/*

* Copyright (C) 2011 Apple Inc. All rights reserved.

*

* Redistribution and use in source and binary forms, with or without

* modification, are permitted provided that the following conditions

* are met:

* 1. Redistributions of source code must retain the above copyright

* notice, this list of conditions and the following disclaimer.

* 2. Redistributions in binary form must reproduce the above copyright

* notice, this list of conditions and the following disclaimer in the

* documentation and/or other materials provided with the distribution.

*

* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY

* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR

* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

#ifndef CopiedAllocator_h

#define CopiedAllocator_h

#include "CopiedBlock.h"

namespace JSC {

class CopiedAllocator {

friend class JIT;

public:

CopiedAllocator();

void* allocate(size_t);

bool fitsInCurrentBlock(size_t);

bool wasLastAllocation(void*, size_t);

void startedCopying();

void resetCurrentBlock(CopiedBlock*);

size_t currentCapacity();

private:

CopiedBlock* currentBlock() { return m_currentBlock; }

char* m_currentOffset;

CopiedBlock* m_currentBlock;

};

inline CopiedAllocator::CopiedAllocator()

: m_currentOffset(0)

, m_currentBlock(0)

{

}

inline void* CopiedAllocator::allocate(size_t bytes)

{

ASSERT(m_currentOffset);

ASSERT(is8ByteAligned(reinterpret_cast<void*>(bytes)));

ASSERT(fitsInCurrentBlock(bytes));

void* ptr = static_cast<void*>(m_currentOffset);

m_currentOffset += bytes;

ASSERT(is8ByteAligned(ptr));

return ptr;

}

inline bool CopiedAllocator::fitsInCurrentBlock(size_t bytes)

{

return m_currentOffset + bytes < reinterpret_cast<char*>(m_currentBlock) + HeapBlock::s_blockSize && m_currentOffset + bytes > m_currentOffset;

}

inline bool CopiedAllocator::wasLastAllocation(void* ptr, size_t size)

{

return static_cast<char*>(ptr) + size == m_currentOffset && ptr > m_currentBlock && ptr < reinterpret_cast<char*>(m_currentBlock) + HeapBlock::s_blockSize;

}

inline void CopiedAllocator::startedCopying()

{

if (m_currentBlock)

m_currentBlock->m_offset = static_cast<void*>(m_currentOffset);

m_currentOffset = 0;

m_currentBlock = 0;

}

inline void CopiedAllocator::resetCurrentBlock(CopiedBlock* newBlock)

{

if (m_currentBlock)

m_currentBlock->m_offset = static_cast<void*>(m_currentOffset);

m_currentBlock = newBlock;

m_currentOffset = static_cast<char*>(newBlock->m_offset);

}

inline size_t CopiedAllocator::currentCapacity()

{

return m_currentBlock->capacity();

}

} // namespace JSC

#endif