2008-05-20 Gary Dismukes <dismukes@adacore.com>
[official-gcc.git] / gcc / bitmap.h
blob2a3b0b4baf8c0651862e5fcb4d07cdd58264c5ec
1 /* Functions to support general ended bitmaps.
2 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
3 2006, 2007 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 #ifndef GCC_BITMAP_H
22 #define GCC_BITMAP_H
23 #include "hashtab.h"
24 #include "statistics.h"
25 #include "obstack.h"
27 /* Fundamental storage type for bitmap. */
29 typedef unsigned long BITMAP_WORD;
30 /* BITMAP_WORD_BITS needs to be unsigned, but cannot contain casts as
31 it is used in preprocessor directives -- hence the 1u. */
32 #define BITMAP_WORD_BITS (CHAR_BIT * SIZEOF_LONG * 1u)
34 /* Number of words to use for each element in the linked list. */
36 #ifndef BITMAP_ELEMENT_WORDS
37 #define BITMAP_ELEMENT_WORDS ((128 + BITMAP_WORD_BITS - 1) / BITMAP_WORD_BITS)
38 #endif
40 /* Number of bits in each actual element of a bitmap. */
42 #define BITMAP_ELEMENT_ALL_BITS (BITMAP_ELEMENT_WORDS * BITMAP_WORD_BITS)
44 /* Obstack for allocating bitmaps and elements from. */
45 typedef struct bitmap_obstack GTY (())
47 struct bitmap_element_def *elements;
48 struct bitmap_head_def *heads;
49 struct obstack GTY ((skip)) obstack;
50 } bitmap_obstack;
52 /* Bitmap set element. We use a linked list to hold only the bits that
53 are set. This allows for use to grow the bitset dynamically without
54 having to realloc and copy a giant bit array.
56 The free list is implemented as a list of lists. There is one
57 outer list connected together by prev fields. Each element of that
58 outer is an inner list (that may consist only of the outer list
59 element) that are connected by the next fields. The prev pointer
60 is undefined for interior elements. This allows
61 bitmap_elt_clear_from to be implemented in unit time rather than
62 linear in the number of elements to be freed. */
64 typedef struct bitmap_element_def GTY(())
66 struct bitmap_element_def *next; /* Next element. */
67 struct bitmap_element_def *prev; /* Previous element. */
68 unsigned int indx; /* regno/BITMAP_ELEMENT_ALL_BITS. */
69 BITMAP_WORD bits[BITMAP_ELEMENT_WORDS]; /* Bits that are set. */
70 } bitmap_element;
72 struct bitmap_descriptor;
73 /* Head of bitmap linked list. gengtype ignores ifdefs, but for
74 statistics we need to add a bitmap descriptor pointer. As it is
75 not collected, we can just GTY((skip)) it. */
77 typedef struct bitmap_head_def GTY(()) {
78 bitmap_element *first; /* First element in linked list. */
79 bitmap_element *current; /* Last element looked at. */
80 unsigned int indx; /* Index of last element looked at. */
81 bitmap_obstack *obstack; /* Obstack to allocate elements from.
82 If NULL, then use ggc_alloc. */
83 #ifdef GATHER_STATISTICS
84 struct bitmap_descriptor GTY((skip)) *desc;
85 #endif
86 } bitmap_head;
88 /* Global data */
89 extern bitmap_element bitmap_zero_bits; /* Zero bitmap element */
90 extern bitmap_obstack bitmap_default_obstack; /* Default bitmap obstack */
92 /* Clear a bitmap by freeing up the linked list. */
93 extern void bitmap_clear (bitmap);
95 /* Copy a bitmap to another bitmap. */
96 extern void bitmap_copy (bitmap, const_bitmap);
98 /* True if two bitmaps are identical. */
99 extern bool bitmap_equal_p (const_bitmap, const_bitmap);
101 /* True if the bitmaps intersect (their AND is non-empty). */
102 extern bool bitmap_intersect_p (const_bitmap, const_bitmap);
104 /* True if the complement of the second intersects the first (their
105 AND_COMPL is non-empty). */
106 extern bool bitmap_intersect_compl_p (const_bitmap, const_bitmap);
108 /* True if MAP is an empty bitmap. */
109 #define bitmap_empty_p(MAP) (!(MAP)->first)
111 /* True if the bitmap has only a single bit set. */
112 extern bool bitmap_single_bit_set_p (const_bitmap);
114 /* Count the number of bits set in the bitmap. */
115 extern unsigned long bitmap_count_bits (const_bitmap);
117 /* Boolean operations on bitmaps. The _into variants are two operand
118 versions that modify the first source operand. The other variants
119 are three operand versions that to not destroy the source bitmaps.
120 The operations supported are &, & ~, |, ^. */
121 extern void bitmap_and (bitmap, const_bitmap, const_bitmap);
122 extern void bitmap_and_into (bitmap, const_bitmap);
123 extern bool bitmap_and_compl (bitmap, const_bitmap, const_bitmap);
124 extern bool bitmap_and_compl_into (bitmap, const_bitmap);
125 #define bitmap_compl_and(DST, A, B) bitmap_and_compl (DST, B, A)
126 extern void bitmap_compl_and_into (bitmap, const_bitmap);
127 extern void bitmap_clear_range (bitmap, unsigned int, unsigned int);
128 extern void bitmap_set_range (bitmap, unsigned int, unsigned int);
129 extern bool bitmap_ior (bitmap, const_bitmap, const_bitmap);
130 extern bool bitmap_ior_into (bitmap, const_bitmap);
131 extern void bitmap_xor (bitmap, const_bitmap, const_bitmap);
132 extern void bitmap_xor_into (bitmap, const_bitmap);
134 /* DST = A | (B & ~C). Return true if DST changes. */
135 extern bool bitmap_ior_and_compl (bitmap DST, const_bitmap A, const_bitmap B, const_bitmap C);
136 /* A |= (B & ~C). Return true if A changes. */
137 extern bool bitmap_ior_and_compl_into (bitmap DST, const_bitmap B, const_bitmap C);
139 /* Clear a single register in a register set. */
140 extern void bitmap_clear_bit (bitmap, int);
142 /* Set a single register in a register set. */
143 extern void bitmap_set_bit (bitmap, int);
145 /* Return true if a register is set in a register set. */
146 extern int bitmap_bit_p (bitmap, int);
148 /* Debug functions to print a bitmap linked list. */
149 extern void debug_bitmap (const_bitmap);
150 extern void debug_bitmap_file (FILE *, const_bitmap);
152 /* Print a bitmap. */
153 extern void bitmap_print (FILE *, const_bitmap, const char *, const char *);
155 /* Initialize and release a bitmap obstack. */
156 extern void bitmap_obstack_initialize (bitmap_obstack *);
157 extern void bitmap_obstack_release (bitmap_obstack *);
158 extern void bitmap_register (bitmap MEM_STAT_DECL);
159 extern void dump_bitmap_statistics (void);
161 /* Initialize a bitmap header. OBSTACK indicates the bitmap obstack
162 to allocate from, NULL for GC'd bitmap. */
164 static inline void
165 bitmap_initialize_stat (bitmap head, bitmap_obstack *obstack MEM_STAT_DECL)
167 head->first = head->current = NULL;
168 head->obstack = obstack;
169 #ifdef GATHER_STATISTICS
170 bitmap_register (head PASS_MEM_STAT);
171 #endif
173 #define bitmap_initialize(h,o) bitmap_initialize_stat (h,o MEM_STAT_INFO)
175 /* Allocate and free bitmaps from obstack, malloc and gc'd memory. */
176 extern bitmap bitmap_obstack_alloc_stat (bitmap_obstack *obstack MEM_STAT_DECL);
177 #define bitmap_obstack_alloc(t) bitmap_obstack_alloc_stat (t MEM_STAT_INFO)
178 extern bitmap bitmap_gc_alloc_stat (ALONE_MEM_STAT_DECL);
179 #define bitmap_gc_alloc() bitmap_gc_alloc_stat (ALONE_MEM_STAT_INFO)
180 extern void bitmap_obstack_free (bitmap);
182 /* A few compatibility/functions macros for compatibility with sbitmaps */
183 #define dump_bitmap(file, bitmap) bitmap_print (file, bitmap, "", "\n")
184 #define bitmap_zero(a) bitmap_clear (a)
185 extern unsigned bitmap_first_set_bit (const_bitmap);
187 /* Compute bitmap hash (for purposes of hashing etc.) */
188 extern hashval_t bitmap_hash(const_bitmap);
190 /* Allocate a bitmap from a bit obstack. */
191 #define BITMAP_ALLOC(OBSTACK) bitmap_obstack_alloc (OBSTACK)
193 /* Allocate a gc'd bitmap. */
194 #define BITMAP_GGC_ALLOC() bitmap_gc_alloc ()
196 /* Do any cleanup needed on a bitmap when it is no longer used. */
197 #define BITMAP_FREE(BITMAP) \
198 ((void)(bitmap_obstack_free (BITMAP), (BITMAP) = NULL))
200 /* Iterator for bitmaps. */
202 typedef struct
204 /* Pointer to the current bitmap element. */
205 bitmap_element *elt1;
207 /* Pointer to 2nd bitmap element when two are involved. */
208 bitmap_element *elt2;
210 /* Word within the current element. */
211 unsigned word_no;
213 /* Contents of the actually processed word. When finding next bit
214 it is shifted right, so that the actual bit is always the least
215 significant bit of ACTUAL. */
216 BITMAP_WORD bits;
217 } bitmap_iterator;
219 /* Initialize a single bitmap iterator. START_BIT is the first bit to
220 iterate from. */
222 static inline void
223 bmp_iter_set_init (bitmap_iterator *bi, const_bitmap map,
224 unsigned start_bit, unsigned *bit_no)
226 bi->elt1 = map->first;
227 bi->elt2 = NULL;
229 /* Advance elt1 until it is not before the block containing start_bit. */
230 while (1)
232 if (!bi->elt1)
234 bi->elt1 = &bitmap_zero_bits;
235 break;
238 if (bi->elt1->indx >= start_bit / BITMAP_ELEMENT_ALL_BITS)
239 break;
240 bi->elt1 = bi->elt1->next;
243 /* We might have gone past the start bit, so reinitialize it. */
244 if (bi->elt1->indx != start_bit / BITMAP_ELEMENT_ALL_BITS)
245 start_bit = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS;
247 /* Initialize for what is now start_bit. */
248 bi->word_no = start_bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS;
249 bi->bits = bi->elt1->bits[bi->word_no];
250 bi->bits >>= start_bit % BITMAP_WORD_BITS;
252 /* If this word is zero, we must make sure we're not pointing at the
253 first bit, otherwise our incrementing to the next word boundary
254 will fail. It won't matter if this increment moves us into the
255 next word. */
256 start_bit += !bi->bits;
258 *bit_no = start_bit;
261 /* Initialize an iterator to iterate over the intersection of two
262 bitmaps. START_BIT is the bit to commence from. */
264 static inline void
265 bmp_iter_and_init (bitmap_iterator *bi, const_bitmap map1, const_bitmap map2,
266 unsigned start_bit, unsigned *bit_no)
268 bi->elt1 = map1->first;
269 bi->elt2 = map2->first;
271 /* Advance elt1 until it is not before the block containing
272 start_bit. */
273 while (1)
275 if (!bi->elt1)
277 bi->elt2 = NULL;
278 break;
281 if (bi->elt1->indx >= start_bit / BITMAP_ELEMENT_ALL_BITS)
282 break;
283 bi->elt1 = bi->elt1->next;
286 /* Advance elt2 until it is not before elt1. */
287 while (1)
289 if (!bi->elt2)
291 bi->elt1 = bi->elt2 = &bitmap_zero_bits;
292 break;
295 if (bi->elt2->indx >= bi->elt1->indx)
296 break;
297 bi->elt2 = bi->elt2->next;
300 /* If we're at the same index, then we have some intersecting bits. */
301 if (bi->elt1->indx == bi->elt2->indx)
303 /* We might have advanced beyond the start_bit, so reinitialize
304 for that. */
305 if (bi->elt1->indx != start_bit / BITMAP_ELEMENT_ALL_BITS)
306 start_bit = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS;
308 bi->word_no = start_bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS;
309 bi->bits = bi->elt1->bits[bi->word_no] & bi->elt2->bits[bi->word_no];
310 bi->bits >>= start_bit % BITMAP_WORD_BITS;
312 else
314 /* Otherwise we must immediately advance elt1, so initialize for
315 that. */
316 bi->word_no = BITMAP_ELEMENT_WORDS - 1;
317 bi->bits = 0;
320 /* If this word is zero, we must make sure we're not pointing at the
321 first bit, otherwise our incrementing to the next word boundary
322 will fail. It won't matter if this increment moves us into the
323 next word. */
324 start_bit += !bi->bits;
326 *bit_no = start_bit;
329 /* Initialize an iterator to iterate over the bits in MAP1 & ~MAP2.
332 static inline void
333 bmp_iter_and_compl_init (bitmap_iterator *bi, const_bitmap map1, const_bitmap map2,
334 unsigned start_bit, unsigned *bit_no)
336 bi->elt1 = map1->first;
337 bi->elt2 = map2->first;
339 /* Advance elt1 until it is not before the block containing start_bit. */
340 while (1)
342 if (!bi->elt1)
344 bi->elt1 = &bitmap_zero_bits;
345 break;
348 if (bi->elt1->indx >= start_bit / BITMAP_ELEMENT_ALL_BITS)
349 break;
350 bi->elt1 = bi->elt1->next;
353 /* Advance elt2 until it is not before elt1. */
354 while (bi->elt2 && bi->elt2->indx < bi->elt1->indx)
355 bi->elt2 = bi->elt2->next;
357 /* We might have advanced beyond the start_bit, so reinitialize for
358 that. */
359 if (bi->elt1->indx != start_bit / BITMAP_ELEMENT_ALL_BITS)
360 start_bit = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS;
362 bi->word_no = start_bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS;
363 bi->bits = bi->elt1->bits[bi->word_no];
364 if (bi->elt2 && bi->elt1->indx == bi->elt2->indx)
365 bi->bits &= ~bi->elt2->bits[bi->word_no];
366 bi->bits >>= start_bit % BITMAP_WORD_BITS;
368 /* If this word is zero, we must make sure we're not pointing at the
369 first bit, otherwise our incrementing to the next word boundary
370 will fail. It won't matter if this increment moves us into the
371 next word. */
372 start_bit += !bi->bits;
374 *bit_no = start_bit;
377 /* Advance to the next bit in BI. We don't advance to the next
378 nonzero bit yet. */
380 static inline void
381 bmp_iter_next (bitmap_iterator *bi, unsigned *bit_no)
383 bi->bits >>= 1;
384 *bit_no += 1;
387 /* Advance to the next nonzero bit of a single bitmap, we will have
388 already advanced past the just iterated bit. Return true if there
389 is a bit to iterate. */
391 static inline bool
392 bmp_iter_set (bitmap_iterator *bi, unsigned *bit_no)
394 /* If our current word is nonzero, it contains the bit we want. */
395 if (bi->bits)
397 next_bit:
398 while (!(bi->bits & 1))
400 bi->bits >>= 1;
401 *bit_no += 1;
403 return true;
406 /* Round up to the word boundary. We might have just iterated past
407 the end of the last word, hence the -1. It is not possible for
408 bit_no to point at the beginning of the now last word. */
409 *bit_no = ((*bit_no + BITMAP_WORD_BITS - 1)
410 / BITMAP_WORD_BITS * BITMAP_WORD_BITS);
411 bi->word_no++;
413 while (1)
415 /* Find the next nonzero word in this elt. */
416 while (bi->word_no != BITMAP_ELEMENT_WORDS)
418 bi->bits = bi->elt1->bits[bi->word_no];
419 if (bi->bits)
420 goto next_bit;
421 *bit_no += BITMAP_WORD_BITS;
422 bi->word_no++;
425 /* Advance to the next element. */
426 bi->elt1 = bi->elt1->next;
427 if (!bi->elt1)
428 return false;
429 *bit_no = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS;
430 bi->word_no = 0;
434 /* Advance to the next nonzero bit of an intersecting pair of
435 bitmaps. We will have already advanced past the just iterated bit.
436 Return true if there is a bit to iterate. */
438 static inline bool
439 bmp_iter_and (bitmap_iterator *bi, unsigned *bit_no)
441 /* If our current word is nonzero, it contains the bit we want. */
442 if (bi->bits)
444 next_bit:
445 while (!(bi->bits & 1))
447 bi->bits >>= 1;
448 *bit_no += 1;
450 return true;
453 /* Round up to the word boundary. We might have just iterated past
454 the end of the last word, hence the -1. It is not possible for
455 bit_no to point at the beginning of the now last word. */
456 *bit_no = ((*bit_no + BITMAP_WORD_BITS - 1)
457 / BITMAP_WORD_BITS * BITMAP_WORD_BITS);
458 bi->word_no++;
460 while (1)
462 /* Find the next nonzero word in this elt. */
463 while (bi->word_no != BITMAP_ELEMENT_WORDS)
465 bi->bits = bi->elt1->bits[bi->word_no] & bi->elt2->bits[bi->word_no];
466 if (bi->bits)
467 goto next_bit;
468 *bit_no += BITMAP_WORD_BITS;
469 bi->word_no++;
472 /* Advance to the next identical element. */
475 /* Advance elt1 while it is less than elt2. We always want
476 to advance one elt. */
479 bi->elt1 = bi->elt1->next;
480 if (!bi->elt1)
481 return false;
483 while (bi->elt1->indx < bi->elt2->indx);
485 /* Advance elt2 to be no less than elt1. This might not
486 advance. */
487 while (bi->elt2->indx < bi->elt1->indx)
489 bi->elt2 = bi->elt2->next;
490 if (!bi->elt2)
491 return false;
494 while (bi->elt1->indx != bi->elt2->indx);
496 *bit_no = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS;
497 bi->word_no = 0;
501 /* Advance to the next nonzero bit in the intersection of
502 complemented bitmaps. We will have already advanced past the just
503 iterated bit. */
505 static inline bool
506 bmp_iter_and_compl (bitmap_iterator *bi, unsigned *bit_no)
508 /* If our current word is nonzero, it contains the bit we want. */
509 if (bi->bits)
511 next_bit:
512 while (!(bi->bits & 1))
514 bi->bits >>= 1;
515 *bit_no += 1;
517 return true;
520 /* Round up to the word boundary. We might have just iterated past
521 the end of the last word, hence the -1. It is not possible for
522 bit_no to point at the beginning of the now last word. */
523 *bit_no = ((*bit_no + BITMAP_WORD_BITS - 1)
524 / BITMAP_WORD_BITS * BITMAP_WORD_BITS);
525 bi->word_no++;
527 while (1)
529 /* Find the next nonzero word in this elt. */
530 while (bi->word_no != BITMAP_ELEMENT_WORDS)
532 bi->bits = bi->elt1->bits[bi->word_no];
533 if (bi->elt2 && bi->elt2->indx == bi->elt1->indx)
534 bi->bits &= ~bi->elt2->bits[bi->word_no];
535 if (bi->bits)
536 goto next_bit;
537 *bit_no += BITMAP_WORD_BITS;
538 bi->word_no++;
541 /* Advance to the next element of elt1. */
542 bi->elt1 = bi->elt1->next;
543 if (!bi->elt1)
544 return false;
546 /* Advance elt2 until it is no less than elt1. */
547 while (bi->elt2 && bi->elt2->indx < bi->elt1->indx)
548 bi->elt2 = bi->elt2->next;
550 *bit_no = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS;
551 bi->word_no = 0;
555 /* Loop over all bits set in BITMAP, starting with MIN and setting
556 BITNUM to the bit number. ITER is a bitmap iterator. BITNUM
557 should be treated as a read-only variable as it contains loop
558 state. */
560 #define EXECUTE_IF_SET_IN_BITMAP(BITMAP, MIN, BITNUM, ITER) \
561 for (bmp_iter_set_init (&(ITER), (BITMAP), (MIN), &(BITNUM)); \
562 bmp_iter_set (&(ITER), &(BITNUM)); \
563 bmp_iter_next (&(ITER), &(BITNUM)))
565 /* Loop over all the bits set in BITMAP1 & BITMAP2, starting with MIN
566 and setting BITNUM to the bit number. ITER is a bitmap iterator.
567 BITNUM should be treated as a read-only variable as it contains
568 loop state. */
570 #define EXECUTE_IF_AND_IN_BITMAP(BITMAP1, BITMAP2, MIN, BITNUM, ITER) \
571 for (bmp_iter_and_init (&(ITER), (BITMAP1), (BITMAP2), (MIN), \
572 &(BITNUM)); \
573 bmp_iter_and (&(ITER), &(BITNUM)); \
574 bmp_iter_next (&(ITER), &(BITNUM)))
576 /* Loop over all the bits set in BITMAP1 & ~BITMAP2, starting with MIN
577 and setting BITNUM to the bit number. ITER is a bitmap iterator.
578 BITNUM should be treated as a read-only variable as it contains
579 loop state. */
581 #define EXECUTE_IF_AND_COMPL_IN_BITMAP(BITMAP1, BITMAP2, MIN, BITNUM, ITER) \
582 for (bmp_iter_and_compl_init (&(ITER), (BITMAP1), (BITMAP2), (MIN), \
583 &(BITNUM)); \
584 bmp_iter_and_compl (&(ITER), &(BITNUM)); \
585 bmp_iter_next (&(ITER), &(BITNUM)))
587 #endif /* GCC_BITMAP_H */