[Mesa-dev] [PATCH 1/3] mesa: add set support (stores a set of pointers)
Ian Romanick
idr at freedesktop.org
Wed Dec 5 11:26:11 PST 2012
On 12/05/2012 07:32 AM, Brian Paul wrote:
> 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?
Since the returned set_entry isn't const-qualified, probably not. I
think the compiler will generate an error.
>> +{
>> + 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>
> _______________________________________________
> mesa-dev mailing list
> mesa-dev at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/mesa-dev
>
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