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/*
* Copyright (C) 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#ifndef WTF_Alignment_h
#define WTF_Alignment_h
#include <algorithm>
#include <stdint.h>
namespace WTF {
#if COMPILER(GCC)
#define WTF_ALIGN_OF(type) __alignof__(type)
#define WTF_ALIGNED(variable_type, variable, n) variable_type variable __attribute__((__aligned__(n)))
#elif COMPILER(MSVC)
#define WTF_ALIGN_OF(type) __alignof(type)
#define WTF_ALIGNED(variable_type, variable, n) __declspec(align(n)) variable_type variable
#else
#error WTF_ALIGN macros need alignment control.
#endif
#if COMPILER(GCC)
typedef char __attribute__((__may_alias__)) AlignedBufferChar;
#else
typedef char AlignedBufferChar;
#endif
template<size_t size, size_t alignment> struct AlignedBuffer;
template<size_t size> struct AlignedBuffer<size, 1> { AlignedBufferChar buffer[size]; };
template<size_t size> struct AlignedBuffer<size, 2> { WTF_ALIGNED(AlignedBufferChar, buffer[size], 2); };
template<size_t size> struct AlignedBuffer<size, 4> { WTF_ALIGNED(AlignedBufferChar, buffer[size], 4); };
template<size_t size> struct AlignedBuffer<size, 8> { WTF_ALIGNED(AlignedBufferChar, buffer[size], 8); };
template<size_t size> struct AlignedBuffer<size, 16> { WTF_ALIGNED(AlignedBufferChar, buffer[size], 16); };
template<size_t size> struct AlignedBuffer<size, 32> { WTF_ALIGNED(AlignedBufferChar, buffer[size], 32); };
template<size_t size> struct AlignedBuffer<size, 64> { WTF_ALIGNED(AlignedBufferChar, buffer[size], 64); };
template <size_t size, size_t alignment>
void swap(AlignedBuffer<size, alignment>& a, AlignedBuffer<size, alignment>& b)
{
for (size_t i = 0; i < size; ++i)
std::swap(a.buffer[i], b.buffer[i]);
}
template <uintptr_t mask>
inline bool isAlignedTo(const void* pointer)
{
return !(reinterpret_cast<uintptr_t>(pointer) & mask);
}
}
#endif // WTF_Alignment_h
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