fix rdar://7590304, a miscompilation of objc apps on arm. The caller
of objc message send was getting marked arm_apcscc, but the prototype
isn't. This is fine at runtime because objcmsgsend is implemented in
assembly. Only turn a mismatched caller and callee into 'unreachable'
if the callee is a definition.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94986 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/InstCombine/InstCombineCalls.cpp b/lib/Transforms/InstCombine/InstCombineCalls.cpp
index 9c420c8..5de846e 100644
--- a/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -692,10 +692,14 @@
Value *Callee = CS.getCalledValue();
if (Function *CalleeF = dyn_cast<Function>(Callee))
- if (CalleeF->getCallingConv() != CS.getCallingConv()) {
+ // If the call and callee calling conventions don't match, this call must
+ // be unreachable, as the call is undefined.
+ if (CalleeF->getCallingConv() != CS.getCallingConv() &&
+ // Only do this for calls to a function with a body. A prototype may
+ // not actually end up matching the implementation's calling conv for a
+ // variety of reasons (e.g. it may be written in assembly).
+ !CalleeF->isDeclaration()) {
Instruction *OldCall = CS.getInstruction();
- // If the call and callee calling conventions don't match, this call must
- // be unreachable, as the call is undefined.
new StoreInst(ConstantInt::getTrue(Callee->getContext()),
UndefValue::get(Type::getInt1PtrTy(Callee->getContext())),
OldCall);