2 * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief A bitset implementation.
23 * @author Sebastian Hack
27 #ifndef FIRM_ADT_BITSET_H
28 #define FIRM_ADT_BITSET_H
30 #include "firm_config.h"
38 #include "bitfiddle.h"
40 typedef unsigned int bitset_pos_t;
42 #include "bitset_std.h"
45 #if defined(__GNUC__) && defined(__i386__)
46 #include "bitset_ia32.h"
50 typedef struct _bitset_t {
56 #define BS_UNIT_SIZE sizeof(bitset_unit_t)
57 #define BS_UNIT_SIZE_BITS (BS_UNIT_SIZE * 8)
58 #define BS_UNIT_MASK (BS_UNIT_SIZE_BITS - 1)
61 * Initialize a bitset.
62 * This functions should not be called.
64 * Note that this function needs three macros which must be provided by the
65 * bitfield implementor:
66 * - _bitset_overall_size(size) The overall size that must be
67 * allocated for the bitfield in bytes.
68 * - _bitset_units(size) The number of units that will be
69 * present in the bitfield for a given highest bit.
70 * - _bitset_data_ptr(data, size) This produces as pointer to the
71 * first unit in the allocated memory area. The main reason for this
72 * macro is, that some bitset implementors want control over memory
75 * @param area A pointer to memory reserved for the bitset.
76 * @param size The size of the bitset in bits.
77 * @return A pointer to the initialized bitset.
79 static INLINE bitset_t *_bitset_prepare(void *area, bitset_pos_t size)
82 memset(area, 0, _bitset_overall_size(sizeof(bitset_t), size));
83 ptr->units = _bitset_units(size);
85 ptr->data = _bitset_data_ptr(area, sizeof(bitset_t), size);
90 * Mask out all bits, which are only there, because the number
91 * of bits in the set didn't match a unit size boundary.
92 * @param bs The bitset.
93 * @return The masked bitset.
95 static INLINE bitset_t *_bitset_mask_highest(bitset_t *bs)
97 bitset_pos_t rest = bs->size & BS_UNIT_MASK;
99 bs->data[bs->units - 1] &= (1 << rest) - 1;
104 * Get the capacity of the bitset in bits.
105 * @param bs The bitset.
106 * @return The capacity in bits of the bitset.
108 #define bitset_capacity(bs) ((bs)->units * BS_UNIT_SIZE_BITS)
111 * Get the size of the bitset in bits.
112 * @note Note the difference between capacity and size.
113 * @param bs The bitset.
114 * @return The highest bit which can be set or cleared plus 1.
116 #define bitset_size(bs) ((bs)->size)
119 * Allocate a bitset on an obstack.
120 * @param obst The obstack.
121 * @param size The greatest bit that shall be stored in the set.
122 * @return A pointer to an empty initialized bitset.
124 #define bitset_obstack_alloc(obst,size) \
125 _bitset_prepare(obstack_alloc(obst, _bitset_overall_size(sizeof(bitset_t), size)), size)
128 * Allocate a bitset via malloc.
129 * @param size The greatest bit that shall be stored in the set.
130 * @return A pointer to an empty initialized bitset.
132 #define bitset_malloc(size) \
133 _bitset_prepare(xmalloc(_bitset_overall_size(sizeof(bitset_t), size)), size)
136 * Free a bitset allocated with bitset_malloc().
137 * @param bs The bitset.
139 #define bitset_free(bs) free(bs)
142 * Allocate a bitset on the stack via alloca.
143 * @param size The greatest bit that shall be stored in the set.
144 * @return A pointer to an empty initialized bitset.
146 #define bitset_alloca(size) \
147 _bitset_prepare(alloca(_bitset_overall_size(sizeof(bitset_t), size)), size)
151 * Get the unit which contains a specific bit.
152 * This function is internal.
153 * @param bs The bitset.
154 * @param bit The bit.
155 * @return A pointer to the unit containing the bit.
157 static INLINE bitset_unit_t *_bitset_get_unit(const bitset_t *bs, bitset_pos_t bit)
159 /* assert(bit < bs->units * BS_UNIT_SIZE_BITS && "Bit too large"); */
160 assert(bit <= bs->size && "Bit to large");
161 return bs->data + bit / BS_UNIT_SIZE_BITS;
165 * Set a bit in the bitset.
166 * @param bs The bitset.
167 * @param bit The bit to set.
169 static INLINE void bitset_set(bitset_t *bs, bitset_pos_t bit)
171 bitset_unit_t *unit = _bitset_get_unit(bs, bit);
172 _bitset_inside_set(unit, bit & BS_UNIT_MASK);
176 * Clear a bit in the bitset.
177 * @param bs The bitset.
178 * @param bit The bit to clear.
180 static INLINE void bitset_clear(bitset_t *bs, bitset_pos_t bit)
182 bitset_unit_t *unit = _bitset_get_unit(bs, bit);
183 _bitset_inside_clear(unit, bit & BS_UNIT_MASK);
187 * Check, if a bit is set.
188 * @param bs The bitset.
189 * @param bit The bit to check for.
190 * @return 1, if the bit was set, 0 if not.
192 static INLINE int bitset_is_set(const bitset_t *bs, bitset_pos_t bit)
194 bitset_unit_t *unit = _bitset_get_unit(bs, bit);
195 return _bitset_inside_is_set(unit, bit & BS_UNIT_MASK);
199 * Flip a bit in a bitset.
200 * @param bs The bitset.
201 * @param bit The bit to flip.
203 static INLINE void bitset_flip(bitset_t *bs, bitset_pos_t bit)
205 bitset_unit_t *unit = _bitset_get_unit(bs, bit);
206 _bitset_inside_flip(unit, bit & BS_UNIT_MASK);
210 * Flip the whole bitset.
211 * @param bs The bitset.
213 static INLINE void bitset_flip_all(bitset_t *bs)
216 for(i = 0; i < bs->units; i++)
217 _bitset_inside_flip_unit(&bs->data[i]);
218 _bitset_mask_highest(bs);
222 * Copy a bitset to another.
223 * @param tgt The target bitset.
224 * @param src The source bitset.
225 * @return The target bitset.
227 static INLINE bitset_t *bitset_copy(bitset_t *tgt, const bitset_t *src)
229 bitset_pos_t tu = tgt->units;
230 bitset_pos_t su = src->units;
231 bitset_pos_t min_units = tu < su ? tu : su;
232 memcpy(tgt->data, src->data, min_units * BS_UNIT_SIZE);
234 memset(tgt->data + min_units, 0, BS_UNIT_SIZE * (tu - min_units));
235 return _bitset_mask_highest(tgt);
239 * Find the smallest bit set in the bitset.
240 * @param bs The bitset.
241 * @return The smallest bit set in the bitset.
243 static INLINE bitset_pos_t bitset_min(const bitset_t *bs)
245 bitset_pos_t i, ofs = 0;
247 for(i = 0; i < bs->units; ++i) {
248 bitset_unit_t *unit = &bs->data[i];
249 bitset_pos_t pos = _bitset_inside_ntz(unit);
252 ofs += BS_UNIT_SIZE_BITS;
259 * Find the greatest bit set in the bitset.
260 * @param bs The bitset.
261 * @return The greatest bit set in the bitset.
263 static INLINE bitset_pos_t bitset_max(const bitset_t *bs)
265 bitset_pos_t i, max = 0, ofs = 0;
267 for(i = 0; i < bs->units; ++i) {
268 bitset_unit_t *unit = &bs->data[i];
269 bitset_pos_t pos = _bitset_inside_nlz(unit);
272 ofs += BS_UNIT_SIZE_BITS;
279 * Find the next set bit from a given bit.
280 * @note Note that if pos is set, pos is returned.
281 * @param bs The bitset.
282 * @param pos The bit from which to search for the next set bit.
283 * @return The next set bit from pos on, or -1, if no set bit was found
286 static INLINE bitset_pos_t _bitset_next(const bitset_t *bs,
287 bitset_pos_t pos, int set)
289 bitset_pos_t unit_number = pos / BS_UNIT_SIZE_BITS;
296 bitset_pos_t bit_in_unit = pos & BS_UNIT_MASK;
297 bitset_pos_t in_unit_mask = (1 << bit_in_unit) - 1;
300 * Mask out the bits smaller than pos in the current unit.
301 * We are only interested in bits set higher than pos.
303 bitset_unit_t curr_unit = bs->data[unit_number];
306 * Find the next bit set in the unit.
307 * Mind that this function returns 0, if the unit is -1 and
308 * counts the bits from 1 on.
310 bitset_pos_t next_in_this_unit =
311 _bitset_inside_ntz_value((set ? curr_unit : ~curr_unit) & ~in_unit_mask);
313 /* If there is a bit set in the current unit, exit. */
314 if (next_in_this_unit < BS_UNIT_SIZE_BITS) {
315 res = next_in_this_unit + unit_number * BS_UNIT_SIZE_BITS;
316 return res < bs->size ? res : -1;
319 /* Else search for set bits in the next units. */
322 for(i = unit_number + 1; i < bs->units; ++i) {
323 bitset_unit_t data = bs->data[i];
324 bitset_pos_t first_set =
325 _bitset_inside_ntz_value(set ? data : ~data);
327 if (first_set < BS_UNIT_SIZE_BITS) {
328 res = first_set + i * BS_UNIT_SIZE_BITS;
329 return res < bs->size ? res : -1;
338 #define bitset_next_clear(bs,pos) _bitset_next((bs), (pos), 0)
339 #define bitset_next_set(bs,pos) _bitset_next((bs), (pos), 1)
342 * Convenience macro for bitset iteration.
343 * @param bitset The bitset.
344 * @param elm A unsigned long variable.
346 #define bitset_foreach(bitset,elm) \
347 for(elm = bitset_next_set(bitset,0); elm != -1; elm = bitset_next_set(bitset,elm+1))
350 #define bitset_foreach_clear(bitset,elm) \
351 for(elm = bitset_next_clear(bitset,0); elm != -1; elm = bitset_next_clear(bitset,elm+1))
354 * Count the bits set.
355 * This can also be seen as the cardinality of the set.
356 * @param bs The bitset.
357 * @return The number of bits set in the bitset.
359 static INLINE unsigned bitset_popcnt(const bitset_t *bs)
365 for (i = 0, unit = bs->data; i < bs->units; ++i, ++unit)
366 pop += _bitset_inside_pop(unit);
373 * This sets all bits to zero.
374 * @param bs The bitset.
376 static INLINE bitset_t *bitset_clear_all(bitset_t *bs)
378 memset(bs->data, 0, BS_UNIT_SIZE * bs->units);
384 * This sets all bits to one.
385 * @param bs The bitset.
387 static INLINE bitset_t *bitset_set_all(bitset_t *bs)
389 memset(bs->data, -1, bs->units * BS_UNIT_SIZE);
390 return _bitset_mask_highest(bs);
394 * Check, if one bitset is contained by another.
395 * That is, each bit set in lhs is also set in rhs.
396 * @param lhs A bitset.
397 * @param rhs Another bitset.
398 * @return 1, if all bits in lhs are also set in rhs, 0 otherwise.
400 static INLINE int bitset_contains(const bitset_t *lhs, const bitset_t *rhs)
402 bitset_pos_t n = lhs->units < rhs->units ? lhs->units : rhs->units;
405 for(i = 0; i < n; ++i) {
406 bitset_unit_t lu = lhs->data[i];
407 bitset_unit_t ru = rhs->data[i];
414 * If the left hand sinde is a larger bitset than rhs,
415 * we have to check, that all extra bits in lhs are 0
418 for(i = n; i < lhs->units; ++i) {
419 if(lhs->data[i] != 0)
428 * Treat the bitset as a number and subtract 1.
429 * @param bs The bitset.
430 * @return The same bitset.
432 static INLINE void bitset_minus1(bitset_t *bs)
434 #define _SH (sizeof(bitset_unit_t) * 8 - 1)
438 for(i = 0; i < bs->units; ++i) {
439 bitset_unit_t unit = bs->data[i];
440 bitset_unit_t um1 = unit - 1;
444 if(((unit >> _SH) ^ (um1 >> _SH)) == 0)
451 * Check if two bitsets intersect.
452 * @param a The first bitset.
453 * @param b The second bitset.
454 * @return 1 if they have a bit in common, 0 if not.
456 static INLINE int bitset_intersect(const bitset_t *a, const bitset_t *b)
458 bitset_pos_t n = a->units < b->units ? a->units : b->units;
461 for (i = 0; i < n; ++i)
462 if (a->data[i] & b->data[i])
469 * Check, if a bitset is empty.
470 * @param a The bitset.
471 * @return 1, if the bitset is empty, 0 if not.
473 static INLINE int bitset_is_empty(const bitset_t *a)
476 for (i = 0; i < a->units; ++i)
483 * Print a bitset to a stream.
484 * The bitset is printed as a comma separated list of bits set.
485 * @param file The stream.
486 * @param bs The bitset.
488 static INLINE void bitset_fprint(FILE *file, const bitset_t *bs)
490 const char *prefix = "";
494 for(i = bitset_next_set(bs, 0); i != -1; i = bitset_next_set(bs, i + 1)) {
495 fprintf(file, "%s%u", prefix, i);
501 static INLINE void bitset_debug_fprint(FILE *file, const bitset_t *bs)
505 fprintf(file, "%u:", bs->units);
506 for(i = 0; i < bs->units; ++i)
507 fprintf(file, " " BITSET_UNIT_FMT, bs->data[i]);
511 * Perform tgt = tgt \ src operation.
512 * @param tgt The target bitset.
513 * @param src The source bitset.
514 * @return the tgt set.
516 static INLINE bitset_t *bitset_andnot(bitset_t *tgt, const bitset_t *src);
519 * Perform Union, tgt = tgt u src operation.
520 * @param tgt The target bitset.
521 * @param src The source bitset.
522 * @return the tgt set.
524 static INLINE bitset_t *bitset_or(bitset_t *tgt, const bitset_t *src);
527 * Perform tgt = tgt ^ ~src operation.
528 * @param tgt The target bitset.
529 * @param src The source bitset.
530 * @return the tgt set.
532 static INLINE bitset_t *bitset_xor(bitset_t *tgt, const bitset_t *src);
535 * Here, the binary operations follow.
536 * And, Or, And Not, Xor are available.
538 #define BINARY_OP(op) \
539 static INLINE bitset_t *bitset_ ## op(bitset_t *tgt, const bitset_t *src) \
542 bitset_pos_t n = tgt->units > src->units ? src->units : tgt->units; \
543 for(i = 0; i < n; i += _BITSET_BINOP_UNITS_INC) \
544 _bitset_inside_binop_ ## op(&tgt->data[i], &src->data[i]); \
546 _bitset_clear_rest(&tgt->data[i], tgt->units - i); \
547 return _bitset_mask_highest(tgt); \
551 * Define the clear rest macro for the and, since it is the only case,
552 * were non existed (treated as 0) units in the src must be handled.
553 * For all other operations holds: x Op 0 = x for Op in { Andnot, Or, Xor }
555 * For and, each bitset implementer has to provide the macro
556 * _bitset_clear_units(data, n), which clears n units from the pointer
559 #define _bitset_clear_rest(data,n) _bitset_inside_clear_units(data, n)
561 #undef _bitset_clear_rest
562 #define _bitset_clear_rest(data,n)