1/*
2 * Copyright (C) 2014 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#ifndef DFGSafepoint_h
27#define DFGSafepoint_h
28
29#if ENABLE(DFG_JIT)
30
31#include <wtf/Vector.h>
32
33namespace JSC {
34
35class SlotVisitor;
36class VM;
37
38namespace DFG {
39
40class Scannable;
41struct Plan;
42
43class Safepoint {
44public:
45    class Result {
46    public:
47        Result()
48            : m_didGetCancelled(false)
49            , m_wasChecked(true)
50        {
51        }
52
53        ~Result();
54
55        bool didGetCancelled();
56
57    private:
58        friend class Safepoint;
59
60        bool m_didGetCancelled;
61        bool m_wasChecked;
62    };
63
64    Safepoint(Plan&, Result&);
65    ~Safepoint();
66
67    void add(Scannable*);
68
69    void begin();
70
71    void checkLivenessAndVisitChildren(SlotVisitor&);
72    bool isKnownToBeLiveDuringGC();
73    void cancel();
74
75    VM& vm() const;
76
77private:
78    Plan& m_plan;
79    Vector<Scannable*> m_scannables;
80    bool m_didCallBegin;
81    Result& m_result;
82};
83
84} } // namespace JSC::DFG
85
86#endif // ENABLE(DFG_JIT)
87
88#endif // DFGSafepoint_h
89
90