ObjCExport: don't generate redundant exception handler for objc_release

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/CodeGenerator.kt

@@ -661,6 +661,12 @@ internal abstract class FunctionGenerationContext(
         }.let {} // Force exhaustive.
     }
 
+    fun switchThreadStateIfExperimentalMM(state: ThreadState) {
+        if (context.memoryModel == MemoryModel.EXPERIMENTAL) {
+            switchThreadState(state)
+        }
+    }
+
     fun memset(pointer: LLVMValueRef, value: Byte, size: Int, isVolatile: Boolean = false) =
             call(context.llvm.memsetFunction,
                     listOf(pointer,

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/objcexport/ObjCExportCodeGenerator.kt

@@ -86,6 +86,13 @@ internal class ObjCExportFunctionGenerationContext(
         rawRet(result)
     }
 
+    fun objcReleaseFromRunnableThreadState(objCReference: LLVMValueRef) {
+        switchThreadStateIfExperimentalMM(ThreadState.Native)
+        // It is nounwind, so no exception handler is required.
+        call(objCExportCodegen.objcRelease, listOf(objCReference), exceptionHandler = ExceptionHandler.None)
+        switchThreadStateIfExperimentalMM(ThreadState.Runnable)
+    }
+
     override fun processReturns() {
         // Do nothing.
     }
@@ -1041,7 +1048,7 @@ private fun ObjCExportCodeGenerator.generateObjCImp(
                 is MethodBridge.ReturnValue.WithError.ZeroForError -> {
                     if (returnType.successBridge == MethodBridge.ReturnValue.Instance.InitResult) {
                         // Release init receiver, as required by convention.
-                        callFromBridge(objcRelease, listOf(param(0)), toNative = true)
+                        objcReleaseFromRunnableThreadState(param(0))
                     }
                     Zero(returnType.toLlvmRetType(context).llvmType).llvm
                 }