mirrors/llvm-project
0
0
Fork 0
mirror of https://github.com/llvm/llvm-project.git synced 2025-04-25 23:56:05 +00:00
Code Issues Projects Releases Wiki Activity

[X86][CodeGen] Fix crash when commute operands of Instruction for code size (#79245)

Browse Source 
Reported in 134fcc62786d31ab73439201dce2d73808d1785a

Incorrect opcode is used  b/c there is a `[[fallthrough]]` at line 2386.
This commit is contained in:
Shengchen Kan 2024-01-24 17:10:28 +08:00 committed by GitHub
parent b0763a1ae9
commit 33ecef9812
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 23 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
llvm/lib/Target/X86/X86InstrInfo.cpp
View File

@ -2326,33 +2326,26 @@ MachineInstr *X86InstrInfo::commuteInstructionImpl(MachineInstr &MI, bool NewMI,
case X86::VBLENDPSrri:
// If we're optimizing for size, try to use MOVSD/MOVSS.
if (MI.getParent()->getParent()->getFunction().hasOptSize()) {
unsigned Mask;
switch (Opc) {
default:
llvm_unreachable("Unreachable!");
case X86::BLENDPDrri:
Opc = X86::MOVSDrr;
Mask = 0x03;
break;
case X86::BLENDPSrri:
Opc = X86::MOVSSrr;
Mask = 0x0F;
break;
case X86::VBLENDPDrri:
Opc = X86::VMOVSDrr;
Mask = 0x03;
break;
case X86::VBLENDPSrri:
Opc = X86::VMOVSSrr;
Mask = 0x0F;
break;
}
unsigned Mask = (Opc == X86::BLENDPDrri || Opc == X86::VBLENDPDrri) ? 0x03: 0x0F;
if ((MI.getOperand(3).getImm() ^ Mask) == 1) {
#define FROM_TO(FROM, TO) \
case X86::FROM: \
Opc = X86::TO; \
break;
switch (Opc) {
default:
llvm_unreachable("Unreachable!");
FROM_TO(BLENDPDrri, MOVSDrr)
FROM_TO(BLENDPSrri, MOVSSrr)
FROM_TO(VBLENDPDrri, VMOVSDrr)
FROM_TO(VBLENDPSrri, VMOVSSrr)
}
WorkingMI = CloneIfNew(MI);
WorkingMI->setDesc(get(Opc));
WorkingMI->removeOperand(3);
break;
}
#undef FROM_TO
}
[[fallthrough]];
case X86::PBLENDWrri:

9
llvm/test/CodeGen/X86/commute-blend-avx2.ll
View File

@ -88,3 +88,12 @@ define <4 x double> @commute_fold_vblendpd_256(<4 x double> %a, ptr %b) #0 {
ret <4 x double> %2
}
declare <4 x double> @llvm.x86.avx.blend.pd.256(<4 x double>, <4 x double>, i8) nounwind readnone
define <4 x float> @commute_vblendpd_128_for_code_size(<4 x float> %a, <4 x float> %b) optsize {
; CHECK-LABEL: commute_vblendpd_128_for_code_size:
; CHECK: # %bb.0:
; CHECK-NEXT: vblendps {{.*#+}} xmm0 = xmm1[0],xmm0[1],xmm1[2,3]
; CHECK-NEXT: retq
%r = shufflevector <4 x float> %b, <4 x float> %a, <4 x i32> <i32 0, i32 5, i32 2, i32 3>
ret <4 x float> %r
}