1/*
2 * Copyright (C) 2008 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 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of Apple Inc. ("Apple") nor the names of
14 * its contributors may be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#pragma once
30
31#include "Label.h"
32
33namespace JSC {
34
35class Identifier;
36
37class LabelScope {
38WTF_MAKE_NONCOPYABLE(LabelScope);
39public:
40 enum Type { Loop, Switch, NamedLabel };
41
42 LabelScope(Type type, const Identifier* name, int scopeDepth, Ref<Label>&& breakTarget, RefPtr<Label>&& continueTarget)
43 : m_refCount(0)
44 , m_type(type)
45 , m_name(name)
46 , m_scopeDepth(scopeDepth)
47 , m_breakTarget(WTFMove(breakTarget))
48 , m_continueTarget(WTFMove(continueTarget))
49 {
50 }
51
52 Label& breakTarget() const { return m_breakTarget.get(); }
53 Label* continueTarget() const { return m_continueTarget.get(); }
54
55 Type type() const { return m_type; }
56 const Identifier* name() const { return m_name; }
57 int scopeDepth() const { return m_scopeDepth; }
58
59 void ref() { ++m_refCount; }
60 void deref()
61 {
62 --m_refCount;
63 ASSERT(m_refCount >= 0);
64 }
65 int refCount() const { return m_refCount; }
66 bool hasOneRef() const { return m_refCount == 1; }
67
68 bool breakTargetMayBeBound() const
69 {
70 if (!hasOneRef())
71 return true;
72 if (!m_breakTarget->hasOneRef())
73 return true;
74 return m_breakTarget->isBound();
75 }
76
77private:
78 int m_refCount;
79 Type m_type;
80 const Identifier* m_name;
81 int m_scopeDepth;
82 Ref<Label> m_breakTarget;
83 RefPtr<Label> m_continueTarget;
84};
85
86} // namespace JSC
87