src/gallium/drivers/r300/compiler/memory_pool.c

   1 /*
   2  * Copyright 2009 Nicolai Hähnle <nhaehnle@gmail.com>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * on the rights to use, copy, modify, merge, publish, distribute, sub
   8  * license, and/or sell copies of the Software, and to permit persons to whom
   9  * the Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  18  * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
  19  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  20  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  21  * USE OR OTHER DEALINGS IN THE SOFTWARE. */
  22
  23 #include "memory_pool.h"
  24
  25 #include <assert.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28
  29
  30 #define POOL_LARGE_ALLOC 4096
  31 #define POOL_ALIGN 8
  32
  33
  34 struct memory_block {
  35         struct memory_block * next;
  36 };
  37
  38 void memory_pool_init(struct memory_pool * pool)
  39 {
  40         memset(pool, 0, sizeof(struct memory_pool));
  41 }
  42
  43
  44 void memory_pool_destroy(struct memory_pool * pool)
  45 {
  46         while(pool->blocks) {
  47                 struct memory_block * block = pool->blocks;
  48                 pool->blocks = block->next;
  49                 free(block);
  50         }
  51 }
  52
  53 static void refill_pool(struct memory_pool * pool)
  54 {
  55         unsigned int blocksize = pool->total_allocated;
  56         struct memory_block * newblock;
  57
  58         if (!blocksize)
  59                 blocksize = 2*POOL_LARGE_ALLOC;
  60
  61         newblock = malloc(blocksize);
  62         newblock->next = pool->blocks;
  63         pool->blocks = newblock;
  64
  65         pool->head = (unsigned char*)(newblock + 1);
  66         pool->end = ((unsigned char*)newblock) + blocksize;
  67         pool->total_allocated += blocksize;
  68 }
  69
  70
  71 void * memory_pool_malloc(struct memory_pool * pool, unsigned int bytes)
  72 {
  73         if (bytes < POOL_LARGE_ALLOC) {
  74                 void * ptr;
  75
  76                 if (pool->head + bytes > pool->end)
  77                         refill_pool(pool);
  78
  79                 assert(pool->head + bytes <= pool->end);
  80
  81                 ptr = pool->head;
  82
  83                 pool->head += bytes;
  84                 pool->head = (unsigned char*)(((unsigned long)pool->head + POOL_ALIGN - 1) & ~(POOL_ALIGN - 1));
  85
  86                 return ptr;
  87         } else {
  88                 struct memory_block * block = malloc(bytes + sizeof(struct memory_block));
  89
  90                 block->next = pool->blocks;
  91                 pool->blocks = block;
  92
  93                 return (block + 1);
  94         }
  95 }
  96
  97