Skip to content
Navigation Menu
{{ message }}
forked from adafruit/circuitpython
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathmap.c
More file actions
461 lines (426 loc) · 17.1 KB
/
Copy pathmap.c
File metadata and controls
461 lines (426 loc) · 17.1 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
*
* 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 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.
*/
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "py/mpconfig.h"
#include "py/misc.h"
#include "py/runtime.h"
#if MICROPY_DEBUG_VERBOSE // print debugging info
#define DEBUG_PRINT (1)
#else // don't print debugging info
#define DEBUG_PRINT (0)
#define DEBUG_printf(...) (void)0
#endif
#if MICROPY_OPT_MAP_LOOKUP_CACHE
// MP_STATE_VM(map_lookup_cache) provides a cache of index to the last known
// position of that index in any map. On a cache hit, this allows
// short-circuiting the full linear search in the case of an ordered map
// (i.e. all builtin modules and objects' locals dicts), and computation of
// the hash (and potentially some linear probing) in the case of a regular
// map. Note the same cache is shared across all maps.
// Gets the index into the cache for this index. Shift down by two to remove
// mp_obj_t tag bits.
#define MAP_CACHE_OFFSET(index) ((((uintptr_t)(index)) >> 2) % MICROPY_OPT_MAP_LOOKUP_CACHE_SIZE)
// Gets the map cache entry for the corresponding index.
#define MAP_CACHE_ENTRY(index) (MP_STATE_VM(map_lookup_cache)[MAP_CACHE_OFFSET(index)])
// Retrieve the mp_obj_t at the location suggested by the cache.
#define MAP_CACHE_GET(map, index) (&(map)->table[MAP_CACHE_ENTRY(index) % (map)->alloc])
// Update the cache for this index.
#define MAP_CACHE_SET(index, pos) MAP_CACHE_ENTRY(index) = (pos) & 0xff;
#else
#define MAP_CACHE_SET(index, pos)
#endif
// This table of sizes is used to control the growth of hash tables.
// The first set of sizes are chosen so the allocation fits exactly in a
// 4-word GC block, and it's not so important for these small values to be
// prime. The latter sizes are prime and increase at an increasing rate.
static const uint16_t hash_allocation_sizes[] = {
0, 2, 4, 6, 8, 10, 12, // +2
17, 23, 29, 37, 47, 59, 73, // *1.25
97, 127, 167, 223, 293, 389, 521, 691, 919, 1223, 1627, 2161, // *1.33
3229, 4831, 7243, 10861, 16273, 24407, 36607, 54907, // *1.5
};
static size_t get_hash_alloc_greater_or_equal_to(size_t x) {
for (size_t i = 0; i < MP_ARRAY_SIZE(hash_allocation_sizes); i++) {
if (hash_allocation_sizes[i] >= x) {
return hash_allocation_sizes[i];
}
}
// ran out of primes in the table!
// return something sensible, at least make it odd
return (x + x / 2) | 1;
}
/******************************************************************************/
/* map */
void mp_map_init(mp_map_t *map, size_t n) {
if (n == 0) {
map->alloc = 0;
map->table = NULL;
} else {
map->alloc = n;
map->table = m_new0(mp_map_elem_t, map->alloc);
}
map->used = 0;
map->all_keys_are_qstrs = 1;
map->is_fixed = 0;
map->is_ordered = 0;
}
void mp_map_init_fixed_table(mp_map_t *map, size_t n, const mp_obj_t *table) {
map->alloc = n;
map->used = n;
map->all_keys_are_qstrs = 1;
map->is_fixed = 1;
map->is_ordered = 1;
map->table = (mp_map_elem_t *)table;
}
// Differentiate from mp_map_clear() - semantics is different
void mp_map_deinit(mp_map_t *map) {
if (!map->is_fixed) {
m_del(mp_map_elem_t, map->table, map->alloc);
}
map->used = map->alloc = 0;
}
void mp_map_clear(mp_map_t *map) {
if (!map->is_fixed) {
m_del(mp_map_elem_t, map->table, map->alloc);
}
map->alloc = 0;
map->used = 0;
map->all_keys_are_qstrs = 1;
map->is_fixed = 0;
map->table = NULL;
}
static void mp_map_rehash(mp_map_t *map) {
size_t old_alloc = map->alloc;
size_t new_alloc = get_hash_alloc_greater_or_equal_to(map->alloc + 1);
DEBUG_printf("mp_map_rehash(%p): " UINT_FMT " -> " UINT_FMT "\n", map, old_alloc, new_alloc);
mp_map_elem_t *old_table = map->table;
mp_map_elem_t *new_table = m_new0(mp_map_elem_t, new_alloc);
// If we reach this point, table resizing succeeded, now we can edit the old map.
map->alloc = new_alloc;
map->used = 0;
map->all_keys_are_qstrs = 1;
map->table = new_table;
for (size_t i = 0; i < old_alloc; i++) {
if (old_table[i].key != MP_OBJ_NULL && old_table[i].key != MP_OBJ_SENTINEL) {
mp_map_lookup(map, old_table[i].key, MP_MAP_LOOKUP_ADD_IF_NOT_FOUND)->value = old_table[i].value;
}
}
m_del(mp_map_elem_t, old_table, old_alloc);
}
// MP_MAP_LOOKUP behaviour:
// - returns NULL if not found, else the slot it was found in with key,value non-null
// MP_MAP_LOOKUP_ADD_IF_NOT_FOUND behaviour:
// - returns slot, with key non-null and value=MP_OBJ_NULL if it was added
// MP_MAP_LOOKUP_REMOVE_IF_FOUND behaviour:
// - returns NULL if not found, else the slot if was found in with key null and value non-null
mp_map_elem_t *MICROPY_WRAP_MP_MAP_LOOKUP(mp_map_lookup)(mp_map_t * map, mp_obj_t index, mp_map_lookup_kind_t lookup_kind) {
// If the map is a fixed array then we must only be called for a lookup
assert(!map->is_fixed || lookup_kind == MP_MAP_LOOKUP);
#if MICROPY_OPT_MAP_LOOKUP_CACHE
// Try the cache for lookup or add-if-not-found.
if (lookup_kind != MP_MAP_LOOKUP_REMOVE_IF_FOUND && map->alloc) {
mp_map_elem_t *slot = MAP_CACHE_GET(map, index);
// Note: Just comparing key for value equality will have false negatives, but
// these will be handled by the regular path below.
if (slot->key == index) {
return slot;
}
}
#endif
// Work out if we can compare just pointers
bool compare_only_ptrs = map->all_keys_are_qstrs;
if (compare_only_ptrs) {
if (mp_obj_is_qstr(index)) {
// Index is a qstr, so can just do ptr comparison.
} else if (mp_obj_is_exact_type(index, &mp_type_str)) {
// Index is a non-interned string.
// We can either intern the string, or force a full equality comparison.
// We chose the latter, since interning costs time and potentially RAM,
// and it won't necessarily benefit subsequent calls because these calls
// most likely won't pass the newly-interned string.
compare_only_ptrs = false;
} else if (lookup_kind != MP_MAP_LOOKUP_ADD_IF_NOT_FOUND) {
// If we are not adding, then we can return straight away a failed
// lookup because we know that the index will never be found.
return NULL;
}
}
// if the map is an ordered array then we must do a brute force linear search
if (map->is_ordered) {
for (mp_map_elem_t *elem = &map->table[0], *top = &map->table[map->used]; elem < top; elem++) {
if (elem->key == index || (!compare_only_ptrs && mp_obj_equal(elem->key, index))) {
#if MICROPY_PY_COLLECTIONS_ORDEREDDICT
if (MP_UNLIKELY(lookup_kind == MP_MAP_LOOKUP_REMOVE_IF_FOUND)) {
// remove the found element by moving the rest of the array down
mp_obj_t value = elem->value;
--map->used;
memmove(elem, elem + 1, (top - elem - 1) * sizeof(*elem));
// put the found element after the end so the caller can access it if needed
// note: caller must NULL the value so the GC can clean up (e.g. see dict_get_helper).
elem = &map->table[map->used];
elem->key = MP_OBJ_NULL;
elem->value = value;
}
#endif
MAP_CACHE_SET(index, elem - map->table);
return elem;
}
}
#if MICROPY_PY_COLLECTIONS_ORDEREDDICT
if (MP_LIKELY(lookup_kind != MP_MAP_LOOKUP_ADD_IF_NOT_FOUND)) {
return NULL;
}
if (map->used == map->alloc) {
// TODO: Alloc policy
map->alloc += 4;
map->table = m_renew(mp_map_elem_t, map->table, map->used, map->alloc);
mp_seq_clear(map->table, map->used, map->alloc, sizeof(*map->table));
}
mp_map_elem_t *elem = map->table + map->used++;
elem->key = index;
elem->value = MP_OBJ_NULL;
if (!mp_obj_is_qstr(index)) {
map->all_keys_are_qstrs = 0;
}
return elem;
#else
return NULL;
#endif
}
// map is a hash table (not an ordered array), so do a hash lookup
if (map->alloc == 0) {
if (lookup_kind == MP_MAP_LOOKUP_ADD_IF_NOT_FOUND) {
mp_map_rehash(map);
} else {
return NULL;
}
}
// get hash of index, with fast path for common case of qstr
mp_uint_t hash;
if (mp_obj_is_qstr(index)) {
hash = qstr_hash(MP_OBJ_QSTR_VALUE(index));
} else {
hash = MP_OBJ_SMALL_INT_VALUE(mp_unary_op(MP_UNARY_OP_HASH, index));
}
size_t pos = hash % map->alloc;
size_t start_pos = pos;
mp_map_elem_t *avail_slot = NULL;
for (;;) {
mp_map_elem_t *slot = &map->table[pos];
if (slot->key == MP_OBJ_NULL) {
// found NULL slot, so index is not in table
if (lookup_kind == MP_MAP_LOOKUP_ADD_IF_NOT_FOUND) {
map->used += 1;
if (avail_slot == NULL) {
avail_slot = slot;
}
avail_slot->key = index;
avail_slot->value = MP_OBJ_NULL;
if (!mp_obj_is_qstr(index)) {
map->all_keys_are_qstrs = 0;
}
return avail_slot;
} else {
return NULL;
}
} else if (slot->key == MP_OBJ_SENTINEL) {
// found deleted slot, remember for later
if (avail_slot == NULL) {
avail_slot = slot;
}
} else if (slot->key == index || (!compare_only_ptrs && mp_obj_equal(slot->key, index))) {
// found index
// Note: CPython does not replace the index; try x={True:'true'};x[1]='one';x
if (lookup_kind == MP_MAP_LOOKUP_REMOVE_IF_FOUND) {
// delete element in this slot
map->used--;
if (map->table[(pos + 1) % map->alloc].key == MP_OBJ_NULL) {
// optimisation if next slot is empty
slot->key = MP_OBJ_NULL;
} else {
slot->key = MP_OBJ_SENTINEL;
}
// keep slot->value so that caller can access it if needed
}
MAP_CACHE_SET(index, pos);
return slot;
}
// not yet found, keep searching in this table
pos = (pos + 1) % map->alloc;
if (pos == start_pos) {
// search got back to starting position, so index is not in table
if (lookup_kind == MP_MAP_LOOKUP_ADD_IF_NOT_FOUND) {
if (avail_slot != NULL) {
// there was an available slot, so use that
map->used++;
avail_slot->key = index;
avail_slot->value = MP_OBJ_NULL;
if (!mp_obj_is_qstr(index)) {
map->all_keys_are_qstrs = 0;
}
return avail_slot;
} else {
// not enough room in table, rehash it
mp_map_rehash(map);
// restart the search for the new element
start_pos = pos = hash % map->alloc;
}
} else {
return NULL;
}
}
}
}
/******************************************************************************/
/* set */
#if MICROPY_PY_BUILTINS_SET
void mp_set_init(mp_set_t *set, size_t n) {
set->alloc = n;
set->used = 0;
set->table = m_new0(mp_obj_t, set->alloc);
}
static void mp_set_rehash(mp_set_t *set) {
size_t old_alloc = set->alloc;
mp_obj_t *old_table = set->table;
set->alloc = get_hash_alloc_greater_or_equal_to(set->alloc + 1);
set->used = 0;
set->table = m_new0(mp_obj_t, set->alloc);
for (size_t i = 0; i < old_alloc; i++) {
if (old_table[i] != MP_OBJ_NULL && old_table[i] != MP_OBJ_SENTINEL) {
mp_set_lookup(set, old_table[i], MP_MAP_LOOKUP_ADD_IF_NOT_FOUND);
}
}
m_del(mp_obj_t, old_table, old_alloc);
}
mp_obj_t mp_set_lookup(mp_set_t *set, mp_obj_t index, mp_map_lookup_kind_t lookup_kind) {
// Note: lookup_kind can be MP_MAP_LOOKUP_ADD_IF_NOT_FOUND_OR_REMOVE_IF_FOUND which
// is handled by using bitwise operations.
if (set->alloc == 0) {
if (lookup_kind & MP_MAP_LOOKUP_ADD_IF_NOT_FOUND) {
mp_set_rehash(set);
} else {
return MP_OBJ_NULL;
}
}
mp_uint_t hash = MP_OBJ_SMALL_INT_VALUE(mp_unary_op(MP_UNARY_OP_HASH, index));
size_t pos = hash % set->alloc;
size_t start_pos = pos;
mp_obj_t *avail_slot = NULL;
for (;;) {
mp_obj_t elem = set->table[pos];
if (elem == MP_OBJ_NULL) {
// found NULL slot, so index is not in table
if (lookup_kind & MP_MAP_LOOKUP_ADD_IF_NOT_FOUND) {
if (avail_slot == NULL) {
avail_slot = &set->table[pos];
}
set->used++;
*avail_slot = index;
return index;
} else {
return MP_OBJ_NULL;
}
} else if (elem == MP_OBJ_SENTINEL) {
// found deleted slot, remember for later
if (avail_slot == NULL) {
avail_slot = &set->table[pos];
}
} else if (mp_obj_equal(elem, index)) {
// found index
if (lookup_kind & MP_MAP_LOOKUP_REMOVE_IF_FOUND) {
// delete element
set->used--;
if (set->table[(pos + 1) % set->alloc] == MP_OBJ_NULL) {
// optimisation if next slot is empty
set->table[pos] = MP_OBJ_NULL;
} else {
set->table[pos] = MP_OBJ_SENTINEL;
}
}
return elem;
}
// not yet found, keep searching in this table
pos = (pos + 1) % set->alloc;
if (pos == start_pos) {
// search got back to starting position, so index is not in table
if (lookup_kind & MP_MAP_LOOKUP_ADD_IF_NOT_FOUND) {
if (avail_slot != NULL) {
// there was an available slot, so use that
set->used++;
*avail_slot = index;
return index;
} else {
// not enough room in table, rehash it
mp_set_rehash(set);
// restart the search for the new element
start_pos = pos = hash % set->alloc;
}
} else {
return MP_OBJ_NULL;
}
}
}
}
mp_obj_t mp_set_remove_first(mp_set_t *set) {
for (size_t pos = 0; pos < set->alloc; pos++) {
if (mp_set_slot_is_filled(set, pos)) {
mp_obj_t elem = set->table[pos];
// delete element
set->used--;
if (set->table[(pos + 1) % set->alloc] == MP_OBJ_NULL) {
// optimisation if next slot is empty
set->table[pos] = MP_OBJ_NULL;
} else {
set->table[pos] = MP_OBJ_SENTINEL;
}
return elem;
}
}
return MP_OBJ_NULL;
}
void mp_set_clear(mp_set_t *set) {
m_del(mp_obj_t, set->table, set->alloc);
set->alloc = 0;
set->used = 0;
set->table = NULL;
}
#endif // MICROPY_PY_BUILTINS_SET
#if defined(DEBUG_PRINT) && DEBUG_PRINT
void mp_map_dump(mp_map_t *map) {
for (size_t i = 0; i < map->alloc; i++) {
if (map->table[i].key != MP_OBJ_NULL) {
mp_obj_print(map->table[i].key, PRINT_REPR);
} else {
DEBUG_printf("(nil)");
}
DEBUG_printf(": %p\n", map->table[i].value);
}
DEBUG_printf("---\n");
}
#endif
You can’t perform that action at this time.