StructKind::{traverse -> iter}_fields

This is preferred for user-defined headers.

.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

Cargo.lock

@@ -117,9 +117,9 @@ checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
 
 [[package]]
 name = "cc"
-version = "1.1.13"
+version = "1.1.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "72db2f7947ecee9b03b510377e8bb9077afa27176fdbff55c51027e976fdcc48"
+checksum = "57b6a275aa2903740dc87da01c62040406b8812552e97129a63ea8850a17c6e6"
 dependencies = [
  "shlex",
 ]
@@ -161,7 +161,7 @@ dependencies = [
  "heck 0.5.0",
  "proc-macro2",
  "quote",
- "syn 2.0.75",
+ "syn 2.0.76",
 ]
 
 [[package]]
@@ -310,9 +310,9 @@ dependencies = [
 
 [[package]]
 name = "fastrand"
-version = "2.1.0"
+version = "2.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9fc0510504f03c51ada170672ac806f1f105a88aa97a5281117e1ddc3368e51a"
+checksum = "e8c02a5121d4ea3eb16a80748c74f5549a5665e4c21333c6098f283870fbdea6"
 
 [[package]]
 name = "fixedbitset"
@@ -424,7 +424,7 @@ checksum = "4fa4d8d74483041a882adaa9a29f633253a66dde85055f0495c121620ac484b2"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.75",
+ "syn 2.0.76",
 ]
 
 [[package]]
@@ -510,9 +510,9 @@ checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
 
 [[package]]
 name = "libc"
-version = "0.2.157"
+version = "0.2.158"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "374af5f94e54fa97cf75e945cce8a6b201e88a1a07e688b47dfd2a59c66dbd86"
+checksum = "d8adc4bb1803a324070e64a98ae98f38934d91957a99cfb3a43dcbc01bc56439"
 
 [[package]]
 name = "libloading"
@@ -752,7 +752,7 @@ dependencies = [
  "phf_shared 0.11.2",
  "proc-macro2",
  "quote",
- "syn 2.0.75",
+ "syn 2.0.76",
 ]
 
 [[package]]
@@ -856,7 +856,7 @@ dependencies = [
  "proc-macro2",
  "pyo3-macros-backend",
  "quote",
- "syn 2.0.75",
+ "syn 2.0.76",
 ]
 
 [[package]]
@@ -869,14 +869,14 @@ dependencies = [
  "proc-macro2",
  "pyo3-build-config",
  "quote",
- "syn 2.0.75",
+ "syn 2.0.76",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.36"
+version = "1.0.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0fa76aaf39101c457836aec0ce2316dbdc3ab723cdda1c6bd4e6ad4208acaca7"
+checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
 dependencies = [
  "proc-macro2",
 ]
@@ -942,9 +942,9 @@ dependencies = [
 
 [[package]]
 name = "redox_users"
-version = "0.4.5"
+version = "0.4.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bd283d9651eeda4b2a83a43c1c91b266c40fd76ecd39a50a8c630ae69dc72891"
+checksum = "ba009ff324d1fc1b900bd1fdb31564febe58a8ccc8a6fdbb93b543d33b13ca43"
 dependencies = [
  "getrandom",
  "libredox",
@@ -989,9 +989,9 @@ dependencies = [
 
 [[package]]
 name = "rustix"
-version = "0.38.34"
+version = "0.38.35"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70dc5ec042f7a43c4a73241207cecc9873a06d45debb38b329f8541d85c2730f"
+checksum = "a85d50532239da68e9addb745ba38ff4612a242c1c7ceea689c4bc7c2f43c36f"
 dependencies = [
  "bitflags",
  "errno",
@@ -1035,29 +1035,29 @@ checksum = "61697e0a1c7e512e84a621326239844a24d8207b4669b41bc18b32ea5cbf988b"
 
 [[package]]
 name = "serde"
-version = "1.0.208"
+version = "1.0.209"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cff085d2cb684faa248efb494c39b68e522822ac0de72ccf08109abde717cfb2"
+checksum = "99fce0ffe7310761ca6bf9faf5115afbc19688edd00171d81b1bb1b116c63e09"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.208"
+version = "1.0.209"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "24008e81ff7613ed8e5ba0cfaf24e2c2f1e5b8a0495711e44fcd4882fca62bcf"
+checksum = "a5831b979fd7b5439637af1752d535ff49f4860c0f341d1baeb6faf0f4242170"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.75",
+ "syn 2.0.76",
 ]
 
 [[package]]
 name = "serde_json"
-version = "1.0.125"
+version = "1.0.127"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83c8e735a073ccf5be70aa8066aa984eaf2fa000db6c8d0100ae605b366d31ed"
+checksum = "8043c06d9f82bd7271361ed64f415fe5e12a77fdb52e573e7f06a516dea329ad"
 dependencies = [
  "itoa",
  "memchr",
@@ -1147,7 +1147,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "rustversion",
- "syn 2.0.75",
+ "syn 2.0.76",
 ]
 
 [[package]]
@@ -1163,9 +1163,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.75"
+version = "2.0.76"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f6af063034fc1935ede7be0122941bafa9bacb949334d090b77ca98b5817c7d9"
+checksum = "578e081a14e0cefc3279b0472138c513f37b41a08d5a3cca9b6e4e8ceb6cd525"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1232,7 +1232,7 @@ checksum = "a4558b58466b9ad7ca0f102865eccc95938dca1a74a856f2b57b6629050da261"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.75",
+ "syn 2.0.76",
 ]
 
 [[package]]
@@ -1310,9 +1310,9 @@ checksum = "0336d538f7abc86d282a4189614dfaa90810dfc2c6f6427eaf88e16311dd225d"
 
 [[package]]
 name = "unicode-xid"
-version = "0.2.4"
+version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f962df74c8c05a667b5ee8bcf162993134c104e96440b663c8daa176dc772d8c"
+checksum = "229730647fbc343e3a80e463c1db7f78f3855d3f3739bee0dda773c9a037c90a"
 
 [[package]]
 name = "unicode_names2"
@@ -1510,5 +1510,5 @@ checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.75",
+ "syn 2.0.76",
 ]

nac3artiq/src/codegen.rs

@@ -2,7 +2,7 @@ use nac3core::{
     codegen::{
         classes::{
             ArrayLikeIndexer, ArrayLikeValue, ArraySliceValue, ListValue, NDArrayType,
-            NDArrayValue, RangeValue, UntypedArrayLikeAccessor,
+            NDArrayValue, ProxyType, ProxyValue, RangeValue, UntypedArrayLikeAccessor,
         },
         expr::{destructure_range, gen_call},
         irrt::call_ndarray_calc_size,
@@ -22,7 +22,7 @@ use inkwell::{
     module::Linkage,
     types::{BasicType, IntType},
     values::{BasicValueEnum, PointerValue, StructValue},
-    AddressSpace, IntPredicate,
+    AddressSpace, IntPredicate, OptimizationLevel,
 };
 
 use pyo3::{
@@ -32,6 +32,7 @@ use pyo3::{
 
 use crate::{symbol_resolver::InnerResolver, timeline::TimeFns};
 
+use inkwell::values::IntValue;
 use itertools::Itertools;
 use std::{
     collections::{hash_map::DefaultHasher, HashMap},
@@ -486,13 +487,10 @@ fn format_rpc_arg<'ctx>(
             let buffer = ctx.builder.build_array_alloca(llvm_i8, buffer_size, "rpc.arg").unwrap();
             let buffer = ArraySliceValue::from_ptr_val(buffer, buffer_size, Some("rpc.arg"));
 
-            let ppdata = generator.gen_var_alloc(ctx, llvm_arg_ty.element_type(), None).unwrap();
-            ctx.builder.build_store(ppdata, llvm_arg.data().base_ptr(ctx, generator)).unwrap();
-
             call_memcpy_generic(
                 ctx,
                 buffer.base_ptr(ctx, generator),
-                ppdata,
+                llvm_arg.ptr_to_data(ctx),
                 llvm_pdata_sizeof,
                 llvm_i1.const_zero(),
             );
@@ -528,6 +526,298 @@ 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 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 llvm_i1 = ctx.ctx.bool_type();
+            let llvm_usize = generator.get_size_type(ctx.ctx);
+
+            // 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()
+            };
+
+            // Setup types
+            let (elem_ty, ndims) = unpack_ndarray_var_tys(&mut ctx.unifier, ret_ty);
+            let llvm_elem_ty = ctx.get_llvm_type(generator, elem_ty);
+            let llvm_ret_ty = NDArrayType::new(generator, ctx.ctx, llvm_elem_ty);
+
+            // Allocate the resulting ndarray
+            // A condition after format_rpc_ret ensures this will not be popped this off.
+            let ndarray = llvm_ret_ty.new_value(generator, ctx, Some("rpc.result"));
+
+            // Setup ndims
+            let ndims =
+                if let TypeEnum::TLiteral { values, .. } = &*ctx.unifier.get_ty_immutable(ndims) {
+                    assert_eq!(values.len(), 1);
+
+                    u64::try_from(values[0].clone()).unwrap()
+                } else {
+                    unreachable!();
+                };
+            // Set `ndarray.ndims`
+            ndarray.store_ndims(ctx, generator, llvm_usize.const_int(ndims, false));
+            // Allocate `ndarray.shape` [size_t; ndims]
+            ndarray.create_dim_sizes(ctx, llvm_usize, ndarray.load_ndims(ctx));
+
+            /*
+                ndarray now:
+                  - .ndims: initialized
+                  - .shape: allocated but uninitialized .shape
+                  - .data: uninitialized
+            */
+
+            let llvm_usize_sizeof = ctx
+                .builder
+                .build_int_truncate_or_bit_cast(llvm_usize.size_of(), llvm_usize, "")
+                .unwrap();
+            let llvm_pdata_sizeof = ctx
+                .builder
+                .build_int_truncate_or_bit_cast(
+                    llvm_ret_ty.element_type().size_of().unwrap(),
+                    llvm_usize,
+                    "",
+                )
+                .unwrap();
+            let llvm_elem_sizeof = ctx
+                .builder
+                .build_int_truncate_or_bit_cast(llvm_elem_ty.size_of().unwrap(), llvm_usize, "")
+                .unwrap();
+
+            // Allocates a buffer for the initial RPC'ed object, which is guaranteed to be
+            // (4 + 4 * ndims) bytes with 8-byte alignment
+            let sizeof_dims =
+                ctx.builder.build_int_mul(ndarray.load_ndims(ctx), llvm_usize_sizeof, "").unwrap();
+            let unaligned_buffer_size =
+                ctx.builder.build_int_add(sizeof_dims, llvm_pdata_sizeof, "").unwrap();
+            let buffer_size = round_up(ctx, unaligned_buffer_size, llvm_usize.const_int(8, false));
+
+            let stackptr = call_stacksave(ctx, None);
+            // Just to be absolutely sure, alloca in [i8 x 8] slices to force 8-byte alignment
+            let buffer = ctx
+                .builder
+                .build_array_alloca(
+                    llvm_i8_8,
+                    ctx.builder
+                        .build_int_unsigned_div(buffer_size, llvm_usize.const_int(8, false), "")
+                        .unwrap(),
+                    "rpc.buffer",
+                )
+                .unwrap();
+            let buffer = ctx
+                .builder
+                .build_bitcast(buffer, llvm_pi8, "")
+                .map(BasicValueEnum::into_pointer_value)
+                .unwrap();
+            let buffer = ArraySliceValue::from_ptr_val(buffer, 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]. NOTE: We are allocated [size_t; ndims].
+                    "rpc.size.next",
+                )
+                .map(BasicValueEnum::into_int_value)
+                .unwrap();
+
+            // debug_assert(ndarray_nbytes > 0)
+            if ctx.registry.llvm_options.opt_level == OptimizationLevel::None {
+                ctx.make_assert(
+                    generator,
+                    ctx.builder
+                        .build_int_compare(
+                            IntPredicate::UGT,
+                            ndarray_nbytes,
+                            ndarray_nbytes.get_type().const_zero(),
+                            "",
+                        )
+                        .unwrap(),
+                    "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`.
+            let pbuffer_dims =
+                unsafe { buffer.ptr_offset_unchecked(ctx, generator, &llvm_pdata_sizeof, None) };
+
+            call_memcpy_generic(
+                ctx,
+                ndarray.dim_sizes().base_ptr(ctx, generator),
+                pbuffer_dims,
+                sizeof_dims,
+                llvm_i1.const_zero(),
+            );
+            // 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)
+            let num_elements =
+                call_ndarray_calc_size(generator, ctx, &ndarray.dim_sizes(), (None, None));
+
+            // debug_assert(nelems * sizeof(T) >= ndarray_nbytes)
+            if ctx.registry.llvm_options.opt_level == OptimizationLevel::None {
+                let sizeof_data =
+                    ctx.builder.build_int_mul(num_elements, llvm_elem_sizeof, "").unwrap();
+
+                ctx.make_assert(
+                    generator,
+                    ctx.builder.build_int_compare(IntPredicate::UGE,
+                        sizeof_data,
+                        ndarray_nbytes,
+                        "",
+                    ).unwrap(),
+                    "0:AssertionError",
+                    "Unexpected allocation size request for ndarray data - Expected up to {0} bytes, got {1} bytes",
+                    [Some(sizeof_data), Some(ndarray_nbytes), None],
+                    ctx.current_loc,
+                );
+            }
+
+            ndarray.create_data(ctx, llvm_elem_ty, num_elements);
+
+            let ndarray_data = ndarray.data().base_ptr(ctx, generator);
+            let ndarray_data_i8 =
+                ctx.builder.build_pointer_cast(ndarray_data, llvm_pi8, "").unwrap();
+
+            // 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_i8, 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, llvm_elem_sizeof);
+            let alloc_ptr = ctx
+                .builder
+                .build_array_alloca(
+                    llvm_elem_ty,
+                    ctx.builder.build_int_unsigned_div(alloc_size, llvm_elem_sizeof, "").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_bitcast(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_bitcast(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>)>,
@@ -663,63 +953,14 @@ fn rpc_codegen_callback_fn<'ctx>(
     // reclaim stack space used by arguments
     call_stackrestore(ctx, stackptr);
 
-    // -- 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 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)
-    });
+    let result = format_rpc_ret(generator, ctx, fun.0.ret);
 
-    if ctx.unifier.unioned(fun.0.ret, ctx.primitives.none) {
-        ctx.build_call_or_invoke(rpc_recv, &[ptr_type.const_null().into()], "rpc_recv");
-        return Ok(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 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 {
+    if !result.is_some_and(|res| res.get_type().is_pointer_type()) {
+        // An RPC returning an NDArray would not touch here.
         call_stackrestore(ctx, stackptr);
     }
-    Ok(Some(result))
+
+    Ok(result)
 }
 
 pub fn attributes_writeback(

nac3artiq/src/lib.rs

@@ -448,7 +448,6 @@ 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(),
@@ -540,7 +539,6 @@ 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(),
             id_to_pyval: RwLock::default(),
             id_to_primitive: RwLock::default(),
             field_to_val: RwLock::default(),
@@ -557,6 +555,10 @@ impl Nac3 {
             .register_top_level(synthesized.pop().unwrap(), Some(resolver.clone()), "", false)
             .unwrap();
 
+        // Process IRRT
+        let context = inkwell::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();
@@ -727,7 +729,7 @@ impl Nac3 {
             membuffer.lock().push(buffer);
         });
 
-        let context = inkwell::context::Context::create();
+        // Link all modules into `main`.
         let buffers = membuffers.lock();
         let main = context
             .create_module_from_ir(MemoryBuffer::create_from_memory_range(&buffers[0], "main"))
@@ -756,8 +758,7 @@ impl Nac3 {
             )
             .unwrap();
 
-        main.link_in_module(load_irrt(&context))
-            .map_err(|err| CompileError::new_err(err.to_string()))?;
+        main.link_in_module(irrt).map_err(|err| CompileError::new_err(err.to_string()))?;
 
         let mut function_iter = main.get_first_function();
         while let Some(func) = function_iter {

nac3artiq/src/symbol_resolver.rs

@@ -23,7 +23,7 @@ use nac3core::{
     },
 };
 use nac3parser::ast::{self, StrRef};
-use parking_lot::{Mutex, RwLock};
+use parking_lot::RwLock;
 use pyo3::{
     types::{PyDict, PyTuple},
     PyAny, PyObject, PyResult, Python,
@@ -79,7 +79,6 @@ 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,

nac3core/build.rs

@@ -8,37 +8,50 @@ use std::{
 };
 
 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}");
-    let out_dir = env::var("OUT_DIR").unwrap();
-    let out_path = Path::new(&out_dir);
+    match env::var("PROFILE").as_deref() {
+        Ok("debug") => {
+            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()
@@ -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");
-    if env::var("DEBUG_DUMP_IRRT").is_ok() {
-        let mut file = File::create(out_path.join("irrt.ll")).unwrap();
+    // For debugging
+    // Doing `DEBUG_DUMP_IRRT=1 cargo build -p nac3core` dumps the LLVM IR generated
+    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 +1,6 @@
+#include "irrt/exception.hpp"
+#include "irrt/int_types.hpp"
+#include "irrt/list.hpp"
+#include "irrt/math.hpp"
+#include "irrt/ndarray.hpp"
+#include "irrt/slice.hpp"

nac3core/irrt/irrt/cslice.hpp

@@ -0,0 +1,9 @@
+#pragma once
+
+#include "irrt/int_types.hpp"
+
+template<typename SizeT>
+struct CSlice {
+    uint8_t* 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 +1,82 @@
+#pragma once
+
+#include "irrt/cslice.hpp"
+#include "irrt/int_types.hpp"
+
+/**
+ * @brief The int type of ARTIQ exception IDs.
+ */
+typedef int32_t ExceptionId;
+
+/*
+ * 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<const uint8_t*>(filename), .len = __builtin_strlen(filename)},
+        .line = line,
+        .column = 0,
+        .function = {.base = reinterpret_cast<const uint8_t*>(function), .len = __builtin_strlen(function)},
+        .msg = {.base = reinterpret_cast<const uint8_t*>(msg), .len = __builtin_strlen(msg)},
+    };
+    e.params[0] = param0;
+    e.params[1] = param1;
+    e.params[2] = param2;
+    __nac3_raise(reinterpret_cast<void*>(&e));
+    __builtin_unreachable();
+}
+
+/**
+ * @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)
+}  // namespace

nac3core/irrt/irrt/int_types.hpp

@@ -0,0 +1,13 @@
+#pragma once
+
+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;

nac3core/irrt/irrt/list.hpp

@@ -0,0 +1,75 @@
+#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,
+                                             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;
+}
+}  // 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);
+}
+}

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 +1,144 @@
+#pragma once
+
+#include "irrt/int_types.hpp"
+
+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, 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" {
+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);
+}
+}

nac3core/irrt/irrt/slice.hpp

@@ -0,0 +1,28 @@
+#pragma once
+
+#include "irrt/int_types.hpp"
+
+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;
+}
+
+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;
+    }
+}
+}

nac3core/src/codegen/builtin_fns.rs

@@ -9,6 +9,7 @@ use crate::codegen::classes::{
 };
 use crate::codegen::expr::destructure_range;
 use crate::codegen::irrt::calculate_len_for_slice_range;
+use crate::codegen::macros::codegen_unreachable;
 use crate::codegen::numpy::ndarray_elementwise_unaryop_impl;
 use crate::codegen::stmt::gen_for_callback_incrementing;
 use crate::codegen::{extern_fns, irrt, llvm_intrinsics, numpy, CodeGenContext, CodeGenerator};
@@ -20,7 +21,8 @@ use crate::typecheck::typedef::{Type, TypeEnum};
 ///
 /// The generated message will contain the function name and the name of the unsupported type.
 fn unsupported_type(ctx: &CodeGenContext<'_, '_>, fn_name: &str, tys: &[Type]) -> ! {
-    unreachable!(
+    codegen_unreachable!(
+        ctx,
         "{fn_name}() not supported for '{}'",
         tys.iter().map(|ty| format!("'{}'", ctx.unifier.stringify(*ty))).join(", "),
     )
@@ -82,7 +84,7 @@ pub fn call_len<'ctx, G: CodeGenerator + ?Sized>(
 
                 ctx.builder.build_int_truncate_or_bit_cast(len, llvm_i32, "len").unwrap()
             }
-            _ => unreachable!(),
+            _ => codegen_unreachable!(ctx),
         }
     })
 }
@@ -784,7 +786,7 @@ pub fn call_numpy_minimum<'ctx, G: CodeGenerator + ?Sized>(
             } else if is_ndarray2 {
                 unpack_ndarray_var_tys(&mut ctx.unifier, x2_ty).0
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
 
             let x1_scalar_ty = if is_ndarray1 { dtype } else { x1_ty };
@@ -888,7 +890,7 @@ pub fn call_numpy_max_min<'ctx, G: CodeGenerator + ?Sized>(
             match fn_name {
                 "np_argmin" | "np_argmax" => llvm_int64.const_zero().into(),
                 "np_max" | "np_min" => a,
-                _ => unreachable!(),
+                _ => codegen_unreachable!(ctx),
             }
         }
         BasicValueEnum::PointerValue(n)
@@ -943,7 +945,7 @@ pub fn call_numpy_max_min<'ctx, G: CodeGenerator + ?Sized>(
                         "np_argmax" | "np_max" => {
                             call_max(ctx, (elem_ty, accumulator), (elem_ty, elem))
                         }
-                        _ => unreachable!(),
+                        _ => codegen_unreachable!(ctx),
                     };
 
                     let updated_idx = match (accumulator, result) {
@@ -980,7 +982,7 @@ pub fn call_numpy_max_min<'ctx, G: CodeGenerator + ?Sized>(
             match fn_name {
                 "np_argmin" | "np_argmax" => ctx.builder.build_load(res_idx, "").unwrap(),
                 "np_max" | "np_min" => ctx.builder.build_load(accumulator_addr, "").unwrap(),
-                _ => unreachable!(),
+                _ => codegen_unreachable!(ctx),
             }
         }
 
@@ -1046,7 +1048,7 @@ pub fn call_numpy_maximum<'ctx, G: CodeGenerator + ?Sized>(
             } else if is_ndarray2 {
                 unpack_ndarray_var_tys(&mut ctx.unifier, x2_ty).0
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
 
             let x1_scalar_ty = if is_ndarray1 { dtype } else { x1_ty };
@@ -1486,7 +1488,7 @@ pub fn call_numpy_arctan2<'ctx, G: CodeGenerator + ?Sized>(
             } else if is_ndarray2 {
                 unpack_ndarray_var_tys(&mut ctx.unifier, x2_ty).0
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
 
             let x1_scalar_ty = if is_ndarray1 { dtype } else { x1_ty };
@@ -1553,7 +1555,7 @@ pub fn call_numpy_copysign<'ctx, G: CodeGenerator + ?Sized>(
             } else if is_ndarray2 {
                 unpack_ndarray_var_tys(&mut ctx.unifier, x2_ty).0
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
 
             let x1_scalar_ty = if is_ndarray1 { dtype } else { x1_ty };
@@ -1620,7 +1622,7 @@ pub fn call_numpy_fmax<'ctx, G: CodeGenerator + ?Sized>(
             } else if is_ndarray2 {
                 unpack_ndarray_var_tys(&mut ctx.unifier, x2_ty).0
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
 
             let x1_scalar_ty = if is_ndarray1 { dtype } else { x1_ty };
@@ -1687,7 +1689,7 @@ pub fn call_numpy_fmin<'ctx, G: CodeGenerator + ?Sized>(
             } else if is_ndarray2 {
                 unpack_ndarray_var_tys(&mut ctx.unifier, x2_ty).0
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
 
             let x1_scalar_ty = if is_ndarray1 { dtype } else { x1_ty };
@@ -1810,7 +1812,7 @@ pub fn call_numpy_hypot<'ctx, G: CodeGenerator + ?Sized>(
             } else if is_ndarray2 {
                 unpack_ndarray_var_tys(&mut ctx.unifier, x2_ty).0
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
 
             let x1_scalar_ty = if is_ndarray1 { dtype } else { x1_ty };
@@ -1877,7 +1879,7 @@ pub fn call_numpy_nextafter<'ctx, G: CodeGenerator + ?Sized>(
             } else if is_ndarray2 {
                 unpack_ndarray_var_tys(&mut ctx.unifier, x2_ty).0
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
 
             let x1_scalar_ty = if is_ndarray1 { dtype } else { x1_ty };

nac3core/src/codegen/classes.rs

@@ -1404,7 +1404,7 @@ impl<'ctx> NDArrayValue<'ctx> {
 
     /// Returns the double-indirection pointer to the `data` array, as if by calling `getelementptr`
     /// on the field.
-    fn ptr_to_data(&self, ctx: &CodeGenContext<'ctx, '_>) -> PointerValue<'ctx> {
+    pub fn ptr_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();
 

nac3core/src/codegen/expr.rs

@@ -11,6 +11,7 @@ use crate::{
             call_expect, call_float_floor, call_float_pow, call_float_powi, call_int_smax,
             call_int_umin, call_memcpy_generic,
         },
+        macros::codegen_unreachable,
         need_sret, numpy,
         stmt::{
             gen_for_callback_incrementing, gen_if_callback, gen_if_else_expr_callback, gen_raise,
@@ -112,7 +113,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
         let obj_id = match &*self.unifier.get_ty(ty) {
             TypeEnum::TObj { obj_id, .. } => *obj_id,
             // we cannot have other types, virtual type should be handled by function calls
-            _ => unreachable!(),
+            _ => codegen_unreachable!(self),
         };
         let def = &self.top_level.definitions.read()[obj_id.0];
         let (index, value) = if let TopLevelDef::Class { fields, attributes, .. } = &*def.read() {
@@ -123,7 +124,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                 (attribute_index.0, Some(attribute_index.1 .2.clone()))
             }
         } else {
-            unreachable!()
+            codegen_unreachable!(self)
         };
         (index, value)
     }
@@ -133,7 +134,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
             TypeEnum::TObj { fields, .. } => {
                 fields.iter().find_position(|x| *x.0 == attr).unwrap().0
             }
-            _ => unreachable!(),
+            _ => codegen_unreachable!(self),
         }
     }
 
@@ -188,7 +189,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                     {
                         *params.iter().next().unwrap().1
                     }
-                    _ => unreachable!("must be option type"),
+                    _ => codegen_unreachable!(self, "must be option type"),
                 };
                 let val = self.gen_symbol_val(generator, v, ty);
                 let ptr = generator
@@ -204,7 +205,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                     {
                         *params.iter().next().unwrap().1
                     }
-                    _ => unreachable!("must be option type"),
+                    _ => codegen_unreachable!(self, "must be option type"),
                 };
                 let actual_ptr_type =
                     self.get_llvm_type(generator, ty).ptr_type(AddressSpace::default());
@@ -271,7 +272,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                 {
                     self.ctx.i64_type()
                 } else {
-                    unreachable!()
+                    codegen_unreachable!(self)
                 };
                 Some(ty.const_int(*val as u64, false).into())
             }
@@ -285,7 +286,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                 let (types, is_vararg_ctx) = if let TypeEnum::TTuple { ty, is_vararg_ctx } = &*ty {
                     (ty.clone(), *is_vararg_ctx)
                 } else {
-                    unreachable!()
+                    codegen_unreachable!(self)
                 };
                 let values = zip(types, v.iter())
                     .map_while(|(ty, v)| self.gen_const(generator, v, ty))
@@ -330,7 +331,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
 
                 None
             }
-            _ => unreachable!(),
+            _ => codegen_unreachable!(self),
         }
     }
 
@@ -344,7 +345,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
         signed: bool,
     ) -> BasicValueEnum<'ctx> {
         let (BasicValueEnum::IntValue(lhs), BasicValueEnum::IntValue(rhs)) = (lhs, rhs) else {
-            unreachable!()
+            codegen_unreachable!(self)
         };
         let float = self.ctx.f64_type();
         match (op, signed) {
@@ -419,7 +420,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
                         .build_right_shift(lhs, rhs, signed, "rshift")
                         .map(Into::into)
                         .unwrap(),
-                    _ => unreachable!(),
+                    _ => codegen_unreachable!(self),
                 }
             }
 
@@ -431,7 +432,7 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
             }
             (Operator::Pow, s) => integer_power(generator, self, lhs, rhs, s).into(),
             // special implementation?
-            (Operator::MatMult, _) => unreachable!(),
+            (Operator::MatMult, _) => codegen_unreachable!(self),
         }
     }
 
@@ -443,7 +444,8 @@ impl<'ctx, 'a> CodeGenContext<'ctx, 'a> {
         rhs: BasicValueEnum<'ctx>,
     ) -> BasicValueEnum<'ctx> {
         let (BasicValueEnum::FloatValue(lhs), BasicValueEnum::FloatValue(rhs)) = (lhs, rhs) else {
-            unreachable!(
+            codegen_unreachable!(
+                self,
                 "Expected (FloatValue, FloatValue), got ({}, {})",
                 lhs.get_type(),
                 rhs.get_type()
@@ -687,7 +689,7 @@ pub fn gen_constructor<'ctx, 'a, G: CodeGenerator>(
     def: &TopLevelDef,
     params: Vec<(Option<StrRef>, ValueEnum<'ctx>)>,
 ) -> Result<BasicValueEnum<'ctx>, String> {
-    let TopLevelDef::Class { methods, .. } = def else { unreachable!() };
+    let TopLevelDef::Class { methods, .. } = def else { codegen_unreachable!(ctx) };
 
     // TODO: what about other fields that require alloca?
     let fun_id = methods.iter().find(|method| method.0 == "__init__".into()).map(|method| method.2);
@@ -719,7 +721,7 @@ pub fn gen_func_instance<'ctx>(
         key,
     ) = fun
     else {
-        unreachable!()
+        codegen_unreachable!(ctx)
     };
 
     if let Some(sym) = instance_to_symbol.get(&key) {
@@ -751,7 +753,7 @@ pub fn gen_func_instance<'ctx>(
         .collect();
 
     let mut signature = store.from_signature(&mut ctx.unifier, &ctx.primitives, sign, &mut cache);
-    let ConcreteTypeEnum::TFunc { args, .. } = &mut signature else { unreachable!() };
+    let ConcreteTypeEnum::TFunc { args, .. } = &mut signature else { codegen_unreachable!(ctx) };
 
     if let Some(obj) = &obj {
         let zelf = store.from_unifier_type(&mut ctx.unifier, &ctx.primitives, obj.0, &mut cache);
@@ -1117,7 +1119,7 @@ pub fn gen_comprehension<'ctx, G: CodeGenerator>(
     ctx: &mut CodeGenContext<'ctx, '_>,
     expr: &Expr<Option<Type>>,
 ) -> Result<Option<BasicValueEnum<'ctx>>, String> {
-    let ExprKind::ListComp { elt, generators } = &expr.node else { unreachable!() };
+    let ExprKind::ListComp { elt, generators } = &expr.node else { codegen_unreachable!(ctx) };
 
     let current = ctx.builder.get_insert_block().unwrap().get_parent().unwrap();
 
@@ -1376,13 +1378,13 @@ pub fn gen_binop_expr_with_values<'ctx, G: CodeGenerator>(
                     if let TypeEnum::TObj { params, .. } = &*ctx.unifier.get_ty_immutable(ty1) {
                         ctx.unifier.get_representative(*params.iter().next().unwrap().1)
                     } else {
-                        unreachable!()
+                        codegen_unreachable!(ctx)
                     };
                 let elem_ty2 =
                     if let TypeEnum::TObj { params, .. } = &*ctx.unifier.get_ty_immutable(ty2) {
                         ctx.unifier.get_representative(*params.iter().next().unwrap().1)
                     } else {
-                        unreachable!()
+                        codegen_unreachable!(ctx)
                     };
                 debug_assert!(ctx.unifier.unioned(elem_ty1, elem_ty2));
 
@@ -1455,7 +1457,7 @@ pub fn gen_binop_expr_with_values<'ctx, G: CodeGenerator>(
                         {
                             *params.iter().next().unwrap().1
                         } else {
-                            unreachable!()
+                            codegen_unreachable!(ctx)
                         };
 
                         (elem_ty, left_val, right_val)
@@ -1465,12 +1467,12 @@ pub fn gen_binop_expr_with_values<'ctx, G: CodeGenerator>(
                         {
                             *params.iter().next().unwrap().1
                         } else {
-                            unreachable!()
+                            codegen_unreachable!(ctx)
                         };
 
                         (elem_ty, right_val, left_val)
                     } else {
-                        unreachable!()
+                        codegen_unreachable!(ctx)
                     };
                 let list_val =
                     ListValue::from_ptr_val(list_val.into_pointer_value(), llvm_usize, None);
@@ -1637,7 +1639,7 @@ pub fn gen_binop_expr_with_values<'ctx, G: CodeGenerator>(
     } else {
         let left_ty_enum = ctx.unifier.get_ty_immutable(left_ty.unwrap());
         let TypeEnum::TObj { fields, obj_id, .. } = left_ty_enum.as_ref() else {
-            unreachable!("must be tobj")
+            codegen_unreachable!(ctx, "must be tobj")
         };
         let (op_name, id) = {
             let normal_method_name = Binop::normal(op.base).op_info().method_name;
@@ -1658,19 +1660,19 @@ pub fn gen_binop_expr_with_values<'ctx, G: CodeGenerator>(
         } else {
             let left_enum_ty = ctx.unifier.get_ty_immutable(left_ty.unwrap());
             let TypeEnum::TObj { fields, .. } = left_enum_ty.as_ref() else {
-                unreachable!("must be tobj")
+                codegen_unreachable!(ctx, "must be tobj")
             };
 
             let fn_ty = fields.get(&op_name).unwrap().0;
             let fn_ty_enum = ctx.unifier.get_ty_immutable(fn_ty);
-            let TypeEnum::TFunc(sig) = fn_ty_enum.as_ref() else { unreachable!() };
+            let TypeEnum::TFunc(sig) = fn_ty_enum.as_ref() else { codegen_unreachable!(ctx) };
 
             sig.clone()
         };
         let fun_id = {
             let defs = ctx.top_level.definitions.read();
             let obj_def = defs.get(id.0).unwrap().read();
-            let TopLevelDef::Class { methods, .. } = &*obj_def else { unreachable!() };
+            let TopLevelDef::Class { methods, .. } = &*obj_def else { codegen_unreachable!(ctx) };
 
             methods.iter().find(|method| method.0 == op_name).unwrap().2
         };
@@ -1801,7 +1803,8 @@ pub fn gen_unaryop_expr_with_values<'ctx, G: CodeGenerator>(
             if op == ast::Unaryop::Invert {
                 ast::Unaryop::Not
             } else {
-                unreachable!(
+                codegen_unreachable!(
+                    ctx,
                     "ufunc {} not supported for ndarray[bool, N]",
                     op.op_info().method_name,
                 )
@@ -1868,8 +1871,8 @@ pub fn gen_cmpop_expr_with_values<'ctx, G: CodeGenerator>(
         {
             let llvm_usize = generator.get_size_type(ctx.ctx);
 
-            let (Some(left_ty), lhs) = left else { unreachable!() };
-            let (Some(right_ty), rhs) = comparators[0] else { unreachable!() };
+            let (Some(left_ty), lhs) = left else { codegen_unreachable!(ctx) };
+            let (Some(right_ty), rhs) = comparators[0] else { codegen_unreachable!(ctx) };
             let op = ops[0];
 
             let is_ndarray1 =
@@ -1976,7 +1979,7 @@ pub fn gen_cmpop_expr_with_values<'ctx, G: CodeGenerator>(
                 let op = match op {
                     ast::Cmpop::Eq | ast::Cmpop::Is => IntPredicate::EQ,
                     ast::Cmpop::NotEq => IntPredicate::NE,
-                    _ if left_ty == ctx.primitives.bool => unreachable!(),
+                    _ if left_ty == ctx.primitives.bool => codegen_unreachable!(ctx),
                     ast::Cmpop::Lt => {
                         if use_unsigned_ops {
                             IntPredicate::ULT
@@ -2005,7 +2008,7 @@ pub fn gen_cmpop_expr_with_values<'ctx, G: CodeGenerator>(
                             IntPredicate::SGE
                         }
                     }
-                    _ => unreachable!(),
+                    _ => codegen_unreachable!(ctx),
                 };
 
                 ctx.builder.build_int_compare(op, lhs, rhs, "cmp").unwrap()
@@ -2022,7 +2025,7 @@ pub fn gen_cmpop_expr_with_values<'ctx, G: CodeGenerator>(
                     ast::Cmpop::LtE => inkwell::FloatPredicate::OLE,
                     ast::Cmpop::Gt => inkwell::FloatPredicate::OGT,
                     ast::Cmpop::GtE => inkwell::FloatPredicate::OGE,
-                    _ => unreachable!(),
+                    _ => codegen_unreachable!(ctx),
                 };
                 ctx.builder.build_float_compare(op, lhs, rhs, "cmp").unwrap()
             } else if left_ty == ctx.primitives.str {
@@ -2154,7 +2157,7 @@ pub fn gen_cmpop_expr_with_values<'ctx, G: CodeGenerator>(
                         match (op, val) {
                             (Cmpop::Eq, true) | (Cmpop::NotEq, false) => llvm_i1.const_all_ones(),
                             (Cmpop::Eq, false) | (Cmpop::NotEq, true) => llvm_i1.const_zero(),
-                            (_, _) => unreachable!(),
+                            (_, _) => codegen_unreachable!(ctx),
                         }
                     };
 
@@ -2167,14 +2170,14 @@ pub fn gen_cmpop_expr_with_values<'ctx, G: CodeGenerator>(
                     {
                         *params.iter().next().unwrap().1
                     } else {
-                        unreachable!()
+                        codegen_unreachable!(ctx)
                     };
                     let right_elem_ty = if let TypeEnum::TObj { params, .. } =
                         &*ctx.unifier.get_ty_immutable(right_ty)
                     {
                         *params.iter().next().unwrap().1
                     } else {
-                        unreachable!()
+                        codegen_unreachable!(ctx)
                     };
 
                     if !ctx.unifier.unioned(left_elem_ty, right_elem_ty) {
@@ -2382,7 +2385,10 @@ pub fn gen_cmpop_expr_with_values<'ctx, G: CodeGenerator>(
                                 })
                                 .map(BasicValueEnum::into_int_value)?;
 
-                            Ok(ctx.builder.build_not(cmp, "").unwrap())
+                            Ok(ctx.builder.build_not(
+                                generator.bool_to_i1(ctx, cmp),
+                                "",
+                            ).unwrap())
                         },
                         |_, ctx| {
                             let bb = ctx.builder.get_insert_block().unwrap();
@@ -2511,7 +2517,7 @@ fn gen_ndarray_subscript_expr<'ctx, G: CodeGenerator>(
     let llvm_usize = generator.get_size_type(ctx.ctx);
 
     let TypeEnum::TLiteral { values, .. } = &*ctx.unifier.get_ty_immutable(ndims) else {
-        unreachable!()
+        codegen_unreachable!(ctx)
     };
 
     let ndims = values
@@ -2863,7 +2869,7 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
                         .const_null()
                         .into()
                 }
-                _ => unreachable!("must be option type"),
+                _ => codegen_unreachable!(ctx, "must be option type"),
             }
         }
         ExprKind::Name { id, .. } => match ctx.var_assignment.get(id) {
@@ -2873,29 +2879,7 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
             Some((_, Some(static_value), _)) => ValueEnum::Static(static_value.clone()),
             None => {
                 let resolver = ctx.resolver.clone();
-                if let Some(res) = resolver.get_symbol_value(*id, ctx) {
-                    res
-                } else {
-                    // Allow "raise Exception" short form
-                    let def_id = resolver.get_identifier_def(*id).map_err(|e| {
-                        format!("{} (at {})", e.iter().next().unwrap(), expr.location)
-                    })?;
-                    let def = ctx.top_level.definitions.read();
-                    if let TopLevelDef::Class { constructor, .. } = *def[def_id.0].read() {
-                        let TypeEnum::TFunc(signature) =
-                            ctx.unifier.get_ty(constructor.unwrap()).as_ref().clone()
-                        else {
-                            return Err(format!(
-                                "Failed to resolve symbol {} (at {})",
-                                id, expr.location
-                            ));
-                        };
-                        return Ok(generator
-                            .gen_call(ctx, None, (&signature, def_id), Vec::default())?
-                            .map(Into::into));
-                    }
-                    return Err(format!("Failed to resolve symbol {} (at {})", id, expr.location));
-                }
+                resolver.get_symbol_value(*id, ctx).unwrap()
             }
         },
         ExprKind::List { elts, .. } => {
@@ -2924,7 +2908,7 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
 
                     *params.iter().next().unwrap().1
                 } else {
-                    unreachable!()
+                    codegen_unreachable!(ctx)
                 };
 
                 if let TypeEnum::TVar { .. } = &*ctx.unifier.get_ty_immutable(ty) {
@@ -3018,7 +3002,9 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
 
                             return generator.gen_expr(ctx, &modified_expr);
                         }
-                        None => unreachable!("Function Type should not have attributes"),
+                        None => {
+                            codegen_unreachable!(ctx, "Function Type should not have attributes")
+                        }
                     }
                 } else if let TypeEnum::TObj { obj_id, fields, params } = &*ctx.unifier.get_ty(c) {
                     if fields.is_empty() && params.is_empty() {
@@ -3040,7 +3026,7 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
 
                                 return generator.gen_expr(ctx, &modified_expr);
                             }
-                            None => unreachable!(),
+                            None => codegen_unreachable!(ctx),
                         }
                     }
                 }
@@ -3142,7 +3128,7 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
                 }
                 (Some(a), None) => a.into(),
                 (None, Some(b)) => b.into(),
-                (None, None) => unreachable!(),
+                (None, None) => codegen_unreachable!(ctx),
             }
         }
         ExprKind::BinOp { op, left, right } => {
@@ -3232,7 +3218,9 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
                 ctx.unifier.get_call_signature(*call).unwrap()
             } else {
                 let ty = func.custom.unwrap();
-                let TypeEnum::TFunc(sign) = &*ctx.unifier.get_ty(ty) else { unreachable!() };
+                let TypeEnum::TFunc(sign) = &*ctx.unifier.get_ty(ty) else {
+                    codegen_unreachable!(ctx)
+                };
 
                 sign.clone()
             };
@@ -3251,17 +3239,26 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
                     let Some(val) = generator.gen_expr(ctx, value)? else { return Ok(None) };
 
                     // Handle Class Method calls
+                    // The attribute will be `DefinitionId` of the method if the call is to one of the parent methods
+                    let func_id = attr.to_string().parse::<usize>();
+
                     let id = if let TypeEnum::TObj { obj_id, .. } =
                         &*ctx.unifier.get_ty(value.custom.unwrap())
                     {
                         *obj_id
                     } else {
-                        unreachable!()
+                        codegen_unreachable!(ctx)
                     };
-                    let fun_id = {
+
+                    // Use the `DefinitionID` from attribute if it is available
+                    let fun_id = if let Ok(func_id) = func_id {
+                        DefinitionId(func_id)
+                    } else {
                         let defs = ctx.top_level.definitions.read();
                         let obj_def = defs.get(id.0).unwrap().read();
-                        let TopLevelDef::Class { methods, .. } = &*obj_def else { unreachable!() };
+                        let TopLevelDef::Class { methods, .. } = &*obj_def else {
+                            codegen_unreachable!(ctx)
+                        };
 
                         methods.iter().find(|method| method.0 == *attr).unwrap().2
                     };
@@ -3332,7 +3329,9 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
                                         .unwrap(),
                                 ));
                             }
-                            ValueEnum::Dynamic(_) => unreachable!("option must be static or ptr"),
+                            ValueEnum::Dynamic(_) => {
+                                codegen_unreachable!(ctx, "option must be static or ptr")
+                            }
                         }
                     }
 
@@ -3481,7 +3480,10 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
                         if let ExprKind::Constant { value: Constant::Int(v), .. } = &slice.node {
                             (*v).try_into().unwrap()
                         } else {
-                            unreachable!("tuple subscript must be const int after type check");
+                            codegen_unreachable!(
+                                ctx,
+                                "tuple subscript must be const int after type check"
+                            );
                         };
                     match generator.gen_expr(ctx, value)? {
                         Some(ValueEnum::Dynamic(v)) => {
@@ -3504,7 +3506,10 @@ pub fn gen_expr<'ctx, G: CodeGenerator>(
                         None => return Ok(None),
                     }
                 }
-                _ => unreachable!("should not be other subscriptable types after type check"),
+                _ => codegen_unreachable!(
+                    ctx,
+                    "should not be other subscriptable types after type check"
+                ),
             }
         }
         ExprKind::ListComp { .. } => {

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/mod.rs

@@ -1,28 +1,29 @@
-use crate::typecheck::typedef::Type;
+use crate::{symbol_resolver::SymbolResolver, typecheck::typedef::Type};
 
 use super::{
     classes::{
         ArrayLikeIndexer, ArrayLikeValue, ArraySliceValue, ListValue, NDArrayValue,
-        TypedArrayLikeAdapter, UntypedArrayLikeAccessor,
+        TypedArrayLikeAccessor, TypedArrayLikeAdapter, UntypedArrayLikeAccessor,
     },
-    llvm_intrinsics, CodeGenContext, CodeGenerator,
+    llvm_intrinsics,
+    macros::codegen_unreachable,
+    stmt::gen_for_callback_incrementing,
+    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::{BasicValueEnum, CallSiteValue, FloatValue, IntValue},
+    values::{BasicValue, BasicValueEnum, CallSiteValue, FloatValue, IntValue},
     AddressSpace, IntPredicate,
 };
 use itertools::Either;
 use nac3parser::ast::Expr;
 
 #[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",
@@ -38,6 +39,25 @@ 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
 }
 
@@ -55,7 +75,7 @@ pub fn integer_power<'ctx, G: CodeGenerator + ?Sized>(
         (64, 64, true) => "__nac3_int_exp_int64_t",
         (32, 32, false) => "__nac3_int_exp_uint32_t",
         (64, 64, false) => "__nac3_int_exp_uint64_t",
-        _ => unreachable!(),
+        _ => codegen_unreachable!(ctx),
     };
     let base_type = base.get_type();
     let pow_fun = ctx.module.get_function(symbol).unwrap_or_else(|| {
@@ -441,7 +461,7 @@ pub fn list_slice_assignment<'ctx, G: CodeGenerator + ?Sized>(
                     BasicTypeEnum::IntType(t) => t.size_of(),
                     BasicTypeEnum::PointerType(t) => t.size_of(),
                     BasicTypeEnum::StructType(t) => t.size_of().unwrap(),
-                    _ => unreachable!(),
+                    _ => codegen_unreachable!(ctx),
                 };
                 ctx.builder.build_int_truncate_or_bit_cast(s, int32, "size").unwrap()
             }
@@ -586,7 +606,7 @@ where
     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),
+        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()],
@@ -637,7 +657,7 @@ pub fn call_ndarray_calc_nd_indices<'ctx, G: CodeGenerator + ?Sized>(
     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),
+        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(|| {
@@ -706,7 +726,7 @@ where
     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),
+        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(|| {
@@ -774,7 +794,7 @@ pub fn call_ndarray_calc_broadcast<'ctx, G: CodeGenerator + ?Sized>(
     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),
+        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(|| {
@@ -894,7 +914,7 @@ pub fn call_ndarray_calc_broadcast_index<
     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),
+        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(|| {

nac3core/src/codegen/mod.rs

@@ -41,6 +41,7 @@ pub mod extern_fns;
 mod generator;
 pub mod irrt;
 pub mod llvm_intrinsics;
+pub mod model;
 pub mod numpy;
 pub mod stmt;
 
@@ -50,6 +51,22 @@ mod test;
 use concrete_type::{ConcreteType, ConcreteTypeEnum, ConcreteTypeStore};
 pub use generator::{CodeGenerator, DefaultCodeGenerator};
 
+mod macros {
+    /// 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 {
     pub lookup: HashMap<Vec<(usize, u64)>, usize>,

nac3core/src/codegen/model/any.rs

@@ -0,0 +1,42 @@
+use inkwell::{
+    context::Context,
+    types::{BasicType, BasicTypeEnum},
+    values::BasicValueEnum,
+};
+
+use crate::codegen::CodeGenerator;
+
+use super::*;
+
+/// A [`Model`] of any [`BasicTypeEnum`].
+///
+/// Use this when it is infeasible to use model abstractions.
+#[derive(Debug, Clone, Copy)]
+pub struct Any<'ctx>(pub BasicTypeEnum<'ctx>);
+
+impl<'ctx> Model<'ctx> for Any<'ctx> {
+    type Value = BasicValueEnum<'ctx>;
+    type Type = BasicTypeEnum<'ctx>;
+
+    fn llvm_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &G,
+        _ctx: &'ctx Context,
+    ) -> Self::Type {
+        self.0
+    }
+
+    fn check_type<T: BasicType<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &mut G,
+        _ctx: &'ctx Context,
+        ty: T,
+    ) -> Result<(), ModelError> {
+        let ty = ty.as_basic_type_enum();
+        if ty == self.0 {
+            Ok(())
+        } else {
+            Err(ModelError(format!("Expecting {}, but got {}", self.0, ty)))
+        }
+    }
+}

nac3core/src/codegen/model/array.rs

@@ -0,0 +1,147 @@
+use std::fmt;
+
+use inkwell::{
+    context::Context,
+    types::{ArrayType, BasicType, BasicTypeEnum},
+    values::{ArrayValue, IntValue},
+};
+
+use crate::codegen::{CodeGenContext, CodeGenerator};
+
+use super::*;
+
+/// Trait for Rust structs identifying length values for [`Array`].
+pub trait ArrayLen: fmt::Debug + Clone + Copy {
+    fn length(&self) -> u32;
+}
+
+/// A statically known length.
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Len<const N: u32>;
+
+/// A dynamically known length.
+#[derive(Debug, Clone, Copy)]
+pub struct AnyLen(pub u32);
+
+impl<const N: u32> ArrayLen for Len<N> {
+    fn length(&self) -> u32 {
+        N
+    }
+}
+
+impl ArrayLen for AnyLen {
+    fn length(&self) -> u32 {
+        self.0
+    }
+}
+
+/// A Model for an [`ArrayType`].
+///
+/// `Len` should be of a [`LenKind`] and `Item` should be a of [`Model`].
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Array<Len, Item> {
+    /// Length of this array.
+    pub len: Len,
+    /// [`Model`] of the array items.
+    pub item: Item,
+}
+
+impl<'ctx, Len: ArrayLen, Item: Model<'ctx>> Model<'ctx> for Array<Len, Item> {
+    type Value = ArrayValue<'ctx>;
+    type Type = ArrayType<'ctx>;
+
+    fn llvm_type<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &'ctx Context,
+    ) -> Self::Type {
+        self.item.llvm_type(generator, ctx).array_type(self.len.length())
+    }
+
+    fn check_type<T: BasicType<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        ty: T,
+    ) -> Result<(), ModelError> {
+        let ty = ty.as_basic_type_enum();
+        let BasicTypeEnum::ArrayType(ty) = ty else {
+            return Err(ModelError(format!("Expecting ArrayType, but got {ty:?}")));
+        };
+
+        if ty.len() != self.len.length() {
+            return Err(ModelError(format!(
+                "Expecting ArrayType with size {}, but got an ArrayType with size {}",
+                ty.len(),
+                self.len.length()
+            )));
+        }
+
+        self.item
+            .check_type(generator, ctx, ty.get_element_type())
+            .map_err(|err| err.under_context("an ArrayType"))?;
+
+        Ok(())
+    }
+}
+
+impl<'ctx, Len: ArrayLen, Item: Model<'ctx>> Instance<'ctx, Ptr<Array<Len, Item>>> {
+    /// Get the pointer to the `i`-th (0-based) array element.
+    pub fn gep(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        i: IntValue<'ctx>,
+    ) -> Instance<'ctx, Ptr<Item>> {
+        let zero = ctx.ctx.i32_type().const_zero();
+        let ptr = unsafe { ctx.builder.build_in_bounds_gep(self.value, &[zero, i], "").unwrap() };
+
+        unsafe { Ptr(self.model.0.item).believe_value(ptr) }
+    }
+
+    /// Like `gep` but `i` is a constant.
+    pub fn gep_const(&self, ctx: &CodeGenContext<'ctx, '_>, i: u64) -> Instance<'ctx, Ptr<Item>> {
+        assert!(
+            i < u64::from(self.model.0.len.length()),
+            "Index {i} is out of bounds. Array length = {}",
+            self.model.0.len.length()
+        );
+
+        let i = ctx.ctx.i32_type().const_int(i, false);
+        self.gep(ctx, i)
+    }
+
+    /// Convenience function equivalent to `.gep(...).load(...)`.
+    pub fn get<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        i: IntValue<'ctx>,
+    ) -> Instance<'ctx, Item> {
+        self.gep(ctx, i).load(generator, ctx)
+    }
+
+    /// Like `get` but `i` is a constant.
+    pub fn get_const<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        i: u64,
+    ) -> Instance<'ctx, Item> {
+        self.gep_const(ctx, i).load(generator, ctx)
+    }
+
+    /// Convenience function equivalent to `.gep(...).store(...)`.
+    pub fn set(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        i: IntValue<'ctx>,
+        value: Instance<'ctx, Item>,
+    ) {
+        self.gep(ctx, i).store(ctx, value);
+    }
+
+    /// Like `set` but `i` is a constant.
+    pub fn set_const(&self, ctx: &CodeGenContext<'ctx, '_>, i: u64, value: Instance<'ctx, Item>) {
+        self.gep_const(ctx, i).store(ctx, value);
+    }
+}

nac3core/src/codegen/model/core.rs

@@ -0,0 +1,207 @@
+use std::fmt;
+
+use inkwell::{context::Context, types::*, values::*};
+use itertools::Itertools;
+
+use super::*;
+use crate::codegen::{CodeGenContext, CodeGenerator};
+
+/// A error type for reporting any [`Model`]-related error (e.g., a [`BasicType`] mismatch).
+#[derive(Debug, Clone)]
+pub struct ModelError(pub String);
+
+impl ModelError {
+    /// Append a context message to the error.
+    pub(super) fn under_context(mut self, context: &str) -> Self {
+        self.0.push_str(" ... in ");
+        self.0.push_str(context);
+        self
+    }
+}
+
+/// Trait for Rust structs identifying [`BasicType`]s in the context of a known [`CodeGenerator`] and [`CodeGenContext`].
+///
+/// For instance,
+/// - [`Int<Int32>`] identifies an [`IntType`] with 32-bits.
+/// - [`Int<SizeT>`] identifies an [`IntType`] with bit-width [`CodeGenerator::get_size_type`].
+/// - [`Ptr<Int<SizeT>>`] identifies a [`PointerType`] that points to an [`IntType`] with bit-width [`CodeGenerator::get_size_type`].
+/// - [`Int<AnyInt>`] identifies an [`IntType`] with bit-width of whatever is set in the [`AnyInt`] object.
+/// - [`Any`] identifies a [`BasicType`] set in the [`Any`] object itself.
+///
+/// You can get the [`BasicType`] out of a model with [`Model::get_type`].
+///
+/// Furthermore, [`Instance<'ctx, M>`] is a simple structure that carries a [`BasicValue`] with [`BasicType`] identified by model `M`.
+///
+/// The main purpose of this abstraction is to have a more Rust type-safe way to use Inkwell and give type-hints for programmers.
+///
+/// ### Notes on `Default` trait
+///
+/// For some models like [`Int<Int32>`] or [`Int<SizeT>`], they have a [`Default`] trait since just by looking at their types, it is possible
+/// to tell the [`BasicType`]s they are identifying.
+///
+/// This can be used to create strongly-typed interfaces accepting only values of a specific [`BasicType`] without having to worry about
+/// writing debug assertions to check, for example, if the programmer has passed in an [`IntValue`] with the wrong bit-width.
+/// ```ignore
+/// fn give_me_i32_and_get_a_size_t_back<'ctx>(i32: Instance<'ctx, Int<Int32>>) -> Instance<'ctx, Int<SizeT>> {
+///     // code...
+/// }
+/// ```
+///
+/// ### Notes on converting between Inkwell and model/ge.
+///
+/// Suppose you have an [`IntValue`], and you want to pass it into a function that takes a [`Instance<'ctx, Int<Int32>>`]. You can do use
+/// [`Model::check_value`] or [`Model::believe_value`].
+/// ```ignore
+/// let my_value: IntValue<'ctx>;
+///
+/// let my_value = Int(Int32).check_value(my_value).unwrap(); // Panics if `my_value` is not 32-bit with a descriptive error message.
+///
+/// // or, if you are absolutely certain that `my_value` is 32-bit and doing extra checks is a waste of time:
+/// let my_value = Int(Int32).believe_value(my_value);
+/// ```
+pub trait Model<'ctx>: fmt::Debug + Clone + Copy {
+    /// The [`BasicType`] *variant* this model is identifying.
+    type Type: BasicType<'ctx>;
+
+    /// The [`BasicValue`] type of the [`BasicType`] of this model.
+    type Value: BasicValue<'ctx> + TryFrom<BasicValueEnum<'ctx>>;
+
+    /// Return the [`BasicType`] of this model.
+    #[must_use]
+    fn llvm_type<G: CodeGenerator + ?Sized>(&self, generator: &G, ctx: &'ctx Context)
+        -> Self::Type;
+
+    /// Get the number of bytes of the [`BasicType`] of this model.
+    fn size_of<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+    ) -> IntValue<'ctx> {
+        self.llvm_type(generator, ctx).size_of().unwrap()
+    }
+
+    /// Check if a [`BasicType`] matches the [`BasicType`] of this model.
+    fn check_type<T: BasicType<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        ty: T,
+    ) -> Result<(), ModelError>;
+
+    /// Create an instance from a value.
+    ///
+    /// # Safety
+    ///
+    /// Caller must make sure the type of `value` and the type of this `model` are equivalent.
+    #[must_use]
+    unsafe fn believe_value(&self, value: Self::Value) -> Instance<'ctx, Self> {
+        Instance { model: *self, value }
+    }
+
+    /// Check if a [`BasicValue`]'s type is equivalent to the type of this model.
+    /// Wrap the [`BasicValue`] into an [`Instance`] if it is.
+    fn check_value<V: BasicValue<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        value: V,
+    ) -> Result<Instance<'ctx, Self>, ModelError> {
+        let value = value.as_basic_value_enum();
+        self.check_type(generator, ctx, value.get_type())
+            .map_err(|err| err.under_context(format!("the value {value:?}").as_str()))?;
+
+        let Ok(value) = Self::Value::try_from(value) else {
+            unreachable!("check_type() has bad implementation")
+        };
+        unsafe { Ok(self.believe_value(value)) }
+    }
+
+    // Allocate a value on the stack and return its pointer.
+    fn alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) -> Instance<'ctx, Ptr<Self>> {
+        let p = ctx.builder.build_alloca(self.llvm_type(generator, ctx.ctx), "").unwrap();
+        unsafe { Ptr(*self).believe_value(p) }
+    }
+
+    // Allocate an array on the stack and return its pointer.
+    fn array_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        len: IntValue<'ctx>,
+    ) -> Instance<'ctx, Ptr<Self>> {
+        let p =
+            ctx.builder.build_array_alloca(self.llvm_type(generator, ctx.ctx), len, "").unwrap();
+        unsafe { Ptr(*self).believe_value(p) }
+    }
+
+    fn var_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        name: Option<&str>,
+    ) -> Result<Instance<'ctx, Ptr<Self>>, String> {
+        let ty = self.llvm_type(generator, ctx.ctx).as_basic_type_enum();
+        let p = generator.gen_var_alloc(ctx, ty, name)?;
+        unsafe { Ok(Ptr(*self).believe_value(p)) }
+    }
+
+    fn array_var_alloca<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &mut CodeGenContext<'ctx, '_>,
+        len: IntValue<'ctx>,
+        name: Option<&'ctx str>,
+    ) -> Result<Instance<'ctx, Ptr<Self>>, String> {
+        // TODO: Remove ArraySliceValue
+        let ty = self.llvm_type(generator, ctx.ctx).as_basic_type_enum();
+        let p = generator.gen_array_var_alloc(ctx, ty, len, name)?;
+        unsafe { Ok(Ptr(*self).believe_value(PointerValue::from(p))) }
+    }
+
+    /// Allocate a constant array.
+    fn const_array<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        values: &[Instance<'ctx, Self>],
+    ) -> Instance<'ctx, Array<AnyLen, Self>> {
+        macro_rules! make {
+            ($t:expr, $into_value:expr) => {
+                $t.const_array(
+                    &values
+                        .iter()
+                        .map(|x| $into_value(x.value.as_basic_value_enum()))
+                        .collect_vec(),
+                )
+            };
+        }
+
+        let value = match self.llvm_type(generator, ctx).as_basic_type_enum() {
+            BasicTypeEnum::ArrayType(t) => make!(t, BasicValueEnum::into_array_value),
+            BasicTypeEnum::IntType(t) => make!(t, BasicValueEnum::into_int_value),
+            BasicTypeEnum::FloatType(t) => make!(t, BasicValueEnum::into_float_value),
+            BasicTypeEnum::PointerType(t) => make!(t, BasicValueEnum::into_pointer_value),
+            BasicTypeEnum::StructType(t) => make!(t, BasicValueEnum::into_struct_value),
+            BasicTypeEnum::VectorType(t) => make!(t, BasicValueEnum::into_vector_value),
+        };
+
+        Array { len: AnyLen(values.len() as u32), item: *self }
+            .check_value(generator, ctx, value)
+            .unwrap()
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct Instance<'ctx, M: Model<'ctx>> {
+    /// The model of this instance.
+    pub model: M,
+
+    /// The value of this instance.
+    ///
+    /// It is guaranteed the [`BasicType`] of `value` is consistent with that of `model`.
+    pub value: M::Value,
+}

nac3core/src/codegen/model/float.rs

@@ -0,0 +1,94 @@
+use std::fmt;
+
+use inkwell::{
+    context::Context,
+    types::{BasicType, FloatType},
+    values::FloatValue,
+};
+
+use crate::codegen::CodeGenerator;
+
+use super::*;
+
+pub trait FloatKind<'ctx>: fmt::Debug + Clone + Copy {
+    fn get_float_type<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &'ctx Context,
+    ) -> FloatType<'ctx>;
+}
+
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Float32;
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Float64;
+
+impl<'ctx> FloatKind<'ctx> for Float32 {
+    fn get_float_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &G,
+        ctx: &'ctx Context,
+    ) -> FloatType<'ctx> {
+        ctx.f32_type()
+    }
+}
+
+impl<'ctx> FloatKind<'ctx> for Float64 {
+    fn get_float_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &G,
+        ctx: &'ctx Context,
+    ) -> FloatType<'ctx> {
+        ctx.f64_type()
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct AnyFloat<'ctx>(FloatType<'ctx>);
+
+impl<'ctx> FloatKind<'ctx> for AnyFloat<'ctx> {
+    fn get_float_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &G,
+        _ctx: &'ctx Context,
+    ) -> FloatType<'ctx> {
+        self.0
+    }
+}
+
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Float<N>(pub N);
+
+impl<'ctx, N: FloatKind<'ctx>> Model<'ctx> for Float<N> {
+    type Value = FloatValue<'ctx>;
+    type Type = FloatType<'ctx>;
+
+    fn llvm_type<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &'ctx Context,
+    ) -> Self::Type {
+        self.0.get_float_type(generator, ctx)
+    }
+
+    fn check_type<T: BasicType<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        ty: T,
+    ) -> Result<(), ModelError> {
+        let ty = ty.as_basic_type_enum();
+        let Ok(ty) = FloatType::try_from(ty) else {
+            return Err(ModelError(format!("Expecting FloatType, but got {ty:?}")));
+        };
+
+        let exp_ty = self.0.get_float_type(generator, ctx);
+
+        // TODO: Inkwell does not have get_bit_width for FloatType?
+        if ty != exp_ty {
+            return Err(ModelError(format!("Expecting {exp_ty:?}, but got {ty:?}")));
+        }
+
+        Ok(())
+    }
+}

nac3core/src/codegen/model/function.rs

@@ -0,0 +1,122 @@
+use inkwell::{
+    attributes::{Attribute, AttributeLoc},
+    types::{BasicMetadataTypeEnum, BasicType, FunctionType},
+    values::{AnyValue, BasicMetadataValueEnum, BasicValue, BasicValueEnum, CallSiteValue},
+};
+use itertools::Itertools;
+
+use crate::codegen::{CodeGenContext, CodeGenerator};
+
+use super::*;
+
+#[derive(Debug, Clone, Copy)]
+struct Arg<'ctx> {
+    ty: BasicMetadataTypeEnum<'ctx>,
+    val: BasicMetadataValueEnum<'ctx>,
+}
+
+/// A convenience structure to construct & call an LLVM function.
+///
+/// ### Usage
+///
+/// The syntax is like this:
+/// ```ignore
+/// let result = CallFunction::begin("my_function_name")
+///   .attrs(...)
+///   .arg(arg1)
+///   .arg(arg2)
+///   .arg(arg3)
+///   .returning("my_function_result", Int32);
+/// ```
+///
+/// The function `my_function_name` is called when `.returning()` (or its variants) is called, returning
+/// the result as an `Instance<'ctx, Int<Int32>>`.
+///
+/// If `my_function_name` has not been declared in `ctx.module`, once `.returning()` is called, a function
+/// declaration of `my_function_name` is added to `ctx.module`, where the [`FunctionType`] is deduced from
+/// the argument types and returning type.
+pub struct FnCall<'ctx, 'a, 'b, 'c, 'd, G: CodeGenerator + ?Sized> {
+    generator: &'d mut G,
+    ctx: &'b CodeGenContext<'ctx, 'a>,
+    /// Function name
+    name: &'c str,
+    /// Call arguments
+    args: Vec<Arg<'ctx>>,
+    /// LLVM function Attributes
+    attrs: Vec<&'static str>,
+}
+
+impl<'ctx, 'a, 'b, 'c, 'd, G: CodeGenerator + ?Sized> FnCall<'ctx, 'a, 'b, 'c, 'd, G> {
+    pub fn builder(generator: &'d mut G, ctx: &'b CodeGenContext<'ctx, 'a>, name: &'c str) -> Self {
+        FnCall { generator, ctx, name, args: Vec::new(), attrs: Vec::new() }
+    }
+
+    /// Push a list of LLVM function attributes to the function declaration.
+    #[must_use]
+    pub fn attrs(mut self, attrs: Vec<&'static str>) -> Self {
+        self.attrs = attrs;
+        self
+    }
+
+    /// Push a call argument to the function call.
+    #[allow(clippy::needless_pass_by_value)]
+    #[must_use]
+    pub fn arg<M: Model<'ctx>>(mut self, arg: Instance<'ctx, M>) -> Self {
+        let arg = Arg {
+            ty: arg.model.llvm_type(self.generator, self.ctx.ctx).as_basic_type_enum().into(),
+            val: arg.value.as_basic_value_enum().into(),
+        };
+        self.args.push(arg);
+        self
+    }
+
+    /// Call the function and expect the function to return a value of type of `return_model`.
+    #[must_use]
+    pub fn returning<M: Model<'ctx>>(self, name: &str, return_model: M) -> Instance<'ctx, M> {
+        let ret_ty = return_model.llvm_type(self.generator, self.ctx.ctx);
+
+        let ret = self.call(|tys| ret_ty.fn_type(tys, false), name);
+        let ret = BasicValueEnum::try_from(ret.as_any_value_enum()).unwrap(); // Must work
+        let ret = return_model.check_value(self.generator, self.ctx.ctx, ret).unwrap(); // Must work
+        ret
+    }
+
+    /// Like [`CallFunction::returning_`] but `return_model` is automatically inferred.
+    #[must_use]
+    pub fn returning_auto<M: Model<'ctx> + Default>(self, name: &str) -> Instance<'ctx, M> {
+        self.returning(name, M::default())
+    }
+
+    /// Call the function and expect the function to return a void-type.
+    pub fn returning_void(self) {
+        let ret_ty = self.ctx.ctx.void_type();
+
+        let _ = self.call(|tys| ret_ty.fn_type(tys, false), "");
+    }
+
+    fn call<F>(&self, make_fn_type: F, return_value_name: &str) -> CallSiteValue<'ctx>
+    where
+        F: FnOnce(&[BasicMetadataTypeEnum<'ctx>]) -> FunctionType<'ctx>,
+    {
+        // Get the LLVM function.
+        let func = self.ctx.module.get_function(self.name).unwrap_or_else(|| {
+            // Declare the function if it doesn't exist.
+            let tys = self.args.iter().map(|arg| arg.ty).collect_vec();
+
+            let func_type = make_fn_type(&tys);
+            let func = self.ctx.module.add_function(self.name, func_type, None);
+
+            for attr in &self.attrs {
+                func.add_attribute(
+                    AttributeLoc::Function,
+                    self.ctx.ctx.create_enum_attribute(Attribute::get_named_enum_kind_id(attr), 0),
+                );
+            }
+
+            func
+        });
+
+        let vals = self.args.iter().map(|arg| arg.val).collect_vec();
+        self.ctx.builder.build_call(func, &vals, return_value_name).unwrap()
+    }
+}

nac3core/src/codegen/model/int.rs

@@ -0,0 +1,422 @@
+use std::{cmp::Ordering, fmt};
+
+use inkwell::{
+    context::Context,
+    types::{BasicType, IntType},
+    values::IntValue,
+    IntPredicate,
+};
+
+use crate::codegen::{CodeGenContext, CodeGenerator};
+
+use super::*;
+
+pub trait IntKind<'ctx>: fmt::Debug + Clone + Copy {
+    fn get_int_type<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &'ctx Context,
+    ) -> IntType<'ctx>;
+}
+
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Bool;
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Byte;
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Int32;
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Int64;
+#[derive(Debug, Clone, Copy, Default)]
+pub struct SizeT;
+
+impl<'ctx> IntKind<'ctx> for Bool {
+    fn get_int_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &G,
+        ctx: &'ctx Context,
+    ) -> IntType<'ctx> {
+        ctx.bool_type()
+    }
+}
+
+impl<'ctx> IntKind<'ctx> for Byte {
+    fn get_int_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &G,
+        ctx: &'ctx Context,
+    ) -> IntType<'ctx> {
+        ctx.i8_type()
+    }
+}
+
+impl<'ctx> IntKind<'ctx> for Int32 {
+    fn get_int_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &G,
+        ctx: &'ctx Context,
+    ) -> IntType<'ctx> {
+        ctx.i32_type()
+    }
+}
+
+impl<'ctx> IntKind<'ctx> for Int64 {
+    fn get_int_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &G,
+        ctx: &'ctx Context,
+    ) -> IntType<'ctx> {
+        ctx.i64_type()
+    }
+}
+
+impl<'ctx> IntKind<'ctx> for SizeT {
+    fn get_int_type<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &'ctx Context,
+    ) -> IntType<'ctx> {
+        generator.get_size_type(ctx)
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct AnyInt<'ctx>(pub IntType<'ctx>);
+
+impl<'ctx> IntKind<'ctx> for AnyInt<'ctx> {
+    fn get_int_type<G: CodeGenerator + ?Sized>(
+        &self,
+        _generator: &G,
+        _ctx: &'ctx Context,
+    ) -> IntType<'ctx> {
+        self.0
+    }
+}
+
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Int<N>(pub N);
+
+impl<'ctx, N: IntKind<'ctx>> Model<'ctx> for Int<N> {
+    type Value = IntValue<'ctx>;
+    type Type = IntType<'ctx>;
+
+    fn llvm_type<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &'ctx Context,
+    ) -> Self::Type {
+        self.0.get_int_type(generator, ctx)
+    }
+
+    fn check_type<T: BasicType<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        ty: T,
+    ) -> Result<(), ModelError> {
+        let ty = ty.as_basic_type_enum();
+        let Ok(ty) = IntType::try_from(ty) else {
+            return Err(ModelError(format!("Expecting IntType, but got {ty:?}")));
+        };
+
+        let exp_ty = self.0.get_int_type(generator, ctx);
+        if ty.get_bit_width() != exp_ty.get_bit_width() {
+            return Err(ModelError(format!(
+                "Expecting IntType to have {} bit(s), but got {} bit(s)",
+                exp_ty.get_bit_width(),
+                ty.get_bit_width()
+            )));
+        }
+
+        Ok(())
+    }
+}
+
+impl<'ctx, N: IntKind<'ctx>> Int<N> {
+    pub fn const_int<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        value: u64,
+        sign_extend: bool,
+    ) -> Instance<'ctx, Self> {
+        let value = self.llvm_type(generator, ctx).const_int(value, sign_extend);
+        unsafe { self.believe_value(value) }
+    }
+
+    pub fn const_0<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+    ) -> Instance<'ctx, Self> {
+        let value = self.llvm_type(generator, ctx).const_zero();
+        unsafe { self.believe_value(value) }
+    }
+
+    pub fn const_1<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+    ) -> Instance<'ctx, Self> {
+        self.const_int(generator, ctx, 1, false)
+    }
+
+    pub fn const_all_ones<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+    ) -> Instance<'ctx, Self> {
+        let value = self.llvm_type(generator, ctx).const_all_ones();
+        unsafe { self.believe_value(value) }
+    }
+
+    pub fn s_extend_or_bit_cast<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> Instance<'ctx, Self> {
+        assert!(
+            value.get_type().get_bit_width()
+                <= self.0.get_int_type(generator, ctx.ctx).get_bit_width()
+        );
+        let value = ctx
+            .builder
+            .build_int_s_extend_or_bit_cast(value, self.llvm_type(generator, ctx.ctx), "")
+            .unwrap();
+        unsafe { self.believe_value(value) }
+    }
+
+    pub fn s_extend<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> Instance<'ctx, Self> {
+        assert!(
+            value.get_type().get_bit_width()
+                < self.0.get_int_type(generator, ctx.ctx).get_bit_width()
+        );
+        let value =
+            ctx.builder.build_int_s_extend(value, self.llvm_type(generator, ctx.ctx), "").unwrap();
+        unsafe { self.believe_value(value) }
+    }
+
+    pub fn z_extend_or_bit_cast<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> Instance<'ctx, Self> {
+        assert!(
+            value.get_type().get_bit_width()
+                <= self.0.get_int_type(generator, ctx.ctx).get_bit_width()
+        );
+        let value = ctx
+            .builder
+            .build_int_z_extend_or_bit_cast(value, self.llvm_type(generator, ctx.ctx), "")
+            .unwrap();
+        unsafe { self.believe_value(value) }
+    }
+
+    pub fn z_extend<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> Instance<'ctx, Self> {
+        assert!(
+            value.get_type().get_bit_width()
+                < self.0.get_int_type(generator, ctx.ctx).get_bit_width()
+        );
+        let value =
+            ctx.builder.build_int_z_extend(value, self.llvm_type(generator, ctx.ctx), "").unwrap();
+        unsafe { self.believe_value(value) }
+    }
+
+    pub fn truncate_or_bit_cast<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> Instance<'ctx, Self> {
+        assert!(
+            value.get_type().get_bit_width()
+                >= self.0.get_int_type(generator, ctx.ctx).get_bit_width()
+        );
+        let value = ctx
+            .builder
+            .build_int_truncate_or_bit_cast(value, self.llvm_type(generator, ctx.ctx), "")
+            .unwrap();
+        unsafe { self.believe_value(value) }
+    }
+
+    pub fn truncate<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> Instance<'ctx, Self> {
+        assert!(
+            value.get_type().get_bit_width()
+                > self.0.get_int_type(generator, ctx.ctx).get_bit_width()
+        );
+        let value =
+            ctx.builder.build_int_truncate(value, self.llvm_type(generator, ctx.ctx), "").unwrap();
+        unsafe { self.believe_value(value) }
+    }
+
+    /// `sext` or `trunc` an int to this model's int type. Does nothing if equal bit-widths.
+    pub fn s_extend_or_truncate<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> Instance<'ctx, Self> {
+        let their_width = value.get_type().get_bit_width();
+        let our_width = self.0.get_int_type(generator, ctx.ctx).get_bit_width();
+        match their_width.cmp(&our_width) {
+            Ordering::Less => self.s_extend(generator, ctx, value),
+            Ordering::Equal => unsafe { self.believe_value(value) },
+            Ordering::Greater => self.truncate(generator, ctx, value),
+        }
+    }
+
+    /// `zext` or `trunc` an int to this model's int type. Does nothing if equal bit-widths.
+    pub fn z_extend_or_truncate<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        value: IntValue<'ctx>,
+    ) -> Instance<'ctx, Self> {
+        let their_width = value.get_type().get_bit_width();
+        let our_width = self.0.get_int_type(generator, ctx.ctx).get_bit_width();
+        match their_width.cmp(&our_width) {
+            Ordering::Less => self.z_extend(generator, ctx, value),
+            Ordering::Equal => unsafe { self.believe_value(value) },
+            Ordering::Greater => self.truncate(generator, ctx, value),
+        }
+    }
+}
+
+impl Int<Bool> {
+    #[must_use]
+    pub fn const_false<'ctx, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+    ) -> Instance<'ctx, Self> {
+        self.const_int(generator, ctx, 0, false)
+    }
+
+    #[must_use]
+    pub fn const_true<'ctx, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+    ) -> Instance<'ctx, Self> {
+        self.const_int(generator, ctx, 1, false)
+    }
+}
+
+impl<'ctx, N: IntKind<'ctx>> Instance<'ctx, Int<N>> {
+    pub fn s_extend_or_bit_cast<NewN: IntKind<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        to_int_kind: NewN,
+    ) -> Instance<'ctx, Int<NewN>> {
+        Int(to_int_kind).s_extend_or_bit_cast(generator, ctx, self.value)
+    }
+
+    pub fn s_extend<NewN: IntKind<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        to_int_kind: NewN,
+    ) -> Instance<'ctx, Int<NewN>> {
+        Int(to_int_kind).s_extend(generator, ctx, self.value)
+    }
+
+    pub fn z_extend_or_bit_cast<NewN: IntKind<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        to_int_kind: NewN,
+    ) -> Instance<'ctx, Int<NewN>> {
+        Int(to_int_kind).z_extend_or_bit_cast(generator, ctx, self.value)
+    }
+
+    pub fn z_extend<NewN: IntKind<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        to_int_kind: NewN,
+    ) -> Instance<'ctx, Int<NewN>> {
+        Int(to_int_kind).z_extend(generator, ctx, self.value)
+    }
+
+    pub fn truncate_or_bit_cast<NewN: IntKind<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        to_int_kind: NewN,
+    ) -> Instance<'ctx, Int<NewN>> {
+        Int(to_int_kind).truncate_or_bit_cast(generator, ctx, self.value)
+    }
+
+    pub fn truncate<NewN: IntKind<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        to_int_kind: NewN,
+    ) -> Instance<'ctx, Int<NewN>> {
+        Int(to_int_kind).truncate(generator, ctx, self.value)
+    }
+
+    pub fn s_extend_or_truncate<NewN: IntKind<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        to_int_kind: NewN,
+    ) -> Instance<'ctx, Int<NewN>> {
+        Int(to_int_kind).s_extend_or_truncate(generator, ctx, self.value)
+    }
+
+    pub fn z_extend_or_truncate<NewN: IntKind<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        to_int_kind: NewN,
+    ) -> Instance<'ctx, Int<NewN>> {
+        Int(to_int_kind).z_extend_or_truncate(generator, ctx, self.value)
+    }
+
+    #[must_use]
+    pub fn add(&self, ctx: &CodeGenContext<'ctx, '_>, other: Self) -> Self {
+        let value = ctx.builder.build_int_add(self.value, other.value, "").unwrap();
+        unsafe { self.model.believe_value(value) }
+    }
+
+    #[must_use]
+    pub fn sub(&self, ctx: &CodeGenContext<'ctx, '_>, other: Self) -> Self {
+        let value = ctx.builder.build_int_sub(self.value, other.value, "").unwrap();
+        unsafe { self.model.believe_value(value) }
+    }
+
+    #[must_use]
+    pub fn mul(&self, ctx: &CodeGenContext<'ctx, '_>, other: Self) -> Self {
+        let value = ctx.builder.build_int_mul(self.value, other.value, "").unwrap();
+        unsafe { self.model.believe_value(value) }
+    }
+
+    pub fn compare(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        op: IntPredicate,
+        other: Self,
+    ) -> Instance<'ctx, Int<Bool>> {
+        let value = ctx.builder.build_int_compare(op, self.value, other.value, "").unwrap();
+        unsafe { Int(Bool).believe_value(value) }
+    }
+}

nac3core/src/codegen/model/mod.rs

@@ -0,0 +1,16 @@
+mod any;
+mod array;
+mod core;
+mod float;
+pub mod function;
+mod int;
+mod ptr;
+mod structure;
+
+pub use any::*;
+pub use array::*;
+pub use core::*;
+pub use float::*;
+pub use int::*;
+pub use ptr::*;
+pub use structure::*;

nac3core/src/codegen/model/ptr.rs

@@ -0,0 +1,214 @@
+use inkwell::{
+    context::Context,
+    types::{BasicType, BasicTypeEnum, PointerType},
+    values::{IntValue, PointerValue},
+    AddressSpace,
+};
+
+use crate::codegen::{llvm_intrinsics::call_memcpy_generic, CodeGenContext, CodeGenerator};
+
+use super::*;
+
+/// A model for [`PointerType`].
+///
+/// `Item` is the element type this pointer is pointing to, and should be of a [`Model`].
+///
+// TODO: LLVM 15: `Item` is a Rust type-hint for the LLVM type of value the `.store()/.load()` family
+// of functions return. If a truly opaque pointer is needed, tell the programmer to use `OpaquePtr`.
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Ptr<Item>(pub Item);
+
+/// An opaque pointer. Like [`Ptr`] but without any Rust type-hints about its element type.
+///
+/// `.load()/.store()` is not available for [`Instance`]s of opaque pointers.
+pub type OpaquePtr = Ptr<()>;
+
+// TODO: LLVM 15: `Item: Model<'ctx>` don't even need to be a model anymore. It will only be
+// a type-hint for the `.load()/.store()` functions for the `pointee_ty`.
+//
+// See https://thedan64.github.io/inkwell/inkwell/builder/struct.Builder.html#method.build_load.
+impl<'ctx, Item: Model<'ctx>> Model<'ctx> for Ptr<Item> {
+    type Value = PointerValue<'ctx>;
+    type Type = PointerType<'ctx>;
+
+    fn llvm_type<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &'ctx Context,
+    ) -> Self::Type {
+        // TODO: LLVM 15: ctx.ptr_type(AddressSpace::default())
+        self.0.llvm_type(generator, ctx).ptr_type(AddressSpace::default())
+    }
+
+    fn check_type<T: BasicType<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        ty: T,
+    ) -> Result<(), ModelError> {
+        let ty = ty.as_basic_type_enum();
+        let Ok(ty) = PointerType::try_from(ty) else {
+            return Err(ModelError(format!("Expecting PointerType, but got {ty:?}")));
+        };
+
+        let elem_ty = ty.get_element_type();
+        let Ok(elem_ty) = BasicTypeEnum::try_from(elem_ty) else {
+            return Err(ModelError(format!(
+                "Expecting pointer element type to be a BasicTypeEnum, but got {elem_ty:?}"
+            )));
+        };
+
+        // TODO: inkwell `get_element_type()` will be deprecated.
+        // Remove the check for `get_element_type()` when the time comes.
+        self.0
+            .check_type(generator, ctx, elem_ty)
+            .map_err(|err| err.under_context("a PointerType"))?;
+
+        Ok(())
+    }
+}
+
+impl<'ctx, Item: Model<'ctx>> Ptr<Item> {
+    /// Return a ***constant*** nullptr.
+    pub fn nullptr<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+    ) -> Instance<'ctx, Ptr<Item>> {
+        let ptr = self.llvm_type(generator, ctx).const_null();
+        unsafe { self.believe_value(ptr) }
+    }
+
+    /// Cast a pointer into this model with [`inkwell::builder::Builder::build_pointer_cast`]
+    pub fn pointer_cast<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        ptr: PointerValue<'ctx>,
+    ) -> Instance<'ctx, Ptr<Item>> {
+        // TODO: LLVM 15: Write in an impl where `Item` does not have to be `Model<'ctx>`.
+        // TODO: LLVM 15: This function will only have to be:
+        // ```
+        // return self.believe_value(ptr);
+        // ```
+        let t = self.llvm_type(generator, ctx.ctx);
+        let ptr = ctx.builder.build_pointer_cast(ptr, t, "").unwrap();
+        unsafe { self.believe_value(ptr) }
+    }
+}
+
+impl<'ctx, Item: Model<'ctx>> Instance<'ctx, Ptr<Item>> {
+    /// Offset the pointer by [`inkwell::builder::Builder::build_in_bounds_gep`].
+    #[must_use]
+    pub fn offset(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        offset: IntValue<'ctx>,
+    ) -> Instance<'ctx, Ptr<Item>> {
+        let p = unsafe { ctx.builder.build_in_bounds_gep(self.value, &[offset], "").unwrap() };
+        unsafe { self.model.believe_value(p) }
+    }
+
+    /// Offset the pointer by [`inkwell::builder::Builder::build_in_bounds_gep`] by a constant offset.
+    #[must_use]
+    pub fn offset_const(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        offset: i64,
+    ) -> Instance<'ctx, Ptr<Item>> {
+        let offset = ctx.ctx.i32_type().const_int(offset as u64, true);
+        self.offset(ctx, offset)
+    }
+
+    pub fn set_index(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        index: IntValue<'ctx>,
+        value: Instance<'ctx, Item>,
+    ) {
+        self.offset(ctx, index).store(ctx, value);
+    }
+
+    pub fn set_index_const(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        index: i64,
+        value: Instance<'ctx, Item>,
+    ) {
+        self.offset_const(ctx, index).store(ctx, value);
+    }
+
+    pub fn get_index<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        index: IntValue<'ctx>,
+    ) -> Instance<'ctx, Item> {
+        self.offset(ctx, index).load(generator, ctx)
+    }
+
+    pub fn get_index_const<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        index: i64,
+    ) -> Instance<'ctx, Item> {
+        self.offset_const(ctx, index).load(generator, ctx)
+    }
+
+    /// Load the value with [`inkwell::builder::Builder::build_load`].
+    pub fn load<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+    ) -> Instance<'ctx, Item> {
+        let value = ctx.builder.build_load(self.value, "").unwrap();
+        self.model.0.check_value(generator, ctx.ctx, value).unwrap() // If unwrap() panics, there is a logic error.
+    }
+
+    /// Store a value with [`inkwell::builder::Builder::build_store`].
+    pub fn store(&self, ctx: &CodeGenContext<'ctx, '_>, value: Instance<'ctx, Item>) {
+        ctx.builder.build_store(self.value, value.value).unwrap();
+    }
+
+    /// Return a casted pointer of element type `NewElement` with [`inkwell::builder::Builder::build_pointer_cast`].
+    pub fn pointer_cast<NewItem: Model<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        new_item: NewItem,
+    ) -> Instance<'ctx, Ptr<NewItem>> {
+        // TODO: LLVM 15: Write in an impl where `Item` does not have to be `Model<'ctx>`.
+        Ptr(new_item).pointer_cast(generator, ctx, self.value)
+    }
+
+    /// Check if the pointer is null with [`inkwell::builder::Builder::build_is_null`].
+    pub fn is_null(&self, ctx: &CodeGenContext<'ctx, '_>) -> Instance<'ctx, Int<Bool>> {
+        let value = ctx.builder.build_is_null(self.value, "").unwrap();
+        unsafe { Int(Bool).believe_value(value) }
+    }
+
+    /// Check if the pointer is not null with [`inkwell::builder::Builder::build_is_not_null`].
+    pub fn is_not_null(&self, ctx: &CodeGenContext<'ctx, '_>) -> Instance<'ctx, Int<Bool>> {
+        let value = ctx.builder.build_is_not_null(self.value, "").unwrap();
+        unsafe { Int(Bool).believe_value(value) }
+    }
+
+    /// `memcpy` from another pointer.
+    pub fn copy_from<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        source: Self,
+        num_items: IntValue<'ctx>,
+    ) {
+        // Force extend `num_items` and `itemsize` to `i64` so their types would match.
+        let itemsize = self.model.size_of(generator, ctx.ctx);
+        let itemsize = Int(SizeT).z_extend_or_truncate(generator, ctx, itemsize);
+        let num_items = Int(SizeT).z_extend_or_truncate(generator, ctx, num_items);
+        let totalsize = itemsize.mul(ctx, num_items);
+
+        let is_volatile = ctx.ctx.bool_type().const_zero(); // is_volatile = false
+        call_memcpy_generic(ctx, self.value, source.value, totalsize.value, is_volatile);
+    }
+}

nac3core/src/codegen/model/structure.rs

@@ -0,0 +1,364 @@
+use std::fmt;
+
+use inkwell::{
+    context::Context,
+    types::{BasicType, BasicTypeEnum, StructType},
+    values::{BasicValueEnum, StructValue},
+};
+
+use crate::codegen::{CodeGenContext, CodeGenerator};
+
+use super::*;
+
+/// A traveral that traverses a Rust `struct` that is used to declare an LLVM's struct's field types.
+pub trait FieldTraversal<'ctx> {
+    /// Output type of [`FieldTraversal::add`].
+    type Output<M>;
+
+    /// Traverse through the type of a declared field and do something with it.
+    ///
+    /// * `name` - The cosmetic name of the LLVM field. Used for debugging.
+    /// * `model` - The [`Model`] representing the LLVM type of this field.
+    fn add<M: Model<'ctx>>(&mut self, name: &'static str, model: M) -> Self::Output<M>;
+
+    /// Like [`FieldTraversal::add`] but [`Model`] is automatically inferred from its [`Default`] trait.
+    fn add_auto<M: Model<'ctx> + Default>(&mut self, name: &'static str) -> Self::Output<M> {
+        self.add(name, M::default())
+    }
+}
+
+/// Descriptor of an LLVM struct field.
+#[derive(Debug, Clone, Copy)]
+pub struct GepField<M> {
+    /// The GEP index of this field. This is the index to use with `build_gep`.
+    pub gep_index: u32,
+    /// The cosmetic name of this field.
+    pub name: &'static str,
+    /// The [`Model`] of this field's type.
+    pub model: M,
+}
+
+/// A traversal to calculate the GEP index of fields.
+pub struct GepFieldTraversal {
+    /// The current GEP index.
+    gep_index_counter: u32,
+}
+
+impl<'ctx> FieldTraversal<'ctx> for GepFieldTraversal {
+    type Output<M> = GepField<M>;
+
+    fn add<M: Model<'ctx>>(&mut self, name: &'static str, model: M) -> Self::Output<M> {
+        let gep_index = self.gep_index_counter;
+        self.gep_index_counter += 1;
+        Self::Output { gep_index, name, model }
+    }
+}
+
+/// A traversal to collect the field types of a struct.
+///
+/// This is used to collect field types and construct the LLVM struct type with [`Context::struct_type`].
+struct TypeFieldTraversal<'ctx, 'a, G: CodeGenerator + ?Sized> {
+    generator: &'a G,
+    ctx: &'ctx Context,
+    /// The collected field types so far in exact order.
+    field_types: Vec<BasicTypeEnum<'ctx>>,
+}
+
+impl<'ctx, 'a, G: CodeGenerator + ?Sized> FieldTraversal<'ctx> for TypeFieldTraversal<'ctx, 'a, G> {
+    type Output<M> = (); // Checking types return nothing.
+
+    fn add<M: Model<'ctx>>(&mut self, _name: &'static str, model: M) -> Self::Output<M> {
+        let t = model.llvm_type(self.generator, self.ctx).as_basic_type_enum();
+        self.field_types.push(t);
+    }
+}
+
+/// A traversal to check the types of fields.
+struct CheckTypeFieldTraversal<'ctx, 'a, G: CodeGenerator + ?Sized> {
+    generator: &'a mut G,
+    ctx: &'ctx Context,
+    /// The current GEP index, so we can tell the index of the field we are checking
+    /// and report the GEP index.
+    gep_index_counter: u32,
+    /// The [`StructType`] to check.
+    scrutinee: StructType<'ctx>,
+    /// The list of collected errors so far.
+    errors: Vec<ModelError>,
+}
+
+impl<'ctx, 'a, G: CodeGenerator + ?Sized> FieldTraversal<'ctx>
+    for CheckTypeFieldTraversal<'ctx, 'a, G>
+{
+    type Output<M> = (); // Checking types return nothing.
+
+    fn add<M: Model<'ctx>>(&mut self, name: &'static str, model: M) -> Self::Output<M> {
+        let gep_index = self.gep_index_counter;
+        self.gep_index_counter += 1;
+
+        if let Some(t) = self.scrutinee.get_field_type_at_index(gep_index) {
+            if let Err(err) = model.check_type(self.generator, self.ctx, t) {
+                self.errors
+                    .push(err.under_context(format!("field #{gep_index} '{name}'").as_str()));
+            }
+        }
+        // Otherwise, it will be caught by Struct's `check_type`.
+    }
+}
+
+/// A trait for Rust structs identifying LLVM structures.
+///
+/// ### Example
+///
+/// Suppose you want to define this structure:
+/// ```c
+/// template <typename T>
+/// struct ContiguousNDArray {
+///     size_t ndims;
+///     size_t* shape;
+///     T* data;
+/// }
+/// ```
+///
+/// This is how it should be done:
+/// ```ignore
+/// pub struct ContiguousNDArrayFields<'ctx, F: FieldTraversal<'ctx>, Item: Model<'ctx>> {
+///     pub ndims: F::Out<Int<SizeT>>,
+///     pub shape: F::Out<Ptr<Int<SizeT>>>,
+///     pub data: F::Out<Ptr<Item>>,
+/// }
+///
+/// /// An ndarray without strides and non-opaque `data` field in NAC3.
+/// #[derive(Debug, Clone, Copy)]
+/// pub struct ContiguousNDArray<M> {
+///     /// [`Model`] of the items.
+///     pub item: M,
+/// }
+///
+/// impl<'ctx, Item: Model<'ctx>> StructKind<'ctx> for ContiguousNDArray<Item> {
+///     type Fields<F: FieldTraversal<'ctx>> = ContiguousNDArrayFields<'ctx, F, Item>;
+///
+///     fn traverse_fields<F: FieldTraversal<'ctx>>(&self, traversal: &mut F) -> Self::Fields<F> {
+///         // The order of `traversal.add*` is important
+///         Self::Fields {
+///             ndims: traversal.add_auto("ndims"),
+///             shape: traversal.add_auto("shape"),
+///             data: traversal.add("data", Ptr(self.item)),
+///         }
+///     }
+/// }
+/// ```
+///
+/// The [`FieldTraversal`] here is a mechanism to allow the fields of `ContiguousNDArrayFields` to be
+/// traversed to do useful work such as:
+///
+/// - To create the [`StructType`] of `ContiguousNDArray` by collecting [`BasicType`]s of the fields.
+/// - To enable the `.gep(ctx, |f| f.ndims).store(ctx, ...)` syntax.
+///
+/// Suppose now that you have defined `ContiguousNDArray` and you want to allocate a `ContiguousNDArray`
+/// with dtype `float64` in LLVM, this is how you do it:
+/// ```ignore
+/// type F64NDArray = Struct<ContiguousNDArray<Float<Float64>>>; // Type alias for leaner documentation
+/// let model: F64NDArray = Struct(ContigousNDArray { item: Float(Float64) });
+/// let ndarray: Instance<'ctx, Ptr<F64NDArray>> = model.alloca(generator, ctx);
+/// ```
+///
+/// ...and here is how you may manipulate/access `ndarray`:
+///
+/// (NOTE: some arguments have been omitted)
+///
+/// ```ignore
+/// // Get `&ndarray->data`
+/// ndarray.gep(|f| f.data); // type: Instance<'ctx, Ptr<Float<Float64>>>
+///
+/// // Get `ndarray->ndims`
+/// ndarray.get(|f| f.ndims); // type: Instance<'ctx, Int<SizeT>>
+///
+/// // Get `&ndarray->ndims`
+/// ndarray.gep(|f| f.ndims); // type: Instance<'ctx, Ptr<Int<SizeT>>>
+///
+/// // Get `ndarray->shape[0]`
+/// ndarray.get(|f| f.shape).get_index_const(0); // Instance<'ctx, Int<SizeT>>
+///
+/// // Get `&ndarray->shape[2]`
+/// ndarray.get(|f| f.shape).offset_const(2); // Instance<'ctx, Ptr<Int<SizeT>>>
+///
+/// // Do `ndarray->ndims = 3;`
+/// let num_3 = Int(SizeT).const_int(3);
+/// ndarray.set(|f| f.ndims, num_3);
+/// ```
+pub trait StructKind<'ctx>: fmt::Debug + Clone + Copy {
+    /// The associated fields of this struct.
+    type Fields<F: FieldTraversal<'ctx>>;
+
+    /// Traverse through all fields of this [`StructKind`].
+    ///
+    /// Only used internally in this module for implementing other components.
+    fn iter_fields<F: FieldTraversal<'ctx>>(&self, traversal: &mut F) -> Self::Fields<F>;
+
+    /// Get a convenience structure to get a struct field's GEP index through its corresponding Rust field.
+    ///
+    /// Only used internally in this module for implementing other components.
+    fn fields(&self) -> Self::Fields<GepFieldTraversal> {
+        self.iter_fields(&mut GepFieldTraversal { gep_index_counter: 0 })
+    }
+
+    /// Get the LLVM [`StructType`] of this [`StructKind`].
+    fn get_struct_type<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &'ctx Context,
+    ) -> StructType<'ctx> {
+        let mut traversal = TypeFieldTraversal { generator, ctx, field_types: Vec::new() };
+        self.iter_fields(&mut traversal);
+
+        ctx.struct_type(&traversal.field_types, false)
+    }
+}
+
+/// A model for LLVM struct.
+///
+/// `S` should be of a [`StructKind`].
+#[derive(Debug, Clone, Copy, Default)]
+pub struct Struct<S>(pub S);
+
+impl<'ctx, S: StructKind<'ctx>> Struct<S> {
+    /// Create a constant struct value from its fields.
+    ///
+    /// This function also validates `fields` and panic when there is something wrong.
+    pub fn const_struct<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        fields: &[BasicValueEnum<'ctx>],
+    ) -> Instance<'ctx, Self> {
+        // NOTE: There *could* have been a functor `F<M> = Instance<'ctx, M>` for `S::Fields<F>`
+        // to create a more user-friendly interface, but Rust's type system is not sophisticated enough
+        // and if you try doing that Rust would force you put lifetimes everywhere.
+        let val = ctx.const_struct(fields, false);
+        self.check_value(generator, ctx, val).unwrap()
+    }
+}
+
+impl<'ctx, S: StructKind<'ctx>> Model<'ctx> for Struct<S> {
+    type Value = StructValue<'ctx>;
+    type Type = StructType<'ctx>;
+
+    fn llvm_type<G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &G,
+        ctx: &'ctx Context,
+    ) -> Self::Type {
+        self.0.get_struct_type(generator, ctx)
+    }
+
+    fn check_type<T: BasicType<'ctx>, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        ty: T,
+    ) -> Result<(), ModelError> {
+        let ty = ty.as_basic_type_enum();
+        let Ok(ty) = StructType::try_from(ty) else {
+            return Err(ModelError(format!("Expecting StructType, but got {ty:?}")));
+        };
+
+        // Check each field individually.
+        let mut traversal = CheckTypeFieldTraversal {
+            generator,
+            ctx,
+            gep_index_counter: 0,
+            errors: Vec::new(),
+            scrutinee: ty,
+        };
+        self.0.iter_fields(&mut traversal);
+
+        // Check the number of fields.
+        let exp_num_fields = traversal.gep_index_counter;
+        let got_num_fields = u32::try_from(ty.get_field_types().len()).unwrap();
+        if exp_num_fields != got_num_fields {
+            return Err(ModelError(format!(
+                "Expecting StructType with {exp_num_fields} field(s), but got {got_num_fields}"
+            )));
+        }
+
+        if !traversal.errors.is_empty() {
+            // Currently, only the first error is reported.
+            return Err(traversal.errors[0].clone());
+        }
+
+        Ok(())
+    }
+}
+
+impl<'ctx, S: StructKind<'ctx>> Instance<'ctx, Struct<S>> {
+    /// Get a field with [`StructValue::get_field_at_index`].
+    pub fn get_field<G: CodeGenerator + ?Sized, M, GetField>(
+        &self,
+        generator: &mut G,
+        ctx: &'ctx Context,
+        get_field: GetField,
+    ) -> Instance<'ctx, M>
+    where
+        M: Model<'ctx>,
+        GetField: FnOnce(S::Fields<GepFieldTraversal>) -> GepField<M>,
+    {
+        let field = get_field(self.model.0.fields());
+        let val = self.value.get_field_at_index(field.gep_index).unwrap();
+        field.model.check_value(generator, ctx, val).unwrap()
+    }
+}
+
+impl<'ctx, S: StructKind<'ctx>> Instance<'ctx, Ptr<Struct<S>>> {
+    /// Get a pointer to a field with [`Builder::build_in_bounds_gep`].
+    pub fn gep<M, GetField>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        get_field: GetField,
+    ) -> Instance<'ctx, Ptr<M>>
+    where
+        M: Model<'ctx>,
+        GetField: FnOnce(S::Fields<GepFieldTraversal>) -> GepField<M>,
+    {
+        let field = get_field(self.model.0 .0.fields());
+        let llvm_i32 = ctx.ctx.i32_type();
+
+        let ptr = unsafe {
+            ctx.builder
+                .build_in_bounds_gep(
+                    self.value,
+                    &[llvm_i32.const_zero(), llvm_i32.const_int(u64::from(field.gep_index), false)],
+                    field.name,
+                )
+                .unwrap()
+        };
+
+        unsafe { Ptr(field.model).believe_value(ptr) }
+    }
+
+    /// Convenience function equivalent to `.gep(...).load(...)`.
+    pub fn get<M, GetField, G: CodeGenerator + ?Sized>(
+        &self,
+        generator: &mut G,
+        ctx: &CodeGenContext<'ctx, '_>,
+        get_field: GetField,
+    ) -> Instance<'ctx, M>
+    where
+        M: Model<'ctx>,
+        GetField: FnOnce(S::Fields<GepFieldTraversal>) -> GepField<M>,
+    {
+        self.gep(ctx, get_field).load(generator, ctx)
+    }
+
+    /// Convenience function equivalent to `.gep(...).store(...)`.
+    pub fn set<M, GetField>(
+        &self,
+        ctx: &CodeGenContext<'ctx, '_>,
+        get_field: GetField,
+        value: Instance<'ctx, M>,
+    ) where
+        M: Model<'ctx>,
+        GetField: FnOnce(S::Fields<GepFieldTraversal>) -> GepField<M>,
+    {
+        self.gep(ctx, get_field).store(ctx, value);
+    }
+}

nac3core/src/codegen/numpy.rs

@@ -12,6 +12,7 @@ use crate::{
             call_ndarray_calc_size,
         },
         llvm_intrinsics::{self, call_memcpy_generic},
+        macros::codegen_unreachable,
         stmt::{gen_for_callback_incrementing, gen_for_range_callback, gen_if_else_expr_callback},
         CodeGenContext, CodeGenerator,
     },
@@ -259,7 +260,7 @@ fn ndarray_zero_value<'ctx, G: CodeGenerator + ?Sized>(
     } else if ctx.unifier.unioned(elem_ty, ctx.primitives.str) {
         ctx.gen_string(generator, "").into()
     } else {
-        unreachable!()
+        codegen_unreachable!(ctx)
     }
 }
 
@@ -287,7 +288,7 @@ fn ndarray_one_value<'ctx, G: CodeGenerator + ?Sized>(
     } else if ctx.unifier.unioned(elem_ty, ctx.primitives.str) {
         ctx.gen_string(generator, "1").into()
     } else {
-        unreachable!()
+        codegen_unreachable!(ctx)
     }
 }
 
@@ -355,7 +356,7 @@ fn call_ndarray_empty_impl<'ctx, G: CodeGenerator + ?Sized>(
 
             create_ndarray_const_shape(generator, ctx, elem_ty, &[shape_int])
         }
-        _ => unreachable!(),
+        _ => codegen_unreachable!(ctx),
     }
 }
 
@@ -626,7 +627,7 @@ fn call_ndarray_full_impl<'ctx, G: CodeGenerator + ?Sized>(
         } else if fill_value.is_int_value() || fill_value.is_float_value() {
             fill_value
         } else {
-            unreachable!()
+            codegen_unreachable!(ctx)
         };
 
         Ok(value)
@@ -2020,7 +2021,7 @@ pub fn gen_ndarray_fill<'ctx>(
             } else if value_arg.is_int_value() || value_arg.is_float_value() {
                 value_arg
             } else {
-                unreachable!()
+                codegen_unreachable!(ctx)
             };
 
             Ok(value)
@@ -2129,7 +2130,8 @@ pub fn ndarray_transpose<'ctx, G: CodeGenerator + ?Sized>(
 
         Ok(out.as_base_value().into())
     } else {
-        unreachable!(
+        codegen_unreachable!(
+            ctx,
             "{FN_NAME}() not supported for '{}'",
             format!("'{}'", ctx.unifier.stringify(x1_ty))
         )
@@ -2371,7 +2373,7 @@ pub fn ndarray_reshape<'ctx, G: CodeGenerator + ?Sized>(
                 .into_int_value();
                 create_ndarray_const_shape(generator, ctx, elem_ty, &[shape_int])
             }
-            _ => unreachable!(),
+            _ => codegen_unreachable!(ctx),
         }
         .unwrap();
 
@@ -2415,7 +2417,8 @@ pub fn ndarray_reshape<'ctx, G: CodeGenerator + ?Sized>(
 
         Ok(out.as_base_value().into())
     } else {
-        unreachable!(
+        codegen_unreachable!(
+            ctx,
             "{FN_NAME}() not supported for '{}'",
             format!("'{}'", ctx.unifier.stringify(x1_ty))
         )
@@ -2483,7 +2486,7 @@ pub fn ndarray_dot<'ctx, G: CodeGenerator + ?Sized>(
                             .build_float_mul(e1, elem2.into_float_value(), "")
                             .unwrap()
                             .as_basic_value_enum(),
-                        _ => unreachable!(),
+                        _ => codegen_unreachable!(ctx),
                     };
                     let acc_val = ctx.builder.build_load(acc, "").unwrap();
                     let acc_val = match acc_val {
@@ -2497,7 +2500,7 @@ pub fn ndarray_dot<'ctx, G: CodeGenerator + ?Sized>(
                             .build_float_add(e1, product.into_float_value(), "")
                             .unwrap()
                             .as_basic_value_enum(),
-                        _ => unreachable!(),
+                        _ => codegen_unreachable!(ctx),
                     };
                     ctx.builder.build_store(acc, acc_val).unwrap();
 
@@ -2514,7 +2517,8 @@ pub fn ndarray_dot<'ctx, G: CodeGenerator + ?Sized>(
         (BasicValueEnum::FloatValue(e1), BasicValueEnum::FloatValue(e2)) => {
             Ok(ctx.builder.build_float_mul(e1, e2, "").unwrap().as_basic_value_enum())
         }
-        _ => unreachable!(
+        _ => codegen_unreachable!(
+            ctx,
             "{FN_NAME}() not supported for '{}'",
             format!("'{}'", ctx.unifier.stringify(x1_ty))
         ),

nac3core/src/codegen/stmt.rs

@@ -1,15 +1,13 @@
 use super::{
-    super::symbol_resolver::ValueEnum,
-    expr::destructure_range,
+    classes::{ArrayLikeIndexer, ArraySliceValue, ListValue, RangeValue},
+    expr::{destructure_range, gen_binop_expr},
+    gen_in_range_check,
     irrt::{handle_slice_indices, list_slice_assignment},
+    macros::codegen_unreachable,
     CodeGenContext, CodeGenerator,
 };
 use crate::{
-    codegen::{
-        classes::{ArrayLikeIndexer, ArraySliceValue, ListValue, RangeValue},
-        expr::gen_binop_expr,
-        gen_in_range_check,
-    },
+    symbol_resolver::ValueEnum,
     toplevel::{DefinitionId, TopLevelDef},
     typecheck::{
         magic_methods::Binop,
@@ -121,7 +119,7 @@ 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 +133,7 @@ pub fn gen_store_target<'ctx, G: CodeGenerator>(
             }
             .unwrap()
         }
-        _ => unreachable!(),
+        _ => codegen_unreachable!(ctx),
     }))
 }
 
@@ -176,6 +174,14 @@ 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 +199,12 @@ 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 +264,7 @@ 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
@@ -306,7 +312,9 @@ pub fn gen_setitem<'ctx, G: CodeGenerator>(
 
             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,
@@ -416,7 +424,9 @@ 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
@@ -458,7 +468,7 @@ pub fn gen_for<G: CodeGenerator>(
             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 +911,7 @@ 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 +941,7 @@ 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 +1089,7 @@ 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 +1212,11 @@ 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 +1324,7 @@ 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 +1401,7 @@ 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 +1673,23 @@ 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 +1700,6 @@ 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 +1768,30 @@ 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(());

nac3core/src/toplevel/composer.rs

@@ -23,7 +23,7 @@ impl Default for ComposerConfig {
     }
 }
 
-type DefAst = (Arc<RwLock<TopLevelDef>>, Option<Stmt<()>>);
+pub type DefAst = (Arc<RwLock<TopLevelDef>>, Option<Stmt<()>>);
 pub struct TopLevelComposer {
     // list of top level definitions, same as top level context
     pub definition_ast_list: Vec<DefAst>,
@@ -1822,7 +1822,12 @@ impl TopLevelComposer {
                         if *name != init_str_id {
                             unreachable!("must be init function here")
                         }
-                        let all_inited = Self::get_all_assigned_field(body.as_slice())?;
+
+                        let all_inited = Self::get_all_assigned_field(
+                            object_id.0,
+                            definition_ast_list,
+                            body.as_slice(),
+                        )?;
                         for (f, _, _) in fields {
                             if !all_inited.contains(f) {
                                 return Err(HashSet::from([

nac3core/src/toplevel/helper.rs

@@ -3,6 +3,7 @@ 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 ast::ExprKind;
 use nac3parser::ast::{Constant, Location};
 use strum::IntoEnumIterator;
 use strum_macros::EnumIter;
@@ -733,7 +734,16 @@ 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 +779,138 @@ 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(orelse.as_slice())?);
+                    result.extend(Self::get_all_assigned_field(
+                        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())?
-                        .intersection(&Self::get_all_assigned_field(orelse.as_slice())?)
-                        .copied()
-                        .collect::<HashSet<_>>();
+                    let inited_for_sure = Self::get_all_assigned_field(
+                        class_id,
+                        definition_ast_list,
+                        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())?
-                        .intersection(&Self::get_all_assigned_field(orelse.as_slice())?)
-                        .copied()
-                        .collect::<HashSet<_>>();
+                    let inited_for_sure = Self::get_all_assigned_field(
+                        class_id,
+                        definition_ast_list,
+                        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!()

nac3core/src/typecheck/magic_methods.rs

@@ -520,6 +520,23 @@ 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_inferencer/mod.rs

@@ -12,6 +12,7 @@ use super::{
         RecordField, RecordKey, Type, TypeEnum, TypeVar, Unifier, VarMap,
     },
 };
+use crate::toplevel::type_annotation::TypeAnnotation;
 use crate::{
     symbol_resolver::{SymbolResolver, SymbolValue},
     toplevel::{
@@ -102,6 +103,7 @@ pub struct Inferencer<'a> {
 }
 
 type InferenceError = HashSet<String>;
+type OverrideResult = Result<Option<ast::Expr<Option<Type>>>, InferenceError>;
 
 struct NaiveFolder();
 impl Fold<()> for NaiveFolder {
@@ -1672,6 +1674,86 @@ 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 +1767,20 @@ impl<'a> Inferencer<'a> {
             return Ok(spec_call_func);
         }
 
-        let func = Box::new(self.fold_expr(func)?);
-        let args = args.into_iter().map(|v| self.fold_expr(v)).collect::<Result<Vec<_>, _>>()?;
+        // Check for call to parent method
+        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))

nac3standalone/demo/demo.c

@@ -7,11 +7,11 @@
 #include <string.h>
 
 double dbl_nan(void) {
-  return NAN;
+    return NAN;
 }
 
 double dbl_inf(void) {
-  return INFINITY;
+    return INFINITY;
 }
 
 void output_bool(bool x) {
@@ -19,19 +19,19 @@ void output_bool(bool x) {
 }
 
 void output_int32(int32_t x) {
-    printf("%"PRId32"\n", x);
+    printf("%" PRId32 "\n", x);
 }
 
 void output_int64(int64_t x) {
-    printf("%"PRId64"\n", x);
+    printf("%" PRId64 "\n", x);
 }
 
 void output_uint32(uint32_t x) {
-    printf("%"PRIu32"\n", x);
+    printf("%" PRIu32 "\n", x);
 }
 
 void output_uint64(uint64_t x) {
-    printf("%"PRIu64"\n", x);
+    printf("%" PRIu64 "\n", x);
 }
 
 void output_float64(double x) {
@@ -52,7 +52,7 @@ void output_range(int32_t range[3]) {
 }
 
 void output_asciiart(int32_t x) {
-    static const char *chars = " .,-:;i+hHM$*#@    ";
+    static const char* chars = " .,-:;i+hHM$*#@    ";
     if (x < 0) {
         putchar('\n');
     } else {
@@ -61,12 +61,12 @@ void output_asciiart(int32_t x) {
 }
 
 struct cslice {
-    void *data;
+    void* data;
     size_t len;
 };
 
-void output_int32_list(struct cslice *slice) {
-    const int32_t *data = (int32_t *) slice->data;
+void output_int32_list(struct cslice* slice) {
+    const int32_t* data = (int32_t*)slice->data;
 
     putchar('[');
     for (size_t i = 0; i < slice->len; ++i) {
@@ -80,23 +80,23 @@ void output_int32_list(struct cslice *slice) {
     putchar('\n');
 }
 
-void output_str(struct cslice *slice) {
-    const char *data = (const char *) slice->data;
+void output_str(struct cslice* slice) {
+    const char* data = (const char*)slice->data;
 
     for (size_t i = 0; i < slice->len; ++i) {
         putchar(data[i]);
     }
 }
 
-void output_strln(struct cslice *slice) {
+void output_strln(struct cslice* slice) {
     output_str(slice);
     putchar('\n');
 }
 
-uint64_t dbg_stack_address(__attribute__((unused)) struct cslice *slice) {
+uint64_t dbg_stack_address(__attribute__((unused)) struct cslice* slice) {
     int i;
-    void *ptr = (void *) &i;
-    return (uintptr_t) ptr;
+    void* ptr = (void*)&i;
+    return (uintptr_t)ptr;
 }
 
 uint32_t __nac3_personality(uint32_t state, uint32_t exception_object, uint32_t context) {
@@ -119,11 +119,12 @@ struct Exception {
 
 uint32_t __nac3_raise(struct Exception* e) {
     printf("__nac3_raise called. Exception details:\n");
-    printf("          ID: %"PRIu32"\n", e->id);
-    printf("    Location: %*s:%"PRIu32":%"PRIu32"\n" , (int) e->file.len, (const char*) e->file.data, e->line, e->column);
-    printf("    Function: %*s\n" , (int) e->function.len, (const char*) e->function.data);
-    printf("     Message: \"%*s\"\n" , (int) e->message.len, (const char*) e->message.data);
-    printf("      Params: {0}=%"PRId64", {1}=%"PRId64", {2}=%"PRId64"\n", e->param[0], e->param[1], e->param[2]);
+    printf("          ID: %" PRIu32 "\n", e->id);
+    printf("    Location: %*s:%" PRIu32 ":%" PRIu32 "\n", (int)e->file.len, (const char*)e->file.data, e->line,
+           e->column);
+    printf("    Function: %*s\n", (int)e->function.len, (const char*)e->function.data);
+    printf("     Message: \"%*s\"\n", (int)e->message.len, (const char*)e->message.data);
+    printf("      Params: {0}=%" PRId64 ", {1}=%" PRId64 ", {2}=%" PRId64 "\n", e->param[0], e->param[1], e->param[2]);
     exit(101);
     __builtin_unreachable();
 }

nac3standalone/demo/src/assignment.py

@@ -9,6 +9,7 @@ def output_bool(x: bool):
 def example1():
     x, *ys, z = (1, 2, 3, 4, 5)
     output_int32(x)
+    output_int32(len(ys))
     output_int32(ys[0])
     output_int32(ys[1])
     output_int32(ys[2])
@@ -18,12 +19,14 @@ def example2():
     x, y, *zs = (1, 2, 3, 4, 5)
     output_int32(x)
     output_int32(y)
+    output_int32(len(zs))
     output_int32(zs[0])
     output_int32(zs[1])
     output_int32(zs[2])
 
 def example3():
     *xs, y, z = (1, 2, 3, 4, 5)
+    output_int32(len(xs))
     output_int32(xs[0])
     output_int32(xs[1])
     output_int32(xs[2])
@@ -31,6 +34,12 @@ def example3():
     output_int32(z)
 
 def example4():
+    *xs, y, z = (4, 5)
+    output_int32(len(xs))
+    output_int32(y)
+    output_int32(z)
+
+def example5():
     # Example from: https://docs.python.org/3/reference/simple_stmts.html#assignment-statements
     x = [0, 1]
     i = 0
@@ -44,7 +53,7 @@ class A:
     def __init__(self):
         self.value = 1000
 
-def example5():
+def example6():
     ws = [88, 7, 8]
     a = A()
     x, [y, *ys, a.value], ws[0], (ws[0],) = 1, (2, False, 4, 5), 99, (6,)
@@ -63,4 +72,5 @@ def run() -> int32:
     example3()
     example4()
     example5()
+    example6()
     return 0

nac3standalone/demo/src/inheritance.py

@@ -10,23 +10,58 @@ class A:
     def __init__(self, a: int32):
         self.a = a
     
-    def f1(self):
-        self.f2()
-    
-    def f2(self):
+    def output_all_fields(self):
         output_int32(self.a)
+    
+    def set_a(self, a: int32):
+        self.a = a
 
 class B(A):
     b: int32
 
     def __init__(self, b: int32):
-        self.a = b + 1
+        A.__init__(self, b + 1)
+        self.set_b(b)
+    
+    def output_parent_fields(self):
+        A.output_all_fields(self)
+
+    def output_all_fields(self):
+        A.output_all_fields(self)
+        output_int32(self.b)
+    
+    def set_b(self, b: int32):
         self.b = b
 
+class C(B):
+    c: int32
+
+    def __init__(self, c: int32):
+        B.__init__(self, c + 1)
+        self.c = c
+    
+    def output_parent_fields(self):
+        B.output_all_fields(self)
+
+    def output_all_fields(self):
+        B.output_all_fields(self)
+        output_int32(self.c)
+    
+    def set_c(self, c: int32):
+        self.c = c
 
 def run() -> int32:
-    aaa = A(5)
-    bbb = B(2)
-    aaa.f1()
-    bbb.f1()
+    ccc = C(10)
+    ccc.output_all_fields()
+    ccc.set_a(1)
+    ccc.set_b(2)
+    ccc.set_c(3)
+    ccc.output_all_fields()
+
+    bbb = B(10)
+    bbb.set_a(9)
+    bbb.set_b(8)
+    bbb.output_all_fields()
+    ccc.output_all_fields()
+
     return 0

nac3standalone/src/basic_symbol_resolver.rs

@@ -15,7 +15,6 @@ use std::{collections::HashMap, sync::Arc};
 pub struct ResolverInternal {
     pub id_to_type: Mutex<HashMap<StrRef, Type>>,
     pub id_to_def: Mutex<HashMap<StrRef, DefinitionId>>,
-    pub class_names: Mutex<HashMap<StrRef, Type>>,
     pub module_globals: Mutex<HashMap<StrRef, SymbolValue>>,
     pub str_store: Mutex<HashMap<String, i32>>,
 }

nac3standalone/src/main.rs

@@ -306,7 +306,6 @@ fn main() {
     let internal_resolver: Arc<ResolverInternal> = ResolverInternal {
         id_to_type: builtins_ty.into(),
         id_to_def: builtins_def.into(),
-        class_names: Mutex::default(),
         module_globals: Mutex::default(),
         str_store: Mutex::default(),
     }
@@ -314,6 +313,15 @@ fn main() {
     let resolver =
         Arc::new(Resolver(internal_resolver.clone())) as Arc<dyn SymbolResolver + Send + Sync>;
 
+    let context = inkwell::context::Context::create();
+
+    // Process IRRT
+    let irrt = load_irrt(&context, resolver.as_ref());
+    if emit_llvm {
+        irrt.write_bitcode_to_path(Path::new("irrt.bc"));
+    }
+
+    // Process the Python script
     let parser_result = parser::parse_program(&program, file_name.into()).unwrap();
 
     for stmt in parser_result {
@@ -418,8 +426,8 @@ fn main() {
     registry.add_task(task);
     registry.wait_tasks_complete(handles);
 
+    // Link all modules together into `main`
     let buffers = membuffers.lock();
-    let context = inkwell::context::Context::create();
     let main = context
         .create_module_from_ir(MemoryBuffer::create_from_memory_range(&buffers[0], "main"))
         .unwrap();
@@ -439,12 +447,9 @@ fn main() {
         main.link_in_module(other).unwrap();
     }
 
-    let irrt = load_irrt(&context);
-    if emit_llvm {
-        irrt.write_bitcode_to_path(Path::new("irrt.bc"));
-    }
     main.link_in_module(irrt).unwrap();
 
+    // Private all functions except "run"
     let mut function_iter = main.get_first_function();
     while let Some(func) = function_iter {
         if func.count_basic_blocks() > 0 && func.get_name().to_str().unwrap() != "run" {
@@ -453,6 +458,7 @@ fn main() {
         function_iter = func.get_next_function();
     }
 
+    // Optimize `main`
     let target_machine = llvm_options
         .target
         .create_target_machine(llvm_options.opt_level)
@@ -466,6 +472,7 @@ fn main() {
         panic!("Failed to run optimization for module `main`: {}", err.to_string());
     }
 
+    // Write output
     target_machine
         .write_to_file(&main, FileType::Object, Path::new("module.o"))
         .expect("couldn't write module to file");