mirrors/Odin
1
0
Fork 0
mirror of https://github.com/odin-lang/Odin.git synced 2026-08-24 05:51:34 +00:00
Code Issues Packages Projects Releases Wiki Activity

arm32: pass homogeneous vector aggregates in the VFP registers

Browse Source 
arm32: coerce narrow bare vectors, and return wide ones through a hidden pointer
This commit is contained in:
kalsprite
2026-08-14 18:42:23 -07:00
parent ee033f7ee8
commit eb72d8ffbe
1 changed files with 32 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
src/llvm_abi.cpp
View File

@@ -2111,6 +2111,20 @@ namespace lbAbiArm32 {
}
gb_internal lbArgType non_struct(LLVMContextRef c, LLVMTypeRef type, bool is_return, Type *source_type) {
// A bare vector narrower than a word has no register of its own to sit in, clang coerces
// it to `i32` as an argument whatever its element is. The return keeps the vector
// type, same as x86, except: a half vector is not a legal type at this microarchitecture
// (`arm1176jzf-s` has VFP2 but no fp16), so clang coerces that one in both directions.
//
// <4 x i8> <2 x i16> <2 x half> as an argument -> i32
// <4 x i8> <2 x i16> as a return -> unchanged
// <2 x half> as a return -> i32
if (LLVMGetTypeKind(type) == LLVMVectorTypeKind && lb_sizeof(type) == 4) {
bool is_half = LLVMGetTypeKind(LLVMGetElementType(type)) == LLVMHalfTypeKind;
if (!is_return || is_half) {
return lb_arg_type_direct(type, LLVMIntTypeInContext(c, 32), nullptr, nullptr);
}
}
LLVMAttributeRef attr = lb_integer_extension_attribute(c, type, source_type);
return lb_arg_type_direct(type, nullptr, nullptr, attr);
}
@@ -2147,6 +2161,17 @@ namespace lbAbiArm32 {
case LLVMFloatTypeKind:
case LLVMDoubleTypeKind:
break;
case LLVMVectorTypeKind:
// AAPCS32's short vectors are the 64-bit and 128-bit ones. An aggregate of up to
// four of them is a Homogeneous Vector Aggregate, which rides in the VFP registers
// exactly as an HFA does. Any other width is not a short vector and does not qualify.
{
i64 vec_size = lb_sizeof(base_type);
if (vec_size != 8 && vec_size != 16) {
return false;
}
}
break;
default:
return false;
}
@@ -2190,6 +2215,13 @@ namespace lbAbiArm32 {
gb_internal lbArgType compute_return_type(LLVMContextRef c, LLVMTypeRef return_type, bool return_is_defined, ProcCallingConvention calling_convention, Type *return_source) {
if (!return_is_defined) {
return lb_arg_type_direct(LLVMVoidTypeInContext(c));
} else if (LLVMGetTypeKind(return_type) == LLVMVectorTypeKind && lb_sizeof(return_type) > 16) {
// A bare vector wider than a short vector has no register file to come back in. It
// is returned through a hidden pointer. `is_register` answers true for every vector,
// without this the caller returns it directly while the C callee stores
// through an `sret` pointer that was never passed (segfault)
LLVMAttributeRef attr = lb_create_enum_attribute_with_type(c, "sret", return_type);
return lb_arg_type_indirect(return_type, attr);
} else if (!is_register(return_type, true)) {
if (calling_convention == ProcCC_CDecl && selected_subtarget == Subtarget_Playdate) {
return lb_arg_type_direct(return_type);