diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/ObjCARC.cpp | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/Scalar/ObjCARC.cpp b/llvm/lib/Transforms/Scalar/ObjCARC.cpp index fea03b5f5b5..9654b1ecd30 100644 --- a/llvm/lib/Transforms/Scalar/ObjCARC.cpp +++ b/llvm/lib/Transforms/Scalar/ObjCARC.cpp @@ -515,6 +515,10 @@ static bool IsObjCIdentifiedObject(const Value *V) { const Value *Pointer = StripPointerCastsAndObjCCalls(LI->getPointerOperand()); if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(Pointer)) { + // A constant pointer can't be pointing to an object on the heap. It may + // be reference-counted, but it won't be deleted. + if (GV->isConstant()) + return true; StringRef Name = GV->getName(); // These special variables are known to hold values which are not // reference-counted pointers. @@ -2744,6 +2748,15 @@ ObjCARCOpt::PerformCodePlacement(DenseMap<const BasicBlock *, BBState> // regardless of what possible decrements or uses lie between them. bool KnownSafe = isa<Constant>(Arg) || isa<AllocaInst>(Arg); + // A constant pointer can't be pointing to an object on the heap. It may + // be reference-counted, but it won't be deleted. + if (const LoadInst *LI = dyn_cast<LoadInst>(Arg)) + if (const GlobalVariable *GV = + dyn_cast<GlobalVariable>( + StripPointerCastsAndObjCCalls(LI->getPointerOperand()))) + if (GV->isConstant()) + KnownSafe = true; + // If a pair happens in a region where it is known that the reference count // is already incremented, we can similarly ignore possible decrements. bool KnownSafeTD = true, KnownSafeBU = true; |
