}
} else {
// Trim live intervals of input registers. They are no longer live into
- // this block.
+ // this block if they died after the PHI. If they lived after it, don't
+ // trim them because they might have other legitimate uses.
for (unsigned i = 1; i < PInstr->getNumOperands(); i += 2) {
unsigned reg = PInstr->getOperand(i).getReg();
MachineBasicBlock* MBB = PInstr->getOperand(i+1).getMBB();
LiveInterval& InputI = LI.getInterval(reg);
if (MBB != PInstr->getParent() &&
- InputI.liveAt(LI.getMBBStartIdx(PInstr->getParent())))
+ InputI.liveAt(LI.getMBBStartIdx(PInstr->getParent())) &&
+ InputI.expiredAt(LI.getInstructionIndex(PInstr) +
+ LiveIntervals::InstrSlots::NUM))
InputI.removeRange(LI.getMBBStartIdx(PInstr->getParent()),
LI.getInstructionIndex(PInstr),
true);