diff options
Diffstat (limited to 'src/gallium/auxiliary/cso_cache/cso_hash.c')
-rw-r--r-- | src/gallium/auxiliary/cso_cache/cso_hash.c | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/cso_cache/cso_hash.c b/src/gallium/auxiliary/cso_cache/cso_hash.c new file mode 100644 index 0000000000..4e7664f9bf --- /dev/null +++ b/src/gallium/auxiliary/cso_cache/cso_hash.c @@ -0,0 +1,439 @@ +/************************************************************************** + * + * Copyright 2007 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. + * + **************************************************************************/ + + /* + * Authors: + * Zack Rusin <zack@tungstengraphics.com> + */ + +#include "pipe/p_debug.h" +#include "util/u_memory.h" + +#include "cso_hash.h" + +#define MAX(a, b) ((a > b) ? (a) : (b)) + +static const int MinNumBits = 4; + +static const unsigned char prime_deltas[] = { + 0, 0, 1, 3, 1, 5, 3, 3, 1, 9, 7, 5, 3, 9, 25, 3, + 1, 21, 3, 21, 7, 15, 9, 5, 3, 29, 15, 0, 0, 0, 0, 0 +}; + +static int primeForNumBits(int numBits) +{ + return (1 << numBits) + prime_deltas[numBits]; +} + +/* + Returns the smallest integer n such that + primeForNumBits(n) >= hint. +*/ +static int countBits(int hint) +{ + int numBits = 0; + int bits = hint; + + while (bits > 1) { + bits >>= 1; + numBits++; + } + + if (numBits >= (int)sizeof(prime_deltas)) { + numBits = sizeof(prime_deltas) - 1; + } else if (primeForNumBits(numBits) < hint) { + ++numBits; + } + return numBits; +} + +struct cso_node { + struct cso_node *next; + unsigned key; + void *value; +}; + +struct cso_hash_data { + struct cso_node *fakeNext; + struct cso_node **buckets; + int size; + int nodeSize; + short userNumBits; + short numBits; + int numBuckets; +}; + +struct cso_hash { + union { + struct cso_hash_data *d; + struct cso_node *e; + } data; +}; + +static void *cso_data_allocate_node(struct cso_hash_data *hash) +{ + return MALLOC(hash->nodeSize); +} + +static void cso_free_node(struct cso_node *node) +{ + FREE(node); +} + +static struct cso_node * +cso_hash_create_node(struct cso_hash *hash, + unsigned akey, void *avalue, + struct cso_node **anextNode) +{ + struct cso_node *node = cso_data_allocate_node(hash->data.d); + + if (!node) + return NULL; + + node->key = akey; + node->value = avalue; + + node->next = (struct cso_node*)(*anextNode); + *anextNode = node; + ++hash->data.d->size; + return node; +} + +static void cso_data_rehash(struct cso_hash_data *hash, int hint) +{ + if (hint < 0) { + hint = countBits(-hint); + if (hint < MinNumBits) + hint = MinNumBits; + hash->userNumBits = (short)hint; + while (primeForNumBits(hint) < (hash->size >> 1)) + ++hint; + } else if (hint < MinNumBits) { + hint = MinNumBits; + } + + if (hash->numBits != hint) { + struct cso_node *e = (struct cso_node *)(hash); + struct cso_node **oldBuckets = hash->buckets; + int oldNumBuckets = hash->numBuckets; + int i = 0; + + hash->numBits = (short)hint; + hash->numBuckets = primeForNumBits(hint); + hash->buckets = MALLOC(sizeof(struct cso_node*) * hash->numBuckets); + for (i = 0; i < hash->numBuckets; ++i) + hash->buckets[i] = e; + + for (i = 0; i < oldNumBuckets; ++i) { + struct cso_node *firstNode = oldBuckets[i]; + while (firstNode != e) { + unsigned h = firstNode->key; + struct cso_node *lastNode = firstNode; + struct cso_node *afterLastNode; + struct cso_node **beforeFirstNode; + + while (lastNode->next != e && lastNode->next->key == h) + lastNode = lastNode->next; + + afterLastNode = lastNode->next; + beforeFirstNode = &hash->buckets[h % hash->numBuckets]; + while (*beforeFirstNode != e) + beforeFirstNode = &(*beforeFirstNode)->next; + lastNode->next = *beforeFirstNode; + *beforeFirstNode = firstNode; + firstNode = afterLastNode; + } + } + FREE(oldBuckets); + } +} + +static void cso_data_might_grow(struct cso_hash_data *hash) +{ + if (hash->size >= hash->numBuckets) + cso_data_rehash(hash, hash->numBits + 1); +} + +static void cso_data_has_shrunk(struct cso_hash_data *hash) +{ + if (hash->size <= (hash->numBuckets >> 3) && + hash->numBits > hash->userNumBits) { + int max = MAX(hash->numBits-2, hash->userNumBits); + cso_data_rehash(hash, max); + } +} + +static struct cso_node *cso_data_first_node(struct cso_hash_data *hash) +{ + struct cso_node *e = (struct cso_node *)(hash); + struct cso_node **bucket = hash->buckets; + int n = hash->numBuckets; + while (n--) { + if (*bucket != e) + return *bucket; + ++bucket; + } + return e; +} + +static struct cso_node **cso_hash_find_node(struct cso_hash *hash, unsigned akey) +{ + struct cso_node **node; + + if (hash->data.d->numBuckets) { + node = (struct cso_node **)(&hash->data.d->buckets[akey % hash->data.d->numBuckets]); + assert(*node == hash->data.e || (*node)->next); + while (*node != hash->data.e && (*node)->key != akey) + node = &(*node)->next; + } else { + node = (struct cso_node **)((const struct cso_node * const *)(&hash->data.e)); + } + return node; +} + +struct cso_hash_iter cso_hash_insert(struct cso_hash *hash, + unsigned key, void *data) +{ + cso_data_might_grow(hash->data.d); + + { + struct cso_node **nextNode = cso_hash_find_node(hash, key); + struct cso_node *node = cso_hash_create_node(hash, key, data, nextNode); + if (!node) { + struct cso_hash_iter null_iter = {hash, 0}; + return null_iter; + } + + { + struct cso_hash_iter iter = {hash, node}; + return iter; + } + } +} + +struct cso_hash * cso_hash_create(void) +{ + struct cso_hash *hash = MALLOC_STRUCT(cso_hash); + if (!hash) + return NULL; + + hash->data.d = MALLOC_STRUCT(cso_hash_data); + if (!hash->data.d) { + FREE(hash); + return NULL; + } + + hash->data.d->fakeNext = 0; + hash->data.d->buckets = 0; + hash->data.d->size = 0; + hash->data.d->nodeSize = sizeof(struct cso_node); + hash->data.d->userNumBits = (short)MinNumBits; + hash->data.d->numBits = 0; + hash->data.d->numBuckets = 0; + + return hash; +} + +void cso_hash_delete(struct cso_hash *hash) +{ + struct cso_node *e_for_x = (struct cso_node *)(hash->data.d); + struct cso_node **bucket = (struct cso_node **)(hash->data.d->buckets); + int n = hash->data.d->numBuckets; + while (n--) { + struct cso_node *cur = *bucket++; + while (cur != e_for_x) { + struct cso_node *next = cur->next; + cso_free_node(cur); + cur = next; + } + } + FREE(hash->data.d->buckets); + FREE(hash->data.d); + FREE(hash); +} + +struct cso_hash_iter cso_hash_find(struct cso_hash *hash, + unsigned key) +{ + struct cso_node **nextNode = cso_hash_find_node(hash, key); + struct cso_hash_iter iter = {hash, *nextNode}; + return iter; +} + +unsigned cso_hash_iter_key(struct cso_hash_iter iter) +{ + if (!iter.node || iter.hash->data.e == iter.node) + return 0; + return iter.node->key; +} + +void * cso_hash_iter_data(struct cso_hash_iter iter) +{ + if (!iter.node || iter.hash->data.e == iter.node) + return 0; + return iter.node->value; +} + +static struct cso_node *cso_hash_data_next(struct cso_node *node) +{ + union { + struct cso_node *next; + struct cso_node *e; + struct cso_hash_data *d; + } a; + int start; + struct cso_node **bucket; + int n; + + a.next = node->next; + if (!a.next) { + debug_printf("iterating beyond the last element\n"); + return 0; + } + if (a.next->next) + return a.next; + + start = (node->key % a.d->numBuckets) + 1; + bucket = a.d->buckets + start; + n = a.d->numBuckets - start; + while (n--) { + if (*bucket != a.e) + return *bucket; + ++bucket; + } + return a.e; +} + + +static struct cso_node *cso_hash_data_prev(struct cso_node *node) +{ + union { + struct cso_node *e; + struct cso_hash_data *d; + } a; + int start; + struct cso_node *sentinel; + struct cso_node **bucket; + + a.e = node; + while (a.e->next) + a.e = a.e->next; + + if (node == a.e) + start = a.d->numBuckets - 1; + else + start = node->key % a.d->numBuckets; + + sentinel = node; + bucket = a.d->buckets + start; + while (start >= 0) { + if (*bucket != sentinel) { + struct cso_node *prev = *bucket; + while (prev->next != sentinel) + prev = prev->next; + return prev; + } + + sentinel = a.e; + --bucket; + --start; + } + debug_printf("iterating backward beyond first element\n"); + return a.e; +} + +struct cso_hash_iter cso_hash_iter_next(struct cso_hash_iter iter) +{ + struct cso_hash_iter next = {iter.hash, cso_hash_data_next(iter.node)}; + return next; +} + +int cso_hash_iter_is_null(struct cso_hash_iter iter) +{ + if (!iter.node || iter.node == iter.hash->data.e) + return 1; + return 0; +} + +void * cso_hash_take(struct cso_hash *hash, + unsigned akey) +{ + struct cso_node **node = cso_hash_find_node(hash, akey); + if (*node != hash->data.e) { + void *t = (*node)->value; + struct cso_node *next = (*node)->next; + cso_free_node(*node); + *node = next; + --hash->data.d->size; + cso_data_has_shrunk(hash->data.d); + return t; + } + return 0; +} + +struct cso_hash_iter cso_hash_iter_prev(struct cso_hash_iter iter) +{ + struct cso_hash_iter prev = {iter.hash, + cso_hash_data_prev(iter.node)}; + return prev; +} + +struct cso_hash_iter cso_hash_first_node(struct cso_hash *hash) +{ + struct cso_hash_iter iter = {hash, cso_data_first_node(hash->data.d)}; + return iter; +} + +int cso_hash_size(struct cso_hash *hash) +{ + return hash->data.d->size; +} + +struct cso_hash_iter cso_hash_erase(struct cso_hash *hash, struct cso_hash_iter iter) +{ + struct cso_hash_iter ret = iter; + struct cso_node *node = iter.node; + struct cso_node **node_ptr; + + if (node == hash->data.e) + return iter; + + ret = cso_hash_iter_next(ret); + node_ptr = (struct cso_node**)(&hash->data.d->buckets[node->key % hash->data.d->numBuckets]); + while (*node_ptr != node) + node_ptr = &(*node_ptr)->next; + *node_ptr = node->next; + cso_free_node(node); + --hash->data.d->size; + return ret; +} + +boolean cso_hash_contains(struct cso_hash *hash, unsigned key) +{ + struct cso_node **node = cso_hash_find_node(hash, key); + return (*node != hash->data.e); +} |