Let callers decide the sub-register index on the def operand of rematerialized instructions.
Avoid remat'ing instructions whose def have sub-register indices for now. It's just really really hard to get all the cases right.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75900 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86InstrInfo.cpp b/lib/Target/X86/X86InstrInfo.cpp
index 6f5e717..6e1d079 100644
--- a/lib/Target/X86/X86InstrInfo.cpp
+++ b/lib/Target/X86/X86InstrInfo.cpp
@@ -916,14 +916,11 @@
void X86InstrInfo::reMaterialize(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
- unsigned DestReg,
+ unsigned DestReg, unsigned SubIdx,
const MachineInstr *Orig) const {
DebugLoc DL = DebugLoc::getUnknownLoc();
if (I != MBB.end()) DL = I->getDebugLoc();
- unsigned SubIdx = Orig->getOperand(0).isReg()
- ? Orig->getOperand(0).getSubReg() : 0;
- bool ChangeSubIdx = SubIdx != 0;
if (SubIdx && TargetRegisterInfo::isPhysicalRegister(DestReg)) {
DestReg = RI.getSubReg(DestReg, SubIdx);
SubIdx = 0;
@@ -931,37 +928,36 @@
// MOV32r0 etc. are implemented with xor which clobbers condition code.
// Re-materialize them as movri instructions to avoid side effects.
- bool Emitted = false;
- switch (Orig->getOpcode()) {
+ bool Clone = true;
+ unsigned Opc = Orig->getOpcode();
+ switch (Opc) {
default: break;
case X86::MOV8r0:
case X86::MOV16r0:
case X86::MOV32r0: {
if (!isSafeToClobberEFLAGS(MBB, I)) {
- unsigned Opc = 0;
- switch (Orig->getOpcode()) {
+ switch (Opc) {
default: break;
case X86::MOV8r0: Opc = X86::MOV8ri; break;
case X86::MOV16r0: Opc = X86::MOV16ri; break;
case X86::MOV32r0: Opc = X86::MOV32ri; break;
}
- BuildMI(MBB, I, DL, get(Opc), DestReg).addImm(0);
- Emitted = true;
+ Clone = false;
}
break;
}
}
- if (!Emitted) {
+ if (Clone) {
MachineInstr *MI = MBB.getParent()->CloneMachineInstr(Orig);
MI->getOperand(0).setReg(DestReg);
MBB.insert(I, MI);
+ } else {
+ BuildMI(MBB, I, DL, get(Opc), DestReg).addImm(0);
}
- if (ChangeSubIdx) {
- MachineInstr *NewMI = prior(I);
- NewMI->getOperand(0).setSubReg(SubIdx);
- }
+ MachineInstr *NewMI = prior(I);
+ NewMI->getOperand(0).setSubReg(SubIdx);
}
/// isInvariantLoad - Return true if the specified instruction (which is marked