Files
xahaud/modules/beast_basics/memory/beast_MemoryAlignment.h
2013-06-17 07:09:33 -07:00

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/*============================================================================*/
/*
VFLib: https://github.com/vinniefalco/VFLib
Copyright (C) 2008 by Vinnie Falco <vinnie.falco@gmail.com>
This library contains portions of other open source products covered by
separate licenses. Please see the corresponding source files for specific
terms.
VFLib is provided under the terms of The MIT License (MIT):
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
IN THE SOFTWARE.
*/
/*============================================================================*/
#ifndef BEAST_MEMORYALIGNMENT_BEASTHEADER
#define BEAST_MEMORYALIGNMENT_BEASTHEADER
namespace Memory
{
// Constants
const int cacheLineAlignBits = 6; // 64 bytes
const int cacheLineAlignBytes = 1 << cacheLineAlignBits;
const int cacheLineAlignMask = cacheLineAlignBytes - 1;
const int allocAlignBits = 3; // 8 bytes
const int allocAlignBytes = 1 << allocAlignBits;
const int allocAlignMask = allocAlignBytes - 1;
// Returns the number of bytes needed to advance p to the correct alignment
template <typename P>
inline size_t bytesNeededForAlignment (P const* const p)
{
return (allocAlignBytes - (uintptr_t (p) & allocAlignMask))
& allocAlignMask;
}
// Returns the number of bytes to make "bytes" an aligned size
inline size_t sizeAdjustedForAlignment (const size_t bytes)
{
return (bytes + allocAlignMask) & ~allocAlignMask;
}
// Returns a pointer with alignment added.
template <typename P>
inline P* pointerAdjustedForAlignment (P* const p)
{
return reinterpret_cast <P*> (reinterpret_cast <char*> (p) +
bytesNeededForAlignment (p));
}
}
#endif