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. */
27 #include "basic-block.h"
29 /* Obstack to allocate bitmap elements from. */
30 static struct obstack bitmap_obstack;
31 static int bitmap_obstack_init = FALSE;
37 #define INLINE __inline__
42 bitmap_element bitmap_zero; /* An element of all zero bits. */
43 bitmap_element *bitmap_free; /* Freelist of bitmap elements. */
45 static void bitmap_element_free PARAMS ((bitmap, bitmap_element *));
46 static bitmap_element *bitmap_element_allocate PARAMS ((void));
47 static int bitmap_element_zerop PARAMS ((bitmap_element *));
48 static void bitmap_element_link PARAMS ((bitmap, bitmap_element *));
49 static bitmap_element *bitmap_find_bit PARAMS ((bitmap, unsigned int));
51 /* Free a bitmap element */
54 bitmap_element_free (head, elt)
58 bitmap_element *next = elt->next;
59 bitmap_element *prev = elt->prev;
67 if (head->first == elt)
70 /* Since the first thing we try is to insert before current,
71 make current the next entry in preference to the previous. */
72 if (head->current == elt)
73 head->current = next != 0 ? next : prev;
75 elt->next = bitmap_free;
79 /* Allocate a bitmap element. The bits are cleared, but nothing else is. */
81 static INLINE bitmap_element *
82 bitmap_element_allocate ()
84 bitmap_element *element;
85 #if BITMAP_ELEMENT_WORDS != 2
91 element = bitmap_free;
92 bitmap_free = element->next;
96 /* We can't use gcc_obstack_init to initialize the obstack since
97 print-rtl.c now calls bitmap functions, and bitmap is linked
98 into the gen* functions. */
99 if (!bitmap_obstack_init)
101 bitmap_obstack_init = TRUE;
103 /* Let particular systems override the size of a chunk. */
104 #ifndef OBSTACK_CHUNK_SIZE
105 #define OBSTACK_CHUNK_SIZE 0
107 /* Let them override the alloc and free routines too. */
108 #ifndef OBSTACK_CHUNK_ALLOC
109 #define OBSTACK_CHUNK_ALLOC xmalloc
111 #ifndef OBSTACK_CHUNK_FREE
112 #define OBSTACK_CHUNK_FREE free
115 #if !defined(__GNUC__) || (__GNUC__ < 2)
116 #define __alignof__(type) 0
119 obstack_specify_allocation (&bitmap_obstack, OBSTACK_CHUNK_SIZE,
120 __alignof__ (bitmap_element),
121 (void *(*) PARAMS ((long))) OBSTACK_CHUNK_ALLOC,
122 (void (*) PARAMS ((void *))) OBSTACK_CHUNK_FREE);
125 element = (bitmap_element *) obstack_alloc (&bitmap_obstack,
126 sizeof (bitmap_element));
129 #if BITMAP_ELEMENT_WORDS == 2
130 element->bits[0] = element->bits[1] = 0;
132 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
133 element->bits[i] = 0;
139 /* Return nonzero if all bits in an element are zero. */
142 bitmap_element_zerop (element)
143 bitmap_element *element;
145 #if BITMAP_ELEMENT_WORDS == 2
146 return (element->bits[0] | element->bits[1]) == 0;
150 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
151 if (element->bits[i] != 0)
158 /* Link the bitmap element into the current bitmap linked list. */
161 bitmap_element_link (head, element)
163 bitmap_element *element;
165 unsigned int indx = element->indx;
168 /* If this is the first and only element, set it in. */
169 if (head->first == 0)
171 element->next = element->prev = 0;
172 head->first = element;
175 /* If this index is less than that of the current element, it goes someplace
176 before the current element. */
177 else if (indx < head->indx)
179 for (ptr = head->current;
180 ptr->prev != 0 && ptr->prev->indx > indx;
185 ptr->prev->next = element;
187 head->first = element;
189 element->prev = ptr->prev;
194 /* Otherwise, it must go someplace after the current element. */
197 for (ptr = head->current;
198 ptr->next != 0 && ptr->next->indx < indx;
203 ptr->next->prev = element;
205 element->next = ptr->next;
210 /* Set up so this is the first element searched. */
211 head->current = element;
215 /* Clear a bitmap by freeing the linked list. */
221 bitmap_element *element, *next;
223 for (element = head->first; element != 0; element = next)
225 next = element->next;
226 element->next = bitmap_free;
227 bitmap_free = element;
230 head->first = head->current = 0;
233 /* Copy a bitmap to another bitmap */
236 bitmap_copy (to, from)
240 bitmap_element *from_ptr, *to_ptr = 0;
241 #if BITMAP_ELEMENT_WORDS != 2
247 /* Copy elements in forward direction one at a time */
248 for (from_ptr = from->first; from_ptr; from_ptr = from_ptr->next)
250 bitmap_element *to_elt = bitmap_element_allocate ();
252 to_elt->indx = from_ptr->indx;
254 #if BITMAP_ELEMENT_WORDS == 2
255 to_elt->bits[0] = from_ptr->bits[0];
256 to_elt->bits[1] = from_ptr->bits[1];
258 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
259 to_elt->bits[i] = from_ptr->bits[i];
262 /* Here we have a special case of bitmap_element_link, for the case
263 where we know the links are being entered in sequence. */
266 to->first = to->current = to_elt;
267 to->indx = from_ptr->indx;
268 to_elt->next = to_elt->prev = 0;
272 to_elt->prev = to_ptr;
274 to_ptr->next = to_elt;
281 /* Find a bitmap element that would hold a bitmap's bit.
282 Update the `current' field even if we can't find an element that
283 would hold the bitmap's bit to make eventual allocation
286 static INLINE bitmap_element *
287 bitmap_find_bit (head, bit)
291 bitmap_element *element;
292 unsigned HOST_WIDE_INT indx = bit / BITMAP_ELEMENT_ALL_BITS;
294 if (head->current == 0)
297 if (head->indx > indx)
298 for (element = head->current;
299 element->prev != 0 && element->indx > indx;
300 element = element->prev)
304 for (element = head->current;
305 element->next != 0 && element->indx < indx;
306 element = element->next)
309 /* `element' is the nearest to the one we want. If it's not the one we
310 want, the one we want doesn't exist. */
311 head->current = element;
312 head->indx = element->indx;
313 if (element != 0 && element->indx != indx)
319 /* Clear a single bit in a bitmap. */
322 bitmap_clear_bit (head, bit)
326 bitmap_element *ptr = bitmap_find_bit (head, bit);
330 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
331 unsigned word_num = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT)
332 % BITMAP_ELEMENT_WORDS);
333 ptr->bits[word_num] &= ~ (((unsigned HOST_WIDE_INT) 1) << bit_num);
335 /* If we cleared the entire word, free up the element */
336 if (bitmap_element_zerop (ptr))
337 bitmap_element_free (head, ptr);
342 /* Set a single bit in a bitmap. */
345 bitmap_set_bit (head, bit)
349 bitmap_element *ptr = bitmap_find_bit (head, bit);
351 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
352 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
353 unsigned HOST_WIDE_INT bit_val = ((unsigned HOST_WIDE_INT) 1) << bit_num;
357 ptr = bitmap_element_allocate ();
358 ptr->indx = bit / BITMAP_ELEMENT_ALL_BITS;
359 ptr->bits[word_num] = bit_val;
360 bitmap_element_link (head, ptr);
363 ptr->bits[word_num] |= bit_val;
366 /* Return whether a bit is set within a bitmap. */
369 bitmap_bit_p (head, bit)
377 ptr = bitmap_find_bit (head, bit);
381 bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
383 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
385 return (ptr->bits[word_num] >> bit_num) & 1;
388 /* Store in bitmap TO the result of combining bitmap FROM1 and FROM2 using
389 a specific bit manipulation. Return true if TO changes. */
392 bitmap_operation (to, from1, from2, operation)
396 enum bitmap_bits operation;
398 bitmap_element *from1_ptr = from1->first;
399 bitmap_element *from2_ptr = from2->first;
400 unsigned int indx1 = (from1_ptr) ? from1_ptr->indx : -1;
401 unsigned int indx2 = (from2_ptr) ? from2_ptr->indx : -1;
402 bitmap_element *to_ptr = to->first;
403 bitmap_element *from1_tmp;
404 bitmap_element *from2_tmp;
405 bitmap_element *to_tmp;
409 #if BITMAP_ELEMENT_WORDS == 2
412 unsigned HOST_WIDE_INT t0, t1, f10, f11, f20, f21; \
413 f10 = from1_tmp->bits[0]; \
414 f20 = from2_tmp->bits[0]; \
416 changed |= (t0 != to_tmp->bits[0]); \
417 f11 = from1_tmp->bits[1]; \
418 f21 = from2_tmp->bits[1]; \
420 changed |= (t1 != to_tmp->bits[1]); \
421 to_tmp->bits[0] = t0; \
422 to_tmp->bits[1] = t1; \
427 unsigned HOST_WIDE_INT t, f1, f2; \
429 for (i = 0; i < BITMAP_ELEMENT_WORDS; ++i) \
431 f1 = from1_tmp->bits[i]; \
432 f2 = from2_tmp->bits[i]; \
434 changed |= (t != to_tmp->bits[i]); \
435 to_tmp->bits[i] = t; \
440 to->first = to->current = 0;
442 while (from1_ptr != 0 || from2_ptr != 0)
444 /* Figure out whether we need to substitute zero elements for
449 from1_tmp = from1_ptr;
450 from2_tmp = from2_ptr;
451 from1_ptr = from1_ptr->next;
452 indx1 = (from1_ptr) ? from1_ptr->indx : -1;
453 from2_ptr = from2_ptr->next;
454 indx2 = (from2_ptr) ? from2_ptr->indx : -1;
456 else if (indx1 < indx2)
459 from1_tmp = from1_ptr;
460 from2_tmp = &bitmap_zero;
461 from1_ptr = from1_ptr->next;
462 indx1 = (from1_ptr) ? from1_ptr->indx : -1;
467 from1_tmp = &bitmap_zero;
468 from2_tmp = from2_ptr;
469 from2_ptr = from2_ptr->next;
470 indx2 = (from2_ptr) ? from2_ptr->indx : -1;
473 /* Find the appropriate element from TO. Begin by discarding
474 elements that we've skipped. */
475 while (to_ptr && to_ptr->indx < indx)
479 to_ptr = to_ptr->next;
480 to_tmp = bitmap_free;
481 bitmap_free = to_tmp;
483 if (to_ptr && to_ptr->indx == indx)
486 to_ptr = to_ptr->next;
489 to_tmp = bitmap_element_allocate ();
491 /* Do the operation, and if any bits are set, link it into the
502 case BITMAP_AND_COMPL:
515 if (! bitmap_element_zerop (to_tmp))
518 bitmap_element_link (to, to_tmp);
522 /* If we have elements of TO left over, free the lot. */
526 for (to_tmp = to_ptr; to_tmp->next ; to_tmp = to_tmp->next)
528 to_tmp->next = bitmap_free;
529 bitmap_free = to_ptr;
537 /* Return true if two bitmaps are identical. */
540 bitmap_equal_p (a, b)
547 c.first = c.current = 0;
548 ret = ! bitmap_operation (&c, a, b, BITMAP_XOR);
554 /* Or into bitmap TO bitmap FROM1 and'ed with the complement of
558 bitmap_ior_and_compl (to, from1, from2)
565 tmp.first = tmp.current = 0;
567 bitmap_operation (&tmp, from1, from2, BITMAP_AND_COMPL);
568 bitmap_operation (to, to, &tmp, BITMAP_IOR);
572 /* Initialize a bitmap header. */
575 bitmap_initialize (head)
578 head->first = head->current = 0;
583 /* Debugging function to print out the contents of a bitmap. */
586 debug_bitmap_file (file, head)
592 fprintf (file, "\nfirst = ");
593 fprintf (file, HOST_PTR_PRINTF, head->first);
594 fprintf (file, " current = ");
595 fprintf (file, HOST_PTR_PRINTF, head->current);
596 fprintf (file, " indx = %u\n", head->indx);
598 for (ptr = head->first; ptr; ptr = ptr->next)
602 fprintf (file, "\t");
603 fprintf (file, HOST_PTR_PRINTF, ptr);
604 fprintf (file, " next = ");
605 fprintf (file, HOST_PTR_PRINTF, ptr->next);
606 fprintf (file, " prev = ");
607 fprintf (file, HOST_PTR_PRINTF, ptr->prev);
608 fprintf (file, " indx = %u\n\t\tbits = {", ptr->indx);
610 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
611 for (j = 0; j < HOST_BITS_PER_WIDE_INT; j++)
612 if ((ptr->bits[i] >> j) & 1)
616 fprintf (file, "\n\t\t\t");
620 fprintf (file, " %u", (ptr->indx * BITMAP_ELEMENT_ALL_BITS
621 + i * HOST_BITS_PER_WIDE_INT + j));
625 fprintf (file, " }\n");
629 /* Function to be called from the debugger to print the contents
636 debug_bitmap_file (stdout, head);
639 /* Function to print out the contents of a bitmap. Unlike debug_bitmap_file,
640 it does not print anything but the bits. */
643 bitmap_print (file, head, prefix, suffix)
649 const char *comma = "";
652 fputs (prefix, file);
653 EXECUTE_IF_SET_IN_BITMAP (head, 0, i,
655 fprintf (file, "%s%d", comma, i);
658 fputs (suffix, file);
661 /* Release any memory allocated by bitmaps. */
664 bitmap_release_memory ()
667 if (bitmap_obstack_init)
669 bitmap_obstack_init = FALSE;
670 obstack_free (&bitmap_obstack, NULL_PTR);