Handle non-JSObject heap objects using slow-path IC stub guarded by the map.

src/objects-inl.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 533 matching lines @@
 
 bool Object::IsJSReceiver() {
   STATIC_ASSERT(LAST_JS_RECEIVER_TYPE == LAST_TYPE);
   return IsHeapObject() &&
       HeapObject::cast(this)->map()->instance_type() >= FIRST_JS_RECEIVER_TYPE;
 }
 
 
 bool Object::IsJSObject() {
   STATIC_ASSERT(LAST_JS_OBJECT_TYPE == LAST_TYPE);
-  return IsHeapObject() &&
-      HeapObject::cast(this)->map()->instance_type() >= FIRST_JS_OBJECT_TYPE;
+  return IsHeapObject() && HeapObject::cast(this)->map()->is_jsobject_map();
 }
 
 
 bool Object::IsJSProxy() {
   if (!Object::IsHeapObject()) return false;
   InstanceType type = HeapObject::cast(this)->map()->instance_type();
   return FIRST_JS_PROXY_TYPE <= type && type <= LAST_JS_PROXY_TYPE;
 }
 
 
@@ skipping 2935 matching lines @@
 
 void Map::set_non_instance_prototype(bool value) {
   if (value) {
     set_bit_field(bit_field() | (1 << kHasNonInstancePrototype));
   } else {
     set_bit_field(bit_field() & ~(1 << kHasNonInstancePrototype));
   }
 }
 
 
+bool Map::is_jsobject_map() {
+  return instance_type() >= FIRST_JS_OBJECT_TYPE;
+}
+
+
 bool Map::has_non_instance_prototype() {
   return ((1 << kHasNonInstancePrototype) & bit_field()) != 0;
 }
 
 
 void Map::set_function_with_prototype(bool value) {
   set_bit_field3(FunctionWithPrototype::update(bit_field3(), value));
 }
 
 
@@ skipping 2778 matching lines @@
 #undef WRITE_UINT32_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_