blob: 8dbe1dce03eec1002e350284d27f3e821a0f914a [file] [log] [blame]
// Copyright 2019 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// JSReceiver corresponds to objects in the JS sense.
extern class JSReceiver extends HeapObject {
properties_or_hash: FixedArrayBase|PropertyArray|Smi;
type Constructor extends JSReceiver;
extern class JSObject extends JSReceiver {
// [elements]: The elements (properties with names that are integers).
// Elements can be in two general modes: fast and slow. Each mode
// corresponds to a set of object representations of elements that
// have something in common.
// In the fast mode elements is a FixedArray and so each element can be
// quickly accessed. The elements array can have one of several maps in this
// mode: fixed_array_map, fixed_double_array_map,
// sloppy_arguments_elements_map or fixed_cow_array_map (for copy-on-write
// arrays). In the latter case the elements array may be shared by a few
// objects and so before writing to any element the array must be copied. Use
// EnsureWritableFastElements in this case.
// In the slow mode the elements is either a NumberDictionary or a
// FixedArray parameter map for a (sloppy) arguments object.
elements: FixedArrayBase;
macro NewJSObject(implicit context: Context)(): JSObject {
const objectFunction: JSFunction = GetObjectFunction();
const map: Map = Cast<Map>(objectFunction.prototype_or_initial_map)
otherwise unreachable;
return AllocateJSObjectFromMap(map);
extern class JSCustomElementsObject extends JSObject {
extern class JSSpecialObject extends JSCustomElementsObject {
macro GetDerivedMap(implicit context: Context)(
target: JSFunction, newTarget: JSReceiver): Map {
try {
const constructor =
Cast<JSFunctionWithPrototypeSlot>(newTarget) otherwise SlowPath;
const map =
Cast<Map>(constructor.prototype_or_initial_map) otherwise SlowPath;
if (LoadConstructorOrBackPointer(map) != target) {
goto SlowPath;
return map;
} label SlowPath {
return runtime::GetDerivedMap(context, target, newTarget);
macro AllocateFastOrSlowJSObjectFromMap(implicit context: Context)(map: Map):
JSObject {
let properties: EmptyFixedArray|NameDictionary = kEmptyFixedArray;
if (IsDictionaryMap(map)) {
properties = AllocateNameDictionary(kNameDictionaryInitialCapacity);
return AllocateJSObjectFromMap(
map, properties, kEmptyFixedArray, AllocationFlag::kNone,
extern class JSGlobalProxy extends JSSpecialObject {
// [native_context]: the owner native context of this global proxy object.
// It is null value if this object is not used by any context.
native_context: Object;
extern class JSGlobalObject extends JSSpecialObject {
native_context: NativeContext;
global_proxy: JSGlobalProxy;
extern class JSPrimitiveWrapper extends JSCustomElementsObject {
value: JSAny;
extern class JSMessageObject extends JSObject {
// Tagged fields.
message_type: Smi;
arguments: Object;
script: Script;
stack_frames: Object;
shared_info: SharedFunctionInfo|Undefined;
// Raw data fields.
// TODO(ishell): store as int32 instead of Smi.
bytecode_offset: Smi;
start_position: Smi;
end_position: Smi;
error_level: Smi;
extern class JSDate extends JSObject {
// If one component is NaN, all of them are, indicating a NaN time value.
// The time value.
value: NumberOrUndefined;
// Cached values:
year: Undefined|Smi|NaN;
month: Undefined|Smi|NaN;
day: Undefined|Smi|NaN;
weekday: Undefined|Smi|NaN;
hour: Undefined|Smi|NaN;
min: Undefined|Smi|NaN;
sec: Undefined|Smi|NaN;
// Sample of the date cache stamp at the moment when chached fields were
// cached.
cache_stamp: Undefined|Smi|NaN;
extern class JSAsyncFromSyncIterator extends JSObject {
sync_iterator: JSReceiver;
// The "next" method is loaded during GetIterator, and is not reloaded for
// subsequent "next" invocations.
next: Object;
extern class JSStringIterator extends JSObject {
// The [[IteratedString]] slot.
string: String;
// The [[StringIteratorNextIndex]] slot.
index: Smi;
extern macro AllocateJSObjectFromMap(Map): JSObject;
extern macro AllocateJSObjectFromMap(
Map, NameDictionary | EmptyFixedArray | PropertyArray): JSObject;
extern macro AllocateJSObjectFromMap(
Map, NameDictionary | EmptyFixedArray | PropertyArray, FixedArray,
constexpr AllocationFlag, constexpr SlackTrackingMode): JSObject;