diff options
Diffstat (limited to 'llvm/lib/Transforms/Utils/SimplifyCFG.cpp')
-rw-r--r-- | llvm/lib/Transforms/Utils/SimplifyCFG.cpp | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp index 2f575b9d502..e625766477d 100644 --- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp @@ -3055,6 +3055,15 @@ static bool mergeConditionalStores(BranchInst *PBI, BranchInst *QBI) { BasicBlock *QFB = QBI->getSuccessor(1); BasicBlock *PostBB = QFB->getSingleSuccessor(); + // Make sure we have a good guess for PostBB. If QTB's only successor is + // QFB, then QFB is a better PostBB. + if (QTB->getSingleSuccessor() == QFB) + PostBB = QFB; + + // If we couldn't find a good PostBB, stop. + if (!PostBB) + return false; + bool InvertPCond = false, InvertQCond = false; // Canonicalize fallthroughs to the true branches. if (PFB == QBI->getParent()) { @@ -3079,8 +3088,7 @@ static bool mergeConditionalStores(BranchInst *PBI, BranchInst *QBI) { auto HasOnePredAndOneSucc = [](BasicBlock *BB, BasicBlock *P, BasicBlock *S) { return BB->getSinglePredecessor() == P && BB->getSingleSuccessor() == S; }; - if (!PostBB || - !HasOnePredAndOneSucc(PFB, PBI->getParent(), QBI->getParent()) || + if (!HasOnePredAndOneSucc(PFB, PBI->getParent(), QBI->getParent()) || !HasOnePredAndOneSucc(QFB, QBI->getParent(), PostBB)) return false; if ((PTB && !HasOnePredAndOneSucc(PTB, PBI->getParent(), QBI->getParent())) || |