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428
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1 /* Implementation of the hash table lisp object type.
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2 Copyright (C) 1992, 1993, 1994 Free Software Foundation, Inc.
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3 Copyright (C) 1995, 1996 Ben Wing.
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4 Copyright (C) 1997 Free Software Foundation, Inc.
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5
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6 This file is part of XEmacs.
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7
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8 XEmacs is free software; you can redistribute it and/or modify it
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9 under the terms of the GNU General Public License as published by the
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10 Free Software Foundation; either version 2, or (at your option) any
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11 later version.
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12
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13 XEmacs is distributed in the hope that it will be useful, but WITHOUT
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14 ANY WARRANTY; without even the implied warranty of MERCNTABILITY or
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15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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16 for more details.
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17
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18 You should have received a copy of the GNU General Public License
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19 along with XEmacs; see the file COPYING. If not, write to
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20 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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21 Boston, MA 02111-1307, USA. */
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22
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23 /* Synched up with: Not in FSF. */
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24
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489
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25 /* This file implements the hash table lisp object type.
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26
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504
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27 This implementation was mostly written by Martin Buchholz in 1997.
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28
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29 The Lisp-level API (derived from Common Lisp) is almost completely
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30 compatible with GNU Emacs 21, even though the implementations are
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31 totally independent.
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32
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489
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33 The hash table technique used is "linear probing". Collisions are
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34 resolved by putting the item in the next empty place in the array
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35 following the collision. Finding a hash entry performs a linear
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36 search in the cluster starting at the hash value.
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37
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38 On deletions from the hash table, the entries immediately following
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39 the deleted entry are re-entered in the hash table. We do not have
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40 a special way to mark deleted entries (known as "tombstones").
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41
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42 At the end of the hash entries ("hentries"), we leave room for an
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43 entry that is always empty (the "sentinel").
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44
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45 The traditional literature on hash table implementation
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46 (e.g. Knuth) suggests that too much "primary clustering" occurs
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47 with linear probing. However, this literature was written when
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48 locality of reference was not a factor. The discrepancy between
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49 CPU speeds and memory speeds is increasing, and the speed of access
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50 to memory is highly dependent on memory caches which work best when
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51 there is high locality of data reference. Random access to memory
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52 is up to 20 times as expensive as access to the nearest address
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53 (and getting worse). So linear probing makes sense.
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54
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55 But the representation doesn't actually matter that much with the
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56 current elisp engine. Funcall is sufficiently slow that the choice
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57 of hash table implementation is noise. */
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58
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428
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59 #include <config.h>
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60 #include "lisp.h"
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61 #include "bytecode.h"
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62 #include "elhash.h"
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489
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63 #include "opaque.h"
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428
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64
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65 Lisp_Object Qhash_tablep;
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66 static Lisp_Object Qhashtable, Qhash_table;
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442
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67 static Lisp_Object Qweakness, Qvalue, Qkey_or_value, Qkey_and_value;
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428
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68 static Lisp_Object Vall_weak_hash_tables;
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69 static Lisp_Object Qrehash_size, Qrehash_threshold;
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70 static Lisp_Object Q_size, Q_test, Q_weakness, Q_rehash_size, Q_rehash_threshold;
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71
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72 /* obsolete as of 19990901 in xemacs-21.2 */
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442
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73 static Lisp_Object Qweak, Qkey_weak, Qvalue_weak, Qkey_or_value_weak;
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74 static Lisp_Object Qnon_weak, Q_type;
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428
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75
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76 typedef struct hentry
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77 {
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78 Lisp_Object key;
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79 Lisp_Object value;
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80 } hentry;
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81
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82 struct Lisp_Hash_Table
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83 {
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84 struct lcrecord_header header;
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647
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85 Element_Count size;
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86 Element_Count count;
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87 Element_Count rehash_count;
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428
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88 double rehash_size;
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89 double rehash_threshold;
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647
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90 Element_Count golden_ratio;
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428
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91 hash_table_hash_function_t hash_function;
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92 hash_table_test_function_t test_function;
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93 hentry *hentries;
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94 enum hash_table_weakness weakness;
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95 Lisp_Object next_weak; /* Used to chain together all of the weak
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96 hash tables. Don't mark through this. */
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97 };
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98
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99 #define HENTRY_CLEAR_P(hentry) ((*(EMACS_UINT*)(&((hentry)->key))) == 0)
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100 #define CLEAR_HENTRY(hentry) \
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101 ((*(EMACS_UINT*)(&((hentry)->key))) = 0, \
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102 (*(EMACS_UINT*)(&((hentry)->value))) = 0)
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103
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104 #define HASH_TABLE_DEFAULT_SIZE 16
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105 #define HASH_TABLE_DEFAULT_REHASH_SIZE 1.3
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106 #define HASH_TABLE_MIN_SIZE 10
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107
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434
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108 #define HASH_CODE(key, ht) \
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444
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109 ((((ht)->hash_function ? (ht)->hash_function (key) : LISP_HASH (key)) \
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110 * (ht)->golden_ratio) \
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111 % (ht)->size)
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428
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112
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113 #define KEYS_EQUAL_P(key1, key2, testfun) \
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434
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114 (EQ (key1, key2) || ((testfun) && (testfun) (key1, key2)))
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428
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115
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116 #define LINEAR_PROBING_LOOP(probe, entries, size) \
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117 for (; \
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118 !HENTRY_CLEAR_P (probe) || \
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119 (probe == entries + size ? \
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120 (probe = entries, !HENTRY_CLEAR_P (probe)) : 0); \
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121 probe++)
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122
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123 #ifndef ERROR_CHECK_HASH_TABLE
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124 # ifdef ERROR_CHECK_TYPECHECK
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125 # define ERROR_CHECK_HASH_TABLE 1
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126 # else
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127 # define ERROR_CHECK_HASH_TABLE 0
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128 # endif
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129 #endif
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130
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131 #if ERROR_CHECK_HASH_TABLE
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132 static void
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133 check_hash_table_invariants (Lisp_Hash_Table *ht)
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134 {
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135 assert (ht->count < ht->size);
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136 assert (ht->count <= ht->rehash_count);
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137 assert (ht->rehash_count < ht->size);
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138 assert ((double) ht->count * ht->rehash_threshold - 1 <= (double) ht->rehash_count);
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139 assert (HENTRY_CLEAR_P (ht->hentries + ht->size));
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140 }
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141 #else
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142 #define check_hash_table_invariants(ht)
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143 #endif
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144
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145 /* Return a suitable size for a hash table, with at least SIZE slots. */
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647
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146 static Element_Count
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147 hash_table_size (Element_Count requested_size)
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428
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148 {
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149 /* Return some prime near, but greater than or equal to, SIZE.
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150 Decades from the time of writing, someone will have a system large
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151 enough that the list below will be too short... */
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647
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152 static const Element_Count primes [] =
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428
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153 {
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154 19, 29, 41, 59, 79, 107, 149, 197, 263, 347, 457, 599, 787, 1031,
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155 1361, 1777, 2333, 3037, 3967, 5167, 6719, 8737, 11369, 14783,
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156 19219, 24989, 32491, 42257, 54941, 71429, 92861, 120721, 156941,
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157 204047, 265271, 344857, 448321, 582821, 757693, 985003, 1280519,
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158 1664681, 2164111, 2813353, 3657361, 4754591, 6180989, 8035301,
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159 10445899, 13579681, 17653589, 22949669, 29834603, 38784989,
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160 50420551, 65546729, 85210757, 110774011, 144006217, 187208107,
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161 243370577, 316381771, 411296309, 534685237, 695090819, 903618083,
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647
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162 1174703521, 1527114613, 1985248999 /* , 2580823717UL, 3355070839UL */
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428
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163 };
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164 /* We've heard of binary search. */
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165 int low, high;
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166 for (low = 0, high = countof (primes) - 1; high - low > 1;)
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167 {
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168 /* Loop Invariant: size < primes [high] */
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169 int mid = (low + high) / 2;
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170 if (primes [mid] < requested_size)
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171 low = mid;
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172 else
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173 high = mid;
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174 }
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175 return primes [high];
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176 }
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177
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178
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179 #if 0 /* I don't think these are needed any more.
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180 If using the general lisp_object_equal_*() functions
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181 causes efficiency problems, these can be resurrected. --ben */
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182 /* equality and hash functions for Lisp strings */
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183 int
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184 lisp_string_equal (Lisp_Object str1, Lisp_Object str2)
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185 {
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186 /* This is wrong anyway. You can't use strcmp() on Lisp strings,
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187 because they can contain zero characters. */
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188 return !strcmp ((char *) XSTRING_DATA (str1), (char *) XSTRING_DATA (str2));
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189 }
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190
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647
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191 static Hash_Code
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428
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192 lisp_string_hash (Lisp_Object obj)
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193 {
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194 return hash_string (XSTRING_DATA (str), XSTRING_LENGTH (str));
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195 }
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196
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197 #endif /* 0 */
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198
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199 static int
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200 lisp_object_eql_equal (Lisp_Object obj1, Lisp_Object obj2)
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201 {
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202 return EQ (obj1, obj2) || (FLOATP (obj1) && internal_equal (obj1, obj2, 0));
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203 }
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204
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647
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205 static Hash_Code
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428
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206 lisp_object_eql_hash (Lisp_Object obj)
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207 {
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208 return FLOATP (obj) ? internal_hash (obj, 0) : LISP_HASH (obj);
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209 }
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210
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211 static int
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212 lisp_object_equal_equal (Lisp_Object obj1, Lisp_Object obj2)
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213 {
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214 return internal_equal (obj1, obj2, 0);
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215 }
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216
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647
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217 static Hash_Code
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428
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218 lisp_object_equal_hash (Lisp_Object obj)
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219 {
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220 return internal_hash (obj, 0);
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221 }
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222
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223
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224 static Lisp_Object
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225 mark_hash_table (Lisp_Object obj)
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226 {
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227 Lisp_Hash_Table *ht = XHASH_TABLE (obj);
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228
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229 /* If the hash table is weak, we don't want to mark the keys and
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230 values (we scan over them after everything else has been marked,
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231 and mark or remove them as necessary). */
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232 if (ht->weakness == HASH_TABLE_NON_WEAK)
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233 {
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234 hentry *e, *sentinel;
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235
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236 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++)
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237 if (!HENTRY_CLEAR_P (e))
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238 {
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239 mark_object (e->key);
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240 mark_object (e->value);
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241 }
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242 }
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243 return Qnil;
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244 }
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245
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246 /* Equality of hash tables. Two hash tables are equal when they are of
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247 the same weakness and test function, they have the same number of
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248 elements, and for each key in the hash table, the values are `equal'.
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249
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250 This is similar to Common Lisp `equalp' of hash tables, with the
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251 difference that CL requires the keys to be compared with the test
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252 function, which we don't do. Doing that would require consing, and
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253 consing is a bad idea in `equal'. Anyway, our method should provide
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254 the same result -- if the keys are not equal according to the test
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255 function, then Fgethash() in hash_table_equal_mapper() will fail. */
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256 static int
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257 hash_table_equal (Lisp_Object hash_table1, Lisp_Object hash_table2, int depth)
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258 {
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259 Lisp_Hash_Table *ht1 = XHASH_TABLE (hash_table1);
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260 Lisp_Hash_Table *ht2 = XHASH_TABLE (hash_table2);
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261 hentry *e, *sentinel;
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262
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263 if ((ht1->test_function != ht2->test_function) ||
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264 (ht1->weakness != ht2->weakness) ||
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265 (ht1->count != ht2->count))
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266 return 0;
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267
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268 depth++;
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269
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270 for (e = ht1->hentries, sentinel = e + ht1->size; e < sentinel; e++)
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271 if (!HENTRY_CLEAR_P (e))
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272 /* Look up the key in the other hash table, and compare the values. */
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273 {
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274 Lisp_Object value_in_other = Fgethash (e->key, hash_table2, Qunbound);
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275 if (UNBOUNDP (value_in_other) ||
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276 !internal_equal (e->value, value_in_other, depth))
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277 return 0; /* Give up */
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278 }
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279
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280 return 1;
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281 }
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442
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282
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283 /* This is not a great hash function, but it _is_ correct and fast.
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284 Examining all entries is too expensive, and examining a random
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285 subset does not yield a correct hash function. */
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647
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286 static Hash_Code
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442
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287 hash_table_hash (Lisp_Object hash_table, int depth)
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288 {
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289 return XHASH_TABLE (hash_table)->count;
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290 }
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291
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428
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292
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293 /* Printing hash tables.
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294
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295 This is non-trivial, because we use a readable structure-style
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296 syntax for hash tables. This means that a typical hash table will be
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297 readably printed in the form of:
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298
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299 #s(hash-table size 2 data (key1 value1 key2 value2))
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300
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301 The supported hash table structure keywords and their values are:
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302 `test' (eql (or nil), eq or equal)
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303 `size' (a natnum or nil)
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304 `rehash-size' (a float)
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305 `rehash-threshold' (a float)
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442
|
306 `weakness' (nil, key, value, key-and-value, or key-or-value)
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428
|
307 `data' (a list)
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|
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308
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430
|
309 If `print-readably' is nil, then a simpler syntax is used, for example
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428
|
310
|
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311 #<hash-table size 2/13 data (key1 value1 key2 value2) 0x874d>
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312
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|
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313 The data is truncated to four pairs, and the rest is shown with
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314 `...'. This printer does not cons. */
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315
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316
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|
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317 /* Print the data of the hash table. This maps through a Lisp
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318 hash table and prints key/value pairs using PRINTCHARFUN. */
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319 static void
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320 print_hash_table_data (Lisp_Hash_Table *ht, Lisp_Object printcharfun)
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321 {
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|
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322 int count = 0;
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323 hentry *e, *sentinel;
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324
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325 write_c_string (" data (", printcharfun);
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326
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327 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++)
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328 if (!HENTRY_CLEAR_P (e))
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329 {
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|
|
330 if (count > 0)
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331 write_c_string (" ", printcharfun);
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|
|
332 if (!print_readably && count > 3)
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|
|
333 {
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|
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334 write_c_string ("...", printcharfun);
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|
335 break;
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|
336 }
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|
|
337 print_internal (e->key, printcharfun, 1);
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|
338 write_c_string (" ", printcharfun);
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|
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339 print_internal (e->value, printcharfun, 1);
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340 count++;
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|
341 }
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|
|
342
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|
|
343 write_c_string (")", printcharfun);
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|
|
344 }
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|
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345
|
|
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346 static void
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|
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347 print_hash_table (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
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|
|
348 {
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|
|
349 Lisp_Hash_Table *ht = XHASH_TABLE (obj);
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|
|
350 char buf[128];
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|
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351
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|
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352 write_c_string (print_readably ? "#s(hash-table" : "#<hash-table",
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|
|
353 printcharfun);
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|
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354
|
|
|
355 /* These checks have a kludgy look to them, but they are safe.
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|
356 Due to nature of hashing, you cannot use arbitrary
|
|
|
357 test functions anyway. */
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|
|
358 if (!ht->test_function)
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|
|
359 write_c_string (" test eq", printcharfun);
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|
|
360 else if (ht->test_function == lisp_object_equal_equal)
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|
|
361 write_c_string (" test equal", printcharfun);
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|
|
362 else if (ht->test_function == lisp_object_eql_equal)
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|
|
363 DO_NOTHING;
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|
|
364 else
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|
|
365 abort ();
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|
|
366
|
|
|
367 if (ht->count || !print_readably)
|
|
|
368 {
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|
|
369 if (print_readably)
|
|
647
|
370 sprintf (buf, " size %ld", (long) ht->count);
|
|
428
|
371 else
|
|
647
|
372 sprintf (buf, " size %ld/%ld", (long) ht->count, (long) ht->size);
|
|
428
|
373 write_c_string (buf, printcharfun);
|
|
|
374 }
|
|
|
375
|
|
|
376 if (ht->weakness != HASH_TABLE_NON_WEAK)
|
|
|
377 {
|
|
|
378 sprintf (buf, " weakness %s",
|
|
442
|
379 (ht->weakness == HASH_TABLE_WEAK ? "key-and-value" :
|
|
|
380 ht->weakness == HASH_TABLE_KEY_WEAK ? "key" :
|
|
|
381 ht->weakness == HASH_TABLE_VALUE_WEAK ? "value" :
|
|
|
382 ht->weakness == HASH_TABLE_KEY_VALUE_WEAK ? "key-or-value" :
|
|
428
|
383 "you-d-better-not-see-this"));
|
|
|
384 write_c_string (buf, printcharfun);
|
|
|
385 }
|
|
|
386
|
|
|
387 if (ht->count)
|
|
|
388 print_hash_table_data (ht, printcharfun);
|
|
|
389
|
|
|
390 if (print_readably)
|
|
|
391 write_c_string (")", printcharfun);
|
|
|
392 else
|
|
|
393 {
|
|
|
394 sprintf (buf, " 0x%x>", ht->header.uid);
|
|
|
395 write_c_string (buf, printcharfun);
|
|
|
396 }
|
|
|
397 }
|
|
|
398
|
|
|
399 static void
|
|
489
|
400 free_hentries (hentry *hentries, size_t size)
|
|
|
401 {
|
|
|
402 #if ERROR_CHECK_HASH_TABLE
|
|
|
403 /* Ensure a crash if other code uses the discarded entries afterwards. */
|
|
|
404 hentry *e, *sentinel;
|
|
|
405
|
|
|
406 for (e = hentries, sentinel = e + size; e < sentinel; e++)
|
|
|
407 * (unsigned long *) e = 0xdeadbeef;
|
|
|
408 #endif
|
|
|
409
|
|
|
410 if (!DUMPEDP (hentries))
|
|
|
411 xfree (hentries);
|
|
|
412 }
|
|
|
413
|
|
|
414 static void
|
|
428
|
415 finalize_hash_table (void *header, int for_disksave)
|
|
|
416 {
|
|
|
417 if (!for_disksave)
|
|
|
418 {
|
|
|
419 Lisp_Hash_Table *ht = (Lisp_Hash_Table *) header;
|
|
489
|
420 free_hentries (ht->hentries, ht->size);
|
|
428
|
421 ht->hentries = 0;
|
|
|
422 }
|
|
|
423 }
|
|
|
424
|
|
|
425 static const struct lrecord_description hentry_description_1[] = {
|
|
440
|
426 { XD_LISP_OBJECT, offsetof (hentry, key) },
|
|
|
427 { XD_LISP_OBJECT, offsetof (hentry, value) },
|
|
428
|
428 { XD_END }
|
|
|
429 };
|
|
|
430
|
|
|
431 static const struct struct_description hentry_description = {
|
|
440
|
432 sizeof (hentry),
|
|
428
|
433 hentry_description_1
|
|
|
434 };
|
|
|
435
|
|
|
436 const struct lrecord_description hash_table_description[] = {
|
|
647
|
437 { XD_ELEMENT_COUNT, offsetof (Lisp_Hash_Table, size) },
|
|
440
|
438 { XD_STRUCT_PTR, offsetof (Lisp_Hash_Table, hentries), XD_INDIRECT(0, 1), &hentry_description },
|
|
|
439 { XD_LO_LINK, offsetof (Lisp_Hash_Table, next_weak) },
|
|
428
|
440 { XD_END }
|
|
|
441 };
|
|
|
442
|
|
|
443 DEFINE_LRECORD_IMPLEMENTATION ("hash-table", hash_table,
|
|
|
444 mark_hash_table, print_hash_table,
|
|
|
445 finalize_hash_table,
|
|
442
|
446 hash_table_equal, hash_table_hash,
|
|
428
|
447 hash_table_description,
|
|
|
448 Lisp_Hash_Table);
|
|
|
449
|
|
|
450 static Lisp_Hash_Table *
|
|
|
451 xhash_table (Lisp_Object hash_table)
|
|
|
452 {
|
|
|
453 if (!gc_in_progress)
|
|
|
454 CHECK_HASH_TABLE (hash_table);
|
|
|
455 check_hash_table_invariants (XHASH_TABLE (hash_table));
|
|
|
456 return XHASH_TABLE (hash_table);
|
|
|
457 }
|
|
|
458
|
|
|
459
|
|
|
460 /************************************************************************/
|
|
|
461 /* Creation of Hash Tables */
|
|
|
462 /************************************************************************/
|
|
|
463
|
|
|
464 /* Creation of hash tables, without error-checking. */
|
|
|
465 static void
|
|
|
466 compute_hash_table_derived_values (Lisp_Hash_Table *ht)
|
|
|
467 {
|
|
647
|
468 ht->rehash_count = (Element_Count)
|
|
438
|
469 ((double) ht->size * ht->rehash_threshold);
|
|
647
|
470 ht->golden_ratio = (Element_Count)
|
|
428
|
471 ((double) ht->size * (.6180339887 / (double) sizeof (Lisp_Object)));
|
|
|
472 }
|
|
|
473
|
|
|
474 Lisp_Object
|
|
450
|
475 make_standard_lisp_hash_table (enum hash_table_test test,
|
|
647
|
476 Element_Count size,
|
|
450
|
477 double rehash_size,
|
|
|
478 double rehash_threshold,
|
|
|
479 enum hash_table_weakness weakness)
|
|
|
480 {
|
|
462
|
481 hash_table_hash_function_t hash_function = 0;
|
|
450
|
482 hash_table_test_function_t test_function = 0;
|
|
|
483
|
|
|
484 switch (test)
|
|
|
485 {
|
|
|
486 case HASH_TABLE_EQ:
|
|
|
487 test_function = 0;
|
|
|
488 hash_function = 0;
|
|
|
489 break;
|
|
|
490
|
|
|
491 case HASH_TABLE_EQL:
|
|
|
492 test_function = lisp_object_eql_equal;
|
|
|
493 hash_function = lisp_object_eql_hash;
|
|
|
494 break;
|
|
|
495
|
|
|
496 case HASH_TABLE_EQUAL:
|
|
|
497 test_function = lisp_object_equal_equal;
|
|
|
498 hash_function = lisp_object_equal_hash;
|
|
|
499 break;
|
|
|
500
|
|
|
501 default:
|
|
|
502 abort ();
|
|
|
503 }
|
|
|
504
|
|
|
505 return make_general_lisp_hash_table (hash_function, test_function,
|
|
|
506 size, rehash_size, rehash_threshold,
|
|
|
507 weakness);
|
|
|
508 }
|
|
|
509
|
|
|
510 Lisp_Object
|
|
|
511 make_general_lisp_hash_table (hash_table_hash_function_t hash_function,
|
|
|
512 hash_table_test_function_t test_function,
|
|
647
|
513 Element_Count size,
|
|
428
|
514 double rehash_size,
|
|
|
515 double rehash_threshold,
|
|
|
516 enum hash_table_weakness weakness)
|
|
|
517 {
|
|
|
518 Lisp_Object hash_table;
|
|
|
519 Lisp_Hash_Table *ht = alloc_lcrecord_type (Lisp_Hash_Table, &lrecord_hash_table);
|
|
|
520
|
|
450
|
521 ht->test_function = test_function;
|
|
|
522 ht->hash_function = hash_function;
|
|
438
|
523 ht->weakness = weakness;
|
|
|
524
|
|
|
525 ht->rehash_size =
|
|
|
526 rehash_size > 1.0 ? rehash_size : HASH_TABLE_DEFAULT_REHASH_SIZE;
|
|
|
527
|
|
|
528 ht->rehash_threshold =
|
|
|
529 rehash_threshold > 0.0 ? rehash_threshold :
|
|
|
530 size > 4096 && !ht->test_function ? 0.7 : 0.6;
|
|
|
531
|
|
428
|
532 if (size < HASH_TABLE_MIN_SIZE)
|
|
|
533 size = HASH_TABLE_MIN_SIZE;
|
|
647
|
534 ht->size = hash_table_size ((Element_Count) (((double) size / ht->rehash_threshold)
|
|
438
|
535 + 1.0));
|
|
428
|
536 ht->count = 0;
|
|
438
|
537
|
|
428
|
538 compute_hash_table_derived_values (ht);
|
|
|
539
|
|
|
540 /* We leave room for one never-occupied sentinel hentry at the end. */
|
|
458
|
541 ht->hentries = xnew_array_and_zero (hentry, ht->size + 1);
|
|
428
|
542
|
|
|
543 XSETHASH_TABLE (hash_table, ht);
|
|
|
544
|
|
|
545 if (weakness == HASH_TABLE_NON_WEAK)
|
|
|
546 ht->next_weak = Qunbound;
|
|
|
547 else
|
|
|
548 ht->next_weak = Vall_weak_hash_tables, Vall_weak_hash_tables = hash_table;
|
|
|
549
|
|
|
550 return hash_table;
|
|
|
551 }
|
|
|
552
|
|
|
553 Lisp_Object
|
|
647
|
554 make_lisp_hash_table (Element_Count size,
|
|
428
|
555 enum hash_table_weakness weakness,
|
|
|
556 enum hash_table_test test)
|
|
|
557 {
|
|
450
|
558 return make_standard_lisp_hash_table (test, size, -1.0, -1.0, weakness);
|
|
428
|
559 }
|
|
|
560
|
|
|
561 /* Pretty reading of hash tables.
|
|
|
562
|
|
|
563 Here we use the existing structures mechanism (which is,
|
|
|
564 unfortunately, pretty cumbersome) for validating and instantiating
|
|
|
565 the hash tables. The idea is that the side-effect of reading a
|
|
|
566 #s(hash-table PLIST) object is creation of a hash table with desired
|
|
|
567 properties, and that the hash table is returned. */
|
|
|
568
|
|
|
569 /* Validation functions: each keyword provides its own validation
|
|
|
570 function. The errors should maybe be continuable, but it is
|
|
|
571 unclear how this would cope with ERRB. */
|
|
|
572 static int
|
|
|
573 hash_table_size_validate (Lisp_Object keyword, Lisp_Object value,
|
|
578
|
574 Error_Behavior errb)
|
|
428
|
575 {
|
|
|
576 if (NATNUMP (value))
|
|
|
577 return 1;
|
|
|
578
|
|
563
|
579 maybe_signal_error_1 (Qwrong_type_argument, list2 (Qnatnump, value),
|
|
428
|
580 Qhash_table, errb);
|
|
|
581 return 0;
|
|
|
582 }
|
|
|
583
|
|
647
|
584 static Element_Count
|
|
428
|
585 decode_hash_table_size (Lisp_Object obj)
|
|
|
586 {
|
|
|
587 return NILP (obj) ? HASH_TABLE_DEFAULT_SIZE : XINT (obj);
|
|
|
588 }
|
|
|
589
|
|
|
590 static int
|
|
|
591 hash_table_weakness_validate (Lisp_Object keyword, Lisp_Object value,
|
|
578
|
592 Error_Behavior errb)
|
|
428
|
593 {
|
|
442
|
594 if (EQ (value, Qnil)) return 1;
|
|
|
595 if (EQ (value, Qt)) return 1;
|
|
|
596 if (EQ (value, Qkey)) return 1;
|
|
|
597 if (EQ (value, Qkey_and_value)) return 1;
|
|
|
598 if (EQ (value, Qkey_or_value)) return 1;
|
|
|
599 if (EQ (value, Qvalue)) return 1;
|
|
428
|
600
|
|
|
601 /* Following values are obsolete as of 19990901 in xemacs-21.2 */
|
|
442
|
602 if (EQ (value, Qnon_weak)) return 1;
|
|
|
603 if (EQ (value, Qweak)) return 1;
|
|
|
604 if (EQ (value, Qkey_weak)) return 1;
|
|
|
605 if (EQ (value, Qkey_or_value_weak)) return 1;
|
|
|
606 if (EQ (value, Qvalue_weak)) return 1;
|
|
428
|
607
|
|
563
|
608 maybe_invalid_constant ("Invalid hash table weakness",
|
|
428
|
609 value, Qhash_table, errb);
|
|
|
610 return 0;
|
|
|
611 }
|
|
|
612
|
|
|
613 static enum hash_table_weakness
|
|
|
614 decode_hash_table_weakness (Lisp_Object obj)
|
|
|
615 {
|
|
442
|
616 if (EQ (obj, Qnil)) return HASH_TABLE_NON_WEAK;
|
|
|
617 if (EQ (obj, Qt)) return HASH_TABLE_WEAK;
|
|
|
618 if (EQ (obj, Qkey_and_value)) return HASH_TABLE_WEAK;
|
|
|
619 if (EQ (obj, Qkey)) return HASH_TABLE_KEY_WEAK;
|
|
|
620 if (EQ (obj, Qkey_or_value)) return HASH_TABLE_KEY_VALUE_WEAK;
|
|
|
621 if (EQ (obj, Qvalue)) return HASH_TABLE_VALUE_WEAK;
|
|
428
|
622
|
|
|
623 /* Following values are obsolete as of 19990901 in xemacs-21.2 */
|
|
442
|
624 if (EQ (obj, Qnon_weak)) return HASH_TABLE_NON_WEAK;
|
|
|
625 if (EQ (obj, Qweak)) return HASH_TABLE_WEAK;
|
|
|
626 if (EQ (obj, Qkey_weak)) return HASH_TABLE_KEY_WEAK;
|
|
|
627 if (EQ (obj, Qkey_or_value_weak)) return HASH_TABLE_KEY_VALUE_WEAK;
|
|
|
628 if (EQ (obj, Qvalue_weak)) return HASH_TABLE_VALUE_WEAK;
|
|
428
|
629
|
|
563
|
630 invalid_constant ("Invalid hash table weakness", obj);
|
|
428
|
631 return HASH_TABLE_NON_WEAK; /* not reached */
|
|
|
632 }
|
|
|
633
|
|
|
634 static int
|
|
|
635 hash_table_test_validate (Lisp_Object keyword, Lisp_Object value,
|
|
578
|
636 Error_Behavior errb)
|
|
428
|
637 {
|
|
|
638 if (EQ (value, Qnil)) return 1;
|
|
|
639 if (EQ (value, Qeq)) return 1;
|
|
|
640 if (EQ (value, Qequal)) return 1;
|
|
|
641 if (EQ (value, Qeql)) return 1;
|
|
|
642
|
|
563
|
643 maybe_invalid_constant ("Invalid hash table test",
|
|
428
|
644 value, Qhash_table, errb);
|
|
|
645 return 0;
|
|
|
646 }
|
|
|
647
|
|
|
648 static enum hash_table_test
|
|
|
649 decode_hash_table_test (Lisp_Object obj)
|
|
|
650 {
|
|
|
651 if (EQ (obj, Qnil)) return HASH_TABLE_EQL;
|
|
|
652 if (EQ (obj, Qeq)) return HASH_TABLE_EQ;
|
|
|
653 if (EQ (obj, Qequal)) return HASH_TABLE_EQUAL;
|
|
|
654 if (EQ (obj, Qeql)) return HASH_TABLE_EQL;
|
|
|
655
|
|
563
|
656 invalid_constant ("Invalid hash table test", obj);
|
|
428
|
657 return HASH_TABLE_EQ; /* not reached */
|
|
|
658 }
|
|
|
659
|
|
|
660 static int
|
|
|
661 hash_table_rehash_size_validate (Lisp_Object keyword, Lisp_Object value,
|
|
578
|
662 Error_Behavior errb)
|
|
428
|
663 {
|
|
|
664 if (!FLOATP (value))
|
|
|
665 {
|
|
563
|
666 maybe_signal_error_1 (Qwrong_type_argument, list2 (Qfloatp, value),
|
|
428
|
667 Qhash_table, errb);
|
|
|
668 return 0;
|
|
|
669 }
|
|
|
670
|
|
|
671 {
|
|
|
672 double rehash_size = XFLOAT_DATA (value);
|
|
|
673 if (rehash_size <= 1.0)
|
|
|
674 {
|
|
563
|
675 maybe_invalid_argument
|
|
428
|
676 ("Hash table rehash size must be greater than 1.0",
|
|
|
677 value, Qhash_table, errb);
|
|
|
678 return 0;
|
|
|
679 }
|
|
|
680 }
|
|
|
681
|
|
|
682 return 1;
|
|
|
683 }
|
|
|
684
|
|
|
685 static double
|
|
|
686 decode_hash_table_rehash_size (Lisp_Object rehash_size)
|
|
|
687 {
|
|
|
688 return NILP (rehash_size) ? -1.0 : XFLOAT_DATA (rehash_size);
|
|
|
689 }
|
|
|
690
|
|
|
691 static int
|
|
|
692 hash_table_rehash_threshold_validate (Lisp_Object keyword, Lisp_Object value,
|
|
578
|
693 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_threshold = XFLOAT_DATA (value);
|
|
|
704 if (rehash_threshold <= 0.0 || rehash_threshold >= 1.0)
|
|
|
705 {
|
|
563
|
706 maybe_invalid_argument
|
|
428
|
707 ("Hash table rehash threshold must be between 0.0 and 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_threshold (Lisp_Object rehash_threshold)
|
|
|
718 {
|
|
|
719 return NILP (rehash_threshold) ? -1.0 : XFLOAT_DATA (rehash_threshold);
|
|
|
720 }
|
|
|
721
|
|
|
722 static int
|
|
|
723 hash_table_data_validate (Lisp_Object keyword, Lisp_Object value,
|
|
578
|
724 Error_Behavior errb)
|
|
428
|
725 {
|
|
|
726 int len;
|
|
|
727
|
|
|
728 GET_EXTERNAL_LIST_LENGTH (value, len);
|
|
|
729
|
|
|
730 if (len & 1)
|
|
|
731 {
|
|
563
|
732 maybe_sferror
|
|
428
|
733 ("Hash table data must have alternating key/value pairs",
|
|
|
734 value, Qhash_table, errb);
|
|
|
735 return 0;
|
|
|
736 }
|
|
|
737 return 1;
|
|
|
738 }
|
|
|
739
|
|
|
740 /* The actual instantiation of a hash table. This does practically no
|
|
|
741 error checking, because it relies on the fact that the paranoid
|
|
|
742 functions above have error-checked everything to the last details.
|
|
|
743 If this assumption is wrong, we will get a crash immediately (with
|
|
|
744 error-checking compiled in), and we'll know if there is a bug in
|
|
|
745 the structure mechanism. So there. */
|
|
|
746 static Lisp_Object
|
|
|
747 hash_table_instantiate (Lisp_Object plist)
|
|
|
748 {
|
|
|
749 Lisp_Object hash_table;
|
|
|
750 Lisp_Object test = Qnil;
|
|
|
751 Lisp_Object size = Qnil;
|
|
|
752 Lisp_Object rehash_size = Qnil;
|
|
|
753 Lisp_Object rehash_threshold = Qnil;
|
|
|
754 Lisp_Object weakness = Qnil;
|
|
|
755 Lisp_Object data = Qnil;
|
|
|
756
|
|
|
757 while (!NILP (plist))
|
|
|
758 {
|
|
|
759 Lisp_Object key, value;
|
|
|
760 key = XCAR (plist); plist = XCDR (plist);
|
|
|
761 value = XCAR (plist); plist = XCDR (plist);
|
|
|
762
|
|
|
763 if (EQ (key, Qtest)) test = value;
|
|
|
764 else if (EQ (key, Qsize)) size = value;
|
|
|
765 else if (EQ (key, Qrehash_size)) rehash_size = value;
|
|
|
766 else if (EQ (key, Qrehash_threshold)) rehash_threshold = value;
|
|
|
767 else if (EQ (key, Qweakness)) weakness = value;
|
|
|
768 else if (EQ (key, Qdata)) data = value;
|
|
|
769 else if (EQ (key, Qtype))/*obsolete*/ weakness = value;
|
|
|
770 else
|
|
|
771 abort ();
|
|
|
772 }
|
|
|
773
|
|
|
774 /* Create the hash table. */
|
|
450
|
775 hash_table = make_standard_lisp_hash_table
|
|
428
|
776 (decode_hash_table_test (test),
|
|
|
777 decode_hash_table_size (size),
|
|
|
778 decode_hash_table_rehash_size (rehash_size),
|
|
|
779 decode_hash_table_rehash_threshold (rehash_threshold),
|
|
|
780 decode_hash_table_weakness (weakness));
|
|
|
781
|
|
|
782 /* I'm not sure whether this can GC, but better safe than sorry. */
|
|
|
783 {
|
|
|
784 struct gcpro gcpro1;
|
|
|
785 GCPRO1 (hash_table);
|
|
|
786
|
|
|
787 /* And fill it with data. */
|
|
|
788 while (!NILP (data))
|
|
|
789 {
|
|
|
790 Lisp_Object key, value;
|
|
|
791 key = XCAR (data); data = XCDR (data);
|
|
|
792 value = XCAR (data); data = XCDR (data);
|
|
|
793 Fputhash (key, value, hash_table);
|
|
|
794 }
|
|
|
795 UNGCPRO;
|
|
|
796 }
|
|
|
797
|
|
|
798 return hash_table;
|
|
|
799 }
|
|
|
800
|
|
|
801 static void
|
|
|
802 structure_type_create_hash_table_structure_name (Lisp_Object structure_name)
|
|
|
803 {
|
|
|
804 struct structure_type *st;
|
|
|
805
|
|
|
806 st = define_structure_type (structure_name, 0, hash_table_instantiate);
|
|
|
807 define_structure_type_keyword (st, Qtest, hash_table_test_validate);
|
|
|
808 define_structure_type_keyword (st, Qsize, hash_table_size_validate);
|
|
|
809 define_structure_type_keyword (st, Qrehash_size, hash_table_rehash_size_validate);
|
|
|
810 define_structure_type_keyword (st, Qrehash_threshold, hash_table_rehash_threshold_validate);
|
|
|
811 define_structure_type_keyword (st, Qweakness, hash_table_weakness_validate);
|
|
|
812 define_structure_type_keyword (st, Qdata, hash_table_data_validate);
|
|
|
813
|
|
|
814 /* obsolete as of 19990901 in xemacs-21.2 */
|
|
|
815 define_structure_type_keyword (st, Qtype, hash_table_weakness_validate);
|
|
|
816 }
|
|
|
817
|
|
|
818 /* Create a built-in Lisp structure type named `hash-table'.
|
|
|
819 We make #s(hashtable ...) equivalent to #s(hash-table ...),
|
|
|
820 for backward compatibility.
|
|
|
821 This is called from emacs.c. */
|
|
|
822 void
|
|
|
823 structure_type_create_hash_table (void)
|
|
|
824 {
|
|
|
825 structure_type_create_hash_table_structure_name (Qhash_table);
|
|
|
826 structure_type_create_hash_table_structure_name (Qhashtable); /* compat */
|
|
|
827 }
|
|
|
828
|
|
|
829
|
|
|
830 /************************************************************************/
|
|
|
831 /* Definition of Lisp-visible methods */
|
|
|
832 /************************************************************************/
|
|
|
833
|
|
|
834 DEFUN ("hash-table-p", Fhash_table_p, 1, 1, 0, /*
|
|
|
835 Return t if OBJECT is a hash table, else nil.
|
|
|
836 */
|
|
|
837 (object))
|
|
|
838 {
|
|
|
839 return HASH_TABLEP (object) ? Qt : Qnil;
|
|
|
840 }
|
|
|
841
|
|
|
842 DEFUN ("make-hash-table", Fmake_hash_table, 0, MANY, 0, /*
|
|
|
843 Return a new empty hash table object.
|
|
|
844 Use Common Lisp style keywords to specify hash table properties.
|
|
|
845 (make-hash-table &key test size rehash-size rehash-threshold weakness)
|
|
|
846
|
|
|
847 Keyword :test can be `eq', `eql' (default) or `equal'.
|
|
|
848 Comparison between keys is done using this function.
|
|
|
849 If speed is important, consider using `eq'.
|
|
|
850 When storing strings in the hash table, you will likely need to use `equal'.
|
|
|
851
|
|
|
852 Keyword :size specifies the number of keys likely to be inserted.
|
|
|
853 This number of entries can be inserted without enlarging the hash table.
|
|
|
854
|
|
|
855 Keyword :rehash-size must be a float greater than 1.0, and specifies
|
|
|
856 the factor by which to increase the size of the hash table when enlarging.
|
|
|
857
|
|
|
858 Keyword :rehash-threshold must be a float between 0.0 and 1.0,
|
|
|
859 and specifies the load factor of the hash table which triggers enlarging.
|
|
|
860
|
|
442
|
861 Non-standard keyword :weakness can be `nil' (default), `t', `key-and-value',
|
|
|
862 `key', `value' or `key-or-value'. `t' is an alias for `key-and-value'.
|
|
428
|
863
|
|
442
|
864 A key-and-value-weak hash table, also known as a fully-weak or simply
|
|
|
865 as a weak hash table, is one whose pointers do not count as GC
|
|
|
866 referents: for any key-value pair in the hash table, if the only
|
|
|
867 remaining pointer to either the key or the value is in a weak hash
|
|
|
868 table, then the pair will be removed from the hash table, and the key
|
|
|
869 and value collected. A non-weak hash table (or any other pointer)
|
|
|
870 would prevent the object from being collected.
|
|
428
|
871
|
|
|
872 A key-weak hash table is similar to a fully-weak hash table except that
|
|
|
873 a key-value pair will be removed only if the key remains unmarked
|
|
|
874 outside of weak hash tables. The pair will remain in the hash table if
|
|
|
875 the key is pointed to by something other than a weak hash table, even
|
|
|
876 if the value is not.
|
|
|
877
|
|
|
878 A value-weak hash table is similar to a fully-weak hash table except
|
|
|
879 that a key-value pair will be removed only if the value remains
|
|
|
880 unmarked outside of weak hash tables. The pair will remain in the
|
|
|
881 hash table if the value is pointed to by something other than a weak
|
|
|
882 hash table, even if the key is not.
|
|
442
|
883
|
|
|
884 A key-or-value-weak hash table is similar to a fully-weak hash table except
|
|
|
885 that a key-value pair will be removed only if the value and the key remain
|
|
|
886 unmarked outside of weak hash tables. The pair will remain in the
|
|
|
887 hash table if the value or key are pointed to by something other than a weak
|
|
|
888 hash table, even if the other is not.
|
|
428
|
889 */
|
|
|
890 (int nargs, Lisp_Object *args))
|
|
|
891 {
|
|
|
892 int i = 0;
|
|
|
893 Lisp_Object test = Qnil;
|
|
|
894 Lisp_Object size = Qnil;
|
|
|
895 Lisp_Object rehash_size = Qnil;
|
|
|
896 Lisp_Object rehash_threshold = Qnil;
|
|
|
897 Lisp_Object weakness = Qnil;
|
|
|
898
|
|
|
899 while (i + 1 < nargs)
|
|
|
900 {
|
|
|
901 Lisp_Object keyword = args[i++];
|
|
|
902 Lisp_Object value = args[i++];
|
|
|
903
|
|
|
904 if (EQ (keyword, Q_test)) test = value;
|
|
|
905 else if (EQ (keyword, Q_size)) size = value;
|
|
|
906 else if (EQ (keyword, Q_rehash_size)) rehash_size = value;
|
|
|
907 else if (EQ (keyword, Q_rehash_threshold)) rehash_threshold = value;
|
|
|
908 else if (EQ (keyword, Q_weakness)) weakness = value;
|
|
|
909 else if (EQ (keyword, Q_type))/*obsolete*/ weakness = value;
|
|
563
|
910 else invalid_constant ("Invalid hash table property keyword", keyword);
|
|
428
|
911 }
|
|
|
912
|
|
|
913 if (i < nargs)
|
|
563
|
914 sferror ("Hash table property requires a value", args[i]);
|
|
428
|
915
|
|
|
916 #define VALIDATE_VAR(var) \
|
|
|
917 if (!NILP (var)) hash_table_##var##_validate (Q##var, var, ERROR_ME);
|
|
|
918
|
|
|
919 VALIDATE_VAR (test);
|
|
|
920 VALIDATE_VAR (size);
|
|
|
921 VALIDATE_VAR (rehash_size);
|
|
|
922 VALIDATE_VAR (rehash_threshold);
|
|
|
923 VALIDATE_VAR (weakness);
|
|
|
924
|
|
450
|
925 return make_standard_lisp_hash_table
|
|
428
|
926 (decode_hash_table_test (test),
|
|
|
927 decode_hash_table_size (size),
|
|
|
928 decode_hash_table_rehash_size (rehash_size),
|
|
|
929 decode_hash_table_rehash_threshold (rehash_threshold),
|
|
|
930 decode_hash_table_weakness (weakness));
|
|
|
931 }
|
|
|
932
|
|
|
933 DEFUN ("copy-hash-table", Fcopy_hash_table, 1, 1, 0, /*
|
|
|
934 Return a new hash table containing the same keys and values as HASH-TABLE.
|
|
|
935 The keys and values will not themselves be copied.
|
|
|
936 */
|
|
|
937 (hash_table))
|
|
|
938 {
|
|
442
|
939 const Lisp_Hash_Table *ht_old = xhash_table (hash_table);
|
|
428
|
940 Lisp_Hash_Table *ht = alloc_lcrecord_type (Lisp_Hash_Table, &lrecord_hash_table);
|
|
|
941
|
|
|
942 copy_lcrecord (ht, ht_old);
|
|
|
943
|
|
|
944 ht->hentries = xnew_array (hentry, ht_old->size + 1);
|
|
|
945 memcpy (ht->hentries, ht_old->hentries, (ht_old->size + 1) * sizeof (hentry));
|
|
|
946
|
|
|
947 XSETHASH_TABLE (hash_table, ht);
|
|
|
948
|
|
|
949 if (! EQ (ht->next_weak, Qunbound))
|
|
|
950 {
|
|
|
951 ht->next_weak = Vall_weak_hash_tables;
|
|
|
952 Vall_weak_hash_tables = hash_table;
|
|
|
953 }
|
|
|
954
|
|
|
955 return hash_table;
|
|
|
956 }
|
|
|
957
|
|
|
958 static void
|
|
647
|
959 resize_hash_table (Lisp_Hash_Table *ht, Element_Count new_size)
|
|
428
|
960 {
|
|
440
|
961 hentry *old_entries, *new_entries, *sentinel, *e;
|
|
647
|
962 Element_Count old_size;
|
|
428
|
963
|
|
|
964 old_size = ht->size;
|
|
|
965 ht->size = new_size;
|
|
|
966
|
|
|
967 old_entries = ht->hentries;
|
|
|
968
|
|
440
|
969 ht->hentries = xnew_array_and_zero (hentry, new_size + 1);
|
|
428
|
970 new_entries = ht->hentries;
|
|
|
971
|
|
|
972 compute_hash_table_derived_values (ht);
|
|
|
973
|
|
440
|
974 for (e = old_entries, sentinel = e + old_size; e < sentinel; e++)
|
|
428
|
975 if (!HENTRY_CLEAR_P (e))
|
|
|
976 {
|
|
|
977 hentry *probe = new_entries + HASH_CODE (e->key, ht);
|
|
|
978 LINEAR_PROBING_LOOP (probe, new_entries, new_size)
|
|
|
979 ;
|
|
|
980 *probe = *e;
|
|
|
981 }
|
|
|
982
|
|
489
|
983 free_hentries (old_entries, old_size);
|
|
428
|
984 }
|
|
|
985
|
|
440
|
986 /* After a hash table has been saved to disk and later restored by the
|
|
|
987 portable dumper, it contains the same objects, but their addresses
|
|
|
988 and thus their HASH_CODEs have changed. */
|
|
428
|
989 void
|
|
440
|
990 pdump_reorganize_hash_table (Lisp_Object hash_table)
|
|
428
|
991 {
|
|
442
|
992 const Lisp_Hash_Table *ht = xhash_table (hash_table);
|
|
440
|
993 hentry *new_entries = xnew_array_and_zero (hentry, ht->size + 1);
|
|
|
994 hentry *e, *sentinel;
|
|
|
995
|
|
|
996 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++)
|
|
|
997 if (!HENTRY_CLEAR_P (e))
|
|
|
998 {
|
|
|
999 hentry *probe = new_entries + HASH_CODE (e->key, ht);
|
|
|
1000 LINEAR_PROBING_LOOP (probe, new_entries, ht->size)
|
|
|
1001 ;
|
|
|
1002 *probe = *e;
|
|
|
1003 }
|
|
|
1004
|
|
|
1005 memcpy (ht->hentries, new_entries, ht->size * sizeof (hentry));
|
|
|
1006
|
|
|
1007 xfree (new_entries);
|
|
428
|
1008 }
|
|
|
1009
|
|
|
1010 static void
|
|
|
1011 enlarge_hash_table (Lisp_Hash_Table *ht)
|
|
|
1012 {
|
|
647
|
1013 Element_Count new_size =
|
|
|
1014 hash_table_size ((Element_Count) ((double) ht->size * ht->rehash_size));
|
|
428
|
1015 resize_hash_table (ht, new_size);
|
|
|
1016 }
|
|
|
1017
|
|
|
1018 static hentry *
|
|
442
|
1019 find_hentry (Lisp_Object key, const Lisp_Hash_Table *ht)
|
|
428
|
1020 {
|
|
|
1021 hash_table_test_function_t test_function = ht->test_function;
|
|
|
1022 hentry *entries = ht->hentries;
|
|
|
1023 hentry *probe = entries + HASH_CODE (key, ht);
|
|
|
1024
|
|
|
1025 LINEAR_PROBING_LOOP (probe, entries, ht->size)
|
|
|
1026 if (KEYS_EQUAL_P (probe->key, key, test_function))
|
|
|
1027 break;
|
|
|
1028
|
|
|
1029 return probe;
|
|
|
1030 }
|
|
|
1031
|
|
|
1032 DEFUN ("gethash", Fgethash, 2, 3, 0, /*
|
|
|
1033 Find hash value for KEY in HASH-TABLE.
|
|
|
1034 If there is no corresponding value, return DEFAULT (which defaults to nil).
|
|
|
1035 */
|
|
|
1036 (key, hash_table, default_))
|
|
|
1037 {
|
|
442
|
1038 const Lisp_Hash_Table *ht = xhash_table (hash_table);
|
|
428
|
1039 hentry *e = find_hentry (key, ht);
|
|
|
1040
|
|
|
1041 return HENTRY_CLEAR_P (e) ? default_ : e->value;
|
|
|
1042 }
|
|
|
1043
|
|
|
1044 DEFUN ("puthash", Fputhash, 3, 3, 0, /*
|
|
|
1045 Hash KEY to VALUE in HASH-TABLE.
|
|
|
1046 */
|
|
|
1047 (key, value, hash_table))
|
|
|
1048 {
|
|
|
1049 Lisp_Hash_Table *ht = xhash_table (hash_table);
|
|
|
1050 hentry *e = find_hentry (key, ht);
|
|
|
1051
|
|
|
1052 if (!HENTRY_CLEAR_P (e))
|
|
|
1053 return e->value = value;
|
|
|
1054
|
|
|
1055 e->key = key;
|
|
|
1056 e->value = value;
|
|
|
1057
|
|
|
1058 if (++ht->count >= ht->rehash_count)
|
|
|
1059 enlarge_hash_table (ht);
|
|
|
1060
|
|
|
1061 return value;
|
|
|
1062 }
|
|
|
1063
|
|
|
1064 /* Remove hentry pointed at by PROBE.
|
|
|
1065 Subsequent entries are removed and reinserted.
|
|
|
1066 We don't use tombstones - too wasteful. */
|
|
|
1067 static void
|
|
|
1068 remhash_1 (Lisp_Hash_Table *ht, hentry *entries, hentry *probe)
|
|
|
1069 {
|
|
647
|
1070 Element_Count size = ht->size;
|
|
428
|
1071 CLEAR_HENTRY (probe);
|
|
|
1072 probe++;
|
|
|
1073 ht->count--;
|
|
|
1074
|
|
|
1075 LINEAR_PROBING_LOOP (probe, entries, size)
|
|
|
1076 {
|
|
|
1077 Lisp_Object key = probe->key;
|
|
|
1078 hentry *probe2 = entries + HASH_CODE (key, ht);
|
|
|
1079 LINEAR_PROBING_LOOP (probe2, entries, size)
|
|
|
1080 if (EQ (probe2->key, key))
|
|
|
1081 /* hentry at probe doesn't need to move. */
|
|
|
1082 goto continue_outer_loop;
|
|
|
1083 /* Move hentry from probe to new home at probe2. */
|
|
|
1084 *probe2 = *probe;
|
|
|
1085 CLEAR_HENTRY (probe);
|
|
|
1086 continue_outer_loop: continue;
|
|
|
1087 }
|
|
|
1088 }
|
|
|
1089
|
|
|
1090 DEFUN ("remhash", Fremhash, 2, 2, 0, /*
|
|
|
1091 Remove the entry for KEY from HASH-TABLE.
|
|
|
1092 Do nothing if there is no entry for KEY in HASH-TABLE.
|
|
617
|
1093 Return non-nil if an entry was removed.
|
|
428
|
1094 */
|
|
|
1095 (key, hash_table))
|
|
|
1096 {
|
|
|
1097 Lisp_Hash_Table *ht = xhash_table (hash_table);
|
|
|
1098 hentry *e = find_hentry (key, ht);
|
|
|
1099
|
|
|
1100 if (HENTRY_CLEAR_P (e))
|
|
|
1101 return Qnil;
|
|
|
1102
|
|
|
1103 remhash_1 (ht, ht->hentries, e);
|
|
|
1104 return Qt;
|
|
|
1105 }
|
|
|
1106
|
|
|
1107 DEFUN ("clrhash", Fclrhash, 1, 1, 0, /*
|
|
|
1108 Remove all entries from HASH-TABLE, leaving it empty.
|
|
|
1109 */
|
|
|
1110 (hash_table))
|
|
|
1111 {
|
|
|
1112 Lisp_Hash_Table *ht = xhash_table (hash_table);
|
|
|
1113 hentry *e, *sentinel;
|
|
|
1114
|
|
|
1115 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++)
|
|
|
1116 CLEAR_HENTRY (e);
|
|
|
1117 ht->count = 0;
|
|
|
1118
|
|
|
1119 return hash_table;
|
|
|
1120 }
|
|
|
1121
|
|
|
1122 /************************************************************************/
|
|
|
1123 /* Accessor Functions */
|
|
|
1124 /************************************************************************/
|
|
|
1125
|
|
|
1126 DEFUN ("hash-table-count", Fhash_table_count, 1, 1, 0, /*
|
|
|
1127 Return the number of entries in HASH-TABLE.
|
|
|
1128 */
|
|
|
1129 (hash_table))
|
|
|
1130 {
|
|
|
1131 return make_int (xhash_table (hash_table)->count);
|
|
|
1132 }
|
|
|
1133
|
|
|
1134 DEFUN ("hash-table-test", Fhash_table_test, 1, 1, 0, /*
|
|
|
1135 Return the test function of HASH-TABLE.
|
|
|
1136 This can be one of `eq', `eql' or `equal'.
|
|
|
1137 */
|
|
|
1138 (hash_table))
|
|
|
1139 {
|
|
|
1140 hash_table_test_function_t fun = xhash_table (hash_table)->test_function;
|
|
|
1141
|
|
|
1142 return (fun == lisp_object_eql_equal ? Qeql :
|
|
|
1143 fun == lisp_object_equal_equal ? Qequal :
|
|
|
1144 Qeq);
|
|
|
1145 }
|
|
|
1146
|
|
|
1147 DEFUN ("hash-table-size", Fhash_table_size, 1, 1, 0, /*
|
|
|
1148 Return the size of HASH-TABLE.
|
|
|
1149 This is the current number of slots in HASH-TABLE, whether occupied or not.
|
|
|
1150 */
|
|
|
1151 (hash_table))
|
|
|
1152 {
|
|
|
1153 return make_int (xhash_table (hash_table)->size);
|
|
|
1154 }
|
|
|
1155
|
|
|
1156 DEFUN ("hash-table-rehash-size", Fhash_table_rehash_size, 1, 1, 0, /*
|
|
|
1157 Return the current rehash size of HASH-TABLE.
|
|
|
1158 This is a float greater than 1.0; the factor by which HASH-TABLE
|
|
|
1159 is enlarged when the rehash threshold is exceeded.
|
|
|
1160 */
|
|
|
1161 (hash_table))
|
|
|
1162 {
|
|
|
1163 return make_float (xhash_table (hash_table)->rehash_size);
|
|
|
1164 }
|
|
|
1165
|
|
|
1166 DEFUN ("hash-table-rehash-threshold", Fhash_table_rehash_threshold, 1, 1, 0, /*
|
|
|
1167 Return the current rehash threshold of HASH-TABLE.
|
|
|
1168 This is a float between 0.0 and 1.0; the maximum `load factor' of HASH-TABLE,
|
|
|
1169 beyond which the HASH-TABLE is enlarged by rehashing.
|
|
|
1170 */
|
|
|
1171 (hash_table))
|
|
|
1172 {
|
|
438
|
1173 return make_float (xhash_table (hash_table)->rehash_threshold);
|
|
428
|
1174 }
|
|
|
1175
|
|
|
1176 DEFUN ("hash-table-weakness", Fhash_table_weakness, 1, 1, 0, /*
|
|
|
1177 Return the weakness of HASH-TABLE.
|
|
442
|
1178 This can be one of `nil', `key-and-value', `key-or-value', `key' or `value'.
|
|
428
|
1179 */
|
|
|
1180 (hash_table))
|
|
|
1181 {
|
|
|
1182 switch (xhash_table (hash_table)->weakness)
|
|
|
1183 {
|
|
442
|
1184 case HASH_TABLE_WEAK: return Qkey_and_value;
|
|
|
1185 case HASH_TABLE_KEY_WEAK: return Qkey;
|
|
|
1186 case HASH_TABLE_KEY_VALUE_WEAK: return Qkey_or_value;
|
|
|
1187 case HASH_TABLE_VALUE_WEAK: return Qvalue;
|
|
|
1188 default: return Qnil;
|
|
428
|
1189 }
|
|
|
1190 }
|
|
|
1191
|
|
|
1192 /* obsolete as of 19990901 in xemacs-21.2 */
|
|
|
1193 DEFUN ("hash-table-type", Fhash_table_type, 1, 1, 0, /*
|
|
|
1194 Return the type of HASH-TABLE.
|
|
|
1195 This can be one of `non-weak', `weak', `key-weak' or `value-weak'.
|
|
|
1196 */
|
|
|
1197 (hash_table))
|
|
|
1198 {
|
|
|
1199 switch (xhash_table (hash_table)->weakness)
|
|
|
1200 {
|
|
442
|
1201 case HASH_TABLE_WEAK: return Qweak;
|
|
|
1202 case HASH_TABLE_KEY_WEAK: return Qkey_weak;
|
|
|
1203 case HASH_TABLE_KEY_VALUE_WEAK: return Qkey_or_value_weak;
|
|
|
1204 case HASH_TABLE_VALUE_WEAK: return Qvalue_weak;
|
|
|
1205 default: return Qnon_weak;
|
|
428
|
1206 }
|
|
|
1207 }
|
|
|
1208
|
|
|
1209 /************************************************************************/
|
|
|
1210 /* Mapping Functions */
|
|
|
1211 /************************************************************************/
|
|
489
|
1212
|
|
|
1213 /* We need to be careful when mapping over hash tables because the
|
|
|
1214 hash table might be modified during the mapping operation:
|
|
|
1215 - by the mapping function
|
|
|
1216 - by gc (if the hash table is weak)
|
|
|
1217
|
|
|
1218 So we make a copy of the hentries at the beginning of the mapping
|
|
497
|
1219 operation, and iterate over the copy. Naturally, this is
|
|
|
1220 expensive, but not as expensive as you might think, because no
|
|
|
1221 actual memory has to be collected by our notoriously inefficient
|
|
|
1222 GC; we use an unwind-protect instead to free the memory directly.
|
|
|
1223
|
|
|
1224 We could avoid the copying by having the hash table modifiers
|
|
|
1225 puthash and remhash check for currently active mapping functions.
|
|
|
1226 Disadvantages: it's hard to get right, and IMO hash mapping
|
|
|
1227 functions are basically rare, and no extra space in the hash table
|
|
|
1228 object and no extra cpu in puthash or remhash should be wasted to
|
|
|
1229 make maphash 3% faster. From a design point of view, the basic
|
|
|
1230 functions gethash, puthash and remhash should be implementable
|
|
|
1231 without having to think about maphash.
|
|
|
1232
|
|
|
1233 Note: We don't (yet) have Common Lisp's with-hash-table-iterator.
|
|
|
1234 If you implement this naively, you cannot have more than one
|
|
|
1235 concurrently active iterator over the same hash table. The `each'
|
|
|
1236 function in perl has this limitation.
|
|
|
1237
|
|
|
1238 Note: We GCPRO memory on the heap, not on the stack. There is no
|
|
|
1239 obvious reason why this is bad, but as of this writing this is the
|
|
|
1240 only known occurrence of this technique in the code.
|
|
504
|
1241
|
|
|
1242 -- Martin
|
|
|
1243 */
|
|
|
1244
|
|
|
1245 /* Ben disagrees with the "copying hentries" design, and says:
|
|
|
1246
|
|
|
1247 Another solution is the same as I've already proposed -- when
|
|
|
1248 mapping, mark the table as "change-unsafe", and in this case, use a
|
|
|
1249 secondary table to maintain changes. this could be basically a
|
|
|
1250 standard hash table, but with entries only for added or deleted
|
|
|
1251 entries in the primary table, and a marker like Qunbound to
|
|
|
1252 indicate a deleted entry. puthash, gethash and remhash need a
|
|
|
1253 single extra check for this secondary table -- totally
|
|
|
1254 insignificant speedwise. if you really cared about making
|
|
|
1255 recursive maphashes completely correct, you'd have to do a bit of
|
|
|
1256 extra work here -- when maphashing, if the secondary table exists,
|
|
|
1257 make a copy of it, and use the copy in conjunction with the primary
|
|
|
1258 table when mapping. the advantages of this are
|
|
|
1259
|
|
|
1260 [a] easy to demonstrate correct, even with weak hashtables.
|
|
|
1261
|
|
|
1262 [b] no extra overhead in the general maphash case -- only when you
|
|
|
1263 modify the table while maphashing, and even then the overhead is
|
|
|
1264 very small.
|
|
497
|
1265 */
|
|
|
1266
|
|
489
|
1267 static Lisp_Object
|
|
|
1268 maphash_unwind (Lisp_Object unwind_obj)
|
|
|
1269 {
|
|
|
1270 void *ptr = (void *) get_opaque_ptr (unwind_obj);
|
|
|
1271 xfree (ptr);
|
|
|
1272 free_opaque_ptr (unwind_obj);
|
|
|
1273 return Qnil;
|
|
|
1274 }
|
|
|
1275
|
|
|
1276 /* Return a malloced array of alternating key/value pairs from HT. */
|
|
|
1277 static Lisp_Object *
|
|
|
1278 copy_compress_hentries (const Lisp_Hash_Table *ht)
|
|
|
1279 {
|
|
|
1280 Lisp_Object * const objs =
|
|
|
1281 /* If the hash table is empty, ht->count could be 0. */
|
|
|
1282 xnew_array (Lisp_Object, 2 * (ht->count > 0 ? ht->count : 1));
|
|
|
1283 const hentry *e, *sentinel;
|
|
|
1284 Lisp_Object *pobj;
|
|
|
1285
|
|
|
1286 for (e = ht->hentries, sentinel = e + ht->size, pobj = objs; e < sentinel; e++)
|
|
|
1287 if (!HENTRY_CLEAR_P (e))
|
|
|
1288 {
|
|
|
1289 *(pobj++) = e->key;
|
|
|
1290 *(pobj++) = e->value;
|
|
|
1291 }
|
|
|
1292
|
|
|
1293 type_checking_assert (pobj == objs + 2 * ht->count);
|
|
|
1294
|
|
|
1295 return objs;
|
|
|
1296 }
|
|
|
1297
|
|
428
|
1298 DEFUN ("maphash", Fmaphash, 2, 2, 0, /*
|
|
|
1299 Map FUNCTION over entries in HASH-TABLE, calling it with two args,
|
|
|
1300 each key and value in HASH-TABLE.
|
|
|
1301
|
|
489
|
1302 FUNCTION must not modify HASH-TABLE, with the one exception that FUNCTION
|
|
428
|
1303 may remhash or puthash the entry currently being processed by FUNCTION.
|
|
|
1304 */
|
|
|
1305 (function, hash_table))
|
|
|
1306 {
|
|
489
|
1307 const Lisp_Hash_Table * const ht = xhash_table (hash_table);
|
|
|
1308 Lisp_Object * const objs = copy_compress_hentries (ht);
|
|
|
1309 Lisp_Object args[3];
|
|
|
1310 const Lisp_Object *pobj, *end;
|
|
|
1311 int speccount = specpdl_depth ();
|
|
|
1312 struct gcpro gcpro1;
|
|
|
1313
|
|
|
1314 record_unwind_protect (maphash_unwind, make_opaque_ptr ((void *)objs));
|
|
|
1315 GCPRO1 (objs[0]);
|
|
|
1316 gcpro1.nvars = 2 * ht->count;
|
|
428
|
1317
|
|
489
|
1318 args[0] = function;
|
|
|
1319
|
|
|
1320 for (pobj = objs, end = pobj + 2 * ht->count; pobj < end; pobj += 2)
|
|
|
1321 {
|
|
|
1322 args[1] = pobj[0];
|
|
|
1323 args[2] = pobj[1];
|
|
|
1324 Ffuncall (countof (args), args);
|
|
|
1325 }
|
|
|
1326
|
|
|
1327 unbind_to (speccount, Qnil);
|
|
|
1328 UNGCPRO;
|
|
428
|
1329
|
|
|
1330 return Qnil;
|
|
|
1331 }
|
|
|
1332
|
|
489
|
1333 /* Map *C* function FUNCTION over the elements of a non-weak lisp hash table.
|
|
|
1334 FUNCTION must not modify HASH-TABLE, with the one exception that FUNCTION
|
|
|
1335 may puthash the entry currently being processed by FUNCTION.
|
|
|
1336 Mapping terminates if FUNCTION returns something other than 0. */
|
|
428
|
1337 void
|
|
489
|
1338 elisp_maphash_unsafe (maphash_function_t function,
|
|
428
|
1339 Lisp_Object hash_table, void *extra_arg)
|
|
|
1340 {
|
|
442
|
1341 const Lisp_Hash_Table *ht = XHASH_TABLE (hash_table);
|
|
|
1342 const hentry *e, *sentinel;
|
|
428
|
1343
|
|
|
1344 for (e = ht->hentries, sentinel = e + ht->size; e < sentinel; e++)
|
|
|
1345 if (!HENTRY_CLEAR_P (e))
|
|
489
|
1346 if (function (e->key, e->value, extra_arg))
|
|
|
1347 return;
|
|
428
|
1348 }
|
|
|
1349
|
|
489
|
1350 /* Map *C* function FUNCTION over the elements of a lisp hash table.
|
|
|
1351 It is safe for FUNCTION to modify HASH-TABLE.
|
|
|
1352 Mapping terminates if FUNCTION returns something other than 0. */
|
|
|
1353 void
|
|
|
1354 elisp_maphash (maphash_function_t function,
|
|
|
1355 Lisp_Object hash_table, void *extra_arg)
|
|
|
1356 {
|
|
|
1357 const Lisp_Hash_Table * const ht = xhash_table (hash_table);
|
|
|
1358 Lisp_Object * const objs = copy_compress_hentries (ht);
|
|
|
1359 const Lisp_Object *pobj, *end;
|
|
|
1360 int speccount = specpdl_depth ();
|
|
|
1361 struct gcpro gcpro1;
|
|
|
1362
|
|
|
1363 record_unwind_protect (maphash_unwind, make_opaque_ptr ((void *)objs));
|
|
|
1364 GCPRO1 (objs[0]);
|
|
|
1365 gcpro1.nvars = 2 * ht->count;
|
|
|
1366
|
|
|
1367 for (pobj = objs, end = pobj + 2 * ht->count; pobj < end; pobj += 2)
|
|
|
1368 if (function (pobj[0], pobj[1], extra_arg))
|
|
|
1369 break;
|
|
|
1370
|
|
|
1371 unbind_to (speccount, Qnil);
|
|
|
1372 UNGCPRO;
|
|
|
1373 }
|
|
|
1374
|
|
|
1375 /* Remove all elements of a lisp hash table satisfying *C* predicate PREDICATE.
|
|
|
1376 PREDICATE must not modify HASH-TABLE. */
|
|
428
|
1377 void
|
|
|
1378 elisp_map_remhash (maphash_function_t predicate,
|
|
|
1379 Lisp_Object hash_table, void *extra_arg)
|
|
|
1380 {
|
|
489
|
1381 const Lisp_Hash_Table * const ht = xhash_table (hash_table);
|
|
|
1382 Lisp_Object * const objs = copy_compress_hentries (ht);
|
|
|
1383 const Lisp_Object *pobj, *end;
|
|
|
1384 int speccount = specpdl_depth ();
|
|
|
1385 struct gcpro gcpro1;
|
|
428
|
1386
|
|
489
|
1387 record_unwind_protect (maphash_unwind, make_opaque_ptr ((void *)objs));
|
|
|
1388 GCPRO1 (objs[0]);
|
|
|
1389 gcpro1.nvars = 2 * ht->count;
|
|
|
1390
|
|
|
1391 for (pobj = objs, end = pobj + 2 * ht->count; pobj < end; pobj += 2)
|
|
|
1392 if (predicate (pobj[0], pobj[1], extra_arg))
|
|
|
1393 Fremhash (pobj[0], hash_table);
|
|
|
1394
|
|
|
1395 unbind_to (speccount, Qnil);
|
|
|
1396 UNGCPRO;
|
|
428
|
1397 }
|
|
|
1398
|
|
|
1399
|
|
|
1400 /************************************************************************/
|
|
|
1401 /* garbage collecting weak hash tables */
|
|
|
1402 /************************************************************************/
|
|
442
|
1403 #define MARK_OBJ(obj) do { \
|
|
|
1404 Lisp_Object mo_obj = (obj); \
|
|
|
1405 if (!marked_p (mo_obj)) \
|
|
|
1406 { \
|
|
|
1407 mark_object (mo_obj); \
|
|
|
1408 did_mark = 1; \
|
|
|
1409 } \
|
|
|
1410 } while (0)
|
|
|
1411
|
|
428
|
1412
|
|
|
1413 /* Complete the marking for semi-weak hash tables. */
|
|
|
1414 int
|
|
|
1415 finish_marking_weak_hash_tables (void)
|
|
|
1416 {
|
|
|
1417 Lisp_Object hash_table;
|
|
|
1418 int did_mark = 0;
|
|
|
1419
|
|
|
1420 for (hash_table = Vall_weak_hash_tables;
|
|
|
1421 !NILP (hash_table);
|
|
|
1422 hash_table = XHASH_TABLE (hash_table)->next_weak)
|
|
|
1423 {
|
|
442
|
1424 const Lisp_Hash_Table *ht = XHASH_TABLE (hash_table);
|
|
|
1425 const hentry *e = ht->hentries;
|
|
|
1426 const hentry *sentinel = e + ht->size;
|
|
428
|
1427
|
|
|
1428 if (! marked_p (hash_table))
|
|
|
1429 /* The hash table is probably garbage. Ignore it. */
|
|
|
1430 continue;
|
|
|
1431
|
|
|
1432 /* Now, scan over all the pairs. For all pairs that are
|
|
|
1433 half-marked, we may need to mark the other half if we're
|
|
|
1434 keeping this pair. */
|
|
|
1435 switch (ht->weakness)
|
|
|
1436 {
|
|
|
1437 case HASH_TABLE_KEY_WEAK:
|
|
|
1438 for (; e < sentinel; e++)
|
|
|
1439 if (!HENTRY_CLEAR_P (e))
|
|
|
1440 if (marked_p (e->key))
|
|
|
1441 MARK_OBJ (e->value);
|
|
|
1442 break;
|
|
|
1443
|
|
|
1444 case HASH_TABLE_VALUE_WEAK:
|
|
|
1445 for (; e < sentinel; e++)
|
|
|
1446 if (!HENTRY_CLEAR_P (e))
|
|
|
1447 if (marked_p (e->value))
|
|
|
1448 MARK_OBJ (e->key);
|
|
|
1449 break;
|
|
|
1450
|
|
442
|
1451 case HASH_TABLE_KEY_VALUE_WEAK:
|
|
|
1452 for (; e < sentinel; e++)
|
|
|
1453 if (!HENTRY_CLEAR_P (e))
|
|
|
1454 {
|
|
|
1455 if (marked_p (e->value))
|
|
|
1456 MARK_OBJ (e->key);
|
|
|
1457 else if (marked_p (e->key))
|
|
|
1458 MARK_OBJ (e->value);
|
|
|
1459 }
|
|
|
1460 break;
|
|
|
1461
|
|
428
|
1462 case HASH_TABLE_KEY_CAR_WEAK:
|
|
|
1463 for (; e < sentinel; e++)
|
|
|
1464 if (!HENTRY_CLEAR_P (e))
|
|
|
1465 if (!CONSP (e->key) || marked_p (XCAR (e->key)))
|
|
|
1466 {
|
|
|
1467 MARK_OBJ (e->key);
|
|
|
1468 MARK_OBJ (e->value);
|
|
|
1469 }
|
|
|
1470 break;
|
|
|
1471
|
|
450
|
1472 /* We seem to be sprouting new weakness types at an alarming
|
|
|
1473 rate. At least this is not externally visible - and in
|
|
|
1474 fact all of these KEY_CAR_* types are only used by the
|
|
|
1475 glyph code. */
|
|
|
1476 case HASH_TABLE_KEY_CAR_VALUE_WEAK:
|
|
|
1477 for (; e < sentinel; e++)
|
|
|
1478 if (!HENTRY_CLEAR_P (e))
|
|
|
1479 {
|
|
|
1480 if (!CONSP (e->key) || marked_p (XCAR (e->key)))
|
|
|
1481 {
|
|
|
1482 MARK_OBJ (e->key);
|
|
|
1483 MARK_OBJ (e->value);
|
|
|
1484 }
|
|
|
1485 else if (marked_p (e->value))
|
|
|
1486 MARK_OBJ (e->key);
|
|
|
1487 }
|
|
|
1488 break;
|
|
|
1489
|
|
428
|
1490 case HASH_TABLE_VALUE_CAR_WEAK:
|
|
|
1491 for (; e < sentinel; e++)
|
|
|
1492 if (!HENTRY_CLEAR_P (e))
|
|
|
1493 if (!CONSP (e->value) || marked_p (XCAR (e->value)))
|
|
|
1494 {
|
|
|
1495 MARK_OBJ (e->key);
|
|
|
1496 MARK_OBJ (e->value);
|
|
|
1497 }
|
|
|
1498 break;
|
|
|
1499
|
|
|
1500 default:
|
|
|
1501 break;
|
|
|
1502 }
|
|
|
1503 }
|
|
|
1504
|
|
|
1505 return did_mark;
|
|
|
1506 }
|
|
|
1507
|
|
|
1508 void
|
|
|
1509 prune_weak_hash_tables (void)
|
|
|
1510 {
|
|
|
1511 Lisp_Object hash_table, prev = Qnil;
|
|
|
1512 for (hash_table = Vall_weak_hash_tables;
|
|
|
1513 !NILP (hash_table);
|
|
|
1514 hash_table = XHASH_TABLE (hash_table)->next_weak)
|
|
|
1515 {
|
|
|
1516 if (! marked_p (hash_table))
|
|
|
1517 {
|
|
|
1518 /* This hash table itself is garbage. Remove it from the list. */
|
|
|
1519 if (NILP (prev))
|
|
|
1520 Vall_weak_hash_tables = XHASH_TABLE (hash_table)->next_weak;
|
|
|
1521 else
|
|
|
1522 XHASH_TABLE (prev)->next_weak = XHASH_TABLE (hash_table)->next_weak;
|
|
|
1523 }
|
|
|
1524 else
|
|
|
1525 {
|
|
|
1526 /* Now, scan over all the pairs. Remove all of the pairs
|
|
|
1527 in which the key or value, or both, is unmarked
|
|
|
1528 (depending on the weakness of the hash table). */
|
|
|
1529 Lisp_Hash_Table *ht = XHASH_TABLE (hash_table);
|
|
|
1530 hentry *entries = ht->hentries;
|
|
|
1531 hentry *sentinel = entries + ht->size;
|
|
|
1532 hentry *e;
|
|
|
1533
|
|
|
1534 for (e = entries; e < sentinel; e++)
|
|
|
1535 if (!HENTRY_CLEAR_P (e))
|
|
|
1536 {
|
|
|
1537 again:
|
|
|
1538 if (!marked_p (e->key) || !marked_p (e->value))
|
|
|
1539 {
|
|
|
1540 remhash_1 (ht, entries, e);
|
|
|
1541 if (!HENTRY_CLEAR_P (e))
|
|
|
1542 goto again;
|
|
|
1543 }
|
|
|
1544 }
|
|
|
1545
|
|
|
1546 prev = hash_table;
|
|
|
1547 }
|
|
|
1548 }
|
|
|
1549 }
|
|
|
1550
|
|
|
1551 /* Return a hash value for an array of Lisp_Objects of size SIZE. */
|
|
|
1552
|
|
647
|
1553 Hash_Code
|
|
428
|
1554 internal_array_hash (Lisp_Object *arr, int size, int depth)
|
|
|
1555 {
|
|
|
1556 int i;
|
|
647
|
1557 Hash_Code hash = 0;
|
|
442
|
1558 depth++;
|
|
428
|
1559
|
|
|
1560 if (size <= 5)
|
|
|
1561 {
|
|
|
1562 for (i = 0; i < size; i++)
|
|
442
|
1563 hash = HASH2 (hash, internal_hash (arr[i], depth));
|
|
428
|
1564 return hash;
|
|
|
1565 }
|
|
|
1566
|
|
|
1567 /* just pick five elements scattered throughout the array.
|
|
|
1568 A slightly better approach would be to offset by some
|
|
|
1569 noise factor from the points chosen below. */
|
|
|
1570 for (i = 0; i < 5; i++)
|
|
442
|
1571 hash = HASH2 (hash, internal_hash (arr[i*size/5], depth));
|
|
428
|
1572
|
|
|
1573 return hash;
|
|
|
1574 }
|
|
|
1575
|
|
|
1576 /* Return a hash value for a Lisp_Object. This is for use when hashing
|
|
|
1577 objects with the comparison being `equal' (for `eq', you can just
|
|
|
1578 use the Lisp_Object itself as the hash value). You need to make a
|
|
|
1579 tradeoff between the speed of the hash function and how good the
|
|
|
1580 hashing is. In particular, the hash function needs to be FAST,
|
|
|
1581 so you can't just traipse down the whole tree hashing everything
|
|
|
1582 together. Most of the time, objects will differ in the first
|
|
|
1583 few elements you hash. Thus, we only go to a short depth (5)
|
|
|
1584 and only hash at most 5 elements out of a vector. Theoretically
|
|
|
1585 we could still take 5^5 time (a big big number) to compute a
|
|
|
1586 hash, but practically this won't ever happen. */
|
|
|
1587
|
|
647
|
1588 Hash_Code
|
|
428
|
1589 internal_hash (Lisp_Object obj, int depth)
|
|
|
1590 {
|
|
|
1591 if (depth > 5)
|
|
|
1592 return 0;
|
|
|
1593 if (CONSP (obj))
|
|
|
1594 {
|
|
|
1595 /* no point in worrying about tail recursion, since we're not
|
|
|
1596 going very deep */
|
|
|
1597 return HASH2 (internal_hash (XCAR (obj), depth + 1),
|
|
|
1598 internal_hash (XCDR (obj), depth + 1));
|
|
|
1599 }
|
|
|
1600 if (STRINGP (obj))
|
|
|
1601 {
|
|
|
1602 return hash_string (XSTRING_DATA (obj), XSTRING_LENGTH (obj));
|
|
|
1603 }
|
|
|
1604 if (LRECORDP (obj))
|
|
|
1605 {
|
|
442
|
1606 const struct lrecord_implementation
|
|
428
|
1607 *imp = XRECORD_LHEADER_IMPLEMENTATION (obj);
|
|
|
1608 if (imp->hash)
|
|
|
1609 return imp->hash (obj, depth);
|
|
|
1610 }
|
|
|
1611
|
|
|
1612 return LISP_HASH (obj);
|
|
|
1613 }
|
|
|
1614
|
|
|
1615 DEFUN ("sxhash", Fsxhash, 1, 1, 0, /*
|
|
|
1616 Return a hash value for OBJECT.
|
|
444
|
1617 \(equal obj1 obj2) implies (= (sxhash obj1) (sxhash obj2)).
|
|
428
|
1618 */
|
|
|
1619 (object))
|
|
|
1620 {
|
|
|
1621 return make_int (internal_hash (object, 0));
|
|
|
1622 }
|
|
|
1623
|
|
|
1624 #if 0
|
|
|
1625 xxDEFUN ("internal-hash-value", Finternal_hash_value, 1, 1, 0, /*
|
|
|
1626 Hash value of OBJECT. For debugging.
|
|
|
1627 The value is returned as (HIGH . LOW).
|
|
|
1628 */
|
|
|
1629 (object))
|
|
|
1630 {
|
|
|
1631 /* This function is pretty 32bit-centric. */
|
|
647
|
1632 Hash_Code hash = internal_hash (object, 0);
|
|
428
|
1633 return Fcons (hash >> 16, hash & 0xffff);
|
|
|
1634 }
|
|
|
1635 #endif
|
|
|
1636
|
|
|
1637
|
|
|
1638 /************************************************************************/
|
|
|
1639 /* initialization */
|
|
|
1640 /************************************************************************/
|
|
|
1641
|
|
|
1642 void
|
|
|
1643 syms_of_elhash (void)
|
|
|
1644 {
|
|
442
|
1645 INIT_LRECORD_IMPLEMENTATION (hash_table);
|
|
|
1646
|
|
428
|
1647 DEFSUBR (Fhash_table_p);
|
|
|
1648 DEFSUBR (Fmake_hash_table);
|
|
|
1649 DEFSUBR (Fcopy_hash_table);
|
|
|
1650 DEFSUBR (Fgethash);
|
|
|
1651 DEFSUBR (Fremhash);
|
|
|
1652 DEFSUBR (Fputhash);
|
|
|
1653 DEFSUBR (Fclrhash);
|
|
|
1654 DEFSUBR (Fmaphash);
|
|
|
1655 DEFSUBR (Fhash_table_count);
|
|
|
1656 DEFSUBR (Fhash_table_test);
|
|
|
1657 DEFSUBR (Fhash_table_size);
|
|
|
1658 DEFSUBR (Fhash_table_rehash_size);
|
|
|
1659 DEFSUBR (Fhash_table_rehash_threshold);
|
|
|
1660 DEFSUBR (Fhash_table_weakness);
|
|
|
1661 DEFSUBR (Fhash_table_type); /* obsolete */
|
|
|
1662 DEFSUBR (Fsxhash);
|
|
|
1663 #if 0
|
|
|
1664 DEFSUBR (Finternal_hash_value);
|
|
|
1665 #endif
|
|
|
1666
|
|
563
|
1667 DEFSYMBOL_MULTIWORD_PREDICATE (Qhash_tablep);
|
|
|
1668 DEFSYMBOL (Qhash_table);
|
|
|
1669 DEFSYMBOL (Qhashtable);
|
|
|
1670 DEFSYMBOL (Qweakness);
|
|
|
1671 DEFSYMBOL (Qvalue);
|
|
|
1672 DEFSYMBOL (Qkey_or_value);
|
|
|
1673 DEFSYMBOL (Qkey_and_value);
|
|
|
1674 DEFSYMBOL (Qrehash_size);
|
|
|
1675 DEFSYMBOL (Qrehash_threshold);
|
|
428
|
1676
|
|
563
|
1677 DEFSYMBOL (Qweak); /* obsolete */
|
|
|
1678 DEFSYMBOL (Qkey_weak); /* obsolete */
|
|
|
1679 DEFSYMBOL (Qkey_or_value_weak); /* obsolete */
|
|
|
1680 DEFSYMBOL (Qvalue_weak); /* obsolete */
|
|
|
1681 DEFSYMBOL (Qnon_weak); /* obsolete */
|
|
428
|
1682
|
|
563
|
1683 DEFKEYWORD (Q_test);
|
|
|
1684 DEFKEYWORD (Q_size);
|
|
|
1685 DEFKEYWORD (Q_rehash_size);
|
|
|
1686 DEFKEYWORD (Q_rehash_threshold);
|
|
|
1687 DEFKEYWORD (Q_weakness);
|
|
|
1688 DEFKEYWORD (Q_type); /* obsolete */
|
|
428
|
1689 }
|
|
|
1690
|
|
|
1691 void
|
|
|
1692 vars_of_elhash (void)
|
|
|
1693 {
|
|
|
1694 /* This must NOT be staticpro'd */
|
|
|
1695 Vall_weak_hash_tables = Qnil;
|
|
452
|
1696 dump_add_weak_object_chain (&Vall_weak_hash_tables);
|
|
428
|
1697 }
|
