core/ndstrides: add ArrayWriter & make_shape_writer

nac3core/src/codegen/mod.rs

@@ -47,6 +47,7 @@ pub mod model;
 pub mod numpy;
 pub mod stmt;
 pub mod structure;
+pub mod util;
 
 #[cfg(test)]
 mod test;

nac3core/src/codegen/model/ptr.rs

@@ -75,6 +75,7 @@ impl<Element: Model> PtrModel<Element> {
 
 impl<'ctx, Element: Model> Ptr<'ctx, Element> {
     /// Offset the pointer by [`inkwell::builder::Builder::build_in_bounds_gep`].
+    #[must_use]
     pub fn offset(
         &self,
         tyctx: TypeContext<'ctx>,

nac3core/src/codegen/stmt.rs

@@ -508,8 +508,12 @@ where
     I: Clone,
     InitFn: FnOnce(&mut G, &mut CodeGenContext<'ctx, 'a>) -> Result<I, String>,
     CondFn: FnOnce(&mut G, &mut CodeGenContext<'ctx, 'a>, I) -> Result<IntValue<'ctx>, String>,
-    BodyFn:
+    BodyFn: FnOnce(
-        FnOnce(&mut G, &mut CodeGenContext<'ctx, 'a>, BreakContinueHooks, I) -> Result<(), String>,
+        &mut G,
+        &mut CodeGenContext<'ctx, 'a>,
+        BreakContinueHooks<'ctx>,
+        I,
+    ) -> Result<(), String>,
     UpdateFn: FnOnce(&mut G, &mut CodeGenContext<'ctx, 'a>, I) -> Result<(), String>,
 {
     let label = label.unwrap_or("for");
@@ -589,7 +593,7 @@ where
     BodyFn: FnOnce(
         &mut G,
         &mut CodeGenContext<'ctx, 'a>,
-        BreakContinueHooks,
+        BreakContinueHooks<'ctx>,
         IntValue<'ctx>,
     ) -> Result<(), String>,
 {

nac3core/src/codegen/util/array_writer.rs

@@ -0,0 +1,17 @@
+use crate::codegen::{model::*, CodeGenContext, CodeGenerator};
+
+/// A closure containing details on how to write to/initialize an array.
+#[allow(clippy::type_complexity)]
+pub struct ArrayWriter<'ctx, G: CodeGenerator + ?Sized, Len: IntKind, Item: Model> {
+    /// Number of items to write
+    pub len: Int<'ctx, Len>,
+    /// Implementation to write to an array given its base pointer.
+    pub write: Box<
+        dyn Fn(
+                &mut G,
+                &mut CodeGenContext<'ctx, '_>,
+                Ptr<'ctx, Item>, // Base pointer
+            ) -> Result<(), String>
+            + 'ctx,
+    >,
+}

nac3core/src/codegen/util/control.rs

@@ -0,0 +1,42 @@
+use crate::codegen::{
+    model::*,
+    stmt::{gen_for_callback_incrementing, BreakContinueHooks},
+    CodeGenContext, CodeGenerator,
+};
+
+// TODO: Document
+// TODO: Rename function
+/// Only allows positive steps
+pub fn gen_model_for<'ctx, 'a, G, F, I>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, 'a>,
+    start: Int<'ctx, I>,
+    stop: Int<'ctx, I>,
+    step: Int<'ctx, I>,
+    body: F,
+) -> Result<(), String>
+where
+    G: CodeGenerator + ?Sized,
+    F: FnOnce(
+        &mut G,
+        &mut CodeGenContext<'ctx, 'a>,
+        BreakContinueHooks<'ctx>,
+        Int<'ctx, I>,
+    ) -> Result<(), String>,
+    I: IntKind,
+{
+    let int_model = IntModel(I::default());
+
+    gen_for_callback_incrementing(
+        generator,
+        ctx,
+        None,
+        start.value,
+        (stop.value, false),
+        |g, ctx, hooks, i| {
+            let i = int_model.believe_value(i);
+            body(g, ctx, hooks, i)
+        },
+        step.value,
+    )
+}

nac3core/src/codegen/util/mod.rs

@@ -0,0 +1,3 @@
+pub mod array_writer;
+pub mod control;
+pub mod shape;

nac3core/src/codegen/util/shape.rs

@@ -0,0 +1,127 @@
+use inkwell::values::BasicValueEnum;
+
+use crate::{
+    codegen::{
+        classes::{ListValue, UntypedArrayLikeAccessor},
+        model::*,
+        CodeGenContext, CodeGenerator,
+    },
+    typecheck::typedef::{Type, TypeEnum},
+};
+
+use super::{array_writer::ArrayWriter, control::gen_model_for};
+
+// TODO: Generalize to complex iterables under a common interface
+/// Create an [`ArrayWriter`] from a NumPy-like `shape` argument input.
+/// * `shape` - The `shape` parameter.
+/// * `shape_ty` - The element type of the `NDArray`.
+///
+/// The `shape` argument type may only be one of the following:
+///   1. A list of `int32`;   e.g., `np.empty([600, 800, 3])`
+///   2. A tuple of `int32`;  e.g., `np.empty((600, 800, 3))`
+///   3. A scalar `int32`;     e.g., `np.empty(3)`, this is functionally equivalent to `np.empty([3])`
+///
+/// The `int32` values will be sign-extended to `SizeT`
+pub fn make_shape_writer<'ctx, G>(
+    generator: &mut G,
+    ctx: &mut CodeGenContext<'ctx, '_>,
+    shape: BasicValueEnum<'ctx>,
+    shape_ty: Type,
+) -> ArrayWriter<'ctx, G, SizeT, IntModel<SizeT>>
+where
+    G: CodeGenerator + ?Sized,
+{
+    let tyctx = generator.type_context(ctx.ctx);
+    let sizet_model = IntModel(SizeT);
+
+    match &*ctx.unifier.get_ty(shape_ty) {
+        TypeEnum::TObj { obj_id, .. }
+            if *obj_id == ctx.primitives.list.obj_id(&ctx.unifier).unwrap() =>
+        {
+            // 1. A list of `int32`;   e.g., `np.empty([600, 800, 3])`
+
+            // TODO: Remove ListValue with Model
+
+            let shape = ListValue::from_ptr_val(shape.into_pointer_value(), tyctx.size_type, None);
+            let len =
+                sizet_model.check_value(tyctx, ctx.ctx, shape.load_size(ctx, Some("len"))).unwrap();
+
+            ArrayWriter {
+                len,
+                write: Box::new(move |generator, ctx, dst_array| {
+                    gen_model_for(
+                        generator,
+                        ctx,
+                        sizet_model.constant(tyctx, ctx.ctx, 0),
+                        len,
+                        sizet_model.constant(tyctx, ctx.ctx, 1),
+                        |generator, ctx, _hooks, i| {
+                            let dim =
+                                shape.data().get(ctx, generator, &i.value, None).into_int_value();
+                            let dim = sizet_model.s_extend_or_bit_cast(tyctx, ctx, dim, "");
+
+                            dst_array.offset(tyctx, ctx, i.value, "pdim").store(ctx, dim);
+                            Ok(())
+                        },
+                    )
+                }),
+            }
+        }
+        TypeEnum::TTuple { ty: tuple_types } => {
+            // 2. A tuple of ints; e.g., `np.empty((600, 800, 3))`
+
+            let ndims = tuple_types.len();
+
+            // A tuple has to be a StructValue
+            // Read [`codegen::expr::gen_expr`] to see how `nac3core` translates a Python tuple into LLVM.
+            let shape = shape.into_struct_value();
+
+            ArrayWriter {
+                len: sizet_model.constant(tyctx, ctx.ctx, ndims as u64),
+                write: Box::new(move |_generator, ctx, dst_array| {
+                    for axis in 0..ndims {
+                        let dim = ctx
+                            .builder
+                            .build_extract_value(shape, axis as u32, format!("dim{axis}").as_str())
+                            .unwrap()
+                            .into_int_value();
+                        let dim = sizet_model.s_extend_or_bit_cast(tyctx, ctx, dim, "");
+
+                        dst_array
+                            .offset(
+                                tyctx,
+                                ctx,
+                                sizet_model.constant(tyctx, ctx.ctx, axis as u64).value,
+                                "pdim",
+                            )
+                            .store(ctx, dim);
+                    }
+                    Ok(())
+                }),
+            }
+        }
+        TypeEnum::TObj { obj_id, .. }
+            if *obj_id == ctx.primitives.int32.obj_id(&ctx.unifier).unwrap() =>
+        {
+            // 3. A scalar int; e.g., `np.empty(3)`, this is functionally equivalent to `np.empty([3])`
+
+            // The value has to be an integer
+            let shape_int = shape.into_int_value();
+
+            ArrayWriter {
+                len: sizet_model.constant(tyctx, ctx.ctx, 1),
+                write: Box::new(move |_generator, ctx, dst_array| {
+                    let dim = sizet_model.s_extend_or_bit_cast(tyctx, ctx, shape_int, "");
+
+                    // Set shape[0] = shape_int
+                    dst_array
+                        .offset(tyctx, ctx, sizet_model.constant(tyctx, ctx.ctx, 0).value, "pdim")
+                        .store(ctx, dim);
+
+                    Ok(())
+                }),
+            }
+        }
+        _ => panic!("encountered shape type"),
+    }
+}