void handlePhysicalRegisterDef(MachineBasicBlock* mbb,
MachineBasicBlock::iterator mi,
LiveInterval& interval,
- unsigned SrcReg, unsigned DestReg);
+ unsigned SrcReg, unsigned DestReg,
+ bool isLiveIn = false);
/// Return true if the two specified registers belong to different
/// register classes. The registers may be either phys or virt regs.
for (MachineFunction::livein_iterator I = fn.livein_begin(),
E = fn.livein_end(); I != E; ++I) {
handlePhysicalRegisterDef(Entry, Entry->begin(),
- getOrCreateInterval(I->first), 0, 0);
+ getOrCreateInterval(I->first), 0, 0, true);
for (const unsigned* AS = mri_->getAliasSet(I->first); *AS; ++AS)
handlePhysicalRegisterDef(Entry, Entry->begin(),
- getOrCreateInterval(*AS), 0, 0);
+ getOrCreateInterval(*AS), 0, 0, true);
}
}
void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock *MBB,
MachineBasicBlock::iterator mi,
LiveInterval& interval,
- unsigned SrcReg, unsigned DestReg)
+ unsigned SrcReg, unsigned DestReg,
+ bool isLiveIn)
{
// A physical register cannot be live across basic block, so its
// lifetime must end somewhere in its defining basic block.
// If it is not dead on definition, it must be killed by a
// subsequent instruction. Hence its interval is:
// [defSlot(def), useSlot(kill)+1)
- while (true) {
- ++mi;
- assert(mi != MBB->end() && "physreg was not killed in defining block!");
+ while (++mi != MBB->end()) {
baseIndex += InstrSlots::NUM;
if (lv_->KillsRegister(mi, interval.reg)) {
DEBUG(std::cerr << " killed");
goto exit;
}
}
+
+ // The only case we should have a dead physreg here without a killing or
+ // instruction where we know it's dead is if it is live-in to the function
+ // and never used.
+ assert(isLiveIn && "physreg was not killed in defining block!");
+ end = getDefIndex(start) + 1; // It's dead.
exit:
assert(start < end && "did not find end of interval?");
void handlePhysicalRegisterDef(MachineBasicBlock* mbb,
MachineBasicBlock::iterator mi,
LiveInterval& interval,
- unsigned SrcReg, unsigned DestReg);
+ unsigned SrcReg, unsigned DestReg,
+ bool isLiveIn = false);
/// Return true if the two specified registers belong to different
/// register classes. The registers may be either phys or virt regs.