1 /*
2 * Copyright © 2009,2012 Intel Corporation
3 * Copyright © 1988-2004 Keith Packard and Bart Massey.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the next
13 * paragraph) shall be included in all copies or substantial portions of the
14 * Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 *
24 * Except as contained in this notice, the names of the authors
25 * or their institutions shall not be used in advertising or
26 * otherwise to promote the sale, use or other dealings in this
27 * Software without prior written authorization from the
28 * authors.
29 *
30 * Authors:
31 * Eric Anholt <eric@anholt.net>
32 * Keith Packard <keithp@keithp.com>
33 */
34
35 /**
36 * Implements an open-addressing, linear-reprobing hash table.
37 *
38 * For more information, see:
39 *
40 * http://cgit.freedesktop.org/~anholt/hash_table/tree/README
41 */
42
43 #include <stdlib.h>
44 #include <string.h>
45 #include <assert.h>
46
47 #include "hash_table.h"
48 #include "ralloc.h"
49 #include "macros.h"
50 #include "u_memory.h"
51 #include "fast_urem_by_const.h"
52 #include "util/u_memory.h"
53
54 #define XXH_INLINE_ALL
55 #include "xxhash.h"
56
57 /**
58 * Magic number that gets stored outside of the struct hash_table.
59 *
60 * The hash table needs a particular pointer to be the marker for a key that
61 * was deleted from the table, along with NULL for the "never allocated in the
62 * table" marker. Legacy GL allows any GLuint to be used as a GL object name,
63 * and we use a 1:1 mapping from GLuints to key pointers, so we need to be
64 * able to track a GLuint that happens to match the deleted key outside of
65 * struct hash_table. We tell the hash table to use "1" as the deleted key
66 * value, so that we test the deleted-key-in-the-table path as best we can.
67 */
68 #define DELETED_KEY_VALUE 1
69
70 static inline void *
uint_key(unsigned id)71 uint_key(unsigned id)
72 {
73 return (void *)(uintptr_t) id;
74 }
75
76 static const uint32_t deleted_key_value;
77
78 /**
79 * From Knuth -- a good choice for hash/rehash values is p, p-2 where
80 * p and p-2 are both prime. These tables are sized to have an extra 10%
81 * free to avoid exponential performance degradation as the hash table fills
82 */
83 static const struct {
84 uint32_t max_entries, size, rehash;
85 uint64_t size_magic, rehash_magic;
86 } hash_sizes[] = {
87 #define ENTRY(max_entries, size, rehash) \
88 { max_entries, size, rehash, \
89 REMAINDER_MAGIC(size), REMAINDER_MAGIC(rehash) }
90
91 ENTRY(2, 5, 3 ),
92 ENTRY(4, 7, 5 ),
93 ENTRY(8, 13, 11 ),
94 ENTRY(16, 19, 17 ),
95 ENTRY(32, 43, 41 ),
96 ENTRY(64, 73, 71 ),
97 ENTRY(128, 151, 149 ),
98 ENTRY(256, 283, 281 ),
99 ENTRY(512, 571, 569 ),
100 ENTRY(1024, 1153, 1151 ),
101 ENTRY(2048, 2269, 2267 ),
102 ENTRY(4096, 4519, 4517 ),
103 ENTRY(8192, 9013, 9011 ),
104 ENTRY(16384, 18043, 18041 ),
105 ENTRY(32768, 36109, 36107 ),
106 ENTRY(65536, 72091, 72089 ),
107 ENTRY(131072, 144409, 144407 ),
108 ENTRY(262144, 288361, 288359 ),
109 ENTRY(524288, 576883, 576881 ),
110 ENTRY(1048576, 1153459, 1153457 ),
111 ENTRY(2097152, 2307163, 2307161 ),
112 ENTRY(4194304, 4613893, 4613891 ),
113 ENTRY(8388608, 9227641, 9227639 ),
114 ENTRY(16777216, 18455029, 18455027 ),
115 ENTRY(33554432, 36911011, 36911009 ),
116 ENTRY(67108864, 73819861, 73819859 ),
117 ENTRY(134217728, 147639589, 147639587 ),
118 ENTRY(268435456, 295279081, 295279079 ),
119 ENTRY(536870912, 590559793, 590559791 ),
120 ENTRY(1073741824, 1181116273, 1181116271 ),
121 ENTRY(2147483648ul, 2362232233ul, 2362232231ul )
122 };
123
124 ASSERTED static inline bool
key_pointer_is_reserved(const struct hash_table * ht,const void * key)125 key_pointer_is_reserved(const struct hash_table *ht, const void *key)
126 {
127 return key == NULL || key == ht->deleted_key;
128 }
129
130 static int
entry_is_free(const struct hash_entry * entry)131 entry_is_free(const struct hash_entry *entry)
132 {
133 return entry->key == NULL;
134 }
135
136 static int
entry_is_deleted(const struct hash_table * ht,struct hash_entry * entry)137 entry_is_deleted(const struct hash_table *ht, struct hash_entry *entry)
138 {
139 return entry->key == ht->deleted_key;
140 }
141
142 static int
entry_is_present(const struct hash_table * ht,struct hash_entry * entry)143 entry_is_present(const struct hash_table *ht, struct hash_entry *entry)
144 {
145 return entry->key != NULL && entry->key != ht->deleted_key;
146 }
147
148 bool
_mesa_hash_table_init(struct hash_table * ht,void * mem_ctx,uint32_t (* key_hash_function)(const void * key),bool (* key_equals_function)(const void * a,const void * b))149 _mesa_hash_table_init(struct hash_table *ht,
150 void *mem_ctx,
151 uint32_t (*key_hash_function)(const void *key),
152 bool (*key_equals_function)(const void *a,
153 const void *b))
154 {
155 ht->size_index = 0;
156 ht->size = hash_sizes[ht->size_index].size;
157 ht->rehash = hash_sizes[ht->size_index].rehash;
158 ht->size_magic = hash_sizes[ht->size_index].size_magic;
159 ht->rehash_magic = hash_sizes[ht->size_index].rehash_magic;
160 ht->max_entries = hash_sizes[ht->size_index].max_entries;
161 ht->key_hash_function = key_hash_function;
162 ht->key_equals_function = key_equals_function;
163 ht->table = rzalloc_array(mem_ctx, struct hash_entry, ht->size);
164 ht->entries = 0;
165 ht->deleted_entries = 0;
166 ht->deleted_key = &deleted_key_value;
167
168 return ht->table != NULL;
169 }
170
171 struct hash_table *
_mesa_hash_table_create(void * mem_ctx,uint32_t (* key_hash_function)(const void * key),bool (* key_equals_function)(const void * a,const void * b))172 _mesa_hash_table_create(void *mem_ctx,
173 uint32_t (*key_hash_function)(const void *key),
174 bool (*key_equals_function)(const void *a,
175 const void *b))
176 {
177 struct hash_table *ht;
178
179 /* mem_ctx is used to allocate the hash table, but the hash table is used
180 * to allocate all of the suballocations.
181 */
182 ht = ralloc(mem_ctx, struct hash_table);
183 if (ht == NULL)
184 return NULL;
185
186 if (!_mesa_hash_table_init(ht, ht, key_hash_function, key_equals_function)) {
187 ralloc_free(ht);
188 return NULL;
189 }
190
191 return ht;
192 }
193
194 static uint32_t
key_u32_hash(const void * key)195 key_u32_hash(const void *key)
196 {
197 uint32_t u = (uint32_t)(uintptr_t)key;
198 return _mesa_hash_uint(&u);
199 }
200
201 static bool
key_u32_equals(const void * a,const void * b)202 key_u32_equals(const void *a, const void *b)
203 {
204 return (uint32_t)(uintptr_t)a == (uint32_t)(uintptr_t)b;
205 }
206
207 /* key == 0 and key == deleted_key are not allowed */
208 struct hash_table *
_mesa_hash_table_create_u32_keys(void * mem_ctx)209 _mesa_hash_table_create_u32_keys(void *mem_ctx)
210 {
211 return _mesa_hash_table_create(mem_ctx, key_u32_hash, key_u32_equals);
212 }
213
214 struct hash_table *
_mesa_hash_table_clone(struct hash_table * src,void * dst_mem_ctx)215 _mesa_hash_table_clone(struct hash_table *src, void *dst_mem_ctx)
216 {
217 struct hash_table *ht;
218
219 ht = ralloc(dst_mem_ctx, struct hash_table);
220 if (ht == NULL)
221 return NULL;
222
223 memcpy(ht, src, sizeof(struct hash_table));
224
225 ht->table = ralloc_array(ht, struct hash_entry, ht->size);
226 if (ht->table == NULL) {
227 ralloc_free(ht);
228 return NULL;
229 }
230
231 memcpy(ht->table, src->table, ht->size * sizeof(struct hash_entry));
232
233 return ht;
234 }
235
236 /**
237 * Frees the given hash table.
238 *
239 * If delete_function is passed, it gets called on each entry present before
240 * freeing.
241 */
242 void
_mesa_hash_table_destroy(struct hash_table * ht,void (* delete_function)(struct hash_entry * entry))243 _mesa_hash_table_destroy(struct hash_table *ht,
244 void (*delete_function)(struct hash_entry *entry))
245 {
246 if (!ht)
247 return;
248
249 if (delete_function) {
250 hash_table_foreach(ht, entry) {
251 delete_function(entry);
252 }
253 }
254 ralloc_free(ht);
255 }
256
257 static void
hash_table_clear_fast(struct hash_table * ht)258 hash_table_clear_fast(struct hash_table *ht)
259 {
260 memset(ht->table, 0, sizeof(struct hash_entry) * hash_sizes[ht->size_index].size);
261 ht->entries = ht->deleted_entries = 0;
262 }
263
264 /**
265 * Deletes all entries of the given hash table without deleting the table
266 * itself or changing its structure.
267 *
268 * If delete_function is passed, it gets called on each entry present.
269 */
270 void
_mesa_hash_table_clear(struct hash_table * ht,void (* delete_function)(struct hash_entry * entry))271 _mesa_hash_table_clear(struct hash_table *ht,
272 void (*delete_function)(struct hash_entry *entry))
273 {
274 if (!ht)
275 return;
276
277 struct hash_entry *entry;
278
279 if (delete_function) {
280 for (entry = ht->table; entry != ht->table + ht->size; entry++) {
281 if (entry_is_present(ht, entry))
282 delete_function(entry);
283
284 entry->key = NULL;
285 }
286 ht->entries = 0;
287 ht->deleted_entries = 0;
288 } else
289 hash_table_clear_fast(ht);
290 }
291
292 /** Sets the value of the key pointer used for deleted entries in the table.
293 *
294 * The assumption is that usually keys are actual pointers, so we use a
295 * default value of a pointer to an arbitrary piece of storage in the library.
296 * But in some cases a consumer wants to store some other sort of value in the
297 * table, like a uint32_t, in which case that pointer may conflict with one of
298 * their valid keys. This lets that user select a safe value.
299 *
300 * This must be called before any keys are actually deleted from the table.
301 */
302 void
_mesa_hash_table_set_deleted_key(struct hash_table * ht,const void * deleted_key)303 _mesa_hash_table_set_deleted_key(struct hash_table *ht, const void *deleted_key)
304 {
305 ht->deleted_key = deleted_key;
306 }
307
308 static struct hash_entry *
hash_table_search(struct hash_table * ht,uint32_t hash,const void * key)309 hash_table_search(struct hash_table *ht, uint32_t hash, const void *key)
310 {
311 assert(!key_pointer_is_reserved(ht, key));
312
313 uint32_t size = ht->size;
314 uint32_t start_hash_address = util_fast_urem32(hash, size, ht->size_magic);
315 uint32_t double_hash = 1 + util_fast_urem32(hash, ht->rehash,
316 ht->rehash_magic);
317 uint32_t hash_address = start_hash_address;
318
319 do {
320 struct hash_entry *entry = ht->table + hash_address;
321
322 if (entry_is_free(entry)) {
323 return NULL;
324 } else if (entry_is_present(ht, entry) && entry->hash == hash) {
325 if (ht->key_equals_function(key, entry->key)) {
326 return entry;
327 }
328 }
329
330 hash_address += double_hash;
331 if (hash_address >= size)
332 hash_address -= size;
333 } while (hash_address != start_hash_address);
334
335 return NULL;
336 }
337
338 /**
339 * Finds a hash table entry with the given key and hash of that key.
340 *
341 * Returns NULL if no entry is found. Note that the data pointer may be
342 * modified by the user.
343 */
344 struct hash_entry *
_mesa_hash_table_search(struct hash_table * ht,const void * key)345 _mesa_hash_table_search(struct hash_table *ht, const void *key)
346 {
347 assert(ht->key_hash_function);
348 return hash_table_search(ht, ht->key_hash_function(key), key);
349 }
350
351 struct hash_entry *
_mesa_hash_table_search_pre_hashed(struct hash_table * ht,uint32_t hash,const void * key)352 _mesa_hash_table_search_pre_hashed(struct hash_table *ht, uint32_t hash,
353 const void *key)
354 {
355 assert(ht->key_hash_function == NULL || hash == ht->key_hash_function(key));
356 return hash_table_search(ht, hash, key);
357 }
358
359 static struct hash_entry *
360 hash_table_insert(struct hash_table *ht, uint32_t hash,
361 const void *key, void *data);
362
363 static void
hash_table_insert_rehash(struct hash_table * ht,uint32_t hash,const void * key,void * data)364 hash_table_insert_rehash(struct hash_table *ht, uint32_t hash,
365 const void *key, void *data)
366 {
367 uint32_t size = ht->size;
368 uint32_t start_hash_address = util_fast_urem32(hash, size, ht->size_magic);
369 uint32_t double_hash = 1 + util_fast_urem32(hash, ht->rehash,
370 ht->rehash_magic);
371 uint32_t hash_address = start_hash_address;
372 do {
373 struct hash_entry *entry = ht->table + hash_address;
374
375 if (likely(entry->key == NULL)) {
376 entry->hash = hash;
377 entry->key = key;
378 entry->data = data;
379 return;
380 }
381
382 hash_address += double_hash;
383 if (hash_address >= size)
384 hash_address -= size;
385 } while (true);
386 }
387
388 static void
_mesa_hash_table_rehash(struct hash_table * ht,unsigned new_size_index)389 _mesa_hash_table_rehash(struct hash_table *ht, unsigned new_size_index)
390 {
391 struct hash_table old_ht;
392 struct hash_entry *table;
393
394 if (ht->size_index == new_size_index && ht->deleted_entries == ht->max_entries) {
395 hash_table_clear_fast(ht);
396 assert(!ht->entries);
397 return;
398 }
399
400 if (new_size_index >= ARRAY_SIZE(hash_sizes))
401 return;
402
403 table = rzalloc_array(ralloc_parent(ht->table), struct hash_entry,
404 hash_sizes[new_size_index].size);
405 if (table == NULL)
406 return;
407
408 old_ht = *ht;
409
410 ht->table = table;
411 ht->size_index = new_size_index;
412 ht->size = hash_sizes[ht->size_index].size;
413 ht->rehash = hash_sizes[ht->size_index].rehash;
414 ht->size_magic = hash_sizes[ht->size_index].size_magic;
415 ht->rehash_magic = hash_sizes[ht->size_index].rehash_magic;
416 ht->max_entries = hash_sizes[ht->size_index].max_entries;
417 ht->entries = 0;
418 ht->deleted_entries = 0;
419
420 hash_table_foreach(&old_ht, entry) {
421 hash_table_insert_rehash(ht, entry->hash, entry->key, entry->data);
422 }
423
424 ht->entries = old_ht.entries;
425
426 ralloc_free(old_ht.table);
427 }
428
429 static struct hash_entry *
hash_table_insert(struct hash_table * ht,uint32_t hash,const void * key,void * data)430 hash_table_insert(struct hash_table *ht, uint32_t hash,
431 const void *key, void *data)
432 {
433 struct hash_entry *available_entry = NULL;
434
435 assert(!key_pointer_is_reserved(ht, key));
436
437 if (ht->entries >= ht->max_entries) {
438 _mesa_hash_table_rehash(ht, ht->size_index + 1);
439 } else if (ht->deleted_entries + ht->entries >= ht->max_entries) {
440 _mesa_hash_table_rehash(ht, ht->size_index);
441 }
442
443 uint32_t size = ht->size;
444 uint32_t start_hash_address = util_fast_urem32(hash, size, ht->size_magic);
445 uint32_t double_hash = 1 + util_fast_urem32(hash, ht->rehash,
446 ht->rehash_magic);
447 uint32_t hash_address = start_hash_address;
448 do {
449 struct hash_entry *entry = ht->table + hash_address;
450
451 if (!entry_is_present(ht, entry)) {
452 /* Stash the first available entry we find */
453 if (available_entry == NULL)
454 available_entry = entry;
455 if (entry_is_free(entry))
456 break;
457 }
458
459 /* Implement replacement when another insert happens
460 * with a matching key. This is a relatively common
461 * feature of hash tables, with the alternative
462 * generally being "insert the new value as well, and
463 * return it first when the key is searched for".
464 *
465 * Note that the hash table doesn't have a delete
466 * callback. If freeing of old data pointers is
467 * required to avoid memory leaks, perform a search
468 * before inserting.
469 */
470 if (!entry_is_deleted(ht, entry) &&
471 entry->hash == hash &&
472 ht->key_equals_function(key, entry->key)) {
473 entry->key = key;
474 entry->data = data;
475 return entry;
476 }
477
478 hash_address += double_hash;
479 if (hash_address >= size)
480 hash_address -= size;
481 } while (hash_address != start_hash_address);
482
483 if (available_entry) {
484 if (entry_is_deleted(ht, available_entry))
485 ht->deleted_entries--;
486 available_entry->hash = hash;
487 available_entry->key = key;
488 available_entry->data = data;
489 ht->entries++;
490 return available_entry;
491 }
492
493 /* We could hit here if a required resize failed. An unchecked-malloc
494 * application could ignore this result.
495 */
496 return NULL;
497 }
498
499 /**
500 * Inserts the key with the given hash into the table.
501 *
502 * Note that insertion may rearrange the table on a resize or rehash,
503 * so previously found hash_entries are no longer valid after this function.
504 */
505 struct hash_entry *
_mesa_hash_table_insert(struct hash_table * ht,const void * key,void * data)506 _mesa_hash_table_insert(struct hash_table *ht, const void *key, void *data)
507 {
508 assert(ht->key_hash_function);
509 return hash_table_insert(ht, ht->key_hash_function(key), key, data);
510 }
511
512 struct hash_entry *
_mesa_hash_table_insert_pre_hashed(struct hash_table * ht,uint32_t hash,const void * key,void * data)513 _mesa_hash_table_insert_pre_hashed(struct hash_table *ht, uint32_t hash,
514 const void *key, void *data)
515 {
516 assert(ht->key_hash_function == NULL || hash == ht->key_hash_function(key));
517 return hash_table_insert(ht, hash, key, data);
518 }
519
520 /**
521 * This function deletes the given hash table entry.
522 *
523 * Note that deletion doesn't otherwise modify the table, so an iteration over
524 * the table deleting entries is safe.
525 */
526 void
_mesa_hash_table_remove(struct hash_table * ht,struct hash_entry * entry)527 _mesa_hash_table_remove(struct hash_table *ht,
528 struct hash_entry *entry)
529 {
530 if (!entry)
531 return;
532
533 entry->key = ht->deleted_key;
534 ht->entries--;
535 ht->deleted_entries++;
536 }
537
538 /**
539 * Removes the entry with the corresponding key, if exists.
540 */
_mesa_hash_table_remove_key(struct hash_table * ht,const void * key)541 void _mesa_hash_table_remove_key(struct hash_table *ht,
542 const void *key)
543 {
544 _mesa_hash_table_remove(ht, _mesa_hash_table_search(ht, key));
545 }
546
547 /**
548 * This function is an iterator over the hash_table when no deleted entries are present.
549 *
550 * Pass in NULL for the first entry, as in the start of a for loop.
551 */
552 struct hash_entry *
_mesa_hash_table_next_entry_unsafe(const struct hash_table * ht,struct hash_entry * entry)553 _mesa_hash_table_next_entry_unsafe(const struct hash_table *ht, struct hash_entry *entry)
554 {
555 assert(!ht->deleted_entries);
556 if (!ht->entries)
557 return NULL;
558 if (entry == NULL)
559 entry = ht->table;
560 else
561 entry = entry + 1;
562 if (entry != ht->table + ht->size)
563 return entry->key ? entry : _mesa_hash_table_next_entry_unsafe(ht, entry);
564
565 return NULL;
566 }
567
568 /**
569 * This function is an iterator over the hash table.
570 *
571 * Pass in NULL for the first entry, as in the start of a for loop. Note that
572 * an iteration over the table is O(table_size) not O(entries).
573 */
574 struct hash_entry *
_mesa_hash_table_next_entry(struct hash_table * ht,struct hash_entry * entry)575 _mesa_hash_table_next_entry(struct hash_table *ht,
576 struct hash_entry *entry)
577 {
578 if (entry == NULL)
579 entry = ht->table;
580 else
581 entry = entry + 1;
582
583 for (; entry != ht->table + ht->size; entry++) {
584 if (entry_is_present(ht, entry)) {
585 return entry;
586 }
587 }
588
589 return NULL;
590 }
591
592 /**
593 * Returns a random entry from the hash table.
594 *
595 * This may be useful in implementing random replacement (as opposed
596 * to just removing everything) in caches based on this hash table
597 * implementation. @predicate may be used to filter entries, or may
598 * be set to NULL for no filtering.
599 */
600 struct hash_entry *
_mesa_hash_table_random_entry(struct hash_table * ht,bool (* predicate)(struct hash_entry * entry))601 _mesa_hash_table_random_entry(struct hash_table *ht,
602 bool (*predicate)(struct hash_entry *entry))
603 {
604 struct hash_entry *entry;
605 uint32_t i = rand() % ht->size;
606
607 if (ht->entries == 0)
608 return NULL;
609
610 for (entry = ht->table + i; entry != ht->table + ht->size; entry++) {
611 if (entry_is_present(ht, entry) &&
612 (!predicate || predicate(entry))) {
613 return entry;
614 }
615 }
616
617 for (entry = ht->table; entry != ht->table + i; entry++) {
618 if (entry_is_present(ht, entry) &&
619 (!predicate || predicate(entry))) {
620 return entry;
621 }
622 }
623
624 return NULL;
625 }
626
627
628 uint32_t
_mesa_hash_data(const void * data,size_t size)629 _mesa_hash_data(const void *data, size_t size)
630 {
631 return XXH32(data, size, 0);
632 }
633
634 uint32_t
_mesa_hash_data_with_seed(const void * data,size_t size,uint32_t seed)635 _mesa_hash_data_with_seed(const void *data, size_t size, uint32_t seed)
636 {
637 return XXH32(data, size, seed);
638 }
639
640 uint32_t
_mesa_hash_int(const void * key)641 _mesa_hash_int(const void *key)
642 {
643 return XXH32(key, sizeof(int), 0);
644 }
645
646 uint32_t
_mesa_hash_uint(const void * key)647 _mesa_hash_uint(const void *key)
648 {
649 return XXH32(key, sizeof(unsigned), 0);
650 }
651
652 uint32_t
_mesa_hash_u32(const void * key)653 _mesa_hash_u32(const void *key)
654 {
655 return XXH32(key, 4, 0);
656 }
657
658 /** FNV-1a string hash implementation */
659 uint32_t
_mesa_hash_string(const void * _key)660 _mesa_hash_string(const void *_key)
661 {
662 return _mesa_hash_string_with_length(_key, strlen((const char *)_key));
663 }
664
665 uint32_t
_mesa_hash_string_with_length(const void * _key,unsigned length)666 _mesa_hash_string_with_length(const void *_key, unsigned length)
667 {
668 uint32_t hash = 0;
669 const char *key = _key;
670 #if defined(_WIN64) || defined(__x86_64__)
671 hash = (uint32_t)XXH64(key, length, hash);
672 #else
673 hash = XXH32(key, length, hash);
674 #endif
675 return hash;
676 }
677
678 uint32_t
_mesa_hash_pointer(const void * pointer)679 _mesa_hash_pointer(const void *pointer)
680 {
681 uintptr_t num = (uintptr_t) pointer;
682 return (uint32_t) ((num >> 2) ^ (num >> 6) ^ (num >> 10) ^ (num >> 14));
683 }
684
685 bool
_mesa_key_int_equal(const void * a,const void * b)686 _mesa_key_int_equal(const void *a, const void *b)
687 {
688 return *((const int *)a) == *((const int *)b);
689 }
690
691 bool
_mesa_key_uint_equal(const void * a,const void * b)692 _mesa_key_uint_equal(const void *a, const void *b)
693 {
694
695 return *((const unsigned *)a) == *((const unsigned *)b);
696 }
697
698 bool
_mesa_key_u32_equal(const void * a,const void * b)699 _mesa_key_u32_equal(const void *a, const void *b)
700 {
701 return *((const uint32_t *)a) == *((const uint32_t *)b);
702 }
703
704 /**
705 * String compare function for use as the comparison callback in
706 * _mesa_hash_table_create().
707 */
708 bool
_mesa_key_string_equal(const void * a,const void * b)709 _mesa_key_string_equal(const void *a, const void *b)
710 {
711 return strcmp(a, b) == 0;
712 }
713
714 bool
_mesa_key_pointer_equal(const void * a,const void * b)715 _mesa_key_pointer_equal(const void *a, const void *b)
716 {
717 return a == b;
718 }
719
720 /**
721 * Helper to create a hash table with pointer keys.
722 */
723 struct hash_table *
_mesa_pointer_hash_table_create(void * mem_ctx)724 _mesa_pointer_hash_table_create(void *mem_ctx)
725 {
726 return _mesa_hash_table_create(mem_ctx, _mesa_hash_pointer,
727 _mesa_key_pointer_equal);
728 }
729
730
731 bool
_mesa_hash_table_reserve(struct hash_table * ht,unsigned size)732 _mesa_hash_table_reserve(struct hash_table *ht, unsigned size)
733 {
734 if (size < ht->max_entries)
735 return true;
736 for (unsigned i = ht->size_index + 1; i < ARRAY_SIZE(hash_sizes); i++) {
737 if (hash_sizes[i].max_entries >= size) {
738 _mesa_hash_table_rehash(ht, i);
739 break;
740 }
741 }
742 return ht->max_entries >= size;
743 }
744
745 /**
746 * Hash table wrapper which supports 64-bit keys.
747 *
748 * TODO: unify all hash table implementations.
749 */
750
751 struct hash_key_u64 {
752 uint64_t value;
753 };
754
755 static uint32_t
key_u64_hash(const void * key)756 key_u64_hash(const void *key)
757 {
758 return _mesa_hash_data(key, sizeof(struct hash_key_u64));
759 }
760
761 static bool
key_u64_equals(const void * a,const void * b)762 key_u64_equals(const void *a, const void *b)
763 {
764 const struct hash_key_u64 *aa = a;
765 const struct hash_key_u64 *bb = b;
766
767 return aa->value == bb->value;
768 }
769
770 #define FREED_KEY_VALUE 0
771
772 struct hash_table_u64 *
_mesa_hash_table_u64_create(void * mem_ctx)773 _mesa_hash_table_u64_create(void *mem_ctx)
774 {
775 STATIC_ASSERT(FREED_KEY_VALUE != DELETED_KEY_VALUE);
776 struct hash_table_u64 *ht;
777
778 ht = CALLOC_STRUCT(hash_table_u64);
779 if (!ht)
780 return NULL;
781
782 if (sizeof(void *) == 8) {
783 ht->table = _mesa_hash_table_create(mem_ctx, _mesa_hash_pointer,
784 _mesa_key_pointer_equal);
785 } else {
786 ht->table = _mesa_hash_table_create(mem_ctx, key_u64_hash,
787 key_u64_equals);
788 }
789
790 if (ht->table)
791 _mesa_hash_table_set_deleted_key(ht->table, uint_key(DELETED_KEY_VALUE));
792
793 return ht;
794 }
795
796 static void
_mesa_hash_table_u64_delete_key(struct hash_entry * entry)797 _mesa_hash_table_u64_delete_key(struct hash_entry *entry)
798 {
799 if (sizeof(void *) == 8)
800 return;
801
802 struct hash_key_u64 *_key = (struct hash_key_u64 *)entry->key;
803
804 if (_key)
805 free(_key);
806 }
807
808 void
_mesa_hash_table_u64_clear(struct hash_table_u64 * ht)809 _mesa_hash_table_u64_clear(struct hash_table_u64 *ht)
810 {
811 if (!ht)
812 return;
813
814 _mesa_hash_table_clear(ht->table, _mesa_hash_table_u64_delete_key);
815 ht->freed_key_data = NULL;
816 ht->deleted_key_data = NULL;
817 }
818
819 void
_mesa_hash_table_u64_destroy(struct hash_table_u64 * ht)820 _mesa_hash_table_u64_destroy(struct hash_table_u64 *ht)
821 {
822 if (!ht)
823 return;
824
825 _mesa_hash_table_u64_clear(ht);
826 _mesa_hash_table_destroy(ht->table, NULL);
827 free(ht);
828 }
829
830 void
_mesa_hash_table_u64_insert(struct hash_table_u64 * ht,uint64_t key,void * data)831 _mesa_hash_table_u64_insert(struct hash_table_u64 *ht, uint64_t key,
832 void *data)
833 {
834 if (key == FREED_KEY_VALUE) {
835 ht->freed_key_data = data;
836 return;
837 }
838
839 if (key == DELETED_KEY_VALUE) {
840 ht->deleted_key_data = data;
841 return;
842 }
843
844 if (sizeof(void *) == 8) {
845 _mesa_hash_table_insert(ht->table, (void *)(uintptr_t)key, data);
846 } else {
847 struct hash_key_u64 *_key = CALLOC_STRUCT(hash_key_u64);
848
849 if (!_key)
850 return;
851 _key->value = key;
852
853 _mesa_hash_table_insert(ht->table, _key, data);
854 }
855 }
856
857 static struct hash_entry *
hash_table_u64_search(struct hash_table_u64 * ht,uint64_t key)858 hash_table_u64_search(struct hash_table_u64 *ht, uint64_t key)
859 {
860 if (sizeof(void *) == 8) {
861 return _mesa_hash_table_search(ht->table, (void *)(uintptr_t)key);
862 } else {
863 struct hash_key_u64 _key = { .value = key };
864 return _mesa_hash_table_search(ht->table, &_key);
865 }
866 }
867
868 void *
_mesa_hash_table_u64_search(struct hash_table_u64 * ht,uint64_t key)869 _mesa_hash_table_u64_search(struct hash_table_u64 *ht, uint64_t key)
870 {
871 struct hash_entry *entry;
872
873 if (key == FREED_KEY_VALUE)
874 return ht->freed_key_data;
875
876 if (key == DELETED_KEY_VALUE)
877 return ht->deleted_key_data;
878
879 entry = hash_table_u64_search(ht, key);
880 if (!entry)
881 return NULL;
882
883 return entry->data;
884 }
885
886 void
_mesa_hash_table_u64_remove(struct hash_table_u64 * ht,uint64_t key)887 _mesa_hash_table_u64_remove(struct hash_table_u64 *ht, uint64_t key)
888 {
889 struct hash_entry *entry;
890
891 if (key == FREED_KEY_VALUE) {
892 ht->freed_key_data = NULL;
893 return;
894 }
895
896 if (key == DELETED_KEY_VALUE) {
897 ht->deleted_key_data = NULL;
898 return;
899 }
900
901 entry = hash_table_u64_search(ht, key);
902 if (!entry)
903 return;
904
905 if (sizeof(void *) == 8) {
906 _mesa_hash_table_remove(ht->table, entry);
907 } else {
908 struct hash_key *_key = (struct hash_key *)entry->key;
909
910 _mesa_hash_table_remove(ht->table, entry);
911 free(_key);
912 }
913 }
914