diff options
Diffstat (limited to 'llvm/lib/Transforms/Scalar/GVN.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/GVN.cpp | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/llvm/lib/Transforms/Scalar/GVN.cpp b/llvm/lib/Transforms/Scalar/GVN.cpp index 7595ae05787..a02f32f5643 100644 --- a/llvm/lib/Transforms/Scalar/GVN.cpp +++ b/llvm/lib/Transforms/Scalar/GVN.cpp @@ -1131,6 +1131,14 @@ bool GVN::PerformLoadPRE(LoadInst *LI, AvailValInBlkVect &ValuesPerBlock, return false; } + // FIXME: Can we support the fallthrough edge? + if (isa<CallBrInst>(Pred->getTerminator())) { + LLVM_DEBUG( + dbgs() << "COULD NOT PRE LOAD BECAUSE OF CALLBR CRITICAL EDGE '" + << Pred->getName() << "': " << *LI << '\n'); + return false; + } + if (LoadBB->isEHPad()) { LLVM_DEBUG( dbgs() << "COULD NOT PRE LOAD BECAUSE OF AN EH PAD CRITICAL EDGE '" @@ -2167,8 +2175,8 @@ bool GVN::performScalarPRE(Instruction *CurInst) { return false; // We don't currently value number ANY inline asm calls. - if (CallInst *CallI = dyn_cast<CallInst>(CurInst)) - if (CallI->isInlineAsm()) + if (auto *CallB = dyn_cast<CallBase>(CurInst)) + if (CallB->isInlineAsm()) return false; uint32_t ValNo = VN.lookup(CurInst); @@ -2251,6 +2259,11 @@ bool GVN::performScalarPRE(Instruction *CurInst) { if (isa<IndirectBrInst>(PREPred->getTerminator())) return false; + // Don't do PRE across callbr. + // FIXME: Can we do this across the fallthrough edge? + if (isa<CallBrInst>(PREPred->getTerminator())) + return false; + // We can't do PRE safely on a critical edge, so instead we schedule // the edge to be split and perform the PRE the next time we iterate // on the function. |
