1/*
2 * Copyright (C) 2009 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 ParserArena_h
27#define ParserArena_h
28
29#include "Identifier.h"
30#include <wtf/SegmentedVector.h>
31
32namespace JSC {
33
34 class ParserArenaDeletable;
35 class ParserArenaRefCounted;
36
37 class IdentifierArena : public FastAllocBase {
38 public:
39 ALWAYS_INLINE const Identifier& makeIdentifier(JSGlobalData*, const UChar* characters, size_t length);
40 const Identifier& makeNumericIdentifier(JSGlobalData*, double number);
41
42 void clear() { m_identifiers.clear(); }
43 bool isEmpty() const { return m_identifiers.isEmpty(); }
44
45 private:
46 typedef SegmentedVector<Identifier, 64> IdentifierVector;
47 IdentifierVector m_identifiers;
48 };
49
50 ALWAYS_INLINE const Identifier& IdentifierArena::makeIdentifier(JSGlobalData* globalData, const UChar* characters, size_t length)
51 {
52 m_identifiers.append(value: Identifier(globalData, characters, length));
53 return m_identifiers.last();
54 }
55
56 inline const Identifier& IdentifierArena::makeNumericIdentifier(JSGlobalData* globalData, double number)
57 {
58 m_identifiers.append(value: Identifier(globalData, UString::from(number)));
59 return m_identifiers.last();
60 }
61
62 class ParserArena : Noncopyable {
63 public:
64 ParserArena();
65 ~ParserArena();
66
67 void swap(ParserArena& otherArena)
68 {
69 std::swap(a&: m_freeableMemory, b&: otherArena.m_freeableMemory);
70 std::swap(a&: m_freeablePoolEnd, b&: otherArena.m_freeablePoolEnd);
71 m_identifierArena.swap(o&: otherArena.m_identifierArena);
72 m_freeablePools.swap(other&: otherArena.m_freeablePools);
73 m_deletableObjects.swap(other&: otherArena.m_deletableObjects);
74 m_refCountedObjects.swap(other&: otherArena.m_refCountedObjects);
75 }
76
77 void* allocateFreeable(size_t size)
78 {
79 ASSERT(size);
80 ASSERT(size <= freeablePoolSize);
81 size_t alignedSize = alignSize(size);
82 ASSERT(alignedSize <= freeablePoolSize);
83 if (UNLIKELY(static_cast<size_t>(m_freeablePoolEnd - m_freeableMemory) < alignedSize))
84 allocateFreeablePool();
85 void* block = m_freeableMemory;
86 m_freeableMemory += alignedSize;
87 return block;
88 }
89
90 void* allocateDeletable(size_t size)
91 {
92 ParserArenaDeletable* deletable = static_cast<ParserArenaDeletable*>(fastMalloc(size));
93 m_deletableObjects.append(val: deletable);
94 return deletable;
95 }
96
97 void derefWithArena(PassRefPtr<ParserArenaRefCounted>);
98 bool contains(ParserArenaRefCounted*) const;
99 ParserArenaRefCounted* last() const;
100 void removeLast();
101
102 bool isEmpty() const;
103 void reset();
104
105 IdentifierArena& identifierArena() { return *m_identifierArena; }
106
107 private:
108 static const size_t freeablePoolSize = 8000;
109
110 static size_t alignSize(size_t size)
111 {
112 return (size + sizeof(WTF::AllocAlignmentInteger) - 1) & ~(sizeof(WTF::AllocAlignmentInteger) - 1);
113 }
114
115 void* freeablePool();
116 void allocateFreeablePool();
117 void deallocateObjects();
118
119 char* m_freeableMemory;
120 char* m_freeablePoolEnd;
121
122 OwnPtr<IdentifierArena> m_identifierArena;
123 Vector<void*> m_freeablePools;
124 Vector<ParserArenaDeletable*> m_deletableObjects;
125 Vector<RefPtr<ParserArenaRefCounted> > m_refCountedObjects;
126 };
127
128}
129
130#endif
131

source code of qtscript/src/3rdparty/javascriptcore/JavaScriptCore/parser/ParserArena.h