1 /* Functions to support general ended bitmaps.
2 Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
28 /* Obstack to allocate bitmap elements from. */
29 static struct obstack bitmap_obstack;
30 static int bitmap_obstack_init = FALSE;
36 #define INLINE __inline__
41 bitmap_element bitmap_zero; /* An element of all zero bits. */
42 bitmap_element *bitmap_free; /* Freelist of bitmap elements. */
44 static void bitmap_element_free PARAMS ((bitmap, bitmap_element *));
45 static bitmap_element *bitmap_element_allocate PARAMS ((void));
46 static int bitmap_element_zerop PARAMS ((bitmap_element *));
47 static void bitmap_element_link PARAMS ((bitmap, bitmap_element *));
48 static bitmap_element *bitmap_find_bit PARAMS ((bitmap, unsigned int));
50 /* Free a bitmap element */
53 bitmap_element_free (head, elt)
57 bitmap_element *next = elt->next;
58 bitmap_element *prev = elt->prev;
66 if (head->first == elt)
69 /* Since the first thing we try is to insert before current,
70 make current the next entry in preference to the previous. */
71 if (head->current == elt)
72 head->current = next != 0 ? next : prev;
74 elt->next = bitmap_free;
78 /* Allocate a bitmap element. The bits are cleared, but nothing else is. */
80 static INLINE bitmap_element *
81 bitmap_element_allocate ()
83 bitmap_element *element;
84 #if BITMAP_ELEMENT_WORDS != 2
90 element = bitmap_free;
91 bitmap_free = element->next;
95 /* We can't use gcc_obstack_init to initialize the obstack since
96 print-rtl.c now calls bitmap functions, and bitmap is linked
97 into the gen* functions. */
98 if (!bitmap_obstack_init)
100 bitmap_obstack_init = TRUE;
102 /* Let particular systems override the size of a chunk. */
103 #ifndef OBSTACK_CHUNK_SIZE
104 #define OBSTACK_CHUNK_SIZE 0
106 /* Let them override the alloc and free routines too. */
107 #ifndef OBSTACK_CHUNK_ALLOC
108 #define OBSTACK_CHUNK_ALLOC xmalloc
110 #ifndef OBSTACK_CHUNK_FREE
111 #define OBSTACK_CHUNK_FREE free
114 #if !defined(__GNUC__) || (__GNUC__ < 2)
115 #define __alignof__(type) 0
118 obstack_specify_allocation (&bitmap_obstack, OBSTACK_CHUNK_SIZE,
119 __alignof__ (bitmap_element),
120 (void *(*) PARAMS ((long))) OBSTACK_CHUNK_ALLOC,
121 (void (*) PARAMS ((void *))) OBSTACK_CHUNK_FREE);
124 element = (bitmap_element *) obstack_alloc (&bitmap_obstack,
125 sizeof (bitmap_element));
128 #if BITMAP_ELEMENT_WORDS == 2
129 element->bits[0] = element->bits[1] = 0;
131 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
132 element->bits[i] = 0;
138 /* Release any memory allocated by bitmaps. */
141 bitmap_release_memory ()
144 if (bitmap_obstack_init)
146 bitmap_obstack_init = FALSE;
147 obstack_free (&bitmap_obstack, NULL);
151 /* Return nonzero if all bits in an element are zero. */
154 bitmap_element_zerop (element)
155 bitmap_element *element;
157 #if BITMAP_ELEMENT_WORDS == 2
158 return (element->bits[0] | element->bits[1]) == 0;
162 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
163 if (element->bits[i] != 0)
170 /* Link the bitmap element into the current bitmap linked list. */
173 bitmap_element_link (head, element)
175 bitmap_element *element;
177 unsigned int indx = element->indx;
180 /* If this is the first and only element, set it in. */
181 if (head->first == 0)
183 element->next = element->prev = 0;
184 head->first = element;
187 /* If this index is less than that of the current element, it goes someplace
188 before the current element. */
189 else if (indx < head->indx)
191 for (ptr = head->current;
192 ptr->prev != 0 && ptr->prev->indx > indx;
197 ptr->prev->next = element;
199 head->first = element;
201 element->prev = ptr->prev;
206 /* Otherwise, it must go someplace after the current element. */
209 for (ptr = head->current;
210 ptr->next != 0 && ptr->next->indx < indx;
215 ptr->next->prev = element;
217 element->next = ptr->next;
222 /* Set up so this is the first element searched. */
223 head->current = element;
227 /* Clear a bitmap by freeing the linked list. */
233 bitmap_element *element, *next;
235 for (element = head->first; element != 0; element = next)
237 next = element->next;
238 element->next = bitmap_free;
239 bitmap_free = element;
242 head->first = head->current = 0;
245 /* Copy a bitmap to another bitmap */
248 bitmap_copy (to, from)
252 bitmap_element *from_ptr, *to_ptr = 0;
253 #if BITMAP_ELEMENT_WORDS != 2
259 /* Copy elements in forward direction one at a time */
260 for (from_ptr = from->first; from_ptr; from_ptr = from_ptr->next)
262 bitmap_element *to_elt = bitmap_element_allocate ();
264 to_elt->indx = from_ptr->indx;
266 #if BITMAP_ELEMENT_WORDS == 2
267 to_elt->bits[0] = from_ptr->bits[0];
268 to_elt->bits[1] = from_ptr->bits[1];
270 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
271 to_elt->bits[i] = from_ptr->bits[i];
274 /* Here we have a special case of bitmap_element_link, for the case
275 where we know the links are being entered in sequence. */
278 to->first = to->current = to_elt;
279 to->indx = from_ptr->indx;
280 to_elt->next = to_elt->prev = 0;
284 to_elt->prev = to_ptr;
286 to_ptr->next = to_elt;
293 /* Find a bitmap element that would hold a bitmap's bit.
294 Update the `current' field even if we can't find an element that
295 would hold the bitmap's bit to make eventual allocation
298 static INLINE bitmap_element *
299 bitmap_find_bit (head, bit)
303 bitmap_element *element;
304 unsigned HOST_WIDE_INT indx = bit / BITMAP_ELEMENT_ALL_BITS;
306 if (head->current == 0)
309 if (head->indx > indx)
310 for (element = head->current;
311 element->prev != 0 && element->indx > indx;
312 element = element->prev)
316 for (element = head->current;
317 element->next != 0 && element->indx < indx;
318 element = element->next)
321 /* `element' is the nearest to the one we want. If it's not the one we
322 want, the one we want doesn't exist. */
323 head->current = element;
324 head->indx = element->indx;
325 if (element != 0 && element->indx != indx)
331 /* Clear a single bit in a bitmap. */
334 bitmap_clear_bit (head, bit)
338 bitmap_element *ptr = bitmap_find_bit (head, bit);
342 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
343 unsigned word_num = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT)
344 % BITMAP_ELEMENT_WORDS);
345 ptr->bits[word_num] &= ~ (((unsigned HOST_WIDE_INT) 1) << bit_num);
347 /* If we cleared the entire word, free up the element */
348 if (bitmap_element_zerop (ptr))
349 bitmap_element_free (head, ptr);
354 /* Set a single bit in a bitmap. */
357 bitmap_set_bit (head, bit)
361 bitmap_element *ptr = bitmap_find_bit (head, bit);
363 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
364 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
365 unsigned HOST_WIDE_INT bit_val = ((unsigned HOST_WIDE_INT) 1) << bit_num;
369 ptr = bitmap_element_allocate ();
370 ptr->indx = bit / BITMAP_ELEMENT_ALL_BITS;
371 ptr->bits[word_num] = bit_val;
372 bitmap_element_link (head, ptr);
375 ptr->bits[word_num] |= bit_val;
378 /* Return whether a bit is set within a bitmap. */
381 bitmap_bit_p (head, bit)
389 ptr = bitmap_find_bit (head, bit);
393 bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
395 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
397 return (ptr->bits[word_num] >> bit_num) & 1;
402 bitmap_first_set_bit (a)
405 bitmap_element *ptr = a->first;
406 unsigned HOST_WIDE_INT word;
407 unsigned word_num, bit_num;
412 #if BITMAP_ELEMENT_WORDS == 2
413 word_num = 0, word = ptr->bits[0];
415 word_num = 1, word = ptr->bits[1];
417 for (word_num = 0; word_num < BITMAP_ELEMENT_WORDS; ++word_num)
418 if ((word = ptr->bits[word_num]) != 0)
422 /* Binary search for the first set bit. */
423 /* ??? It'd be nice to know if ffs or ffsl was available. */
428 #if HOST_BITS_PER_WIDE_INT > 64
429 #error "Fill out the table."
431 #if HOST_BITS_PER_WIDE_INT > 32
432 if ((word & 0xffffffff) == 0)
433 word >>= 32, bit_num += 32;
435 if ((word & 0xffff) == 0)
436 word >>= 16, bit_num += 16;
437 if ((word & 0xff) == 0)
438 word >>= 8, bit_num += 8;
446 return (ptr->indx * BITMAP_ELEMENT_ALL_BITS
447 + word_num * HOST_BITS_PER_WIDE_INT
452 bitmap_last_set_bit (a)
455 bitmap_element *ptr = a->first;
456 unsigned HOST_WIDE_INT word;
457 unsigned word_num, bit_num;
462 while (ptr->next != NULL)
465 #if BITMAP_ELEMENT_WORDS == 2
466 word_num = 1, word = ptr->bits[1];
468 word_num = 0, word = ptr->bits[0];
470 for (word_num = BITMAP_ELEMENT_WORDS; word_num-- > 0; )
471 if ((word = ptr->bits[word_num]) != 0)
475 /* Binary search for the last set bit. */
478 #if HOST_BITS_PER_WIDE_INT > 64
479 #error "Fill out the table."
481 #if HOST_BITS_PER_WIDE_INT > 32
482 if (word & ~ (unsigned HOST_WIDE_INT) 0xffffffff)
483 word >>= 32, bit_num += 32;
485 if (word & 0xffff0000)
486 word >>= 16, bit_num += 16;
488 word >>= 8, bit_num += 8;
490 word >>= 4, bit_num += 4;
492 word >>= 2, bit_num += 2;
494 word >>= 1, bit_num += 1;
496 return (ptr->indx * BITMAP_ELEMENT_ALL_BITS
497 + word_num * HOST_BITS_PER_WIDE_INT
501 /* Store in bitmap TO the result of combining bitmap FROM1 and FROM2 using
502 a specific bit manipulation. Return true if TO changes. */
505 bitmap_operation (to, from1, from2, operation)
509 enum bitmap_bits operation;
511 #define HIGHEST_INDEX (unsigned int) ~0
513 bitmap_element *from1_ptr = from1->first;
514 bitmap_element *from2_ptr = from2->first;
515 unsigned int indx1 = (from1_ptr) ? from1_ptr->indx : HIGHEST_INDEX;
516 unsigned int indx2 = (from2_ptr) ? from2_ptr->indx : HIGHEST_INDEX;
517 bitmap_element *to_ptr = to->first;
518 bitmap_element *from1_tmp;
519 bitmap_element *from2_tmp;
520 bitmap_element *to_tmp;
524 #if BITMAP_ELEMENT_WORDS == 2
527 unsigned HOST_WIDE_INT t0, t1, f10, f11, f20, f21; \
528 f10 = from1_tmp->bits[0]; \
529 f20 = from2_tmp->bits[0]; \
531 changed |= (t0 != to_tmp->bits[0]); \
532 f11 = from1_tmp->bits[1]; \
533 f21 = from2_tmp->bits[1]; \
535 changed |= (t1 != to_tmp->bits[1]); \
536 to_tmp->bits[0] = t0; \
537 to_tmp->bits[1] = t1; \
542 unsigned HOST_WIDE_INT t, f1, f2; \
544 for (i = 0; i < BITMAP_ELEMENT_WORDS; ++i) \
546 f1 = from1_tmp->bits[i]; \
547 f2 = from2_tmp->bits[i]; \
549 changed |= (t != to_tmp->bits[i]); \
550 to_tmp->bits[i] = t; \
555 to->first = to->current = 0;
557 while (from1_ptr != 0 || from2_ptr != 0)
559 /* Figure out whether we need to substitute zero elements for
564 from1_tmp = from1_ptr;
565 from2_tmp = from2_ptr;
566 from1_ptr = from1_ptr->next;
567 indx1 = (from1_ptr) ? from1_ptr->indx : HIGHEST_INDEX;
568 from2_ptr = from2_ptr->next;
569 indx2 = (from2_ptr) ? from2_ptr->indx : HIGHEST_INDEX;
571 else if (indx1 < indx2)
574 from1_tmp = from1_ptr;
575 from2_tmp = &bitmap_zero;
576 from1_ptr = from1_ptr->next;
577 indx1 = (from1_ptr) ? from1_ptr->indx : HIGHEST_INDEX;
582 from1_tmp = &bitmap_zero;
583 from2_tmp = from2_ptr;
584 from2_ptr = from2_ptr->next;
585 indx2 = (from2_ptr) ? from2_ptr->indx : HIGHEST_INDEX;
588 /* Find the appropriate element from TO. Begin by discarding
589 elements that we've skipped. */
590 while (to_ptr && to_ptr->indx < indx)
594 to_ptr = to_ptr->next;
595 to_tmp->next = bitmap_free;
596 bitmap_free = to_tmp;
598 if (to_ptr && to_ptr->indx == indx)
601 to_ptr = to_ptr->next;
604 to_tmp = bitmap_element_allocate ();
606 /* Do the operation, and if any bits are set, link it into the
617 case BITMAP_AND_COMPL:
624 case BITMAP_IOR_COMPL:
632 if (! bitmap_element_zerop (to_tmp))
635 bitmap_element_link (to, to_tmp);
639 to_tmp->next = bitmap_free;
640 bitmap_free = to_tmp;
644 /* If we have elements of TO left over, free the lot. */
648 for (to_tmp = to_ptr; to_tmp->next ; to_tmp = to_tmp->next)
650 to_tmp->next = bitmap_free;
651 bitmap_free = to_ptr;
659 /* Return true if two bitmaps are identical. */
662 bitmap_equal_p (a, b)
669 c.first = c.current = 0;
670 ret = ! bitmap_operation (&c, a, b, BITMAP_XOR);
676 /* Or into bitmap TO bitmap FROM1 and'ed with the complement of
680 bitmap_ior_and_compl (to, from1, from2)
687 tmp.first = tmp.current = 0;
689 bitmap_operation (&tmp, from1, from2, BITMAP_AND_COMPL);
690 bitmap_operation (to, to, &tmp, BITMAP_IOR);
695 bitmap_union_of_diff (dst, a, b, c)
704 tmp.first = tmp.current = 0;
706 bitmap_operation (&tmp, b, c, BITMAP_AND_COMPL);
707 changed = bitmap_operation (dst, &tmp, a, BITMAP_IOR);
713 /* Initialize a bitmap header. */
716 bitmap_initialize (head)
719 head->first = head->current = 0;
724 /* Debugging function to print out the contents of a bitmap. */
727 debug_bitmap_file (file, head)
733 fprintf (file, "\nfirst = ");
734 fprintf (file, HOST_PTR_PRINTF, (PTR) head->first);
735 fprintf (file, " current = ");
736 fprintf (file, HOST_PTR_PRINTF, (PTR) head->current);
737 fprintf (file, " indx = %u\n", head->indx);
739 for (ptr = head->first; ptr; ptr = ptr->next)
743 fprintf (file, "\t");
744 fprintf (file, HOST_PTR_PRINTF, (PTR) ptr);
745 fprintf (file, " next = ");
746 fprintf (file, HOST_PTR_PRINTF, (PTR) ptr->next);
747 fprintf (file, " prev = ");
748 fprintf (file, HOST_PTR_PRINTF, (PTR) ptr->prev);
749 fprintf (file, " indx = %u\n\t\tbits = {", ptr->indx);
751 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
752 for (j = 0; j < HOST_BITS_PER_WIDE_INT; j++)
753 if ((ptr->bits[i] >> j) & 1)
757 fprintf (file, "\n\t\t\t");
761 fprintf (file, " %u", (ptr->indx * BITMAP_ELEMENT_ALL_BITS
762 + i * HOST_BITS_PER_WIDE_INT + j));
766 fprintf (file, " }\n");
770 /* Function to be called from the debugger to print the contents
777 debug_bitmap_file (stdout, head);
780 /* Function to print out the contents of a bitmap. Unlike debug_bitmap_file,
781 it does not print anything but the bits. */
784 bitmap_print (file, head, prefix, suffix)
790 const char *comma = "";
793 fputs (prefix, file);
794 EXECUTE_IF_SET_IN_BITMAP (head, 0, i,
796 fprintf (file, "%s%d", comma, i);
799 fputs (suffix, file);