1170 lines
28 KiB
C
1170 lines
28 KiB
C
/* Functions to support expandable bitsets.
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Copyright (C) 2002-2006, 2009-2015, 2018-2021 Free Software Foundation, Inc.
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Contributed by Michael Hayes (m.hayes@elec.canterbury.ac.nz).
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <https://www.gnu.org/licenses/>. */
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#include <config.h>
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#include "bitset/table.h"
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#include <stdlib.h>
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#include <string.h>
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#include "obstack.h"
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#include "xalloc.h"
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/* This file implements expandable bitsets. These bitsets can be of
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arbitrary length and are more efficient than arrays of bits for
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large sparse sets.
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Empty elements are represented by a NULL pointer in the table of
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element pointers. An alternative is to point to a special zero
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element. Similarly, we could represent an all 1's element with
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another special ones element pointer.
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Bitsets are commonly empty so we need to ensure that this special
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case is fast. A zero bitset is indicated when cdata is 0. This is
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conservative since cdata may be non zero and the bitset may still
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be zero.
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The bitset cache can be disabled either by setting cindex to
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BITSET_WINDEX_MAX or by setting csize to 0. Here
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we use the former approach since cindex needs to be updated whenever
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cdata is changed.
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*/
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/* Number of words to use for each element. */
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#define TBITSET_ELT_WORDS 2
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/* Number of bits stored in each element. */
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#define TBITSET_ELT_BITS \
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((unsigned) (TBITSET_ELT_WORDS * BITSET_WORD_BITS))
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/* Tbitset element. We use an array of bits. */
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typedef struct tbitset_elt_struct
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{
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union
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{
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bitset_word words[TBITSET_ELT_WORDS]; /* Bits that are set. */
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struct tbitset_elt_struct *next;
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}
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u;
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}
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tbitset_elt;
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typedef tbitset_elt *tbitset_elts;
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/* Number of elements to initially allocate. */
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#ifndef TBITSET_INITIAL_SIZE
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# define TBITSET_INITIAL_SIZE 2
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#endif
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enum tbitset_find_mode
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{ TBITSET_FIND, TBITSET_CREATE, TBITSET_SUBST };
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static tbitset_elt tbitset_zero_elts[1]; /* Elements of all zero bits. */
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/* Obstack to allocate bitset elements from. */
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static struct obstack tbitset_obstack;
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static bool tbitset_obstack_init = false;
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static tbitset_elt *tbitset_free_list; /* Free list of bitset elements. */
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#define TBITSET_N_ELTS(N) (((N) + TBITSET_ELT_BITS - 1) / TBITSET_ELT_BITS)
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#define TBITSET_ELTS(BSET) ((BSET)->e.elts)
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#define TBITSET_SIZE(BSET) TBITSET_N_ELTS (BITSET_NBITS_ (BSET))
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#define TBITSET_ASIZE(BSET) ((BSET)->e.size)
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#define TBITSET_NEXT(ELT) ((ELT)->u.next)
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#define TBITSET_WORDS(ELT) ((ELT)->u.words)
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/* Disable bitset cache and mark BSET as being zero. */
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#define TBITSET_ZERO_SET(BSET) ((BSET)->b.cindex = BITSET_WINDEX_MAX, \
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(BSET)->b.cdata = 0)
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#define TBITSET_CACHE_DISABLE(BSET) ((BSET)->b.cindex = BITSET_WINDEX_MAX)
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/* Disable bitset cache and mark BSET as being possibly non-zero. */
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#define TBITSET_NONZERO_SET(BSET) \
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(TBITSET_CACHE_DISABLE (BSET), (BSET)->b.cdata = (bitset_word *)~0)
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/* A conservative estimate of whether the bitset is zero.
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This is non-zero only if we know for sure that the bitset is zero. */
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#define TBITSET_ZERO_P(BSET) ((BSET)->b.cdata == 0)
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/* Enable cache to point to element with table index EINDEX.
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The element must exist. */
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#define TBITSET_CACHE_SET(BSET, EINDEX) \
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((BSET)->b.cindex = (EINDEX) * TBITSET_ELT_WORDS, \
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(BSET)->b.cdata = TBITSET_WORDS (TBITSET_ELTS (BSET) [EINDEX]))
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#undef min
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#undef max
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#define min(a, b) ((a) > (b) ? (b) : (a))
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#define max(a, b) ((a) > (b) ? (a) : (b))
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static bitset_bindex
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tbitset_resize (bitset src, bitset_bindex n_bits)
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{
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if (n_bits == BITSET_NBITS_ (src))
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return n_bits;
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bitset_windex oldsize = TBITSET_SIZE (src);
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bitset_windex newsize = TBITSET_N_ELTS (n_bits);
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if (oldsize < newsize)
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{
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/* The bitset needs to grow. If we already have enough memory
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allocated, then just zero what we need. */
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if (newsize > TBITSET_ASIZE (src))
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{
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/* We need to allocate more memory. When oldsize is
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non-zero this means that we are changing the size, so
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grow the bitset 25% larger than requested to reduce
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number of reallocations. */
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bitset_windex size = oldsize == 0 ? newsize : newsize + newsize / 4;
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TBITSET_ELTS (src)
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= xrealloc (TBITSET_ELTS (src), size * sizeof (tbitset_elt *));
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TBITSET_ASIZE (src) = size;
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}
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memset (TBITSET_ELTS (src) + oldsize, 0,
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(newsize - oldsize) * sizeof (tbitset_elt *));
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}
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else
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{
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/* The bitset needs to shrink. There's no point deallocating
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the memory unless it is shrinking by a reasonable amount. */
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if ((oldsize - newsize) >= oldsize / 2)
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{
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void *p
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= realloc (TBITSET_ELTS (src), newsize * sizeof (tbitset_elt *));
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if (p)
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{
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TBITSET_ELTS (src) = p;
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TBITSET_ASIZE (src) = newsize;
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}
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}
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/* Need to prune any excess bits. FIXME. */
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}
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BITSET_NBITS_ (src) = n_bits;
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return n_bits;
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}
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/* Allocate a tbitset element. The bits are not cleared. */
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static inline tbitset_elt *
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tbitset_elt_alloc (void)
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{
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tbitset_elt *elt;
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if (tbitset_free_list != 0)
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{
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elt = tbitset_free_list;
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tbitset_free_list = TBITSET_NEXT (elt);
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}
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else
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{
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if (!tbitset_obstack_init)
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{
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tbitset_obstack_init = true;
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/* Let particular systems override the size of a chunk. */
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#ifndef OBSTACK_CHUNK_SIZE
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# define OBSTACK_CHUNK_SIZE 0
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#endif
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/* Let them override the alloc and free routines too. */
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#ifndef OBSTACK_CHUNK_ALLOC
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# define OBSTACK_CHUNK_ALLOC xmalloc
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#endif
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#ifndef OBSTACK_CHUNK_FREE
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# define OBSTACK_CHUNK_FREE free
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#endif
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#if !(defined __GNUC__ || defined __clang__)
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# define __alignof__(type) 0
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#endif
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obstack_specify_allocation (&tbitset_obstack, OBSTACK_CHUNK_SIZE,
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__alignof__ (tbitset_elt),
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OBSTACK_CHUNK_ALLOC,
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OBSTACK_CHUNK_FREE);
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}
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/* Perhaps we should add a number of new elements to the free
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list. */
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elt = (tbitset_elt *) obstack_alloc (&tbitset_obstack,
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sizeof (tbitset_elt));
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}
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return elt;
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}
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/* Allocate a tbitset element. The bits are cleared. */
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static inline tbitset_elt *
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tbitset_elt_calloc (void)
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{
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tbitset_elt *elt = tbitset_elt_alloc ();
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memset (TBITSET_WORDS (elt), 0, sizeof (TBITSET_WORDS (elt)));
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return elt;
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}
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static inline void
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tbitset_elt_free (tbitset_elt *elt)
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{
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TBITSET_NEXT (elt) = tbitset_free_list;
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tbitset_free_list = elt;
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}
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/* Remove element with index EINDEX from bitset BSET. */
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static inline void
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tbitset_elt_remove (bitset bset, bitset_windex eindex)
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{
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tbitset_elts *elts = TBITSET_ELTS (bset);
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tbitset_elt *elt = elts[eindex];
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elts[eindex] = 0;
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tbitset_elt_free (elt);
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}
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/* Add ELT into elts at index EINDEX of bitset BSET. */
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static inline void
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tbitset_elt_add (bitset bset, tbitset_elt *elt, bitset_windex eindex)
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{
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tbitset_elts *elts = TBITSET_ELTS (bset);
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/* Assume that the elts entry not allocated. */
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elts[eindex] = elt;
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}
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/* Are all bits in an element zero? */
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static inline bool
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tbitset_elt_zero_p (tbitset_elt *elt)
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{
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for (int i = 0; i < TBITSET_ELT_WORDS; i++)
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if (TBITSET_WORDS (elt)[i])
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return false;
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return true;
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}
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static tbitset_elt *
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tbitset_elt_find (bitset bset, bitset_bindex bindex,
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enum tbitset_find_mode mode)
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{
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bitset_windex eindex = bindex / TBITSET_ELT_BITS;
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tbitset_elts *elts = TBITSET_ELTS (bset);
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bitset_windex size = TBITSET_SIZE (bset);
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if (eindex < size)
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{
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tbitset_elt *elt = elts[eindex];
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if (elt)
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{
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if (TBITSET_WORDS (elt) != bset->b.cdata)
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TBITSET_CACHE_SET (bset, eindex);
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return elt;
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}
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}
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/* The element could not be found. */
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switch (mode)
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{
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default:
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abort ();
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case TBITSET_FIND:
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return NULL;
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case TBITSET_CREATE:
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if (eindex >= size)
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tbitset_resize (bset, bindex);
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/* Create a new element. */
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{
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tbitset_elt *elt = tbitset_elt_calloc ();
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tbitset_elt_add (bset, elt, eindex);
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TBITSET_CACHE_SET (bset, eindex);
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return elt;
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}
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case TBITSET_SUBST:
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return &tbitset_zero_elts[0];
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}
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}
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/* Weed out the zero elements from the elts. */
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static inline bitset_windex
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tbitset_weed (bitset bset)
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{
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if (TBITSET_ZERO_P (bset))
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return 0;
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tbitset_elts *elts = TBITSET_ELTS (bset);
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bitset_windex count = 0;
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bitset_windex j;
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for (j = 0; j < TBITSET_SIZE (bset); j++)
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{
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tbitset_elt *elt = elts[j];
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if (elt)
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{
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if (tbitset_elt_zero_p (elt))
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{
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tbitset_elt_remove (bset, j);
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count++;
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}
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}
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else
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count++;
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}
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count = j - count;
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if (!count)
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{
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/* All the bits are zero. We could shrink the elts.
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For now just mark BSET as known to be zero. */
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TBITSET_ZERO_SET (bset);
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}
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else
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TBITSET_NONZERO_SET (bset);
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return count;
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}
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/* Set all bits in the bitset to zero. */
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static inline void
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tbitset_zero (bitset bset)
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{
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if (TBITSET_ZERO_P (bset))
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return;
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tbitset_elts *elts = TBITSET_ELTS (bset);
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for (bitset_windex j = 0; j < TBITSET_SIZE (bset); j++)
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{
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tbitset_elt *elt = elts[j];
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if (elt)
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tbitset_elt_remove (bset, j);
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}
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/* All the bits are zero. We could shrink the elts.
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For now just mark BSET as known to be zero. */
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TBITSET_ZERO_SET (bset);
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}
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static inline bool
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tbitset_equal_p (bitset dst, bitset src)
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{
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if (src == dst)
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return true;
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tbitset_weed (dst);
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tbitset_weed (src);
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if (TBITSET_SIZE (src) != TBITSET_SIZE (dst))
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return false;
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tbitset_elts *selts = TBITSET_ELTS (src);
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tbitset_elts *delts = TBITSET_ELTS (dst);
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for (bitset_windex j = 0; j < TBITSET_SIZE (src); j++)
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{
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tbitset_elt *selt = selts[j];
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tbitset_elt *delt = delts[j];
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if (!selt && !delt)
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continue;
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if ((selt && !delt) || (!selt && delt))
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return false;
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for (unsigned i = 0; i < TBITSET_ELT_WORDS; i++)
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if (TBITSET_WORDS (selt)[i] != TBITSET_WORDS (delt)[i])
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return false;
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}
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return true;
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}
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/* Copy bits from bitset SRC to bitset DST. */
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static inline void
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tbitset_copy_ (bitset dst, bitset src)
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{
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if (src == dst)
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return;
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tbitset_zero (dst);
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if (BITSET_NBITS_ (dst) != BITSET_NBITS_ (src))
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tbitset_resize (dst, BITSET_NBITS_ (src));
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tbitset_elts *selts = TBITSET_ELTS (src);
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tbitset_elts *delts = TBITSET_ELTS (dst);
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for (bitset_windex j = 0; j < TBITSET_SIZE (src); j++)
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{
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tbitset_elt *selt = selts[j];
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if (selt)
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{
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tbitset_elt *tmp = tbitset_elt_alloc ();
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delts[j] = tmp;
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memcpy (TBITSET_WORDS (tmp), TBITSET_WORDS (selt),
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sizeof (TBITSET_WORDS (selt)));
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}
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}
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TBITSET_NONZERO_SET (dst);
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}
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/* Copy bits from bitset SRC to bitset DST. Return true if
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bitsets different. */
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static inline bool
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tbitset_copy_cmp (bitset dst, bitset src)
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{
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if (src == dst)
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return false;
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if (TBITSET_ZERO_P (dst))
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{
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tbitset_copy_ (dst, src);
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return !TBITSET_ZERO_P (src);
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}
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if (tbitset_equal_p (dst, src))
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return false;
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tbitset_copy_ (dst, src);
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return true;
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}
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/* Set bit BITNO in bitset DST. */
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static void
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tbitset_set (bitset dst, bitset_bindex bitno)
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{
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bitset_windex windex = bitno / BITSET_WORD_BITS;
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tbitset_elt_find (dst, bitno, TBITSET_CREATE);
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dst->b.cdata[windex - dst->b.cindex] |=
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(bitset_word) 1 << (bitno % BITSET_WORD_BITS);
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}
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/* Reset bit BITNO in bitset DST. */
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static void
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tbitset_reset (bitset dst, bitset_bindex bitno)
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{
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bitset_windex windex = bitno / BITSET_WORD_BITS;
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if (!tbitset_elt_find (dst, bitno, TBITSET_FIND))
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return;
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dst->b.cdata[windex - dst->b.cindex] &=
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~((bitset_word) 1 << (bitno % BITSET_WORD_BITS));
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/* If all the data is zero, perhaps we should remove it now...
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However, there is a good chance that the element will be needed
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again soon. */
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}
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/* Test bit BITNO in bitset SRC. */
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static bool
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tbitset_test (bitset src, bitset_bindex bitno)
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{
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bitset_windex windex = bitno / BITSET_WORD_BITS;
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return (tbitset_elt_find (src, bitno, TBITSET_FIND)
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&& ((src->b.cdata[windex - src->b.cindex]
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>> (bitno % BITSET_WORD_BITS))
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& 1));
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}
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static void
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tbitset_free (bitset bset)
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{
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tbitset_zero (bset);
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free (TBITSET_ELTS (bset));
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}
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/* Find list of up to NUM bits set in BSET starting from and including
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*NEXT and store in array LIST. Return with actual number of bits
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found and with *NEXT indicating where search stopped. */
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static bitset_bindex
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tbitset_list_reverse (bitset bset, bitset_bindex *list,
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bitset_bindex num, bitset_bindex *next)
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{
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if (TBITSET_ZERO_P (bset))
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return 0;
|
|
|
|
bitset_windex size = TBITSET_SIZE (bset);
|
|
bitset_bindex n_bits = size * TBITSET_ELT_BITS;
|
|
bitset_bindex rbitno = *next;
|
|
|
|
if (rbitno >= n_bits)
|
|
return 0;
|
|
|
|
tbitset_elts *elts = TBITSET_ELTS (bset);
|
|
|
|
bitset_bindex bitno = n_bits - (rbitno + 1);
|
|
|
|
bitset_windex windex = bitno / BITSET_WORD_BITS;
|
|
bitset_windex eindex = bitno / TBITSET_ELT_BITS;
|
|
bitset_windex woffset = windex - eindex * TBITSET_ELT_WORDS;
|
|
|
|
/* If num is 1, we could speed things up with a binary search
|
|
of the word of interest. */
|
|
bitset_bindex count = 0;
|
|
unsigned bitcnt = bitno % BITSET_WORD_BITS;
|
|
bitset_bindex bitoff = windex * BITSET_WORD_BITS;
|
|
|
|
do
|
|
{
|
|
tbitset_elt *elt = elts[eindex];
|
|
if (elt)
|
|
{
|
|
bitset_word *srcp = TBITSET_WORDS (elt);
|
|
|
|
do
|
|
{
|
|
bitset_word word = srcp[woffset];
|
|
if (bitcnt + 1 < BITSET_WORD_BITS)
|
|
/* We're starting in the middle of a word: smash bits to ignore. */
|
|
word &= ((bitset_word) 1 << (bitcnt + 1)) - 1;
|
|
BITSET_FOR_EACH_BIT_REVERSE(pos, word)
|
|
{
|
|
list[count++] = bitoff + pos;
|
|
if (count >= num)
|
|
{
|
|
*next = n_bits - (bitoff + pos);
|
|
return count;
|
|
}
|
|
}
|
|
bitoff -= BITSET_WORD_BITS;
|
|
bitcnt = BITSET_WORD_BITS - 1;
|
|
}
|
|
while (woffset--);
|
|
}
|
|
|
|
woffset = TBITSET_ELT_WORDS - 1;
|
|
bitoff = eindex * TBITSET_ELT_BITS - BITSET_WORD_BITS;
|
|
}
|
|
while (eindex--);
|
|
|
|
*next = n_bits - (bitoff + 1);
|
|
return count;
|
|
}
|
|
|
|
|
|
/* Find list of up to NUM bits set in BSET starting from and including
|
|
*NEXT and store in array LIST. Return with actual number of bits
|
|
found and with *NEXT indicating where search stopped. */
|
|
static bitset_bindex
|
|
tbitset_list (bitset bset, bitset_bindex *list,
|
|
bitset_bindex num, bitset_bindex *next)
|
|
{
|
|
if (TBITSET_ZERO_P (bset))
|
|
return 0;
|
|
|
|
bitset_bindex bitno = *next;
|
|
bitset_bindex count = 0;
|
|
|
|
tbitset_elts *elts = TBITSET_ELTS (bset);
|
|
bitset_windex size = TBITSET_SIZE (bset);
|
|
bitset_windex eindex = bitno / TBITSET_ELT_BITS;
|
|
|
|
if (bitno % TBITSET_ELT_BITS)
|
|
{
|
|
/* We need to start within an element. This is not very common. */
|
|
tbitset_elt *elt = elts[eindex];
|
|
if (elt)
|
|
{
|
|
bitset_word *srcp = TBITSET_WORDS (elt);
|
|
bitset_windex woffset = eindex * TBITSET_ELT_WORDS;
|
|
|
|
for (bitset_windex windex = bitno / BITSET_WORD_BITS;
|
|
(windex - woffset) < TBITSET_ELT_WORDS; windex++)
|
|
{
|
|
bitset_word word = srcp[windex - woffset] >> (bitno % BITSET_WORD_BITS);
|
|
|
|
BITSET_FOR_EACH_BIT (pos, word)
|
|
{
|
|
list[count++] = bitno + pos;
|
|
if (count >= num)
|
|
{
|
|
*next = bitno + pos + 1;
|
|
return count;
|
|
}
|
|
}
|
|
bitno = (windex + 1) * BITSET_WORD_BITS;
|
|
}
|
|
}
|
|
|
|
/* Skip to next element. */
|
|
eindex++;
|
|
}
|
|
|
|
/* If num is 1, we could speed things up with a binary search
|
|
of the word of interest. */
|
|
|
|
for (; eindex < size; eindex++)
|
|
{
|
|
tbitset_elt *elt = elts[eindex];
|
|
if (!elt)
|
|
continue;
|
|
|
|
bitset_word *srcp = TBITSET_WORDS (elt);
|
|
bitset_windex windex = eindex * TBITSET_ELT_WORDS;
|
|
bitno = windex * BITSET_WORD_BITS;
|
|
|
|
/* Is there enough room to avoid checking in each iteration? */
|
|
if ((count + TBITSET_ELT_BITS) < num)
|
|
{
|
|
/* The coast is clear, plant boot! */
|
|
|
|
#if TBITSET_ELT_WORDS == 2
|
|
bitset_word word = srcp[0];
|
|
if (word)
|
|
BITSET_FOR_EACH_BIT (pos, word)
|
|
list[count++] = bitno + pos;
|
|
windex++;
|
|
bitno = windex * BITSET_WORD_BITS;
|
|
|
|
word = srcp[1];
|
|
if (word)
|
|
BITSET_FOR_EACH_BIT (pos, word)
|
|
list[count++] = bitno + pos;
|
|
windex++;
|
|
bitno = windex * BITSET_WORD_BITS;
|
|
#else
|
|
for (int i = 0; i < TBITSET_ELT_WORDS; i++, windex++)
|
|
{
|
|
bitset_word word = srcp[i];
|
|
if (word)
|
|
BITSET_FOR_EACH_BIT (pos, word)
|
|
list[count++] = bitno + pos;
|
|
bitno = windex * BITSET_WORD_BITS;
|
|
}
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
/* Tread more carefully since we need to check
|
|
if array overflows. */
|
|
for (int i = 0; i < TBITSET_ELT_WORDS; i++)
|
|
{
|
|
bitset_word word = srcp[i];
|
|
if (word)
|
|
BITSET_FOR_EACH_BIT (pos, word)
|
|
{
|
|
list[count++] = bitno + pos;
|
|
if (count >= num)
|
|
{
|
|
*next = bitno + pos + 1;
|
|
return count;
|
|
}
|
|
}
|
|
windex++;
|
|
bitno = windex * BITSET_WORD_BITS;
|
|
}
|
|
}
|
|
}
|
|
|
|
*next = bitno;
|
|
return count;
|
|
}
|
|
|
|
|
|
/* Ensure that any unused bits within the last element are clear. */
|
|
static inline void
|
|
tbitset_unused_clear (bitset dst)
|
|
{
|
|
bitset_bindex n_bits = BITSET_NBITS_ (dst);
|
|
unsigned last_bit = n_bits % TBITSET_ELT_BITS;
|
|
|
|
if (last_bit)
|
|
{
|
|
tbitset_elts *elts = TBITSET_ELTS (dst);
|
|
|
|
bitset_windex eindex = n_bits / TBITSET_ELT_BITS;
|
|
|
|
tbitset_elt *elt = elts[eindex];
|
|
if (elt)
|
|
{
|
|
bitset_word *srcp = TBITSET_WORDS (elt);
|
|
|
|
bitset_windex windex = n_bits / BITSET_WORD_BITS;
|
|
bitset_windex woffset = eindex * TBITSET_ELT_WORDS;
|
|
|
|
srcp[windex - woffset]
|
|
&= ((bitset_word) 1 << (last_bit % BITSET_WORD_BITS)) - 1;
|
|
windex++;
|
|
for (; (windex - woffset) < TBITSET_ELT_WORDS; windex++)
|
|
srcp[windex - woffset] = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
static void
|
|
tbitset_ones (bitset dst)
|
|
{
|
|
for (bitset_windex j = 0; j < TBITSET_SIZE (dst); j++)
|
|
{
|
|
/* Create new elements if they cannot be found. Perhaps
|
|
we should just add pointers to a ones element? */
|
|
tbitset_elt *elt =
|
|
tbitset_elt_find (dst, j * TBITSET_ELT_BITS, TBITSET_CREATE);
|
|
memset (TBITSET_WORDS (elt), -1, sizeof (TBITSET_WORDS (elt)));
|
|
}
|
|
TBITSET_NONZERO_SET (dst);
|
|
tbitset_unused_clear (dst);
|
|
}
|
|
|
|
|
|
static bool
|
|
tbitset_empty_p (bitset dst)
|
|
{
|
|
if (TBITSET_ZERO_P (dst))
|
|
return true;
|
|
|
|
tbitset_elts *elts = TBITSET_ELTS (dst);
|
|
for (bitset_windex j = 0; j < TBITSET_SIZE (dst); j++)
|
|
{
|
|
tbitset_elt *elt = elts[j];
|
|
|
|
if (elt)
|
|
{
|
|
if (!tbitset_elt_zero_p (elt))
|
|
return false;
|
|
/* Do some weeding as we go. */
|
|
tbitset_elt_remove (dst, j);
|
|
}
|
|
}
|
|
|
|
/* All the bits are zero. We could shrink the elts.
|
|
For now just mark DST as known to be zero. */
|
|
TBITSET_ZERO_SET (dst);
|
|
return true;
|
|
}
|
|
|
|
|
|
static void
|
|
tbitset_not (bitset dst, bitset src)
|
|
{
|
|
tbitset_resize (dst, BITSET_NBITS_ (src));
|
|
|
|
for (bitset_windex j = 0; j < TBITSET_SIZE (src); j++)
|
|
{
|
|
/* Create new elements for dst if they cannot be found
|
|
or substitute zero elements if src elements not found. */
|
|
tbitset_elt *selt =
|
|
tbitset_elt_find (src, j * TBITSET_ELT_BITS, TBITSET_SUBST);
|
|
tbitset_elt *delt =
|
|
tbitset_elt_find (dst, j * TBITSET_ELT_BITS, TBITSET_CREATE);
|
|
|
|
for (unsigned i = 0; i < TBITSET_ELT_WORDS; i++)
|
|
TBITSET_WORDS (delt)[i] = ~TBITSET_WORDS (selt)[i];
|
|
}
|
|
TBITSET_NONZERO_SET (dst);
|
|
tbitset_unused_clear (dst);
|
|
}
|
|
|
|
|
|
/* Is DST == DST | SRC? */
|
|
static bool
|
|
tbitset_subset_p (bitset dst, bitset src)
|
|
{
|
|
tbitset_elts *selts = TBITSET_ELTS (src);
|
|
tbitset_elts *delts = TBITSET_ELTS (dst);
|
|
|
|
bitset_windex ssize = TBITSET_SIZE (src);
|
|
bitset_windex dsize = TBITSET_SIZE (dst);
|
|
|
|
for (bitset_windex j = 0; j < ssize; j++)
|
|
{
|
|
tbitset_elt *selt = j < ssize ? selts[j] : 0;
|
|
tbitset_elt *delt = j < dsize ? delts[j] : 0;
|
|
|
|
if (!selt && !delt)
|
|
continue;
|
|
|
|
if (!selt)
|
|
selt = &tbitset_zero_elts[0];
|
|
if (!delt)
|
|
delt = &tbitset_zero_elts[0];
|
|
|
|
for (unsigned i = 0; i < TBITSET_ELT_WORDS; i++)
|
|
if (TBITSET_WORDS (delt)[i]
|
|
!= (TBITSET_WORDS (selt)[i] | TBITSET_WORDS (delt)[i]))
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
/* Is DST & SRC == 0? */
|
|
static bool
|
|
tbitset_disjoint_p (bitset dst, bitset src)
|
|
{
|
|
tbitset_elts *selts = TBITSET_ELTS (src);
|
|
tbitset_elts *delts = TBITSET_ELTS (dst);
|
|
|
|
bitset_windex ssize = TBITSET_SIZE (src);
|
|
bitset_windex dsize = TBITSET_SIZE (dst);
|
|
|
|
for (bitset_windex j = 0; j < ssize; j++)
|
|
{
|
|
tbitset_elt *selt = j < ssize ? selts[j] : 0;
|
|
tbitset_elt *delt = j < dsize ? delts[j] : 0;
|
|
|
|
if (!selt || !delt)
|
|
continue;
|
|
|
|
for (unsigned i = 0; i < TBITSET_ELT_WORDS; i++)
|
|
if ((TBITSET_WORDS (selt)[i] & TBITSET_WORDS (delt)[i]))
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
|
|
static bool
|
|
tbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op)
|
|
{
|
|
bool changed = false;
|
|
|
|
tbitset_resize (dst, max (BITSET_NBITS_ (src1), BITSET_NBITS_ (src2)));
|
|
|
|
bitset_windex ssize1 = TBITSET_SIZE (src1);
|
|
bitset_windex ssize2 = TBITSET_SIZE (src2);
|
|
bitset_windex dsize = TBITSET_SIZE (dst);
|
|
bitset_windex size = ssize1;
|
|
if (size < ssize2)
|
|
size = ssize2;
|
|
|
|
tbitset_elts *selts1 = TBITSET_ELTS (src1);
|
|
tbitset_elts *selts2 = TBITSET_ELTS (src2);
|
|
tbitset_elts *delts = TBITSET_ELTS (dst);
|
|
|
|
bitset_windex j = 0;
|
|
for (j = 0; j < size; j++)
|
|
{
|
|
tbitset_elt *selt1 = j < ssize1 ? selts1[j] : 0;
|
|
tbitset_elt *selt2 = j < ssize2 ? selts2[j] : 0;
|
|
tbitset_elt *delt = j < dsize ? delts[j] : 0;
|
|
|
|
if (!selt1 && !selt2)
|
|
{
|
|
if (delt)
|
|
{
|
|
changed = true;
|
|
tbitset_elt_remove (dst, j);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
if (!selt1)
|
|
selt1 = &tbitset_zero_elts[0];
|
|
if (!selt2)
|
|
selt2 = &tbitset_zero_elts[0];
|
|
if (!delt)
|
|
delt = tbitset_elt_calloc ();
|
|
else
|
|
delts[j] = 0;
|
|
|
|
bitset_word *srcp1 = TBITSET_WORDS (selt1);
|
|
bitset_word *srcp2 = TBITSET_WORDS (selt2);
|
|
bitset_word *dstp = TBITSET_WORDS (delt);
|
|
switch (op)
|
|
{
|
|
default:
|
|
abort ();
|
|
|
|
case BITSET_OP_OR:
|
|
for (unsigned i = 0; i < TBITSET_ELT_WORDS; i++, dstp++)
|
|
{
|
|
bitset_word tmp = *srcp1++ | *srcp2++;
|
|
|
|
if (*dstp != tmp)
|
|
{
|
|
changed = true;
|
|
*dstp = tmp;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case BITSET_OP_AND:
|
|
for (unsigned i = 0; i < TBITSET_ELT_WORDS; i++, dstp++)
|
|
{
|
|
bitset_word tmp = *srcp1++ & *srcp2++;
|
|
|
|
if (*dstp != tmp)
|
|
{
|
|
changed = true;
|
|
*dstp = tmp;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case BITSET_OP_XOR:
|
|
for (unsigned i = 0; i < TBITSET_ELT_WORDS; i++, dstp++)
|
|
{
|
|
bitset_word tmp = *srcp1++ ^ *srcp2++;
|
|
|
|
if (*dstp != tmp)
|
|
{
|
|
changed = true;
|
|
*dstp = tmp;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case BITSET_OP_ANDN:
|
|
for (unsigned i = 0; i < TBITSET_ELT_WORDS; i++, dstp++)
|
|
{
|
|
bitset_word tmp = *srcp1++ & ~(*srcp2++);
|
|
|
|
if (*dstp != tmp)
|
|
{
|
|
changed = true;
|
|
*dstp = tmp;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
if (!tbitset_elt_zero_p (delt))
|
|
tbitset_elt_add (dst, delt, j);
|
|
else
|
|
tbitset_elt_free (delt);
|
|
}
|
|
|
|
/* If we have elements of DST left over, free them all. */
|
|
for (; j < dsize; j++)
|
|
{
|
|
changed = true;
|
|
|
|
tbitset_elt *delt = delts[j];
|
|
if (delt)
|
|
tbitset_elt_remove (dst, j);
|
|
}
|
|
|
|
TBITSET_NONZERO_SET (dst);
|
|
return changed;
|
|
}
|
|
|
|
|
|
static bool
|
|
tbitset_and_cmp (bitset dst, bitset src1, bitset src2)
|
|
{
|
|
if (TBITSET_ZERO_P (src2))
|
|
{
|
|
tbitset_weed (dst);
|
|
bool changed = TBITSET_ZERO_P (dst);
|
|
tbitset_zero (dst);
|
|
return changed;
|
|
}
|
|
else if (TBITSET_ZERO_P (src1))
|
|
{
|
|
tbitset_weed (dst);
|
|
bool changed = TBITSET_ZERO_P (dst);
|
|
tbitset_zero (dst);
|
|
return changed;
|
|
}
|
|
else
|
|
return tbitset_op3_cmp (dst, src1, src2, BITSET_OP_AND);
|
|
}
|
|
|
|
|
|
static void
|
|
tbitset_and (bitset dst, bitset src1, bitset src2)
|
|
{
|
|
tbitset_and_cmp (dst, src1, src2);
|
|
}
|
|
|
|
|
|
static bool
|
|
tbitset_andn_cmp (bitset dst, bitset src1, bitset src2)
|
|
{
|
|
if (TBITSET_ZERO_P (src2))
|
|
return tbitset_copy_cmp (dst, src1);
|
|
else if (TBITSET_ZERO_P (src1))
|
|
{
|
|
tbitset_weed (dst);
|
|
bool changed = TBITSET_ZERO_P (dst);
|
|
tbitset_zero (dst);
|
|
return changed;
|
|
}
|
|
else
|
|
return tbitset_op3_cmp (dst, src1, src2, BITSET_OP_ANDN);
|
|
}
|
|
|
|
|
|
static void
|
|
tbitset_andn (bitset dst, bitset src1, bitset src2)
|
|
{
|
|
tbitset_andn_cmp (dst, src1, src2);
|
|
}
|
|
|
|
|
|
static bool
|
|
tbitset_or_cmp (bitset dst, bitset src1, bitset src2)
|
|
{
|
|
if (TBITSET_ZERO_P (src2))
|
|
return tbitset_copy_cmp (dst, src1);
|
|
else if (TBITSET_ZERO_P (src1))
|
|
return tbitset_copy_cmp (dst, src2);
|
|
else
|
|
return tbitset_op3_cmp (dst, src1, src2, BITSET_OP_OR);
|
|
}
|
|
|
|
|
|
static void
|
|
tbitset_or (bitset dst, bitset src1, bitset src2)
|
|
{
|
|
tbitset_or_cmp (dst, src1, src2);
|
|
}
|
|
|
|
|
|
static bool
|
|
tbitset_xor_cmp (bitset dst, bitset src1, bitset src2)
|
|
{
|
|
if (TBITSET_ZERO_P (src2))
|
|
return tbitset_copy_cmp (dst, src1);
|
|
else if (TBITSET_ZERO_P (src1))
|
|
return tbitset_copy_cmp (dst, src2);
|
|
else
|
|
return tbitset_op3_cmp (dst, src1, src2, BITSET_OP_XOR);
|
|
}
|
|
|
|
|
|
static void
|
|
tbitset_xor (bitset dst, bitset src1, bitset src2)
|
|
{
|
|
tbitset_xor_cmp (dst, src1, src2);
|
|
}
|
|
|
|
|
|
static void
|
|
tbitset_copy (bitset dst, bitset src)
|
|
{
|
|
if (BITSET_COMPATIBLE_ (dst, src))
|
|
tbitset_copy_ (dst, src);
|
|
else
|
|
bitset_copy_ (dst, src);
|
|
}
|
|
|
|
|
|
/* Vector of operations for linked-list bitsets. */
|
|
struct bitset_vtable tbitset_vtable = {
|
|
tbitset_set,
|
|
tbitset_reset,
|
|
bitset_toggle_,
|
|
tbitset_test,
|
|
tbitset_resize,
|
|
bitset_size_,
|
|
bitset_count_,
|
|
tbitset_empty_p,
|
|
tbitset_ones,
|
|
tbitset_zero,
|
|
tbitset_copy,
|
|
tbitset_disjoint_p,
|
|
tbitset_equal_p,
|
|
tbitset_not,
|
|
tbitset_subset_p,
|
|
tbitset_and,
|
|
tbitset_and_cmp,
|
|
tbitset_andn,
|
|
tbitset_andn_cmp,
|
|
tbitset_or,
|
|
tbitset_or_cmp,
|
|
tbitset_xor,
|
|
tbitset_xor_cmp,
|
|
bitset_and_or_,
|
|
bitset_and_or_cmp_,
|
|
bitset_andn_or_,
|
|
bitset_andn_or_cmp_,
|
|
bitset_or_and_,
|
|
bitset_or_and_cmp_,
|
|
tbitset_list,
|
|
tbitset_list_reverse,
|
|
tbitset_free,
|
|
BITSET_TABLE
|
|
};
|
|
|
|
|
|
/* Return size of initial structure. */
|
|
size_t
|
|
tbitset_bytes (MAYBE_UNUSED bitset_bindex n_bits)
|
|
{
|
|
return sizeof (struct tbitset_struct);
|
|
}
|
|
|
|
|
|
/* Initialize a bitset. */
|
|
|
|
bitset
|
|
tbitset_init (bitset bset, bitset_bindex n_bits)
|
|
{
|
|
bset->b.vtable = &tbitset_vtable;
|
|
|
|
bset->b.csize = TBITSET_ELT_WORDS;
|
|
|
|
TBITSET_ZERO_SET (bset);
|
|
|
|
TBITSET_ASIZE (bset) = 0;
|
|
TBITSET_ELTS (bset) = 0;
|
|
tbitset_resize (bset, n_bits);
|
|
|
|
return bset;
|
|
}
|
|
|
|
|
|
void
|
|
tbitset_release_memory (void)
|
|
{
|
|
tbitset_free_list = 0;
|
|
if (tbitset_obstack_init)
|
|
{
|
|
tbitset_obstack_init = false;
|
|
obstack_free (&tbitset_obstack, NULL);
|
|
}
|
|
}
|