1 /* Functions to support general ended bitmaps. 2 Copyright (C) 1997-2013 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify it under 7 the terms of the GNU General Public License as published by the Free 8 Software Foundation; either version 3, or (at your option) any later 9 version. 10 11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 #ifndef GCC_BITMAP_H 21 #define GCC_BITMAP_H 22 23 /* Implementation of sparse integer sets as a linked list. 24 25 This sparse set representation is suitable for sparse sets with an 26 unknown (a priori) universe. The set is represented as a double-linked 27 list of container nodes (struct bitmap_element_def). Each node consists 28 of an index for the first member that could be held in the container, 29 a small array of integers that represent the members in the container, 30 and pointers to the next and previous element in the linked list. The 31 elements in the list are sorted in ascending order, i.e. the head of 32 the list holds the element with the smallest member of the set. 33 34 For a given member I in the set: 35 - the element for I will have index is I / (bits per element) 36 - the position for I within element is I % (bits per element) 37 38 This representation is very space-efficient for large sparse sets, and 39 the size of the set can be changed dynamically without much overhead. 40 An important parameter is the number of bits per element. In this 41 implementation, there are 128 bits per element. This results in a 42 high storage overhead *per element*, but a small overall overhead if 43 the set is very sparse. 44 45 The downside is that many operations are relatively slow because the 46 linked list has to be traversed to test membership (i.e. member_p/ 47 add_member/remove_member). To improve the performance of this set 48 representation, the last accessed element and its index are cached. 49 For membership tests on members close to recently accessed members, 50 the cached last element improves membership test to a constant-time 51 operation. 52 53 The following operations can always be performed in O(1) time: 54 55 * clear : bitmap_clear 56 * choose_one : (not implemented, but could be 57 implemented in constant time) 58 59 The following operations can be performed in O(E) time worst-case (with 60 E the number of elements in the linked list), but in O(1) time with a 61 suitable access patterns: 62 63 * member_p : bitmap_bit_p 64 * add_member : bitmap_set_bit 65 * remove_member : bitmap_clear_bit 66 67 The following operations can be performed in O(E) time: 68 69 * cardinality : bitmap_count_bits 70 * set_size : bitmap_last_set_bit (but this could 71 in constant time with a pointer to 72 the last element in the chain) 73 74 Additionally, the linked-list sparse set representation supports 75 enumeration of the members in O(E) time: 76 77 * forall : EXECUTE_IF_SET_IN_BITMAP 78 * set_copy : bitmap_copy 79 * set_intersection : bitmap_intersect_p / 80 bitmap_and / bitmap_and_into / 81 EXECUTE_IF_AND_IN_BITMAP 82 * set_union : bitmap_ior / bitmap_ior_into 83 * set_difference : bitmap_intersect_compl_p / 84 bitmap_and_comp / bitmap_and_comp_into / 85 EXECUTE_IF_AND_COMPL_IN_BITMAP 86 * set_disjuction : bitmap_xor_comp / bitmap_xor_comp_into 87 * set_compare : bitmap_equal_p 88 89 Some operations on 3 sets that occur frequently in in data flow problems 90 are also implemented: 91 92 * A | (B & C) : bitmap_ior_and_into 93 * A | (B & ~C) : bitmap_ior_and_compl / 94 bitmap_ior_and_compl_into 95 96 The storage requirements for linked-list sparse sets are O(E), with E->N 97 in the worst case (a sparse set with large distances between the values 98 of the set members). 99 100 The linked-list set representation works well for problems involving very 101 sparse sets. The canonical example in GCC is, of course, the "set of 102 sets" for some CFG-based data flow problems (liveness analysis, dominance 103 frontiers, etc.). 104 105 This representation also works well for data flow problems where the size 106 of the set may grow dynamically, but care must be taken that the member_p, 107 add_member, and remove_member operations occur with a suitable access 108 pattern. 109 110 For random-access sets with a known, relatively small universe size, the 111 SparseSet or simple bitmap representations may be more efficient than a 112 linked-list set. For random-access sets of unknown universe, a hash table 113 or a balanced binary tree representation is likely to be a more suitable 114 choice. 115 116 Traversing linked lists is usually cache-unfriendly, even with the last 117 accessed element cached. 118 119 Cache performance can be improved by keeping the elements in the set 120 grouped together in memory, using a dedicated obstack for a set (or group 121 of related sets). Elements allocated on obstacks are released to a 122 free-list and taken off the free list. If multiple sets are allocated on 123 the same obstack, elements freed from one set may be re-used for one of 124 the other sets. This usually helps avoid cache misses. 125 126 A single free-list is used for all sets allocated in GGC space. This is 127 bad for persistent sets, so persistent sets should be allocated on an 128 obstack whenever possible. */ 129 130 #include "hashtab.h" 131 #include "statistics.h" 132 #include "obstack.h" 133 134 /* Fundamental storage type for bitmap. */ 135 136 typedef unsigned long BITMAP_WORD; 137 /* BITMAP_WORD_BITS needs to be unsigned, but cannot contain casts as 138 it is used in preprocessor directives -- hence the 1u. */ 139 #define BITMAP_WORD_BITS (CHAR_BIT * SIZEOF_LONG * 1u) 140 141 /* Number of words to use for each element in the linked list. */ 142 143 #ifndef BITMAP_ELEMENT_WORDS 144 #define BITMAP_ELEMENT_WORDS ((128 + BITMAP_WORD_BITS - 1) / BITMAP_WORD_BITS) 145 #endif 146 147 /* Number of bits in each actual element of a bitmap. */ 148 149 #define BITMAP_ELEMENT_ALL_BITS (BITMAP_ELEMENT_WORDS * BITMAP_WORD_BITS) 150 151 /* Obstack for allocating bitmaps and elements from. */ 152 typedef struct GTY (()) bitmap_obstack { 153 struct bitmap_element_def *elements; 154 struct bitmap_head_def *heads; 155 struct obstack GTY ((skip)) obstack; 156 } bitmap_obstack; 157 158 /* Bitmap set element. We use a linked list to hold only the bits that 159 are set. This allows for use to grow the bitset dynamically without 160 having to realloc and copy a giant bit array. 161 162 The free list is implemented as a list of lists. There is one 163 outer list connected together by prev fields. Each element of that 164 outer is an inner list (that may consist only of the outer list 165 element) that are connected by the next fields. The prev pointer 166 is undefined for interior elements. This allows 167 bitmap_elt_clear_from to be implemented in unit time rather than 168 linear in the number of elements to be freed. */ 169 170 typedef struct GTY((chain_next ("%h.next"), chain_prev ("%h.prev"))) bitmap_element_def { 171 struct bitmap_element_def *next; /* Next element. */ 172 struct bitmap_element_def *prev; /* Previous element. */ 173 unsigned int indx; /* regno/BITMAP_ELEMENT_ALL_BITS. */ 174 BITMAP_WORD bits[BITMAP_ELEMENT_WORDS]; /* Bits that are set. */ 175 } bitmap_element; 176 177 /* Head of bitmap linked list. The 'current' member points to something 178 already pointed to by the chain started by first, so GTY((skip)) it. */ 179 180 typedef struct GTY(()) bitmap_head_def { 181 unsigned int indx; /* Index of last element looked at. */ 182 unsigned int descriptor_id; /* Unique identifier for the allocation 183 site of this bitmap, for detailed 184 statistics gathering. */ 185 bitmap_element *first; /* First element in linked list. */ 186 bitmap_element * GTY((skip(""))) current; /* Last element looked at. */ 187 bitmap_obstack *obstack; /* Obstack to allocate elements from. 188 If NULL, then use GGC allocation. */ 189 } bitmap_head; 190 191 /* Global data */ 192 extern bitmap_element bitmap_zero_bits; /* Zero bitmap element */ 193 extern bitmap_obstack bitmap_default_obstack; /* Default bitmap obstack */ 194 195 /* Clear a bitmap by freeing up the linked list. */ 196 extern void bitmap_clear (bitmap); 197 198 /* Copy a bitmap to another bitmap. */ 199 extern void bitmap_copy (bitmap, const_bitmap); 200 201 /* True if two bitmaps are identical. */ 202 extern bool bitmap_equal_p (const_bitmap, const_bitmap); 203 204 /* True if the bitmaps intersect (their AND is non-empty). */ 205 extern bool bitmap_intersect_p (const_bitmap, const_bitmap); 206 207 /* True if the complement of the second intersects the first (their 208 AND_COMPL is non-empty). */ 209 extern bool bitmap_intersect_compl_p (const_bitmap, const_bitmap); 210 211 /* True if MAP is an empty bitmap. */ 212 inline bool bitmap_empty_p (const_bitmap map) 213 { 214 return !map->first; 215 } 216 217 /* True if the bitmap has only a single bit set. */ 218 extern bool bitmap_single_bit_set_p (const_bitmap); 219 220 /* Count the number of bits set in the bitmap. */ 221 extern unsigned long bitmap_count_bits (const_bitmap); 222 223 /* Boolean operations on bitmaps. The _into variants are two operand 224 versions that modify the first source operand. The other variants 225 are three operand versions that to not destroy the source bitmaps. 226 The operations supported are &, & ~, |, ^. */ 227 extern void bitmap_and (bitmap, const_bitmap, const_bitmap); 228 extern bool bitmap_and_into (bitmap, const_bitmap); 229 extern bool bitmap_and_compl (bitmap, const_bitmap, const_bitmap); 230 extern bool bitmap_and_compl_into (bitmap, const_bitmap); 231 #define bitmap_compl_and(DST, A, B) bitmap_and_compl (DST, B, A) 232 extern void bitmap_compl_and_into (bitmap, const_bitmap); 233 extern void bitmap_clear_range (bitmap, unsigned int, unsigned int); 234 extern void bitmap_set_range (bitmap, unsigned int, unsigned int); 235 extern bool bitmap_ior (bitmap, const_bitmap, const_bitmap); 236 extern bool bitmap_ior_into (bitmap, const_bitmap); 237 extern void bitmap_xor (bitmap, const_bitmap, const_bitmap); 238 extern void bitmap_xor_into (bitmap, const_bitmap); 239 240 /* DST = A | (B & C). Return true if DST changes. */ 241 extern bool bitmap_ior_and_into (bitmap DST, const_bitmap B, const_bitmap C); 242 /* DST = A | (B & ~C). Return true if DST changes. */ 243 extern bool bitmap_ior_and_compl (bitmap DST, const_bitmap A, 244 const_bitmap B, const_bitmap C); 245 /* A |= (B & ~C). Return true if A changes. */ 246 extern bool bitmap_ior_and_compl_into (bitmap A, 247 const_bitmap B, const_bitmap C); 248 249 /* Clear a single bit in a bitmap. Return true if the bit changed. */ 250 extern bool bitmap_clear_bit (bitmap, int); 251 252 /* Set a single bit in a bitmap. Return true if the bit changed. */ 253 extern bool bitmap_set_bit (bitmap, int); 254 255 /* Return true if a register is set in a register set. */ 256 extern int bitmap_bit_p (bitmap, int); 257 258 /* Debug functions to print a bitmap linked list. */ 259 extern void debug_bitmap (const_bitmap); 260 extern void debug_bitmap_file (FILE *, const_bitmap); 261 262 /* Print a bitmap. */ 263 extern void bitmap_print (FILE *, const_bitmap, const char *, const char *); 264 265 /* Initialize and release a bitmap obstack. */ 266 extern void bitmap_obstack_initialize (bitmap_obstack *); 267 extern void bitmap_obstack_release (bitmap_obstack *); 268 extern void bitmap_register (bitmap MEM_STAT_DECL); 269 extern void dump_bitmap_statistics (void); 270 271 /* Initialize a bitmap header. OBSTACK indicates the bitmap obstack 272 to allocate from, NULL for GC'd bitmap. */ 273 274 static inline void 275 bitmap_initialize_stat (bitmap head, bitmap_obstack *obstack MEM_STAT_DECL) 276 { 277 head->first = head->current = NULL; 278 head->obstack = obstack; 279 if (GATHER_STATISTICS) 280 bitmap_register (head PASS_MEM_STAT); 281 } 282 #define bitmap_initialize(h,o) bitmap_initialize_stat (h,o MEM_STAT_INFO) 283 284 /* Allocate and free bitmaps from obstack, malloc and gc'd memory. */ 285 extern bitmap bitmap_obstack_alloc_stat (bitmap_obstack *obstack MEM_STAT_DECL); 286 #define bitmap_obstack_alloc(t) bitmap_obstack_alloc_stat (t MEM_STAT_INFO) 287 extern bitmap bitmap_gc_alloc_stat (ALONE_MEM_STAT_DECL); 288 #define bitmap_gc_alloc() bitmap_gc_alloc_stat (ALONE_MEM_STAT_INFO) 289 extern void bitmap_obstack_free (bitmap); 290 291 /* A few compatibility/functions macros for compatibility with sbitmaps */ 292 inline void dump_bitmap (FILE *file, const_bitmap map) 293 { 294 bitmap_print (file, map, "", "\n"); 295 } 296 297 extern unsigned bitmap_first_set_bit (const_bitmap); 298 extern unsigned bitmap_last_set_bit (const_bitmap); 299 300 /* Compute bitmap hash (for purposes of hashing etc.) */ 301 extern hashval_t bitmap_hash(const_bitmap); 302 303 /* Allocate a bitmap from a bit obstack. */ 304 #define BITMAP_ALLOC(OBSTACK) bitmap_obstack_alloc (OBSTACK) 305 306 /* Allocate a gc'd bitmap. */ 307 #define BITMAP_GGC_ALLOC() bitmap_gc_alloc () 308 309 /* Do any cleanup needed on a bitmap when it is no longer used. */ 310 #define BITMAP_FREE(BITMAP) \ 311 ((void) (bitmap_obstack_free ((bitmap) BITMAP), (BITMAP) = (bitmap) NULL)) 312 313 /* Iterator for bitmaps. */ 314 315 typedef struct 316 { 317 /* Pointer to the current bitmap element. */ 318 bitmap_element *elt1; 319 320 /* Pointer to 2nd bitmap element when two are involved. */ 321 bitmap_element *elt2; 322 323 /* Word within the current element. */ 324 unsigned word_no; 325 326 /* Contents of the actually processed word. When finding next bit 327 it is shifted right, so that the actual bit is always the least 328 significant bit of ACTUAL. */ 329 BITMAP_WORD bits; 330 } bitmap_iterator; 331 332 /* Initialize a single bitmap iterator. START_BIT is the first bit to 333 iterate from. */ 334 335 static inline void 336 bmp_iter_set_init (bitmap_iterator *bi, const_bitmap map, 337 unsigned start_bit, unsigned *bit_no) 338 { 339 bi->elt1 = map->first; 340 bi->elt2 = NULL; 341 342 /* Advance elt1 until it is not before the block containing start_bit. */ 343 while (1) 344 { 345 if (!bi->elt1) 346 { 347 bi->elt1 = &bitmap_zero_bits; 348 break; 349 } 350 351 if (bi->elt1->indx >= start_bit / BITMAP_ELEMENT_ALL_BITS) 352 break; 353 bi->elt1 = bi->elt1->next; 354 } 355 356 /* We might have gone past the start bit, so reinitialize it. */ 357 if (bi->elt1->indx != start_bit / BITMAP_ELEMENT_ALL_BITS) 358 start_bit = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; 359 360 /* Initialize for what is now start_bit. */ 361 bi->word_no = start_bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS; 362 bi->bits = bi->elt1->bits[bi->word_no]; 363 bi->bits >>= start_bit % BITMAP_WORD_BITS; 364 365 /* If this word is zero, we must make sure we're not pointing at the 366 first bit, otherwise our incrementing to the next word boundary 367 will fail. It won't matter if this increment moves us into the 368 next word. */ 369 start_bit += !bi->bits; 370 371 *bit_no = start_bit; 372 } 373 374 /* Initialize an iterator to iterate over the intersection of two 375 bitmaps. START_BIT is the bit to commence from. */ 376 377 static inline void 378 bmp_iter_and_init (bitmap_iterator *bi, const_bitmap map1, const_bitmap map2, 379 unsigned start_bit, unsigned *bit_no) 380 { 381 bi->elt1 = map1->first; 382 bi->elt2 = map2->first; 383 384 /* Advance elt1 until it is not before the block containing 385 start_bit. */ 386 while (1) 387 { 388 if (!bi->elt1) 389 { 390 bi->elt2 = NULL; 391 break; 392 } 393 394 if (bi->elt1->indx >= start_bit / BITMAP_ELEMENT_ALL_BITS) 395 break; 396 bi->elt1 = bi->elt1->next; 397 } 398 399 /* Advance elt2 until it is not before elt1. */ 400 while (1) 401 { 402 if (!bi->elt2) 403 { 404 bi->elt1 = bi->elt2 = &bitmap_zero_bits; 405 break; 406 } 407 408 if (bi->elt2->indx >= bi->elt1->indx) 409 break; 410 bi->elt2 = bi->elt2->next; 411 } 412 413 /* If we're at the same index, then we have some intersecting bits. */ 414 if (bi->elt1->indx == bi->elt2->indx) 415 { 416 /* We might have advanced beyond the start_bit, so reinitialize 417 for that. */ 418 if (bi->elt1->indx != start_bit / BITMAP_ELEMENT_ALL_BITS) 419 start_bit = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; 420 421 bi->word_no = start_bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS; 422 bi->bits = bi->elt1->bits[bi->word_no] & bi->elt2->bits[bi->word_no]; 423 bi->bits >>= start_bit % BITMAP_WORD_BITS; 424 } 425 else 426 { 427 /* Otherwise we must immediately advance elt1, so initialize for 428 that. */ 429 bi->word_no = BITMAP_ELEMENT_WORDS - 1; 430 bi->bits = 0; 431 } 432 433 /* If this word is zero, we must make sure we're not pointing at the 434 first bit, otherwise our incrementing to the next word boundary 435 will fail. It won't matter if this increment moves us into the 436 next word. */ 437 start_bit += !bi->bits; 438 439 *bit_no = start_bit; 440 } 441 442 /* Initialize an iterator to iterate over the bits in MAP1 & ~MAP2. 443 */ 444 445 static inline void 446 bmp_iter_and_compl_init (bitmap_iterator *bi, 447 const_bitmap map1, const_bitmap map2, 448 unsigned start_bit, unsigned *bit_no) 449 { 450 bi->elt1 = map1->first; 451 bi->elt2 = map2->first; 452 453 /* Advance elt1 until it is not before the block containing start_bit. */ 454 while (1) 455 { 456 if (!bi->elt1) 457 { 458 bi->elt1 = &bitmap_zero_bits; 459 break; 460 } 461 462 if (bi->elt1->indx >= start_bit / BITMAP_ELEMENT_ALL_BITS) 463 break; 464 bi->elt1 = bi->elt1->next; 465 } 466 467 /* Advance elt2 until it is not before elt1. */ 468 while (bi->elt2 && bi->elt2->indx < bi->elt1->indx) 469 bi->elt2 = bi->elt2->next; 470 471 /* We might have advanced beyond the start_bit, so reinitialize for 472 that. */ 473 if (bi->elt1->indx != start_bit / BITMAP_ELEMENT_ALL_BITS) 474 start_bit = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; 475 476 bi->word_no = start_bit / BITMAP_WORD_BITS % BITMAP_ELEMENT_WORDS; 477 bi->bits = bi->elt1->bits[bi->word_no]; 478 if (bi->elt2 && bi->elt1->indx == bi->elt2->indx) 479 bi->bits &= ~bi->elt2->bits[bi->word_no]; 480 bi->bits >>= start_bit % BITMAP_WORD_BITS; 481 482 /* If this word is zero, we must make sure we're not pointing at the 483 first bit, otherwise our incrementing to the next word boundary 484 will fail. It won't matter if this increment moves us into the 485 next word. */ 486 start_bit += !bi->bits; 487 488 *bit_no = start_bit; 489 } 490 491 /* Advance to the next bit in BI. We don't advance to the next 492 nonzero bit yet. */ 493 494 static inline void 495 bmp_iter_next (bitmap_iterator *bi, unsigned *bit_no) 496 { 497 bi->bits >>= 1; 498 *bit_no += 1; 499 } 500 501 /* Advance to first set bit in BI. */ 502 503 static inline void 504 bmp_iter_next_bit (bitmap_iterator * bi, unsigned *bit_no) 505 { 506 #if (GCC_VERSION >= 3004) 507 { 508 unsigned int n = __builtin_ctzl (bi->bits); 509 gcc_assert (sizeof (unsigned long) == sizeof (BITMAP_WORD)); 510 bi->bits >>= n; 511 *bit_no += n; 512 } 513 #else 514 while (!(bi->bits & 1)) 515 { 516 bi->bits >>= 1; 517 *bit_no += 1; 518 } 519 #endif 520 } 521 522 /* Advance to the next nonzero bit of a single bitmap, we will have 523 already advanced past the just iterated bit. Return true if there 524 is a bit to iterate. */ 525 526 static inline bool 527 bmp_iter_set (bitmap_iterator *bi, unsigned *bit_no) 528 { 529 /* If our current word is nonzero, it contains the bit we want. */ 530 if (bi->bits) 531 { 532 next_bit: 533 bmp_iter_next_bit (bi, bit_no); 534 return true; 535 } 536 537 /* Round up to the word boundary. We might have just iterated past 538 the end of the last word, hence the -1. It is not possible for 539 bit_no to point at the beginning of the now last word. */ 540 *bit_no = ((*bit_no + BITMAP_WORD_BITS - 1) 541 / BITMAP_WORD_BITS * BITMAP_WORD_BITS); 542 bi->word_no++; 543 544 while (1) 545 { 546 /* Find the next nonzero word in this elt. */ 547 while (bi->word_no != BITMAP_ELEMENT_WORDS) 548 { 549 bi->bits = bi->elt1->bits[bi->word_no]; 550 if (bi->bits) 551 goto next_bit; 552 *bit_no += BITMAP_WORD_BITS; 553 bi->word_no++; 554 } 555 556 /* Advance to the next element. */ 557 bi->elt1 = bi->elt1->next; 558 if (!bi->elt1) 559 return false; 560 *bit_no = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; 561 bi->word_no = 0; 562 } 563 } 564 565 /* Advance to the next nonzero bit of an intersecting pair of 566 bitmaps. We will have already advanced past the just iterated bit. 567 Return true if there is a bit to iterate. */ 568 569 static inline bool 570 bmp_iter_and (bitmap_iterator *bi, unsigned *bit_no) 571 { 572 /* If our current word is nonzero, it contains the bit we want. */ 573 if (bi->bits) 574 { 575 next_bit: 576 bmp_iter_next_bit (bi, bit_no); 577 return true; 578 } 579 580 /* Round up to the word boundary. We might have just iterated past 581 the end of the last word, hence the -1. It is not possible for 582 bit_no to point at the beginning of the now last word. */ 583 *bit_no = ((*bit_no + BITMAP_WORD_BITS - 1) 584 / BITMAP_WORD_BITS * BITMAP_WORD_BITS); 585 bi->word_no++; 586 587 while (1) 588 { 589 /* Find the next nonzero word in this elt. */ 590 while (bi->word_no != BITMAP_ELEMENT_WORDS) 591 { 592 bi->bits = bi->elt1->bits[bi->word_no] & bi->elt2->bits[bi->word_no]; 593 if (bi->bits) 594 goto next_bit; 595 *bit_no += BITMAP_WORD_BITS; 596 bi->word_no++; 597 } 598 599 /* Advance to the next identical element. */ 600 do 601 { 602 /* Advance elt1 while it is less than elt2. We always want 603 to advance one elt. */ 604 do 605 { 606 bi->elt1 = bi->elt1->next; 607 if (!bi->elt1) 608 return false; 609 } 610 while (bi->elt1->indx < bi->elt2->indx); 611 612 /* Advance elt2 to be no less than elt1. This might not 613 advance. */ 614 while (bi->elt2->indx < bi->elt1->indx) 615 { 616 bi->elt2 = bi->elt2->next; 617 if (!bi->elt2) 618 return false; 619 } 620 } 621 while (bi->elt1->indx != bi->elt2->indx); 622 623 *bit_no = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; 624 bi->word_no = 0; 625 } 626 } 627 628 /* Advance to the next nonzero bit in the intersection of 629 complemented bitmaps. We will have already advanced past the just 630 iterated bit. */ 631 632 static inline bool 633 bmp_iter_and_compl (bitmap_iterator *bi, unsigned *bit_no) 634 { 635 /* If our current word is nonzero, it contains the bit we want. */ 636 if (bi->bits) 637 { 638 next_bit: 639 bmp_iter_next_bit (bi, bit_no); 640 return true; 641 } 642 643 /* Round up to the word boundary. We might have just iterated past 644 the end of the last word, hence the -1. It is not possible for 645 bit_no to point at the beginning of the now last word. */ 646 *bit_no = ((*bit_no + BITMAP_WORD_BITS - 1) 647 / BITMAP_WORD_BITS * BITMAP_WORD_BITS); 648 bi->word_no++; 649 650 while (1) 651 { 652 /* Find the next nonzero word in this elt. */ 653 while (bi->word_no != BITMAP_ELEMENT_WORDS) 654 { 655 bi->bits = bi->elt1->bits[bi->word_no]; 656 if (bi->elt2 && bi->elt2->indx == bi->elt1->indx) 657 bi->bits &= ~bi->elt2->bits[bi->word_no]; 658 if (bi->bits) 659 goto next_bit; 660 *bit_no += BITMAP_WORD_BITS; 661 bi->word_no++; 662 } 663 664 /* Advance to the next element of elt1. */ 665 bi->elt1 = bi->elt1->next; 666 if (!bi->elt1) 667 return false; 668 669 /* Advance elt2 until it is no less than elt1. */ 670 while (bi->elt2 && bi->elt2->indx < bi->elt1->indx) 671 bi->elt2 = bi->elt2->next; 672 673 *bit_no = bi->elt1->indx * BITMAP_ELEMENT_ALL_BITS; 674 bi->word_no = 0; 675 } 676 } 677 678 /* Loop over all bits set in BITMAP, starting with MIN and setting 679 BITNUM to the bit number. ITER is a bitmap iterator. BITNUM 680 should be treated as a read-only variable as it contains loop 681 state. */ 682 683 #ifndef EXECUTE_IF_SET_IN_BITMAP 684 /* See sbitmap.h for the other definition of EXECUTE_IF_SET_IN_BITMAP. */ 685 #define EXECUTE_IF_SET_IN_BITMAP(BITMAP, MIN, BITNUM, ITER) \ 686 for (bmp_iter_set_init (&(ITER), (BITMAP), (MIN), &(BITNUM)); \ 687 bmp_iter_set (&(ITER), &(BITNUM)); \ 688 bmp_iter_next (&(ITER), &(BITNUM))) 689 #endif 690 691 /* Loop over all the bits set in BITMAP1 & BITMAP2, starting with MIN 692 and setting BITNUM to the bit number. ITER is a bitmap iterator. 693 BITNUM should be treated as a read-only variable as it contains 694 loop state. */ 695 696 #define EXECUTE_IF_AND_IN_BITMAP(BITMAP1, BITMAP2, MIN, BITNUM, ITER) \ 697 for (bmp_iter_and_init (&(ITER), (BITMAP1), (BITMAP2), (MIN), \ 698 &(BITNUM)); \ 699 bmp_iter_and (&(ITER), &(BITNUM)); \ 700 bmp_iter_next (&(ITER), &(BITNUM))) 701 702 /* Loop over all the bits set in BITMAP1 & ~BITMAP2, starting with MIN 703 and setting BITNUM to the bit number. ITER is a bitmap iterator. 704 BITNUM should be treated as a read-only variable as it contains 705 loop state. */ 706 707 #define EXECUTE_IF_AND_COMPL_IN_BITMAP(BITMAP1, BITMAP2, MIN, BITNUM, ITER) \ 708 for (bmp_iter_and_compl_init (&(ITER), (BITMAP1), (BITMAP2), (MIN), \ 709 &(BITNUM)); \ 710 bmp_iter_and_compl (&(ITER), &(BITNUM)); \ 711 bmp_iter_next (&(ITER), &(BITNUM))) 712 713 #endif /* GCC_BITMAP_H */ 714
