diff options
Diffstat (limited to 'llvm/lib/Transforms')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/LICM.cpp | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/llvm/lib/Transforms/Scalar/LICM.cpp b/llvm/lib/Transforms/Scalar/LICM.cpp index bd719ecbec1..225cfe28223 100644 --- a/llvm/lib/Transforms/Scalar/LICM.cpp +++ b/llvm/lib/Transforms/Scalar/LICM.cpp @@ -377,7 +377,7 @@ bool llvm::sinkRegion(DomTreeNode *N, AliasAnalysis *AA, LoopInfo *LI, // operands of the instruction are loop invariant. // if (isNotUsedInLoop(I, CurLoop, SafetyInfo) && - canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, SafetyInfo)) { + canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, SafetyInfo, ORE)) { ++II; Changed |= sink(I, LI, DT, CurLoop, CurAST, SafetyInfo, ORE); } @@ -432,7 +432,7 @@ bool llvm::hoistRegion(DomTreeNode *N, AliasAnalysis *AA, LoopInfo *LI, // is safe to hoist the instruction. // if (CurLoop->hasLoopInvariantOperands(&I) && - canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, SafetyInfo) && + canSinkOrHoistInst(I, AA, DT, CurLoop, CurAST, SafetyInfo, ORE) && isSafeToExecuteUnconditionally( I, DT, CurLoop, SafetyInfo, CurLoop->getLoopPreheader()->getTerminator())) @@ -481,7 +481,8 @@ void llvm::computeLoopSafetyInfo(LoopSafetyInfo *SafetyInfo, Loop *CurLoop) { bool llvm::canSinkOrHoistInst(Instruction &I, AAResults *AA, DominatorTree *DT, Loop *CurLoop, AliasSetTracker *CurAST, - LoopSafetyInfo *SafetyInfo) { + LoopSafetyInfo *SafetyInfo, + OptimizationRemarkEmitter *ORE) { // Loads have extra constraints we have to verify before we can hoist them. if (LoadInst *LI = dyn_cast<LoadInst>(&I)) { if (!LI->isUnordered()) @@ -502,7 +503,17 @@ bool llvm::canSinkOrHoistInst(Instruction &I, AAResults *AA, DominatorTree *DT, AAMDNodes AAInfo; LI->getAAMetadata(AAInfo); - return !pointerInvalidatedByLoop(LI->getOperand(0), Size, AAInfo, CurAST); + bool Invalidated = + pointerInvalidatedByLoop(LI->getOperand(0), Size, AAInfo, CurAST); + // Check loop-invariant address because this may also be a sinkable load + // whose address is not necessarily loop-invariant. + if (ORE && Invalidated && CurLoop->isLoopInvariant(LI->getPointerOperand())) + ORE->emit(OptimizationRemarkMissed( + DEBUG_TYPE, "LoadWithLoopInvariantAddressInvalidated", LI) + << "failed to move load with loop-invariant address " + "because the loop may invalidate its value"); + + return !Invalidated; } else if (CallInst *CI = dyn_cast<CallInst>(&I)) { // Don't sink or hoist dbg info; it's legal, but not useful. if (isa<DbgInfoIntrinsic>(I)) |
