[K/N] Fix crash on exporting cached suspend function

^KT-55736

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

@@ -1810,7 +1810,7 @@ private fun ObjCExportCodeGenerator.findImplementation(irClass: IrClass, method:
     val override = irClass.simpleFunctions().singleOrNull {
         method in it.getLowered().allOverriddenFunctions
     } ?: error("no implementation for ${method.render()}\nin ${irClass.fqNameWhenAvailable}")
-    return OverriddenFunctionInfo(override, method).getImplementation(context)
+    return OverriddenFunctionInfo(override.getLowered(), method).getImplementation(context)
 }
 
 private inline fun ObjCExportCodeGenerator.generateObjCToKotlinSyntheticGetter(

kotlin-native/backend.native/tests/objcexport/expectedLazy.h

@@ -1098,6 +1098,22 @@ __attribute__((swift_name("Kt54119Kt")))
 + (BOOL)callContainsEntryMap:(NSDictionary<id, id> *)map __attribute__((swift_name("callContainsEntry(map:)")));
 @end
 
+@interface KtKotlinSequenceScope (Kt55736Kt)
+
+/**
+ * @note This method converts instances of CancellationException to errors.
+ * Other uncaught Kotlin exceptions are fatal.
+*/
+- (void)fillWithCompletionHandler:(void (^)(NSError * _Nullable))completionHandler __attribute__((swift_name("fill(completionHandler:)")));
+@end
+
+__attribute__((objc_subclassing_restricted))
+__attribute__((swift_name("Kt55736Kt")))
+@interface KtKt55736Kt : KtBase
++ (id<KtKotlinKSuspendFunction1>)getFillFunction __attribute__((swift_name("getFillFunction()")));
++ (NSArray<KtInt *> *)callbackBlock:(id<KtKotlinSuspendFunction1>)block __attribute__((swift_name("callback(block:)")));
+@end
+
 __attribute__((objc_subclassing_restricted))
 __attribute__((swift_name("LibraryKt")))
 @interface KtLibraryKt : KtBase

kotlin-native/backend.native/tests/objcexport/expectedLazyLegacySuspendUnit.h

@@ -1033,6 +1033,22 @@ __attribute__((swift_name("Kt54119Kt")))
 + (BOOL)callContainsEntryMap:(NSDictionary<id, id> *)map __attribute__((swift_name("callContainsEntry(map:)")));
 @end
 
+@interface KtKotlinSequenceScope (Kt55736Kt)
+
+/**
+ * @note This method converts instances of CancellationException to errors.
+ * Other uncaught Kotlin exceptions are fatal.
+*/
+- (void)fillWithCompletionHandler:(void (^)(KtKotlinUnit * _Nullable, NSError * _Nullable))completionHandler __attribute__((swift_name("fill(completionHandler:)")));
+@end
+
+__attribute__((objc_subclassing_restricted))
+__attribute__((swift_name("Kt55736Kt")))
+@interface KtKt55736Kt : KtBase
++ (id<KtKotlinKSuspendFunction1>)getFillFunction __attribute__((swift_name("getFillFunction()")));
++ (NSArray<KtInt *> *)callbackBlock:(id<KtKotlinSuspendFunction1>)block __attribute__((swift_name("callback(block:)")));
+@end
+
 __attribute__((objc_subclassing_restricted))
 __attribute__((swift_name("LibraryKt")))
 @interface KtLibraryKt : KtBase

kotlin-native/backend.native/tests/objcexport/expectedLazyNoGenerics.h

@@ -1033,6 +1033,22 @@ __attribute__((swift_name("Kt54119Kt")))
 + (BOOL)callContainsEntryMap:(NSDictionary<id, id> *)map __attribute__((swift_name("callContainsEntry(map:)")));
 @end
 
+@interface KtKotlinSequenceScope (Kt55736Kt)
+
+/**
+ * @note This method converts instances of CancellationException to errors.
+ * Other uncaught Kotlin exceptions are fatal.
+*/
+- (void)fillWithCompletionHandler:(void (^)(NSError * _Nullable))completionHandler __attribute__((swift_name("fill(completionHandler:)")));
+@end
+
+__attribute__((objc_subclassing_restricted))
+__attribute__((swift_name("Kt55736Kt")))
+@interface KtKt55736Kt : KtBase
++ (id<KtKotlinKSuspendFunction1>)getFillFunction __attribute__((swift_name("getFillFunction()")));
++ (NSArray<KtInt *> *)callbackBlock:(id<KtKotlinSuspendFunction1>)block __attribute__((swift_name("callback(block:)")));
+@end
+
 __attribute__((objc_subclassing_restricted))
 __attribute__((swift_name("LibraryKt")))
 @interface KtLibraryKt : KtBase

kotlin-native/backend.native/tests/objcexport/kt55736.kt

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+import kotlin.sequences.*
+
+suspend fun SequenceScope<Int>.fill() {
+    yield(1)
+    yield(2)
+}
+
+fun getFillFunction() = SequenceScope<Int>::fill
+
+fun callback(block: suspend SequenceScope<Int>.() -> Unit) : List<Int> {
+    return sequence {
+        block()
+    }.toList()
+}

kotlin-native/backend.native/tests/objcexport/kt55736.swift

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+import Foundation
+import Kt
+
+private func testFill() throws {
+    let result = Kt55736Kt.callback(block: Kt55736Kt.getFillFunction())
+    try assertEquals(actual: result.count, expected: 2)
+    try assertEquals(actual: result[0], expected: 1)
+    try assertEquals(actual: result[1], expected: 2)
+}
+
+class Kt55736Tests : SimpleTestProvider {
+    override init() {
+        super.init()
+
+        test("testFill", testFill)
+    }
+}