// Defs others than 2-addr redefs _do_ trigger flag changes:
// - A def followed by a def is dead
// - A use followed by a def is a kill
- if (MO.isReg() && MO.getReg() && MO.isDef() &&
- !I->isRegReDefinedByTwoAddr(MO.getReg())) {
+ if (MO.isReg() && MO.getReg() && MO.isDef()) {
std::map<unsigned, std::pair<MachineInstr*, unsigned> >::iterator
last = LastUseDef.find(MO.getReg());
if (last != LastUseDef.end()) {
+
+ // If this is a two address instr, then we don't mark the def
+ // as killing the use.
+ if (last->second.first == I &&
+ I->getDesc().getOperandConstraint(last->second.second,
+ TOI::TIED_TO) == (signed)i) {
+ LastUseDef[MO.getReg()] = std::make_pair(I, i);
+ continue;
+ }
+
+
MachineOperand& lastUD =
last->second.first->getOperand(last->second.second);
+
if (lastUD.isDef())
lastUD.setIsDead(true);
else if (lastUD.isUse())