diff options
| -rw-r--r-- | lib/CodeGen/InlineSpiller.cpp | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/lib/CodeGen/InlineSpiller.cpp b/lib/CodeGen/InlineSpiller.cpp index fc6d3ec70e..32fb4430b3 100644 --- a/lib/CodeGen/InlineSpiller.cpp +++ b/lib/CodeGen/InlineSpiller.cpp @@ -59,6 +59,8 @@ public: 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); }; @@ -146,6 +148,37 @@ bool InlineSpiller::reMaterialize(LiveInterval &NewLI, 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) { @@ -208,6 +241,10 @@ void InlineSpiller::spill(LiveInterval *li, // 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); |