]> git.saurik.com Git - bison.git/blob - lib/bbitset.h
build: avoid warning from coverity about lbitset_elt_find
[bison.git] / lib / bbitset.h
1 /* Base bitset stuff.
2
3 Copyright (C) 2002-2004, 2006, 2009-2012 Free Software Foundation,
4 Inc.
5
6 Contributed by Michael Hayes (m.hayes@elec.canterbury.ac.nz).
7
8 This program is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20
21 #ifndef _BBITSET_H
22 #define _BBITSET_H
23
24 #include "libiberty.h"
25
26 #include <stdbool.h>
27 #include <limits.h>
28 #include <stddef.h>
29
30 /* Currently we support five flavours of bitsets:
31 BITSET_ARRAY: Array of bits (fixed size, fast for dense bitsets).
32 Memory for bit array and bitset structure allocated
33 contiguously.
34 BITSET_LIST: Linked list of arrays of bits (variable size, least storage
35 for large very sparse sets).
36 BITSET_TABLE: Expandable table of pointers to arrays of bits
37 (variable size, less storage for large sparse sets).
38 Faster than BITSET_LIST for random access.
39 BITSET_VARRAY: Variable array of bits (variable size, fast for
40 dense bitsets).
41 BITSET_STATS: Wrapper bitset for internal use only. Used for gathering
42 statistics and/or better run-time checking.
43 */
44 enum bitset_type {BITSET_ARRAY, BITSET_LIST, BITSET_TABLE, BITSET_VARRAY,
45 BITSET_TYPE_NUM, BITSET_STATS};
46 #define BITSET_TYPE_NAMES {"abitset", "lbitset", "ebitset", "vbitset"}
47
48 extern const char * const bitset_type_names[];
49
50 enum bitset_alloc_type {BITSET_MALLOC, BITSET_OBALLOC};
51
52 /* Data type used to store a word of bits. */
53 typedef unsigned long int bitset_word;
54 #define BITSET_WORD_BITS ((unsigned int) (CHAR_BIT * sizeof (bitset_word)))
55
56 /* Bit index. In theory we might need a type wider than size_t, but
57 in practice we lose at most a factor of CHAR_BIT by going with
58 size_t, and that is good enough. If this type is changed to be
59 wider than size_t, the code needs to be modified to check for
60 overflow when converting bit counts to byte or word counts.
61 The bit and word index types must be unsigned. */
62 typedef size_t bitset_bindex;
63
64 /* Word index. */
65 typedef size_t bitset_windex;
66
67 /* Maximum values for commonly-used unsigned types. BITSET_SIZE_MAX
68 always equals SIZE_MAX, but some older systems lack SIZE_MAX. */
69 #define BITSET_BINDEX_MAX ((bitset_bindex) -1)
70
71 /* Limit max word index to the maximum value of a signed integer
72 to simplify cache disabling. */
73 #define BITSET_WINDEX_MAX (((bitset_windex) -1) >> 1)
74 #define BITSET_SIZE_MAX ((size_t) -1)
75
76 #define BITSET_MSB ((bitset_word) 1 << (BITSET_WORD_BITS - 1))
77
78 #define BITSET_LIST_SIZE 1024
79
80 enum bitset_ops {BITSET_OP_ZERO, BITSET_OP_ONES,
81 BITSET_OP_COPY, BITSET_OP_NOT,
82 BITSET_OP_EMPTY_P, BITSET_OP_EQUAL_P,
83 BITSET_OP_SUBSET_P, BITSET_OP_DISJOINT_P,
84 BITSET_OP_AND, BITSET_OP_OR, BITSET_OP_XOR, BITSET_OP_ANDN,
85 BITSET_OP_OR_AND, BITSET_OP_AND_OR, BITSET_OP_ANDN_OR};
86
87 struct bbitset_struct
88 {
89 const struct bitset_vtable *vtable;
90 bitset_windex cindex; /* Cache word index. */
91 bitset_windex csize; /* Cache size in words. */
92 bitset_word *cdata; /* Cache data pointer. */
93 bitset_bindex n_bits; /* Number of bits. */
94 /* Perhaps we could sacrifice another word to indicate
95 that the bitset is known to be zero, that a bit has been set
96 in the cache, and that a bit has been cleared in the cache.
97 This would speed up some of the searches but slightly slow down
98 bit set/reset operations of cached bits. */
99 };
100
101
102 typedef union bitset_union *bitset;
103
104
105 /* Private accessor macros to bitset structure. */
106 #define BITSET_VTABLE_(SRC) (SRC)->b.vtable
107 #define BITSET_CINDEX_(SRC) (SRC)->b.cindex
108 #define BITSET_CDATA_(SRC) (SRC)->b.cdata
109 #define BITSET_CSIZE_(SRC) (SRC)->b.csize
110 #define BITSET_NBITS_(SRC) (SRC)->b.n_bits
111
112
113 /* The contents of this structure should be considered private. */
114 struct bitset_vtable
115 {
116 void (*set) (bitset, bitset_bindex);
117 void (*reset) (bitset, bitset_bindex);
118 bool (*toggle) (bitset, bitset_bindex);
119 bool (*test) (bitset, bitset_bindex);
120 bitset_bindex (*resize) (bitset, bitset_bindex);
121 bitset_bindex (*size) (bitset);
122 bitset_bindex (*count) (bitset);
123
124 bool (*empty_p) (bitset);
125 void (*ones) (bitset);
126 void (*zero) (bitset);
127
128 void (*copy) (bitset, bitset);
129 bool (*disjoint_p) (bitset, bitset);
130 bool (*equal_p) (bitset, bitset);
131 void (*not_) (bitset, bitset);
132 bool (*subset_p) (bitset, bitset);
133
134 void (*and_) (bitset, bitset, bitset);
135 bool (*and_cmp) (bitset, bitset, bitset);
136 void (*andn) (bitset, bitset, bitset);
137 bool (*andn_cmp) (bitset, bitset, bitset);
138 void (*or_) (bitset, bitset, bitset);
139 bool (*or_cmp) (bitset, bitset, bitset);
140 void (*xor_) (bitset, bitset, bitset);
141 bool (*xor_cmp) (bitset, bitset, bitset);
142
143 void (*and_or) (bitset, bitset, bitset, bitset);
144 bool (*and_or_cmp) (bitset, bitset, bitset, bitset);
145 void (*andn_or) (bitset, bitset, bitset, bitset);
146 bool (*andn_or_cmp) (bitset, bitset, bitset, bitset);
147 void (*or_and) (bitset, bitset, bitset, bitset);
148 bool (*or_and_cmp) (bitset, bitset, bitset, bitset);
149
150 bitset_bindex (*list) (bitset, bitset_bindex *, bitset_bindex,
151 bitset_bindex *);
152 bitset_bindex (*list_reverse) (bitset, bitset_bindex *, bitset_bindex,
153 bitset_bindex *);
154 void (*free) (bitset);
155 enum bitset_type type;
156 };
157
158 #define BITSET_COMPATIBLE_(BSET1, BSET2) \
159 ((BSET1)->b.vtable == (BSET2)->b.vtable)
160
161 #define BITSET_CHECK2_(DST, SRC) \
162 if (!BITSET_COMPATIBLE_ (DST, SRC)) abort ();
163
164 #define BITSET_CHECK3_(DST, SRC1, SRC2) \
165 if (!BITSET_COMPATIBLE_ (DST, SRC1) \
166 || !BITSET_COMPATIBLE_ (DST, SRC2)) abort ();
167
168 #define BITSET_CHECK4_(DST, SRC1, SRC2, SRC3) \
169 if (!BITSET_COMPATIBLE_ (DST, SRC1) || !BITSET_COMPATIBLE_ (DST, SRC2) \
170 || !BITSET_COMPATIBLE_ (DST, SRC3)) abort ();
171
172
173 /* Redefine number of bits in bitset DST. */
174 #define BITSET_RESIZE_(DST, SIZE) (DST)->b.vtable->resize (DST, SIZE)
175
176 /* Return size in bits of bitset SRC. */
177 #define BITSET_SIZE_(SRC) (SRC)->b.vtable->size (SRC)
178
179 /* Return number of bits set in bitset SRC. */
180 #define BITSET_COUNT_(SRC) (SRC)->b.vtable->count (SRC)
181
182 /* Return type of bitset SRC. */
183 #define BITSET_TYPE_(DST) (DST)->b.vtable->type
184
185 /* Set bit BITNO in bitset DST. */
186 #define BITSET_SET_(DST, BITNO) (DST)->b.vtable->set (DST, BITNO)
187
188 /* Reset bit BITNO in bitset DST. */
189 #define BITSET_RESET_(DST, BITNO) (DST)->b.vtable->reset (DST, BITNO)
190
191 /* Toggle bit BITNO in bitset DST. */
192 #define BITSET_TOGGLE_(DST, BITNO) (DST)->b.vtable->toggle (DST, BITNO)
193
194 /* Return non-zero if bit BITNO in bitset SRC is set. */
195 #define BITSET_TEST_(SRC, BITNO) (SRC)->b.vtable->test (SRC, BITNO)
196
197 /* Free bitset SRC. */
198 #define BITSET_FREE_(SRC)\
199 ((SRC)->b.vtable->free ? (SRC)->b.vtable->free (SRC) :(void)0)
200
201
202 /* Return SRC == 0. */
203 #define BITSET_EMPTY_P_(SRC) (SRC)->b.vtable->empty_p (SRC)
204
205 /* DST = ~0. */
206 #define BITSET_ONES_(DST) (DST)->b.vtable->ones (DST)
207
208 /* DST = 0. */
209 #define BITSET_ZERO_(DST) (DST)->b.vtable->zero (DST)
210
211
212
213 /* DST = SRC. */
214 #define BITSET_COPY_(DST, SRC) (SRC)->b.vtable->copy (DST, SRC)
215
216 /* Return DST & SRC == 0. */
217 #define BITSET_DISJOINT_P_(DST, SRC) (SRC)->b.vtable->disjoint_p (DST, SRC)
218
219 /* Return DST == SRC. */
220 #define BITSET_EQUAL_P_(DST, SRC) (SRC)->b.vtable->equal_p (DST, SRC)
221
222 /* DST = ~SRC. */
223 #define BITSET_NOT_(DST, SRC) (SRC)->b.vtable->not_ (DST, SRC)
224
225 /* Return DST == DST | SRC. */
226 #define BITSET_SUBSET_P_(DST, SRC) (SRC)->b.vtable->subset_p (DST, SRC)
227
228
229 /* DST = SRC1 & SRC2. */
230 #define BITSET_AND_(DST, SRC1, SRC2) (SRC1)->b.vtable->and_ (DST, SRC1, SRC2)
231 #define BITSET_AND_CMP_(DST, SRC1, SRC2) (SRC1)->b.vtable->and_cmp (DST, SRC1, SRC2)
232
233 /* DST = SRC1 & ~SRC2. */
234 #define BITSET_ANDN_(DST, SRC1, SRC2) (SRC1)->b.vtable->andn (DST, SRC1, SRC2)
235 #define BITSET_ANDN_CMP_(DST, SRC1, SRC2) (SRC1)->b.vtable->andn_cmp (DST, SRC1, SRC2)
236
237 /* DST = SRC1 | SRC2. */
238 #define BITSET_OR_(DST, SRC1, SRC2) (SRC1)->b.vtable->or_ (DST, SRC1, SRC2)
239 #define BITSET_OR_CMP_(DST, SRC1, SRC2) (SRC1)->b.vtable->or_cmp (DST, SRC1, SRC2)
240
241 /* DST = SRC1 ^ SRC2. */
242 #define BITSET_XOR_(DST, SRC1, SRC2) (SRC1)->b.vtable->xor_ (DST, SRC1, SRC2)
243 #define BITSET_XOR_CMP_(DST, SRC1, SRC2) (SRC1)->b.vtable->xor_cmp (DST, SRC1, SRC2)
244
245
246
247 /* DST = (SRC1 & SRC2) | SRC3. Return non-zero if
248 DST != (SRC1 & SRC2) | SRC3. */
249 #define BITSET_AND_OR_(DST, SRC1, SRC2, SRC3) \
250 (SRC1)->b.vtable->and_or (DST, SRC1, SRC2, SRC3)
251 #define BITSET_AND_OR_CMP_(DST, SRC1, SRC2, SRC3) \
252 (SRC1)->b.vtable->and_or_cmp (DST, SRC1, SRC2, SRC3)
253
254 /* DST = (SRC1 & ~SRC2) | SRC3. Return non-zero if
255 DST != (SRC1 & ~SRC2) | SRC3. */
256 #define BITSET_ANDN_OR_(DST, SRC1, SRC2, SRC3) \
257 (SRC1)->b.vtable->andn_or (DST, SRC1, SRC2, SRC3)
258 #define BITSET_ANDN_OR_CMP_(DST, SRC1, SRC2, SRC3) \
259 (SRC1)->b.vtable->andn_or_cmp (DST, SRC1, SRC2, SRC3)
260
261 /* DST = (SRC1 | SRC2) & SRC3. Return non-zero if
262 DST != (SRC1 | SRC2) & SRC3. */
263 #define BITSET_OR_AND_(DST, SRC1, SRC2, SRC3) \
264 (SRC1)->b.vtable->or_and (DST, SRC1, SRC2, SRC3)
265 #define BITSET_OR_AND_CMP_(DST, SRC1, SRC2, SRC3) \
266 (SRC1)->b.vtable->or_and_cmp (DST, SRC1, SRC2, SRC3)
267
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 (BSET)->b.vtable->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 (BSET)->b.vtable->list_reverse (BSET, LIST, NUM, NEXT)
280
281
282 /* Private functions for bitset implementations. */
283
284 extern bool bitset_toggle_ (bitset, bitset_bindex);
285
286 extern bitset_bindex bitset_count_ (bitset);
287
288 extern bitset_bindex bitset_size_ (bitset);
289
290 extern bool bitset_copy_ (bitset, bitset);
291
292 extern void bitset_and_or_ (bitset, bitset, bitset, bitset);
293
294 extern bool bitset_and_or_cmp_ (bitset, bitset, bitset, bitset);
295
296 extern void bitset_andn_or_ (bitset, bitset, bitset, bitset);
297
298 extern bool bitset_andn_or_cmp_ (bitset, bitset, bitset, bitset);
299
300 extern void bitset_or_and_ (bitset, bitset, bitset, bitset);
301
302 extern bool bitset_or_and_cmp_ (bitset, bitset, bitset, bitset);
303
304 #endif /* _BBITSET_H */