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 /* Return nonzero if all bits in an element are zero. */
141 bitmap_element_zerop (element)
142 bitmap_element *element;
144 #if BITMAP_ELEMENT_WORDS == 2
145 return (element->bits[0] | element->bits[1]) == 0;
149 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
150 if (element->bits[i] != 0)
157 /* Link the bitmap element into the current bitmap linked list. */
160 bitmap_element_link (head, element)
162 bitmap_element *element;
164 unsigned int indx = element->indx;
167 /* If this is the first and only element, set it in. */
168 if (head->first == 0)
170 element->next = element->prev = 0;
171 head->first = element;
174 /* If this index is less than that of the current element, it goes someplace
175 before the current element. */
176 else if (indx < head->indx)
178 for (ptr = head->current;
179 ptr->prev != 0 && ptr->prev->indx > indx;
184 ptr->prev->next = element;
186 head->first = element;
188 element->prev = ptr->prev;
193 /* Otherwise, it must go someplace after the current element. */
196 for (ptr = head->current;
197 ptr->next != 0 && ptr->next->indx < indx;
202 ptr->next->prev = element;
204 element->next = ptr->next;
209 /* Set up so this is the first element searched. */
210 head->current = element;
214 /* Clear a bitmap by freeing the linked list. */
220 bitmap_element *element, *next;
222 for (element = head->first; element != 0; element = next)
224 next = element->next;
225 element->next = bitmap_free;
226 bitmap_free = element;
229 head->first = head->current = 0;
232 /* Copy a bitmap to another bitmap */
235 bitmap_copy (to, from)
239 bitmap_element *from_ptr, *to_ptr = 0;
240 #if BITMAP_ELEMENT_WORDS != 2
246 /* Copy elements in forward direction one at a time */
247 for (from_ptr = from->first; from_ptr; from_ptr = from_ptr->next)
249 bitmap_element *to_elt = bitmap_element_allocate ();
251 to_elt->indx = from_ptr->indx;
253 #if BITMAP_ELEMENT_WORDS == 2
254 to_elt->bits[0] = from_ptr->bits[0];
255 to_elt->bits[1] = from_ptr->bits[1];
257 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
258 to_elt->bits[i] = from_ptr->bits[i];
261 /* Here we have a special case of bitmap_element_link, for the case
262 where we know the links are being entered in sequence. */
265 to->first = to->current = to_elt;
266 to->indx = from_ptr->indx;
267 to_elt->next = to_elt->prev = 0;
271 to_elt->prev = to_ptr;
273 to_ptr->next = to_elt;
280 /* Find a bitmap element that would hold a bitmap's bit.
281 Update the `current' field even if we can't find an element that
282 would hold the bitmap's bit to make eventual allocation
285 static INLINE bitmap_element *
286 bitmap_find_bit (head, bit)
290 bitmap_element *element;
291 unsigned HOST_WIDE_INT indx = bit / BITMAP_ELEMENT_ALL_BITS;
293 if (head->current == 0)
296 if (head->indx > indx)
297 for (element = head->current;
298 element->prev != 0 && element->indx > indx;
299 element = element->prev)
303 for (element = head->current;
304 element->next != 0 && element->indx < indx;
305 element = element->next)
308 /* `element' is the nearest to the one we want. If it's not the one we
309 want, the one we want doesn't exist. */
310 head->current = element;
311 head->indx = element->indx;
312 if (element != 0 && element->indx != indx)
318 /* Clear a single bit in a bitmap. */
321 bitmap_clear_bit (head, bit)
325 bitmap_element *ptr = bitmap_find_bit (head, bit);
329 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
330 unsigned word_num = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT)
331 % BITMAP_ELEMENT_WORDS);
332 ptr->bits[word_num] &= ~ (((unsigned HOST_WIDE_INT) 1) << bit_num);
334 /* If we cleared the entire word, free up the element */
335 if (bitmap_element_zerop (ptr))
336 bitmap_element_free (head, ptr);
341 /* Set a single bit in a bitmap. */
344 bitmap_set_bit (head, bit)
348 bitmap_element *ptr = bitmap_find_bit (head, bit);
350 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
351 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
352 unsigned HOST_WIDE_INT bit_val = ((unsigned HOST_WIDE_INT) 1) << bit_num;
356 ptr = bitmap_element_allocate ();
357 ptr->indx = bit / BITMAP_ELEMENT_ALL_BITS;
358 ptr->bits[word_num] = bit_val;
359 bitmap_element_link (head, ptr);
362 ptr->bits[word_num] |= bit_val;
365 /* Return whether a bit is set within a bitmap. */
368 bitmap_bit_p (head, bit)
376 ptr = bitmap_find_bit (head, bit);
380 bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
382 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
384 return (ptr->bits[word_num] >> bit_num) & 1;
387 /* Store in bitmap TO the result of combining bitmap FROM1 and FROM2 using
388 a specific bit manipulation. Return true if TO changes. */
391 bitmap_operation (to, from1, from2, operation)
395 enum bitmap_bits operation;
397 #define HIGHEST_INDEX (unsigned int) ~0
399 bitmap_element *from1_ptr = from1->first;
400 bitmap_element *from2_ptr = from2->first;
401 unsigned int indx1 = (from1_ptr) ? from1_ptr->indx : HIGHEST_INDEX;
402 unsigned int indx2 = (from2_ptr) ? from2_ptr->indx : HIGHEST_INDEX;
403 bitmap_element *to_ptr = to->first;
404 bitmap_element *from1_tmp;
405 bitmap_element *from2_tmp;
406 bitmap_element *to_tmp;
410 #if BITMAP_ELEMENT_WORDS == 2
413 unsigned HOST_WIDE_INT t0, t1, f10, f11, f20, f21; \
414 f10 = from1_tmp->bits[0]; \
415 f20 = from2_tmp->bits[0]; \
417 changed |= (t0 != to_tmp->bits[0]); \
418 f11 = from1_tmp->bits[1]; \
419 f21 = from2_tmp->bits[1]; \
421 changed |= (t1 != to_tmp->bits[1]); \
422 to_tmp->bits[0] = t0; \
423 to_tmp->bits[1] = t1; \
428 unsigned HOST_WIDE_INT t, f1, f2; \
430 for (i = 0; i < BITMAP_ELEMENT_WORDS; ++i) \
432 f1 = from1_tmp->bits[i]; \
433 f2 = from2_tmp->bits[i]; \
435 changed |= (t != to_tmp->bits[i]); \
436 to_tmp->bits[i] = t; \
441 to->first = to->current = 0;
443 while (from1_ptr != 0 || from2_ptr != 0)
445 /* Figure out whether we need to substitute zero elements for
450 from1_tmp = from1_ptr;
451 from2_tmp = from2_ptr;
452 from1_ptr = from1_ptr->next;
453 indx1 = (from1_ptr) ? from1_ptr->indx : HIGHEST_INDEX;
454 from2_ptr = from2_ptr->next;
455 indx2 = (from2_ptr) ? from2_ptr->indx : HIGHEST_INDEX;
457 else if (indx1 < indx2)
460 from1_tmp = from1_ptr;
461 from2_tmp = &bitmap_zero;
462 from1_ptr = from1_ptr->next;
463 indx1 = (from1_ptr) ? from1_ptr->indx : HIGHEST_INDEX;
468 from1_tmp = &bitmap_zero;
469 from2_tmp = from2_ptr;
470 from2_ptr = from2_ptr->next;
471 indx2 = (from2_ptr) ? from2_ptr->indx : HIGHEST_INDEX;
474 /* Find the appropriate element from TO. Begin by discarding
475 elements that we've skipped. */
476 while (to_ptr && to_ptr->indx < indx)
480 to_ptr = to_ptr->next;
481 to_tmp->next = bitmap_free;
482 bitmap_free = to_tmp;
484 if (to_ptr && to_ptr->indx == indx)
487 to_ptr = to_ptr->next;
490 to_tmp = bitmap_element_allocate ();
492 /* Do the operation, and if any bits are set, link it into the
503 case BITMAP_AND_COMPL:
516 if (! bitmap_element_zerop (to_tmp))
519 bitmap_element_link (to, to_tmp);
523 to_tmp->next = bitmap_free;
524 bitmap_free = to_tmp;
528 /* If we have elements of TO left over, free the lot. */
532 for (to_tmp = to_ptr; to_tmp->next ; to_tmp = to_tmp->next)
534 to_tmp->next = bitmap_free;
535 bitmap_free = to_ptr;
543 /* Return true if two bitmaps are identical. */
546 bitmap_equal_p (a, b)
553 c.first = c.current = 0;
554 ret = ! bitmap_operation (&c, a, b, BITMAP_XOR);
560 /* Or into bitmap TO bitmap FROM1 and'ed with the complement of
564 bitmap_ior_and_compl (to, from1, from2)
571 tmp.first = tmp.current = 0;
573 bitmap_operation (&tmp, from1, from2, BITMAP_AND_COMPL);
574 bitmap_operation (to, to, &tmp, BITMAP_IOR);
578 /* Initialize a bitmap header. */
581 bitmap_initialize (head)
584 head->first = head->current = 0;
589 /* Debugging function to print out the contents of a bitmap. */
592 debug_bitmap_file (file, head)
598 fprintf (file, "\nfirst = ");
599 fprintf (file, HOST_PTR_PRINTF, (PTR) head->first);
600 fprintf (file, " current = ");
601 fprintf (file, HOST_PTR_PRINTF, (PTR) head->current);
602 fprintf (file, " indx = %u\n", head->indx);
604 for (ptr = head->first; ptr; ptr = ptr->next)
608 fprintf (file, "\t");
609 fprintf (file, HOST_PTR_PRINTF, (PTR) ptr);
610 fprintf (file, " next = ");
611 fprintf (file, HOST_PTR_PRINTF, (PTR) ptr->next);
612 fprintf (file, " prev = ");
613 fprintf (file, HOST_PTR_PRINTF, (PTR) ptr->prev);
614 fprintf (file, " indx = %u\n\t\tbits = {", ptr->indx);
616 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
617 for (j = 0; j < HOST_BITS_PER_WIDE_INT; j++)
618 if ((ptr->bits[i] >> j) & 1)
622 fprintf (file, "\n\t\t\t");
626 fprintf (file, " %u", (ptr->indx * BITMAP_ELEMENT_ALL_BITS
627 + i * HOST_BITS_PER_WIDE_INT + j));
631 fprintf (file, " }\n");
635 /* Function to be called from the debugger to print the contents
642 debug_bitmap_file (stdout, head);
645 /* Function to print out the contents of a bitmap. Unlike debug_bitmap_file,
646 it does not print anything but the bits. */
649 bitmap_print (file, head, prefix, suffix)
655 const char *comma = "";
658 fputs (prefix, file);
659 EXECUTE_IF_SET_IN_BITMAP (head, 0, i,
661 fprintf (file, "%s%d", comma, i);
664 fputs (suffix, file);
667 /* Release any memory allocated by bitmaps. */
670 bitmap_release_memory ()
673 if (bitmap_obstack_init)
675 bitmap_obstack_init = FALSE;
676 obstack_free (&bitmap_obstack, NULL_PTR);