src/mesa/program/prog_cache.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2003 VMware, Inc.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28
  29 #include "main/glheader.h"
  30 #include "main/mtypes.h"
  31 #include "util/imports.h"
  32 #include "main/shaderobj.h"
  33 #include "program/prog_cache.h"
  34 #include "program/program.h"
  35 #include "util/u_memory.h"
  36
  37
  38 struct cache_item
  39 {
  40    GLuint hash;
  41    unsigned keysize;
  42    void *key;
  43    struct gl_program *program;
  44    struct cache_item *next;
  45 };
  46
  47 struct gl_program_cache
  48 {
  49    struct cache_item **items;
  50    struct cache_item *last;
  51    GLuint size, n_items;
  52 };
  53
  54
  55
  56 /**
  57  * Compute hash index from state key.
  58  */
  59 static GLuint
  60 hash_key(const void *key, GLuint key_size)
  61 {
  62    const GLuint *ikey = (const GLuint *) key;
  63    GLuint hash = 0, i;
  64
  65    assert(key_size >= 4);
  66
  67    /* Make a slightly better attempt at a hash function:
  68     */
  69    for (i = 0; i < key_size / sizeof(*ikey); i++)
  70    {
  71       hash += ikey[i];
  72       hash += (hash << 10);
  73       hash ^= (hash >> 6);
  74    }
  75
  76    return hash;
  77 }
  78
  79
  80 /**
  81  * Rebuild/expand the hash table to accommodate more entries
  82  */
  83 static void
  84 rehash(struct gl_program_cache *cache)
  85 {
  86    struct cache_item **items;
  87    struct cache_item *c, *next;
  88    GLuint size, i;
  89
  90    cache->last = NULL;
  91
  92    size = cache->size * 3;
  93    items = malloc(size * sizeof(*items));
  94    memset(items, 0, size * sizeof(*items));
  95
  96    for (i = 0; i < cache->size; i++)
  97       for (c = cache->items[i]; c; c = next) {
  98          next = c->next;
  99          c->next = items[c->hash % size];
 100          items[c->hash % size] = c;
 101       }
 102
 103    free(cache->items);
 104    cache->items = items;
 105    cache->size = size;
 106 }
 107
 108
 109 static void
 110 clear_cache(struct gl_context *ctx, struct gl_program_cache *cache,
 111             GLboolean shader)
 112 {
 113    struct cache_item *c, *next;
 114    GLuint i;
 115
 116    cache->last = NULL;
 117
 118    for (i = 0; i < cache->size; i++) {
 119       for (c = cache->items[i]; c; c = next) {
 120          next = c->next;
 121          free(c->key);
 122          if (shader) {
 123             _mesa_reference_shader_program(ctx,
 124                                            (struct gl_shader_program **)&c->program,
 125                                            NULL);
 126          } else {
 127             _mesa_reference_program(ctx, &c->program, NULL);
 128          }
 129          free(c);
 130       }
 131       cache->items[i] = NULL;
 132    }
 133
 134
 135    cache->n_items = 0;
 136 }
 137
 138
 139
 140 struct gl_program_cache *
 141 _mesa_new_program_cache(void)
 142 {
 143    struct gl_program_cache *cache = CALLOC_STRUCT(gl_program_cache);
 144    if (cache) {
 145       cache->size = 17;
 146       cache->items =
 147          calloc(cache->size, sizeof(struct cache_item *));
 148       if (!cache->items) {
 149          free(cache);
 150          return NULL;
 151       }
 152    }
 153    return cache;
 154 }
 155
 156
 157 void
 158 _mesa_delete_program_cache(struct gl_context *ctx, struct gl_program_cache *cache)
 159 {
 160    clear_cache(ctx, cache, GL_FALSE);
 161    free(cache->items);
 162    free(cache);
 163 }
 164
 165 void
 166 _mesa_delete_shader_cache(struct gl_context *ctx,
 167                           struct gl_program_cache *cache)
 168 {
 169    clear_cache(ctx, cache, GL_TRUE);
 170    free(cache->items);
 171    free(cache);
 172 }
 173
 174
 175 struct gl_program *
 176 _mesa_search_program_cache(struct gl_program_cache *cache,
 177                            const void *key, GLuint keysize)
 178 {
 179    if (cache->last &&
 180        cache->last->keysize == keysize &&
 181        memcmp(cache->last->key, key, keysize) == 0) {
 182       return cache->last->program;
 183    }
 184    else {
 185       const GLuint hash = hash_key(key, keysize);
 186       struct cache_item *c;
 187
 188       for (c = cache->items[hash % cache->size]; c; c = c->next) {
 189          if (c->hash == hash &&
 190              c->keysize == keysize &&
 191              memcmp(c->key, key, keysize) == 0) {
 192
 193             cache->last = c;
 194             return c->program;
 195          }
 196       }
 197
 198       return NULL;
 199    }
 200 }
 201
 202
 203 void
 204 _mesa_program_cache_insert(struct gl_context *ctx,
 205                            struct gl_program_cache *cache,
 206                            const void *key, GLuint keysize,
 207                            struct gl_program *program)
 208 {
 209    const GLuint hash = hash_key(key, keysize);
 210    struct cache_item *c = CALLOC_STRUCT(cache_item);
 211
 212    c->hash = hash;
 213
 214    c->key = malloc(keysize);
 215    memcpy(c->key, key, keysize);
 216    c->keysize = keysize;
 217
 218    c->program = program;  /* no refcount change */
 219
 220    if (cache->n_items > cache->size * 1.5) {
 221       if (cache->size < 1000)
 222          rehash(cache);
 223       else
 224          clear_cache(ctx, cache, GL_FALSE);
 225    }
 226
 227    cache->n_items++;
 228    c->next = cache->items[hash % cache->size];
 229    cache->items[hash % cache->size] = c;
 230 }
 231
 232 void
 233 _mesa_shader_cache_insert(struct gl_context *ctx,
 234                           struct gl_program_cache *cache,
 235                           const void *key, GLuint keysize,
 236                           struct gl_shader_program *program)
 237 {
 238    const GLuint hash = hash_key(key, keysize);
 239    struct cache_item *c = CALLOC_STRUCT(cache_item);
 240
 241    c->hash = hash;
 242
 243    c->key = malloc(keysize);
 244    memcpy(c->key, key, keysize);
 245    c->keysize = keysize;
 246
 247    c->program = (struct gl_program *)program;  /* no refcount change */
 248
 249    if (cache->n_items > cache->size * 1.5) {
 250       if (cache->size < 1000)
 251          rehash(cache);
 252       else
 253          clear_cache(ctx, cache, GL_TRUE);
 254    }
 255
 256    cache->n_items++;
 257    c->next = cache->items[hash % cache->size];
 258    cache->items[hash % cache->size] = c;
 259 }