diff options
Diffstat (limited to 'llvm/lib/Transforms/Utils/LoopSimplify.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Utils/LoopSimplify.cpp | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/llvm/lib/Transforms/Utils/LoopSimplify.cpp b/llvm/lib/Transforms/Utils/LoopSimplify.cpp index 11d7a21d3ce..1298011e78a 100644 --- a/llvm/lib/Transforms/Utils/LoopSimplify.cpp +++ b/llvm/lib/Transforms/Utils/LoopSimplify.cpp @@ -142,6 +142,8 @@ BasicBlock *llvm::InsertPreheaderForLoop(Loop *L, Pass *PP) { BasicBlock *PreheaderBB; PreheaderBB = SplitBlockPredecessors(Header, OutsideBlocks, ".preheader", DT, LI, PreserveLCSSA); + if (!PreheaderBB) + return nullptr; DEBUG(dbgs() << "LoopSimplify: Creating pre-header " << PreheaderBB->getName() << "\n"); @@ -178,6 +180,8 @@ static BasicBlock *rewriteLoopExitBlock(Loop *L, BasicBlock *Exit, NewExitBB = SplitBlockPredecessors(Exit, LoopBlocks, ".loopexit", DT, LI, PreserveLCSSA); + if (!NewExitBB) + return nullptr; DEBUG(dbgs() << "LoopSimplify: Creating dedicated exit block " << NewExitBB->getName() << "\n"); @@ -256,8 +260,10 @@ static Loop *separateNestedLoop(Loop *L, BasicBlock *Preheader, return nullptr; // The header is not a landing pad; preheader insertion should ensure this. - assert(!L->getHeader()->isLandingPad() && - "Can't insert backedge to landing pad"); + BasicBlock *Header = L->getHeader(); + assert(!Header->isLandingPad() && "Can't insert backedge to landing pad"); + if (!Header->canSplitPredecessors()) + return nullptr; PHINode *PN = findPHIToPartitionLoops(L, DT, AC); if (!PN) return nullptr; // No known way to partition. @@ -285,7 +291,6 @@ static Loop *separateNestedLoop(Loop *L, BasicBlock *Preheader, bool PreserveLCSSA = PP->mustPreserveAnalysisID(LCSSAID); - BasicBlock *Header = L->getHeader(); BasicBlock *NewBB = SplitBlockPredecessors(Header, OuterLoopPreds, ".outer", DT, LI, PreserveLCSSA); |
