CodeGen: ensure that the runtime calling convention matches

Incorrect specification of the calling convention results in UB which can cause
the code path to be eliminated.  Simplify the existing code by using the
RuntimeCall constructor in `CodeGenFunction`.

llvm-svn: 284154

clang/lib/CodeGen/CGObjCRuntime.cpp

@@ -150,18 +150,16 @@ namespace {
   };
 
   struct CallObjCEndCatch final : EHScopeStack::Cleanup {
-    CallObjCEndCatch(bool MightThrow, llvm::Value *Fn) :
-      MightThrow(MightThrow), Fn(Fn) {}
+    CallObjCEndCatch(bool MightThrow, llvm::Value *Fn)
+        : MightThrow(MightThrow), Fn(Fn) {}
     bool MightThrow;
     llvm::Value *Fn;
 
     void Emit(CodeGenFunction &CGF, Flags flags) override {
-      if (!MightThrow) {
-        CGF.Builder.CreateCall(Fn)->setDoesNotThrow();
-        return;
-      }
-
-      CGF.EmitRuntimeCallOrInvoke(Fn);
+      if (MightThrow)
+        CGF.EmitRuntimeCallOrInvoke(Fn);
+      else
+        CGF.EmitNounwindRuntimeCall(Fn);
     }
   };
 }
@@ -230,10 +228,8 @@ void CGObjCRuntime::EmitTryCatchStmt(CodeGenFunction &CGF,
 
     // Enter the catch.
     llvm::Value *Exn = RawExn;
-    if (beginCatchFn) {
-      Exn = CGF.Builder.CreateCall(beginCatchFn, RawExn, "exn.adjusted");
-      cast<llvm::CallInst>(Exn)->setDoesNotThrow();
-    }
+    if (beginCatchFn)
+      Exn = CGF.EmitNounwindRuntimeCall(beginCatchFn, RawExn, "exn.adjusted");
 
     CodeGenFunction::LexicalScope cleanups(CGF, Handler.Body->getSourceRange());
 

clang/test/CodeGenObjC/runtime-abi-match.m

@@ -0,0 +1,24 @@
+// RUN: %clang -target armv7-windows -fobjc-runtime=ios -O1 -fexceptions -S -emit-llvm %s -o - | FileCheck %s
+
+void (*f)(id);
+void (*g)(void);
+void h(void);
+
+@interface NSNumber
++ (NSNumber *)numberWithInt:(int)i;
+@end
+
+void i(void) {
+  @try {
+    @throw(@1);
+  } @catch (id i) {
+    (*f)(i);
+    (*g)();
+  }
+}
+
+// CHECK: call arm_aapcs_vfpcc i8* @objc_begin_catch
+// CHECK: call arm_aapcs_vfpcc void @objc_end_catch
+// CHECK-NOT: call i8* @objc_begin_catch
+// CHECK-NOT: call void @objc_end_catch
+