// Live-out (of the function) registers contain return values of the function,
// so we need to make sure they are alive at return time.
- bool BBEndsInReturn = !MBB.empty() && MBB.back().getDesc().isReturn();
- if (BBEndsInReturn) {
- MachineInstr* Ret = &MBB.back();
+ MachineBasicBlock::iterator Ret = MBB.getFirstTerminator();
+ bool BBEndsInReturn = (Ret != MBB.end() && Ret->getDesc().isReturn());
+
+ if (BBEndsInReturn)
for (MachineRegisterInfo::liveout_iterator
I = MF->getRegInfo().liveout_begin(),
E = MF->getRegInfo().liveout_end(); I != E; ++I)
Ret->addOperand(MachineOperand::CreateReg(*I, false, true));
LastUseDef[*I] = std::make_pair(Ret, Ret->getNumOperands()-1);
}
- }
// Finally, loop over the final use/def of each reg
// in the block and determine if it is dead.