From 654e130b6ec76c1a2910b2594cb403ecd2773af8 Mon Sep 17 00:00:00 2001 From: David Majnemer Date: Fri, 31 Jul 2015 17:58:14 +0000 Subject: New EH representation for MSVC compatibility This introduces new instructions neccessary to implement MSVC-compatible exception handling support. Most of the middle-end and none of the back-end haven't been audited or updated to take them into account. Differential Revision: http://reviews.llvm.org/D11097 llvm-svn: 243766 --- llvm/lib/Transforms/Utils/BasicBlockUtils.cpp | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'llvm/lib/Transforms/Utils/BasicBlockUtils.cpp') diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp index 74ca0a1aa18..1bf92e35abc 100644 --- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp +++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp @@ -117,8 +117,9 @@ bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DominatorTree *DT, // Don't break self-loops. if (PredBB == BB) return false; - // Don't break invokes. - if (isa(PredBB->getTerminator())) return false; + // Don't break unwinding instructions. + if (PredBB->getTerminator()->isExceptional()) + return false; succ_iterator SI(succ_begin(PredBB)), SE(succ_end(PredBB)); BasicBlock *OnlySucc = BB; @@ -283,7 +284,7 @@ llvm::SplitAllCriticalEdges(Function &F, BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt, DominatorTree *DT, LoopInfo *LI) { BasicBlock::iterator SplitIt = SplitPt; - while (isa(SplitIt) || isa(SplitIt)) + while (isa(SplitIt) || SplitIt->isEHPad()) ++SplitIt; BasicBlock *New = Old->splitBasicBlock(SplitIt, Old->getName()+".split"); @@ -474,6 +475,10 @@ BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB, ArrayRef Preds, const char *Suffix, DominatorTree *DT, LoopInfo *LI, bool PreserveLCSSA) { + // Do not attempt to split that which cannot be split. + if (!BB->canSplitPredecessors()) + return nullptr; + // For the landingpads we need to act a bit differently. // Delegate this work to the SplitLandingPadPredecessors. if (BB->isLandingPad()) { -- cgit v1.2.3