diff --git a/lib/Transforms/Scalar/LoopUnswitch.cpp b/lib/Transforms/Scalar/LoopUnswitch.cpp index 5fea7cbea91..61510a71003 100644 --- a/lib/Transforms/Scalar/LoopUnswitch.cpp +++ b/lib/Transforms/Scalar/LoopUnswitch.cpp @@ -396,7 +396,7 @@ BasicBlock *LoopUnswitch::SplitBlock(BasicBlock *Old, Instruction *SplitPt) { // The new block lives in whichever loop the old one did. if (Loop *L = LI->getLoopFor(Old)) L->addBasicBlockToLoop(New, *LI); - + return New; } @@ -413,8 +413,30 @@ BasicBlock *LoopUnswitch::SplitEdge(BasicBlock *BB, BasicBlock *Succ) { } // If this is a critical edge, let SplitCriticalEdge do it. - if (SplitCriticalEdge(BB->getTerminator(), SuccNum, this)) - return LatchTerm->getSuccessor(SuccNum); + Loop *OrigDestBBL = LI->getLoopFor(BB->getTerminator()->getSuccessor(SuccNum)); + if (SplitCriticalEdge(BB->getTerminator(), SuccNum)) { + BasicBlock *NewBB = LatchTerm->getSuccessor(SuccNum); + + Loop *BBL = LI->getLoopFor(BB); + if (!BBL || !OrigDestBBL) + return NewBB; + + // If edge is inside a loop then NewBB is part of same loop. + if (BBL == OrigDestBBL) + BBL->addBasicBlockToLoop(NewBB, *LI); + // If edge is entering loop then NewBB is part of outer loop. + else if (BBL->contains(OrigDestBBL->getHeader())) + BBL->addBasicBlockToLoop(NewBB, *LI); + // If edge is from an inner loop to outer loop then NewBB is part + // of outer loop. + else if (OrigDestBBL->contains(BBL->getHeader())) + OrigDestBBL->addBasicBlockToLoop(NewBB, *LI); + // Else edge is connecting two loops and NewBB is part of their parent loop + else if (Loop *PL = OrigDestBBL->getParentLoop()) + PL->addBasicBlockToLoop(NewBB, *LI); + + return NewBB; + } // If the edge isn't critical, then BB has a single successor or Succ has a // single pred. Split the block. @@ -571,8 +593,6 @@ void LoopUnswitch::UnswitchNontrivialCondition(Value *LIC, Constant *Val, std::vector Preds(pred_begin(ExitBlock), pred_end(ExitBlock)); for (unsigned j = 0, e = Preds.size(); j != e; ++j) { - assert(L->contains(Preds[j]) && - "All preds of loop exit blocks must be the same loop!"); BasicBlock* MiddleBlock = SplitEdge(Preds[j], ExitBlock); BasicBlock* StartBlock = Preds[j]; BasicBlock* EndBlock;