1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef vm_ObjectFlags_h
#define vm_ObjectFlags_h
#include <stdint.h>
#include "util/EnumFlags.h" // js::EnumFlags
namespace js {
// Flags set on the Shape which describe the referring object. Once set these
// cannot be unset (except during object densification of sparse indexes), and
// are transferred from shape to shape as the object's last property changes.
//
// If you add a new flag here, please add appropriate code to JSObject::dump to
// dump it as part of the object representation.
enum class ObjectFlag : uint16_t {
IsUsedAsPrototype = 1 << 0,
NotExtensible = 1 << 1,
Indexed = 1 << 2,
HasInterestingSymbol = 1 << 3,
// If set, the shape's property map may contain an enumerable property. This
// only accounts for (own) shape properties: if the flag is not set, the
// object may still have (enumerable) dense elements, typed array elements, or
// a JSClass enumeration hook.
HasEnumerable = 1 << 4,
FrozenElements = 1 << 5, // See ObjectElements::FROZEN comment.
// If set, the shape teleporting optimization can no longer be used for
// accessing properties on this object.
// See: JSObject::hasInvalidatedTeleporting, ProtoChainSupportsTeleporting.
InvalidatedTeleporting = 1 << 6,
ImmutablePrototype = 1 << 7,
// See JSObject::isQualifiedVarObj().
QualifiedVarObj = 1 << 8,
// If set, the object may have a non-writable property or an accessor
// property.
//
// * This is only set for PlainObjects because we only need it for these
// objects and setting it for other objects confuses insertInitialShape.
//
// * This flag does not account for properties named "__proto__". This is
// because |Object.prototype| has a "__proto__" accessor property and we
// don't want to include it because it would result in the flag being set on
// most proto chains. Code using this flag must check for "__proto__"
// property names separately.
HasNonWritableOrAccessorPropExclProto = 1 << 9,
// If set, the object either mutated or deleted an accessor property. This is
// used to invalidate IC/Warp code specializing on specific getter/setter
// objects. See also the SMDOC comment in vm/GetterSetter.h.
HadGetterSetterChange = 1 << 10,
// If set, use the watchtower testing mechanism to log changes to this object.
UseWatchtowerTestingLog = 1 << 11,
// If set, access to existing properties of this global object can be guarded
// based on a per-global counter that is incremented when the global object
// has its properties reordered/shadowed, instead of a shape guard.
GenerationCountedGlobal = 1 << 12,
// If set, we need to verify the result of a proxy get/set trap.
//
// The [[Get]] and [[Set]] traps for proxy objects enforce certain invariants
// for non-configurable, non-writable data properties and non-configurable
// accessors. If the invariants are not maintained, we must throw a type
// error. If this flag is not set, and this is a NativeObject, *and* the
// class does not have a resolve hook, then this object does not have any
// such properties, and we can skip the slow check.
//
// See
// https://tc39.es/ecma262/#sec-proxy-object-internal-methods-and-internal-slots
NeedsProxyGetSetResultValidation = 1 << 13,
// There exists a property on this object which has fuse semantics associated
// with it, and thus we must trap on changes to said property.
HasFuseProperty = 1 << 14,
};
using ObjectFlags = EnumFlags<ObjectFlag>;
} // namespace js
#endif /* vm_ObjectFlags_h */
|
