1/*
2 * Copyright (C) 2008-2019 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include "JSCast.h"
29#include "JSObject.h"
30#include "Structure.h"
31#include <wtf/StdLibExtras.h>
32#include <wtf/UniqueArray.h>
33
34namespace JSC {
35
36class LLIntOffsetsExtractor;
37class Structure;
38
39class StructureChain final : public JSCell {
40 friend class JIT;
41
42public:
43 using Base = JSCell;
44 static constexpr unsigned StructureFlags = Base::StructureFlags | StructureIsImmortal;
45
46 static StructureChain* create(VM&, JSObject*);
47 WriteBarrier<Structure>* head() { return m_vector.get(); }
48 static void visitChildren(JSCell*, SlotVisitor&);
49
50 static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
51 {
52 return Structure::create(vm, globalObject, prototype, TypeInfo(CellType, StructureFlags), info());
53 }
54
55 DECLARE_INFO;
56
57private:
58 friend class LLIntOffsetsExtractor;
59
60 void finishCreation(VM&, JSObject* head);
61
62 StructureChain(VM&, Structure*, WriteBarrier<Structure>*);
63 AuxiliaryBarrier<WriteBarrier<Structure>*> m_vector;
64};
65
66} // namespace JSC
67