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/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
/** \file
* \ingroup bli
*
* This allocation method assumes
* 1. The allocations are short-lived.
* 2. The total number of allocations is bound by a constant per thread.
*
* These two assumptions make it possible to cache and reuse relatively large buffers. They allow
* to hand out buffers that are much larger than the requested size, without the fear of running
* out of memory.
*
* The assumptions might feel a bit limiting at first, but hold true in many cases. For example,
* many algorithms need to store temporary data. With this allocator, the allocation can become
* very cheap for common cases.
*
* Many cpu-bound algorithms can benefit from being split up into several stages, whereby the
* output of one stage is written into an array that is read by the next stage. This makes them
* easier to debug, profile and optimize. Often a reason this is not done is that the memory
* allocation might be expensive. The goal of this allocator is to make this a non-issue, by
* reusing the same long buffers over and over again.
*
* All allocated buffers are 64 byte aligned, to make them as reusable as possible.
* If the requested size is too large, there is a fallback to normal allocation. The allocation
* overhead is probably very small in these cases anyway.
*
* The best way to use this allocator is to use one of the prepared containers like TemporaryVector
* and TemporaryArray.
*/
#ifndef __BLI_TEMPORARY_ALLOCATOR_H__
#define __BLI_TEMPORARY_ALLOCATOR_H__
#include "BLI_utildefines.h"
#ifdef __cplusplus
extern "C" {
#endif
#define BLI_TEMPORARY_BUFFER_ALIGNMENT 64
void *BLI_temporary_allocate(uint size);
void BLI_temporary_deallocate(void *buffer);
#ifdef __cplusplus
}
#endif
#endif /* __BLI_TEMPORARY_ALLOCATOR_H__ */
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