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      1 /* Generic bitsets.
      2 
      3    Copyright (C) 2002-2004, 2009-2012 Free Software Foundation, Inc.
      4 
      5    Contributed by Michael Hayes (m.hayes (at) elec.canterbury.ac.nz).
      6 
      7    This program is free software: you can redistribute it and/or modify
      8    it under the terms of the GNU General Public License as published by
      9    the Free Software Foundation, either version 3 of the License, or
     10    (at your option) any later version.
     11 
     12    This program is distributed in the hope that it will be useful,
     13    but WITHOUT ANY WARRANTY; without even the implied warranty of
     14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     15    GNU General Public License for more details.
     16 
     17    You should have received a copy of the GNU General Public License
     18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
     19 
     20 #ifndef _BITSET_H
     21 #define _BITSET_H
     22 
     23 /* This file is the public interface to the bitset abstract data type.
     24    Only use the functions and macros defined in this file.  */
     25 
     26 #include "bbitset.h"
     27 #include "obstack.h"
     28 #include <stdio.h>
     29 
     30 #if USE_UNLOCKED_IO
     31 # include "unlocked-io.h"
     32 #endif
     33 
     34 /* Attributes used to select a bitset implementation.  */
     35 enum bitset_attr {BITSET_FIXED = 1,    /* Bitset size fixed.  */
     36 		  BITSET_VARIABLE = 2, /* Bitset size variable.  */
     37 		  BITSET_DENSE = 4,    /* Bitset dense.  */
     38 		  BITSET_SPARSE = 8,   /* Bitset sparse.  */
     39 		  BITSET_FRUGAL = 16,  /* Prefer most compact.  */
     40 		  BITSET_GREEDY = 32}; /* Prefer fastest at memory expense.  */
     41 
     42 typedef unsigned int bitset_attrs;
     43 
     44 /* The contents of the union should be considered to be private.
     45    While I would like to make this union opaque, it needs to be
     46    visible for the inline bit set/test functions, and for delegation
     47    to the proper implementation.  */
     48 union bitset_union
     49 {
     50   /* This must be the first member of every other structure that is a
     51      member of this union.  */
     52   struct bbitset_struct b;	        /* Base bitset data.  */
     53 
     54   struct abitset_struct
     55   {
     56     struct bbitset_struct b;
     57     bitset_word words[1];		/* The array of bits.  */
     58   } a;
     59 
     60   struct ebitset_struct
     61   {
     62     struct bbitset_struct b;
     63     bitset_windex size;			/* Number of elements.  */
     64     struct ebitset_elt_struct **elts;	/* Expanding array of ptrs to elts.  */
     65   } e;
     66 
     67   struct lbitset_struct
     68   {
     69     struct bbitset_struct b;
     70     struct lbitset_elt_struct *head;	/* First element in linked list.  */
     71     struct lbitset_elt_struct *tail;	/* Last element in linked list.  */
     72   } l;
     73 
     74   struct bitset_stats_struct
     75   {
     76     struct bbitset_struct b;
     77     bitset bset;
     78   } s;
     79 
     80   struct vbitset_struct
     81   {
     82     struct bbitset_struct b;
     83     bitset_windex size;			/* Allocated size of array.  */
     84   } v;
     85 
     86 };
     87 
     88 
     89 /* The contents of this structure should be considered private.
     90    It is used for iterating over set bits.  */
     91 typedef struct
     92 {
     93   bitset_bindex list[BITSET_LIST_SIZE];
     94   bitset_bindex next;
     95   bitset_bindex num;
     96   bitset_bindex i;
     97 } bitset_iterator;
     98 
     99 
    100 /* Return bytes required for bitset of desired type and size.  */
    101 extern size_t bitset_bytes (enum bitset_type, bitset_bindex);
    102 
    103 /* Initialise a bitset with desired type and size.  */
    104 extern bitset bitset_init (bitset, bitset_bindex, enum bitset_type);
    105 
    106 /* Select an implementation type based on the desired bitset size
    107    and attributes.  */
    108 extern enum bitset_type bitset_type_choose (bitset_bindex, bitset_attrs);
    109 
    110 /* Create a bitset of desired type and size.  The bitset is zeroed.  */
    111 extern bitset bitset_alloc (bitset_bindex, enum bitset_type);
    112 
    113 /* Free bitset.  */
    114 extern void bitset_free (bitset);
    115 
    116 /* Create a bitset of desired type and size using an obstack.  The
    117    bitset is zeroed.  */
    118 extern bitset bitset_obstack_alloc (struct obstack *bobstack,
    119 				    bitset_bindex, enum bitset_type);
    120 
    121 /* Free bitset allocated on obstack.  */
    122 extern void bitset_obstack_free (bitset);
    123 
    124 /* Create a bitset of desired size and attributes.  The bitset is zeroed.  */
    125 extern bitset bitset_create (bitset_bindex, bitset_attrs);
    126 
    127 /* Return bitset type.  */
    128 extern enum bitset_type bitset_type_get (bitset);
    129 
    130 /* Return bitset type name.  */
    131 extern const char *bitset_type_name_get (bitset);
    132 
    133 
    134 /* Set bit BITNO in bitset BSET.  */
    135 static inline void
    136 bitset_set (bitset bset, bitset_bindex bitno)
    137 {
    138   bitset_windex windex = bitno / BITSET_WORD_BITS;
    139   bitset_windex offset = windex - bset->b.cindex;
    140 
    141   if (offset < bset->b.csize)
    142     bset->b.cdata[offset] |= ((bitset_word) 1 << (bitno % BITSET_WORD_BITS));
    143   else
    144     BITSET_SET_ (bset, bitno);
    145 }
    146 
    147 
    148 /* Reset bit BITNO in bitset BSET.  */
    149 static inline void
    150 bitset_reset (bitset bset, bitset_bindex bitno)
    151 {
    152   bitset_windex windex = bitno / BITSET_WORD_BITS;
    153   bitset_windex offset = windex - bset->b.cindex;
    154 
    155   if (offset < bset->b.csize)
    156     bset->b.cdata[offset] &= ~((bitset_word) 1 << (bitno % BITSET_WORD_BITS));
    157   else
    158     BITSET_RESET_ (bset, bitno);
    159 }
    160 
    161 
    162 /* Test bit BITNO in bitset BSET.  */
    163 static inline bool
    164 bitset_test (bitset bset, bitset_bindex bitno)
    165 {
    166   bitset_windex windex = bitno / BITSET_WORD_BITS;
    167   bitset_windex offset = windex - bset->b.cindex;
    168 
    169   if (offset < bset->b.csize)
    170     return (bset->b.cdata[offset] >> (bitno % BITSET_WORD_BITS)) & 1;
    171   else
    172     return BITSET_TEST_ (bset, bitno);
    173 }
    174 
    175 
    176 /* Toggle bit BITNO in bitset BSET and return non-zero if now set.  */
    177 #define bitset_toggle(bset, bitno) BITSET_TOGGLE_ (bset, bitno)
    178 
    179 /* Return size in bits of bitset SRC.  */
    180 #define bitset_size(SRC) BITSET_SIZE_ (SRC)
    181 
    182 /* Change size of bitset.  */
    183 extern void bitset_resize (bitset, bitset_bindex);
    184 
    185 /* Return number of bits set in bitset SRC.  */
    186 #define bitset_count(SRC) BITSET_COUNT_ (SRC)
    187 
    188 
    189 /* Return SRC == 0.  */
    190 #define bitset_empty_p(SRC) BITSET_EMPTY_P_ (SRC)
    191 
    192 /* DST = ~0.  */
    193 #define bitset_ones(DST) BITSET_ONES_ (DST)
    194 
    195 /* DST = 0.  */
    196 #define bitset_zero(DST) BITSET_ZERO_ (DST)
    197 
    198 
    199 
    200 /* DST = SRC.  */
    201 #define bitset_copy(DST, SRC) BITSET_COPY_ (DST, SRC)
    202 
    203 /* Return DST & SRC == 0.  */
    204 #define bitset_disjoint_p(DST, SRC) BITSET_DISJOINT_P_ (DST, SRC)
    205 
    206 /* Return DST == SRC.  */
    207 #define bitset_equal_p(DST, SRC) BITSET_EQUAL_P_ (DST, SRC)
    208 
    209 /* DST = ~SRC.  */
    210 #define bitset_not(DST, SRC) BITSET_NOT_ (DST, SRC)
    211 
    212 /* Return DST == DST | SRC.  */
    213 #define bitset_subset_p(DST, SRC) BITSET_SUBSET_P_ (DST, SRC)
    214 
    215 
    216 
    217 /* DST = SRC1 & SRC2.  */
    218 #define bitset_and(DST, SRC1, SRC2) BITSET_AND_ (DST, SRC1, SRC2)
    219 
    220 /* DST = SRC1 & SRC2.  Return non-zero if DST != SRC1 & SRC2.  */
    221 #define bitset_and_cmp(DST, SRC1, SRC2) BITSET_AND_CMP_ (DST, SRC1, SRC2)
    222 
    223 /* DST = SRC1 & ~SRC2.  */
    224 #define bitset_andn(DST, SRC1, SRC2) BITSET_ANDN_ (DST, SRC1, SRC2)
    225 
    226 /* DST = SRC1 & ~SRC2.  Return non-zero if DST != SRC1 & ~SRC2.  */
    227 #define bitset_andn_cmp(DST, SRC1, SRC2) BITSET_ANDN_CMP_ (DST, SRC1, SRC2)
    228 
    229 /* DST = SRC1 | SRC2.  */
    230 #define bitset_or(DST, SRC1, SRC2) BITSET_OR_ (DST, SRC1, SRC2)
    231 
    232 /* DST = SRC1 | SRC2.  Return non-zero if DST != SRC1 | SRC2.  */
    233 #define bitset_or_cmp(DST, SRC1, SRC2) BITSET_OR_CMP_ (DST, SRC1, SRC2)
    234 
    235 /* DST = SRC1 ^ SRC2.  */
    236 #define bitset_xor(DST, SRC1, SRC2) BITSET_XOR_ (DST, SRC1, SRC2)
    237 
    238 /* DST = SRC1 ^ SRC2.  Return non-zero if DST != SRC1 ^ SRC2.  */
    239 #define bitset_xor_cmp(DST, SRC1, SRC2) BITSET_XOR_CMP_ (DST, SRC1, SRC2)
    240 
    241 
    242 
    243 /* DST = (SRC1 & SRC2) | SRC3.  */
    244 #define bitset_and_or(DST, SRC1, SRC2, SRC3) \
    245  BITSET_AND_OR_ (DST, SRC1, SRC2, SRC3)
    246 
    247 /* DST = (SRC1 & SRC2) | SRC3.  Return non-zero if
    248    DST != (SRC1 & SRC2) | SRC3.  */
    249 #define bitset_and_or_cmp(DST, SRC1, SRC2, SRC3) \
    250  BITSET_AND_OR_CMP_ (DST, SRC1, SRC2, SRC3)
    251 
    252 /* DST = (SRC1 & ~SRC2) | SRC3.  */
    253 #define bitset_andn_or(DST, SRC1, SRC2, SRC3) \
    254  BITSET_ANDN_OR_ (DST, SRC1, SRC2, SRC3)
    255 
    256 /* DST = (SRC1 & ~SRC2) | SRC3.  Return non-zero if
    257    DST != (SRC1 & ~SRC2) | SRC3.  */
    258 #define bitset_andn_or_cmp(DST, SRC1, SRC2, SRC3) \
    259  BITSET_ANDN_OR_CMP_ (DST, SRC1, SRC2, SRC3)
    260 
    261 /* DST = (SRC1 | SRC2) & SRC3.  */
    262 #define bitset_or_and(DST, SRC1, SRC2, SRC3)\
    263  BITSET_OR_AND_ (DST, SRC1, SRC2, SRC3)
    264 
    265 /* DST = (SRC1 | SRC2) & SRC3.  Return non-zero if
    266    DST != (SRC1 | SRC2) & SRC3.  */
    267 #define bitset_or_and_cmp(DST, SRC1, SRC2, SRC3)\
    268  BITSET_OR_AND_CMP_ (DST, SRC1, SRC2, SRC3)
    269 
    270 /* Find list of up to NUM bits set in BSET starting from and including
    271    *NEXT.  Return with actual number of bits found and with *NEXT
    272    indicating where search stopped.  */
    273 #define bitset_list(BSET, LIST, NUM, NEXT) \
    274  BITSET_LIST_ (BSET, LIST, NUM, NEXT)
    275 
    276 /* Find reverse list of up to NUM bits set in BSET starting from and
    277    including NEXT.  Return with actual number of bits found and with
    278    *NEXT indicating where search stopped.  */
    279 #define bitset_list_reverse(BSET, LIST, NUM, NEXT) \
    280  BITSET_LIST_REVERSE_ (BSET, LIST, NUM, NEXT)
    281 
    282 /* Return true if both bitsets are of the same type and size.  */
    283 extern bool bitset_compatible_p (bitset bset1, bitset bset2);
    284 
    285 /* Find next set bit from the given bit index.  */
    286 extern bitset_bindex bitset_next (bitset, bitset_bindex);
    287 
    288 /* Find previous set bit from the given bit index.  */
    289 extern bitset_bindex bitset_prev (bitset, bitset_bindex);
    290 
    291 /* Find first set bit.  */
    292 extern bitset_bindex bitset_first (bitset);
    293 
    294 /* Find last set bit.  */
    295 extern bitset_bindex bitset_last (bitset);
    296 
    297 /* Return nonzero if this is the only set bit.  */
    298 extern bool bitset_only_set_p (bitset, bitset_bindex);
    299 
    300 /* Dump bitset.  */
    301 extern void bitset_dump (FILE *, bitset);
    302 
    303 /* Loop over all elements of BSET, starting with MIN, setting INDEX
    304    to the index of each set bit.  For example, the following will print
    305    the bits set in a bitset:
    306 
    307    bitset_bindex i;
    308    bitset_iterator iter;
    309 
    310    BITSET_FOR_EACH (iter, src, i, 0)
    311    {
    312       printf ("%lu ", (unsigned long int) i);
    313    };
    314 */
    315 #define BITSET_FOR_EACH(ITER, BSET, INDEX, MIN)				      \
    316   for (ITER.next = (MIN), ITER.num = BITSET_LIST_SIZE;			      \
    317        (ITER.num == BITSET_LIST_SIZE)					      \
    318        && (ITER.num = bitset_list (BSET, ITER.list,			      \
    319 				   BITSET_LIST_SIZE, &ITER.next));)	      \
    320     for (ITER.i = 0;							      \
    321 	 ITER.i < ITER.num && ((INDEX) = ITER.list[ITER.i], 1);		      \
    322 	 ITER.i++)
    323 
    324 
    325 /* Loop over all elements of BSET, in reverse order starting with
    326    MIN, setting INDEX to the index of each set bit.  For example, the
    327    following will print the bits set in a bitset in reverse order:
    328 
    329    bitset_bindex i;
    330    bitset_iterator iter;
    331 
    332    BITSET_FOR_EACH_REVERSE (iter, src, i, 0)
    333    {
    334       printf ("%lu ", (unsigned long int) i);
    335    };
    336 */
    337 #define BITSET_FOR_EACH_REVERSE(ITER, BSET, INDEX, MIN)			      \
    338   for (ITER.next = (MIN), ITER.num = BITSET_LIST_SIZE;			      \
    339        (ITER.num == BITSET_LIST_SIZE)					      \
    340        && (ITER.num = bitset_list_reverse (BSET, ITER.list,		      \
    341 					   BITSET_LIST_SIZE, &ITER.next));)   \
    342     for (ITER.i = 0;							      \
    343 	 ITER.i < ITER.num && ((INDEX) = ITER.list[ITER.i], 1);		      \
    344 	 ITER.i++)
    345 
    346 
    347 /* Define set operations in terms of logical operations.  */
    348 
    349 #define bitset_diff(DST, SRC1, SRC2) bitset_andn (DST, SRC1, SRC2)
    350 #define bitset_diff_cmp(DST, SRC1, SRC2) bitset_andn_cmp (DST, SRC1, SRC2)
    351 
    352 #define bitset_intersection(DST, SRC1, SRC2) bitset_and (DST, SRC1, SRC2)
    353 #define bitset_intersection_cmp(DST, SRC1, SRC2) bitset_and_cmp (DST, SRC1, SRC2)
    354 
    355 #define bitset_union(DST, SRC1, SRC2) bitset_or (DST, SRC1, SRC2)
    356 #define bitset_union_cmp(DST, SRC1, SRC2) bitset_or_cmp (DST, SRC1, SRC2)
    357 
    358 /* Symmetrical difference.  */
    359 #define bitset_symdiff(DST, SRC1, SRC2) bitset_xor (DST, SRC1, SRC2)
    360 #define bitset_symdiff_cmp(DST, SRC1, SRC2) bitset_xor_cmp (DST, SRC1, SRC2)
    361 
    362 /* Union of difference.  */
    363 #define bitset_diff_union(DST, SRC1, SRC2, SRC3) \
    364   bitset_andn_or (DST, SRC1, SRC2, SRC3)
    365 #define bitset_diff_union_cmp(DST, SRC1, SRC2, SRC3) \
    366   bitset_andn_or_cmp (DST, SRC1, SRC2, SRC3)
    367 
    368 
    369 /* Release any memory tied up with bitsets.  */
    370 extern void bitset_release_memory (void);
    371 
    372 /* Enable bitset stats gathering.  */
    373 extern void bitset_stats_enable (void);
    374 
    375 /* Disable bitset stats gathering.  */
    376 extern void bitset_stats_disable (void);
    377 
    378 /* Read bitset stats file of accummulated stats.  */
    379 void bitset_stats_read (const char *file_name);
    380 
    381 /* Write bitset stats file of accummulated stats.  */
    382 void bitset_stats_write (const char *file_name);
    383 
    384 /* Dump bitset stats.  */
    385 extern void bitset_stats_dump (FILE *);
    386 
    387 /* Function to debug bitset from debugger.  */
    388 extern void debug_bitset (bitset);
    389 
    390 /* Function to debug bitset stats from debugger.  */
    391 extern void debug_bitset_stats (void);
    392 
    393 #endif /* _BITSET_H  */
    394