Nikita Popov 158d72d728
[Clang] Set writable and dead_on_unwind attributes on sret arguments (#77116)
Set the writable and dead_on_unwind attributes for sret arguments. These
indicate that the argument points to writable memory (and it's legal to
introduce spurious writes to it on entry to the function) and that the
argument memory will not be used if the call unwinds.

This enables additional MemCpyOpt/DSE/LICM optimizations.
2024-01-11 09:46:54 +01:00

29 lines
1.7 KiB
C

// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py
// RUN: %clang_cc1 -emit-llvm %s -o - -ffreestanding -target-feature +avx512vl -triple=x86_64-pc-win32 | FileCheck %s --check-prefix=Win
// RUN: %clang_cc1 -emit-llvm %s -o - -ffreestanding -target-feature +avx512vl -triple=x86_64-pc-linux-gnu | FileCheck %s --check-prefix=Lin
#include <immintrin.h>
typedef struct {
__m512d r1[4];
__m512 r2[4];
} __sVector;
__sVector A;
__sVector __regcall foo(int a) {
return A;
}
double __regcall bar(__sVector a) {
return a.r1[0][4];
}
// FIXME: Do we need to change for Windows?
// Win: define dso_local x86_regcallcc void @__regcall3__foo(ptr dead_on_unwind noalias writable sret(%struct.__sVector) align 64 %agg.result, i32 noundef %a) #0
// Win: define dso_local x86_regcallcc double @__regcall3__bar(ptr noundef %a) #0
// Win: attributes #0 = { noinline nounwind optnone "min-legal-vector-width"="0" "no-builtins" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-features"="+avx,+avx2,+avx512f,+avx512vl,+crc32,+cx8,+evex512,+f16c,+fma,+mmx,+popcnt,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave" }
// Lin: define dso_local x86_regcallcc %struct.__sVector @__regcall3__foo(i32 noundef %a) #0
// Lin: define dso_local x86_regcallcc double @__regcall3__bar([4 x <8 x double>] %a.coerce0, [4 x <16 x float>] %a.coerce1) #0
// Lin: attributes #0 = { noinline nounwind optnone "min-legal-vector-width"="512" "no-builtins" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-features"="+avx,+avx2,+avx512f,+avx512vl,+crc32,+cx8,+evex512,+f16c,+fma,+mmx,+popcnt,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave" }