[Mesa-dev] [PATCH 1/3] mesa: add set support (stores a set of pointers)
Brian Paul
brianp at vmware.com
Wed Dec 5 07:32:37 PST 2012
On 12/04/2012 04:55 PM, Jordan Justen wrote:
> From: Eric Anholt<eric at anholt.net>
>
> From: git://people.freedesktop.org/~anholt/hash_table
>
> Reviewed-by: Jordan Justen<jordan.l.justen at intel.com>
> [jordan.l.justen at intel.com: minor rework for mesa]
> Signed-off-by: Jordan Justen<jordan.l.justen at intel.com>
> ---
> src/mesa/SConscript | 1 +
> src/mesa/main/set.c | 349 ++++++++++++++++++++++++++++++++++++++++++++++++++
> src/mesa/main/set.h | 94 ++++++++++++++
> src/mesa/sources.mak | 1 +
> 4 files changed, 445 insertions(+)
> create mode 100644 src/mesa/main/set.c
> create mode 100644 src/mesa/main/set.h
>
> diff --git a/src/mesa/SConscript b/src/mesa/SConscript
> index 1afa412..a2492f7 100644
> --- a/src/mesa/SConscript
> +++ b/src/mesa/SConscript
> @@ -107,6 +107,7 @@ main_sources = [
> 'main/renderbuffer.c',
> 'main/samplerobj.c',
> 'main/scissor.c',
> + 'main/set.c',
> 'main/shaderapi.c',
> 'main/shaderobj.c',
> 'main/shader_query.cpp',
> diff --git a/src/mesa/main/set.c b/src/mesa/main/set.c
> new file mode 100644
> index 0000000..c530c40
> --- /dev/null
> +++ b/src/mesa/main/set.c
> @@ -0,0 +1,349 @@
> +/*
> + * Copyright © 2009-2012 Intel Corporation
> + * Copyright © 1988-2004 Keith Packard and Bart Massey.
> + *
> + * 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, sublicense,
> + * 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 NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS 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.
> + *
> + * Except as contained in this notice, the names of the authors
> + * or their institutions shall not be used in advertising or
> + * otherwise to promote the sale, use or other dealings in this
> + * Software without prior written authorization from the
> + * authors.
> + *
> + * Authors:
> + * Eric Anholt<eric at anholt.net>
> + * Keith Packard<keithp at keithp.com>
> + */
> +
> +#include<stdlib.h>
> +
> +#include "set.h"
> +#include "ralloc.h"
> +
> +#define ARRAY_SIZE(array) (sizeof(array) / sizeof(array[0]))
> +
> +/*
> + * From Knuth -- a good choice for hash/rehash values is p, p-2 where
> + * p and p-2 are both prime. These tables are sized to have an extra 10%
> + * free to avoid exponential performance degradation as the hash table fills
> + */
> +
> +uint32_t deleted_key_value;
> +const void *deleted_key =&deleted_key_value;
> +
> +static const struct {
> + uint32_t max_entries, size, rehash;
> +} hash_sizes[] = {
> + { 2, 5, 3 },
> + { 4, 7, 5 },
> + { 8, 13, 11 },
> + { 16, 19, 17 },
> + { 32, 43, 41 },
> + { 64, 73, 71 },
> + { 128, 151, 149 },
> + { 256, 283, 281 },
> + { 512, 571, 569 },
> + { 1024, 1153, 1151 },
> + { 2048, 2269, 2267 },
> + { 4096, 4519, 4517 },
> + { 8192, 9013, 9011 },
> + { 16384, 18043, 18041 },
> + { 32768, 36109, 36107 },
> + { 65536, 72091, 72089 },
> + { 131072, 144409, 144407 },
> + { 262144, 288361, 288359 },
> + { 524288, 576883, 576881 },
> + { 1048576, 1153459, 1153457 },
> + { 2097152, 2307163, 2307161 },
> + { 4194304, 4613893, 4613891 },
> + { 8388608, 9227641, 9227639 },
> + { 16777216, 18455029, 18455027 },
> + { 33554432, 36911011, 36911009 },
> + { 67108864, 73819861, 73819859 },
> + { 134217728, 147639589, 147639587 },
> + { 268435456, 295279081, 295279079 },
> + { 536870912, 590559793, 590559791 },
> + { 1073741824, 1181116273, 1181116271 },
> + { 2147483648ul, 2362232233ul, 2362232231ul }
> +};
> +
> +static int
> +entry_is_free(struct set_entry *entry)
> +{
> + return entry->key == NULL;
> +}
> +
> +static int
> +entry_is_deleted(struct set_entry *entry)
> +{
> + return entry->key == deleted_key;
> +}
> +
> +static int
> +entry_is_present(struct set_entry *entry)
> +{
> + return entry->key != NULL&& entry->key != deleted_key;
> +}
> +
> +struct set *
> +_mesa_set_create(void *mem_ctx,
> + bool key_equals_function(const void *a,
> + const void *b))
> +{
> + struct set *ht;
> +
> + ht = ralloc(mem_ctx, struct set);
> + if (ht == NULL)
> + return NULL;
> +
> + ht->mem_ctx = mem_ctx;
> + ht->size_index = 0;
> + ht->size = hash_sizes[ht->size_index].size;
> + ht->rehash = hash_sizes[ht->size_index].rehash;
> + ht->max_entries = hash_sizes[ht->size_index].max_entries;
> + ht->key_equals_function = key_equals_function;
> + ht->table = rzalloc_array(ht, struct set_entry, ht->size);
> + ht->entries = 0;
> + ht->deleted_entries = 0;
> +
> + if (ht->table == NULL) {
> + ralloc_free(ht);
> + return NULL;
> + }
> +
> + return ht;
> +}
> +
> +/**
> + * Frees the given set.
> + *
> + * If delete_function is passed, it gets called on each entry present before
> + * freeing.
> + */
> +void
> +_mesa_set_destroy(struct set *ht, void (*delete_function)(struct set_entry *entry))
> +{
> + if (!ht)
> + return;
> +
> + if (delete_function) {
> + struct set_entry *entry;
> +
> + set_foreach (ht, entry) {
> + delete_function(entry);
> + }
> + }
> + ralloc_free(ht->table);
> + ralloc_free(ht);
> +}
> +
> +/**
> + * Finds a set entry with the given key and hash of that key.
> + *
> + * Returns NULL if no entry is found.
> + */
> +struct set_entry *
> +_mesa_set_search(struct set *ht, uint32_t hash, const void *key)
I think 'ht' could be const-qualified here.
> +{
> + uint32_t hash_address;
> +
> + hash_address = hash % ht->size;
> + do {
> + uint32_t double_hash;
> +
> + struct set_entry *entry = ht->table + hash_address;
> +
> + if (entry_is_free(entry)) {
> + return NULL;
> + } else if (entry_is_present(entry)&& entry->hash == hash) {
> + if (ht->key_equals_function(key, entry->key)) {
> + return entry;
> + }
> + }
> +
> + double_hash = 1 + hash % ht->rehash;
> +
> + hash_address = (hash_address + double_hash) % ht->size;
> + } while (hash_address != hash % ht->size);
> +
> + return NULL;
> +}
> +
> +static void
> +set_rehash(struct set *ht, int new_size_index)
> +{
> + struct set old_ht;
> + struct set_entry *table, *entry;
> +
> + if (new_size_index>= ARRAY_SIZE(hash_sizes))
> + return;
> +
> + table = rzalloc_array(ht, struct set_entry,
> + hash_sizes[new_size_index].size);
> + if (table == NULL)
> + return;
> +
> + old_ht = *ht;
> +
> + ht->table = table;
> + ht->size_index = new_size_index;
> + ht->size = hash_sizes[ht->size_index].size;
> + ht->rehash = hash_sizes[ht->size_index].rehash;
> + ht->max_entries = hash_sizes[ht->size_index].max_entries;
> + ht->entries = 0;
> + ht->deleted_entries = 0;
> +
> + for (entry = old_ht.table;
> + entry != old_ht.table + old_ht.size;
> + entry++) {
> + if (entry_is_present(entry)) {
> + _mesa_set_add(ht, entry->hash, entry->key);
> + }
> + }
> +
> + ralloc_free(old_ht.table);
> +}
> +
> +/**
> + * Inserts the key with the given hash into the table.
> + *
> + * Note that insertion may rearrange the table on a resize or rehash,
> + * so previously found hash_entries are no longer valid after this function.
> + */
> +struct set_entry *
> +_mesa_set_add(struct set *ht, uint32_t hash, const void *key)
> +{
> + uint32_t hash_address;
> +
> + if (ht->entries>= ht->max_entries) {
> + set_rehash(ht, ht->size_index + 1);
> + } else if (ht->deleted_entries + ht->entries>= ht->max_entries) {
> + set_rehash(ht, ht->size_index);
> + }
> +
> + hash_address = hash % ht->size;
> + do {
> + struct set_entry *entry = ht->table + hash_address;
> + uint32_t double_hash;
> +
> + if (!entry_is_present(entry)) {
> + if (entry_is_deleted(entry))
> + ht->deleted_entries--;
> + entry->hash = hash;
> + entry->key = key;
> + ht->entries++;
> + return entry;
> + }
> +
> + /* Implement replacement when another insert happens
> + * with a matching key. This is a relatively common
> + * feature of hash tables, with the alternative
> + * generally being "insert the new value as well, and
> + * return it first when the key is searched for".
> + *
> + * Note that the hash table doesn't have a delete callback.
> + * If freeing of old keys is required to avoid memory leaks,
> + * perform a search before inserting.
> + */
> + if (entry->hash == hash&&
> + ht->key_equals_function(key, entry->key)) {
> + entry->key = key;
> + return entry;
> + }
> +
> +
Double blank lines there.
> + double_hash = 1 + hash % ht->rehash;
> +
> + hash_address = (hash_address + double_hash) % ht->size;
> + } while (hash_address != hash % ht->size);
> +
> + /* We could hit here if a required resize failed. An unchecked-malloc
> + * application could ignore this result.
> + */
> + return NULL;
> +}
> +
> +/**
> + * This function deletes the given hash table entry.
> + *
> + * Note that deletion doesn't otherwise modify the table, so an iteration over
> + * the table deleting entries is safe.
> + */
> +void
> +_mesa_set_remove(struct set *ht, struct set_entry *entry)
> +{
> + if (!entry)
> + return;
> +
> + entry->key = deleted_key;
> + ht->entries--;
> + ht->deleted_entries++;
> +}
> +
> +/**
> + * This function is an iterator over the hash table.
> + *
> + * Pass in NULL for the first entry, as in the start of a for loop. Note that
> + * an iteration over the table is O(table_size) not O(entries).
> + */
> +struct set_entry *
> +_mesa_set_next_entry(struct set *ht, struct set_entry *entry)
Should ht be const-qualified here too?
> +{
> + if (entry == NULL)
> + entry = ht->table;
> + else
> + entry = entry + 1;
> +
> + for (; entry != ht->table + ht->size; entry++) {
> + if (entry_is_present(entry)) {
> + return entry;
> + }
> + }
> +
> + return NULL;
> +}
> +
> +struct set_entry *
> +_mesa_set_random_entry(struct set *ht,
> + int (*predicate)(struct set_entry *entry))
> +{
> + struct set_entry *entry;
> + uint32_t i = random() % ht->size;
> +
> + if (ht->entries == 0)
> + return NULL;
> +
> + for (entry = ht->table + i; entry != ht->table + ht->size; entry++) {
> + if (entry_is_present(entry)&&
> + (!predicate || predicate(entry))) {
> + return entry;
> + }
> + }
> +
> + for (entry = ht->table; entry != ht->table + i; entry++) {
> + if (entry_is_present(entry)&&
> + (!predicate || predicate(entry))) {
> + return entry;
> + }
> + }
> +
> + return NULL;
> +}
> +
> diff --git a/src/mesa/main/set.h b/src/mesa/main/set.h
> new file mode 100644
> index 0000000..520ca4a
> --- /dev/null
> +++ b/src/mesa/main/set.h
> @@ -0,0 +1,94 @@
> +/*
> + * Copyright © 2009-2012 Intel Corporation
> + *
> + * 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, sublicense,
> + * 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 NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS 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:
> + * Eric Anholt<eric at anholt.net>
> + *
> + */
> +
> +#ifndef _SET_H
> +#define _SET_H
> +
> +#include<inttypes.h>
> +#include<stdbool.h>
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
> +struct set_entry {
> + uint32_t hash;
> + const void *key;
> +};
> +
> +struct set {
> + void *mem_ctx;
> + struct set_entry *table;
> + bool (*key_equals_function)(const void *a, const void *b);
> + uint32_t size;
> + uint32_t rehash;
> + uint32_t max_entries;
> + uint32_t size_index;
> + uint32_t entries;
> + uint32_t deleted_entries;
> +};
> +
> +struct set *
> +_mesa_set_create(void *mem_ctx,
> + bool (*key_equals_function)(const void *a,
> + const void *b));
> +void
> +_mesa_set_destroy(struct set *set,
> + void (*delete_function)(struct set_entry *entry));
> +
> +struct set_entry *
> +_mesa_set_add(struct set *set, uint32_t hash, const void *key);
> +
> +struct set_entry *
> +_mesa_set_search(struct set *set, uint32_t hash,
> + const void *key);
> +
> +void
> +_mesa_set_remove(struct set *set, struct set_entry *entry);
> +
> +struct set_entry *
> +_mesa_set_next_entry(struct set *set, struct set_entry *entry);
> +
> +struct set_entry *
> +_mesa_set_random_entry(struct set *set,
> + int (*predicate)(struct set_entry *entry));
> +
> +/**
> + * This foreach function is safe against deletion, but not against
> + * insertion (which may rehash the set, making entry a dangling
> + * pointer).
> + */
> +#define set_foreach(set, entry) \
> + for (entry = _mesa_set_next_entry(set, NULL); \
> + entry != NULL; \
> + entry = _mesa_set_next_entry(set, entry))
> +
> +#ifdef __cplusplus
> +} /* extern C */
> +#endif
> +
> +#endif /* _SET_H */
> diff --git a/src/mesa/sources.mak b/src/mesa/sources.mak
> index d6c8996..8cde2c4 100644
> --- a/src/mesa/sources.mak
> +++ b/src/mesa/sources.mak
> @@ -76,6 +76,7 @@ MAIN_FILES = \
> $(SRCDIR)main/renderbuffer.c \
> $(SRCDIR)main/samplerobj.c \
> $(SRCDIR)main/scissor.c \
> + $(SRCDIR)main/set.c \
> $(SRCDIR)main/shaderapi.c \
> $(SRCDIR)main/shaderobj.c \
> $(SRCDIR)main/shader_query.cpp \
Looks good otherwise.
Reviewed-by: Brian Paul <brianp at vmware.com>
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