本文整理汇总了C++中machinebasicblock::iterator::isRegTiedToDefOperand方法的典型用法代码示例。如果您正苦于以下问题:C++ iterator::isRegTiedToDefOperand方法的具体用法?C++ iterator::isRegTiedToDefOperand怎么用?C++ iterator::isRegTiedToDefOperand使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类machinebasicblock::iterator
的用法示例。
在下文中一共展示了iterator::isRegTiedToDefOperand方法的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: foldMemoryOperand
/// 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(MI, FoldOps, stackSlot_);
if (!FoldMI)
return false;
lis_.ReplaceMachineInstrInMaps(MI, FoldMI);
vrm_.addSpillSlotUse(stackSlot_, FoldMI);
MI->eraseFromParent();
DEBUG(dbgs() << "\tfolded: " << *FoldMI);
return true;
}
示例2: reMaterializeFor
/// reMaterializeFor - Attempt to rematerialize li_->reg before MI instead of
/// reloading it.
bool InlineSpiller::reMaterializeFor(MachineBasicBlock::iterator MI) {
SlotIndex UseIdx = lis_.getInstructionIndex(MI).getUseIndex();
VNInfo *OrigVNI = li_->getVNInfoAt(UseIdx);
if (!OrigVNI) {
DEBUG(dbgs() << "\tadding <undef> flags: ");
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
MachineOperand &MO = MI->getOperand(i);
if (MO.isReg() && MO.isUse() && MO.getReg() == li_->reg)
MO.setIsUndef();
}
DEBUG(dbgs() << UseIdx << '\t' << *MI);
return true;
}
if (!reMattable_.count(OrigVNI)) {
DEBUG(dbgs() << "\tusing non-remat valno " << OrigVNI->id << ": "
<< UseIdx << '\t' << *MI);
return false;
}
MachineInstr *OrigMI = lis_.getInstructionFromIndex(OrigVNI->def);
if (!allUsesAvailableAt(OrigMI, OrigVNI->def, UseIdx)) {
usedValues_.insert(OrigVNI);
DEBUG(dbgs() << "\tcannot remat for " << UseIdx << '\t' << *MI);
return false;
}
// If the instruction also writes li_->reg, it had better not require the same
// register for uses and defs.
bool Reads, Writes;
SmallVector<unsigned, 8> Ops;
tie(Reads, Writes) = MI->readsWritesVirtualRegister(li_->reg, &Ops);
if (Writes) {
for (unsigned i = 0, e = Ops.size(); i != e; ++i) {
MachineOperand &MO = MI->getOperand(Ops[i]);
if (MO.isUse() ? MI->isRegTiedToDefOperand(Ops[i]) : MO.getSubReg()) {
usedValues_.insert(OrigVNI);
DEBUG(dbgs() << "\tcannot remat tied reg: " << UseIdx << '\t' << *MI);
return false;
}
}
}
// Alocate a new register for the remat.
unsigned NewVReg = mri_.createVirtualRegister(rc_);
vrm_.grow();
LiveInterval &NewLI = lis_.getOrCreateInterval(NewVReg);
NewLI.markNotSpillable();
newIntervals_->push_back(&NewLI);
// Finally we can rematerialize OrigMI before MI.
MachineBasicBlock &MBB = *MI->getParent();
tii_.reMaterialize(MBB, MI, NewLI.reg, 0, OrigMI, tri_);
MachineBasicBlock::iterator RematMI = MI;
SlotIndex DefIdx = lis_.InsertMachineInstrInMaps(--RematMI).getDefIndex();
DEBUG(dbgs() << "\tremat: " << DefIdx << '\t' << *RematMI);
// Replace operands
for (unsigned i = 0, e = Ops.size(); i != e; ++i) {
MachineOperand &MO = MI->getOperand(Ops[i]);
if (MO.isReg() && MO.isUse() && MO.getReg() == li_->reg) {
MO.setReg(NewVReg);
MO.setIsKill();
}
}
DEBUG(dbgs() << "\t " << UseIdx << '\t' << *MI);
VNInfo *DefVNI = NewLI.getNextValue(DefIdx, 0, true,
lis_.getVNInfoAllocator());
NewLI.addRange(LiveRange(DefIdx, UseIdx.getDefIndex(), DefVNI));
DEBUG(dbgs() << "\tinterval: " << NewLI << '\n');
return true;
}