[NFC] Tweak SplitBlockAndInsertIfThen to use existing ThenBlock
llvm-svn: 354107
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 5ca9222..6f49eae 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -730,18 +730,23 @@
Instruction *SplitBefore,
bool Unreachable,
MDNode *BranchWeights,
- DominatorTree *DT, LoopInfo *LI) {
+ DominatorTree *DT, LoopInfo *LI,
+ BasicBlock *ThenBlock) {
BasicBlock *Head = SplitBefore->getParent();
BasicBlock *Tail = Head->splitBasicBlock(SplitBefore->getIterator());
Instruction *HeadOldTerm = Head->getTerminator();
LLVMContext &C = Head->getContext();
- BasicBlock *ThenBlock = BasicBlock::Create(C, "", Head->getParent(), Tail);
Instruction *CheckTerm;
- if (Unreachable)
- CheckTerm = new UnreachableInst(C, ThenBlock);
- else
- CheckTerm = BranchInst::Create(Tail, ThenBlock);
- CheckTerm->setDebugLoc(SplitBefore->getDebugLoc());
+ bool CreateThenBlock = (ThenBlock == nullptr);
+ if (CreateThenBlock) {
+ ThenBlock = BasicBlock::Create(C, "", Head->getParent(), Tail);
+ if (Unreachable)
+ CheckTerm = new UnreachableInst(C, ThenBlock);
+ else
+ CheckTerm = BranchInst::Create(Tail, ThenBlock);
+ CheckTerm->setDebugLoc(SplitBefore->getDebugLoc());
+ } else
+ CheckTerm = ThenBlock->getTerminator();
BranchInst *HeadNewTerm =
BranchInst::Create(/*ifTrue*/ThenBlock, /*ifFalse*/Tail, Cond);
HeadNewTerm->setMetadata(LLVMContext::MD_prof, BranchWeights);
@@ -756,7 +761,10 @@
DT->changeImmediateDominator(Child, NewNode);
// Head dominates ThenBlock.
- DT->addNewBlock(ThenBlock, Head);
+ if (CreateThenBlock)
+ DT->addNewBlock(ThenBlock, Head);
+ else
+ DT->changeImmediateDominator(ThenBlock, Head);
}
}