// trivially dominate itself, which would lead us to rewriting its
// argument in terms of its return value, which would lead to
// infinite loops in GetArgRCIdentityRoot.
- if (DT->isReachableFromEntry(U) && DT->dominates(Inst, U)) {
- Changed = true;
- Instruction *Replacement = Inst;
- Type *UseTy = U.get()->getType();
- if (PHINode *PHI = dyn_cast<PHINode>(U.getUser())) {
- // For PHI nodes, insert the bitcast in the predecessor block.
- unsigned ValNo = PHINode::getIncomingValueNumForOperand(OperandNo);
- BasicBlock *BB = PHI->getIncomingBlock(ValNo);
- if (Replacement->getType() != UseTy)
- Replacement = new BitCastInst(Replacement, UseTy, "",
- &BB->back());
- // While we're here, rewrite all edges for this PHI, rather
- // than just one use at a time, to minimize the number of
- // bitcasts we emit.
- for (unsigned i = 0, e = PHI->getNumIncomingValues(); i != e; ++i)
- if (PHI->getIncomingBlock(i) == BB) {
- // Keep the UI iterator valid.
- if (UI != UE &&
- &PHI->getOperandUse(
- PHINode::getOperandNumForIncomingValue(i)) == &*UI)
- ++UI;
- PHI->setIncomingValue(i, Replacement);
- }
- } else {
- if (Replacement->getType() != UseTy)
- Replacement = new BitCastInst(Replacement, UseTy, "",
- cast<Instruction>(U.getUser()));
- U.set(Replacement);
- }
+ if (!DT->isReachableFromEntry(U) || !DT->dominates(Inst, U))
+ continue;
+
+ Changed = true;
+ Instruction *Replacement = Inst;
+ Type *UseTy = U.get()->getType();
+ if (PHINode *PHI = dyn_cast<PHINode>(U.getUser())) {
+ // For PHI nodes, insert the bitcast in the predecessor block.
+ unsigned ValNo = PHINode::getIncomingValueNumForOperand(OperandNo);
+ BasicBlock *BB = PHI->getIncomingBlock(ValNo);
+ if (Replacement->getType() != UseTy)
+ Replacement = new BitCastInst(Replacement, UseTy, "", &BB->back());
+ // While we're here, rewrite all edges for this PHI, rather
+ // than just one use at a time, to minimize the number of
+ // bitcasts we emit.
+ for (unsigned i = 0, e = PHI->getNumIncomingValues(); i != e; ++i)
+ if (PHI->getIncomingBlock(i) == BB) {
+ // Keep the UI iterator valid.
+ if (UI != UE &&
+ &PHI->getOperandUse(
+ PHINode::getOperandNumForIncomingValue(i)) == &*UI)
+ ++UI;
+ PHI->setIncomingValue(i, Replacement);
+ }
+ } else {
+ if (Replacement->getType() != UseTy)
+ Replacement = new BitCastInst(Replacement, UseTy, "",
+ cast<Instruction>(U.getUser()));
+ U.set(Replacement);
}
}
};