Index: lib/Target/X86/X86DomainReassignment.cpp =================================================================== --- lib/Target/X86/X86DomainReassignment.cpp +++ lib/Target/X86/X86DomainReassignment.cpp @@ -262,25 +262,6 @@ } }; -/// 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 typedef std::pair InstrConverterBaseKeyTy; @@ -587,7 +568,7 @@ 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); Index: test/CodeGen/X86/domain-reassignment-implicit-def.ll =================================================================== --- /dev/null +++ test/CodeGen/X86/domain-reassignment-implicit-def.ll @@ -0,0 +1,25 @@ +; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py +; 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 +}