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42 #ifndef QDECLARATIVEJSMEMORYPOOL_P_H
43 #define QDECLARATIVEJSMEMORYPOOL_P_H
49 // This file is not part of the Qt API. It exists purely as an
50 // implementation detail. This header file may change from version to
51 // version without notice, or even be removed.
56 #include "private/qdeclarativejsglobal_p.h"
58 #include <QtCore/qglobal.h>
59 #include <QtCore/qshareddata.h>
63 QT_QML_BEGIN_NAMESPACE
65 namespace QDeclarativeJS {
67 class QML_PARSER_EXPORT MemoryPool : public QSharedData
70 enum { maxBlockCount = -1 };
71 enum { defaultBlockSize = 1 << 12 };
74 m_blockIndex = maxBlockCount;
78 m_currentBlockSize = 0;
81 virtual ~MemoryPool() {
82 for (int index = 0; index < m_blockIndex + 1; ++index)
83 qFree(m_storage[index]);
88 char *allocate(int bytes) {
89 bytes += (8 - bytes) & 7; // ensure multiple of 8 bytes (maintain alignment)
90 if (m_currentBlock == 0 || m_currentBlockSize < m_currentIndex + bytes) {
92 m_currentBlockSize = defaultBlockSize << m_blockIndex;
94 m_storage = reinterpret_cast<char**>(qRealloc(m_storage, sizeof(char*) * (1 + m_blockIndex)));
95 m_currentBlock = m_storage[m_blockIndex] = reinterpret_cast<char*>(qMalloc(m_currentBlockSize));
96 ::memset(m_currentBlock, 0, m_currentBlockSize);
98 m_currentIndex = (8 - quintptr(m_currentBlock)) & 7; // ensure first chunk is 64-bit aligned
99 Q_ASSERT(m_currentIndex + bytes <= m_currentBlockSize);
102 char *p = reinterpret_cast<char *>
103 (m_currentBlock + m_currentIndex);
105 m_currentIndex += bytes;
110 int bytesAllocated() const {
112 for (int index = 0; index < m_blockIndex; ++index)
113 bytes += (defaultBlockSize << index);
114 bytes += m_currentIndex;
121 char *m_currentBlock;
122 int m_currentBlockSize;
126 Q_DISABLE_COPY(MemoryPool)
129 } // namespace QDeclarativeJS