1/*
2 * Copyright (C) 2016 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. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include "LazyProperty.h"
29#include "Structure.h"
30
31namespace JSC {
32
33class JSGlobalObject;
34class VM;
35
36class LazyClassStructure {
37 typedef LazyProperty<JSGlobalObject, Structure>::Initializer StructureInitializer;
38
39public:
40 struct Initializer {
41 Initializer(VM&, JSGlobalObject*, LazyClassStructure&, const StructureInitializer&);
42
43 // This should be called first or not at all.
44 void setPrototype(JSObject* prototype);
45
46 // If this is called after setPrototype() then it just sets the structure. If this is
47 // called first then it sets the prototype by extracting it from the structure.
48 void setStructure(Structure*);
49
50 // Call this last. It's expected that the constructor is initialized to point to the
51 // prototype already. This will automatically set prototype.constructor=constructor.
52 // This will also stuff the constructor into the global object at the given property.
53 // Note that the variant that does not take a property name attempts to deduce it by
54 // casting constructor to either JSFunction or InternalFunction. Also, you can pass
55 // nullptr for the property name, in which case we don't assign the property to the
56 // global object.
57 void setConstructor(PropertyName, JSObject* constructor);
58 void setConstructor(JSObject* constructor);
59
60 VM& vm;
61 JSGlobalObject* global;
62 LazyClassStructure& classStructure;
63 const StructureInitializer& structureInit;
64
65 // It's expected that you set these using the set methods above.
66 JSObject* prototype { nullptr };
67 Structure* structure { nullptr };
68 JSObject* constructor { nullptr };
69 };
70
71 LazyClassStructure()
72 {
73 }
74
75 template<typename Callback>
76 void initLater(const Callback&);
77
78 Structure* get(const JSGlobalObject* global) const
79 {
80 ASSERT(!isCompilationThread());
81 return m_structure.get(global);
82 }
83
84 JSObject* prototype(const JSGlobalObject* global) const
85 {
86 ASSERT(!isCompilationThread());
87 return get(global)->storedPrototypeObject();
88 }
89
90 // Almost as an afterthought, we also support getting the original constructor. This turns
91 // out to be important for ES6 support.
92 JSObject* constructor(const JSGlobalObject* global) const
93 {
94 ASSERT(!isCompilationThread());
95 m_structure.get(global);
96 return m_constructor.get();
97 }
98
99 Structure* getConcurrently() const
100 {
101 return m_structure.getConcurrently();
102 }
103
104 JSObject* constructorConcurrently() const
105 {
106 return m_constructor.get();
107 }
108
109 // Call this "InitializedOnMainThread" function if we would like to (1) get a value from a compiler thread which must be initialized on the main thread and (2) initialize a value if we are on the main thread.
110 Structure* getInitializedOnMainThread(const JSGlobalObject* global) const
111 {
112 return m_structure.getInitializedOnMainThread(global);
113 }
114
115 JSObject* prototypeInitializedOnMainThread(const JSGlobalObject* global) const
116 {
117 return getInitializedOnMainThread(global)->storedPrototypeObject();
118 }
119
120 JSObject* constructorInitializedOnMainThread(const JSGlobalObject* global) const
121 {
122 m_structure.getInitializedOnMainThread(global);
123 return m_constructor.get();
124 }
125
126 void visit(SlotVisitor&);
127
128 void dump(PrintStream&) const;
129
130private:
131 LazyProperty<JSGlobalObject, Structure> m_structure;
132 WriteBarrier<JSObject> m_constructor;
133};
134
135} // namespace JSC
136