1/*
2 * Copyright (C) 2016-2017 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 "JSGlobalObject.h"
29#include "SlotVisitor.h"
30#include "WriteBarrier.h"
31
32namespace JSC {
33
34class InternalFunctionAllocationProfile {
35public:
36 Structure* structure() { return m_structure.get(); }
37 Structure* createAllocationStructureFromBase(VM&, JSGlobalObject*, JSCell* owner, JSObject* prototype, Structure* base);
38
39 void clear() { m_structure.clear(); }
40 void visitAggregate(SlotVisitor& visitor) { visitor.append(m_structure); }
41
42private:
43 WriteBarrier<Structure> m_structure;
44};
45
46inline Structure* InternalFunctionAllocationProfile::createAllocationStructureFromBase(VM& vm, JSGlobalObject* globalObject, JSCell* owner, JSObject* prototype, Structure* baseStructure)
47{
48 ASSERT(!m_structure || m_structure.get()->classInfo() != baseStructure->classInfo());
49 ASSERT(baseStructure->hasMonoProto());
50
51 Structure* structure;
52 // FIXME: Implement polymorphic prototypes for subclasses of builtin types:
53 // https://bugs.webkit.org/show_bug.cgi?id=177318
54 if (prototype == baseStructure->storedPrototype())
55 structure = baseStructure;
56 else
57 structure = vm.structureCache.emptyStructureForPrototypeFromBaseStructure(globalObject, prototype, baseStructure);
58
59 // Ensure that if another thread sees the structure, it will see it properly created.
60 WTF::storeStoreFence();
61
62 m_structure.set(vm, owner, structure);
63 return m_structure.get();
64}
65
66} // namespace JSC
67