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cg_llvm: simplify llvm.masked.gather/scatter naming with opaque pointers
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With opaque pointers, there's no longer a need to generate a chain
of pointer types in the intrinsic name when arguments are pointers to
pointers.
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@erikdesjardins
erikdesjardins committed Jul 29, 2023
1 parent cf7788d commit 5580012
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Showing 3 changed files with 51 additions and 109 deletions.
152 changes: 47 additions & 105 deletions compiler/rustc_codegen_llvm/src/intrinsic.rs
View file
Expand Up @@ -1307,49 +1307,34 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
// FIXME: use:
// https://github.com/llvm-mirror/llvm/blob/master/include/llvm/IR/Function.h#L182
// https://github.com/llvm-mirror/llvm/blob/master/include/llvm/IR/Intrinsics.h#L81
fn llvm_vector_str(
elem_ty: Ty<'_>,
vec_len: u64,
no_pointers: usize,
bx: &Builder<'_, '_, '_>,
) -> String {
let p0s: String = "p0".repeat(no_pointers);
fn llvm_vector_str(bx: &Builder<'_, '_, '_>, elem_ty: Ty<'_>, vec_len: u64) -> String {
match *elem_ty.kind() {
ty::Int(v) => format!(
"v{}{}i{}",
"v{}i{}",
vec_len,
p0s,
// Normalize to prevent crash if v: IntTy::Isize
v.normalize(bx.target_spec().pointer_width).bit_width().unwrap()
),
ty::Uint(v) => format!(
"v{}{}i{}",
"v{}i{}",
vec_len,
p0s,
// Normalize to prevent crash if v: UIntTy::Usize
v.normalize(bx.target_spec().pointer_width).bit_width().unwrap()
),
ty::Float(v) => format!("v{}{}f{}", vec_len, p0s, v.bit_width()),
ty::Float(v) => format!("v{}f{}", vec_len, v.bit_width()),
ty::RawPtr(_) => format!("v{}p0", vec_len),
_ => unreachable!(),
}
}

fn llvm_vector_ty<'ll>(
cx: &CodegenCx<'ll, '_>,
elem_ty: Ty<'_>,
vec_len: u64,
no_pointers: usize,
) -> &'ll Type {
// FIXME: use cx.layout_of(ty).llvm_type() ?
let mut elem_ty = match *elem_ty.kind() {
fn llvm_vector_ty<'ll>(cx: &CodegenCx<'ll, '_>, elem_ty: Ty<'_>, vec_len: u64) -> &'ll Type {
let elem_ty = match *elem_ty.kind() {
ty::Int(v) => cx.type_int_from_ty(v),
ty::Uint(v) => cx.type_uint_from_ty(v),
ty::Float(v) => cx.type_float_from_ty(v),
ty::RawPtr(_) => cx.type_ptr(),
_ => unreachable!(),
};
if no_pointers > 0 {
elem_ty = cx.type_ptr();
}
cx.type_vector(elem_ty, vec_len)
}

Expand Down Expand Up @@ -1404,47 +1389,26 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
InvalidMonomorphization::ExpectedReturnType { span, name, in_ty, ret_ty }
);

// This counts how many pointers
fn ptr_count(t: Ty<'_>) -> usize {
match t.kind() {
ty::RawPtr(p) => 1 + ptr_count(p.ty),
_ => 0,
}
}

// Non-ptr type
fn non_ptr(t: Ty<'_>) -> Ty<'_> {
match t.kind() {
ty::RawPtr(p) => non_ptr(p.ty),
_ => t,
}
}

// The second argument must be a simd vector with an element type that's a pointer
// to the element type of the first argument
let (_, element_ty0) = arg_tys[0].simd_size_and_type(bx.tcx());
let (_, element_ty1) = arg_tys[1].simd_size_and_type(bx.tcx());
let (pointer_count, underlying_ty) = match element_ty1.kind() {
ty::RawPtr(p) if p.ty == in_elem => (ptr_count(element_ty1), non_ptr(element_ty1)),
_ => {
require!(
false,
InvalidMonomorphization::ExpectedElementType {
span,
name,
expected_element: element_ty1,
second_arg: arg_tys[1],
in_elem,
in_ty,
mutability: ExpectedPointerMutability::Not,
}
);
unreachable!();

require!(
matches!(
element_ty1.kind(),
ty::RawPtr(p) if p.ty == in_elem && p.ty.kind() == element_ty0.kind()
),
InvalidMonomorphization::ExpectedElementType {
span,
name,
expected_element: element_ty1,
second_arg: arg_tys[1],
in_elem,
in_ty,
mutability: ExpectedPointerMutability::Not,
}
};
assert!(pointer_count > 0);
assert_eq!(pointer_count - 1, ptr_count(element_ty0));
assert_eq!(underlying_ty, non_ptr(element_ty0));
);

// The element type of the third argument must be a signed integer type of any width:
let (_, element_ty2) = arg_tys[2].simd_size_and_type(bx.tcx());
Expand Down Expand Up @@ -1475,12 +1439,12 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
};

// Type of the vector of pointers:
let llvm_pointer_vec_ty = llvm_vector_ty(bx, underlying_ty, in_len, pointer_count);
let llvm_pointer_vec_str = llvm_vector_str(underlying_ty, in_len, pointer_count, bx);
let llvm_pointer_vec_ty = llvm_vector_ty(bx, element_ty1, in_len);
let llvm_pointer_vec_str = llvm_vector_str(bx, element_ty1, in_len);

// Type of the vector of elements:
let llvm_elem_vec_ty = llvm_vector_ty(bx, underlying_ty, in_len, pointer_count - 1);
let llvm_elem_vec_str = llvm_vector_str(underlying_ty, in_len, pointer_count - 1, bx);
let llvm_elem_vec_ty = llvm_vector_ty(bx, element_ty0, in_len);
let llvm_elem_vec_str = llvm_vector_str(bx, element_ty0, in_len);

let llvm_intrinsic =
format!("llvm.masked.gather.{}.{}", llvm_elem_vec_str, llvm_pointer_vec_str);
Expand Down Expand Up @@ -1544,50 +1508,28 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
}
);

// This counts how many pointers
fn ptr_count(t: Ty<'_>) -> usize {
match t.kind() {
ty::RawPtr(p) => 1 + ptr_count(p.ty),
_ => 0,
}
}

// Non-ptr type
fn non_ptr(t: Ty<'_>) -> Ty<'_> {
match t.kind() {
ty::RawPtr(p) => non_ptr(p.ty),
_ => t,
}
}

// The second argument must be a simd vector with an element type that's a pointer
// to the element type of the first argument
let (_, element_ty0) = arg_tys[0].simd_size_and_type(bx.tcx());
let (_, element_ty1) = arg_tys[1].simd_size_and_type(bx.tcx());
let (_, element_ty2) = arg_tys[2].simd_size_and_type(bx.tcx());
let (pointer_count, underlying_ty) = match element_ty1.kind() {
ty::RawPtr(p) if p.ty == in_elem && p.mutbl.is_mut() => {
(ptr_count(element_ty1), non_ptr(element_ty1))
}
_ => {
require!(
false,
InvalidMonomorphization::ExpectedElementType {
span,
name,
expected_element: element_ty1,
second_arg: arg_tys[1],
in_elem,
in_ty,
mutability: ExpectedPointerMutability::Mut,
}
);
unreachable!();

require!(
matches!(
element_ty1.kind(),
ty::RawPtr(p)
if p.ty == in_elem && p.mutbl.is_mut() && p.ty.kind() == element_ty0.kind()
),
InvalidMonomorphization::ExpectedElementType {
span,
name,
expected_element: element_ty1,
second_arg: arg_tys[1],
in_elem,
in_ty,
mutability: ExpectedPointerMutability::Mut,
}
};
assert!(pointer_count > 0);
assert_eq!(pointer_count - 1, ptr_count(element_ty0));
assert_eq!(underlying_ty, non_ptr(element_ty0));
);

// The element type of the third argument must be a signed integer type of any width:
match element_ty2.kind() {
Expand Down Expand Up @@ -1619,12 +1561,12 @@ fn generic_simd_intrinsic<'ll, 'tcx>(
let ret_t = bx.type_void();

// Type of the vector of pointers:
let llvm_pointer_vec_ty = llvm_vector_ty(bx, underlying_ty, in_len, pointer_count);
let llvm_pointer_vec_str = llvm_vector_str(underlying_ty, in_len, pointer_count, bx);
let llvm_pointer_vec_ty = llvm_vector_ty(bx, element_ty1, in_len);
let llvm_pointer_vec_str = llvm_vector_str(bx, element_ty1, in_len);

// Type of the vector of elements:
let llvm_elem_vec_ty = llvm_vector_ty(bx, underlying_ty, in_len, pointer_count - 1);
let llvm_elem_vec_str = llvm_vector_str(underlying_ty, in_len, pointer_count - 1, bx);
let llvm_elem_vec_ty = llvm_vector_ty(bx, element_ty0, in_len);
let llvm_elem_vec_str = llvm_vector_str(bx, element_ty0, in_len);

let llvm_intrinsic =
format!("llvm.masked.scatter.{}.{}", llvm_elem_vec_str, llvm_pointer_vec_str);
Expand Down
4 changes: 2 additions & 2 deletions tests/codegen/simd-intrinsic/simd-intrinsic-generic-gather.rs
View file
Expand Up @@ -23,14 +23,14 @@ extern "platform-intrinsic" {
#[no_mangle]
pub unsafe fn gather_f32x2(pointers: Vec2<*const f32>, mask: Vec2<i32>,
values: Vec2<f32>) -> Vec2<f32> {
// CHECK: call <2 x float> @llvm.masked.gather.v2f32.{{.+}}(<2 x ptr> {{.*}}, i32 {{.*}}, <2 x i1> {{.*}}, <2 x float> {{.*}})
// CHECK: call <2 x float> @llvm.masked.gather.v2f32.v2p0(<2 x ptr> {{.*}}, i32 {{.*}}, <2 x i1> {{.*}}, <2 x float> {{.*}})
simd_gather(values, pointers, mask)
}

// CHECK-LABEL: @gather_pf32x2
#[no_mangle]
pub unsafe fn gather_pf32x2(pointers: Vec2<*const *const f32>, mask: Vec2<i32>,
values: Vec2<*const f32>) -> Vec2<*const f32> {
// CHECK: call <2 x ptr> @llvm.masked.gather.{{.+}}(<2 x ptr> {{.*}}, i32 {{.*}}, <2 x i1> {{.*}}, <2 x ptr> {{.*}})
// CHECK: call <2 x ptr> @llvm.masked.gather.v2p0.v2p0(<2 x ptr> {{.*}}, i32 {{.*}}, <2 x i1> {{.*}}, <2 x ptr> {{.*}})
simd_gather(values, pointers, mask)
}
4 changes: 2 additions & 2 deletions tests/codegen/simd-intrinsic/simd-intrinsic-generic-scatter.rs
View file
Expand Up @@ -23,7 +23,7 @@ extern "platform-intrinsic" {
#[no_mangle]
pub unsafe fn scatter_f32x2(pointers: Vec2<*mut f32>, mask: Vec2<i32>,
values: Vec2<f32>) {
// CHECK: call void @llvm.masked.scatter.v2f32.v2p0{{.*}}(<2 x float> {{.*}}, <2 x ptr> {{.*}}, i32 {{.*}}, <2 x i1> {{.*}})
// CHECK: call void @llvm.masked.scatter.v2f32.v2p0(<2 x float> {{.*}}, <2 x ptr> {{.*}}, i32 {{.*}}, <2 x i1> {{.*}})
simd_scatter(values, pointers, mask)
}

Expand All @@ -32,6 +32,6 @@ pub unsafe fn scatter_f32x2(pointers: Vec2<*mut f32>, mask: Vec2<i32>,
#[no_mangle]
pub unsafe fn scatter_pf32x2(pointers: Vec2<*mut *const f32>, mask: Vec2<i32>,
values: Vec2<*const f32>) {
// CHECK: call void @llvm.masked.scatter.v2p0{{.*}}.v2p0{{.*}}(<2 x ptr> {{.*}}, <2 x ptr> {{.*}}, i32 {{.*}}, <2 x i1> {{.*}})
// CHECK: call void @llvm.masked.scatter.v2p0.v2p0(<2 x ptr> {{.*}}, <2 x ptr> {{.*}}, i32 {{.*}}, <2 x i1> {{.*}})
simd_scatter(values, pointers, mask)
}

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