Ejemplo n.º 1
0
MachineBasicBlock::iterator
Filler::findDelayInstr(MachineBasicBlock &MBB,
                       MachineBasicBlock::iterator slot)
{
  SmallSet<unsigned, 32> RegDefs;
  SmallSet<unsigned, 32> RegUses;
  bool sawLoad = false;
  bool sawStore = false;

  if (slot == MBB.begin())
    return MBB.end();

  if (slot->getOpcode() == SP::RET || slot->getOpcode() == SP::TLS_CALL)
    return MBB.end();

  if (slot->getOpcode() == SP::RETL) {
    MachineBasicBlock::iterator J = slot;
    --J;

    if (J->getOpcode() == SP::RESTORErr
        || J->getOpcode() == SP::RESTOREri) {
      // change retl to ret.
      slot->setDesc(TM.getInstrInfo()->get(SP::RET));
      return J;
    }
  }

  // Call's delay filler can def some of call's uses.
  if (slot->isCall())
    insertCallDefsUses(slot, RegDefs, RegUses);
  else
    insertDefsUses(slot, RegDefs, RegUses);

  bool done = false;

  MachineBasicBlock::iterator I = slot;

  while (!done) {
    done = (I == MBB.begin());

    if (!done)
      --I;

    // skip debug value
    if (I->isDebugValue())
      continue;

    if (I->hasUnmodeledSideEffects() || I->isInlineAsm() || I->isPosition() ||
        I->hasDelaySlot() || I->isBundledWithSucc())
      break;

    if (delayHasHazard(I, sawLoad, sawStore, RegDefs, RegUses)) {
      insertDefsUses(I, RegDefs, RegUses);
      continue;
    }

    return I;
  }
  return MBB.end();
}
Ejemplo n.º 2
0
MachineBasicBlock::iterator
MachineBasicBlock::SkipPHIsAndLabels(MachineBasicBlock::iterator I) {
  iterator E = end();
  while (I != E && (I->isPHI() || I->isPosition() || I->isDebugValue()))
    ++I;
  // FIXME: This needs to change if we wish to bundle labels / dbg_values
  // inside the bundle.
  assert((I == E || !I->isInsideBundle()) &&
         "First non-phi / non-label instruction is inside a bundle!");
  return I;
}