shape_from_ndarray: Expected self.ndims ({0}) == src_ndarray.ndims ({1})",
+                [Some(self_ndims), Some(src_ndims), None],
+                ctx.current_loc
+            );
+        }
+
+        let src_shape = src_ndarray.shape().base_ptr(ctx, generator);
+        self.copy_shape_from_array(generator, ctx, src_shape);
+    }
+
+    /// Copy strides dimensions from an array.
+    pub fn copy_strides_from_array<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        strides: PointerValue<'ctx>,
+    ) {
+        let num_items = self.load_ndims(ctx);
+
+        call_memcpy_generic_array(
+            ctx,
+            self.strides().base_ptr(ctx, generator),
+            strides,
+            num_items,
+            ctx.ctx.bool_type().const_zero(),
+        );
+    }
+
+    /// Copy strides dimensions from an ndarray.
+    /// Panics if `ndims` mismatches.
+    pub fn copy_strides_from_ndarray<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        src_ndarray: NDArrayValue<'ctx>,
+    ) {
+        if self.ndims.is_some() && src_ndarray.ndims.is_some() {
+            assert_eq!(self.ndims, src_ndarray.ndims);
+        } else {
+            let self_ndims = self.load_ndims(ctx);
+            let src_ndims = src_ndarray.load_ndims(ctx);
+
+            ctx.make_assert(
+                generator,
+                ctx.builder.build_int_compare(
+                    IntPredicate::EQ,
+                    self_ndims,
+                    src_ndims,
+                    ""
+                ).unwrap(),
+                "0:AssertionError",
+                "NDArrayValue::copy_shape_from_ndarray: Expected self.ndims ({0}) == src_ndarray.ndims ({1})",
+                [Some(self_ndims), Some(src_ndims), None],
+                ctx.current_loc
+            );
+        }
+
+        let src_strides = src_ndarray.strides().base_ptr(ctx, generator);
+        self.copy_strides_from_array(generator, ctx, src_strides);
+    }
+
+    /// Get the `np.size()` of this ndarray.
+    pub fn size<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) -> IntValue<'ctx> {
+        irrt::ndarray::call_nac3_ndarray_size(generator, ctx, *self)
+    }
+
+    /// Get the `ndarray.nbytes` of this ndarray.
+    pub fn nbytes<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) -> IntValue<'ctx> {
+        irrt::ndarray::call_nac3_ndarray_nbytes(generator, ctx, *self)
+    }
+
+    /// Get the `len()` of this ndarray.
+    pub fn len<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) -> IntValue<'ctx> {
+        irrt::ndarray::call_nac3_ndarray_len(generator, ctx, *self)
+    }
+
+    /// Check if this ndarray is C-contiguous.
+    ///
+    /// See NumPy's `flags["C_CONTIGUOUS"]`: <https://numpy.org/doc/stable/reference/generated/numpy.ndarray.flags.html#numpy.ndarray.flags>
+    pub fn is_c_contiguous<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) -> IntValue<'ctx> {
+        irrt::ndarray::call_nac3_ndarray_is_c_contiguous(generator, ctx, *self)
+    }
+
+    /// Call [`call_nac3_ndarray_set_strides_by_shape`] on this ndarray to update `strides`.
+    ///
+    /// Update the ndarray's strides to make the ndarray contiguous.
+    pub fn set_strides_contiguous<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) {
+        irrt::ndarray::call_nac3_ndarray_set_strides_by_shape(generator, ctx, *self);
+    }
+
+    #[must_use]
+    pub fn make_copy<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+    ) -> Self {
+        let clone = if self.ndims.is_some() {
+            self.get_type().construct_uninitialized(generator, ctx, None)
+        } else {
+            self.get_type().construct_dyn_ndims(generator, ctx, self.load_ndims(ctx), None)
+        };
+
+        let shape = self.shape();
+        clone.copy_shape_from_array(generator, ctx, shape.base_ptr(ctx, generator));
+        unsafe { clone.create_data(generator, ctx) };
+        clone.copy_data_from(generator, ctx, *self);
+        clone
+    }
+
+    /// Copy data from another ndarray.
+    ///
+    /// This ndarray and `src` is that their `np.size()` should be the same. Their shapes
+    /// do not matter. The copying order is determined by how their flattened views look.
+    ///
+    /// Panics if the `dtype`s of ndarrays are different.
+    pub fn copy_data_from<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        src: NDArrayValue<'ctx>,
+    ) {
+        assert_eq!(self.dtype, src.dtype, "self and src dtype should match");
+        irrt::ndarray::call_nac3_ndarray_copy_data(generator, ctx, src, *self);
+    }
+
+    /// Returns true if this ndarray is unsized - `ndims == 0` and only contains a scalar.
+    #[must_use]
+    pub fn is_unsized(&self) -> Option<bool> {
+        self.ndims.map(|ndims| ndims == 0)
+    }
+
+    /// If this ndarray is unsized, return its sole value as an [`AnyObject`].
+    /// Otherwise, do nothing and return the ndarray itself.
+    // TODO: Rename to get_unsized_element
+    pub fn split_unsized<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+    ) -> ScalarOrNDArray<'ctx> {
+        let Some(is_unsized) = self.is_unsized() else { todo!() };
+
+        if is_unsized {
+            // NOTE: `np.size(self) == 0` here is never possible.
+            let zero = generator.get_size_type(ctx.ctx).const_zero();
+            let value = unsafe { self.data().get_unchecked(ctx, generator, &zero, None) };
+
+            ScalarOrNDArray::Scalar(value)
+        } else {
+            ScalarOrNDArray::NDArray(*self)
+        }
+    }
+}
+
+impl<'ctx> ProxyValue<'ctx> for NDArrayValue<'ctx> {
+    type Base = PointerValue<'ctx>;
+    type Type = NDArrayType<'ctx>;
+
+    fn get_type(&self) -> Self::Type {
+        NDArrayType::from_type(
+            self.as_base_value().get_type(),
+            self.dtype,
+            self.ndims,
+            self.llvm_usize,
+        )
+    }
+
+    fn as_base_value(&self) -> Self::Base {
+        self.value
+    }
+}
+
+impl<'ctx> From<NDArrayValue<'ctx>> for PointerValue<'ctx> {
+    fn from(value: NDArrayValue<'ctx>) -> Self {
+        value.as_base_value()
+    }
+}
+
+/// Proxy type for accessing the `shape` array of an `NDArray` instance in LLVM.
+#[derive(Copy, Clone)]
+pub struct NDArrayShapeProxy<'ctx, 'a>(&'a NDArrayValue<'ctx>);
+
+impl<'ctx> ArrayLikeValue<'ctx> for NDArrayShapeProxy<'ctx, '_> {
+    fn element_type<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> AnyTypeEnum<'ctx> {
+        self.0.shape().base_ptr(ctx, generator).get_type().get_element_type()
+    }
+
+    fn base_ptr<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> PointerValue<'ctx> {
+        self.0.shape_field(ctx).get(ctx, self.0.as_base_value(), self.0.name)
+    }
+
+    fn size<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> IntValue<'ctx> {
+        self.0.load_ndims(ctx)
+    }
+}
+
+impl<'ctx> ArrayLikeIndexer<'ctx, IntValue<'ctx>> for NDArrayShapeProxy<'ctx, '_> {
+    unsafe fn ptr_offset_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let var_name = name.map(|v| format!("{v}.addr")).unwrap_or_default();
+
+        unsafe {
+            ctx.builder
+                .build_in_bounds_gep(self.base_ptr(ctx, generator), &[*idx], var_name.as_str())
+                .unwrap()
+        }
+    }
+
+    fn ptr_offset<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let size = self.size(ctx, generator);
+        let in_range = ctx.builder.build_int_compare(IntPredicate::ULT, *idx, size, "").unwrap();
+        ctx.make_assert(
+            generator,
+            in_range,
+            "0:IndexError",
+            "index {0} is out of bounds for axis 0 with size {1}",
+            [Some(*idx), Some(self.0.load_ndims(ctx)), None],
+            ctx.current_loc,
+        );
+
+        unsafe { self.ptr_offset_unchecked(ctx, generator, idx, name) }
+    }
+}
+
+impl<'ctx> UntypedArrayLikeAccessor<'ctx, IntValue<'ctx>> for NDArrayShapeProxy<'ctx, '_> {}
+impl<'ctx> UntypedArrayLikeMutator<'ctx, IntValue<'ctx>> for NDArrayShapeProxy<'ctx, '_> {}
+
+impl<'ctx> TypedArrayLikeAccessor<'ctx, IntValue<'ctx>> for NDArrayShapeProxy<'ctx, '_> {
+    fn downcast_to_type(
+        &self,
+        _: &mut CodeGenContext<'ctx, '_>,
+        value: BasicValueEnum<'ctx>,
+    ) -> IntValue<'ctx> {
+        value.into_int_value()
+    }
+}
+
+impl<'ctx> TypedArrayLikeMutator<'ctx, IntValue<'ctx>> for NDArrayShapeProxy<'ctx, '_> {
+    fn upcast_from_type(
+        &self,
+        _: &mut CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> BasicValueEnum<'ctx> {
+        value.into()
+    }
+}
+
+/// Proxy type for accessing the `strides` array of an `NDArray` instance in LLVM.
+#[derive(Copy, Clone)]
+pub struct NDArrayStridesProxy<'ctx, 'a>(&'a NDArrayValue<'ctx>);
+
+impl<'ctx> ArrayLikeValue<'ctx> for NDArrayStridesProxy<'ctx, '_> {
+    fn element_type<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> AnyTypeEnum<'ctx> {
+        self.0.strides().base_ptr(ctx, generator).get_type().get_element_type()
+    }
+
+    fn base_ptr<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> PointerValue<'ctx> {
+        self.0.strides_field(ctx).get(ctx, self.0.as_base_value(), self.0.name)
+    }
+
+    fn size<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> IntValue<'ctx> {
+        self.0.load_ndims(ctx)
+    }
+}
+
+impl<'ctx> ArrayLikeIndexer<'ctx, IntValue<'ctx>> for NDArrayStridesProxy<'ctx, '_> {
+    unsafe fn ptr_offset_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let var_name = name.map(|v| format!("{v}.addr")).unwrap_or_default();
+
+        unsafe {
+            ctx.builder
+                .build_in_bounds_gep(self.base_ptr(ctx, generator), &[*idx], var_name.as_str())
+                .unwrap()
+        }
+    }
+
+    fn ptr_offset<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let size = self.size(ctx, generator);
+        let in_range = ctx.builder.build_int_compare(IntPredicate::ULT, *idx, size, "").unwrap();
+        ctx.make_assert(
+            generator,
+            in_range,
+            "0:IndexError",
+            "index {0} is out of bounds for axis 0 with size {1}",
+            [Some(*idx), Some(self.0.load_ndims(ctx)), None],
+            ctx.current_loc,
+        );
+
+        unsafe { self.ptr_offset_unchecked(ctx, generator, idx, name) }
+    }
+}
+
+impl<'ctx> UntypedArrayLikeAccessor<'ctx, IntValue<'ctx>> for NDArrayStridesProxy<'ctx, '_> {}
+impl<'ctx> UntypedArrayLikeMutator<'ctx, IntValue<'ctx>> for NDArrayStridesProxy<'ctx, '_> {}
+
+impl<'ctx> TypedArrayLikeAccessor<'ctx, IntValue<'ctx>> for NDArrayStridesProxy<'ctx, '_> {
+    fn downcast_to_type(
+        &self,
+        _: &mut CodeGenContext<'ctx, '_>,
+        value: BasicValueEnum<'ctx>,
+    ) -> IntValue<'ctx> {
+        value.into_int_value()
+    }
+}
+
+impl<'ctx> TypedArrayLikeMutator<'ctx, IntValue<'ctx>> for NDArrayStridesProxy<'ctx, '_> {
+    fn upcast_from_type(
+        &self,
+        _: &mut CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> BasicValueEnum<'ctx> {
+        value.into()
+    }
+}
+
+/// Proxy type for accessing the `data` array of an `NDArray` instance in LLVM.
+#[derive(Copy, Clone)]
+pub struct NDArrayDataProxy<'ctx, 'a>(&'a NDArrayValue<'ctx>);
+
+impl<'ctx> ArrayLikeValue<'ctx> for NDArrayDataProxy<'ctx, '_> {
+    fn element_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> AnyTypeEnum<'ctx> {
+        self.0.dtype.as_any_type_enum()
+    }
+
+    fn base_ptr<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        _: &G,
+    ) -> PointerValue<'ctx> {
+        self.0.data_field(ctx).get(ctx, self.0.as_base_value(), self.0.name)
+    }
+
+    fn size<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        generator: &G,
+    ) -> IntValue<'ctx> {
+        irrt::ndarray::call_ndarray_calc_size(
+            generator,
+            ctx,
+            &self.as_slice_value(ctx, generator),
+            (None, None),
+        )
+    }
+}
+
+impl<'ctx> ArrayLikeIndexer<'ctx> for NDArrayDataProxy<'ctx, '_> {
+    unsafe fn ptr_offset_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let sizeof_elem = ctx
+            .builder
+            .build_int_truncate_or_bit_cast(
+                self.element_type(ctx, generator).size_of().unwrap(),
+                idx.get_type(),
+                "",
+            )
+            .unwrap();
+        let idx = ctx.builder.build_int_mul(*idx, sizeof_elem, "").unwrap();
+        let ptr = unsafe {
+            ctx.builder
+                .build_in_bounds_gep(
+                    self.base_ptr(ctx, generator),
+                    &[idx],
+                    name.unwrap_or_default(),
+                )
+                .unwrap()
+        };
+
+        // Current implementation is transparent - The returned pointer type is
+        // already cast into the expected type, allowing for immediately
+        // load/store.
+        ctx.builder
+            .build_pointer_cast(
+                ptr,
+                BasicTypeEnum::try_from(self.element_type(ctx, generator))
+                    .unwrap()
+                    .ptr_type(AddressSpace::default()),
+                "",
+            )
+            .unwrap()
+    }
+
+    fn ptr_offset<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        idx: &IntValue<'ctx>,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let data_sz = self.size(ctx, generator);
+        let in_range = ctx.builder.build_int_compare(IntPredicate::ULT, *idx, data_sz, "").unwrap();
+        ctx.make_assert(
+            generator,
+            in_range,
+            "0:IndexError",
+            "index {0} is out of bounds with size {1}",
+            [Some(*idx), Some(self.0.load_ndims(ctx)), None],
+            ctx.current_loc,
+        );
+
+        let ptr = unsafe { self.ptr_offset_unchecked(ctx, generator, idx, name) };
+
+        // Current implementation is transparent - The returned pointer type is
+        // already cast into the expected type, allowing for immediately
+        // load/store.
+        ctx.builder
+            .build_pointer_cast(
+                ptr,
+                BasicTypeEnum::try_from(self.element_type(ctx, generator))
+                    .unwrap()
+                    .ptr_type(AddressSpace::default()),
+                "",
+            )
+            .unwrap()
+    }
+}
+
+impl<'ctx> UntypedArrayLikeAccessor<'ctx, IntValue<'ctx>> for NDArrayDataProxy<'ctx, '_> {}
+impl<'ctx> UntypedArrayLikeMutator<'ctx, IntValue<'ctx>> for NDArrayDataProxy<'ctx, '_> {}
+
+impl<'ctx, Index: UntypedArrayLikeAccessor<'ctx>> ArrayLikeIndexer<'ctx, Index>
+    for NDArrayDataProxy<'ctx, '_>
+{
+    unsafe fn ptr_offset_unchecked<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        indices: &Index,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let llvm_usize = generator.get_size_type(ctx.ctx);
+
+        let indices_elem_ty = indices
+            .ptr_offset(ctx, generator, &llvm_usize.const_zero(), None)
+            .get_type()
+            .get_element_type();
+        let Ok(indices_elem_ty) = IntType::try_from(indices_elem_ty) else {
+            panic!("Expected list[int32] but got {indices_elem_ty}")
+        };
+        assert_eq!(
+            indices_elem_ty.get_bit_width(),
+            32,
+            "Expected list[int32] but got list[int{}]",
+            indices_elem_ty.get_bit_width()
+        );
+
+        let index = irrt::ndarray::call_ndarray_flatten_index(generator, ctx, *self.0, indices);
+        let sizeof_elem = ctx
+            .builder
+            .build_int_truncate_or_bit_cast(
+                self.element_type(ctx, generator).size_of().unwrap(),
+                index.get_type(),
+                "",
+            )
+            .unwrap();
+        let index = ctx.builder.build_int_mul(index, sizeof_elem, "").unwrap();
+
+        let ptr = unsafe {
+            ctx.builder
+                .build_in_bounds_gep(
+                    self.base_ptr(ctx, generator),
+                    &[index],
+                    name.unwrap_or_default(),
+                )
+                .unwrap()
+        };
+        // TODO: Current implementation is transparent
+        ctx.builder
+            .build_pointer_cast(
+                ptr,
+                BasicTypeEnum::try_from(self.element_type(ctx, generator))
+                    .unwrap()
+                    .ptr_type(AddressSpace::default()),
+                "",
+            )
+            .unwrap()
+    }
+
+    fn ptr_offset<G: CodeGenerator + ?Sized>(
+        &self,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut G,
+        indices: &Index,
+        name: Option<&str>,
+    ) -> PointerValue<'ctx> {
+        let llvm_usize = generator.get_size_type(ctx.ctx);
+
+        let indices_size = indices.size(ctx, generator);
+        let nidx_leq_ndims = ctx
+            .builder
+            .build_int_compare(IntPredicate::SLE, indices_size, self.0.load_ndims(ctx), "")
+            .unwrap();
+        ctx.make_assert(
+            generator,
+            nidx_leq_ndims,
+            "0:IndexError",
+            "invalid index to scalar variable",
+            [None, None, None],
+            ctx.current_loc,
+        );
+
+        let indices_len = indices.size(ctx, generator);
+        let ndarray_len = self.0.load_ndims(ctx);
+        let len = call_int_umin(ctx, indices_len, ndarray_len, None);
+        gen_for_callback_incrementing(
+            generator,
+            ctx,
+            None,
+            llvm_usize.const_zero(),
+            (len, false),
+            |generator, ctx, _, i| {
+                let (dim_idx, dim_sz) = unsafe {
+                    (
+                        indices.get_unchecked(ctx, generator, &i, None).into_int_value(),
+                        self.0.shape().get_typed_unchecked(ctx, generator, &i, None),
+                    )
+                };
+                let dim_idx = ctx
+                    .builder
+                    .build_int_z_extend_or_bit_cast(dim_idx, dim_sz.get_type(), "")
+                    .unwrap();
+
+                let dim_lt =
+                    ctx.builder.build_int_compare(IntPredicate::SLT, dim_idx, dim_sz, "").unwrap();
+
+                ctx.make_assert(
+                    generator,
+                    dim_lt,
+                    "0:IndexError",
+                    "index {0} is out of bounds for axis 0 with size {1}",
+                    [Some(dim_idx), Some(dim_sz), None],
+                    ctx.current_loc,
+                );
+
+                Ok(())
+            },
+            llvm_usize.const_int(1, false),
+        )
+        .unwrap();
+
+        let ptr = unsafe { self.ptr_offset_unchecked(ctx, generator, indices, name) };
+        // TODO: Current implementation is transparent
+        ctx.builder
+            .build_pointer_cast(
+                ptr,
+                BasicTypeEnum::try_from(self.element_type(ctx, generator))
+                    .unwrap()
+                    .ptr_type(AddressSpace::default()),
+                "",
+            )
+            .unwrap()
+    }
+}
+
+impl<'ctx, Index: UntypedArrayLikeAccessor<'ctx>> UntypedArrayLikeAccessor<'ctx, Index>
+    for NDArrayDataProxy<'ctx, '_>
+{
+}
+impl<'ctx, Index: UntypedArrayLikeAccessor<'ctx>> UntypedArrayLikeMutator<'ctx, Index>
+    for NDArrayDataProxy<'ctx, '_>
+{
+}
+
+/// A version of [`call_nac3_ndarray_set_strides_by_shape`] in Rust.
+///
+/// This function is used generating strides for globally defined contiguous ndarrays.
+#[must_use]
+pub fn make_contiguous_strides(itemsize: u64, ndims: u64, shape: &[u64]) -> Vec<u64> {
+    let mut strides = Vec::with_capacity(ndims as usize);
+    let mut stride_product = 1u64;
+    for i in 0..ndims {
+        let axis = ndims - i - 1;
+        strides[axis as usize] = stride_product * itemsize;
+        stride_product *= shape[axis as usize];
+    }
+    strides
+}
+
+/// A convenience enum for implementing functions that acts on scalars or ndarrays or both.
+#[derive(Clone, Copy)]
+pub enum ScalarOrNDArray<'ctx> {
+    Scalar(BasicValueEnum<'ctx>),
+    NDArray(NDArrayValue<'ctx>),
+}
+
+impl<'ctx> ScalarOrNDArray<'ctx> {
+    /// Get the underlying [`BasicValueEnum<'ctx>`] of this [`ScalarOrNDArray`].
+    #[must_use]
+    pub fn to_basic_value_enum(self) -> BasicValueEnum<'ctx> {
+        match self {
+            ScalarOrNDArray::Scalar(scalar) => scalar,
+            ScalarOrNDArray::NDArray(ndarray) => ndarray.as_base_value().into(),
+        }
+    }
+}

nac3core/src/codegen/values/ndarray/nditer.rs

@@ -0,0 +1,176 @@
+use inkwell::{
+    types::{BasicType, IntType},
+    values::{BasicValueEnum, IntValue, PointerValue},
+    AddressSpace,
+};
+
+use super::{NDArrayValue, ProxyValue, TypedArrayLikeAccessor, TypedArrayLikeMutator};
+use crate::codegen::{
+    irrt,
+    stmt::{gen_for_callback, BreakContinueHooks},
+    types::{ndarray::NDIterType, structure::StructField},
+    values::{ArraySliceValue, TypedArrayLikeAdapter},
+    CodeGenContext, CodeGenerator,
+};
+
+#[derive(Copy, Clone)]
+pub struct NDIterValue<'ctx> {
+    value: PointerValue<'ctx>,
+    parent: NDArrayValue<'ctx>,
+    indices: ArraySliceValue<'ctx>,
+    llvm_usize: IntType<'ctx>,
+    name: Option<&'ctx str>,
+}
+
+impl<'ctx> NDIterValue<'ctx> {
+    /// Checks whether `value` is an instance of `NDArray`, returning [Err] if `value` is not an
+    /// instance.
+    pub fn is_representable(
+        value: PointerValue<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        <Self as ProxyValue>::Type::is_representable(value.get_type(), llvm_usize)
+    }
+
+    /// Creates an [`NDArrayValue`] from a [`PointerValue`].
+    #[must_use]
+    pub fn from_pointer_value(
+        ptr: PointerValue<'ctx>,
+        parent: NDArrayValue<'ctx>,
+        indices: ArraySliceValue<'ctx>,
+        llvm_usize: IntType<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> Self {
+        debug_assert!(Self::is_representable(ptr, llvm_usize).is_ok());
+
+        Self { value: ptr, parent, indices, llvm_usize, name }
+    }
+
+    /// Is the current iteration valid?
+    ///
+    /// If true, then `element`, `indices` and `nth` contain details about the current element.
+    ///
+    /// If `ndarray` is unsized, this returns true only for the first iteration.
+    /// If `ndarray` is 0-sized, this always returns false.
+    #[must_use]
+    pub fn has_element<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) -> IntValue<'ctx> {
+        irrt::ndarray::call_nac3_nditer_has_element(generator, ctx, *self)
+    }
+
+    /// Go to the next element. If `has_element()` is false, then this has undefined behavior.
+    ///
+    /// If `ndarray` is unsized, this can only be called once.
+    /// If `ndarray` is 0-sized, this can never be called.
+    pub fn next<G: CodeGenerator + ?Sized>(&self, generator: &G, ctx: &CodeGenContext<'ctx, '_>) {
+        irrt::ndarray::call_nac3_nditer_next(generator, ctx, *self);
+    }
+
+    fn element(&self, ctx: &CodeGenContext<'ctx, '_>) -> StructField<'ctx, PointerValue<'ctx>> {
+        self.get_type().get_fields(ctx.ctx).element
+    }
+
+    /// Get pointer to the current element.
+    #[must_use]
+    pub fn get_pointer(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        let elem_ty = self.parent.dtype;
+
+        let p = self.element(ctx).get(ctx, self.as_base_value(), None);
+        ctx.builder
+            .build_pointer_cast(p, elem_ty.ptr_type(AddressSpace::default()), "element")
+            .unwrap()
+    }
+
+    /// Get the value of the current element.
+    #[must_use]
+    pub fn get_scalar(&self, ctx: &CodeGenContext<'ctx, '_>) -> BasicValueEnum<'ctx> {
+        let p = self.get_pointer(ctx);
+        ctx.builder.build_load(p, "value").unwrap()
+    }
+
+    fn nth(&self, ctx: &CodeGenContext<'ctx, '_>) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields(ctx.ctx).nth
+    }
+
+    /// Get the index of the current element if this ndarray were a flat ndarray.
+    #[must_use]
+    pub fn get_index(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        self.nth(ctx).get(ctx, self.as_base_value(), None)
+    }
+
+    /// Get the indices of the current element.
+    #[must_use]
+    pub fn get_indices(
+        &'ctx self,
+    ) -> impl TypedArrayLikeAccessor<'ctx, IntValue<'ctx>> + TypedArrayLikeMutator<'ctx, IntValue<'ctx>>
+    {
+        TypedArrayLikeAdapter::from(
+            self.indices,
+            Box::new(|ctx, val| {
+                ctx.builder
+                    .build_int_z_extend_or_bit_cast(val.into_int_value(), self.llvm_usize, "")
+                    .unwrap()
+            }),
+            Box::new(|_, val| val.into()),
+        )
+    }
+}
+
+impl<'ctx> ProxyValue<'ctx> for NDIterValue<'ctx> {
+    type Base = PointerValue<'ctx>;
+    type Type = NDIterType<'ctx>;
+
+    fn get_type(&self) -> Self::Type {
+        NDIterType::from_type(self.as_base_value().get_type(), self.llvm_usize)
+    }
+
+    fn as_base_value(&self) -> Self::Base {
+        self.value
+    }
+}
+
+impl<'ctx> From<NDIterValue<'ctx>> for PointerValue<'ctx> {
+    fn from(value: NDIterValue<'ctx>) -> Self {
+        value.as_base_value()
+    }
+}
+
+impl<'ctx> NDArrayValue<'ctx> {
+    /// Iterate through every element in the ndarray.
+    ///
+    /// `body` has access to [`BreakContinueHooks`] to short-circuit and [`NDIterValue`] to
+    /// get properties of the current iteration (e.g., the current element, indices, etc.)
+    pub fn foreach<'a, G, F>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, 'a>,
+        body: F,
+    ) -> Result<(), String>
+    where
+        G: CodeGenerator + ?Sized,
+        F: FnOnce(
+            &mut G,
+            &mut CodeGenContext<'ctx, 'a>,
+            BreakContinueHooks<'ctx>,
+            NDIterValue<'ctx>,
+        ) -> Result<(), String>,
+    {
+        gen_for_callback(
+            generator,
+            ctx,
+            Some("ndarray_foreach"),
+            |generator, ctx| {
+                Ok(NDIterType::new(generator, ctx.ctx).construct(generator, ctx, *self))
+            },
+            |generator, ctx, nditer| Ok(nditer.has_element(generator, ctx)),
+            |generator, ctx, hooks, nditer| body(generator, ctx, hooks, nditer),
+            |generator, ctx, nditer| {
+                nditer.next(generator, ctx);
+                Ok(())
+            },
+        )
+    }
+}

nac3core/src/codegen/values/ndarray/view.rs

@@ -0,0 +1,36 @@
+use std::iter::{once, repeat_n};
+
+use itertools::Itertools;
+
+use crate::codegen::{
+    values::ndarray::{NDArrayValue, RustNDIndex},
+    CodeGenContext, CodeGenerator,
+};
+
+impl<'ctx> NDArrayValue<'ctx> {
+    /// Make sure the ndarray is at least `ndmin`-dimensional.
+    ///
+    /// If this ndarray's `ndims` is less than `ndmin`, a view is created on this with 1s prepended
+    /// to the shape. Otherwise, this function does nothing and return this ndarray.
+    #[must_use]
+    pub fn atleast_nd<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        ndmin: u64,
+    ) -> Self {
+        assert!(self.ndims.is_some(), "NDArrayValue::atleast_nd is only supported for instances with compile-time known ndims (self.ndims = Some(...))");
+
+        let ndims = self.ndims.unwrap();
+
+        if ndims < ndmin {
+            // Extend the dimensions with np.newaxis.
+            let indices = repeat_n(RustNDIndex::NewAxis, (ndmin - ndims) as usize)
+                .chain(once(RustNDIndex::Ellipsis))
+                .collect_vec();
+            self.index(generator, ctx, &indices)
+        } else {
+            *self
+        }
+    }
+}

nac3core/src/codegen/values/range.rs

@@ -0,0 +1,153 @@
+use inkwell::values::{BasicValueEnum, IntValue, PointerValue};
+
+use super::ProxyValue;
+use crate::codegen::{types::RangeType, CodeGenContext};
+
+/// Proxy type for accessing a `range` value in LLVM.
+#[derive(Copy, Clone)]
+pub struct RangeValue<'ctx> {
+    value: PointerValue<'ctx>,
+    name: Option<&'ctx str>,
+}
+
+impl<'ctx> RangeValue<'ctx> {
+    /// Checks whether `value` is an instance of `range`, returning [Err] if `value` is not an instance.
+    pub fn is_representable(value: PointerValue<'ctx>) -> Result<(), String> {
+        RangeType::is_representable(value.get_type())
+    }
+
+    /// Creates an [`RangeValue`] from a [`PointerValue`].
+    #[must_use]
+    pub fn from_pointer_value(ptr: PointerValue<'ctx>, name: Option<&'ctx str>) -> Self {
+        debug_assert!(Self::is_representable(ptr).is_ok());
+
+        RangeValue { value: ptr, name }
+    }
+
+    fn ptr_to_start(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        let llvm_i32 = ctx.ctx.i32_type();
+        let var_name = self.name.map(|v| format!("{v}.start.addr")).unwrap_or_default();
+
+        unsafe {
+            ctx.builder
+                .build_in_bounds_gep(
+                    self.as_base_value(),
+                    &[llvm_i32.const_zero(), llvm_i32.const_int(0, false)],
+                    var_name.as_str(),
+                )
+                .unwrap()
+        }
+    }
+
+    fn ptr_to_end(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        let llvm_i32 = ctx.ctx.i32_type();
+        let var_name = self.name.map(|v| format!("{v}.end.addr")).unwrap_or_default();
+
+        unsafe {
+            ctx.builder
+                .build_in_bounds_gep(
+                    self.as_base_value(),
+                    &[llvm_i32.const_zero(), llvm_i32.const_int(1, false)],
+                    var_name.as_str(),
+                )
+                .unwrap()
+        }
+    }
+
+    fn ptr_to_step(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+        let llvm_i32 = ctx.ctx.i32_type();
+        let var_name = self.name.map(|v| format!("{v}.step.addr")).unwrap_or_default();
+
+        unsafe {
+            ctx.builder
+                .build_in_bounds_gep(
+                    self.as_base_value(),
+                    &[llvm_i32.const_zero(), llvm_i32.const_int(2, false)],
+                    var_name.as_str(),
+                )
+                .unwrap()
+        }
+    }
+
+    /// Stores the `start` value into this instance.
+    pub fn store_start(&self, ctx: &CodeGenContext<'ctx, '_>, start: IntValue<'ctx>) {
+        debug_assert_eq!(start.get_type().get_bit_width(), 32);
+
+        let pstart = self.ptr_to_start(ctx);
+        ctx.builder.build_store(pstart, start).unwrap();
+    }
+
+    /// Returns the `start` value of this `range`.
+    pub fn load_start(&self, ctx: &CodeGenContext<'ctx, '_>, name: Option<&str>) -> IntValue<'ctx> {
+        let pstart = self.ptr_to_start(ctx);
+        let var_name = name
+            .map(ToString::to_string)
+            .or_else(|| self.name.map(|v| format!("{v}.start")))
+            .unwrap_or_default();
+
+        ctx.builder
+            .build_load(pstart, var_name.as_str())
+            .map(BasicValueEnum::into_int_value)
+            .unwrap()
+    }
+
+    /// Stores the `end` value into this instance.
+    pub fn store_end(&self, ctx: &CodeGenContext<'ctx, '_>, end: IntValue<'ctx>) {
+        debug_assert_eq!(end.get_type().get_bit_width(), 32);
+
+        let pend = self.ptr_to_end(ctx);
+        ctx.builder.build_store(pend, end).unwrap();
+    }
+
+    /// Returns the `end` value of this `range`.
+    pub fn load_end(&self, ctx: &CodeGenContext<'ctx, '_>, name: Option<&str>) -> IntValue<'ctx> {
+        let pend = self.ptr_to_end(ctx);
+        let var_name = name
+            .map(ToString::to_string)
+            .or_else(|| self.name.map(|v| format!("{v}.end")))
+            .unwrap_or_default();
+
+        ctx.builder.build_load(pend, var_name.as_str()).map(BasicValueEnum::into_int_value).unwrap()
+    }
+
+    /// Stores the `step` value into this instance.
+    pub fn store_step(&self, ctx: &CodeGenContext<'ctx, '_>, step: IntValue<'ctx>) {
+        debug_assert_eq!(step.get_type().get_bit_width(), 32);
+
+        let pstep = self.ptr_to_step(ctx);
+        ctx.builder.build_store(pstep, step).unwrap();
+    }
+
+    /// Returns the `step` value of this `range`.
+    pub fn load_step(&self, ctx: &CodeGenContext<'ctx, '_>, name: Option<&str>) -> IntValue<'ctx> {
+        let pstep = self.ptr_to_step(ctx);
+        let var_name = name
+            .map(ToString::to_string)
+            .or_else(|| self.name.map(|v| format!("{v}.step")))
+            .unwrap_or_default();
+
+        ctx.builder
+            .build_load(pstep, var_name.as_str())
+            .map(BasicValueEnum::into_int_value)
+            .unwrap()
+    }
+}
+
+impl<'ctx> ProxyValue<'ctx> for RangeValue<'ctx> {
+    type Base = PointerValue<'ctx>;
+    type Type = RangeType<'ctx>;
+
+    fn get_type(&self) -> Self::Type {
+        RangeType::from_type(self.value.get_type())
+    }
+
+    fn as_base_value(&self) -> Self::Base {
+        self.value
+    }
+}
+
+impl<'ctx> From<RangeValue<'ctx>> for PointerValue<'ctx> {
+    fn from(value: RangeValue<'ctx>) -> Self {
+        value.as_base_value()
+    }
+}

nac3core/src/codegen/values/utils/mod.rs

@@ -0,0 +1,3 @@
+pub use slice::*;
+
+mod slice;

nac3core/src/codegen/values/utils/slice.rs

@@ -0,0 +1,231 @@
+use inkwell::{
+    types::IntType,
+    values::{IntValue, PointerValue},
+};
+
+use nac3parser::ast::Expr;
+
+use crate::{
+    codegen::{
+        types::{structure::StructField, utils::SliceType},
+        values::ProxyValue,
+        CodeGenContext, CodeGenerator,
+    },
+    typecheck::typedef::Type,
+};
+
+/// An IRRT representation of an (unresolved) slice.
+#[derive(Copy, Clone)]
+pub struct SliceValue<'ctx> {
+    value: PointerValue<'ctx>,
+    int_ty: IntType<'ctx>,
+    llvm_usize: IntType<'ctx>,
+    name: Option<&'ctx str>,
+}
+
+impl<'ctx> SliceValue<'ctx> {
+    /// Checks whether `value` is an instance of `ContiguousNDArray`, returning [Err] if `value` is
+    /// not an instance.
+    pub fn is_representable(
+        value: PointerValue<'ctx>,
+        llvm_usize: IntType<'ctx>,
+    ) -> Result<(), String> {
+        <Self as ProxyValue<'ctx>>::Type::is_representable(value.get_type(), llvm_usize)
+    }
+
+    /// Creates an [`SliceValue`] from a [`PointerValue`].
+    #[must_use]
+    pub fn from_pointer_value(
+        ptr: PointerValue<'ctx>,
+        int_ty: IntType<'ctx>,
+        llvm_usize: IntType<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> Self {
+        debug_assert!(Self::is_representable(ptr, llvm_usize).is_ok());
+
+        Self { value: ptr, int_ty, llvm_usize, name }
+    }
+
+    fn start_defined_field(&self) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields().start_defined
+    }
+
+    pub fn load_start_defined(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        self.start_defined_field().get(ctx, self.value, self.name)
+    }
+
+    fn start_field(&self) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields().start
+    }
+
+    pub fn load_start(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        self.start_field().get(ctx, self.value, self.name)
+    }
+
+    pub fn store_start(&self, ctx: &CodeGenContext<'ctx, '_>, value: Option<IntValue<'ctx>>) {
+        match value {
+            Some(start) => {
+                self.start_defined_field().set(
+                    ctx,
+                    self.value,
+                    ctx.ctx.bool_type().const_all_ones(),
+                    self.name,
+                );
+                self.start_field().set(ctx, self.value, start, self.name);
+            }
+
+            None => self.start_defined_field().set(
+                ctx,
+                self.value,
+                ctx.ctx.bool_type().const_zero(),
+                self.name,
+            ),
+        }
+    }
+
+    fn stop_defined_field(&self) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields().stop_defined
+    }
+
+    pub fn load_stop_defined(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        self.stop_defined_field().get(ctx, self.value, self.name)
+    }
+
+    fn stop_field(&self) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields().stop
+    }
+
+    pub fn load_stop(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        self.stop_field().get(ctx, self.value, self.name)
+    }
+
+    pub fn store_stop(&self, ctx: &CodeGenContext<'ctx, '_>, value: Option<IntValue<'ctx>>) {
+        match value {
+            Some(stop) => {
+                self.stop_defined_field().set(
+                    ctx,
+                    self.value,
+                    ctx.ctx.bool_type().const_all_ones(),
+                    self.name,
+                );
+                self.stop_field().set(ctx, self.value, stop, self.name);
+            }
+
+            None => self.stop_defined_field().set(
+                ctx,
+                self.value,
+                ctx.ctx.bool_type().const_zero(),
+                self.name,
+            ),
+        }
+    }
+
+    fn step_defined_field(&self) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields().step_defined
+    }
+
+    pub fn load_step_defined(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        self.step_defined_field().get(ctx, self.value, self.name)
+    }
+
+    fn step_field(&self) -> StructField<'ctx, IntValue<'ctx>> {
+        self.get_type().get_fields().step
+    }
+
+    pub fn load_step(&self, ctx: &CodeGenContext<'ctx, '_>) -> IntValue<'ctx> {
+        self.step_field().get(ctx, self.value, self.name)
+    }
+
+    pub fn store_step(&self, ctx: &CodeGenContext<'ctx, '_>, value: Option<IntValue<'ctx>>) {
+        match value {
+            Some(step) => {
+                self.step_defined_field().set(
+                    ctx,
+                    self.value,
+                    ctx.ctx.bool_type().const_all_ones(),
+                    self.name,
+                );
+                self.step_field().set(ctx, self.value, step, self.name);
+            }
+
+            None => self.step_defined_field().set(
+                ctx,
+                self.value,
+                ctx.ctx.bool_type().const_zero(),
+                self.name,
+            ),
+        }
+    }
+}
+
+impl<'ctx> ProxyValue<'ctx> for SliceValue<'ctx> {
+    type Base = PointerValue<'ctx>;
+    type Type = SliceType<'ctx>;
+
+    fn get_type(&self) -> Self::Type {
+        Self::Type::from_type(self.value.get_type(), self.int_ty, self.llvm_usize)
+    }
+
+    fn as_base_value(&self) -> Self::Base {
+        self.value
+    }
+}
+
+impl<'ctx> From<SliceValue<'ctx>> for PointerValue<'ctx> {
+    fn from(value: SliceValue<'ctx>) -> Self {
+        value.as_base_value()
+    }
+}
+
+/// A slice represented in compile-time by `start`, `stop` and `step`, all held as LLVM values.
+// TODO: Rename this to CTConstSlice
+#[derive(Debug, Copy, Clone)]
+pub struct RustSlice<'ctx> {
+    int_ty: IntType<'ctx>,
+    start: Option<IntValue<'ctx>>,
+    stop: Option<IntValue<'ctx>>,
+    step: Option<IntValue<'ctx>>,
+}
+
+impl<'ctx> RustSlice<'ctx> {
+    /// Generate LLVM IR for an [`ExprKind::Slice`] and convert it into a [`RustSlice`].
+    #[allow(clippy::type_complexity)]
+    pub fn from_slice_expr<G: CodeGenerator>(
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        lower: &Option<Box<Expr<Option<Type>>>>,
+        upper: &Option<Box<Expr<Option<Type>>>>,
+        step: &Option<Box<Expr<Option<Type>>>>,
+    ) -> Result<RustSlice<'ctx>, String> {
+        let mut value_mapper = |value_expr: &Option<Box<Expr<Option<Type>>>>| -> Result<_, String> {
+            Ok(match value_expr {
+                None => None,
+                Some(value_expr) => {
+                    let value_expr = generator
+                        .gen_expr(ctx, value_expr)?
+                        .map(|value| {
+                            value.to_basic_value_enum(ctx, generator, ctx.primitives.int32)
+                        })
+                        .unwrap()?;
+
+                    Some(value_expr.into_int_value())
+                }
+            })
+        };
+
+        let start = value_mapper(lower)?;
+        let stop = value_mapper(upper)?;
+        let step = value_mapper(step)?;
+
+        Ok(RustSlice { int_ty: ctx.ctx.i32_type(), start, stop, step })
+    }
+
+    /// Write the contents to an LLVM [`SliceValue`].
+    pub fn write_to_slice(&self, ctx: &CodeGenContext<'ctx, '_>, dst_slice_ptr: SliceValue<'ctx>) {
+        assert_eq!(self.int_ty, dst_slice_ptr.int_ty);
+
+        dst_slice_ptr.store_start(ctx, self.start);
+        dst_slice_ptr.store_stop(ctx, self.stop);
+        dst_slice_ptr.store_step(ctx, self.step);
+    }
+}

nac3core/src/lib.rs

@@ -1,10 +1,4 @@
-#![deny(
+#![deny(future_incompatible, let_underscore, nonstandard_style, clippy::all)]
-    future_incompatible,
-    let_underscore,
-    nonstandard_style,
-    rust_2024_compatibility,
-    clippy::all
-)]
 #![warn(clippy::pedantic)]
 #![allow(
     dead_code,
@@ -19,7 +13,13 @@
     clippy::wildcard_imports
 )]
 
+// users of nac3core need to use the same version of these dependencies, so expose them as nac3core::*
+pub use inkwell;
+pub use nac3parser;
+
 pub mod codegen;
 pub mod symbol_resolver;
 pub mod toplevel;
 pub mod typecheck;
+
+extern crate self as nac3core;

nac3core/src/symbol_resolver.rs

@@ -1,7 +1,15 @@
-use std::fmt::Debug;
+use std::{
-use std::rc::Rc;
+    collections::{HashMap, HashSet},
-use std::sync::Arc;
+    fmt::{Debug, Display},
-use std::{collections::HashMap, collections::HashSet, fmt::Display};
+    rc::Rc,
+    sync::Arc,
+};
+
+use inkwell::values::{BasicValueEnum, FloatValue, IntValue, PointerValue, StructValue};
+use itertools::{chain, izip, Itertools};
+use parking_lot::RwLock;
+
+use nac3parser::ast::{Constant, Expr, Location, StrRef};
 
 use crate::{
     codegen::{CodeGenContext, CodeGenerator},
@@ -11,10 +19,6 @@ use crate::{
         typedef::{Type, TypeEnum, Unifier, VarMap},
     },
 };
-use inkwell::values::{BasicValueEnum, FloatValue, IntValue, PointerValue, StructValue};
-use itertools::{chain, izip, Itertools};
-use nac3parser::ast::{Constant, Expr, Location, StrRef};
-use parking_lot::RwLock;
 
 #[derive(Clone, PartialEq, Debug)]
 pub enum SymbolValue {
@@ -365,6 +369,7 @@ pub trait SymbolResolver {
         &self,
         str: StrRef,
         ctx: &mut CodeGenContext<'ctx, '_>,
+        generator: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>>;
 
     fn get_default_param_value(&self, expr: &Expr) -> Option<SymbolValue>;

nac3core/src/toplevel/builtins.rs

@@ -1,6 +1,5 @@
 use std::iter::once;
 
-use helper::{debug_assert_prim_is_allowed, make_exception_fields, PrimDefDetails};
 use indexmap::IndexMap;
 use inkwell::{
     attributes::{Attribute, AttributeLoc},
@@ -11,20 +10,22 @@ use inkwell::{
 use itertools::Either;
 use strum::IntoEnumIterator;
 
+use super::{
+    helper::{debug_assert_prim_is_allowed, make_exception_fields, PrimDef, PrimDefDetails},
+    numpy::make_ndarray_ty,
+    *,
+};
 use crate::{
     codegen::{
         builtin_fns,
-        classes::{ProxyValue, RangeValue},
         numpy::*,
         stmt::exn_constructor,
+        values::{ProxyValue, RangeValue},
     },
     symbol_resolver::SymbolValue,
-    toplevel::{helper::PrimDef, numpy::make_ndarray_ty},
     typecheck::typedef::{into_var_map, iter_type_vars, TypeVar, VarMap},
 };
 
-use super::*;
-
 type BuiltinInfo = Vec<(Arc<RwLock<TopLevelDef>>, Option<Stmt>)>;
 
 pub fn get_exn_constructor(
@@ -709,7 +710,7 @@ impl<'a> BuiltinBuilder<'a> {
                         let (zelf_ty, zelf) = obj.unwrap();
                         let zelf =
                             zelf.to_basic_value_enum(ctx, generator, zelf_ty)?.into_pointer_value();
-                        let zelf = RangeValue::from_ptr_val(zelf, Some("range"));
+                        let zelf = RangeValue::from_pointer_value(zelf, Some("range"));
 
                         let mut start = None;
                         let mut stop = None;

nac3core/src/toplevel/helper.rs

@@ -1,13 +1,15 @@
 use std::convert::TryInto;
 
-use crate::symbol_resolver::SymbolValue;
-use crate::toplevel::numpy::unpack_ndarray_var_tys;
-use crate::typecheck::typedef::{into_var_map, iter_type_vars, Mapping, TypeVarId, VarMap};
-use nac3parser::ast::{Constant, Location};
 use strum::IntoEnumIterator;
 use strum_macros::EnumIter;
 
-use super::*;
+use nac3parser::ast::{Constant, ExprKind, Location};
+
+use super::{numpy::unpack_ndarray_var_tys, *};
+use crate::{
+    symbol_resolver::SymbolValue,
+    typecheck::typedef::{into_var_map, iter_type_vars, Mapping, TypeVarId, VarMap},
+};
 
 /// All primitive types and functions in nac3core.
 #[derive(Clone, Copy, Debug, EnumIter, PartialEq, Eq)]
@@ -387,6 +389,9 @@ impl TopLevelDef {
                     r
                 }
             ),
+            TopLevelDef::Variable { name, ty, .. } => {
+                format!("Variable {{ name: {name:?}, ty: {:?} }}", unifier.stringify(*ty),)
+            }
         }
     }
 }
@@ -588,6 +593,18 @@ impl TopLevelComposer {
         }
     }
 
+    #[must_use]
+    pub fn make_top_level_variable_def(
+        name: String,
+        simple_name: StrRef,
+        ty: Type,
+        ty_decl: Option<Expr>,
+        resolver: Option<Arc<dyn SymbolResolver + Send + Sync>>,
+        loc: Option<Location>,
+    ) -> TopLevelDef {
+        TopLevelDef::Variable { name, simple_name, ty, ty_decl, resolver, loc }
+    }
+
     #[must_use]
     pub fn make_class_method_name(mut class_name: String, method_name: &str) -> String {
         class_name.push('.');
@@ -607,64 +624,6 @@ impl TopLevelComposer {
         Err(HashSet::from([format!("no method {method_name} in the current class")]))
     }
 
-    /// get all base class def id of a class, excluding itself. \
-    /// this function should called only after the direct parent is set
-    /// and before all the ancestors are set
-    /// and when we allow single inheritance \
-    /// the order of the returned list is from the child to the deepest ancestor
-    pub fn get_all_ancestors_helper(
-        child: &TypeAnnotation,
-        temp_def_list: &[Arc<RwLock<TopLevelDef>>],
-    ) -> Result<Vec<TypeAnnotation>, HashSet<String>> {
-        let mut result: Vec<TypeAnnotation> = Vec::new();
-        let mut parent = Self::get_parent(child, temp_def_list);
-        while let Some(p) = parent {
-            parent = Self::get_parent(&p, temp_def_list);
-            let p_id = if let TypeAnnotation::CustomClass { id, .. } = &p {
-                *id
-            } else {
-                unreachable!("must be class kind annotation")
-            };
-            // check cycle
-            let no_cycle = result.iter().all(|x| {
-                let TypeAnnotation::CustomClass { id, .. } = x else {
-                    unreachable!("must be class kind annotation")
-                };
-
-                id.0 != p_id.0
-            });
-            if no_cycle {
-                result.push(p);
-            } else {
-                return Err(HashSet::from(["cyclic inheritance detected".into()]));
-            }
-        }
-        Ok(result)
-    }
-
-    /// should only be called when finding all ancestors, so panic when wrong
-    fn get_parent(
-        child: &TypeAnnotation,
-        temp_def_list: &[Arc<RwLock<TopLevelDef>>],
-    ) -> Option<TypeAnnotation> {
-        let child_id = if let TypeAnnotation::CustomClass { id, .. } = child {
-            *id
-        } else {
-            unreachable!("should be class type annotation")
-        };
-        let child_def = temp_def_list.get(child_id.0).unwrap();
-        let child_def = child_def.read();
-        let TopLevelDef::Class { ancestors, .. } = &*child_def else {
-            unreachable!("child must be top level class def")
-        };
-
-        if ancestors.is_empty() {
-            None
-        } else {
-            Some(ancestors[0].clone())
-        }
-    }
-
     /// get the `var_id` of a given `TVar` type
     pub fn get_var_id(var_ty: Type, unifier: &mut Unifier) -> Result<TypeVarId, HashSet<String>> {
         if let TypeEnum::TVar { id, .. } = unifier.get_ty(var_ty).as_ref() {
@@ -733,7 +692,16 @@ impl TopLevelComposer {
         )
     }
 
-    pub fn get_all_assigned_field(stmts: &[Stmt<()>]) -> Result<HashSet<StrRef>, HashSet<String>> {
+    /// This function returns the fields that have been initialized in the `__init__` function of a class
+    /// The function takes as input:
+    ///  * `class_id`: The `object_id` of the class whose function is being evaluated (check `TopLevelDef::Class`)
+    ///  * `definition_ast_list`: A list of ast definitions and statements defined in `TopLevelComposer`
+    ///  * `stmts`: The body of function being parsed. Each statment is analyzed to check varaible initialization statements
+    pub fn get_all_assigned_field(
+        class_id: usize,
+        definition_ast_list: &Vec<DefAst>,
+        stmts: &[Stmt<()>],
+    ) -> Result<HashSet<StrRef>, HashSet<String>> {
         let mut result = HashSet::new();
         for s in stmts {
             match &s.node {
@@ -769,30 +737,138 @@ impl TopLevelComposer {
                 // TODO: do not check for For and While?
                 ast::StmtKind::For { body, orelse, .. }
                 | ast::StmtKind::While { body, orelse, .. } => {
-                    result.extend(Self::get_all_assigned_field(body.as_slice())?);
+                    result.extend(Self::get_all_assigned_field(
-                    result.extend(Self::get_all_assigned_field(orelse.as_slice())?);
+                        class_id,
+                        definition_ast_list,
+                        body.as_slice(),
+                    )?);
+                    result.extend(Self::get_all_assigned_field(
+                        class_id,
+                        definition_ast_list,
+                        orelse.as_slice(),
+                    )?);
                 }
                 ast::StmtKind::If { body, orelse, .. } => {
-                    let inited_for_sure = Self::get_all_assigned_field(body.as_slice())?
+                    let inited_for_sure = Self::get_all_assigned_field(
-                        .intersection(&Self::get_all_assigned_field(orelse.as_slice())?)
+                        class_id,
-                        .copied()
+                        definition_ast_list,
-                        .collect::<HashSet<_>>();
+                        body.as_slice(),
+                    )?
+                    .intersection(&Self::get_all_assigned_field(
+                        class_id,
+                        definition_ast_list,
+                        orelse.as_slice(),
+                    )?)
+                    .copied()
+                    .collect::<HashSet<_>>();
                     result.extend(inited_for_sure);
                 }
                 ast::StmtKind::Try { body, orelse, finalbody, .. } => {
-                    let inited_for_sure = Self::get_all_assigned_field(body.as_slice())?
+                    let inited_for_sure = Self::get_all_assigned_field(
-                        .intersection(&Self::get_all_assigned_field(orelse.as_slice())?)
+                        class_id,
-                        .copied()
+                        definition_ast_list,
-                        .collect::<HashSet<_>>();
+                        body.as_slice(),
+                    )?
+                    .intersection(&Self::get_all_assigned_field(
+                        class_id,
+                        definition_ast_list,
+                        orelse.as_slice(),
+                    )?)
+                    .copied()
+                    .collect::<HashSet<_>>();
                     result.extend(inited_for_sure);
-                    result.extend(Self::get_all_assigned_field(finalbody.as_slice())?);
+                    result.extend(Self::get_all_assigned_field(
+                        class_id,
+                        definition_ast_list,
+                        finalbody.as_slice(),
+                    )?);
                 }
                 ast::StmtKind::With { body, .. } => {
-                    result.extend(Self::get_all_assigned_field(body.as_slice())?);
+                    result.extend(Self::get_all_assigned_field(
+                        class_id,
+                        definition_ast_list,
+                        body.as_slice(),
+                    )?);
+                }
+                // Variables Initialized in function calls
+                ast::StmtKind::Expr { value, .. } => {
+                    let ExprKind::Call { func, .. } = &value.node else {
+                        continue;
+                    };
+                    let ExprKind::Attribute { value, attr, .. } = &func.node else {
+                        continue;
+                    };
+                    let ExprKind::Name { id, .. } = &value.node else {
+                        continue;
+                    };
+                    // Need to consider the two cases:
+                    //  Case 1) Call to class function i.e. id = `self`
+                    //  Case 2) Call to class ancestor function i.e. id = ancestor_name
+                    // We leave checking whether function in case 2 belonged to class ancestor or not to type checker
+                    //
+                    // According to current handling of `self`, function definition are fixed and do not change regardless
+                    // of which object is passed as `self` i.e. virtual polymorphism is not supported
+                    // Therefore, we change class id for case 2 to reflect behavior of our compiler
+
+                    let class_name = if *id == "self".into() {
+                        let ast::StmtKind::ClassDef { name, .. } =
+                            &definition_ast_list[class_id].1.as_ref().unwrap().node
+                        else {
+                            unreachable!()
+                        };
+                        name
+                    } else {
+                        id
+                    };
+
+                    let parent_method = definition_ast_list.iter().find_map(|def| {
+                        let (
+                            class_def,
+                            Some(ast::Located {
+                                node: ast::StmtKind::ClassDef { name, body, .. },
+                                ..
+                            }),
+                        ) = &def
+                        else {
+                            return None;
+                        };
+                        let TopLevelDef::Class { object_id: class_id, .. } = &*class_def.read()
+                        else {
+                            unreachable!()
+                        };
+
+                        if name == class_name {
+                            body.iter().find_map(|m| {
+                                let ast::StmtKind::FunctionDef { name, body, .. } = &m.node else {
+                                    return None;
+                                };
+                                if *name == *attr {
+                                    return Some((body.clone(), class_id.0));
+                                }
+                                None
+                            })
+                        } else {
+                            None
+                        }
+                    });
+
+                    // If method body is none then method does not exist
+                    if let Some((method_body, class_id)) = parent_method {
+                        result.extend(Self::get_all_assigned_field(
+                            class_id,
+                            definition_ast_list,
+                            method_body.as_slice(),
+                        )?);
+                    } else {
+                        return Err(HashSet::from([format!(
+                            "{}.{} not found in class {class_name} at {}",
+                            *id, *attr, value.location
+                        )]));
+                    }
                 }
                 ast::StmtKind::Pass { .. }
                 | ast::StmtKind::Assert { .. }
-                | ast::StmtKind::Expr { .. } => {}
+                | ast::StmtKind::AnnAssign { .. } => {}
 
                 _ => {
                     unimplemented!()
@@ -857,6 +933,139 @@ impl TopLevelComposer {
             ))
         }
     }
+
+    /// Parses the class type variables and direct parents
+    /// we only allow single inheritance
+    pub fn analyze_class_bases(
+        class_def: &Arc<RwLock<TopLevelDef>>,
+        class_ast: &Option<Stmt>,
+        temp_def_list: &[Arc<RwLock<TopLevelDef>>],
+        unifier: &mut Unifier,
+        primitives_store: &PrimitiveStore,
+    ) -> Result<(), HashSet<String>> {
+        let mut class_def = class_def.write();
+        let (class_def_id, class_ancestors, class_bases_ast, class_type_vars, class_resolver) = {
+            let TopLevelDef::Class { object_id, ancestors, type_vars, resolver, .. } =
+                &mut *class_def
+            else {
+                unreachable!()
+            };
+            let Some(ast::Located { node: ast::StmtKind::ClassDef { bases, .. }, .. }) = class_ast
+            else {
+                unreachable!()
+            };
+            (object_id, ancestors, bases, type_vars, resolver.as_ref().unwrap().as_ref())
+        };
+
+        let mut is_generic = false;
+        let mut has_base = false;
+        // Check class bases for typevars
+        for b in class_bases_ast {
+            match &b.node {
+                // analyze typevars bounded to the class,
+                // only support things like `class A(Generic[T, V])`,
+                // things like `class A(Generic[T, V, ImportedModule.T])` is not supported
+                // i.e. only simple names are allowed in the subscript
+                // should update the TopLevelDef::Class.typevars and the TypeEnum::TObj.params
+                ast::ExprKind::Subscript { value, slice, .. } if matches!(&value.node, ast::ExprKind::Name { id, .. } if id == &"Generic".into()) =>
+                {
+                    if is_generic {
+                        return Err(HashSet::from([format!(
+                            "only single Generic[...] is allowed (at {})",
+                            b.location
+                        )]));
+                    }
+                    is_generic = true;
+
+                    let type_var_list: Vec<&ast::Expr<()>>;
+                    // if `class A(Generic[T, V, G])`
+                    if let ast::ExprKind::Tuple { elts, .. } = &slice.node {
+                        type_var_list = elts.iter().collect_vec();
+                    // `class A(Generic[T])`
+                    } else {
+                        type_var_list = vec![&**slice];
+                    }
+
+                    let type_vars = type_var_list
+                        .into_iter()
+                        .map(|e| {
+                            class_resolver.parse_type_annotation(
+                                temp_def_list,
+                                unifier,
+                                primitives_store,
+                                e,
+                            )
+                        })
+                        .collect::<Result<Vec<_>, _>>()?;
+
+                    class_type_vars.extend(type_vars);
+                }
+                ast::ExprKind::Name { .. } | ast::ExprKind::Subscript { .. } => {
+                    if has_base {
+                        return Err(HashSet::from([format!("a class definition can only have at most one base class declaration and one generic declaration (at {})", b.location )]));
+                    }
+                    has_base = true;
+                    // the function parse_ast_to make sure that no type var occurred in
+                    // bast_ty if it is a CustomClassKind
+                    let base_ty = parse_ast_to_type_annotation_kinds(
+                        class_resolver,
+                        temp_def_list,
+                        unifier,
+                        primitives_store,
+                        b,
+                        vec![(*class_def_id, class_type_vars.clone())]
+                            .into_iter()
+                            .collect::<HashMap<_, _>>(),
+                    )?;
+                    if let TypeAnnotation::CustomClass { .. } = &base_ty {
+                        class_ancestors.push(base_ty);
+                    } else {
+                        return Err(HashSet::from([format!(
+                            "class base declaration can only be custom class (at {})",
+                            b.location
+                        )]));
+                    }
+                }
+                _ => {
+                    return Err(HashSet::from([format!(
+                        "unsupported statement in class defintion (at {})",
+                        b.location
+                    )]));
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    /// gets all ancestors of a class
+    pub fn analyze_class_ancestors(
+        class_def: &Arc<RwLock<TopLevelDef>>,
+        temp_def_list: &[Arc<RwLock<TopLevelDef>>],
+    ) {
+        // Check if class has a direct parent
+        let mut class_def = class_def.write();
+        let TopLevelDef::Class { ancestors, type_vars, object_id, .. } = &mut *class_def else {
+            unreachable!()
+        };
+        let mut anc_set = HashMap::new();
+
+        if let Some(ancestor) = ancestors.first() {
+            let TypeAnnotation::CustomClass { id, .. } = ancestor else { unreachable!() };
+            let TopLevelDef::Class { ancestors: parent_ancestors, .. } =
+                &*temp_def_list[id.0].read()
+            else {
+                unreachable!()
+            };
+            for anc in parent_ancestors.iter().skip(1) {
+                let TypeAnnotation::CustomClass { id, .. } = anc else { unreachable!() };
+                anc_set.insert(id, anc.clone());
+            }
+            ancestors.extend(anc_set.into_values());
+        }
+        // push `self` as first ancestor of class
+        ancestors.insert(0, make_self_type_annotation(type_vars.as_slice(), *object_id));
+    }
 }
 
 pub fn parse_parameter_default_value(
@@ -1000,3 +1209,23 @@ pub fn arraylike_get_ndims(unifier: &mut Unifier, ty: Type) -> u64 {
         _ => 0,
     }
 }
+
+/// Extract an ndarray's `ndims` [type][`Type`] in `u64`. Panic if not possible.
+/// The `ndims` must only contain 1 value.
+#[must_use]
+pub fn extract_ndims(unifier: &Unifier, ndims_ty: Type) -> u64 {
+    let ndims_ty_enum = unifier.get_ty_immutable(ndims_ty);
+    let TypeEnum::TLiteral { values, .. } = &*ndims_ty_enum else {
+        panic!("ndims_ty should be a TLiteral");
+    };
+
+    assert_eq!(values.len(), 1, "ndims_ty TLiteral should only contain 1 value");
+
+    let ndims = values[0].clone();
+    u64::try_from(ndims).unwrap()
+}
+
+/// Return an ndarray's `ndims` as a typechecker [`Type`] from its `u64` value.
+pub fn create_ndims(unifier: &mut Unifier, ndims: u64) -> Type {
+    unifier.get_fresh_literal(vec![SymbolValue::U64(ndims)], None)
+}

nac3core/src/toplevel/mod.rs

@@ -6,36 +6,36 @@ use std::{
     sync::Arc,
 };
 
-use super::codegen::CodeGenContext;
-use super::typecheck::type_inferencer::PrimitiveStore;
-use super::typecheck::typedef::{
-    FunSignature, FuncArg, SharedUnifier, Type, TypeEnum, Unifier, VarMap,
-};
-use crate::{
-    codegen::CodeGenerator,
-    symbol_resolver::{SymbolResolver, ValueEnum},
-    typecheck::{
-        type_inferencer::CodeLocation,
-        typedef::{CallId, TypeVarId},
-    },
-};
 use inkwell::values::BasicValueEnum;
 use itertools::Itertools;
-use nac3parser::ast::{self, Location, Stmt, StrRef};
 use parking_lot::RwLock;
 
-#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Hash, Debug)]
+use nac3parser::ast::{self, Expr, Location, Stmt, StrRef};
-pub struct DefinitionId(pub usize);
+
+use crate::{
+    codegen::{CodeGenContext, CodeGenerator},
+    symbol_resolver::{SymbolResolver, ValueEnum},
+    typecheck::{
+        type_inferencer::{CodeLocation, PrimitiveStore},
+        typedef::{
+            CallId, FunSignature, FuncArg, SharedUnifier, Type, TypeEnum, TypeVarId, Unifier,
+            VarMap,
+        },
+    },
+};
+use composer::*;
+use type_annotation::*;
 
 pub mod builtins;
 pub mod composer;
 pub mod helper;
 pub mod numpy;
-pub mod type_annotation;
-use composer::*;
-use type_annotation::*;
 #[cfg(test)]
 mod test;
+pub mod type_annotation;
+
+#[derive(PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Hash, Debug)]
+pub struct DefinitionId(pub usize);
 
 type GenCallCallback = dyn for<'ctx, 'a> Fn(
         &mut CodeGenContext<'ctx, 'a>,
@@ -148,6 +148,25 @@ pub enum TopLevelDef {
         /// Definition location.
         loc: Option<Location>,
     },
+    Variable {
+        /// Qualified name of the global variable, should be unique globally.
+        name: String,
+
+        /// Simple name, the same as in method/function definition.
+        simple_name: StrRef,
+
+        /// Type of the global variable.
+        ty: Type,
+
+        /// The declared type of the global variable, or [`None`] if no type annotation is provided.
+        ty_decl: Option<Expr>,
+
+        /// Symbol resolver of the module defined the class.
+        resolver: Option<Arc<dyn SymbolResolver + Send + Sync>>,
+
+        /// Definition location.
+        loc: Option<Location>,
+    },
 }
 
 pub struct TopLevelContext {

nac3core/src/toplevel/numpy.rs

@@ -1,12 +1,11 @@
-use crate::{
-    toplevel::helper::PrimDef,
-    typecheck::{
-        type_inferencer::PrimitiveStore,
-        typedef::{Type, TypeEnum, TypeVarId, Unifier, VarMap},
-    },
-};
 use itertools::Itertools;
 
+use super::helper::PrimDef;
+use crate::typecheck::{
+    type_inferencer::PrimitiveStore,
+    typedef::{Type, TypeEnum, TypeVarId, Unifier, VarMap},
+};
+
 /// Creates a `ndarray` [`Type`] with the given type arguments.
 ///
 /// * `dtype` - The element type of the `ndarray`, or [`None`] if the type variable is not

nac3core/src/toplevel/snapshots/nac3core__toplevel__test__test_analyze__generic_class.snap

@@ -3,10 +3,10 @@ source: nac3core/src/toplevel/test.rs
 expression: res_vec
 ---
 [
-    "Class {\nname: \"Generic_A\",\nancestors: [\"Generic_A[V]\", \"B\"],\nfields: [\"aa\", \"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"foo\", \"fn[[b:T], none]\"), (\"fun\", \"fn[[a:int32], V]\")],\ntype_vars: [\"V\"]\n}\n",
-    "Function {\nname: \"Generic_A.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
-    "Function {\nname: \"Generic_A.fun\",\nsig: \"fn[[a:int32], V]\",\nvar_id: [TypeVarId(241)]\n}\n",
     "Class {\nname: \"B\",\nancestors: [\"B\"],\nfields: [\"aa\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"foo\", \"fn[[b:T], none]\")],\ntype_vars: []\n}\n",
     "Function {\nname: \"B.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
     "Function {\nname: \"B.foo\",\nsig: \"fn[[b:T], none]\",\nvar_id: []\n}\n",
+    "Class {\nname: \"Generic_A\",\nancestors: [\"Generic_A[V]\", \"B\"],\nfields: [\"aa\", \"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"foo\", \"fn[[b:T], none]\"), (\"fun\", \"fn[[a:int32], V]\")],\ntype_vars: [\"V\"]\n}\n",
+    "Function {\nname: \"Generic_A.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
+    "Function {\nname: \"Generic_A.fun\",\nsig: \"fn[[a:int32], V]\",\nvar_id: [TypeVarId(246)]\n}\n",
 ]

nac3core/src/toplevel/snapshots/nac3core__toplevel__test__test_analyze__simple_class_compose.snap

@@ -7,11 +7,11 @@ expression: res_vec
     "Function {\nname: \"A.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
     "Function {\nname: \"A.fun\",\nsig: \"fn[[b:B], none]\",\nvar_id: []\n}\n",
     "Function {\nname: \"A.foo\",\nsig: \"fn[[a:T, b:V], none]\",\nvar_id: [TypeVarId(249)]\n}\n",
-    "Class {\nname: \"B\",\nancestors: [\"B\", \"C\", \"A\"],\nfields: [\"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[b:B], none]\"), (\"foo\", \"fn[[a:T, b:V], none]\")],\ntype_vars: []\n}\n",
-    "Function {\nname: \"B.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
     "Class {\nname: \"C\",\nancestors: [\"C\", \"A\"],\nfields: [\"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[b:B], none]\"), (\"foo\", \"fn[[a:T, b:V], none]\")],\ntype_vars: []\n}\n",
     "Function {\nname: \"C.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
     "Function {\nname: \"C.fun\",\nsig: \"fn[[b:B], none]\",\nvar_id: []\n}\n",
+    "Class {\nname: \"B\",\nancestors: [\"B\", \"C\", \"A\"],\nfields: [\"a\"],\nmethods: [(\"__init__\", \"fn[[], none]\"), (\"fun\", \"fn[[b:B], none]\"), (\"foo\", \"fn[[a:T, b:V], none]\")],\ntype_vars: []\n}\n",
+    "Function {\nname: \"B.__init__\",\nsig: \"fn[[], none]\",\nvar_id: []\n}\n",
     "Function {\nname: \"foo\",\nsig: \"fn[[a:A], none]\",\nvar_id: []\n}\n",
     "Function {\nname: \"ff\",\nsig: \"fn[[a:T], V]\",\nvar_id: [TypeVarId(257)]\n}\n",
 ]

nac3core/src/toplevel/test.rs

@@ -1,21 +1,23 @@
-use super::*;
+use std::{collections::HashMap, sync::Arc};
-use crate::toplevel::helper::PrimDef;
+
-use crate::typecheck::typedef::into_var_map;
+use indoc::indoc;
+use parking_lot::Mutex;
+use test_case::test_case;
+
+use nac3parser::{
+    ast::{fold::Fold, FileName},
+    parser::parse_program,
+};
+
+use super::{helper::PrimDef, DefinitionId, *};
 use crate::{
     codegen::CodeGenContext,
     symbol_resolver::{SymbolResolver, ValueEnum},
-    toplevel::DefinitionId,
     typecheck::{
         type_inferencer::PrimitiveStore,
-        typedef::{Type, Unifier},
+        typedef::{into_var_map, Type, Unifier},
     },
 };
-use indoc::indoc;
-use nac3parser::ast::FileName;
-use nac3parser::{ast::fold::Fold, parser::parse_program};
-use parking_lot::Mutex;
-use std::{collections::HashMap, sync::Arc};
-use test_case::test_case;
 
 struct ResolverInternal {
     id_to_type: Mutex<HashMap<StrRef, Type>>,
@@ -62,6 +64,7 @@ impl SymbolResolver for Resolver {
         &self,
         _: StrRef,
         _: &mut CodeGenContext<'ctx, '_>,
+        _: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>> {
         unimplemented!()
     }
@@ -226,11 +229,6 @@ fn test_simple_function_analyze(source: &[&str], tys: &[&str], names: &[&str]) {
                 def foo(self, a: T, b: V):
                     pass
         "},
-        indoc! {"
-            class B(C):
-                def __init__(self):
-                    pass
-        "},
         indoc! {"
             class C(A):
                 def __init__(self):
@@ -239,6 +237,11 @@ fn test_simple_function_analyze(source: &[&str], tys: &[&str], names: &[&str]) {
                     a = 1
                     pass
         "},
+        indoc! {"
+            class B(C):
+                def __init__(self):
+                    pass
+        "},
         indoc! {"
             def foo(a: A):
                 pass
@@ -253,6 +256,14 @@ fn test_simple_function_analyze(source: &[&str], tys: &[&str], names: &[&str]) {
 )]
 #[test_case(
     &[
+        indoc! {"
+        class B:
+            aa: bool
+            def __init__(self):
+                self.aa = False
+            def foo(self, b: T):
+                pass
+        "},
         indoc! {"
             class Generic_A(Generic[V], B):
                 a: int64
@@ -260,14 +271,6 @@ fn test_simple_function_analyze(source: &[&str], tys: &[&str], names: &[&str]) {
                     self.a = 123123123123
                 def fun(self, a: int32) -> V:
                     pass
-        "},
-        indoc! {"
-            class B:
-                aa: bool
-                def __init__(self):
-                    self.aa = False
-                def foo(self, b: T):
-                    pass
         "}
     ],
     &[];
@@ -387,18 +390,18 @@ fn test_simple_function_analyze(source: &[&str], tys: &[&str], names: &[&str]) {
                     pass
         "}
     ],
-    &["cyclic inheritance detected"];
+    &["NameError: name 'B' is not defined (at unknown:1:9)"];
     "cyclic1"
 )]
 #[test_case(
     &[
         indoc! {"
-            class A(B[bool, int64]):
+        class B(Generic[V, T], C[int32]):
-                def __init__(self):
+            def __init__(self):
-                    pass
+                pass
         "},
         indoc! {"
-            class B(Generic[V, T], C[int32]):
+            class A(B[bool, int64]):
                 def __init__(self):
                     pass
         "},
@@ -408,7 +411,7 @@ fn test_simple_function_analyze(source: &[&str], tys: &[&str], names: &[&str]) {
                     pass
         "},
     ],
-    &["cyclic inheritance detected"];
+    &["NameError: name 'C' is not defined (at unknown:1:25)"];
     "cyclic2"
 )]
 #[test_case(
@@ -432,11 +435,6 @@ fn test_simple_function_analyze(source: &[&str], tys: &[&str], names: &[&str]) {
 )]
 #[test_case(
     &[
-        indoc! {"
-            class A(B, Generic[T], C):
-                def __init__(self):
-                    pass
-        "},
         indoc! {"
             class B:
                 def __init__(self):
@@ -446,6 +444,11 @@ fn test_simple_function_analyze(source: &[&str], tys: &[&str], names: &[&str]) {
             class C:
                 def __init__(self):
                     pass
+        "},
+        indoc! {"
+        class A(B, Generic[T], C):
+            def __init__(self):
+                pass
         "}
 
     ],

nac3core/src/toplevel/type_annotation.rs

@@ -1,10 +1,13 @@
-use super::*;
-use crate::symbol_resolver::SymbolValue;
-use crate::toplevel::helper::{PrimDef, PrimDefDetails};
-use crate::typecheck::typedef::VarMap;
-use nac3parser::ast::Constant;
 use strum::IntoEnumIterator;
 
+use nac3parser::ast::Constant;
+
+use super::{
+    helper::{PrimDef, PrimDefDetails},
+    *,
+};
+use crate::{symbol_resolver::SymbolValue, typecheck::typedef::VarMap};
+
 #[derive(Clone, Debug)]
 pub enum TypeAnnotation {
     Primitive(Type),
@@ -97,7 +100,13 @@ pub fn parse_ast_to_type_annotation_kinds<T, S: std::hash::BuildHasher + Clone>(
             Ok(TypeAnnotation::CustomClass { id: PrimDef::Exception.id(), params: Vec::default() })
         } else if let Ok(obj_id) = resolver.get_identifier_def(*id) {
             let type_vars = {
-                let def_read = top_level_defs[obj_id.0].try_read();
+                let Some(top_level_def) = top_level_defs.get(obj_id.0) else {
+                    return Err(HashSet::from([format!(
+                        "NameError: name '{id}' is not defined (at {})",
+                        expr.location
+                    )]));
+                };
+                let def_read = top_level_def.try_read();
                 if let Some(def_read) = def_read {
                     if let TopLevelDef::Class { type_vars, .. } = &*def_read {
                         type_vars.clone()
@@ -152,12 +161,17 @@ pub fn parse_ast_to_type_annotation_kinds<T, S: std::hash::BuildHasher + Clone>(
             }
             let obj_id = resolver.get_identifier_def(*id)?;
             let type_vars = {
-                let def_read = top_level_defs[obj_id.0].try_read();
+                let Some(top_level_def) = top_level_defs.get(obj_id.0) else {
+                    return Err(HashSet::from([format!(
+                        "NameError: name '{id}' is not defined (at {})",
+                        expr.location
+                    )]));
+                };
+                let def_read = top_level_def.try_read();
                 if let Some(def_read) = def_read {
                     let TopLevelDef::Class { type_vars, .. } = &*def_read else {
                         unreachable!("must be class here")
                     };
-
                     type_vars.clone()
                 } else {
                     locked.get(&obj_id).unwrap().clone()

nac3core/src/typecheck/function_check.rs

@@ -1,13 +1,19 @@
-use crate::toplevel::helper::PrimDef;
+use std::{
+    collections::{HashMap, HashSet},
+    iter::once,
+};
 
-use super::type_inferencer::Inferencer;
-use super::typedef::{Type, TypeEnum};
 use nac3parser::ast::{
     self, Constant, Expr, ExprKind,
     Operator::{LShift, RShift},
     Stmt, StmtKind, StrRef,
 };
-use std::{collections::HashSet, iter::once};
+
+use super::{
+    type_inferencer::{DeclarationSource, IdentifierInfo, Inferencer},
+    typedef::{Type, TypeEnum},
+};
+use crate::toplevel::helper::PrimDef;
 
 impl<'a> Inferencer<'a> {
     fn should_have_value(&mut self, expr: &Expr<Option<Type>>) -> Result<(), HashSet<String>> {
@@ -21,15 +27,29 @@ impl<'a> Inferencer<'a> {
     fn check_pattern(
         &mut self,
         pattern: &Expr<Option<Type>>,
-        defined_identifiers: &mut HashSet<StrRef>,
+        defined_identifiers: &mut HashMap<StrRef, IdentifierInfo>,
     ) -> Result<(), HashSet<String>> {
         match &pattern.node {
             ExprKind::Name { id, .. } if id == &"none".into() => {
                 Err(HashSet::from([format!("cannot assign to a `none` (at {})", pattern.location)]))
             }
             ExprKind::Name { id, .. } => {
-                if !defined_identifiers.contains(id) {
+                // If `id` refers to a declared symbol, reject this assignment if it is used in the
-                    defined_identifiers.insert(*id);
+                // context of an (implicit) global variable
+                if let Some(id_info) = defined_identifiers.get(id) {
+                    if matches!(
+                        id_info.source,
+                        DeclarationSource::Global { is_explicit: Some(false) }
+                    ) {
+                        return Err(HashSet::from([format!(
+                            "cannot access local variable '{id}' before it is declared (at {})",
+                            pattern.location
+                        )]));
+                    }
+                }
+
+                if !defined_identifiers.contains_key(id) {
+                    defined_identifiers.insert(*id, IdentifierInfo::default());
                 }
                 self.should_have_value(pattern)?;
                 Ok(())
@@ -69,7 +89,7 @@ impl<'a> Inferencer<'a> {
     fn check_expr(
         &mut self,
         expr: &Expr<Option<Type>>,
-        defined_identifiers: &mut HashSet<StrRef>,
+        defined_identifiers: &mut HashMap<StrRef, IdentifierInfo>,
     ) -> Result<(), HashSet<String>> {
         // there are some cases where the custom field is None
         if let Some(ty) = &expr.custom {
@@ -90,7 +110,7 @@ impl<'a> Inferencer<'a> {
                     return Ok(());
                 }
                 self.should_have_value(expr)?;
-                if !defined_identifiers.contains(id) {
+                if !defined_identifiers.contains_key(id) {
                     match self.function_data.resolver.get_symbol_type(
                         self.unifier,
                         &self.top_level.definitions.read(),
@@ -98,7 +118,22 @@ impl<'a> Inferencer<'a> {
                         *id,
                     ) {
                         Ok(_) => {
-                            self.defined_identifiers.insert(*id);
+                            let is_global = self.is_id_global(*id);
+
+                            defined_identifiers.insert(
+                                *id,
+                                IdentifierInfo {
+                                    source: match is_global {
+                                        Some(true) => {
+                                            DeclarationSource::Global { is_explicit: Some(false) }
+                                        }
+                                        Some(false) => {
+                                            DeclarationSource::Global { is_explicit: None }
+                                        }
+                                        None => DeclarationSource::Local,
+                                    },
+                                },
+                            );
                         }
                         Err(e) => {
                             return Err(HashSet::from([format!(
@@ -171,9 +206,7 @@ impl<'a> Inferencer<'a> {
                 let mut defined_identifiers = defined_identifiers.clone();
                 for arg in &args.args {
                     // TODO: should we check the types here?
-                    if !defined_identifiers.contains(&arg.node.arg) {
+                    defined_identifiers.entry(arg.node.arg).or_default();
-                        defined_identifiers.insert(arg.node.arg);
-                    }
                 }
                 self.check_expr(body, &mut defined_identifiers)?;
             }
@@ -236,7 +269,7 @@ impl<'a> Inferencer<'a> {
     fn check_stmt(
         &mut self,
         stmt: &Stmt<Option<Type>>,
-        defined_identifiers: &mut HashSet<StrRef>,
+        defined_identifiers: &mut HashMap<StrRef, IdentifierInfo>,
     ) -> Result<bool, HashSet<String>> {
         match &stmt.node {
             StmtKind::For { target, iter, body, orelse, .. } => {
@@ -262,9 +295,11 @@ impl<'a> Inferencer<'a> {
                 let body_returned = self.check_block(body, &mut body_identifiers)?;
                 let orelse_returned = self.check_block(orelse, &mut orelse_identifiers)?;
 
-                for ident in &body_identifiers {
+                for ident in body_identifiers.keys() {
-                    if !defined_identifiers.contains(ident) && orelse_identifiers.contains(ident) {
+                    if !defined_identifiers.contains_key(ident)
-                        defined_identifiers.insert(*ident);
+                        && orelse_identifiers.contains_key(ident)
+                    {
+                        defined_identifiers.insert(*ident, IdentifierInfo::default());
                     }
                 }
                 Ok(body_returned && orelse_returned)
@@ -295,7 +330,7 @@ impl<'a> Inferencer<'a> {
                     let mut defined_identifiers = defined_identifiers.clone();
                     let ast::ExcepthandlerKind::ExceptHandler { name, body, .. } = &handler.node;
                     if let Some(name) = name {
-                        defined_identifiers.insert(*name);
+                        defined_identifiers.insert(*name, IdentifierInfo::default());
                     }
                     self.check_block(body, &mut defined_identifiers)?;
                 }
@@ -359,6 +394,44 @@ impl<'a> Inferencer<'a> {
                 }
                 Ok(true)
             }
+            StmtKind::Global { names, .. } => {
+                for id in names {
+                    if let Some(id_info) = defined_identifiers.get(id) {
+                        if id_info.source == DeclarationSource::Local {
+                            return Err(HashSet::from([format!(
+                                "name '{id}' is referenced prior to global declaration at {}",
+                                stmt.location,
+                            )]));
+                        }
+
+                        continue;
+                    }
+
+                    match self.function_data.resolver.get_symbol_type(
+                        self.unifier,
+                        &self.top_level.definitions.read(),
+                        self.primitives,
+                        *id,
+                    ) {
+                        Ok(_) => {
+                            defined_identifiers.insert(
+                                *id,
+                                IdentifierInfo {
+                                    source: DeclarationSource::Global { is_explicit: Some(true) },
+                                },
+                            );
+                        }
+                        Err(e) => {
+                            return Err(HashSet::from([format!(
+                                "type error at identifier `{}` ({}) at {}",
+                                id, e, stmt.location
+                            )]))
+                        }
+                    }
+                }
+
+                Ok(false)
+            }
             // break, raise, etc.
             _ => Ok(false),
         }
@@ -367,7 +440,7 @@ impl<'a> Inferencer<'a> {
     pub fn check_block(
         &mut self,
         block: &[Stmt<Option<Type>>],
-        defined_identifiers: &mut HashSet<StrRef>,
+        defined_identifiers: &mut HashMap<StrRef, IdentifierInfo>,
     ) -> Result<bool, HashSet<String>> {
         let mut ret = false;
         for stmt in block {

nac3core/src/typecheck/magic_methods.rs

@@ -1,17 +1,21 @@
-use crate::symbol_resolver::SymbolValue;
+use std::{cmp::max, collections::HashMap, rc::Rc};
-use crate::toplevel::helper::PrimDef;
+
-use crate::toplevel::numpy::{make_ndarray_ty, unpack_ndarray_var_tys};
+use itertools::{iproduct, Itertools};
-use crate::typecheck::{
+use strum::IntoEnumIterator;
+
+use nac3parser::ast::{Cmpop, Operator, StrRef, Unaryop};
+
+use super::{
     type_inferencer::*,
     typedef::{FunSignature, FuncArg, Type, TypeEnum, Unifier, VarMap},
 };
-use itertools::{iproduct, Itertools};
+use crate::{
-use nac3parser::ast::StrRef;
+    symbol_resolver::SymbolValue,
-use nac3parser::ast::{Cmpop, Operator, Unaryop};
+    toplevel::{
-use std::cmp::max;
+        helper::PrimDef,
-use std::collections::HashMap;
+        numpy::{make_ndarray_ty, unpack_ndarray_var_tys},
-use std::rc::Rc;
+    },
-use strum::IntoEnumIterator;
+};
 
 /// The variant of a binary operator.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
@@ -520,6 +524,23 @@ pub fn typeof_binop(
         }
 
         Operator::MatMult => {
+            // NOTE: NumPy matmul's LHS and RHS must both be ndarrays. Scalars are not allowed.
+            match (&*unifier.get_ty(lhs), &*unifier.get_ty(rhs)) {
+                (
+                    TypeEnum::TObj { obj_id: lhs_obj_id, .. },
+                    TypeEnum::TObj { obj_id: rhs_obj_id, .. },
+                ) if *lhs_obj_id == primitives.ndarray.obj_id(unifier).unwrap()
+                    && *rhs_obj_id == primitives.ndarray.obj_id(unifier).unwrap() =>
+                {
+                    // LHS and RHS have valid types
+                }
+                _ => {
+                    let lhs_str = unifier.stringify(lhs);
+                    let rhs_str = unifier.stringify(rhs);
+                    return Err(format!("ndarray.__matmul__ only accepts ndarray operands, but left operand has type {lhs_str}, and right operand has type {rhs_str}"));
+                }
+            }
+
             let (_, lhs_ndims) = unpack_ndarray_var_tys(unifier, lhs);
             let lhs_ndims = match &*unifier.get_ty_immutable(lhs_ndims) {
                 TypeEnum::TLiteral { values, .. } => {

nac3core/src/typecheck/type_error.rs

@@ -1,14 +1,13 @@
-use std::collections::HashMap;
+use std::{collections::HashMap, fmt::Display};
-use std::fmt::Display;
 
-use crate::typecheck::{magic_methods::HasOpInfo, typedef::TypeEnum};
+use itertools::Itertools;
+
+use nac3parser::ast::{Cmpop, Location, StrRef};
 
 use super::{
-    magic_methods::Binop,
+    magic_methods::{Binop, HasOpInfo},
-    typedef::{RecordKey, Type, Unifier},
+    typedef::{RecordKey, Type, TypeEnum, Unifier},
 };
-use itertools::Itertools;
-use nac3parser::ast::{Cmpop, Location, StrRef};
 
 #[derive(Debug, Clone)]
 pub enum TypeErrorKind {

nac3core/src/typecheck/type_inferencer/mod.rs

@@ -1,14 +1,25 @@
-use std::cmp::max;
+use std::{
-use std::collections::{HashMap, HashSet};
+    cell::RefCell,
-use std::convert::{From, TryInto};
+    cmp::max,
-use std::iter::once;
+    collections::{HashMap, HashSet},
-use std::{cell::RefCell, sync::Arc};
+    convert::{From, TryInto},
+    iter::once,
+    sync::Arc,
+};
+
+use itertools::{izip, Itertools};
+
+use nac3parser::ast::{
+    self,
+    fold::{self, Fold},
+    Arguments, Comprehension, ExprContext, ExprKind, Ident, Located, Location, StrRef,
+};
 
 use super::{
     magic_methods::*,
     type_error::{TypeError, TypeErrorKind},
     typedef::{
-        into_var_map, iter_type_vars, Call, CallId, FunSignature, FuncArg, OperatorInfo,
+        into_var_map, iter_type_vars, Call, CallId, FunSignature, FuncArg, Mapping, OperatorInfo,
         RecordField, RecordKey, Type, TypeEnum, TypeVar, Unifier, VarMap,
     },
 };
@@ -17,15 +28,9 @@ use crate::{
     toplevel::{
         helper::{arraylike_flatten_element_type, arraylike_get_ndims, PrimDef},
         numpy::{make_ndarray_ty, unpack_ndarray_var_tys},
+        type_annotation::TypeAnnotation,
         TopLevelContext, TopLevelDef,
     },
-    typecheck::typedef::Mapping,
-};
-use itertools::{izip, Itertools};
-use nac3parser::ast::{
-    self,
-    fold::{self, Fold},
-    Arguments, Comprehension, ExprContext, ExprKind, Located, Location, StrRef,
 };
 
 #[cfg(test)]
@@ -83,6 +88,40 @@ impl PrimitiveStore {
     }
 }
 
+/// The location where an identifier declaration refers to.
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum DeclarationSource {
+    /// Local scope.
+    Local,
+
+    /// Global scope.
+    Global {
+        /// Whether the identifier is declared by the use of `global` statement. This field is
+        /// [`None`] if the identifier does not refer to a variable.
+        is_explicit: Option<bool>,
+    },
+}
+
+/// Information regarding a defined identifier.
+#[derive(Clone, Copy, Debug)]
+pub struct IdentifierInfo {
+    /// Whether this identifier refers to a global variable.
+    pub source: DeclarationSource,
+}
+
+impl Default for IdentifierInfo {
+    fn default() -> Self {
+        IdentifierInfo { source: DeclarationSource::Local }
+    }
+}
+
+impl IdentifierInfo {
+    #[must_use]
+    pub fn new() -> IdentifierInfo {
+        IdentifierInfo::default()
+    }
+}
+
 pub struct FunctionData {
     pub resolver: Arc<dyn SymbolResolver + Send + Sync>,
     pub return_type: Option<Type>,
@@ -91,7 +130,7 @@ pub struct FunctionData {
 
 pub struct Inferencer<'a> {
     pub top_level: &'a TopLevelContext,
-    pub defined_identifiers: HashSet<StrRef>,
+    pub defined_identifiers: HashMap<StrRef, IdentifierInfo>,
     pub function_data: &'a mut FunctionData,
     pub unifier: &'a mut Unifier,
     pub primitives: &'a PrimitiveStore,
@@ -102,6 +141,7 @@ pub struct Inferencer<'a> {
 }
 
 type InferenceError = HashSet<String>;
+type OverrideResult = Result<Option<ast::Expr<Option<Type>>>, InferenceError>;
 
 struct NaiveFolder();
 impl Fold<()> for NaiveFolder {
@@ -222,9 +262,7 @@ impl<'a> Fold<()> for Inferencer<'a> {
                                 handler.location,
                             ));
                             if let Some(name) = name {
-                                if !self.defined_identifiers.contains(&name) {
+                                self.defined_identifiers.entry(name).or_default();
-                                    self.defined_identifiers.insert(name);
-                                }
                                 if let Some(old_typ) = self.variable_mapping.insert(name, typ) {
                                     let loc = handler.location;
                                     self.unifier.unify(old_typ, typ).map_err(|e| {
@@ -376,6 +414,7 @@ impl<'a> Fold<()> for Inferencer<'a> {
             | ast::StmtKind::Continue { .. }
             | ast::StmtKind::Expr { .. }
             | ast::StmtKind::For { .. }
+            | ast::StmtKind::Global { .. }
             | ast::StmtKind::Pass { .. }
             | ast::StmtKind::Try { .. } => {}
             ast::StmtKind::If { test, .. } | ast::StmtKind::While { test, .. } => {
@@ -497,9 +536,8 @@ impl<'a> Fold<()> for Inferencer<'a> {
             }
             ast::StmtKind::Assert { test, msg, .. } => {
                 self.unify(test.custom.unwrap(), self.primitives.bool, &test.location)?;
-                match msg {
+                if let Some(m) = msg {
-                    Some(m) => self.unify(m.custom.unwrap(), self.primitives.str, &m.location)?,
+                    self.unify(m.custom.unwrap(), self.primitives.str, &m.location)?;
-                    None => (),
                 }
             }
             _ => return report_error("Unsupported statement type", stmt.location),
@@ -547,7 +585,7 @@ impl<'a> Fold<()> for Inferencer<'a> {
                         unreachable!("must be tobj")
                     }
                 } else {
-                    if !self.defined_identifiers.contains(id) {
+                    if !self.defined_identifiers.contains_key(id) {
                         match self.function_data.resolver.get_symbol_type(
                             self.unifier,
                             &self.top_level.definitions.read(),
@@ -555,7 +593,22 @@ impl<'a> Fold<()> for Inferencer<'a> {
                             *id,
                         ) {
                             Ok(_) => {
-                                self.defined_identifiers.insert(*id);
+                                let is_global = self.is_id_global(*id);
+
+                                self.defined_identifiers.insert(
+                                    *id,
+                                    IdentifierInfo {
+                                        source: match is_global {
+                                            Some(true) => DeclarationSource::Global {
+                                                is_explicit: Some(false),
+                                            },
+                                            Some(false) => {
+                                                DeclarationSource::Global { is_explicit: None }
+                                            }
+                                            None => DeclarationSource::Local,
+                                        },
+                                    },
+                                );
                             }
                             Err(e) => {
                                 return report_error(
@@ -620,8 +673,8 @@ impl<'a> Inferencer<'a> {
     fn infer_pattern<T>(&mut self, pattern: &ast::Expr<T>) -> Result<(), InferenceError> {
         match &pattern.node {
             ExprKind::Name { id, .. } => {
-                if !self.defined_identifiers.contains(id) {
+                if !self.defined_identifiers.contains_key(id) {
-                    self.defined_identifiers.insert(*id);
+                    self.defined_identifiers.insert(*id, IdentifierInfo::default());
                 }
                 Ok(())
             }
@@ -730,8 +783,8 @@ impl<'a> Inferencer<'a> {
         let mut defined_identifiers = self.defined_identifiers.clone();
         for arg in &args.args {
             let name = &arg.node.arg;
-            if !defined_identifiers.contains(name) {
+            if !defined_identifiers.contains_key(name) {
-                defined_identifiers.insert(*name);
+                defined_identifiers.insert(*name, IdentifierInfo::default());
             }
         }
         let fn_args: Vec<_> = args
@@ -1548,36 +1601,29 @@ impl<'a> Inferencer<'a> {
         }
         // 2-argument ndarray n-dimensional creation functions
         if id == &"np_full".into() && args.len() == 2 {
-            let ExprKind::List { elts, .. } = &args[0].node else {
+            // Parse arguments
-                return report_error(
+            let shape_expr = args.remove(0);
-                    format!(
+            let (ndims, shape) =
-                        "Expected List literal for first argument of {id}, got {}",
+                self.fold_numpy_function_call_shape_argument(*id, 0, shape_expr)?; // Special handling for `shape`
-                        args[0].node.name()
-                    )
-                    .as_str(),
-                    args[0].location,
-                );
-            };
 
-            let ndims = elts.len() as u64;
+            let fill_value = self.fold_expr(args.remove(0))?;
 
-            let arg0 = self.fold_expr(args.remove(0))?;
+            // Build the return type
-            let arg1 = self.fold_expr(args.remove(0))?;
+            let dtype = fill_value.custom.unwrap();
-
-            let ty = arg1.custom.unwrap();
             let ndims = self.unifier.get_fresh_literal(vec![SymbolValue::U64(ndims)], None);
-            let ret = make_ndarray_ty(self.unifier, self.primitives, Some(ty), Some(ndims));
+            let ret = make_ndarray_ty(self.unifier, self.primitives, Some(dtype), Some(ndims));
+
             let custom = self.unifier.add_ty(TypeEnum::TFunc(FunSignature {
                 args: vec![
                     FuncArg {
                         name: "shape".into(),
-                        ty: arg0.custom.unwrap(),
+                        ty: shape.custom.unwrap(),
                         default_value: None,
                         is_vararg: false,
                     },
                     FuncArg {
                         name: "fill_value".into(),
-                        ty: arg1.custom.unwrap(),
+                        ty: fill_value.custom.unwrap(),
                         default_value: None,
                         is_vararg: false,
                     },
@@ -1595,7 +1641,7 @@ impl<'a> Inferencer<'a> {
                         location: func.location,
                         node: ExprKind::Name { id: *id, ctx: *ctx },
                     }),
-                    args: vec![arg0, arg1],
+                    args: vec![shape, fill_value],
                     keywords: vec![],
                 },
             }));
@@ -1672,6 +1718,86 @@ impl<'a> Inferencer<'a> {
         Ok(None)
     }
 
+    /// Checks whether a class method is calling parent function
+    /// Returns [`None`] if its not a call to parent method, otherwise
+    /// returns a new `func` with class name replaced by `self` and method resolved to its `DefinitionID`
+    ///
+    /// e.g.  A.f1(self, ...) returns Some(self.{DefintionID(f1)})
+    fn check_overriding(&mut self, func: &ast::Expr<()>, args: &[ast::Expr<()>]) -> OverrideResult {
+        // `self` must be first argument for call to parent method
+        if let Some(Located { node: ExprKind::Name { id, .. }, .. }) = &args.first() {
+            if *id != "self".into() {
+                return Ok(None);
+            }
+        } else {
+            return Ok(None);
+        }
+
+        let Located {
+            node: ExprKind::Attribute { value, attr: method_name, ctx }, location, ..
+        } = func
+        else {
+            return Ok(None);
+        };
+        let ExprKind::Name { id: class_name, ctx: class_ctx } = &value.node else {
+            return Ok(None);
+        };
+        let zelf = &self.fold_expr(args[0].clone())?;
+
+        // Check whether the method belongs to class ancestors
+        let def_id = self.unifier.get_ty(zelf.custom.unwrap());
+        let TypeEnum::TObj { obj_id, .. } = def_id.as_ref() else { unreachable!() };
+        let defs = self.top_level.definitions.read();
+        let res = {
+            if let TopLevelDef::Class { ancestors, .. } = &*defs[obj_id.0].read() {
+                let res = ancestors.iter().find_map(|f| {
+                    let TypeAnnotation::CustomClass { id, .. } = f else { unreachable!() };
+                    let TopLevelDef::Class { name, methods, .. } = &*defs[id.0].read() else {
+                        unreachable!()
+                    };
+                    // Class names are stored as `__module__.class`
+                    let name = name.to_string();
+                    let (_, name) = name.rsplit_once('.').unwrap();
+                    if name == class_name.to_string() {
+                        return methods.iter().find_map(|f| {
+                            if f.0 == *method_name {
+                                return Some(*f);
+                            }
+                            None
+                        });
+                    }
+                    None
+                });
+                res
+            } else {
+                None
+            }
+        };
+
+        match res {
+            Some(r) => {
+                let mut new_func = func.clone();
+                let mut new_value = value.clone();
+                new_value.node = ExprKind::Name { id: "self".into(), ctx: *class_ctx };
+                new_func.node =
+                    ExprKind::Attribute { value: new_value.clone(), attr: *method_name, ctx: *ctx };
+
+                let mut new_func = self.fold_expr(new_func)?;
+
+                let ExprKind::Attribute { value, .. } = new_func.node else { unreachable!() };
+                new_func.node =
+                    ExprKind::Attribute { value, attr: r.2 .0.to_string().into(), ctx: *ctx };
+                new_func.custom = Some(r.1);
+
+                Ok(Some(new_func))
+            }
+            None => report_error(
+                format!("Ancestor method [{class_name}.{method_name}] should be defined with same decorator as its overridden version").as_str(),
+                *location,
+            ),
+        }
+    }
+
     fn fold_call(
         &mut self,
         location: Location,
@@ -1685,8 +1811,20 @@ impl<'a> Inferencer<'a> {
             return Ok(spec_call_func);
         }
 
-        let func = Box::new(self.fold_expr(func)?);
+        // Check for call to parent method
-        let args = args.into_iter().map(|v| self.fold_expr(v)).collect::<Result<Vec<_>, _>>()?;
+        let override_res = self.check_overriding(&func, &args)?;
+        let is_override = override_res.is_some();
+        let func = if is_override { override_res.unwrap() } else { self.fold_expr(func)? };
+        let func = Box::new(func);
+
+        let mut args =
+            args.into_iter().map(|v| self.fold_expr(v)).collect::<Result<Vec<_>, _>>()?;
+
+        // TODO: Handle passing of self to functions to allow runtime lookup of functions to be called
+        // Currently removing `self` and using compile time function definitions
+        if is_override {
+            args.remove(0);
+        }
         let keywords = keywords
             .into_iter()
             .map(|v| fold::fold_keyword(self, v))
@@ -2546,4 +2684,22 @@ impl<'a> Inferencer<'a> {
         self.constrain(body.custom.unwrap(), orelse.custom.unwrap(), &body.location)?;
         Ok(body.custom.unwrap())
     }
+
+    /// Determines whether the given `id` refers to a global symbol.
+    ///
+    /// Returns `Some(true)` if `id` refers to a global variable, `Some(false)` if `id` refers to a
+    /// class/function, and `None` if `id` refers to a local symbol.
+    pub(super) fn is_id_global(&self, id: Ident) -> Option<bool> {
+        self.top_level
+            .definitions
+            .read()
+            .iter()
+            .map(|def| match *def.read() {
+                TopLevelDef::Class { name, .. } => (name, false),
+                TopLevelDef::Function { simple_name, .. } => (simple_name, false),
+                TopLevelDef::Variable { simple_name, .. } => (simple_name, true),
+            })
+            .find(|(global, _)| global == &id)
+            .map(|(_, has_explicit_prop)| has_explicit_prop)
+    }
 }

nac3core/src/typecheck/type_inferencer/test.rs

@@ -1,18 +1,20 @@
-use super::super::{magic_methods::with_fields, typedef::*};
+use std::iter::zip;
-use super::*;
+
-use crate::{
-    codegen::CodeGenContext,
-    symbol_resolver::ValueEnum,
-    toplevel::{helper::PrimDef, DefinitionId, TopLevelDef},
-};
 use indexmap::IndexMap;
 use indoc::indoc;
-use nac3parser::ast::FileName;
-use nac3parser::parser::parse_program;
 use parking_lot::RwLock;
-use std::iter::zip;
 use test_case::test_case;
 
+use nac3parser::{ast::FileName, parser::parse_program};
+
+use super::*;
+use crate::{
+    codegen::{CodeGenContext, CodeGenerator},
+    symbol_resolver::ValueEnum,
+    toplevel::{helper::PrimDef, DefinitionId, TopLevelDef},
+    typecheck::{magic_methods::with_fields, typedef::*},
+};
+
 struct Resolver {
     id_to_type: HashMap<StrRef, Type>,
     id_to_def: HashMap<StrRef, DefinitionId>,
@@ -41,6 +43,7 @@ impl SymbolResolver for Resolver {
         &self,
         _: StrRef,
         _: &mut CodeGenContext<'ctx, '_>,
+        _: &mut dyn CodeGenerator,
     ) -> Option<ValueEnum<'ctx>> {
         unimplemented!()
     }
@@ -517,7 +520,7 @@ impl TestEnvironment {
             primitives: &mut self.primitives,
             virtual_checks: &mut self.virtual_checks,
             calls: &mut self.calls,
-            defined_identifiers: HashSet::default(),
+            defined_identifiers: HashMap::default(),
             in_handler: false,
         }
     }
@@ -593,8 +596,9 @@ fn test_basic(source: &str, mapping: &HashMap<&str, &str>, virtuals: &[(&str, &s
     println!("source:\n{source}");
     let mut env = TestEnvironment::new();
     let id_to_name = std::mem::take(&mut env.id_to_name);
-    let mut defined_identifiers: HashSet<_> = env.identifier_mapping.keys().copied().collect();
+    let mut defined_identifiers: HashMap<_, _> =
-    defined_identifiers.insert("virtual".into());
+        env.identifier_mapping.keys().copied().map(|id| (id, IdentifierInfo::default())).collect();
+    defined_identifiers.insert("virtual".into(), IdentifierInfo::default());
     let mut inferencer = env.get_inferencer();
     inferencer.defined_identifiers.clone_from(&defined_identifiers);
     let statements = parse_program(source, FileName::default()).unwrap();
@@ -739,8 +743,9 @@ fn test_primitive_magic_methods(source: &str, mapping: &HashMap<&str, &str>) {
     println!("source:\n{source}");
     let mut env = TestEnvironment::basic_test_env();
     let id_to_name = std::mem::take(&mut env.id_to_name);
-    let mut defined_identifiers: HashSet<_> = env.identifier_mapping.keys().copied().collect();
+    let mut defined_identifiers: HashMap<_, _> =
-    defined_identifiers.insert("virtual".into());
+        env.identifier_mapping.keys().copied().map(|id| (id, IdentifierInfo::default())).collect();
+    defined_identifiers.insert("virtual".into(), IdentifierInfo::default());
     let mut inferencer = env.get_inferencer();
     inferencer.defined_identifiers.clone_from(&defined_identifiers);
     let statements = parse_program(source, FileName::default()).unwrap();