Constrain register classes in TailDup.

When rewriting operands, make sure the new registers have a compatible
register class.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157163 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2012-05-20 18:42:51 +00:00
parent 92d63ccfc7
commit 0fda545c2c

View File

@ -272,8 +272,8 @@ TailDuplicatePass::TailDuplicateAndUpdate(MachineBasicBlock *MBB,
continue;
unsigned Dst = Copy->getOperand(0).getReg();
unsigned Src = Copy->getOperand(1).getReg();
MachineRegisterInfo::use_iterator UI = MRI->use_begin(Src);
if (++UI == MRI->use_end()) {
if (MRI->hasOneNonDBGUse(Src) &&
MRI->constrainRegClass(Src, MRI->getRegClass(Dst))) {
// Copy is the only use. Do trivial copy propagation here.
MRI->replaceRegWith(Dst, Src);
Copy->eraseFromParent();
@ -429,8 +429,10 @@ void TailDuplicatePass::DuplicateInstruction(MachineInstr *MI,
AddSSAUpdateEntry(Reg, NewReg, PredBB);
} else {
DenseMap<unsigned, unsigned>::iterator VI = LocalVRMap.find(Reg);
if (VI != LocalVRMap.end())
if (VI != LocalVRMap.end()) {
MO.setReg(VI->second);
MRI->constrainRegClass(VI->second, MRI->getRegClass(Reg));
}
}
}
PredBB->insert(PredBB->instr_end(), NewMI);