diff options
Diffstat (limited to 'llvm/lib/Transforms/Scalar/JumpThreading.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/JumpThreading.cpp | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/llvm/lib/Transforms/Scalar/JumpThreading.cpp b/llvm/lib/Transforms/Scalar/JumpThreading.cpp index 29c707799bd..4e02fc7da20 100644 --- a/llvm/lib/Transforms/Scalar/JumpThreading.cpp +++ b/llvm/lib/Transforms/Scalar/JumpThreading.cpp @@ -752,6 +752,8 @@ bool JumpThreadingPass::ComputeValueKnownInPredecessors( CmpInst::Predicate Pred = Cmp->getPredicate(); PHINode *PN = dyn_cast<PHINode>(CmpLHS); + if (!PN) + PN = dyn_cast<PHINode>(CmpRHS); if (PN && PN->getParent() == BB) { const DataLayout &DL = PN->getModule()->getDataLayout(); // We can do this simplification if any comparisons fold to true or false. @@ -762,14 +764,24 @@ bool JumpThreadingPass::ComputeValueKnownInPredecessors( LVI->enableDT(); for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { BasicBlock *PredBB = PN->getIncomingBlock(i); - Value *LHS = PN->getIncomingValue(i); - Value *RHS = CmpRHS->DoPHITranslation(BB, PredBB); - + Value *LHS, *RHS; + if (PN == CmpLHS) { + LHS = PN->getIncomingValue(i); + RHS = CmpRHS->DoPHITranslation(BB, PredBB); + } else { + LHS = CmpLHS->DoPHITranslation(BB, PredBB); + RHS = PN->getIncomingValue(i); + } Value *Res = SimplifyCmpInst(Pred, LHS, RHS, {DL}); if (!Res) { if (!isa<Constant>(RHS)) continue; + // getPredicateOnEdge call will make no sense if LHS is defined in BB. + auto LHSInst = dyn_cast<Instruction>(LHS); + if (LHSInst && LHSInst->getParent() == BB) + continue; + LazyValueInfo::Tristate ResT = LVI->getPredicateOnEdge(Pred, LHS, cast<Constant>(RHS), PredBB, BB, |
