MachineBasicBlock::iterator
Filler::findDelayInstr(MachineBasicBlock &MBB,
MachineBasicBlock::iterator slot)
{
SmallSet<unsigned, 32> RegDefs;
SmallSet<unsigned, 32> RegUses;
bool sawLoad = false;
bool sawStore = false;
MachineBasicBlock::iterator I = slot;
if (slot->getOpcode() == SP::RET)
return MBB.end();
if (slot->getOpcode() == SP::RETL) {
--I;
if (I->getOpcode() != SP::RESTORErr)
return MBB.end();
//change retl to ret
slot->setDesc(TII->get(SP::RET));
return I;
}
//Call's delay filler can def some of call's uses.
if (slot->isCall())
insertCallUses(slot, RegUses);
else
insertDefsUses(slot, RegDefs, RegUses);
bool done = false;
while (!done) {
done = (I == MBB.begin());
if (!done)
--I;
// skip debug value
if (I->isDebugValue())
continue;
if (I->hasUnmodeledSideEffects()
|| I->isInlineAsm()
|| I->isLabel()
|| I->hasDelaySlot()
|| isDelayFiller(MBB, I))
break;
if (delayHasHazard(I, sawLoad, sawStore, RegDefs, RegUses)) {
insertDefsUses(I, RegDefs, RegUses);
continue;
}
return I;
}
return MBB.end();
}
// SkipPHIsAndLabels - Copies need to be inserted after phi nodes and
// also after any exception handling labels: in landing pads execution
// starts at the label, so any copies placed before it won't be executed!
MachineBasicBlock::iterator SkipPHIsAndLabels(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I) {
// Rather than assuming that EH labels come before other kinds of labels,
// just skip all labels.
while (I != MBB.end() &&
(I->getOpcode() == TargetInstrInfo::PHI || I->isLabel()))
++I;
return I;
}
MachineBasicBlock::iterator
MachineBasicBlock::SkipPHIsAndLabels(MachineBasicBlock::iterator I) {
while (I != end() && (I->isPHI() || I->isLabel() || I->isDebugValue()))
++I;
// FIXME: This needs to change if we wish to bundle labels / dbg_values
// inside the bundle.
assert(!I->isInsideBundle() &&
"First non-phi / non-label instruction is inside a bundle!");
return I;
}
MachineBasicBlock::iterator
MachineBasicBlock::SkipPHIsAndLabels(MachineBasicBlock::iterator I) {
while (I != end() && (I->isPHI() || I->isLabel() || I->isDebugValue()))
++I;
return I;
}