diff options
Diffstat (limited to 'contrib/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp')
| -rw-r--r-- | contrib/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/contrib/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp b/contrib/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp index a6907b5..136d54a 100644 --- a/contrib/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp +++ b/contrib/llvm/lib/Transforms/ObjCARC/ObjCARCOpts.cpp @@ -53,6 +53,11 @@ using namespace llvm::objcarc; /// \brief This is similar to GetRCIdentityRoot but it stops as soon /// as it finds a value with multiple uses. static const Value *FindSingleUseIdentifiedObject(const Value *Arg) { + // ConstantData (like ConstantPointerNull and UndefValue) is used across + // modules. It's never a single-use value. + if (isa<ConstantData>(Arg)) + return nullptr; + if (Arg->hasOneUse()) { if (const BitCastInst *BC = dyn_cast<BitCastInst>(Arg)) return FindSingleUseIdentifiedObject(BC->getOperand(0)); @@ -644,6 +649,12 @@ void ObjCARCOpt::OptimizeAutoreleaseRVCall(Function &F, ARCInstKind &Class) { // Check for a return of the pointer value. const Value *Ptr = GetArgRCIdentityRoot(AutoreleaseRV); + + // If the argument is ConstantPointerNull or UndefValue, its other users + // aren't actually interesting to look at. + if (isa<ConstantData>(Ptr)) + return; + SmallVector<const Value *, 2> Users; Users.push_back(Ptr); do { @@ -2075,12 +2086,11 @@ void ObjCARCOpt::OptimizeReturns(Function &F) { SmallPtrSet<const BasicBlock *, 4> Visited; for (BasicBlock &BB: F) { ReturnInst *Ret = dyn_cast<ReturnInst>(&BB.back()); - - DEBUG(dbgs() << "Visiting: " << *Ret << "\n"); - if (!Ret) continue; + DEBUG(dbgs() << "Visiting: " << *Ret << "\n"); + const Value *Arg = GetRCIdentityRoot(Ret->getOperand(0)); // Look for an ``autorelease'' instruction that is a predecessor of Ret and |
