diff options
| -rw-r--r-- | lib/Transforms/Scalar/InstructionCombining.cpp | 10 | ||||
| -rw-r--r-- | test/Transforms/InstCombine/nothrow.ll | 8 |
2 files changed, 18 insertions, 0 deletions
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index c76403e039..527ed43010 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -9578,6 +9578,16 @@ Instruction *InstCombiner::SimplifyMemSet(MemSetInst *MI) { /// the heavy lifting. /// Instruction *InstCombiner::visitCallInst(CallInst &CI) { + // If the caller function is nounwind, mark the call as nounwind, even if the + // callee isn't. + if (CI.getParent()->getParent()->doesNotThrow() && + !CI.doesNotThrow()) { + CI.setDoesNotThrow(); + return &CI; + } + + + IntrinsicInst *II = dyn_cast<IntrinsicInst>(&CI); if (!II) return visitCallSite(&CI); diff --git a/test/Transforms/InstCombine/nothrow.ll b/test/Transforms/InstCombine/nothrow.ll new file mode 100644 index 0000000000..fbf162a1db --- /dev/null +++ b/test/Transforms/InstCombine/nothrow.ll @@ -0,0 +1,8 @@ +; RUN: llvm-as < %s | opt -instcombine | llvm-dis | not grep call +; rdar://6880732 +declare double @t1(i32) readonly + +define void @t2() nounwind { + call double @t1(i32 42) ;; dead call even though callee is not nothrow. + ret void +} |