Index: llvm/lib/Analysis/ValueTracking.cpp =================================================================== --- llvm/lib/Analysis/ValueTracking.cpp +++ llvm/lib/Analysis/ValueTracking.cpp @@ -4221,22 +4221,9 @@ } bool llvm::isGuaranteedToTransferExecutionToSuccessor(const Instruction *I) { - // A memory operation returns normally if it isn't volatile. A volatile - // operation is allowed to trap. - // - // An atomic operation isn't guaranteed to return in a reasonable amount of - // time because it's possible for another thread to interfere with it for an + // Note: An atomic operation isn't guaranteed to return in a reasonable amount + // of time because it's possible for another thread to interfere with it for an // arbitrary length of time, but programs aren't allowed to rely on that. - if (const LoadInst *LI = dyn_cast(I)) - return !LI->isVolatile(); - if (const StoreInst *SI = dyn_cast(I)) - return !SI->isVolatile(); - if (const AtomicCmpXchgInst *CXI = dyn_cast(I)) - return !CXI->isVolatile(); - if (const AtomicRMWInst *RMWI = dyn_cast(I)) - return !RMWI->isVolatile(); - if (const MemIntrinsic *MII = dyn_cast(I)) - return !MII->isVolatile(); // If there is no successor, then execution can't transfer to it. if (const auto *CRI = dyn_cast(I)) Index: llvm/test/Transforms/FunctionAttrs/nonnull.ll =================================================================== --- llvm/test/Transforms/FunctionAttrs/nonnull.ll +++ llvm/test/Transforms/FunctionAttrs/nonnull.ll @@ -347,10 +347,12 @@ } ; The callsite must execute in order for the attribute to transfer to the parent. -; The volatile load might trap, so there's no guarantee that we'll ever get to the call. +; The volatile load can't trap, so we can guarantee that we'll get to the call. define i8 @parent6(i8* %a, i8* %b) { -; BOTH-LABEL: @parent6(i8* %a, i8* %b) +; FNATTR-LABEL: @parent6(i8* nonnull %a, i8* %b) +; FIXME: missing "nonnull" +; ATTRIBUTOR-LABEL: @parent6(i8* %a, i8* %b) ; BOTH-NEXT: [[C:%.*]] = load volatile i8, i8* %b ; FNATTR-NEXT: call void @use1nonnull(i8* %a) ; ATTRIBUTOR-NEXT: call void @use1nonnull(i8* nonnull %a)