[builtins] implement Array.prototype.includes in TurboFan

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 0f7660a71a295e820c9073ef0c6fff457ac930bc..cfd744cbd9847d83cf6794404784aea1b2608d17 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -1134,6 +1134,20 @@ MUST_USE_RESULT MaybeHandle<FixedArray> JSReceiver::OwnPropertyKeys(
                                  GetKeysConversion::kConvertToString);
 }
 
+bool JSObject::PrototypeHasNoElements(Isolate* isolate, JSObject* object) {

[Camillo Bruni, 2016/07/21 08:01:55]

indeed makes more sense here :)

+  DisallowHeapAllocation no_gc;
+  HeapObject* prototype = HeapObject::cast(object->map()->prototype());
+  HeapObject* null = isolate->heap()->null_value();
+  HeapObject* empty = isolate->heap()->empty_fixed_array();
+  while (prototype != null) {
+    Map* map = prototype->map();
+    if (map->instance_type() <= LAST_CUSTOM_ELEMENTS_RECEIVER) return false;
+    if (JSObject::cast(prototype)->elements() != empty) return false;
+    prototype = HeapObject::cast(map->prototype());
+  }
+  return true;
+}
+
 #define FIELD_ADDR(p, offset) \
   (reinterpret_cast<byte*>(p) + offset - kHeapObjectTag)