Magic-Mirror/llvm-capstone
1
0
Fork 0
mirror of https://github.com/capstone-engine/llvm-capstone.git synced 2024-11-28 16:11:29 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

[X86DomainReassignment] Don't delete IMPLICIT_DEF nodes

Browse Source 
Summary:
We cannot simply delete IMPLICIT_DEF nodes. They may be used
later (e.g. by a PHI) and deleting them will cause later passes (e.g.
LiveVariables) to crash. However, it seems fine to ignore them for
purposes of the domain reassignment (as we do with PHI).

Fixes PR37430
Fixes JuliaLang/julia#27080

Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D46797

llvm-svn: 332680
This commit is contained in:
Keno Fischer 2018-05-18 00:40:52 +00:00
parent 3eb71831e5
commit 66ab99c3ee
2 changed files with 25 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
llvm/lib/Target/X86/X86DomainReassignment.cpp
View File

@ -262,25 +262,6 @@ public:
}
};
/// An Instruction Converter which completely deletes an instruction.
/// For example, IMPLICIT_DEF instructions can be deleted when converting from
/// GPR to mask.
class InstrDeleter : public InstrConverterBase {
public:
InstrDeleter(unsigned SrcOpcode) : InstrConverterBase(SrcOpcode) {}
bool convertInstr(MachineInstr *MI, const TargetInstrInfo *TII,
MachineRegisterInfo *MRI) const override {
assert(isLegal(MI, TII) && "Cannot convert instruction");
return true;
}
double getExtraCost(const MachineInstr *MI,
MachineRegisterInfo *MRI) const override {
return 0;
}
};
// Key type to be used by the Instruction Converters map.
// A converter is identified by <destination domain, source opcode>
typedef std::pair<int, unsigned> InstrConverterBaseKeyTy;
@ -587,7 +568,7 @@ void X86DomainReassignment::initConverters() {
new InstrIgnore(TargetOpcode::PHI);
Converters[{MaskDomain, TargetOpcode::IMPLICIT_DEF}] =
new InstrDeleter(TargetOpcode::IMPLICIT_DEF);
new InstrIgnore(TargetOpcode::IMPLICIT_DEF);
Converters[{MaskDomain, TargetOpcode::INSERT_SUBREG}] =
new InstrReplaceWithCopy(TargetOpcode::INSERT_SUBREG, 2);

24
llvm/test/CodeGen/X86/domain-reassignment-implicit-def.ll Normal file
View File

@ -0,0 +1,24 @@
; RUN: llc -mcpu=skylake-avx512 -mtriple=x86_64-unknown-linux-gnu %s -o - | FileCheck %s
; Check that the X86 Domain Reassignment pass doesn't drop IMPLICIT_DEF nodes,
; which would later cause crashes (e.g. in LiveVariables) - see PR37430
define void @domain_reassignment_implicit_def(i1 %cond, i8 *%mem, float %arg) {
; CHECK: vxorps %xmm1, %xmm1, %xmm1
; CHECK: vcmpneqss %xmm1, %xmm0, %k0
; CHECK: kmovb %k0, (%rsi)
top:
br i1 %cond, label %L19, label %L15
L15: ; preds = %top
%tmp47 = fcmp une float 0.000000e+00, %arg
%tmp48 = zext i1 %tmp47 to i8
br label %L21
L19: ; preds = %top
br label %L21
L21: ; preds = %L19, %L15
%.sroa.0.0 = phi i8 [ undef, %L19 ], [ %tmp48, %L15 ]
store i8 %.sroa.0.0, i8* %mem, align 1
ret void
}