SmallVectorImpl<LiveInterval*> &spillIs,
SlotIndex *earliestIndex);
bool reMaterialize(LiveInterval &NewLI, MachineBasicBlock::iterator MI);
+ bool foldMemoryOperand(MachineBasicBlock::iterator MI,
+ const SmallVectorImpl<unsigned> &Ops);
void insertReload(LiveInterval &NewLI, MachineBasicBlock::iterator MI);
void insertSpill(LiveInterval &NewLI, MachineBasicBlock::iterator MI);
};
return true;
}
+/// foldMemoryOperand - Try folding stack slot references in Ops into MI.
+/// Return true on success, and MI will be erased.
+bool InlineSpiller::foldMemoryOperand(MachineBasicBlock::iterator MI,
+ const SmallVectorImpl<unsigned> &Ops) {
+ // TargetInstrInfo::foldMemoryOperand only expects explicit, non-tied
+ // operands.
+ SmallVector<unsigned, 8> FoldOps;
+ for (unsigned i = 0, e = Ops.size(); i != e; ++i) {
+ unsigned Idx = Ops[i];
+ MachineOperand &MO = MI->getOperand(Idx);
+ if (MO.isImplicit())
+ continue;
+ // FIXME: Teach targets to deal with subregs.
+ if (MO.getSubReg())
+ return false;
+ // Tied use operands should not be passed to foldMemoryOperand.
+ if (!MI->isRegTiedToDefOperand(Idx))
+ FoldOps.push_back(Idx);
+ }
+
+ MachineInstr *FoldMI = tii_.foldMemoryOperand(mf_, MI, FoldOps, stackSlot_);
+ if (!FoldMI)
+ return false;
+ MachineBasicBlock &MBB = *MI->getParent();
+ lis_.ReplaceMachineInstrInMaps(MI, FoldMI);
+ vrm_.addSpillSlotUse(stackSlot_, FoldMI);
+ MBB.insert(MBB.erase(MI), FoldMI);
+ DEBUG(dbgs() << "\tfolded: " << *FoldMI);
+ return true;
+}
+
/// insertReload - Insert a reload of NewLI.reg before MI.
void InlineSpiller::insertReload(LiveInterval &NewLI,
MachineBasicBlock::iterator MI) {
// Attempt remat instead of reload.
bool NeedsReload = Reads && !reMaterialize(NewLI, MI);
+ // Attempt to fold memory ops.
+ if (NewLI.empty() && foldMemoryOperand(MI, Ops))
+ continue;
+
if (NeedsReload)
insertReload(NewLI, MI);