Use runtime bitcode to get size of primitive types

As an alternative to explicitly setting type size in konan.properties or
backend code we can "ask" LLVM about it.
Unfortunately, there is no Clang/LLVM API for it,
so we use a trivial workaround:
Create dumb function in runtime code, and then extract info about
return type size using LLVM.

kotlin-native/runtime/src/main/cpp/ObjCExport.h

@@ -39,6 +39,9 @@ extern "C" OBJ_GETTER(Kotlin_ObjCExport_refFromObjC, id obj);
 extern "C" id Kotlin_Interop_CreateNSStringFromKString(KRef str);
 extern "C" OBJ_GETTER(Kotlin_Interop_CreateKStringFromNSString, NSString* str);
 
+/// Utility function that is used to determine NSInteger size in compile time.
+extern "C" NSInteger Kotlin_ObjCExport_NSIntegerTypeProvider();
+
 #endif // KONAN_OBJC_INTEROP
 
 #endif // RUNTIME_OBJCEXPORT_H

kotlin-native/runtime/src/main/cpp/ObjCExport.mm

@@ -1090,6 +1090,10 @@ extern "C" void Kotlin_ObjCExport_AbstractMethodCalled(id self, SEL selector) {
         class_getName(object_getClass(self)), sel_getName(selector)];
 }
 
+extern "C" NSInteger Kotlin_ObjCExport_NSIntegerTypeProvider() {
+    return 0;
+}
+
 #else
 
 extern "C" ALWAYS_INLINE void* Kotlin_Interop_refToObjC(ObjHeader* obj) {

kotlin-native/runtime/src/main/cpp/Types.cpp

@@ -108,4 +108,8 @@ KVector4f Kotlin_Vector4i32_of(KInt f0, KInt f1, KInt f2, KInt f3) {
 	return (KVector4f)v4i;
 }
 
+long Kotlin_longTypeProvider() {
+    return 0;
+}
+
 }  // extern "C"

kotlin-native/runtime/src/main/cpp/Types.h

@@ -124,6 +124,9 @@ void CheckCast(const ObjHeader* obj, const TypeInfo* type_info);
 KBoolean IsArray(KConstRef obj) RUNTIME_PURE;
 bool IsSubInterface(const TypeInfo* thiz, const TypeInfo* other) RUNTIME_PURE;
 
+/// Utility function that is used to determine long type size in compile time.
+long Kotlin_longTypeProvider();
+
 #ifdef __cplusplus
 }
 #endif