lib/bitset.h

   1 /* Generic bitsets.
   2    Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
   3    Contributed by Michael Hayes (m.hayes@elec.canterbury.ac.nz).
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  18
  19 #ifndef _BITSET_H
  20 #define _BITSET_H
  21
  22 /* This file is the public interface to the bitset abstract data type.
  23    Only use the functions and macros defined in this file.  */
  24
  25 #include "bbitset.h"
  26 #include "obstack.h"
  27 #include <stdio.h>
  28
  29 #if USE_UNLOCKED_IO
  30 # include "unlocked-io.h"
  31 #endif
  32
  33 /* Attributes used to select a bitset implementation.  */
  34 enum bitset_attr {BITSET_FIXED = 1,    /* Bitset size fixed.  */
  35                   BITSET_VARIABLE = 2, /* Bitset size variable.  */
  36                   BITSET_DENSE = 4,    /* Bitset dense.  */
  37                   BITSET_SPARSE = 8,   /* Bitset sparse.  */
  38                   BITSET_FRUGAL = 16,  /* Prefer most compact.  */
  39                   BITSET_GREEDY = 32}; /* Prefer fastest at memory expense.  */
  40
  41 typedef unsigned int bitset_attrs;
  42
  43 /* The contents of the union should be considered to be private.
  44    While I would like to make this union opaque, it needs to be
  45    visible for the inline bit set/test functions, and for delegation
  46    to the proper implementation.  */
  47 union bitset_union
  48 {
  49   /* This must be the first member of every other structure that is a
  50      member of this union.  */
  51   struct bbitset_struct b;              /* Base bitset data.  */
  52
  53   struct abitset_struct
  54   {
  55     struct bbitset_struct b;
  56     bitset_word words[1];               /* The array of bits.  */
  57   } a;
  58
  59   struct ebitset_struct
  60   {
  61     struct bbitset_struct b;
  62     bitset_windex size;                 /* Number of elements.  */
  63     struct ebitset_elt_struct **elts;   /* Expanding array of ptrs to elts.  */
  64   } e;
  65
  66   struct lbitset_struct
  67   {
  68     struct bbitset_struct b;
  69     struct lbitset_elt_struct *head;    /* First element in linked list.  */
  70     struct lbitset_elt_struct *tail;    /* Last element in linked list.  */
  71   } l;
  72
  73   struct bitset_stats_struct
  74   {
  75     struct bbitset_struct b;
  76     bitset bset;
  77   } s;
  78
  79   struct vbitset_struct
  80   {
  81     struct bbitset_struct b;
  82     bitset_windex size;                 /* Allocated size of array.  */
  83   } v;
  84
  85 };
  86
  87
  88 /* The contents of this structure should be considered private.
  89    It is used for iterating over set bits.  */
  90 typedef struct
  91 {
  92   bitset_bindex list[BITSET_LIST_SIZE];
  93   bitset_bindex next;
  94   bitset_bindex num;
  95   bitset_bindex i;
  96 } bitset_iterator;
  97
  98
  99 /* Return bytes required for bitset of desired type and size.  */
 100 extern size_t bitset_bytes (enum bitset_type, bitset_bindex);
 101
 102 /* Initialise a bitset with desired type and size.  */
 103 extern bitset bitset_init (bitset, bitset_bindex, enum bitset_type);
 104
 105 /* Select an implementation type based on the desired bitset size
 106    and attributes.  */
 107 extern enum bitset_type bitset_type_choose (bitset_bindex, bitset_attrs);
 108
 109 /* Create a bitset of desired type and size.  The bitset is zeroed.  */
 110 extern bitset bitset_alloc (bitset_bindex, enum bitset_type);
 111
 112 /* Free bitset.  */
 113 extern void bitset_free (bitset);
 114
 115 /* Create a bitset of desired type and size using an obstack.  The
 116    bitset is zeroed.  */
 117 extern bitset bitset_obstack_alloc (struct obstack *bobstack,
 118                                     bitset_bindex, enum bitset_type);
 119
 120 /* Free bitset allocated on obstack.  */
 121 extern void bitset_obstack_free (bitset);
 122
 123 /* Create a bitset of desired size and attributes.  The bitset is zeroed.  */
 124 extern bitset bitset_create (bitset_bindex, bitset_attrs);
 125
 126 /* Return bitset type.  */
 127 extern enum bitset_type bitset_type_get (bitset);
 128
 129 /* Return bitset type name.  */
 130 extern const char *bitset_type_name_get (bitset);
 131
 132
 133 /* Set bit BITNO in bitset BSET.  */
 134 static inline void
 135 bitset_set (bitset bset, bitset_bindex bitno)
 136 {
 137   bitset_windex windex = bitno / BITSET_WORD_BITS;
 138   bitset_windex offset = windex - bset->b.cindex;
 139
 140   if (offset < bset->b.csize)
 141     bset->b.cdata[offset] |= ((bitset_word) 1 << (bitno % BITSET_WORD_BITS));
 142   else
 143     BITSET_SET_ (bset, bitno);
 144 }
 145
 146
 147 /* Reset bit BITNO in bitset BSET.  */
 148 static inline void
 149 bitset_reset (bitset bset, bitset_bindex bitno)
 150 {
 151   bitset_windex windex = bitno / BITSET_WORD_BITS;
 152   bitset_windex offset = windex - bset->b.cindex;
 153
 154   if (offset < bset->b.csize)
 155     bset->b.cdata[offset] &= ~((bitset_word) 1 << (bitno % BITSET_WORD_BITS));
 156   else
 157     BITSET_RESET_ (bset, bitno);
 158 }
 159
 160
 161 /* Test bit BITNO in bitset BSET.  */
 162 static inline bool
 163 bitset_test (bitset bset, bitset_bindex bitno)
 164 {
 165   bitset_windex windex = bitno / BITSET_WORD_BITS;
 166   bitset_windex offset = windex - bset->b.cindex;
 167
 168   if (offset < bset->b.csize)
 169     return (bset->b.cdata[offset] >> (bitno % BITSET_WORD_BITS)) & 1;
 170   else
 171     return BITSET_TEST_ (bset, bitno);
 172 }
 173
 174
 175 /* Toggle bit BITNO in bitset BSET and return non-zero if now set.  */
 176 #define bitset_toggle(bset, bitno) BITSET_TOGGLE_ (bset, bitno)
 177
 178 /* Return size in bits of bitset SRC.  */
 179 #define bitset_size(SRC) BITSET_SIZE_ (SRC)
 180
 181 /* Change size of bitset.  */
 182 extern void bitset_resize (bitset, bitset_bindex);
 183
 184 /* Return number of bits set in bitset SRC.  */
 185 #define bitset_count(SRC) BITSET_COUNT_ (SRC)
 186
 187
 188 /* Return SRC == 0.  */
 189 #define bitset_empty_p(SRC) BITSET_EMPTY_P_ (SRC)
 190
 191 /* DST = ~0.  */
 192 #define bitset_ones(DST) BITSET_ONES_ (DST)
 193
 194 /* DST = 0.  */
 195 #define bitset_zero(DST) BITSET_ZERO_ (DST)
 196
 197
 198
 199 /* DST = SRC.  */
 200 #define bitset_copy(DST, SRC) BITSET_COPY_ (DST, SRC)
 201
 202 /* Return DST & SRC == 0.  */
 203 #define bitset_disjoint_p(DST, SRC) BITSET_DISJOINT_P_ (DST, SRC)
 204
 205 /* Return DST == SRC.  */
 206 #define bitset_equal_p(DST, SRC) BITSET_EQUAL_P_ (DST, SRC)
 207
 208 /* DST = ~SRC.  */
 209 #define bitset_not(DST, SRC) BITSET_NOT_ (DST, SRC)
 210
 211 /* Return DST == DST | SRC.  */
 212 #define bitset_subset_p(DST, SRC) BITSET_SUBSET_P_ (DST, SRC)
 213
 214
 215
 216 /* DST = SRC1 & SRC2.  */
 217 #define bitset_and(DST, SRC1, SRC2) BITSET_AND_ (DST, SRC1, SRC2)
 218
 219 /* DST = SRC1 & SRC2.  Return non-zero if DST != SRC1 & SRC2.  */
 220 #define bitset_and_cmp(DST, SRC1, SRC2) BITSET_AND_CMP_ (DST, SRC1, SRC2)
 221
 222 /* DST = SRC1 & ~SRC2.  */
 223 #define bitset_andn(DST, SRC1, SRC2) BITSET_ANDN_ (DST, SRC1, SRC2)
 224
 225 /* DST = SRC1 & ~SRC2.  Return non-zero if DST != SRC1 & ~SRC2.  */
 226 #define bitset_andn_cmp(DST, SRC1, SRC2) BITSET_ANDN_CMP_ (DST, SRC1, SRC2)
 227
 228 /* DST = SRC1 | SRC2.  */
 229 #define bitset_or(DST, SRC1, SRC2) BITSET_OR_ (DST, SRC1, SRC2)
 230
 231 /* DST = SRC1 | SRC2.  Return non-zero if DST != SRC1 | SRC2.  */
 232 #define bitset_or_cmp(DST, SRC1, SRC2) BITSET_OR_CMP_ (DST, SRC1, SRC2)
 233
 234 /* DST = SRC1 ^ SRC2.  */
 235 #define bitset_xor(DST, SRC1, SRC2) BITSET_XOR_ (DST, SRC1, SRC2)
 236
 237 /* DST = SRC1 ^ SRC2.  Return non-zero if DST != SRC1 ^ SRC2.  */
 238 #define bitset_xor_cmp(DST, SRC1, SRC2) BITSET_XOR_CMP_ (DST, SRC1, SRC2)
 239
 240
 241
 242 /* DST = (SRC1 & SRC2) | SRC3.  */
 243 #define bitset_and_or(DST, SRC1, SRC2, SRC3) \
 244  BITSET_AND_OR_ (DST, SRC1, SRC2, SRC3)
 245
 246 /* DST = (SRC1 & SRC2) | SRC3.  Return non-zero if
 247    DST != (SRC1 & SRC2) | SRC3.  */
 248 #define bitset_and_or_cmp(DST, SRC1, SRC2, SRC3) \
 249  BITSET_AND_OR_CMP_ (DST, SRC1, SRC2, SRC3)
 250
 251 /* DST = (SRC1 & ~SRC2) | SRC3.  */
 252 #define bitset_andn_or(DST, SRC1, SRC2, SRC3) \
 253  BITSET_ANDN_OR_ (DST, SRC1, SRC2, SRC3)
 254
 255 /* DST = (SRC1 & ~SRC2) | SRC3.  Return non-zero if
 256    DST != (SRC1 & ~SRC2) | SRC3.  */
 257 #define bitset_andn_or_cmp(DST, SRC1, SRC2, SRC3) \
 258  BITSET_ANDN_OR_CMP_ (DST, SRC1, SRC2, SRC3)
 259
 260 /* DST = (SRC1 | SRC2) & SRC3.  */
 261 #define bitset_or_and(DST, SRC1, SRC2, SRC3)\
 262  BITSET_OR_AND_ (DST, SRC1, SRC2, SRC3)
 263
 264 /* DST = (SRC1 | SRC2) & SRC3.  Return non-zero if
 265    DST != (SRC1 | SRC2) & SRC3.  */
 266 #define bitset_or_and_cmp(DST, SRC1, SRC2, SRC3)\
 267  BITSET_OR_AND_CMP_ (DST, SRC1, SRC2, SRC3)
 268
 269 /* Find list of up to NUM bits set in BSET starting from and including
 270    *NEXT.  Return with actual number of bits found and with *NEXT
 271    indicating where search stopped.  */
 272 #define bitset_list(BSET, LIST, NUM, NEXT) \
 273  BITSET_LIST_ (BSET, LIST, NUM, NEXT)
 274
 275 /* Find reverse list of up to NUM bits set in BSET starting from and
 276    including NEXT.  Return with actual number of bits found and with
 277    *NEXT indicating where search stopped.  */
 278 #define bitset_list_reverse(BSET, LIST, NUM, NEXT) \
 279  BITSET_LIST_REVERSE_ (BSET, LIST, NUM, NEXT)
 280
 281 /* Return true if both bitsets are of the same type and size.  */
 282 extern bool bitset_compatible_p (bitset bset1, bitset bset2);
 283
 284 /* Find next set bit from the given bit index.  */
 285 extern bitset_bindex bitset_next (bitset, bitset_bindex);
 286
 287 /* Find previous set bit from the given bit index.  */
 288 extern bitset_bindex bitset_prev (bitset, bitset_bindex);
 289
 290 /* Find first set bit.  */
 291 extern bitset_bindex bitset_first (bitset);
 292
 293 /* Find last set bit.  */
 294 extern bitset_bindex bitset_last (bitset);
 295
 296 /* Return nonzero if this is the only set bit.  */
 297 extern bool bitset_only_set_p (bitset, bitset_bindex);
 298
 299 /* Dump bitset.  */
 300 extern void bitset_dump (FILE *, bitset);
 301
 302 /* Loop over all elements of BSET, starting with MIN, setting INDEX
 303    to the index of each set bit.  For example, the following will print
 304    the bits set in a bitset:
 305
 306    bitset_bindex i;
 307    bitset_iterator iter;
 308
 309    BITSET_FOR_EACH (iter, src, i, 0)
 310    {
 311       printf ("%lu ", (unsigned long int) i);
 312    };
 313 */
 314 #define BITSET_FOR_EACH(ITER, BSET, INDEX, MIN)                               \
 315   for (ITER.next = (MIN), ITER.num = BITSET_LIST_SIZE;                        \
 316        (ITER.num == BITSET_LIST_SIZE)                                         \
 317        && (ITER.num = bitset_list (BSET, ITER.list,                           \
 318                                    BITSET_LIST_SIZE, &ITER.next));)           \
 319     for (ITER.i = 0;                                                          \
 320          ITER.i < ITER.num && ((INDEX) = ITER.list[ITER.i], 1);               \
 321          ITER.i++)
 322
 323
 324 /* Loop over all elements of BSET, in reverse order starting with
 325    MIN, setting INDEX to the index of each set bit.  For example, the
 326    following will print the bits set in a bitset in reverse order:
 327
 328    bitset_bindex i;
 329    bitset_iterator iter;
 330
 331    BITSET_FOR_EACH_REVERSE (iter, src, i, 0)
 332    {
 333       printf ("%lu ", (unsigned long int) i);
 334    };
 335 */
 336 #define BITSET_FOR_EACH_REVERSE(ITER, BSET, INDEX, MIN)                       \
 337   for (ITER.next = (MIN), ITER.num = BITSET_LIST_SIZE;                        \
 338        (ITER.num == BITSET_LIST_SIZE)                                         \
 339        && (ITER.num = bitset_list_reverse (BSET, ITER.list,                   \
 340                                            BITSET_LIST_SIZE, &ITER.next));)   \
 341     for (ITER.i = 0;                                                          \
 342          ITER.i < ITER.num && ((INDEX) = ITER.list[ITER.i], 1);               \
 343          ITER.i++)
 344
 345
 346 /* Define set operations in terms of logical operations.  */
 347
 348 #define bitset_diff(DST, SRC1, SRC2) bitset_andn (DST, SRC1, SRC2)
 349 #define bitset_diff_cmp(DST, SRC1, SRC2) bitset_andn_cmp (DST, SRC1, SRC2)
 350
 351 #define bitset_intersection(DST, SRC1, SRC2) bitset_and (DST, SRC1, SRC2)
 352 #define bitset_intersection_cmp(DST, SRC1, SRC2) bitset_and_cmp (DST, SRC1, SRC2)
 353
 354 #define bitset_union(DST, SRC1, SRC2) bitset_or (DST, SRC1, SRC2)
 355 #define bitset_union_cmp(DST, SRC1, SRC2) bitset_or_cmp (DST, SRC1, SRC2)
 356
 357 /* Symmetrical difference.  */
 358 #define bitset_symdiff(DST, SRC1, SRC2) bitset_xor (DST, SRC1, SRC2)
 359 #define bitset_symdiff_cmp(DST, SRC1, SRC2) bitset_xor_cmp (DST, SRC1, SRC2)
 360
 361 /* Union of difference.  */
 362 #define bitset_diff_union(DST, SRC1, SRC2, SRC3) \
 363   bitset_andn_or (DST, SRC1, SRC2, SRC3)
 364 #define bitset_diff_union_cmp(DST, SRC1, SRC2, SRC3) \
 365   bitset_andn_or_cmp (DST, SRC1, SRC2, SRC3)
 366
 367
 368 /* Release any memory tied up with bitsets.  */
 369 extern void bitset_release_memory (void);
 370
 371 /* Enable bitset stats gathering.  */
 372 extern void bitset_stats_enable (void);
 373
 374 /* Disable bitset stats gathering.  */
 375 extern void bitset_stats_disable (void);
 376
 377 /* Read bitset stats file of accummulated stats.  */
 378 void bitset_stats_read (const char *file_name);
 379
 380 /* Write bitset stats file of accummulated stats.  */
 381 void bitset_stats_write (const char *file_name);
 382
 383 /* Dump bitset stats.  */
 384 extern void bitset_stats_dump (FILE *);
 385
 386 /* Function to debug bitset from debugger.  */
 387 extern void debug_bitset (bitset);
 388
 389 /* Function to debug bitset stats from debugger.  */
 390 extern void debug_bitset_stats (void);
 391
 392 #endif /* _BITSET_H  */