diff --git a/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp b/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp --- a/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp +++ b/llvm/lib/Target/PowerPC/PPCInstrInfo.cpp @@ -3141,11 +3141,11 @@ Register InUseReg = MI.getOperand(OpNo).getReg(); MI.getOperand(OpNo).ChangeToImmediate(Imm); - if (MI.implicit_operands().empty()) - return; - // We need to make sure that the MI didn't have any implicit use - // of this REG any more. + // of this REG any more. We don't call MI.implicit_operands().empty() to + // return early, since MI's MCID might be changed in calling context, as a + // result its number of explicit operands may be changed, thus the begin of + // implicit operand is changed. const TargetRegisterInfo *TRI = &getRegisterInfo(); int UseOpIdx = MI.findRegisterUseOperandIdx(InUseReg, false, TRI); if (UseOpIdx >= 0) { diff --git a/llvm/test/CodeGen/PowerPC/remove-redundant-li-implicit-reg.mir b/llvm/test/CodeGen/PowerPC/remove-redundant-li-implicit-reg.mir new file mode 100644 --- /dev/null +++ b/llvm/test/CodeGen/PowerPC/remove-redundant-li-implicit-reg.mir @@ -0,0 +1,22 @@ +# RUN: llc -mtriple=powerpc64-unknown-unknown -stop-after ppc-pre-emit-peephole \ +# RUN: %s -o - -verify-machineinstrs | FileCheck %s + +--- +name: testRedundantLiImplicitReg +tracksRegLiveness: true +body: | + bb.0.entry: + liveins: $x3, $x4, $x5 + + STW killed $r3, killed $x5, 100 + renamable $x5 = LI8 2 + renamable $x4 = exact SRD killed renamable $x4, killed renamable $r5, implicit $x5 + STD $x4, $x4, 100 + BLR8 implicit $lr8, implicit $rm + + ; CHECK-LABEL: testRedundantLiImplicitReg + ; CHECK: bb.0.entry: + ; CHECK: STW killed $r3, killed $x5, 100 + ; CHECK: renamable $x4 = exact RLDICL killed renamable $x4, 62, 2 + ; CHECK: STD killed $x4, $x4, 100 + ; CHECK: BLR8 implicit $lr8, implicit $rm