Index: llvm/lib/Target/PowerPC/PPCInstrInfo.cpp =================================================================== --- llvm/lib/Target/PowerPC/PPCInstrInfo.cpp +++ llvm/lib/Target/PowerPC/PPCInstrInfo.cpp @@ -3205,9 +3205,9 @@ } assert((&*It) == &DefMI && "DefMI is missing"); - // If DefMI also uses the register to be forwarded, we can only forward it + // If DefMI also defines the register to be forwarded, we can only forward it // if DefMI is being erased. - if (DefMI.readsRegister(Reg, &getRegisterInfo())) + if (DefMI.modifiesRegister(Reg, &getRegisterInfo())) return KillDefMI; return true; Index: llvm/test/CodeGen/PowerPC/convert-rr-to-ri-instr-add.mir =================================================================== --- /dev/null +++ llvm/test/CodeGen/PowerPC/convert-rr-to-ri-instr-add.mir @@ -0,0 +1,17 @@ +# RUN: llc -mtriple=powerpc64le--linux-gnu -stop-after ppc-pre-emit-peephole %s -o - -verify-machineinstrs | FileCheck %s + +--- +; ADDI8 + STFSX can be converted to ADDI8 + STFS even ADDI8 can not be erased. +name: testFwdOperandKilledAfter +# CHECK: name: testFwdOperandKilledAfter +tracksRegLiveness: true +body: | + bb.0.entry: + liveins: $x3, $f1, $x5 + $x3 = ADDI8 $x5, 100 + STFSX killed $f1, $zero8, $x3 + ; CHECK: STFS killed $f1, 100, $x5 + STD killed $x3, killed $x5, 100 + ; CHECK: STD killed $x3, killed $x5, 100 + BLR8 implicit $lr8, implicit $rm +...