Mercurial > hg > xemacs-beta
annotate src/elhash.c @ 5117:3742ea8250b5 ben-lisp-object ben-lisp-object-final-ws-year-2005
Checking in final CVS version of workspace 'ben-lisp-object'
| author | Ben Wing <ben@xemacs.org> |
|---|---|
| date | Sat, 26 Dec 2009 00:20:27 -0600 |
| parents | 1e7cc382eb16 |
| children | e0db3c197671 |
| rev | line source |
|---|---|
| 428 | 1 /* Implementation of the hash table lisp object type. |
| 2 Copyright (C) 1992, 1993, 1994 Free Software Foundation, Inc. | |
| 2421 | 3 Copyright (C) 1995, 1996, 2002, 2004 Ben Wing. |
| 428 | 4 Copyright (C) 1997 Free Software Foundation, Inc. |
| 5 | |
| 6 This file is part of XEmacs. | |
| 7 | |
| 8 XEmacs is free software; you can redistribute it and/or modify it | |
| 9 under the terms of the GNU General Public License as published by the | |
| 10 Free Software Foundation; either version 2, or (at your option) any | |
| 11 later version. | |
| 12 | |
| 13 XEmacs is distributed in the hope that it will be useful, but WITHOUT | |
| 14 ANY WARRANTY; without even the implied warranty of MERCNTABILITY or | |
| 15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 16 for more details. | |
| 17 | |
| 18 You should have received a copy of the GNU General Public License | |
| 19 along with XEmacs; see the file COPYING. If not, write to | |
| 20 the Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
| 21 Boston, MA 02111-1307, USA. */ | |
| 22 | |
| 23 /* Synched up with: Not in FSF. */ | |
| 24 | |
| 1292 | 25 /* Author: Lost in the mists of history. At least back to Lucid 19.3, |
| 26 circa Sep 1992. Early hash table implementation allowed only `eq' as a | |
| 27 test -- other tests possible only when these objects were created from | |
| 28 the C code. | |
| 29 | |
| 30 Expansion to allow general `equal'-test Lisp-creatable tables, and hash | |
| 31 methods for the various Lisp objects in existence at the time, added | |
| 32 during 19.12 I think (early 1995?), by Ben Wing. | |
| 33 | |
| 34 Weak hash tables added by Jamie (maybe?) early on, perhaps around 19.6, | |
| 35 maybe earlier; again, only possible through the C code, and only | |
| 36 supported fully weak hash tables. Expansion to other kinds of weakness, | |
| 37 and exporting of the interface to Lisp, by Ben Wing during 19.12 | |
| 38 (early-mid 1995) or maybe 19.13 cycle (mid 1995). | |
| 39 | |
| 40 Expansion to full Common Lisp spec and interface, redoing of the | |
| 41 implementation, by Martin Buchholz, 1997? (Former hash table | |
| 42 implementation used "double hashing", I'm pretty sure, and was weirdly | |
| 43 tied into the generic hash.c code. Martin completely separated them.) | |
| 44 */ | |
| 45 | |
| 489 | 46 /* This file implements the hash table lisp object type. |
| 47 | |
| 504 | 48 This implementation was mostly written by Martin Buchholz in 1997. |
| 49 | |
| 50 The Lisp-level API (derived from Common Lisp) is almost completely | |
| 51 compatible with GNU Emacs 21, even though the implementations are | |
| 52 totally independent. | |
| 53 | |
| 489 | 54 The hash table technique used is "linear probing". Collisions are |
| 55 resolved by putting the item in the next empty place in the array | |
| 56 following the collision. Finding a hash entry performs a linear | |
| 57 search in the cluster starting at the hash value. | |
| 58 | |
| 59 On deletions from the hash table, the entries immediately following | |
| 60 the deleted entry are re-entered in the hash table. We do not have | |
| 61 a special way to mark deleted entries (known as "tombstones"). | |
| 62 | |
| 63 At the end of the hash entries ("hentries"), we leave room for an | |
| 64 entry that is always empty (the "sentinel"). | |
| 65 | |
| 66 The traditional literature on hash table implementation | |
| 67 (e.g. Knuth) suggests that too much "primary clustering" occurs | |
| 68 with linear probing. However, this literature was written when | |
| 69 locality of reference was not a factor. The discrepancy between | |
| 70 CPU speeds and memory speeds is increasing, and the speed of access | |
| 71 to memory is highly dependent on memory caches which work best when | |
| 72 there is high locality of data reference. Random access to memory | |
| 73 is up to 20 times as expensive as access to the nearest address | |
| 74 (and getting worse). So linear probing makes sense. | |
| 75 | |
| 76 But the representation doesn't actually matter that much with the | |
| 77 current elisp engine. Funcall is sufficiently slow that the choice | |
| 78 of hash table implementation is noise. */ | |
| 79 | |
| 428 | 80 #include <config.h> |
| 81 #include "lisp.h" | |
| 82 #include "bytecode.h" | |
| 83 #include "elhash.h" | |
| 489 | 84 #include "opaque.h" |
| 428 | 85 |
| 86 Lisp_Object Qhash_tablep; | |
| 87 static Lisp_Object Qhashtable, Qhash_table; | |
| 442 | 88 static Lisp_Object Qweakness, Qvalue, Qkey_or_value, Qkey_and_value; |
| 428 | 89 static Lisp_Object Vall_weak_hash_tables; |
| 90 static Lisp_Object Qrehash_size, Qrehash_threshold; | |
| 91 static Lisp_Object Q_size, Q_test, Q_weakness, Q_rehash_size, Q_rehash_threshold; | |
| 92 | |
| 93 /* obsolete as of 19990901 in xemacs-21.2 */ | |
| 442 | 94 static Lisp_Object Qweak, Qkey_weak, Qvalue_weak, Qkey_or_value_weak; |
| 95 static Lisp_Object Qnon_weak, Q_type; | |
| 428 | 96 |
| 1204 | 97 typedef struct htentry |
| 428 | 98 { |
| 99 Lisp_Object key; | |
| 100 Lisp_Object value; | |
| 1204 | 101 } htentry; |
| 428 | 102 |
| 103 struct Lisp_Hash_Table | |
| 104 { | |
| 3017 | 105 struct LCRECORD_HEADER header; |
| 665 | 106 Elemcount size; |
| 107 Elemcount count; | |
| 108 Elemcount rehash_count; | |
| 428 | 109 double rehash_size; |
| 110 double rehash_threshold; | |
| 665 | 111 Elemcount golden_ratio; |
| 428 | 112 hash_table_hash_function_t hash_function; |
| 113 hash_table_test_function_t test_function; | |
| 1204 | 114 htentry *hentries; |
| 428 | 115 enum hash_table_weakness weakness; |
| 116 Lisp_Object next_weak; /* Used to chain together all of the weak | |
| 117 hash tables. Don't mark through this. */ | |
| 118 }; | |
| 119 | |
| 1204 | 120 #define HTENTRY_CLEAR_P(htentry) ((*(EMACS_UINT*)(&((htentry)->key))) == 0) |
| 121 #define CLEAR_HTENTRY(htentry) \ | |
| 122 ((*(EMACS_UINT*)(&((htentry)->key))) = 0, \ | |
| 123 (*(EMACS_UINT*)(&((htentry)->value))) = 0) | |
| 428 | 124 |
| 125 #define HASH_TABLE_DEFAULT_SIZE 16 | |
| 126 #define HASH_TABLE_DEFAULT_REHASH_SIZE 1.3 | |
| 127 #define HASH_TABLE_MIN_SIZE 10 | |
| 128 | |
| 665 | 129 #define HASHCODE(key, ht) \ |
| 444 | 130 ((((ht)->hash_function ? (ht)->hash_function (key) : LISP_HASH (key)) \ |
| 131 * (ht)->golden_ratio) \ | |
| 132 % (ht)->size) | |
| 428 | 133 |
| 134 #define KEYS_EQUAL_P(key1, key2, testfun) \ | |
| 434 | 135 (EQ (key1, key2) || ((testfun) && (testfun) (key1, key2))) |
| 428 | 136 |
| 137 #define LINEAR_PROBING_LOOP(probe, entries, size) \ | |
| 138 for (; \ | |
| 1204 | 139 !HTENTRY_CLEAR_P (probe) || \ |
| 428 | 140 (probe == entries + size ? \ |
| 1204 | 141 (probe = entries, !HTENTRY_CLEAR_P (probe)) : 0); \ |
| 428 | 142 probe++) |
| 143 | |
| 800 | 144 #ifdef ERROR_CHECK_STRUCTURES |
| 428 | 145 static void |
| 146 check_hash_table_invariants (Lisp_Hash_Table *ht) | |
| 147 { | |
| 148 assert (ht->count < ht->size); | |
| 149 assert (ht->count <= ht->rehash_count); | |
| 150 assert (ht->rehash_count < ht->size); | |
| 151 assert ((double) ht->count * ht->rehash_threshold - 1 <= (double) ht->rehash_count); | |
| 1204 | 152 assert (HTENTRY_CLEAR_P (ht->hentries + ht->size)); |
| 428 | 153 } |
| 154 #else | |
| 155 #define check_hash_table_invariants(ht) | |
| 156 #endif | |
| 157 | |
| 158 /* Return a suitable size for a hash table, with at least SIZE slots. */ | |
| 665 | 159 static Elemcount |
| 160 hash_table_size (Elemcount requested_size) | |
| 428 | 161 { |
| 162 /* Return some prime near, but greater than or equal to, SIZE. | |
| 163 Decades from the time of writing, someone will have a system large | |
| 164 enough that the list below will be too short... */ | |
| 665 | 165 static const Elemcount primes [] = |
| 428 | 166 { |
| 167 19, 29, 41, 59, 79, 107, 149, 197, 263, 347, 457, 599, 787, 1031, | |
| 168 1361, 1777, 2333, 3037, 3967, 5167, 6719, 8737, 11369, 14783, | |
| 169 19219, 24989, 32491, 42257, 54941, 71429, 92861, 120721, 156941, | |
| 170 204047, 265271, 344857, 448321, 582821, 757693, 985003, 1280519, | |
| 171 1664681, 2164111, 2813353, 3657361, 4754591, 6180989, 8035301, | |
| 172 10445899, 13579681, 17653589, 22949669, 29834603, 38784989, | |
| 173 50420551, 65546729, 85210757, 110774011, 144006217, 187208107, | |
| 174 243370577, 316381771, 411296309, 534685237, 695090819, 903618083, | |
| 647 | 175 1174703521, 1527114613, 1985248999 /* , 2580823717UL, 3355070839UL */ |
| 428 | 176 }; |
| 177 /* We've heard of binary search. */ | |
| 178 int low, high; | |
| 179 for (low = 0, high = countof (primes) - 1; high - low > 1;) | |
| 180 { | |
| 181 /* Loop Invariant: size < primes [high] */ | |
| 182 int mid = (low + high) / 2; | |
| 183 if (primes [mid] < requested_size) | |
| 184 low = mid; | |
| 185 else | |
| 186 high = mid; | |
| 187 } | |
| 188 return primes [high]; | |
| 189 } | |
| 190 | |
| 191 | |
| 192 #if 0 /* I don't think these are needed any more. | |
| 193 If using the general lisp_object_equal_*() functions | |
| 194 causes efficiency problems, these can be resurrected. --ben */ | |
| 195 /* equality and hash functions for Lisp strings */ | |
| 196 int | |
| 197 lisp_string_equal (Lisp_Object str1, Lisp_Object str2) | |
| 198 { | |
| 199 /* This is wrong anyway. You can't use strcmp() on Lisp strings, | |
| 200 because they can contain zero characters. */ | |
| 201 return !strcmp ((char *) XSTRING_DATA (str1), (char *) XSTRING_DATA (str2)); | |
| 202 } | |
| 203 | |
| 665 | 204 static Hashcode |
| 428 | 205 lisp_string_hash (Lisp_Object obj) |
| 206 { | |
| 207 return hash_string (XSTRING_DATA (str), XSTRING_LENGTH (str)); | |
| 208 } | |
| 209 | |
| 210 #endif /* 0 */ | |
| 211 | |
| 212 static int | |
| 213 lisp_object_eql_equal (Lisp_Object obj1, Lisp_Object obj2) | |
| 214 { | |
| 215 return EQ (obj1, obj2) || (FLOATP (obj1) && internal_equal (obj1, obj2, 0)); | |
| 216 } | |
| 217 | |
| 665 | 218 static Hashcode |
| 428 | 219 lisp_object_eql_hash (Lisp_Object obj) |
| 220 { | |
| 221 return FLOATP (obj) ? internal_hash (obj, 0) : LISP_HASH (obj); | |
| 222 } | |
| 223 | |
| 224 static int | |
| 225 lisp_object_equal_equal (Lisp_Object obj1, Lisp_Object obj2) | |
| 226 { | |
| 227 return internal_equal (obj1, obj2, 0); | |
| 228 } | |
| 229 | |
| 665 | 230 static Hashcode |
| 428 | 231 lisp_object_equal_hash (Lisp_Object obj) |
| 232 { | |
| 233 return internal_hash (obj, 0); | |
| 234 } | |
| 235 | |
| 236 | |
| 237 static Lisp_Object | |
| 238 mark_hash_table (Lisp_Object obj) | |
| 239 { | |
| 240 Lisp_Hash_Table *ht = XHASH_TABLE (obj); | |
| 241 | |
| 242 /* If the hash table is weak, we don't want to mark the keys and | |
| 243 values (we scan over them after everything else has been marked, | |
| 244 and mark or remove them as necessary). */ | |
| 245 if (ht->weakness == HASH_TABLE_NON_WEAK) | |
| 246 { | |
| 1204 | 247 htentry *e, *sentinel; |
| 428 | 248 |
| 249 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++) | |
| 1204 | 250 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 251 { |
| 252 mark_object (e->key); | |
| 253 mark_object (e->value); | |
| 254 } | |
| 255 } | |
| 256 return Qnil; | |
| 257 } | |
| 258 | |
| 259 /* Equality of hash tables. Two hash tables are equal when they are of | |
| 260 the same weakness and test function, they have the same number of | |
| 261 elements, and for each key in the hash table, the values are `equal'. | |
| 262 | |
| 263 This is similar to Common Lisp `equalp' of hash tables, with the | |
| 264 difference that CL requires the keys to be compared with the test | |
| 265 function, which we don't do. Doing that would require consing, and | |
| 266 consing is a bad idea in `equal'. Anyway, our method should provide | |
| 267 the same result -- if the keys are not equal according to the test | |
| 268 function, then Fgethash() in hash_table_equal_mapper() will fail. */ | |
| 269 static int | |
| 270 hash_table_equal (Lisp_Object hash_table1, Lisp_Object hash_table2, int depth) | |
| 271 { | |
| 272 Lisp_Hash_Table *ht1 = XHASH_TABLE (hash_table1); | |
| 273 Lisp_Hash_Table *ht2 = XHASH_TABLE (hash_table2); | |
| 1204 | 274 htentry *e, *sentinel; |
| 428 | 275 |
| 276 if ((ht1->test_function != ht2->test_function) || | |
| 277 (ht1->weakness != ht2->weakness) || | |
| 278 (ht1->count != ht2->count)) | |
| 279 return 0; | |
| 280 | |
| 281 depth++; | |
| 282 | |
| 283 for (e = ht1->hentries, sentinel = e + ht1->size; e < sentinel; e++) | |
| 1204 | 284 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 285 /* Look up the key in the other hash table, and compare the values. */ |
| 286 { | |
| 287 Lisp_Object value_in_other = Fgethash (e->key, hash_table2, Qunbound); | |
| 288 if (UNBOUNDP (value_in_other) || | |
| 289 !internal_equal (e->value, value_in_other, depth)) | |
| 290 return 0; /* Give up */ | |
| 291 } | |
| 292 | |
| 293 return 1; | |
| 294 } | |
| 442 | 295 |
| 296 /* This is not a great hash function, but it _is_ correct and fast. | |
| 297 Examining all entries is too expensive, and examining a random | |
| 298 subset does not yield a correct hash function. */ | |
| 665 | 299 static Hashcode |
| 2286 | 300 hash_table_hash (Lisp_Object hash_table, int UNUSED (depth)) |
| 442 | 301 { |
| 302 return XHASH_TABLE (hash_table)->count; | |
| 303 } | |
| 304 | |
| 428 | 305 |
| 306 /* Printing hash tables. | |
| 307 | |
| 308 This is non-trivial, because we use a readable structure-style | |
| 309 syntax for hash tables. This means that a typical hash table will be | |
| 310 readably printed in the form of: | |
| 311 | |
| 312 #s(hash-table size 2 data (key1 value1 key2 value2)) | |
| 313 | |
| 314 The supported hash table structure keywords and their values are: | |
| 315 `test' (eql (or nil), eq or equal) | |
| 316 `size' (a natnum or nil) | |
| 317 `rehash-size' (a float) | |
| 318 `rehash-threshold' (a float) | |
| 442 | 319 `weakness' (nil, key, value, key-and-value, or key-or-value) |
| 428 | 320 `data' (a list) |
| 321 | |
| 430 | 322 If `print-readably' is nil, then a simpler syntax is used, for example |
| 428 | 323 |
| 324 #<hash-table size 2/13 data (key1 value1 key2 value2) 0x874d> | |
| 325 | |
| 326 The data is truncated to four pairs, and the rest is shown with | |
| 327 `...'. This printer does not cons. */ | |
| 328 | |
| 329 | |
| 330 /* Print the data of the hash table. This maps through a Lisp | |
| 331 hash table and prints key/value pairs using PRINTCHARFUN. */ | |
| 332 static void | |
| 333 print_hash_table_data (Lisp_Hash_Table *ht, Lisp_Object printcharfun) | |
| 334 { | |
| 335 int count = 0; | |
| 1204 | 336 htentry *e, *sentinel; |
| 428 | 337 |
| 826 | 338 write_c_string (printcharfun, " data ("); |
| 428 | 339 |
| 340 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++) | |
| 1204 | 341 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 342 { |
| 343 if (count > 0) | |
| 826 | 344 write_c_string (printcharfun, " "); |
| 428 | 345 if (!print_readably && count > 3) |
| 346 { | |
| 826 | 347 write_c_string (printcharfun, "..."); |
| 428 | 348 break; |
| 349 } | |
| 350 print_internal (e->key, printcharfun, 1); | |
| 800 | 351 write_fmt_string_lisp (printcharfun, " %S", 1, e->value); |
| 428 | 352 count++; |
| 353 } | |
| 354 | |
| 826 | 355 write_c_string (printcharfun, ")"); |
| 428 | 356 } |
| 357 | |
| 358 static void | |
| 2286 | 359 print_hash_table (Lisp_Object obj, Lisp_Object printcharfun, |
| 360 int UNUSED (escapeflag)) | |
| 428 | 361 { |
| 362 Lisp_Hash_Table *ht = XHASH_TABLE (obj); | |
| 363 | |
| 826 | 364 write_c_string (printcharfun, |
| 365 print_readably ? "#s(hash-table" : "#<hash-table"); | |
| 428 | 366 |
| 367 /* These checks have a kludgy look to them, but they are safe. | |
| 368 Due to nature of hashing, you cannot use arbitrary | |
| 369 test functions anyway. */ | |
| 370 if (!ht->test_function) | |
| 826 | 371 write_c_string (printcharfun, " test eq"); |
| 428 | 372 else if (ht->test_function == lisp_object_equal_equal) |
| 826 | 373 write_c_string (printcharfun, " test equal"); |
| 428 | 374 else if (ht->test_function == lisp_object_eql_equal) |
| 375 DO_NOTHING; | |
| 376 else | |
| 2500 | 377 ABORT (); |
| 428 | 378 |
| 379 if (ht->count || !print_readably) | |
| 380 { | |
| 381 if (print_readably) | |
| 800 | 382 write_fmt_string (printcharfun, " size %ld", (long) ht->count); |
| 428 | 383 else |
| 800 | 384 write_fmt_string (printcharfun, " size %ld/%ld", (long) ht->count, |
| 385 (long) ht->size); | |
| 428 | 386 } |
| 387 | |
| 388 if (ht->weakness != HASH_TABLE_NON_WEAK) | |
| 389 { | |
| 800 | 390 write_fmt_string |
| 391 (printcharfun, " weakness %s", | |
| 392 (ht->weakness == HASH_TABLE_WEAK ? "key-and-value" : | |
| 393 ht->weakness == HASH_TABLE_KEY_WEAK ? "key" : | |
| 394 ht->weakness == HASH_TABLE_VALUE_WEAK ? "value" : | |
| 395 ht->weakness == HASH_TABLE_KEY_VALUE_WEAK ? "key-or-value" : | |
| 396 "you-d-better-not-see-this")); | |
| 428 | 397 } |
| 398 | |
| 399 if (ht->count) | |
| 400 print_hash_table_data (ht, printcharfun); | |
| 401 | |
| 402 if (print_readably) | |
| 826 | 403 write_c_string (printcharfun, ")"); |
| 428 | 404 else |
| 2421 | 405 write_fmt_string (printcharfun, " 0x%x>", ht->header.uid); |
| 428 | 406 } |
| 407 | |
| 408 static void | |
| 2333 | 409 free_hentries (htentry *hentries, |
| 410 #ifdef ERROR_CHECK_STRUCTURES | |
| 411 size_t size | |
| 412 #else | |
| 413 size_t UNUSED (size) | |
| 414 #endif | |
| 415 ) | |
| 489 | 416 { |
| 800 | 417 #ifdef ERROR_CHECK_STRUCTURES |
| 489 | 418 /* Ensure a crash if other code uses the discarded entries afterwards. */ |
| 1204 | 419 htentry *e, *sentinel; |
| 489 | 420 |
| 421 for (e = hentries, sentinel = e + size; e < sentinel; e++) | |
| 1204 | 422 * (unsigned long *) e = 0xdeadbeef; /* -559038737 base 10 */ |
| 489 | 423 #endif |
| 424 | |
| 425 if (!DUMPEDP (hentries)) | |
| 1726 | 426 xfree (hentries, htentry *); |
| 489 | 427 } |
| 428 | |
| 429 static void | |
| 428 | 430 finalize_hash_table (void *header, int for_disksave) |
| 431 { | |
| 432 if (!for_disksave) | |
| 433 { | |
| 434 Lisp_Hash_Table *ht = (Lisp_Hash_Table *) header; | |
| 489 | 435 free_hentries (ht->hentries, ht->size); |
| 428 | 436 ht->hentries = 0; |
| 437 } | |
| 438 } | |
| 439 | |
| 1204 | 440 static const struct memory_description htentry_description_1[] = { |
| 441 { XD_LISP_OBJECT, offsetof (htentry, key) }, | |
| 442 { XD_LISP_OBJECT, offsetof (htentry, value) }, | |
| 428 | 443 { XD_END } |
| 444 }; | |
| 445 | |
| 1204 | 446 static const struct sized_memory_description htentry_description = { |
| 447 sizeof (htentry), | |
| 448 htentry_description_1 | |
| 428 | 449 }; |
| 450 | |
| 1204 | 451 static const struct memory_description htentry_union_description_1[] = { |
| 452 /* Note: XD_INDIRECT in this table refers to the surrounding table, | |
| 453 and so this will work. */ | |
| 2367 | 454 { XD_BLOCK_PTR, HASH_TABLE_NON_WEAK, XD_INDIRECT (0, 1), |
| 2551 | 455 { &htentry_description } }, |
| 456 { XD_BLOCK_PTR, 0, XD_INDIRECT (0, 1), { &htentry_description }, | |
| 1204 | 457 XD_FLAG_UNION_DEFAULT_ENTRY | XD_FLAG_NO_KKCC }, |
| 458 { XD_END } | |
| 459 }; | |
| 460 | |
| 461 static const struct sized_memory_description htentry_union_description = { | |
| 462 sizeof (htentry *), | |
| 463 htentry_union_description_1 | |
| 464 }; | |
| 465 | |
| 466 const struct memory_description hash_table_description[] = { | |
| 467 { XD_ELEMCOUNT, offsetof (Lisp_Hash_Table, size) }, | |
| 468 { XD_INT, offsetof (Lisp_Hash_Table, weakness) }, | |
| 469 { XD_UNION, offsetof (Lisp_Hash_Table, hentries), XD_INDIRECT (1, 0), | |
| 2551 | 470 { &htentry_union_description } }, |
| 440 | 471 { XD_LO_LINK, offsetof (Lisp_Hash_Table, next_weak) }, |
| 428 | 472 { XD_END } |
| 473 }; | |
| 474 | |
|
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3742ea8250b5
Checking in final CVS version of workspace 'ben-lisp-object'
Ben Wing <ben@xemacs.org>
parents:
3017
diff
changeset
|
475 DEFINE_LISP_OBJECT ("hash-table", hash_table, |
|
3742ea8250b5
Checking in final CVS version of workspace 'ben-lisp-object'
Ben Wing <ben@xemacs.org>
parents:
3017
diff
changeset
|
476 mark_hash_table, print_hash_table, |
| 934 | 477 finalize_hash_table, |
| 478 hash_table_equal, hash_table_hash, | |
| 479 hash_table_description, | |
| 480 Lisp_Hash_Table); | |
| 428 | 481 |
| 482 static Lisp_Hash_Table * | |
| 483 xhash_table (Lisp_Object hash_table) | |
| 484 { | |
| 1123 | 485 /* #### What's going on here? Why the gc_in_progress check? */ |
| 428 | 486 if (!gc_in_progress) |
| 487 CHECK_HASH_TABLE (hash_table); | |
| 488 check_hash_table_invariants (XHASH_TABLE (hash_table)); | |
| 489 return XHASH_TABLE (hash_table); | |
| 490 } | |
| 491 | |
| 492 | |
| 493 /************************************************************************/ | |
| 494 /* Creation of Hash Tables */ | |
| 495 /************************************************************************/ | |
| 496 | |
| 497 /* Creation of hash tables, without error-checking. */ | |
| 498 static void | |
| 499 compute_hash_table_derived_values (Lisp_Hash_Table *ht) | |
| 500 { | |
| 665 | 501 ht->rehash_count = (Elemcount) |
| 438 | 502 ((double) ht->size * ht->rehash_threshold); |
| 665 | 503 ht->golden_ratio = (Elemcount) |
| 428 | 504 ((double) ht->size * (.6180339887 / (double) sizeof (Lisp_Object))); |
| 505 } | |
| 506 | |
| 507 Lisp_Object | |
| 450 | 508 make_standard_lisp_hash_table (enum hash_table_test test, |
| 665 | 509 Elemcount size, |
| 450 | 510 double rehash_size, |
| 511 double rehash_threshold, | |
| 512 enum hash_table_weakness weakness) | |
| 513 { | |
| 462 | 514 hash_table_hash_function_t hash_function = 0; |
| 450 | 515 hash_table_test_function_t test_function = 0; |
| 516 | |
| 517 switch (test) | |
| 518 { | |
| 519 case HASH_TABLE_EQ: | |
| 520 test_function = 0; | |
| 521 hash_function = 0; | |
| 522 break; | |
| 523 | |
| 524 case HASH_TABLE_EQL: | |
| 525 test_function = lisp_object_eql_equal; | |
| 526 hash_function = lisp_object_eql_hash; | |
| 527 break; | |
| 528 | |
| 529 case HASH_TABLE_EQUAL: | |
| 530 test_function = lisp_object_equal_equal; | |
| 531 hash_function = lisp_object_equal_hash; | |
| 532 break; | |
| 533 | |
| 534 default: | |
| 2500 | 535 ABORT (); |
| 450 | 536 } |
| 537 | |
| 538 return make_general_lisp_hash_table (hash_function, test_function, | |
| 539 size, rehash_size, rehash_threshold, | |
| 540 weakness); | |
| 541 } | |
| 542 | |
| 543 Lisp_Object | |
| 544 make_general_lisp_hash_table (hash_table_hash_function_t hash_function, | |
| 545 hash_table_test_function_t test_function, | |
| 665 | 546 Elemcount size, |
| 428 | 547 double rehash_size, |
| 548 double rehash_threshold, | |
| 549 enum hash_table_weakness weakness) | |
| 550 { | |
|
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551 Lisp_Object hash_table = ALLOC_LISP_OBJECT (hash_table); |
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552 Lisp_Hash_Table *ht = XHASH_TABLE (hash_table); |
| 428 | 553 |
| 450 | 554 ht->test_function = test_function; |
| 555 ht->hash_function = hash_function; | |
| 438 | 556 ht->weakness = weakness; |
| 557 | |
| 558 ht->rehash_size = | |
| 559 rehash_size > 1.0 ? rehash_size : HASH_TABLE_DEFAULT_REHASH_SIZE; | |
| 560 | |
| 561 ht->rehash_threshold = | |
| 562 rehash_threshold > 0.0 ? rehash_threshold : | |
| 563 size > 4096 && !ht->test_function ? 0.7 : 0.6; | |
| 564 | |
| 428 | 565 if (size < HASH_TABLE_MIN_SIZE) |
| 566 size = HASH_TABLE_MIN_SIZE; | |
| 665 | 567 ht->size = hash_table_size ((Elemcount) (((double) size / ht->rehash_threshold) |
| 438 | 568 + 1.0)); |
| 428 | 569 ht->count = 0; |
| 438 | 570 |
| 428 | 571 compute_hash_table_derived_values (ht); |
| 572 | |
| 1204 | 573 /* We leave room for one never-occupied sentinel htentry at the end. */ |
| 574 ht->hentries = xnew_array_and_zero (htentry, ht->size + 1); | |
| 428 | 575 |
| 576 if (weakness == HASH_TABLE_NON_WEAK) | |
| 577 ht->next_weak = Qunbound; | |
| 578 else | |
| 579 ht->next_weak = Vall_weak_hash_tables, Vall_weak_hash_tables = hash_table; | |
| 580 | |
| 581 return hash_table; | |
| 582 } | |
| 583 | |
| 584 Lisp_Object | |
| 665 | 585 make_lisp_hash_table (Elemcount size, |
| 428 | 586 enum hash_table_weakness weakness, |
| 587 enum hash_table_test test) | |
| 588 { | |
| 450 | 589 return make_standard_lisp_hash_table (test, size, -1.0, -1.0, weakness); |
| 428 | 590 } |
| 591 | |
| 592 /* Pretty reading of hash tables. | |
| 593 | |
| 594 Here we use the existing structures mechanism (which is, | |
| 595 unfortunately, pretty cumbersome) for validating and instantiating | |
| 596 the hash tables. The idea is that the side-effect of reading a | |
| 597 #s(hash-table PLIST) object is creation of a hash table with desired | |
| 598 properties, and that the hash table is returned. */ | |
| 599 | |
| 600 /* Validation functions: each keyword provides its own validation | |
| 601 function. The errors should maybe be continuable, but it is | |
| 602 unclear how this would cope with ERRB. */ | |
| 603 static int | |
| 2286 | 604 hash_table_size_validate (Lisp_Object UNUSED (keyword), Lisp_Object value, |
| 605 Error_Behavior errb) | |
| 428 | 606 { |
| 607 if (NATNUMP (value)) | |
| 608 return 1; | |
| 609 | |
| 563 | 610 maybe_signal_error_1 (Qwrong_type_argument, list2 (Qnatnump, value), |
| 2286 | 611 Qhash_table, errb); |
| 428 | 612 return 0; |
| 613 } | |
| 614 | |
| 665 | 615 static Elemcount |
| 428 | 616 decode_hash_table_size (Lisp_Object obj) |
| 617 { | |
| 618 return NILP (obj) ? HASH_TABLE_DEFAULT_SIZE : XINT (obj); | |
| 619 } | |
| 620 | |
| 621 static int | |
| 2286 | 622 hash_table_weakness_validate (Lisp_Object UNUSED (keyword), Lisp_Object value, |
| 578 | 623 Error_Behavior errb) |
| 428 | 624 { |
| 442 | 625 if (EQ (value, Qnil)) return 1; |
| 626 if (EQ (value, Qt)) return 1; | |
| 627 if (EQ (value, Qkey)) return 1; | |
| 628 if (EQ (value, Qkey_and_value)) return 1; | |
| 629 if (EQ (value, Qkey_or_value)) return 1; | |
| 630 if (EQ (value, Qvalue)) return 1; | |
| 428 | 631 |
| 632 /* Following values are obsolete as of 19990901 in xemacs-21.2 */ | |
| 442 | 633 if (EQ (value, Qnon_weak)) return 1; |
| 634 if (EQ (value, Qweak)) return 1; | |
| 635 if (EQ (value, Qkey_weak)) return 1; | |
| 636 if (EQ (value, Qkey_or_value_weak)) return 1; | |
| 637 if (EQ (value, Qvalue_weak)) return 1; | |
| 428 | 638 |
| 563 | 639 maybe_invalid_constant ("Invalid hash table weakness", |
| 428 | 640 value, Qhash_table, errb); |
| 641 return 0; | |
| 642 } | |
| 643 | |
| 644 static enum hash_table_weakness | |
| 645 decode_hash_table_weakness (Lisp_Object obj) | |
| 646 { | |
| 442 | 647 if (EQ (obj, Qnil)) return HASH_TABLE_NON_WEAK; |
| 648 if (EQ (obj, Qt)) return HASH_TABLE_WEAK; | |
| 649 if (EQ (obj, Qkey_and_value)) return HASH_TABLE_WEAK; | |
| 650 if (EQ (obj, Qkey)) return HASH_TABLE_KEY_WEAK; | |
| 651 if (EQ (obj, Qkey_or_value)) return HASH_TABLE_KEY_VALUE_WEAK; | |
| 652 if (EQ (obj, Qvalue)) return HASH_TABLE_VALUE_WEAK; | |
| 428 | 653 |
| 654 /* Following values are obsolete as of 19990901 in xemacs-21.2 */ | |
| 442 | 655 if (EQ (obj, Qnon_weak)) return HASH_TABLE_NON_WEAK; |
| 656 if (EQ (obj, Qweak)) return HASH_TABLE_WEAK; | |
| 657 if (EQ (obj, Qkey_weak)) return HASH_TABLE_KEY_WEAK; | |
| 658 if (EQ (obj, Qkey_or_value_weak)) return HASH_TABLE_KEY_VALUE_WEAK; | |
| 659 if (EQ (obj, Qvalue_weak)) return HASH_TABLE_VALUE_WEAK; | |
| 428 | 660 |
| 563 | 661 invalid_constant ("Invalid hash table weakness", obj); |
| 1204 | 662 RETURN_NOT_REACHED (HASH_TABLE_NON_WEAK); |
| 428 | 663 } |
| 664 | |
| 665 static int | |
| 2286 | 666 hash_table_test_validate (Lisp_Object UNUSED (keyword), Lisp_Object value, |
| 667 Error_Behavior errb) | |
| 428 | 668 { |
| 669 if (EQ (value, Qnil)) return 1; | |
| 670 if (EQ (value, Qeq)) return 1; | |
| 671 if (EQ (value, Qequal)) return 1; | |
| 672 if (EQ (value, Qeql)) return 1; | |
| 673 | |
| 563 | 674 maybe_invalid_constant ("Invalid hash table test", |
| 2286 | 675 value, Qhash_table, errb); |
| 428 | 676 return 0; |
| 677 } | |
| 678 | |
| 679 static enum hash_table_test | |
| 680 decode_hash_table_test (Lisp_Object obj) | |
| 681 { | |
| 682 if (EQ (obj, Qnil)) return HASH_TABLE_EQL; | |
| 683 if (EQ (obj, Qeq)) return HASH_TABLE_EQ; | |
| 684 if (EQ (obj, Qequal)) return HASH_TABLE_EQUAL; | |
| 685 if (EQ (obj, Qeql)) return HASH_TABLE_EQL; | |
| 686 | |
| 563 | 687 invalid_constant ("Invalid hash table test", obj); |
| 1204 | 688 RETURN_NOT_REACHED (HASH_TABLE_EQ); |
| 428 | 689 } |
| 690 | |
| 691 static int | |
| 2286 | 692 hash_table_rehash_size_validate (Lisp_Object UNUSED (keyword), |
| 693 Lisp_Object value, Error_Behavior errb) | |
| 428 | 694 { |
| 695 if (!FLOATP (value)) | |
| 696 { | |
| 563 | 697 maybe_signal_error_1 (Qwrong_type_argument, list2 (Qfloatp, value), |
| 428 | 698 Qhash_table, errb); |
| 699 return 0; | |
| 700 } | |
| 701 | |
| 702 { | |
| 703 double rehash_size = XFLOAT_DATA (value); | |
| 704 if (rehash_size <= 1.0) | |
| 705 { | |
| 563 | 706 maybe_invalid_argument |
| 428 | 707 ("Hash table rehash size must be greater than 1.0", |
| 708 value, Qhash_table, errb); | |
| 709 return 0; | |
| 710 } | |
| 711 } | |
| 712 | |
| 713 return 1; | |
| 714 } | |
| 715 | |
| 716 static double | |
| 717 decode_hash_table_rehash_size (Lisp_Object rehash_size) | |
| 718 { | |
| 719 return NILP (rehash_size) ? -1.0 : XFLOAT_DATA (rehash_size); | |
| 720 } | |
| 721 | |
| 722 static int | |
| 2286 | 723 hash_table_rehash_threshold_validate (Lisp_Object UNUSED (keyword), |
| 724 Lisp_Object value, Error_Behavior errb) | |
| 428 | 725 { |
| 726 if (!FLOATP (value)) | |
| 727 { | |
| 563 | 728 maybe_signal_error_1 (Qwrong_type_argument, list2 (Qfloatp, value), |
| 428 | 729 Qhash_table, errb); |
| 730 return 0; | |
| 731 } | |
| 732 | |
| 733 { | |
| 734 double rehash_threshold = XFLOAT_DATA (value); | |
| 735 if (rehash_threshold <= 0.0 || rehash_threshold >= 1.0) | |
| 736 { | |
| 563 | 737 maybe_invalid_argument |
| 428 | 738 ("Hash table rehash threshold must be between 0.0 and 1.0", |
| 739 value, Qhash_table, errb); | |
| 740 return 0; | |
| 741 } | |
| 742 } | |
| 743 | |
| 744 return 1; | |
| 745 } | |
| 746 | |
| 747 static double | |
| 748 decode_hash_table_rehash_threshold (Lisp_Object rehash_threshold) | |
| 749 { | |
| 750 return NILP (rehash_threshold) ? -1.0 : XFLOAT_DATA (rehash_threshold); | |
| 751 } | |
| 752 | |
| 753 static int | |
| 2286 | 754 hash_table_data_validate (Lisp_Object UNUSED (keyword), Lisp_Object value, |
| 755 Error_Behavior errb) | |
| 428 | 756 { |
| 757 int len; | |
| 758 | |
| 759 GET_EXTERNAL_LIST_LENGTH (value, len); | |
| 760 | |
| 761 if (len & 1) | |
| 762 { | |
| 563 | 763 maybe_sferror |
| 428 | 764 ("Hash table data must have alternating key/value pairs", |
| 765 value, Qhash_table, errb); | |
| 766 return 0; | |
| 767 } | |
| 768 return 1; | |
| 769 } | |
| 770 | |
| 771 /* The actual instantiation of a hash table. This does practically no | |
| 772 error checking, because it relies on the fact that the paranoid | |
| 773 functions above have error-checked everything to the last details. | |
| 774 If this assumption is wrong, we will get a crash immediately (with | |
| 775 error-checking compiled in), and we'll know if there is a bug in | |
| 776 the structure mechanism. So there. */ | |
| 777 static Lisp_Object | |
| 778 hash_table_instantiate (Lisp_Object plist) | |
| 779 { | |
| 780 Lisp_Object hash_table; | |
| 781 Lisp_Object test = Qnil; | |
| 782 Lisp_Object size = Qnil; | |
| 783 Lisp_Object rehash_size = Qnil; | |
| 784 Lisp_Object rehash_threshold = Qnil; | |
| 785 Lisp_Object weakness = Qnil; | |
| 786 Lisp_Object data = Qnil; | |
| 787 | |
| 2421 | 788 PROPERTY_LIST_LOOP_3 (key, value, plist) |
| 428 | 789 { |
| 790 if (EQ (key, Qtest)) test = value; | |
| 791 else if (EQ (key, Qsize)) size = value; | |
| 792 else if (EQ (key, Qrehash_size)) rehash_size = value; | |
| 793 else if (EQ (key, Qrehash_threshold)) rehash_threshold = value; | |
| 794 else if (EQ (key, Qweakness)) weakness = value; | |
| 795 else if (EQ (key, Qdata)) data = value; | |
| 796 else if (EQ (key, Qtype))/*obsolete*/ weakness = value; | |
| 797 else | |
| 2500 | 798 ABORT (); |
| 428 | 799 } |
| 800 | |
| 801 /* Create the hash table. */ | |
| 450 | 802 hash_table = make_standard_lisp_hash_table |
| 428 | 803 (decode_hash_table_test (test), |
| 804 decode_hash_table_size (size), | |
| 805 decode_hash_table_rehash_size (rehash_size), | |
| 806 decode_hash_table_rehash_threshold (rehash_threshold), | |
| 807 decode_hash_table_weakness (weakness)); | |
| 808 | |
| 809 /* I'm not sure whether this can GC, but better safe than sorry. */ | |
| 810 { | |
| 811 struct gcpro gcpro1; | |
| 812 GCPRO1 (hash_table); | |
| 813 | |
| 814 /* And fill it with data. */ | |
| 815 while (!NILP (data)) | |
| 816 { | |
| 817 Lisp_Object key, value; | |
| 818 key = XCAR (data); data = XCDR (data); | |
| 819 value = XCAR (data); data = XCDR (data); | |
| 820 Fputhash (key, value, hash_table); | |
| 821 } | |
| 822 UNGCPRO; | |
| 823 } | |
| 824 | |
| 825 return hash_table; | |
| 826 } | |
| 827 | |
| 828 static void | |
| 829 structure_type_create_hash_table_structure_name (Lisp_Object structure_name) | |
| 830 { | |
| 831 struct structure_type *st; | |
| 832 | |
| 833 st = define_structure_type (structure_name, 0, hash_table_instantiate); | |
| 834 define_structure_type_keyword (st, Qtest, hash_table_test_validate); | |
| 835 define_structure_type_keyword (st, Qsize, hash_table_size_validate); | |
| 836 define_structure_type_keyword (st, Qrehash_size, hash_table_rehash_size_validate); | |
| 837 define_structure_type_keyword (st, Qrehash_threshold, hash_table_rehash_threshold_validate); | |
| 838 define_structure_type_keyword (st, Qweakness, hash_table_weakness_validate); | |
| 839 define_structure_type_keyword (st, Qdata, hash_table_data_validate); | |
| 840 | |
| 841 /* obsolete as of 19990901 in xemacs-21.2 */ | |
| 842 define_structure_type_keyword (st, Qtype, hash_table_weakness_validate); | |
| 843 } | |
| 844 | |
| 845 /* Create a built-in Lisp structure type named `hash-table'. | |
| 846 We make #s(hashtable ...) equivalent to #s(hash-table ...), | |
| 847 for backward compatibility. | |
| 848 This is called from emacs.c. */ | |
| 849 void | |
| 850 structure_type_create_hash_table (void) | |
| 851 { | |
| 852 structure_type_create_hash_table_structure_name (Qhash_table); | |
| 853 structure_type_create_hash_table_structure_name (Qhashtable); /* compat */ | |
| 854 } | |
| 855 | |
| 856 | |
| 857 /************************************************************************/ | |
| 858 /* Definition of Lisp-visible methods */ | |
| 859 /************************************************************************/ | |
| 860 | |
| 861 DEFUN ("hash-table-p", Fhash_table_p, 1, 1, 0, /* | |
| 862 Return t if OBJECT is a hash table, else nil. | |
| 863 */ | |
| 864 (object)) | |
| 865 { | |
| 866 return HASH_TABLEP (object) ? Qt : Qnil; | |
| 867 } | |
| 868 | |
| 869 DEFUN ("make-hash-table", Fmake_hash_table, 0, MANY, 0, /* | |
| 870 Return a new empty hash table object. | |
| 871 Use Common Lisp style keywords to specify hash table properties. | |
| 872 (make-hash-table &key test size rehash-size rehash-threshold weakness) | |
| 873 | |
| 874 Keyword :test can be `eq', `eql' (default) or `equal'. | |
| 875 Comparison between keys is done using this function. | |
| 876 If speed is important, consider using `eq'. | |
| 877 When storing strings in the hash table, you will likely need to use `equal'. | |
| 878 | |
| 879 Keyword :size specifies the number of keys likely to be inserted. | |
| 880 This number of entries can be inserted without enlarging the hash table. | |
| 881 | |
| 882 Keyword :rehash-size must be a float greater than 1.0, and specifies | |
| 883 the factor by which to increase the size of the hash table when enlarging. | |
| 884 | |
| 885 Keyword :rehash-threshold must be a float between 0.0 and 1.0, | |
| 886 and specifies the load factor of the hash table which triggers enlarging. | |
| 887 | |
| 442 | 888 Non-standard keyword :weakness can be `nil' (default), `t', `key-and-value', |
| 889 `key', `value' or `key-or-value'. `t' is an alias for `key-and-value'. | |
| 428 | 890 |
| 442 | 891 A key-and-value-weak hash table, also known as a fully-weak or simply |
| 892 as a weak hash table, is one whose pointers do not count as GC | |
| 893 referents: for any key-value pair in the hash table, if the only | |
| 894 remaining pointer to either the key or the value is in a weak hash | |
| 895 table, then the pair will be removed from the hash table, and the key | |
| 896 and value collected. A non-weak hash table (or any other pointer) | |
| 897 would prevent the object from being collected. | |
| 428 | 898 |
| 899 A key-weak hash table is similar to a fully-weak hash table except that | |
| 900 a key-value pair will be removed only if the key remains unmarked | |
| 901 outside of weak hash tables. The pair will remain in the hash table if | |
| 902 the key is pointed to by something other than a weak hash table, even | |
| 903 if the value is not. | |
| 904 | |
| 905 A value-weak hash table is similar to a fully-weak hash table except | |
| 906 that a key-value pair will be removed only if the value remains | |
| 907 unmarked outside of weak hash tables. The pair will remain in the | |
| 908 hash table if the value is pointed to by something other than a weak | |
| 909 hash table, even if the key is not. | |
| 442 | 910 |
| 911 A key-or-value-weak hash table is similar to a fully-weak hash table except | |
| 912 that a key-value pair will be removed only if the value and the key remain | |
| 913 unmarked outside of weak hash tables. The pair will remain in the | |
| 914 hash table if the value or key are pointed to by something other than a weak | |
| 915 hash table, even if the other is not. | |
| 428 | 916 */ |
| 917 (int nargs, Lisp_Object *args)) | |
| 918 { | |
| 919 int i = 0; | |
| 920 Lisp_Object test = Qnil; | |
| 921 Lisp_Object size = Qnil; | |
| 922 Lisp_Object rehash_size = Qnil; | |
| 923 Lisp_Object rehash_threshold = Qnil; | |
| 924 Lisp_Object weakness = Qnil; | |
| 925 | |
| 926 while (i + 1 < nargs) | |
| 927 { | |
| 928 Lisp_Object keyword = args[i++]; | |
| 929 Lisp_Object value = args[i++]; | |
| 930 | |
| 931 if (EQ (keyword, Q_test)) test = value; | |
| 932 else if (EQ (keyword, Q_size)) size = value; | |
| 933 else if (EQ (keyword, Q_rehash_size)) rehash_size = value; | |
| 934 else if (EQ (keyword, Q_rehash_threshold)) rehash_threshold = value; | |
| 935 else if (EQ (keyword, Q_weakness)) weakness = value; | |
| 936 else if (EQ (keyword, Q_type))/*obsolete*/ weakness = value; | |
| 563 | 937 else invalid_constant ("Invalid hash table property keyword", keyword); |
| 428 | 938 } |
| 939 | |
| 940 if (i < nargs) | |
| 563 | 941 sferror ("Hash table property requires a value", args[i]); |
| 428 | 942 |
| 943 #define VALIDATE_VAR(var) \ | |
| 944 if (!NILP (var)) hash_table_##var##_validate (Q##var, var, ERROR_ME); | |
| 945 | |
| 946 VALIDATE_VAR (test); | |
| 947 VALIDATE_VAR (size); | |
| 948 VALIDATE_VAR (rehash_size); | |
| 949 VALIDATE_VAR (rehash_threshold); | |
| 950 VALIDATE_VAR (weakness); | |
| 951 | |
| 450 | 952 return make_standard_lisp_hash_table |
| 428 | 953 (decode_hash_table_test (test), |
| 954 decode_hash_table_size (size), | |
| 955 decode_hash_table_rehash_size (rehash_size), | |
| 956 decode_hash_table_rehash_threshold (rehash_threshold), | |
| 957 decode_hash_table_weakness (weakness)); | |
| 958 } | |
| 959 | |
| 960 DEFUN ("copy-hash-table", Fcopy_hash_table, 1, 1, 0, /* | |
| 961 Return a new hash table containing the same keys and values as HASH-TABLE. | |
| 962 The keys and values will not themselves be copied. | |
| 963 */ | |
| 964 (hash_table)) | |
| 965 { | |
| 442 | 966 const Lisp_Hash_Table *ht_old = xhash_table (hash_table); |
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967 Lisp_Object obj = ALLOC_LISP_OBJECT (hash_table); |
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968 Lisp_Hash_Table *ht = XHASH_TABLE (obj); |
| 3017 | 969 COPY_LCRECORD (ht, ht_old); |
| 428 | 970 |
| 1204 | 971 ht->hentries = xnew_array (htentry, ht_old->size + 1); |
| 972 memcpy (ht->hentries, ht_old->hentries, (ht_old->size + 1) * sizeof (htentry)); | |
| 428 | 973 |
| 974 if (! EQ (ht->next_weak, Qunbound)) | |
| 975 { | |
| 976 ht->next_weak = Vall_weak_hash_tables; | |
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977 Vall_weak_hash_tables = obj; |
| 428 | 978 } |
| 979 | |
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980 return obj; |
| 428 | 981 } |
| 982 | |
| 983 static void | |
| 665 | 984 resize_hash_table (Lisp_Hash_Table *ht, Elemcount new_size) |
| 428 | 985 { |
| 1204 | 986 htentry *old_entries, *new_entries, *sentinel, *e; |
| 665 | 987 Elemcount old_size; |
| 428 | 988 |
| 989 old_size = ht->size; | |
| 990 ht->size = new_size; | |
| 991 | |
| 992 old_entries = ht->hentries; | |
| 993 | |
| 1204 | 994 ht->hentries = xnew_array_and_zero (htentry, new_size + 1); |
| 428 | 995 new_entries = ht->hentries; |
| 996 | |
| 997 compute_hash_table_derived_values (ht); | |
| 998 | |
| 440 | 999 for (e = old_entries, sentinel = e + old_size; e < sentinel; e++) |
| 1204 | 1000 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 1001 { |
| 1204 | 1002 htentry *probe = new_entries + HASHCODE (e->key, ht); |
| 428 | 1003 LINEAR_PROBING_LOOP (probe, new_entries, new_size) |
| 1004 ; | |
| 1005 *probe = *e; | |
| 1006 } | |
| 1007 | |
| 489 | 1008 free_hentries (old_entries, old_size); |
| 428 | 1009 } |
| 1010 | |
| 440 | 1011 /* After a hash table has been saved to disk and later restored by the |
| 1012 portable dumper, it contains the same objects, but their addresses | |
| 665 | 1013 and thus their HASHCODEs have changed. */ |
| 428 | 1014 void |
| 440 | 1015 pdump_reorganize_hash_table (Lisp_Object hash_table) |
| 428 | 1016 { |
| 442 | 1017 const Lisp_Hash_Table *ht = xhash_table (hash_table); |
| 1204 | 1018 htentry *new_entries = xnew_array_and_zero (htentry, ht->size + 1); |
| 1019 htentry *e, *sentinel; | |
| 440 | 1020 |
| 1021 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++) | |
| 1204 | 1022 if (!HTENTRY_CLEAR_P (e)) |
| 440 | 1023 { |
| 1204 | 1024 htentry *probe = new_entries + HASHCODE (e->key, ht); |
| 440 | 1025 LINEAR_PROBING_LOOP (probe, new_entries, ht->size) |
| 1026 ; | |
| 1027 *probe = *e; | |
| 1028 } | |
| 1029 | |
| 1204 | 1030 memcpy (ht->hentries, new_entries, ht->size * sizeof (htentry)); |
| 440 | 1031 |
| 1726 | 1032 xfree (new_entries, htentry *); |
| 428 | 1033 } |
| 1034 | |
| 1035 static void | |
| 1036 enlarge_hash_table (Lisp_Hash_Table *ht) | |
| 1037 { | |
| 665 | 1038 Elemcount new_size = |
| 1039 hash_table_size ((Elemcount) ((double) ht->size * ht->rehash_size)); | |
| 428 | 1040 resize_hash_table (ht, new_size); |
| 1041 } | |
| 1042 | |
| 1204 | 1043 static htentry * |
| 1044 find_htentry (Lisp_Object key, const Lisp_Hash_Table *ht) | |
| 428 | 1045 { |
| 1046 hash_table_test_function_t test_function = ht->test_function; | |
| 1204 | 1047 htentry *entries = ht->hentries; |
| 1048 htentry *probe = entries + HASHCODE (key, ht); | |
| 428 | 1049 |
| 1050 LINEAR_PROBING_LOOP (probe, entries, ht->size) | |
| 1051 if (KEYS_EQUAL_P (probe->key, key, test_function)) | |
| 1052 break; | |
| 1053 | |
| 1054 return probe; | |
| 1055 } | |
| 1056 | |
| 2421 | 1057 /* A version of Fputhash() that increments the value by the specified |
| 1058 amount and dispenses will all error checks. Assumes that tables does | |
| 1059 comparison using EQ. Used by the profiling routines to avoid | |
| 1060 overhead -- profiling overhead was being recorded at up to 15% of the | |
| 1061 total time. */ | |
| 1062 | |
| 1063 void | |
| 1064 inchash_eq (Lisp_Object key, Lisp_Object table, EMACS_INT offset) | |
| 1065 { | |
| 1066 Lisp_Hash_Table *ht = XHASH_TABLE (table); | |
| 1067 htentry *entries = ht->hentries; | |
| 1068 htentry *probe = entries + HASHCODE (key, ht); | |
| 1069 | |
| 1070 LINEAR_PROBING_LOOP (probe, entries, ht->size) | |
| 1071 if (EQ (probe->key, key)) | |
| 1072 break; | |
| 1073 | |
| 1074 if (!HTENTRY_CLEAR_P (probe)) | |
| 1075 probe->value = make_int (XINT (probe->value) + offset); | |
| 1076 else | |
| 1077 { | |
| 1078 probe->key = key; | |
| 1079 probe->value = make_int (offset); | |
| 1080 | |
| 1081 if (++ht->count >= ht->rehash_count) | |
| 1082 enlarge_hash_table (ht); | |
| 1083 } | |
| 1084 } | |
| 1085 | |
| 428 | 1086 DEFUN ("gethash", Fgethash, 2, 3, 0, /* |
| 1087 Find hash value for KEY in HASH-TABLE. | |
| 1088 If there is no corresponding value, return DEFAULT (which defaults to nil). | |
| 1089 */ | |
| 1090 (key, hash_table, default_)) | |
| 1091 { | |
| 442 | 1092 const Lisp_Hash_Table *ht = xhash_table (hash_table); |
| 1204 | 1093 htentry *e = find_htentry (key, ht); |
| 428 | 1094 |
| 1204 | 1095 return HTENTRY_CLEAR_P (e) ? default_ : e->value; |
| 428 | 1096 } |
| 1097 | |
| 1098 DEFUN ("puthash", Fputhash, 3, 3, 0, /* | |
| 1099 Hash KEY to VALUE in HASH-TABLE. | |
| 1100 */ | |
| 1101 (key, value, hash_table)) | |
| 1102 { | |
| 1103 Lisp_Hash_Table *ht = xhash_table (hash_table); | |
| 1204 | 1104 htentry *e = find_htentry (key, ht); |
| 428 | 1105 |
| 1204 | 1106 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 1107 return e->value = value; |
| 1108 | |
| 1109 e->key = key; | |
| 1110 e->value = value; | |
| 1111 | |
| 1112 if (++ht->count >= ht->rehash_count) | |
| 1113 enlarge_hash_table (ht); | |
| 1114 | |
| 1115 return value; | |
| 1116 } | |
| 1117 | |
| 1204 | 1118 /* Remove htentry pointed at by PROBE. |
| 428 | 1119 Subsequent entries are removed and reinserted. |
| 1120 We don't use tombstones - too wasteful. */ | |
| 1121 static void | |
| 1204 | 1122 remhash_1 (Lisp_Hash_Table *ht, htentry *entries, htentry *probe) |
| 428 | 1123 { |
| 665 | 1124 Elemcount size = ht->size; |
| 1204 | 1125 CLEAR_HTENTRY (probe); |
| 428 | 1126 probe++; |
| 1127 ht->count--; | |
| 1128 | |
| 1129 LINEAR_PROBING_LOOP (probe, entries, size) | |
| 1130 { | |
| 1131 Lisp_Object key = probe->key; | |
| 1204 | 1132 htentry *probe2 = entries + HASHCODE (key, ht); |
| 428 | 1133 LINEAR_PROBING_LOOP (probe2, entries, size) |
| 1134 if (EQ (probe2->key, key)) | |
| 1204 | 1135 /* htentry at probe doesn't need to move. */ |
| 428 | 1136 goto continue_outer_loop; |
| 1204 | 1137 /* Move htentry from probe to new home at probe2. */ |
| 428 | 1138 *probe2 = *probe; |
| 1204 | 1139 CLEAR_HTENTRY (probe); |
| 428 | 1140 continue_outer_loop: continue; |
| 1141 } | |
| 1142 } | |
| 1143 | |
| 1144 DEFUN ("remhash", Fremhash, 2, 2, 0, /* | |
| 1145 Remove the entry for KEY from HASH-TABLE. | |
| 1146 Do nothing if there is no entry for KEY in HASH-TABLE. | |
| 617 | 1147 Return non-nil if an entry was removed. |
| 428 | 1148 */ |
| 1149 (key, hash_table)) | |
| 1150 { | |
| 1151 Lisp_Hash_Table *ht = xhash_table (hash_table); | |
| 1204 | 1152 htentry *e = find_htentry (key, ht); |
| 428 | 1153 |
| 1204 | 1154 if (HTENTRY_CLEAR_P (e)) |
| 428 | 1155 return Qnil; |
| 1156 | |
| 1157 remhash_1 (ht, ht->hentries, e); | |
| 1158 return Qt; | |
| 1159 } | |
| 1160 | |
| 1161 DEFUN ("clrhash", Fclrhash, 1, 1, 0, /* | |
| 1162 Remove all entries from HASH-TABLE, leaving it empty. | |
| 1163 */ | |
| 1164 (hash_table)) | |
| 1165 { | |
| 1166 Lisp_Hash_Table *ht = xhash_table (hash_table); | |
| 1204 | 1167 htentry *e, *sentinel; |
| 428 | 1168 |
| 1169 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++) | |
| 1204 | 1170 CLEAR_HTENTRY (e); |
| 428 | 1171 ht->count = 0; |
| 1172 | |
| 1173 return hash_table; | |
| 1174 } | |
| 1175 | |
| 1176 /************************************************************************/ | |
| 1177 /* Accessor Functions */ | |
| 1178 /************************************************************************/ | |
| 1179 | |
| 1180 DEFUN ("hash-table-count", Fhash_table_count, 1, 1, 0, /* | |
| 1181 Return the number of entries in HASH-TABLE. | |
| 1182 */ | |
| 1183 (hash_table)) | |
| 1184 { | |
| 1185 return make_int (xhash_table (hash_table)->count); | |
| 1186 } | |
| 1187 | |
| 1188 DEFUN ("hash-table-test", Fhash_table_test, 1, 1, 0, /* | |
| 1189 Return the test function of HASH-TABLE. | |
| 1190 This can be one of `eq', `eql' or `equal'. | |
| 1191 */ | |
| 1192 (hash_table)) | |
| 1193 { | |
| 1194 hash_table_test_function_t fun = xhash_table (hash_table)->test_function; | |
| 1195 | |
| 1196 return (fun == lisp_object_eql_equal ? Qeql : | |
| 1197 fun == lisp_object_equal_equal ? Qequal : | |
| 1198 Qeq); | |
| 1199 } | |
| 1200 | |
| 1201 DEFUN ("hash-table-size", Fhash_table_size, 1, 1, 0, /* | |
| 1202 Return the size of HASH-TABLE. | |
| 1203 This is the current number of slots in HASH-TABLE, whether occupied or not. | |
| 1204 */ | |
| 1205 (hash_table)) | |
| 1206 { | |
| 1207 return make_int (xhash_table (hash_table)->size); | |
| 1208 } | |
| 1209 | |
| 1210 DEFUN ("hash-table-rehash-size", Fhash_table_rehash_size, 1, 1, 0, /* | |
| 1211 Return the current rehash size of HASH-TABLE. | |
| 1212 This is a float greater than 1.0; the factor by which HASH-TABLE | |
| 1213 is enlarged when the rehash threshold is exceeded. | |
| 1214 */ | |
| 1215 (hash_table)) | |
| 1216 { | |
| 1217 return make_float (xhash_table (hash_table)->rehash_size); | |
| 1218 } | |
| 1219 | |
| 1220 DEFUN ("hash-table-rehash-threshold", Fhash_table_rehash_threshold, 1, 1, 0, /* | |
| 1221 Return the current rehash threshold of HASH-TABLE. | |
| 1222 This is a float between 0.0 and 1.0; the maximum `load factor' of HASH-TABLE, | |
| 1223 beyond which the HASH-TABLE is enlarged by rehashing. | |
| 1224 */ | |
| 1225 (hash_table)) | |
| 1226 { | |
| 438 | 1227 return make_float (xhash_table (hash_table)->rehash_threshold); |
| 428 | 1228 } |
| 1229 | |
| 1230 DEFUN ("hash-table-weakness", Fhash_table_weakness, 1, 1, 0, /* | |
| 1231 Return the weakness of HASH-TABLE. | |
| 442 | 1232 This can be one of `nil', `key-and-value', `key-or-value', `key' or `value'. |
| 428 | 1233 */ |
| 1234 (hash_table)) | |
| 1235 { | |
| 1236 switch (xhash_table (hash_table)->weakness) | |
| 1237 { | |
| 442 | 1238 case HASH_TABLE_WEAK: return Qkey_and_value; |
| 1239 case HASH_TABLE_KEY_WEAK: return Qkey; | |
| 1240 case HASH_TABLE_KEY_VALUE_WEAK: return Qkey_or_value; | |
| 1241 case HASH_TABLE_VALUE_WEAK: return Qvalue; | |
| 1242 default: return Qnil; | |
| 428 | 1243 } |
| 1244 } | |
| 1245 | |
| 1246 /* obsolete as of 19990901 in xemacs-21.2 */ | |
| 1247 DEFUN ("hash-table-type", Fhash_table_type, 1, 1, 0, /* | |
| 1248 Return the type of HASH-TABLE. | |
| 1249 This can be one of `non-weak', `weak', `key-weak' or `value-weak'. | |
| 1250 */ | |
| 1251 (hash_table)) | |
| 1252 { | |
| 1253 switch (xhash_table (hash_table)->weakness) | |
| 1254 { | |
| 442 | 1255 case HASH_TABLE_WEAK: return Qweak; |
| 1256 case HASH_TABLE_KEY_WEAK: return Qkey_weak; | |
| 1257 case HASH_TABLE_KEY_VALUE_WEAK: return Qkey_or_value_weak; | |
| 1258 case HASH_TABLE_VALUE_WEAK: return Qvalue_weak; | |
| 1259 default: return Qnon_weak; | |
| 428 | 1260 } |
| 1261 } | |
| 1262 | |
| 1263 /************************************************************************/ | |
| 1264 /* Mapping Functions */ | |
| 1265 /************************************************************************/ | |
| 489 | 1266 |
| 1267 /* We need to be careful when mapping over hash tables because the | |
| 1268 hash table might be modified during the mapping operation: | |
| 1269 - by the mapping function | |
| 1270 - by gc (if the hash table is weak) | |
| 1271 | |
| 1272 So we make a copy of the hentries at the beginning of the mapping | |
| 497 | 1273 operation, and iterate over the copy. Naturally, this is |
| 1274 expensive, but not as expensive as you might think, because no | |
| 1275 actual memory has to be collected by our notoriously inefficient | |
| 1276 GC; we use an unwind-protect instead to free the memory directly. | |
| 1277 | |
| 1278 We could avoid the copying by having the hash table modifiers | |
| 1279 puthash and remhash check for currently active mapping functions. | |
| 1280 Disadvantages: it's hard to get right, and IMO hash mapping | |
| 1281 functions are basically rare, and no extra space in the hash table | |
| 1282 object and no extra cpu in puthash or remhash should be wasted to | |
| 1283 make maphash 3% faster. From a design point of view, the basic | |
| 1284 functions gethash, puthash and remhash should be implementable | |
| 1285 without having to think about maphash. | |
| 1286 | |
| 1287 Note: We don't (yet) have Common Lisp's with-hash-table-iterator. | |
| 1288 If you implement this naively, you cannot have more than one | |
| 1289 concurrently active iterator over the same hash table. The `each' | |
| 1290 function in perl has this limitation. | |
| 1291 | |
| 1292 Note: We GCPRO memory on the heap, not on the stack. There is no | |
| 1293 obvious reason why this is bad, but as of this writing this is the | |
| 1294 only known occurrence of this technique in the code. | |
| 504 | 1295 |
| 1296 -- Martin | |
| 1297 */ | |
| 1298 | |
| 1299 /* Ben disagrees with the "copying hentries" design, and says: | |
| 1300 | |
| 1301 Another solution is the same as I've already proposed -- when | |
| 1302 mapping, mark the table as "change-unsafe", and in this case, use a | |
| 1303 secondary table to maintain changes. this could be basically a | |
| 1304 standard hash table, but with entries only for added or deleted | |
| 1305 entries in the primary table, and a marker like Qunbound to | |
| 1306 indicate a deleted entry. puthash, gethash and remhash need a | |
| 1307 single extra check for this secondary table -- totally | |
| 1308 insignificant speedwise. if you really cared about making | |
| 1309 recursive maphashes completely correct, you'd have to do a bit of | |
| 1310 extra work here -- when maphashing, if the secondary table exists, | |
| 1311 make a copy of it, and use the copy in conjunction with the primary | |
| 1312 table when mapping. the advantages of this are | |
| 1313 | |
| 1314 [a] easy to demonstrate correct, even with weak hashtables. | |
| 1315 | |
| 1316 [b] no extra overhead in the general maphash case -- only when you | |
| 1317 modify the table while maphashing, and even then the overhead is | |
| 1318 very small. | |
| 497 | 1319 */ |
| 1320 | |
| 489 | 1321 static Lisp_Object |
| 1322 maphash_unwind (Lisp_Object unwind_obj) | |
| 1323 { | |
| 1324 void *ptr = (void *) get_opaque_ptr (unwind_obj); | |
| 1726 | 1325 xfree (ptr, void *); |
| 489 | 1326 free_opaque_ptr (unwind_obj); |
| 1327 return Qnil; | |
| 1328 } | |
| 1329 | |
| 1330 /* Return a malloced array of alternating key/value pairs from HT. */ | |
| 1331 static Lisp_Object * | |
| 1332 copy_compress_hentries (const Lisp_Hash_Table *ht) | |
| 1333 { | |
| 1334 Lisp_Object * const objs = | |
| 1335 /* If the hash table is empty, ht->count could be 0. */ | |
| 1336 xnew_array (Lisp_Object, 2 * (ht->count > 0 ? ht->count : 1)); | |
| 1204 | 1337 const htentry *e, *sentinel; |
| 489 | 1338 Lisp_Object *pobj; |
| 1339 | |
| 1340 for (e = ht->hentries, sentinel = e + ht->size, pobj = objs; e < sentinel; e++) | |
| 1204 | 1341 if (!HTENTRY_CLEAR_P (e)) |
| 489 | 1342 { |
| 1343 *(pobj++) = e->key; | |
| 1344 *(pobj++) = e->value; | |
| 1345 } | |
| 1346 | |
| 1347 type_checking_assert (pobj == objs + 2 * ht->count); | |
| 1348 | |
| 1349 return objs; | |
| 1350 } | |
| 1351 | |
| 428 | 1352 DEFUN ("maphash", Fmaphash, 2, 2, 0, /* |
| 1353 Map FUNCTION over entries in HASH-TABLE, calling it with two args, | |
| 1354 each key and value in HASH-TABLE. | |
| 1355 | |
| 489 | 1356 FUNCTION must not modify HASH-TABLE, with the one exception that FUNCTION |
| 428 | 1357 may remhash or puthash the entry currently being processed by FUNCTION. |
| 1358 */ | |
| 1359 (function, hash_table)) | |
| 1360 { | |
| 489 | 1361 const Lisp_Hash_Table * const ht = xhash_table (hash_table); |
| 1362 Lisp_Object * const objs = copy_compress_hentries (ht); | |
| 1363 Lisp_Object args[3]; | |
| 1364 const Lisp_Object *pobj, *end; | |
| 1365 int speccount = specpdl_depth (); | |
| 1366 struct gcpro gcpro1; | |
| 1367 | |
| 1368 record_unwind_protect (maphash_unwind, make_opaque_ptr ((void *)objs)); | |
| 1369 GCPRO1 (objs[0]); | |
| 1370 gcpro1.nvars = 2 * ht->count; | |
| 428 | 1371 |
| 489 | 1372 args[0] = function; |
| 1373 | |
| 1374 for (pobj = objs, end = pobj + 2 * ht->count; pobj < end; pobj += 2) | |
| 1375 { | |
| 1376 args[1] = pobj[0]; | |
| 1377 args[2] = pobj[1]; | |
| 1378 Ffuncall (countof (args), args); | |
| 1379 } | |
| 1380 | |
| 771 | 1381 unbind_to (speccount); |
| 489 | 1382 UNGCPRO; |
| 428 | 1383 |
| 1384 return Qnil; | |
| 1385 } | |
| 1386 | |
| 489 | 1387 /* Map *C* function FUNCTION over the elements of a non-weak lisp hash table. |
| 1388 FUNCTION must not modify HASH-TABLE, with the one exception that FUNCTION | |
| 1389 may puthash the entry currently being processed by FUNCTION. | |
| 1390 Mapping terminates if FUNCTION returns something other than 0. */ | |
| 428 | 1391 void |
| 489 | 1392 elisp_maphash_unsafe (maphash_function_t function, |
| 428 | 1393 Lisp_Object hash_table, void *extra_arg) |
| 1394 { | |
| 442 | 1395 const Lisp_Hash_Table *ht = XHASH_TABLE (hash_table); |
| 1204 | 1396 const htentry *e, *sentinel; |
| 428 | 1397 |
| 1398 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++) | |
| 1204 | 1399 if (!HTENTRY_CLEAR_P (e)) |
| 489 | 1400 if (function (e->key, e->value, extra_arg)) |
| 1401 return; | |
| 428 | 1402 } |
| 1403 | |
| 489 | 1404 /* Map *C* function FUNCTION over the elements of a lisp hash table. |
| 1405 It is safe for FUNCTION to modify HASH-TABLE. | |
| 1406 Mapping terminates if FUNCTION returns something other than 0. */ | |
| 1407 void | |
| 1408 elisp_maphash (maphash_function_t function, | |
| 1409 Lisp_Object hash_table, void *extra_arg) | |
| 1410 { | |
| 1411 const Lisp_Hash_Table * const ht = xhash_table (hash_table); | |
| 1412 Lisp_Object * const objs = copy_compress_hentries (ht); | |
| 1413 const Lisp_Object *pobj, *end; | |
| 1414 int speccount = specpdl_depth (); | |
| 1415 struct gcpro gcpro1; | |
| 1416 | |
| 1417 record_unwind_protect (maphash_unwind, make_opaque_ptr ((void *)objs)); | |
| 1418 GCPRO1 (objs[0]); | |
| 1419 gcpro1.nvars = 2 * ht->count; | |
| 1420 | |
| 1421 for (pobj = objs, end = pobj + 2 * ht->count; pobj < end; pobj += 2) | |
| 1422 if (function (pobj[0], pobj[1], extra_arg)) | |
| 1423 break; | |
| 1424 | |
| 771 | 1425 unbind_to (speccount); |
| 489 | 1426 UNGCPRO; |
| 1427 } | |
| 1428 | |
| 1429 /* Remove all elements of a lisp hash table satisfying *C* predicate PREDICATE. | |
| 1430 PREDICATE must not modify HASH-TABLE. */ | |
| 428 | 1431 void |
| 1432 elisp_map_remhash (maphash_function_t predicate, | |
| 1433 Lisp_Object hash_table, void *extra_arg) | |
| 1434 { | |
| 489 | 1435 const Lisp_Hash_Table * const ht = xhash_table (hash_table); |
| 1436 Lisp_Object * const objs = copy_compress_hentries (ht); | |
| 1437 const Lisp_Object *pobj, *end; | |
| 1438 int speccount = specpdl_depth (); | |
| 1439 struct gcpro gcpro1; | |
| 428 | 1440 |
| 489 | 1441 record_unwind_protect (maphash_unwind, make_opaque_ptr ((void *)objs)); |
| 1442 GCPRO1 (objs[0]); | |
| 1443 gcpro1.nvars = 2 * ht->count; | |
| 1444 | |
| 1445 for (pobj = objs, end = pobj + 2 * ht->count; pobj < end; pobj += 2) | |
| 1446 if (predicate (pobj[0], pobj[1], extra_arg)) | |
| 1447 Fremhash (pobj[0], hash_table); | |
| 1448 | |
| 771 | 1449 unbind_to (speccount); |
| 489 | 1450 UNGCPRO; |
| 428 | 1451 } |
| 1452 | |
| 1453 | |
| 1454 /************************************************************************/ | |
| 1455 /* garbage collecting weak hash tables */ | |
| 1456 /************************************************************************/ | |
| 1598 | 1457 #ifdef USE_KKCC |
| 2645 | 1458 #define MARK_OBJ(obj) do { \ |
| 1459 Lisp_Object mo_obj = (obj); \ | |
| 1460 if (!marked_p (mo_obj)) \ | |
| 1461 { \ | |
| 1462 kkcc_gc_stack_push_lisp_object (mo_obj, 0, -1); \ | |
| 1463 did_mark = 1; \ | |
| 1464 } \ | |
| 1598 | 1465 } while (0) |
| 1466 | |
| 1467 #else /* NO USE_KKCC */ | |
| 1468 | |
| 442 | 1469 #define MARK_OBJ(obj) do { \ |
| 1470 Lisp_Object mo_obj = (obj); \ | |
| 1471 if (!marked_p (mo_obj)) \ | |
| 1472 { \ | |
| 1473 mark_object (mo_obj); \ | |
| 1474 did_mark = 1; \ | |
| 1475 } \ | |
| 1476 } while (0) | |
| 1598 | 1477 #endif /*NO USE_KKCC */ |
| 442 | 1478 |
| 428 | 1479 |
| 1480 /* Complete the marking for semi-weak hash tables. */ | |
| 1481 int | |
| 1482 finish_marking_weak_hash_tables (void) | |
| 1483 { | |
| 1484 Lisp_Object hash_table; | |
| 1485 int did_mark = 0; | |
| 1486 | |
| 1487 for (hash_table = Vall_weak_hash_tables; | |
| 1488 !NILP (hash_table); | |
| 1489 hash_table = XHASH_TABLE (hash_table)->next_weak) | |
| 1490 { | |
| 442 | 1491 const Lisp_Hash_Table *ht = XHASH_TABLE (hash_table); |
| 1204 | 1492 const htentry *e = ht->hentries; |
| 1493 const htentry *sentinel = e + ht->size; | |
| 428 | 1494 |
| 1495 if (! marked_p (hash_table)) | |
| 1496 /* The hash table is probably garbage. Ignore it. */ | |
| 1497 continue; | |
| 1498 | |
| 1499 /* Now, scan over all the pairs. For all pairs that are | |
| 1500 half-marked, we may need to mark the other half if we're | |
| 1501 keeping this pair. */ | |
| 1502 switch (ht->weakness) | |
| 1503 { | |
| 1504 case HASH_TABLE_KEY_WEAK: | |
| 1505 for (; e < sentinel; e++) | |
| 1204 | 1506 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 1507 if (marked_p (e->key)) |
| 1508 MARK_OBJ (e->value); | |
| 1509 break; | |
| 1510 | |
| 1511 case HASH_TABLE_VALUE_WEAK: | |
| 1512 for (; e < sentinel; e++) | |
| 1204 | 1513 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 1514 if (marked_p (e->value)) |
| 1515 MARK_OBJ (e->key); | |
| 1516 break; | |
| 1517 | |
| 442 | 1518 case HASH_TABLE_KEY_VALUE_WEAK: |
| 1519 for (; e < sentinel; e++) | |
| 1204 | 1520 if (!HTENTRY_CLEAR_P (e)) |
| 442 | 1521 { |
| 1522 if (marked_p (e->value)) | |
| 1523 MARK_OBJ (e->key); | |
| 1524 else if (marked_p (e->key)) | |
| 1525 MARK_OBJ (e->value); | |
| 1526 } | |
| 1527 break; | |
| 1528 | |
| 428 | 1529 case HASH_TABLE_KEY_CAR_WEAK: |
| 1530 for (; e < sentinel; e++) | |
| 1204 | 1531 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 1532 if (!CONSP (e->key) || marked_p (XCAR (e->key))) |
| 1533 { | |
| 1534 MARK_OBJ (e->key); | |
| 1535 MARK_OBJ (e->value); | |
| 1536 } | |
| 1537 break; | |
| 1538 | |
| 450 | 1539 /* We seem to be sprouting new weakness types at an alarming |
| 1540 rate. At least this is not externally visible - and in | |
| 1541 fact all of these KEY_CAR_* types are only used by the | |
| 1542 glyph code. */ | |
| 1543 case HASH_TABLE_KEY_CAR_VALUE_WEAK: | |
| 1544 for (; e < sentinel; e++) | |
| 1204 | 1545 if (!HTENTRY_CLEAR_P (e)) |
| 450 | 1546 { |
| 1547 if (!CONSP (e->key) || marked_p (XCAR (e->key))) | |
| 1548 { | |
| 1549 MARK_OBJ (e->key); | |
| 1550 MARK_OBJ (e->value); | |
| 1551 } | |
| 1552 else if (marked_p (e->value)) | |
| 1553 MARK_OBJ (e->key); | |
| 1554 } | |
| 1555 break; | |
| 1556 | |
| 428 | 1557 case HASH_TABLE_VALUE_CAR_WEAK: |
| 1558 for (; e < sentinel; e++) | |
| 1204 | 1559 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 1560 if (!CONSP (e->value) || marked_p (XCAR (e->value))) |
| 1561 { | |
| 1562 MARK_OBJ (e->key); | |
| 1563 MARK_OBJ (e->value); | |
| 1564 } | |
| 1565 break; | |
| 1566 | |
| 1567 default: | |
| 1568 break; | |
| 1569 } | |
| 1570 } | |
| 1571 | |
| 1572 return did_mark; | |
| 1573 } | |
| 1574 | |
| 1575 void | |
| 1576 prune_weak_hash_tables (void) | |
| 1577 { | |
| 1578 Lisp_Object hash_table, prev = Qnil; | |
| 1579 for (hash_table = Vall_weak_hash_tables; | |
| 1580 !NILP (hash_table); | |
| 1581 hash_table = XHASH_TABLE (hash_table)->next_weak) | |
| 1582 { | |
| 1583 if (! marked_p (hash_table)) | |
| 1584 { | |
| 1585 /* This hash table itself is garbage. Remove it from the list. */ | |
| 1586 if (NILP (prev)) | |
| 1587 Vall_weak_hash_tables = XHASH_TABLE (hash_table)->next_weak; | |
| 1588 else | |
| 1589 XHASH_TABLE (prev)->next_weak = XHASH_TABLE (hash_table)->next_weak; | |
| 1590 } | |
| 1591 else | |
| 1592 { | |
| 1593 /* Now, scan over all the pairs. Remove all of the pairs | |
| 1594 in which the key or value, or both, is unmarked | |
| 1595 (depending on the weakness of the hash table). */ | |
| 1596 Lisp_Hash_Table *ht = XHASH_TABLE (hash_table); | |
| 1204 | 1597 htentry *entries = ht->hentries; |
| 1598 htentry *sentinel = entries + ht->size; | |
| 1599 htentry *e; | |
| 428 | 1600 |
| 1601 for (e = entries; e < sentinel; e++) | |
| 1204 | 1602 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 1603 { |
| 1604 again: | |
| 1605 if (!marked_p (e->key) || !marked_p (e->value)) | |
| 1606 { | |
| 1607 remhash_1 (ht, entries, e); | |
| 1204 | 1608 if (!HTENTRY_CLEAR_P (e)) |
| 428 | 1609 goto again; |
| 1610 } | |
| 1611 } | |
| 1612 | |
| 1613 prev = hash_table; | |
| 1614 } | |
| 1615 } | |
| 1616 } | |
| 1617 | |
| 1618 /* Return a hash value for an array of Lisp_Objects of size SIZE. */ | |
| 1619 | |
| 665 | 1620 Hashcode |
| 428 | 1621 internal_array_hash (Lisp_Object *arr, int size, int depth) |
| 1622 { | |
| 1623 int i; | |
| 665 | 1624 Hashcode hash = 0; |
| 442 | 1625 depth++; |
| 428 | 1626 |
| 1627 if (size <= 5) | |
| 1628 { | |
| 1629 for (i = 0; i < size; i++) | |
| 442 | 1630 hash = HASH2 (hash, internal_hash (arr[i], depth)); |
| 428 | 1631 return hash; |
| 1632 } | |
| 1633 | |
| 1634 /* just pick five elements scattered throughout the array. | |
| 1635 A slightly better approach would be to offset by some | |
| 1636 noise factor from the points chosen below. */ | |
| 1637 for (i = 0; i < 5; i++) | |
| 442 | 1638 hash = HASH2 (hash, internal_hash (arr[i*size/5], depth)); |
| 428 | 1639 |
| 1640 return hash; | |
| 1641 } | |
| 1642 | |
| 1643 /* Return a hash value for a Lisp_Object. This is for use when hashing | |
| 1644 objects with the comparison being `equal' (for `eq', you can just | |
| 1645 use the Lisp_Object itself as the hash value). You need to make a | |
| 1646 tradeoff between the speed of the hash function and how good the | |
| 1647 hashing is. In particular, the hash function needs to be FAST, | |
| 1648 so you can't just traipse down the whole tree hashing everything | |
| 1649 together. Most of the time, objects will differ in the first | |
| 1650 few elements you hash. Thus, we only go to a short depth (5) | |
| 1651 and only hash at most 5 elements out of a vector. Theoretically | |
| 1652 we could still take 5^5 time (a big big number) to compute a | |
| 1653 hash, but practically this won't ever happen. */ | |
| 1654 | |
| 665 | 1655 Hashcode |
| 428 | 1656 internal_hash (Lisp_Object obj, int depth) |
| 1657 { | |
| 1658 if (depth > 5) | |
| 1659 return 0; | |
| 1660 if (CONSP (obj)) | |
| 1661 { | |
| 1662 /* no point in worrying about tail recursion, since we're not | |
| 1663 going very deep */ | |
| 1664 return HASH2 (internal_hash (XCAR (obj), depth + 1), | |
| 1665 internal_hash (XCDR (obj), depth + 1)); | |
| 1666 } | |
| 1667 if (STRINGP (obj)) | |
| 1668 { | |
| 1669 return hash_string (XSTRING_DATA (obj), XSTRING_LENGTH (obj)); | |
| 1670 } | |
| 1671 if (LRECORDP (obj)) | |
| 1672 { | |
| 442 | 1673 const struct lrecord_implementation |
| 428 | 1674 *imp = XRECORD_LHEADER_IMPLEMENTATION (obj); |
| 1675 if (imp->hash) | |
| 1676 return imp->hash (obj, depth); | |
| 1677 } | |
| 1678 | |
| 1679 return LISP_HASH (obj); | |
| 1680 } | |
| 1681 | |
| 1682 DEFUN ("sxhash", Fsxhash, 1, 1, 0, /* | |
| 1683 Return a hash value for OBJECT. | |
| 444 | 1684 \(equal obj1 obj2) implies (= (sxhash obj1) (sxhash obj2)). |
| 428 | 1685 */ |
| 1686 (object)) | |
| 1687 { | |
| 1688 return make_int (internal_hash (object, 0)); | |
| 1689 } | |
| 1690 | |
| 1691 #if 0 | |
| 826 | 1692 DEFUN ("internal-hash-value", Finternal_hash_value, 1, 1, 0, /* |
| 428 | 1693 Hash value of OBJECT. For debugging. |
| 1694 The value is returned as (HIGH . LOW). | |
| 1695 */ | |
| 1696 (object)) | |
| 1697 { | |
| 1698 /* This function is pretty 32bit-centric. */ | |
| 665 | 1699 Hashcode hash = internal_hash (object, 0); |
| 428 | 1700 return Fcons (hash >> 16, hash & 0xffff); |
| 1701 } | |
| 1702 #endif | |
| 1703 | |
| 1704 | |
| 1705 /************************************************************************/ | |
| 1706 /* initialization */ | |
| 1707 /************************************************************************/ | |
| 1708 | |
| 1709 void | |
| 1710 syms_of_elhash (void) | |
| 1711 { | |
| 1712 DEFSUBR (Fhash_table_p); | |
| 1713 DEFSUBR (Fmake_hash_table); | |
| 1714 DEFSUBR (Fcopy_hash_table); | |
| 1715 DEFSUBR (Fgethash); | |
| 1716 DEFSUBR (Fremhash); | |
| 1717 DEFSUBR (Fputhash); | |
| 1718 DEFSUBR (Fclrhash); | |
| 1719 DEFSUBR (Fmaphash); | |
| 1720 DEFSUBR (Fhash_table_count); | |
| 1721 DEFSUBR (Fhash_table_test); | |
| 1722 DEFSUBR (Fhash_table_size); | |
| 1723 DEFSUBR (Fhash_table_rehash_size); | |
| 1724 DEFSUBR (Fhash_table_rehash_threshold); | |
| 1725 DEFSUBR (Fhash_table_weakness); | |
| 1726 DEFSUBR (Fhash_table_type); /* obsolete */ | |
| 1727 DEFSUBR (Fsxhash); | |
| 1728 #if 0 | |
| 1729 DEFSUBR (Finternal_hash_value); | |
| 1730 #endif | |
| 1731 | |
| 563 | 1732 DEFSYMBOL_MULTIWORD_PREDICATE (Qhash_tablep); |
| 1733 DEFSYMBOL (Qhash_table); | |
| 1734 DEFSYMBOL (Qhashtable); | |
| 1735 DEFSYMBOL (Qweakness); | |
| 1736 DEFSYMBOL (Qvalue); | |
| 1737 DEFSYMBOL (Qkey_or_value); | |
| 1738 DEFSYMBOL (Qkey_and_value); | |
| 1739 DEFSYMBOL (Qrehash_size); | |
| 1740 DEFSYMBOL (Qrehash_threshold); | |
| 428 | 1741 |
| 563 | 1742 DEFSYMBOL (Qweak); /* obsolete */ |
| 1743 DEFSYMBOL (Qkey_weak); /* obsolete */ | |
| 1744 DEFSYMBOL (Qkey_or_value_weak); /* obsolete */ | |
| 1745 DEFSYMBOL (Qvalue_weak); /* obsolete */ | |
| 1746 DEFSYMBOL (Qnon_weak); /* obsolete */ | |
| 428 | 1747 |
| 563 | 1748 DEFKEYWORD (Q_test); |
| 1749 DEFKEYWORD (Q_size); | |
| 1750 DEFKEYWORD (Q_rehash_size); | |
| 1751 DEFKEYWORD (Q_rehash_threshold); | |
| 1752 DEFKEYWORD (Q_weakness); | |
| 1753 DEFKEYWORD (Q_type); /* obsolete */ | |
| 428 | 1754 } |
| 1755 | |
| 1756 void | |
| 771 | 1757 init_elhash_once_early (void) |
| 428 | 1758 { |
|
5117
3742ea8250b5
Checking in final CVS version of workspace 'ben-lisp-object'
Ben Wing <ben@xemacs.org>
parents:
3017
diff
changeset
|
1759 INIT_LISP_OBJECT (hash_table); |
| 771 | 1760 |
| 428 | 1761 /* This must NOT be staticpro'd */ |
| 1762 Vall_weak_hash_tables = Qnil; | |
| 452 | 1763 dump_add_weak_object_chain (&Vall_weak_hash_tables); |
| 428 | 1764 } |