- vector<BasicBlock*> ReturningBlocks;
- for(Function::iterator I = M->begin(), E = M->end(); I != E; ++I)
- if (isa<ReturnInst>((*I)->getTerminator()))
- ReturningBlocks.push_back(*I);
+ std::vector<BasicBlock*> ReturningBlocks;
+ std::vector<BasicBlock*> UnreachableBlocks;
+ for(Function::iterator I = F.begin(), E = F.end(); I != E; ++I)
+ if (isa<ReturnInst>(I->getTerminator()))
+ ReturningBlocks.push_back(I);
+ else if (isa<UnreachableInst>(I->getTerminator()))
+ UnreachableBlocks.push_back(I);
+
+ // Then unreachable blocks.
+ if (UnreachableBlocks.empty()) {
+ UnreachableBlock = nullptr;
+ } else if (UnreachableBlocks.size() == 1) {
+ UnreachableBlock = UnreachableBlocks.front();
+ } else {
+ UnreachableBlock = BasicBlock::Create(F.getContext(),
+ "UnifiedUnreachableBlock", &F);
+ new UnreachableInst(F.getContext(), UnreachableBlock);
+
+ for (std::vector<BasicBlock*>::iterator I = UnreachableBlocks.begin(),
+ E = UnreachableBlocks.end(); I != E; ++I) {
+ BasicBlock *BB = *I;
+ BB->getInstList().pop_back(); // Remove the unreachable inst.
+ BranchInst::Create(UnreachableBlock, BB);
+ }
+ }