Less code, and gives a small speedup due to avoiding the extra modulo operation. Also less memory footprint since rehash gets dropped.
Results from oprofile on a shader-db run: set_add 2.80 ---> 2.70 set_search 2.86 ---> 2.74 runtime 162 ---> 165 --- src/util/set.c | 81 +++++++++++++++++++++++++++------------------------------- src/util/set.h | 1 - 2 files changed, 38 insertions(+), 44 deletions(-) diff --git a/src/util/set.c b/src/util/set.c index f01f869..f350c1e 100644 --- a/src/util/set.c +++ b/src/util/set.c @@ -49,39 +49,39 @@ uint32_t deleted_key_value; const void *deleted_key = &deleted_key_value; static const struct { - uint32_t max_entries, size, rehash; + uint32_t max_entries, size; } 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 } + { 2, 5 }, + { 4, 7 }, + { 8, 13 }, + { 16, 19 }, + { 32, 43 }, + { 64, 73 }, + { 128, 151 }, + { 256, 283 }, + { 512, 571 }, + { 1024, 1153 }, + { 2048, 2269 }, + { 4096, 4519 }, + { 8192, 9013 }, + { 16384, 18043 }, + { 32768, 36109 }, + { 65536, 72091 }, + { 131072, 144409 }, + { 262144, 288361 }, + { 524288, 576883 }, + { 1048576, 1153459 }, + { 2097152, 2307163 }, + { 4194304, 4613893 }, + { 8388608, 9227641 }, + { 16777216, 18455029 }, + { 33554432, 36911011 }, + { 67108864, 73819861 }, + { 134217728, 147639589 }, + { 268435456, 295279081 }, + { 536870912, 590559793 }, + { 1073741824, 1181116273 }, + { 2147483648ul, 2362232233ul } }; static int @@ -116,7 +116,6 @@ _mesa_set_create(void *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_hash_function = key_hash_function; ht->key_equals_function = key_equals_function; @@ -164,11 +163,11 @@ static struct set_entry * set_search(const struct set *ht, uint32_t hash, const void *key) { uint32_t hash_address; + uint32_t quad_hash; + quad_hash = 1; hash_address = hash % ht->size; do { - uint32_t double_hash; - struct set_entry *entry = ht->table + hash_address; if (entry_is_free(entry)) { @@ -179,9 +178,7 @@ set_search(const struct set *ht, uint32_t hash, const void *key) } } - double_hash = 1 + hash % ht->rehash; - - hash_address = (hash_address + double_hash) % ht->size; + hash_address = (hash_address + quad_hash*quad_hash) % ht->size; } while (hash_address != hash % ht->size); return NULL; @@ -225,7 +222,6 @@ set_rehash(struct set *ht, unsigned new_size_index) 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; @@ -251,6 +247,7 @@ static struct set_entry * set_add(struct set *ht, uint32_t hash, const void *key) { uint32_t hash_address; + uint32_t quad_hash; struct set_entry *available_entry = NULL; if (ht->entries >= ht->max_entries) { @@ -259,10 +256,10 @@ set_add(struct set *ht, uint32_t hash, const void *key) set_rehash(ht, ht->size_index); } + quad_hash = 1; hash_address = hash % ht->size; do { struct set_entry *entry = ht->table + hash_address; - uint32_t double_hash; if (!entry_is_present(entry)) { /* Stash the first available entry we find */ @@ -288,9 +285,7 @@ set_add(struct set *ht, uint32_t hash, const void *key) return entry; } - double_hash = 1 + hash % ht->rehash; - - hash_address = (hash_address + double_hash) % ht->size; + hash_address = (hash_address + quad_hash*quad_hash) % ht->size; } while (hash_address != hash % ht->size); if (available_entry) { diff --git a/src/util/set.h b/src/util/set.h index 9acd2c2..5a1097c 100644 --- a/src/util/set.h +++ b/src/util/set.h @@ -46,7 +46,6 @@ struct set { uint32_t (*key_hash_function)(const void *key); 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; -- 2.2.1 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev