/**************************************************************************
*
* Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
* All Rights Reserved.
*
* 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, sub license, 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 (including the
* next paragraph) 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 NON-INFRINGEMENT.
* IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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.
*
**************************************************************************/
#include "main/glheader.h"
#include "main/mtypes.h"
#include "main/imports.h"
#include "program/prog_cache.h"
#include "program/program.h"
struct cache_item
{
GLuint hash;
void *key;
struct gl_program *program;
struct cache_item *next;
};
struct gl_program_cache
{
struct cache_item **items;
struct cache_item *last;
GLuint size, n_items;
};
/**
* Compute hash index from state key.
*/
static GLuint
hash_key(const void *key, GLuint key_size)
{
const GLuint *ikey = (const GLuint *) key;
GLuint hash = 0, i;
/* Make a slightly better attempt at a hash function:
*/
for (i = 0; i < key_size / sizeof(*ikey); i++)
{
hash += ikey[i];
hash += (hash << 10);
hash ^= (hash >> 6);
}
return hash;
}
/**
* Rebuild/expand the hash table to accomodate more entries
*/
static void
rehash(struct gl_program_cache *cache)
{
struct cache_item **items;
struct cache_item *c, *next;
GLuint size, i;
cache->last = NULL;
size = cache->size * 3;
items
= (struct cache_item
**) malloc(size
* sizeof(*items
));
memset(items
, 0, size
* sizeof(*items
));
for (i = 0; i < cache->size; i++)
for (c = cache->items[i]; c; c = next) {
next = c->next;
c->next = items[c->hash % size];
items[c->hash % size] = c;
}
cache->items = items;
cache->size = size;
}
static void
clear_cache(struct gl_context *ctx, struct gl_program_cache *cache)
{
struct cache_item *c, *next;
GLuint i;
cache->last = NULL;
for (i = 0; i < cache->size; i++) {
for (c = cache->items[i]; c; c = next) {
next = c->next;
_mesa_reference_program(ctx, &c->program, NULL);
}
cache->items[i] = NULL;
}
cache->n_items = 0;
}
struct gl_program_cache *
_mesa_new_program_cache(void)
{
struct gl_program_cache *cache = CALLOC_STRUCT(gl_program_cache);
if (cache) {
cache->size = 17;
cache->items = (struct cache_item **)
calloc(1, cache
->size
* sizeof(struct cache_item
));
if (!cache->items) {
return NULL;
}
}
return cache;
}
void
_mesa_delete_program_cache(struct gl_context *ctx, struct gl_program_cache *cache)
{
clear_cache(ctx, cache);
}
struct gl_program *
_mesa_search_program_cache(struct gl_program_cache *cache,
const void *key, GLuint keysize)
{
if (cache->last &&
memcmp(cache
->last
->key
, key
, keysize
) == 0) {
return cache->last->program;
}
else {
const GLuint hash = hash_key(key, keysize);
struct cache_item *c;
for (c = cache->items[hash % cache->size]; c; c = c->next) {
if (c
->hash
== hash
&& memcmp(c
->key
, key
, keysize
) == 0) {
cache->last = c;
return c->program;
}
}
return NULL;
}
}
void
_mesa_program_cache_insert(struct gl_context *ctx,
struct gl_program_cache *cache,
const void *key, GLuint keysize,
struct gl_program *program)
{
const GLuint hash = hash_key(key, keysize);
struct cache_item *c = CALLOC_STRUCT(cache_item);
c->hash = hash;
c->program = program; /* no refcount change */
if (cache->n_items > cache->size * 1.5) {
if (cache->size < 1000)
rehash(cache);
else
clear_cache(ctx, cache);
}
cache->n_items++;
c->next = cache->items[hash % cache->size];
cache->items[hash % cache->size] = c;
}