1 /* Functions to support general ended bitmaps.
2 Copyright (C) 1997 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;
38 #define INLINE __inline__
43 bitmap_element bitmap_zero; /* An element of all zero bits. */
44 bitmap_element *bitmap_free; /* Freelist of bitmap elements. */
46 static void bitmap_element_free PROTO((bitmap, bitmap_element *));
47 static bitmap_element *bitmap_element_allocate PROTO((bitmap));
48 static int bitmap_element_zerop PROTO((bitmap_element *));
49 static void bitmap_element_link PROTO((bitmap, bitmap_element *));
50 static bitmap_element *bitmap_find_bit PROTO((bitmap, unsigned int));
52 /* Free a bitmap element */
55 bitmap_element_free (head, elt)
59 bitmap_element *next = elt->next;
60 bitmap_element *prev = elt->prev;
68 if (head->first == elt)
71 /* Since the first thing we try is to insert before current,
72 make current the next entry in preference to the previous. */
73 if (head->current == elt)
74 head->current = next != 0 ? next : prev;
76 elt->next = bitmap_free;
80 /* Allocate a bitmap element. The bits are cleared, but nothing else is. */
82 static INLINE bitmap_element *
83 bitmap_element_allocate (head)
86 bitmap_element *element;
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 *(*) ()) OBSTACK_CHUNK_ALLOC,
122 (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;
245 /* Copy elements in forward direction one at a time */
246 for (from_ptr = from->first; from_ptr; from_ptr = from_ptr->next)
248 bitmap_element *to_elt = bitmap_element_allocate (to);
250 to_elt->indx = from_ptr->indx;
252 #if BITMAP_ELEMENT_WORDS == 2
253 to_elt->bits[0] = from_ptr->bits[0];
254 to_elt->bits[1] = from_ptr->bits[1];
256 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
257 to_elt->bits[i] = from_ptr->bits[i];
260 /* Here we have a special case of bitmap_element_link, for the case
261 where we know the links are being entered in sequence. */
264 to->first = to->current = to_elt;
265 to->indx = from_ptr->indx;
266 to_elt->next = to_elt->prev = 0;
270 to_elt->prev = to_ptr;
272 to_ptr->next = to_elt;
279 /* Find a bitmap element that would hold a bitmap's bit.
280 Update the `current' field even if we can't find an element that
281 would hold the bitmap's bit to make eventual allocation
284 static INLINE bitmap_element *
285 bitmap_find_bit (head, bit)
289 bitmap_element *element;
290 unsigned HOST_WIDE_INT indx = bit / BITMAP_ELEMENT_ALL_BITS;
292 if (head->current == 0)
295 if (head->indx > indx)
296 for (element = head->current;
297 element->prev != 0 && element->indx > indx;
298 element = element->prev)
302 for (element = head->current;
303 element->next != 0 && element->indx < indx;
304 element = element->next)
307 /* `element' is the nearest to the one we want. If it's not the one we
308 want, the one we want doesn't exist. */
309 head->current = element;
310 head->indx = element->indx;
311 if (element != 0 && element->indx != indx)
317 /* Clear a single bit in a bitmap. */
320 bitmap_clear_bit (head, bit)
324 bitmap_element *ptr = bitmap_find_bit (head, bit);
328 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
329 unsigned word_num = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT)
330 % BITMAP_ELEMENT_WORDS);
331 ptr->bits[word_num] &= ~ (((unsigned HOST_WIDE_INT) 1) << bit_num);
333 /* If we cleared the entire word, free up the element */
334 if (bitmap_element_zerop (ptr))
335 bitmap_element_free (head, ptr);
340 /* Set a single bit in a bitmap. */
343 bitmap_set_bit (head, bit)
347 bitmap_element *ptr = bitmap_find_bit (head, bit);
349 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
350 unsigned bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
351 unsigned HOST_WIDE_INT bit_val = ((unsigned HOST_WIDE_INT) 1) << bit_num;
355 ptr = bitmap_element_allocate (head);
356 ptr->indx = bit / BITMAP_ELEMENT_ALL_BITS;
357 ptr->bits[word_num] = bit_val;
358 bitmap_element_link (head, ptr);
361 ptr->bits[word_num] |= bit_val;
364 /* Return whether a bit is set within a bitmap. */
367 bitmap_bit_p (head, bit)
375 ptr = bitmap_find_bit (head, bit);
379 bit_num = bit % (unsigned) HOST_BITS_PER_WIDE_INT;
381 = ((bit / (unsigned) HOST_BITS_PER_WIDE_INT) % BITMAP_ELEMENT_WORDS);
384 (ptr->bits[word_num] & (((unsigned HOST_WIDE_INT) 1) << bit_num)) != 0;
387 /* Store in bitmap TO the result of combining bitmap FROM1 and
388 FROM2 using a specific bit manipulation. */
391 bitmap_operation (to, from1, from2, operation)
395 enum bitmap_bits operation;
397 bitmap_element *delete_list = 0;
398 bitmap_element *from1_ptr = from1->first;
399 bitmap_element *from2_ptr = from2->first;
401 = (from1_ptr) ? from1_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
403 = (from2_ptr) ? from2_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
404 bitmap_element *to_ptr = 0;
405 bitmap_element *from1_tmp;
406 bitmap_element *from2_tmp;
410 /* To simplify things, always create a new list. If the old list was one
411 of the inputs, free it later. Otherwise, free it now. */
412 if (to == from1 || to == from2)
414 delete_list = to->first;
415 to->first = to->current = 0;
420 while (from1_ptr != 0 || from2_ptr != 0)
422 /* Figure out whether we need to substitute zero elements for
427 from1_tmp = from1_ptr;
428 from2_tmp = from2_ptr;
429 from1_ptr = from1_ptr->next;
430 indx1 = (from1_ptr) ? from1_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
431 from2_ptr = from2_ptr->next;
432 indx2 = (from2_ptr) ? from2_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
434 else if (indx1 < indx2)
437 from1_tmp = from1_ptr;
438 from2_tmp = &bitmap_zero;
439 from1_ptr = from1_ptr->next;
440 indx1 = (from1_ptr) ? from1_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
445 from1_tmp = &bitmap_zero;
446 from2_tmp = from2_ptr;
447 from2_ptr = from2_ptr->next;
448 indx2 = (from2_ptr) ? from2_ptr->indx : ~ (unsigned HOST_WIDE_INT) 0;
452 to_ptr = bitmap_element_allocate (to);
454 /* Do the operation, and if any bits are set, link it into the
462 #if BITMAP_ELEMENT_WORDS == 2
463 to_ptr->bits[0] = from1_tmp->bits[0] & from2_tmp->bits[0];
464 to_ptr->bits[1] = from1_tmp->bits[1] & from2_tmp->bits[1];
466 for (i = BITMAP_ELEMENT_WORDS - 1; i >= 0; i--)
467 to_ptr->bits[i] = from1_tmp->bits[i] & from2_tmp->bits[i];
471 case BITMAP_AND_COMPL:
472 #if BITMAP_ELEMENT_WORDS == 2
473 to_ptr->bits[0] = from1_tmp->bits[0] & ~ from2_tmp->bits[0];
474 to_ptr->bits[1] = from1_tmp->bits[1] & ~ from2_tmp->bits[1];
476 for (i = BITMAP_ELEMENT_WORDS - 1; i >= 0; i--)
477 to_ptr->bits[i] = from1_tmp->bits[i] & ~ from2_tmp->bits[i];
482 #if BITMAP_ELEMENT_WORDS == 2
483 to_ptr->bits[0] = from1_tmp->bits[0] | from2_tmp->bits[0];
484 to_ptr->bits[1] = from1_tmp->bits[1] | from2_tmp->bits[1];
486 for (i = BITMAP_ELEMENT_WORDS - 1; i >= 0; i--)
487 to_ptr->bits[i] = from1_tmp->bits[i] | from2_tmp->bits[i];
492 if (! bitmap_element_zerop (to_ptr))
495 bitmap_element_link (to, to_ptr);
500 /* If we have an unallocated element due to the last element being 0,
501 release it back to the free pool. Don't bother calling
502 bitmap_element_free since it was never linked into a bitmap. */
505 to_ptr->next = bitmap_free;
506 bitmap_free = to_ptr;
509 /* If the output bitmap was one of the inputs, free up its
510 elements now that we're done. */
511 for (; delete_list != 0; delete_list = to_ptr)
513 to_ptr = delete_list->next;
514 delete_list->next = bitmap_free;
515 bitmap_free = delete_list;
519 /* Or into bitmap TO bitmap FROM1 and'ed with the complement of
523 bitmap_ior_and_compl (to, from1, from2)
530 tmp.first = tmp.current = 0;
532 bitmap_operation (&tmp, from1, from2, BITMAP_AND_COMPL);
533 bitmap_operation (to, to, &tmp, BITMAP_IOR);
537 /* Initialize a bitmap header. */
540 bitmap_initialize (head)
543 head->first = head->current = 0;
548 /* Debugging function to print out the contents of a bitmap. */
551 bitmap_debug_file (file, head)
557 fprintf (file, "\nfirst = ");
558 fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) head->first);
559 fprintf (file, " current = ");
560 fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) head->current);
561 fprintf (file, " indx = %u\n", head->indx);
563 for (ptr = head->first; ptr; ptr = ptr->next)
567 fprintf (file, "\t");
568 fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) ptr);
569 fprintf (file, " next = ");
570 fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) ptr->next);
571 fprintf (file, " prev = ");
572 fprintf (file, HOST_PTR_PRINTF, (HOST_WIDE_INT) ptr->prev);
573 fprintf (file, " indx = %u\n\t\tbits = {", ptr->indx);
575 for (i = 0; i < BITMAP_ELEMENT_WORDS; i++)
576 for (j = 0; j < HOST_BITS_PER_WIDE_INT; j++)
577 if ((ptr->bits[i] & (((unsigned HOST_WIDE_INT) 1) << j)) != 0)
581 fprintf (file, "\n\t\t\t");
585 fprintf (file, " %u", (ptr->indx * BITMAP_ELEMENT_ALL_BITS
586 + i * HOST_BITS_PER_WIDE_INT + j));
590 fprintf (file, " }\n");
594 /* Function to be called from the debugger to print the contents
601 bitmap_debug_file (stdout, head);
604 /* Function to print out the contents of a bitmap. Unlike bitmap_debug_file,
605 it does not print anything but the bits. */
608 bitmap_print (file, head, prefix, suffix)
617 fputs (prefix, file);
618 EXECUTE_IF_SET_IN_BITMAP (head, 0, i,
620 fprintf (file, "%s%d", comma, i);
623 fputs (suffix, file);
626 /* Release any memory allocated by bitmaps. */
629 bitmap_release_memory ()
632 if (bitmap_obstack_init)
634 bitmap_obstack_init = FALSE;
635 obstack_free (&bitmap_obstack, NULL_PTR);