It's not safe eliminate copies where src and dst have different sub-register indices.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103450 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/ProcessImplicitDefs.cpp b/lib/CodeGen/ProcessImplicitDefs.cpp
index 75875d2..62f525f 100644
--- a/lib/CodeGen/ProcessImplicitDefs.cpp
+++ b/lib/CodeGen/ProcessImplicitDefs.cpp
@@ -46,7 +46,7 @@
const TargetInstrInfo *tii_) {
unsigned SrcReg, DstReg, SrcSubReg, DstSubReg;
if (tii_->isMoveInstr(*MI, SrcReg, DstReg, SrcSubReg, DstSubReg) &&
- Reg == SrcReg)
+ Reg == SrcReg && SrcSubReg == 0 && DstSubReg == 0)
return true;
if (OpIdx == 2 && MI->isSubregToReg())
@@ -220,7 +220,7 @@
// Turn a copy use into an implicit_def.
unsigned SrcReg, DstReg, SrcSubReg, DstSubReg;
if (tii_->isMoveInstr(*RMI, SrcReg, DstReg, SrcSubReg, DstSubReg) &&
- Reg == SrcReg) {
+ Reg == SrcReg && SrcSubReg == 0 && DstSubReg == 0) {
RMI->setDesc(tii_->get(TargetOpcode::IMPLICIT_DEF));
bool isKill = false;