1 /* Functions to support general ended bitmaps.
2 Copyright (C) 1997, 1998 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"
33 #ifdef NEED_DECLARATION_FREE
34 extern void free PROTO((void *));
37 /* Obstack to allocate bitmap elements from. */
38 static struct obstack bitmap_obstack;
39 static int bitmap_obstack_init = FALSE;
46 #define INLINE __inline__
51 bitmap_element bitmap_zero; /* An element of all zero bits. */
52 bitmap_element *bitmap_free; /* Freelist of bitmap elements. */
54 static void bitmap_element_free PROTO((bitmap, bitmap_element *));
55 static bitmap_element *bitmap_element_allocate PROTO(());
56 static int bitmap_element_zerop PROTO((bitmap_element *));
57 static void bitmap_element_link PROTO((bitmap, bitmap_element *));
58 static bitmap_element *bitmap_find_bit PROTO((bitmap, unsigned int));
60 /* Free a bitmap element */
63 bitmap_element_free (head, elt)
67 bitmap_element *next = elt->next;
68 bitmap_element *prev = elt->prev;
76 if (head->first == elt)
79 /* Since the first thing we try is to insert before current,
80 make current the next entry in preference to the previous. */
81 if (head->current == elt)
82 head->current = next != 0 ? next : prev;
84 elt->next = bitmap_free;
88 /* Allocate a bitmap element. The bits are cleared, but nothing else is. */
90 static INLINE bitmap_element *
91 bitmap_element_allocate ()
93 bitmap_element *element;
94 #if BITMAP_ELEMENT_WORDS != 2
100 element = bitmap_free;
101 bitmap_free = element->next;
105 /* We can't use gcc_obstack_init to initialize the obstack since
106 print-rtl.c now calls bitmap functions, and bitmap is linked
107 into the gen* functions. */
108 if (!bitmap_obstack_init)
110 bitmap_obstack_init = TRUE;
112 /* Let particular systems override the size of a chunk. */
113 #ifndef OBSTACK_CHUNK_SIZE
114 #define OBSTACK_CHUNK_SIZE 0
116 /* Let them override the alloc and free routines too. */
117 #ifndef OBSTACK_CHUNK_ALLOC
118 #define OBSTACK_CHUNK_ALLOC xmalloc
120 #ifndef OBSTACK_CHUNK_FREE
121 #define OBSTACK_CHUNK_FREE free
124 #if !defined(__GNUC__) || (__GNUC__ < 2)
125 #define __alignof__(type) 0
128 obstack_specify_allocation (&bitmap_obstack, OBSTACK_CHUNK_SIZE,
129 __alignof__ (bitmap_element),
130 (void *(*) ()) OBSTACK_CHUNK_ALLOC,
131 (void (*) ()) OBSTACK_CHUNK_FREE);
134 element = (bitmap_element *) obstack_alloc (&bitmap_obstack,
135 sizeof (bitmap_element));
138 #if BITMAP_ELEMENT_WORDS == 2
139 element->bits[0] = element->bits[1] = 0;
141 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
142 element->bits[i] = 0;
148 /* Return nonzero if all bits in an element are zero. */
151 bitmap_element_zerop (element)
152 bitmap_element *element;
154 #if BITMAP_ELEMENT_WORDS == 2
155 return (element->bits[0] | element->bits[1]) == 0;
159 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
160 if (element->bits[i] != 0)
167 /* Link the bitmap element into the current bitmap linked list. */
170 bitmap_element_link (head, element)
172 bitmap_element *element;
174 unsigned int indx = element->indx;
177 /* If this is the first and only element, set it in. */
178 if (head->first == 0)
180 element->next = element->prev = 0;
181 head->first = element;
184 /* If this index is less than that of the current element, it goes someplace
185 before the current element. */
186 else if (indx < head->indx)
188 for (ptr = head->current;
189 ptr->prev != 0 && ptr->prev->indx > indx;
194 ptr->prev->next = element;
196 head->first = element;
198 element->prev = ptr->prev;
203 /* Otherwise, it must go someplace after the current element. */
206 for (ptr = head->current;
207 ptr->next != 0 && ptr->next->indx < indx;
212 ptr->next->prev = element;
214 element->next = ptr->next;
219 /* Set up so this is the first element searched. */
220 head->current = element;
224 /* Clear a bitmap by freeing the linked list. */
230 bitmap_element *element, *next;
232 for (element = head->first; element != 0; element = next)
234 next = element->next;
235 element->next = bitmap_free;
236 bitmap_free = element;
239 head->first = head->current = 0;
242 /* Copy a bitmap to another bitmap */
245 bitmap_copy (to, from)
249 bitmap_element *from_ptr, *to_ptr = 0;
250 #if BITMAP_ELEMENT_WORDS != 2
256 /* Copy elements in forward direction one at a time */
257 for (from_ptr = from->first; from_ptr; from_ptr = from_ptr->next)
259 bitmap_element *to_elt = bitmap_element_allocate ();
261 to_elt->indx = from_ptr->indx;
263 #if BITMAP_ELEMENT_WORDS == 2
264 to_elt->bits[0] = from_ptr->bits[0];
265 to_elt->bits[1] = from_ptr->bits[1];
267 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
268 to_elt->bits[i] = from_ptr->bits[i];
271 /* Here we have a special case of bitmap_element_link, for the case
272 where we know the links are being entered in sequence. */
275 to->first = to->current = to_elt;
276 to->indx = from_ptr->indx;
277 to_elt->next = to_elt->prev = 0;
281 to_elt->prev = to_ptr;
283 to_ptr->next = to_elt;
290 /* Find a bitmap element that would hold a bitmap's bit.
291 Update the `current' field even if we can't find an element that
292 would hold the bitmap's bit to make eventual allocation
295 static INLINE bitmap_element *
296 bitmap_find_bit (head, bit)
300 bitmap_element *element;
301 unsigned HOST_WIDE_INT indx = bit / BITMAP_ELEMENT_ALL_BITS;
303 if (head->current == 0)
306 if (head->indx > indx)
307 for (element = head->current;
308 element->prev != 0 && element->indx > indx;
309 element = element->prev)
313 for (element = head->current;
314 element->next != 0 && element->indx < indx;
315 element = element->next)
318 /* `element' is the nearest to the one we want. If it's not the one we
319 want, the one we want doesn't exist. */
320 head->current = element;
321 head->indx = element->indx;
322 if (element != 0 && element->indx != indx)
328 /* Clear a single bit in a bitmap. */
331 bitmap_clear_bit (head, bit)
335 bitmap_element *ptr = bitmap_find_bit (head, bit);
339 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
340 unsigned word_num = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT)
341 % BITMAP_ELEMENT_WORDS);
342 ptr->bits[word_num] &= ~ (((unsigned HOST_WIDE_INT) 1) << bit_num);
344 /* If we cleared the entire word, free up the element */
345 if (bitmap_element_zerop (ptr))
346 bitmap_element_free (head, ptr);
351 /* Set a single bit in a bitmap. */
354 bitmap_set_bit (head, bit)
358 bitmap_element *ptr = bitmap_find_bit (head, bit);
360 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
361 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
362 unsigned HOST_WIDE_INT bit_val = ((unsigned HOST_WIDE_INT) 1) << bit_num;
366 ptr = bitmap_element_allocate ();
367 ptr->indx = bit / BITMAP_ELEMENT_ALL_BITS;
368 ptr->bits[word_num] = bit_val;
369 bitmap_element_link (head, ptr);
372 ptr->bits[word_num] |= bit_val;
375 /* Return whether a bit is set within a bitmap. */
378 bitmap_bit_p (head, bit)
386 ptr = bitmap_find_bit (head, bit);
390 bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
392 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
395 (ptr->bits[word_num] & (((unsigned HOST_WIDE_INT) 1) << bit_num)) != 0;
398 /* Store in bitmap TO the result of combining bitmap FROM1 and
399 FROM2 using a specific bit manipulation. */
402 bitmap_operation (to, from1, from2, operation)
406 enum bitmap_bits operation;
408 bitmap_element *delete_list = 0;
409 bitmap_element *from1_ptr = from1->first;
410 bitmap_element *from2_ptr = from2->first;
412 = (from1_ptr) ? from1_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
414 = (from2_ptr) ? from2_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
415 bitmap_element *to_ptr = 0;
416 bitmap_element *from1_tmp;
417 bitmap_element *from2_tmp;
419 #if BITMAP_ELEMENT_WORDS != 2
423 /* To simplify things, always create a new list. If the old list was one
424 of the inputs, free it later. Otherwise, free it now. */
425 if (to == from1 || to == from2)
427 delete_list = to->first;
428 to->first = to->current = 0;
433 while (from1_ptr != 0 || from2_ptr != 0)
435 /* Figure out whether we need to substitute zero elements for
440 from1_tmp = from1_ptr;
441 from2_tmp = from2_ptr;
442 from1_ptr = from1_ptr->next;
443 indx1 = (from1_ptr) ? from1_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
444 from2_ptr = from2_ptr->next;
445 indx2 = (from2_ptr) ? from2_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
447 else if (indx1 < indx2)
450 from1_tmp = from1_ptr;
451 from2_tmp = &bitmap_zero;
452 from1_ptr = from1_ptr->next;
453 indx1 = (from1_ptr) ? from1_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
458 from1_tmp = &bitmap_zero;
459 from2_tmp = from2_ptr;
460 from2_ptr = from2_ptr->next;
461 indx2 = (from2_ptr) ? from2_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
465 to_ptr = bitmap_element_allocate ();
467 /* Do the operation, and if any bits are set, link it into the
475 #if BITMAP_ELEMENT_WORDS == 2
476 to_ptr->bits[0] = from1_tmp->bits[0] & from2_tmp->bits[0];
477 to_ptr->bits[1] = from1_tmp->bits[1] & from2_tmp->bits[1];
479 for (i = BITMAP_ELEMENT_WORDS - 1; i >= 0; i--)
480 to_ptr->bits[i] = from1_tmp->bits[i] & from2_tmp->bits[i];
484 case BITMAP_AND_COMPL:
485 #if BITMAP_ELEMENT_WORDS == 2
486 to_ptr->bits[0] = from1_tmp->bits[0] & ~ from2_tmp->bits[0];
487 to_ptr->bits[1] = from1_tmp->bits[1] & ~ from2_tmp->bits[1];
489 for (i = BITMAP_ELEMENT_WORDS - 1; i >= 0; i--)
490 to_ptr->bits[i] = from1_tmp->bits[i] & ~ from2_tmp->bits[i];
495 #if BITMAP_ELEMENT_WORDS == 2
496 to_ptr->bits[0] = from1_tmp->bits[0] | from2_tmp->bits[0];
497 to_ptr->bits[1] = from1_tmp->bits[1] | from2_tmp->bits[1];
499 for (i = BITMAP_ELEMENT_WORDS - 1; i >= 0; i--)
500 to_ptr->bits[i] = from1_tmp->bits[i] | from2_tmp->bits[i];
505 if (! bitmap_element_zerop (to_ptr))
508 bitmap_element_link (to, to_ptr);
513 /* If we have an unallocated element due to the last element being 0,
514 release it back to the free pool. Don't bother calling
515 bitmap_element_free since it was never linked into a bitmap. */
518 to_ptr->next = bitmap_free;
519 bitmap_free = to_ptr;
522 /* If the output bitmap was one of the inputs, free up its
523 elements now that we're done. */
524 for (; delete_list != 0; delete_list = to_ptr)
526 to_ptr = delete_list->next;
527 delete_list->next = bitmap_free;
528 bitmap_free = delete_list;
532 /* Or into bitmap TO bitmap FROM1 and'ed with the complement of
536 bitmap_ior_and_compl (to, from1, from2)
543 tmp.first = tmp.current = 0;
545 bitmap_operation (&tmp, from1, from2, BITMAP_AND_COMPL);
546 bitmap_operation (to, to, &tmp, BITMAP_IOR);
550 /* Initialize a bitmap header. */
553 bitmap_initialize (head)
556 head->first = head->current = 0;
561 /* Debugging function to print out the contents of a bitmap. */
564 bitmap_debug_file (file, head)
570 fprintf (file, "\nfirst = ");
571 fprintf (file, HOST_PTR_PRINTF, head->first);
572 fprintf (file, " current = ");
573 fprintf (file, HOST_PTR_PRINTF, head->current);
574 fprintf (file, " indx = %u\n", head->indx);
576 for (ptr = head->first; ptr; ptr = ptr->next)
580 fprintf (file, "\t");
581 fprintf (file, HOST_PTR_PRINTF, ptr);
582 fprintf (file, " next = ");
583 fprintf (file, HOST_PTR_PRINTF, ptr->next);
584 fprintf (file, " prev = ");
585 fprintf (file, HOST_PTR_PRINTF, ptr->prev);
586 fprintf (file, " indx = %u\n\t\tbits = {", ptr->indx);
588 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
589 for (j = 0; j < HOST_BITS_PER_WIDE_INT; j++)
590 if ((ptr->bits[i] & (((unsigned HOST_WIDE_INT) 1) << j)) != 0)
594 fprintf (file, "\n\t\t\t");
598 fprintf (file, " %u", (ptr->indx * BITMAP_ELEMENT_ALL_BITS
599 + i * HOST_BITS_PER_WIDE_INT + j));
603 fprintf (file, " }\n");
607 /* Function to be called from the debugger to print the contents
614 bitmap_debug_file (stdout, head);
617 /* Function to print out the contents of a bitmap. Unlike bitmap_debug_file,
618 it does not print anything but the bits. */
621 bitmap_print (file, head, prefix, suffix)
630 fputs (prefix, file);
631 EXECUTE_IF_SET_IN_BITMAP (head, 0, i,
633 fprintf (file, "%s%d", comma, i);
636 fputs (suffix, file);
639 /* Release any memory allocated by bitmaps. */
642 bitmap_release_memory ()
645 if (bitmap_obstack_init)
647 bitmap_obstack_init = FALSE;
648 obstack_free (&bitmap_obstack, NULL_PTR);