r360474 - [CodeGen][ObjC] Emit invoke instead of call to call `objc_release` when

[Akira Hatanaka via cfe-commits]

Author: ahatanak
Date: Fri May 10 14:54:16 2019
New Revision: 360474

URL: http://llvm.org/viewvc/llvm-project?rev=360474&view=rev
Log:
[CodeGen][ObjC] Emit invoke instead of call to call `objc_release` when
necessary.

Prior to r349952, clang used to call objc_msgSend when sending a release
messages, emitting an invoke instruction instead of a call instruction
when it was necessary to catch an exception. That changed in r349952
because runtime function objc_release is called as a nounwind function,
which broke programs that were overriding the dealloc method and
throwing an exception from it. This patch restores the behavior prior to
r349952.

rdar://problem/50253394

Differential Revision: https://reviews.llvm.org/D61803

Modified:
    cfe/trunk/lib/CodeGen/CGObjC.cpp
    cfe/trunk/test/CodeGenObjC/convert-messages-to-runtime-calls.m

Modified: cfe/trunk/lib/CodeGen/CGObjC.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGObjC.cpp?rev=360474&r1=360473&r2=360474&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGObjC.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGObjC.cpp Fri May 10 14:54:16 2019
@@ -2631,7 +2631,7 @@ void CodeGenFunction::EmitObjCRelease(ll
   value = Builder.CreateBitCast(value, Int8PtrTy);
 
   // Call objc_release.
-  llvm::CallInst *call = EmitNounwindRuntimeCall(fn, value);
+  llvm::CallBase *call = EmitCallOrInvoke(fn, value);
 
   if (precise == ARCImpreciseLifetime) {
     call->setMetadata("clang.imprecise_release",

Modified: cfe/trunk/test/CodeGenObjC/convert-messages-to-runtime-calls.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenObjC/convert-messages-to-runtime-calls.m?rev=360474&r1=360473&r2=360474&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenObjC/convert-messages-to-runtime-calls.m (original)
+++ cfe/trunk/test/CodeGenObjC/convert-messages-to-runtime-calls.m Fri May 10 14:54:16 2019
@@ -175,3 +175,14 @@ float test_cannot_message_return_float(C
 
 @end
 
+ at class Ety;
+
+// CHECK-LABEL: define {{.*}}void @testException
+void testException(NSObject *a) {
+  // MSGS: {{invoke.*@objc_msgSend}}
+  // CALLS: invoke{{.*}}void @objc_release(i8* %
+  @try {
+    [a release];
+  } @catch (Ety *e) {
+  }
+}