diff options
Diffstat (limited to 'llvm/lib/Analysis/LoopAccessAnalysis.cpp')
| -rw-r--r-- | llvm/lib/Analysis/LoopAccessAnalysis.cpp | 32 |
1 files changed, 22 insertions, 10 deletions
diff --git a/llvm/lib/Analysis/LoopAccessAnalysis.cpp b/llvm/lib/Analysis/LoopAccessAnalysis.cpp index 87fae92977cd..7adb25d0e5e0 100644 --- a/llvm/lib/Analysis/LoopAccessAnalysis.cpp +++ b/llvm/lib/Analysis/LoopAccessAnalysis.cpp @@ -233,14 +233,25 @@ static bool evaluatePtrAddRecAtMaxBTCWillNotWrap( const SCEV *DerefBytesSCEV = SE.getConstant(WiderTy, DerefBytes); // Check if we have a suitable dereferencable assumption we can use. - if (!StartPtrV->canBeFreed()) { - RetainedKnowledge DerefRK = getKnowledgeValidInContext( - StartPtrV, {Attribute::Dereferenceable}, *AC, - L->getLoopPredecessor()->getTerminator(), DT); - if (DerefRK) { - DerefBytesSCEV = - SE.getUMaxExpr(DerefBytesSCEV, SE.getSCEV(DerefRK.IRArgValue)); - } + Instruction *CtxI = &*L->getHeader()->getFirstNonPHIIt(); + if (BasicBlock *LoopPred = L->getLoopPredecessor()) { + if (isa<BranchInst>(LoopPred->getTerminator())) + CtxI = LoopPred->getTerminator(); + } + RetainedKnowledge DerefRK; + getKnowledgeForValue(StartPtrV, {Attribute::Dereferenceable}, *AC, + [&](RetainedKnowledge RK, Instruction *Assume, auto) { + if (!isValidAssumeForContext(Assume, CtxI, DT)) + return false; + if (StartPtrV->canBeFreed() && + !willNotFreeBetween(Assume, CtxI)) + return false; + DerefRK = std::max(DerefRK, RK); + return true; + }); + if (DerefRK) { + DerefBytesSCEV = + SE.getUMaxExpr(DerefBytesSCEV, SE.getSCEV(DerefRK.IRArgValue)); } if (DerefBytesSCEV->isZero()) @@ -2856,8 +2867,9 @@ void LoopAccessInfo::emitUnsafeDependenceRemark() { } } -bool LoopAccessInfo::blockNeedsPredication(BasicBlock *BB, Loop *TheLoop, - DominatorTree *DT) { +bool LoopAccessInfo::blockNeedsPredication(const BasicBlock *BB, + const Loop *TheLoop, + const DominatorTree *DT) { assert(TheLoop->contains(BB) && "Unknown block used"); // Blocks that do not dominate the latch need predication. |