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"
44 #if defined(__GNUC__) && defined(__i386__)
45 #include "bitset_ia32.h"
48 typedef struct _bitset_t {
53 #define BS_UNIT_SIZE sizeof(bitset_unit_t)
54 #define BS_UNIT_SIZE_BITS (BS_UNIT_SIZE * 8)
55 #define BS_UNIT_MASK (BS_UNIT_SIZE_BITS - 1)
57 #define BS_DATA(bs) ((bitset_unit_t *) ((char *) (bs) + sizeof(bitset_t)))
58 #define BS_UNITS(bits) (round_up2(bits, BS_UNIT_SIZE_BITS) / BS_UNIT_SIZE_BITS)
59 #define BS_TOTAL_SIZE(bits) (sizeof(bitset_t) + BS_UNITS(bits) * BS_UNIT_SIZE)
62 * Initialize a bitset.
63 * This functions should not be called.
65 * Note that this function needs three macros which must be provided by the
66 * bitfield implementor:
67 * - _bitset_overall_size(size) The overall size that must be
68 * allocated for the bitfield in bytes.
69 * - _bitset_units(size) The number of units that will be
70 * present in the bitfield for a given highest bit.
71 * - _bitset_data_ptr(data, size) This produces as pointer to the
72 * first unit in the allocated memory area. The main reason for this
73 * macro is, that some bitset implementors want control over memory
76 * @param area A pointer to memory reserved for the bitset.
77 * @param size The size of the bitset in bits.
78 * @return A pointer to the initialized bitset.
80 static INLINE bitset_t *_bitset_prepare(void *area, bitset_pos_t size)
82 bitset_t *__attribute((aligned(4))) ptr = area;
83 memset(ptr, 0, BS_TOTAL_SIZE(size));
84 ptr->units = BS_UNITS(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)[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, BS_TOTAL_SIZE(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(BS_TOTAL_SIZE(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(BS_TOTAL_SIZE(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->size && "Bit to large");
160 return BS_DATA(bs) + bit / BS_UNIT_SIZE_BITS;
164 * Set a bit in the bitset.
165 * @param bs The bitset.
166 * @param bit The bit to set.
168 static INLINE void bitset_set(bitset_t *bs, bitset_pos_t bit)
170 bitset_unit_t *unit = _bitset_get_unit(bs, bit);
171 _bitset_inside_set(unit, bit & BS_UNIT_MASK);
175 * Clear a bit in the bitset.
176 * @param bs The bitset.
177 * @param bit The bit to clear.
179 static INLINE void bitset_clear(bitset_t *bs, bitset_pos_t bit)
181 bitset_unit_t *unit = _bitset_get_unit(bs, bit);
182 _bitset_inside_clear(unit, bit & BS_UNIT_MASK);
186 * Check, if a bit is set.
187 * @param bs The bitset.
188 * @param bit The bit to check for.
189 * @return 1, if the bit was set, 0 if not.
191 static INLINE int bitset_is_set(const bitset_t *bs, bitset_pos_t bit)
193 bitset_unit_t *unit = _bitset_get_unit(bs, bit);
194 return _bitset_inside_is_set(unit, bit & BS_UNIT_MASK);
198 * Flip a bit in a bitset.
199 * @param bs The bitset.
200 * @param bit The bit to flip.
202 static INLINE void bitset_flip(bitset_t *bs, bitset_pos_t bit)
204 bitset_unit_t *unit = _bitset_get_unit(bs, bit);
205 _bitset_inside_flip(unit, bit & BS_UNIT_MASK);
209 * Flip the whole bitset.
210 * @param bs The bitset.
212 static INLINE void bitset_flip_all(bitset_t *bs)
215 for(i = 0; i < bs->units; i++)
216 _bitset_inside_flip_unit(&BS_DATA(bs)[i]);
217 _bitset_mask_highest(bs);
221 * Copy a bitset to another.
222 * @param tgt The target bitset.
223 * @param src The source bitset.
224 * @return The target bitset.
226 static INLINE bitset_t *bitset_copy(bitset_t *tgt, const bitset_t *src)
228 bitset_pos_t tu = tgt->units;
229 bitset_pos_t su = src->units;
230 bitset_pos_t min_units = tu < su ? tu : su;
231 memcpy(BS_DATA(tgt), BS_DATA(src), min_units * BS_UNIT_SIZE);
233 memset(BS_DATA(tgt) + min_units, 0, BS_UNIT_SIZE * (tu - min_units));
234 return _bitset_mask_highest(tgt);
238 * Find the next set bit from a given bit.
239 * @note Note that if pos is set, pos is returned.
240 * @param bs The bitset.
241 * @param pos The bit from which to search for the next set bit.
242 * @return The next set bit from pos on, or -1, if no set bit was found
245 static INLINE bitset_pos_t _bitset_next(const bitset_t *bs,
246 bitset_pos_t pos, int set)
248 bitset_pos_t unit_number = pos / BS_UNIT_SIZE_BITS;
255 bitset_pos_t bit_in_unit = pos & BS_UNIT_MASK;
256 bitset_pos_t in_unit_mask = (1 << bit_in_unit) - 1;
259 * Mask out the bits smaller than pos in the current unit.
260 * We are only interested in bits set higher than pos.
262 bitset_unit_t curr_unit = BS_DATA(bs)[unit_number];
265 * Find the next bit set in the unit.
266 * Mind that this function returns 0, if the unit is -1 and
267 * counts the bits from 1 on.
269 bitset_pos_t next_in_this_unit =
270 _bitset_inside_ntz_value((set ? curr_unit : ~curr_unit) & ~in_unit_mask);
272 /* If there is a bit set in the current unit, exit. */
273 if (next_in_this_unit < BS_UNIT_SIZE_BITS) {
274 res = next_in_this_unit + unit_number * BS_UNIT_SIZE_BITS;
275 return res < bs->size ? res : (bitset_pos_t) -1;
278 /* Else search for set bits in the next units. */
281 for(i = unit_number + 1; i < bs->units; ++i) {
282 bitset_unit_t data = BS_DATA(bs)[i];
283 bitset_pos_t first_set =
284 _bitset_inside_ntz_value(set ? data : ~data);
286 if (first_set < BS_UNIT_SIZE_BITS) {
287 res = first_set + i * BS_UNIT_SIZE_BITS;
288 return res < bs->size ? res : (bitset_pos_t) -1;
297 #define bitset_next_clear(bs,pos) _bitset_next((bs), (pos), 0)
298 #define bitset_next_set(bs,pos) _bitset_next((bs), (pos), 1)
301 * Convenience macro for bitset iteration.
302 * @param bitset The bitset.
303 * @param elm A unsigned long variable.
305 #define bitset_foreach(bitset,elm) \
306 for(elm = bitset_next_set(bitset,0); elm != (bitset_pos_t) -1; elm = bitset_next_set(bitset,elm+1))
309 #define bitset_foreach_clear(bitset,elm) \
310 for(elm = bitset_next_clear(bitset,0); elm != (bitset_pos_t) -1; elm = bitset_next_clear(bitset,elm+1))
313 * Count the bits set.
314 * This can also be seen as the cardinality of the set.
315 * @param bs The bitset.
316 * @return The number of bits set in the bitset.
318 static INLINE unsigned bitset_popcnt(const bitset_t *bs)
324 for (i = 0, unit = BS_DATA(bs); i < bs->units; ++i, ++unit)
325 pop += _bitset_inside_pop(unit);
332 * This sets all bits to zero.
333 * @param bs The bitset.
335 static INLINE bitset_t *bitset_clear_all(bitset_t *bs)
337 memset(BS_DATA(bs), 0, BS_UNIT_SIZE * bs->units);
343 * This sets all bits to one.
344 * @param bs The bitset.
346 static INLINE bitset_t *bitset_set_all(bitset_t *bs)
348 memset(BS_DATA(bs), -1, bs->units * BS_UNIT_SIZE);
349 return _bitset_mask_highest(bs);
353 * Check, if one bitset is contained by another.
354 * That is, each bit set in lhs is also set in rhs.
355 * @param lhs A bitset.
356 * @param rhs Another bitset.
357 * @return 1, if all bits in lhs are also set in rhs, 0 otherwise.
359 static INLINE int bitset_contains(const bitset_t *lhs, const bitset_t *rhs)
361 bitset_pos_t n = lhs->units < rhs->units ? lhs->units : rhs->units;
364 for(i = 0; i < n; ++i) {
365 bitset_unit_t lu = BS_DATA(lhs)[i];
366 bitset_unit_t ru = BS_DATA(rhs)[i];
373 * If the left hand sinde is a larger bitset than rhs,
374 * we have to check, that all extra bits in lhs are 0
377 for(i = n; i < lhs->units; ++i) {
378 if(BS_DATA(lhs)[i] != 0)
387 * Treat the bitset as a number and subtract 1.
388 * @param bs The bitset.
389 * @return The same bitset.
391 static INLINE void bitset_minus1(bitset_t *bs)
393 #define _SH (sizeof(bitset_unit_t) * 8 - 1)
397 for(i = 0; i < bs->units; ++i) {
398 bitset_unit_t unit = BS_DATA(bs)[i];
399 bitset_unit_t um1 = unit - 1;
401 BS_DATA(bs)[i] = um1;
403 if(((unit >> _SH) ^ (um1 >> _SH)) == 0)
410 * Check if two bitsets intersect.
411 * @param a The first bitset.
412 * @param b The second bitset.
413 * @return 1 if they have a bit in common, 0 if not.
415 static INLINE int bitset_intersect(const bitset_t *a, const bitset_t *b)
417 bitset_pos_t n = a->units < b->units ? a->units : b->units;
420 for (i = 0; i < n; ++i)
421 if (BS_DATA(a)[i] & BS_DATA(b)[i])
428 * Check, if a bitset is empty.
429 * @param a The bitset.
430 * @return 1, if the bitset is empty, 0 if not.
432 static INLINE int bitset_is_empty(const bitset_t *a)
435 for (i = 0; i < a->units; ++i)
436 if (BS_DATA(a)[i] != 0)
442 * Print a bitset to a stream.
443 * The bitset is printed as a comma separated list of bits set.
444 * @param file The stream.
445 * @param bs The bitset.
447 static INLINE void bitset_fprint(FILE *file, const bitset_t *bs)
449 const char *prefix = "";
453 for(i = bitset_next_set(bs, 0); i != -1; i = bitset_next_set(bs, i + 1)) {
454 fprintf(file, "%s%u", prefix, i);
460 static INLINE void bitset_debug_fprint(FILE *file, const bitset_t *bs)
464 fprintf(file, "%u:", bs->units);
465 for(i = 0; i < bs->units; ++i)
466 fprintf(file, " " BITSET_UNIT_FMT, BS_DATA(bs)[i]);
470 * Perform tgt = tgt \ src operation.
471 * @param tgt The target bitset.
472 * @param src The source bitset.
473 * @return the tgt set.
475 static INLINE bitset_t *bitset_andnot(bitset_t *tgt, const bitset_t *src);
478 * Perform Union, tgt = tgt u src operation.
479 * @param tgt The target bitset.
480 * @param src The source bitset.
481 * @return the tgt set.
483 static INLINE bitset_t *bitset_or(bitset_t *tgt, const bitset_t *src);
486 * Perform tgt = tgt ^ ~src operation.
487 * @param tgt The target bitset.
488 * @param src The source bitset.
489 * @return the tgt set.
491 static INLINE bitset_t *bitset_xor(bitset_t *tgt, const bitset_t *src);
494 * Here, the binary operations follow.
495 * And, Or, And Not, Xor are available.
497 #define BINARY_OP(op) \
498 static INLINE bitset_t *bitset_ ## op(bitset_t *tgt, const bitset_t *src) \
501 bitset_pos_t n = tgt->units > src->units ? src->units : tgt->units; \
502 for(i = 0; i < n; i += _BITSET_BINOP_UNITS_INC) \
503 _bitset_inside_binop_ ## op(&BS_DATA(tgt)[i], &BS_DATA(src)[i]); \
505 _bitset_clear_rest(&BS_DATA(tgt)[i], tgt->units - i); \
506 return _bitset_mask_highest(tgt); \
510 * Define the clear rest macro for the and, since it is the only case,
511 * were non existed (treated as 0) units in the src must be handled.
512 * For all other operations holds: x Op 0 = x for Op in { Andnot, Or, Xor }
514 * For and, each bitset implementer has to provide the macro
515 * _bitset_clear_units(data, n), which clears n units from the pointer
518 #define _bitset_clear_rest(data,n) _bitset_inside_clear_units(data, n)
520 #undef _bitset_clear_rest
521 #define _bitset_clear_rest(data,n) do { } while(0)