diff options
| -rw-r--r-- | lib/VMCore/Dominators.cpp | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/lib/VMCore/Dominators.cpp b/lib/VMCore/Dominators.cpp index f8aef5dde2..9b5ee1bb40 100644 --- a/lib/VMCore/Dominators.cpp +++ b/lib/VMCore/Dominators.cpp @@ -616,7 +616,11 @@ void DominanceFrontier::splitBlock(BasicBlock *NewBB) { PI != PE; ++PI) PredBlocks.push_back(*PI); - assert(!PredBlocks.empty() && "No predblocks??"); + if (PredBlocks.empty()) + // If NewBB does not have any predecessors then it is a entry block. + // In this case, NewBB and its successor NewBBSucc dominates all + // other blocks. + return; DominatorTree &DT = getAnalysis<DominatorTree>(); bool NewBBDominatesNewBBSucc = true; @@ -643,8 +647,13 @@ void DominanceFrontier::splitBlock(BasicBlock *NewBB) { else ++SetI; } - - addBasicBlock(NewBB, Set); + + DominanceFrontier::iterator NewBBI = find(NewBB); + if (NewBBI != end()) { + DominanceFrontier::DomSetType NewBBSet = NewBBI->second; + NewBBSet.insert(Set.begin(), Set.end()); + } else + addBasicBlock(NewBB, Set); } } else { |