if (auto *BA =
dyn_cast<BlockAddress>(IBI->getAddress()->stripPointerCasts())) {
BasicBlock *TheOnlyDest = BA->getBasicBlock();
- std::vector <DominatorTree::UpdateType> Updates;
- if (DTU)
- Updates.reserve(IBI->getNumDestinations() - 1);
+ SmallSetVector<BasicBlock *, 8> RemovedSuccessors;
// Insert the new branch.
Builder.CreateBr(TheOnlyDest);
+ BasicBlock *SuccToKeep = TheOnlyDest;
for (unsigned i = 0, e = IBI->getNumDestinations(); i != e; ++i) {
- if (IBI->getDestination(i) == TheOnlyDest) {
- TheOnlyDest = nullptr;
+ BasicBlock *DestBB = IBI->getDestination(i);
+ if (DTU && DestBB != TheOnlyDest)
+ RemovedSuccessors.insert(DestBB);
+ if (IBI->getDestination(i) == SuccToKeep) {
+ SuccToKeep = nullptr;
} else {
- BasicBlock *ParentBB = IBI->getParent();
- BasicBlock *DestBB = IBI->getDestination(i);
- DestBB->removePredecessor(ParentBB);
- if (DTU)
- Updates.push_back({DominatorTree::Delete, ParentBB, DestBB});
+ DestBB->removePredecessor(BB);
}
}
Value *Address = IBI->getAddress();
// If we didn't find our destination in the IBI successor list, then we
// have undefined behavior. Replace the unconditional branch with an
// 'unreachable' instruction.
- if (TheOnlyDest) {
+ if (SuccToKeep) {
BB->getTerminator()->eraseFromParent();
new UnreachableInst(BB->getContext(), BB);
}
- if (DTU)
- DTU->applyUpdatesPermissive(Updates);
+ if (DTU) {
+ std::vector<DominatorTree::UpdateType> Updates;
+ Updates.reserve(RemovedSuccessors.size());
+ for (auto *RemovedSuccessor : RemovedSuccessors)
+ Updates.push_back({DominatorTree::Delete, BB, RemovedSuccessor});
+ DTU->applyUpdates(Updates);
+ }
return true;
}
}