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add isl_constraint_cmp_last_non_zero
[isl.git] / isl_constraint.c
blob14e87d45dfd1935c106db23155fb5dc5bce14179
1 /*
2 * Copyright 2008-2009 Katholieke Universiteit Leuven
3 * Copyright 2010 INRIA Saclay
4 *
5 * Use of this software is governed by the MIT license
6 *
7 * Written by Sven Verdoolaege, K.U.Leuven, Departement
8 * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
9 * and INRIA Saclay - Ile-de-France, Parc Club Orsay Universite,
10 * ZAC des vignes, 4 rue Jacques Monod, 91893 Orsay, France
11 */
12
13 #include <isl_map_private.h>
14 #include <isl_constraint_private.h>
15 #include <isl_space_private.h>
16 #include <isl_seq.h>
17 #include <isl_aff_private.h>
18 #include <isl_local_space_private.h>
19 #include <isl_val_private.h>
20 #include <isl_vec_private.h>
21 #include <isl/deprecated/constraint_int.h>
22
23 #undef BASE
24 #define BASE constraint
25
26 #include <isl_list_templ.c>
27
28 isl_ctx *isl_constraint_get_ctx(__isl_keep isl_constraint *c)
29 {
30 return c ? isl_local_space_get_ctx(c->ls) : NULL;
31 }
32
33 static unsigned n(struct isl_constraint *c, enum isl_dim_type type)
34 {
35 return isl_local_space_dim(c->ls, type);
36 }
37
38 static unsigned offset(struct isl_constraint *c, enum isl_dim_type type)
39 {
40 return isl_local_space_offset(c->ls, type);
41 }
42
43 static unsigned basic_map_offset(__isl_keep isl_basic_map *bmap,
44 enum isl_dim_type type)
45 {
46 return type == isl_dim_div ? 1 + isl_space_dim(bmap->dim, isl_dim_all)
47 : 1 + isl_space_offset(bmap->dim, type);
48 }
49
50 static unsigned basic_set_offset(struct isl_basic_set *bset,
51 enum isl_dim_type type)
52 {
53 isl_space *dim = bset->dim;
54 switch (type) {
55 case isl_dim_param: return 1;
56 case isl_dim_in: return 1 + dim->nparam;
57 case isl_dim_out: return 1 + dim->nparam + dim->n_in;
58 case isl_dim_div: return 1 + dim->nparam + dim->n_in + dim->n_out;
59 default: return 0;
60 }
61 }
62
63 __isl_give isl_constraint *isl_constraint_alloc_vec(int eq,
64 __isl_take isl_local_space *ls, __isl_take isl_vec *v)
65 {
66 isl_constraint *constraint;
67
68 if (!ls || !v)
69 goto error;
70
71 constraint = isl_alloc_type(isl_vec_get_ctx(v), isl_constraint);
72 if (!constraint)
73 goto error;
74
75 constraint->ref = 1;
76 constraint->eq = eq;
77 constraint->ls = ls;
78 constraint->v = v;
79
80 return constraint;
81 error:
82 isl_local_space_free(ls);
83 isl_vec_free(v);
84 return NULL;
85 }
86
87 __isl_give isl_constraint *isl_constraint_alloc(int eq,
88 __isl_take isl_local_space *ls)
89 {
90 isl_ctx *ctx;
91 isl_vec *v;
92
93 if (!ls)
94 return NULL;
95
96 ctx = isl_local_space_get_ctx(ls);
97 v = isl_vec_alloc(ctx, 1 + isl_local_space_dim(ls, isl_dim_all));
98 v = isl_vec_clr(v);
99 return isl_constraint_alloc_vec(eq, ls, v);
100 }
101
102 struct isl_constraint *isl_basic_map_constraint(struct isl_basic_map *bmap,
103 isl_int **line)
104 {
105 int eq;
106 isl_ctx *ctx;
107 isl_vec *v;
108 isl_local_space *ls = NULL;
109 isl_constraint *constraint;
110
111 if (!bmap || !line)
112 goto error;
113
114 eq = line >= bmap->eq;
115
116 ctx = isl_basic_map_get_ctx(bmap);
117 ls = isl_basic_map_get_local_space(bmap);
118 v = isl_vec_alloc(ctx, 1 + isl_local_space_dim(ls, isl_dim_all));
119 if (!v)
120 goto error;
121 isl_seq_cpy(v->el, line[0], v->size);
122 constraint = isl_constraint_alloc_vec(eq, ls, v);
123
124 isl_basic_map_free(bmap);
125 return constraint;
126 error:
127 isl_local_space_free(ls);
128 isl_basic_map_free(bmap);
129 return NULL;
130 }
131
132 struct isl_constraint *isl_basic_set_constraint(struct isl_basic_set *bset,
133 isl_int **line)
134 {
135 return isl_basic_map_constraint((struct isl_basic_map *)bset, line);
136 }
137
138 __isl_give isl_constraint *isl_equality_alloc(__isl_take isl_local_space *ls)
139 {
140 return isl_constraint_alloc(1, ls);
141 }
142
143 __isl_give isl_constraint *isl_inequality_alloc(__isl_take isl_local_space *ls)
144 {
145 return isl_constraint_alloc(0, ls);
146 }
147
148 struct isl_constraint *isl_constraint_dup(struct isl_constraint *c)
149 {
150 if (!c)
151 return NULL;
152
153 return isl_constraint_alloc_vec(c->eq, isl_local_space_copy(c->ls),
154 isl_vec_copy(c->v));
155 }
156
157 struct isl_constraint *isl_constraint_cow(struct isl_constraint *c)
158 {
159 if (!c)
160 return NULL;
161
162 if (c->ref == 1)
163 return c;
164 c->ref--;
165 return isl_constraint_dup(c);
166 }
167
168 struct isl_constraint *isl_constraint_copy(struct isl_constraint *constraint)
169 {
170 if (!constraint)
171 return NULL;
172
173 constraint->ref++;
174 return constraint;
175 }
176
177 __isl_null isl_constraint *isl_constraint_free(__isl_take isl_constraint *c)
178 {
179 if (!c)
180 return NULL;
181
182 if (--c->ref > 0)
183 return NULL;
184
185 isl_local_space_free(c->ls);
186 isl_vec_free(c->v);
187 free(c);
188
189 return NULL;
190 }
191
192 /* Return the number of constraints in "bmap", i.e., the
193 * number of times isl_basic_map_foreach_constraint will
194 * call the callback.
195 */
196 int isl_basic_map_n_constraint(__isl_keep isl_basic_map *bmap)
197 {
198 if (!bmap)
199 return -1;
200
201 return bmap->n_eq + bmap->n_ineq;
202 }
203
204 /* Return the number of constraints in "bset", i.e., the
205 * number of times isl_basic_set_foreach_constraint will
206 * call the callback.
207 */
208 int isl_basic_set_n_constraint(__isl_keep isl_basic_set *bset)
209 {
210 return isl_basic_map_n_constraint(bset);
211 }
212
213 int isl_basic_map_foreach_constraint(__isl_keep isl_basic_map *bmap,
214 int (*fn)(__isl_take isl_constraint *c, void *user), void *user)
215 {
216 int i;
217 struct isl_constraint *c;
218
219 if (!bmap)
220 return -1;
221
222 isl_assert(bmap->ctx, ISL_F_ISSET(bmap, ISL_BASIC_MAP_FINAL),
223 return -1);
224
225 for (i = 0; i < bmap->n_eq; ++i) {
226 c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
227 &bmap->eq[i]);
228 if (!c)
229 return -1;
230 if (fn(c, user) < 0)
231 return -1;
232 }
233
234 for (i = 0; i < bmap->n_ineq; ++i) {
235 c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
236 &bmap->ineq[i]);
237 if (!c)
238 return -1;
239 if (fn(c, user) < 0)
240 return -1;
241 }
242
243 return 0;
244 }
245
246 int isl_basic_set_foreach_constraint(__isl_keep isl_basic_set *bset,
247 int (*fn)(__isl_take isl_constraint *c, void *user), void *user)
248 {
249 return isl_basic_map_foreach_constraint((isl_basic_map *)bset, fn, user);
250 }
251
252 /* Add the constraint to the list that "user" points to, if it is not
253 * a div constraint.
254 */
255 static int collect_constraint(__isl_take isl_constraint *constraint,
256 void *user)
257 {
258 isl_constraint_list **list = user;
259
260 if (isl_constraint_is_div_constraint(constraint))
261 isl_constraint_free(constraint);
262 else
263 *list = isl_constraint_list_add(*list, constraint);
264
265 return 0;
266 }
267
268 /* Return a list of constraints that, when combined, are equivalent
269 * to "bmap". The input is required to have only known divs.
270 *
271 * There is no need to include the div constraints as they are
272 * implied by the div expressions.
273 */
274 __isl_give isl_constraint_list *isl_basic_map_get_constraint_list(
275 __isl_keep isl_basic_map *bmap)
276 {
277 int n;
278 int known;
279 isl_ctx *ctx;
280 isl_constraint_list *list;
281
282 known = isl_basic_map_divs_known(bmap);
283 if (known < 0)
284 return NULL;
285 ctx = isl_basic_map_get_ctx(bmap);
286 if (!known)
287 isl_die(ctx, isl_error_invalid,
288 "input involves unknown divs", return NULL);
289
290 n = isl_basic_map_n_constraint(bmap);
291 list = isl_constraint_list_alloc(ctx, n);
292 if (isl_basic_map_foreach_constraint(bmap,
293 &collect_constraint, &list) < 0)
294 list = isl_constraint_list_free(list);
295
296 return list;
297 }
298
299 /* Return a list of constraints that, when combined, are equivalent
300 * to "bset". The input is required to have only known divs.
301 */
302 __isl_give isl_constraint_list *isl_basic_set_get_constraint_list(
303 __isl_keep isl_basic_set *bset)
304 {
305 return isl_basic_map_get_constraint_list(bset);
306 }
307
308 int isl_constraint_is_equal(struct isl_constraint *constraint1,
309 struct isl_constraint *constraint2)
310 {
311 int equal;
312
313 if (!constraint1 || !constraint2)
314 return 0;
315 if (constraint1->eq != constraint2->eq)
316 return 0;
317 equal = isl_local_space_is_equal(constraint1->ls, constraint2->ls);
318 if (equal < 0 || !equal)
319 return equal;
320 return isl_vec_is_equal(constraint1->v, constraint2->v);
321 }
322
323 struct isl_basic_map *isl_basic_map_add_constraint(
324 struct isl_basic_map *bmap, struct isl_constraint *constraint)
325 {
326 isl_ctx *ctx;
327 isl_space *dim;
328 int equal_space;
329
330 if (!bmap || !constraint)
331 goto error;
332
333 ctx = isl_constraint_get_ctx(constraint);
334 dim = isl_constraint_get_space(constraint);
335 equal_space = isl_space_is_equal(bmap->dim, dim);
336 isl_space_free(dim);
337 isl_assert(ctx, equal_space, goto error);
338
339 bmap = isl_basic_map_intersect(bmap,
340 isl_basic_map_from_constraint(constraint));
341 return bmap;
342 error:
343 isl_basic_map_free(bmap);
344 isl_constraint_free(constraint);
345 return NULL;
346 }
347
348 struct isl_basic_set *isl_basic_set_add_constraint(
349 struct isl_basic_set *bset, struct isl_constraint *constraint)
350 {
351 return (struct isl_basic_set *)
352 isl_basic_map_add_constraint((struct isl_basic_map *)bset,
353 constraint);
354 }
355
356 __isl_give isl_map *isl_map_add_constraint(__isl_take isl_map *map,
357 __isl_take isl_constraint *constraint)
358 {
359 isl_basic_map *bmap;
360
361 bmap = isl_basic_map_from_constraint(constraint);
362 map = isl_map_intersect(map, isl_map_from_basic_map(bmap));
363
364 return map;
365 }
366
367 __isl_give isl_set *isl_set_add_constraint(__isl_take isl_set *set,
368 __isl_take isl_constraint *constraint)
369 {
370 return isl_map_add_constraint(set, constraint);
371 }
372
373 __isl_give isl_space *isl_constraint_get_space(
374 __isl_keep isl_constraint *constraint)
375 {
376 return constraint ? isl_local_space_get_space(constraint->ls) : NULL;
377 }
378
379 __isl_give isl_local_space *isl_constraint_get_local_space(
380 __isl_keep isl_constraint *constraint)
381 {
382 return constraint ? isl_local_space_copy(constraint->ls) : NULL;
383 }
384
385 int isl_constraint_dim(struct isl_constraint *constraint,
386 enum isl_dim_type type)
387 {
388 if (!constraint)
389 return -1;
390 return n(constraint, type);
391 }
392
393 int isl_constraint_involves_dims(__isl_keep isl_constraint *constraint,
394 enum isl_dim_type type, unsigned first, unsigned n)
395 {
396 int i;
397 isl_ctx *ctx;
398 int *active = NULL;
399 int involves = 0;
400
401 if (!constraint)
402 return -1;
403 if (n == 0)
404 return 0;
405
406 ctx = isl_constraint_get_ctx(constraint);
407 if (first + n > isl_constraint_dim(constraint, type))
408 isl_die(ctx, isl_error_invalid,
409 "range out of bounds", return -1);
410
411 active = isl_local_space_get_active(constraint->ls,
412 constraint->v->el + 1);
413 if (!active)
414 goto error;
415
416 first += isl_local_space_offset(constraint->ls, type) - 1;
417 for (i = 0; i < n; ++i)
418 if (active[first + i]) {
419 involves = 1;
420 break;
421 }
422
423 free(active);
424
425 return involves;
426 error:
427 free(active);
428 return -1;
429 }
430
431 /* Does the given constraint represent a lower bound on the given
432 * dimension?
433 */
434 int isl_constraint_is_lower_bound(__isl_keep isl_constraint *constraint,
435 enum isl_dim_type type, unsigned pos)
436 {
437 if (!constraint)
438 return -1;
439
440 if (pos >= isl_local_space_dim(constraint->ls, type))
441 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
442 "position out of bounds", return -1);
443
444 pos += isl_local_space_offset(constraint->ls, type);
445 return isl_int_is_pos(constraint->v->el[pos]);
446 }
447
448 /* Does the given constraint represent an upper bound on the given
449 * dimension?
450 */
451 int isl_constraint_is_upper_bound(__isl_keep isl_constraint *constraint,
452 enum isl_dim_type type, unsigned pos)
453 {
454 if (!constraint)
455 return -1;
456
457 if (pos >= isl_local_space_dim(constraint->ls, type))
458 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
459 "position out of bounds", return -1);
460
461 pos += isl_local_space_offset(constraint->ls, type);
462 return isl_int_is_neg(constraint->v->el[pos]);
463 }
464
465 const char *isl_constraint_get_dim_name(__isl_keep isl_constraint *constraint,
466 enum isl_dim_type type, unsigned pos)
467 {
468 return constraint ?
469 isl_local_space_get_dim_name(constraint->ls, type, pos) : NULL;
470 }
471
472 void isl_constraint_get_constant(struct isl_constraint *constraint, isl_int *v)
473 {
474 if (!constraint)
475 return;
476 isl_int_set(*v, constraint->v->el[0]);
477 }
478
479 /* Return the constant term of "constraint".
480 */
481 __isl_give isl_val *isl_constraint_get_constant_val(
482 __isl_keep isl_constraint *constraint)
483 {
484 isl_ctx *ctx;
485
486 if (!constraint)
487 return NULL;
488
489 ctx = isl_constraint_get_ctx(constraint);
490 return isl_val_int_from_isl_int(ctx, constraint->v->el[0]);
491 }
492
493 void isl_constraint_get_coefficient(struct isl_constraint *constraint,
494 enum isl_dim_type type, int pos, isl_int *v)
495 {
496 if (!constraint)
497 return;
498
499 if (pos >= isl_local_space_dim(constraint->ls, type))
500 isl_die(constraint->v->ctx, isl_error_invalid,
501 "position out of bounds", return);
502
503 pos += isl_local_space_offset(constraint->ls, type);
504 isl_int_set(*v, constraint->v->el[pos]);
505 }
506
507 /* Return the coefficient of the variable of type "type" at position "pos"
508 * of "constraint".
509 */
510 __isl_give isl_val *isl_constraint_get_coefficient_val(
511 __isl_keep isl_constraint *constraint, enum isl_dim_type type, int pos)
512 {
513 isl_ctx *ctx;
514
515 if (!constraint)
516 return NULL;
517
518 ctx = isl_constraint_get_ctx(constraint);
519 if (pos < 0 || pos >= isl_local_space_dim(constraint->ls, type))
520 isl_die(ctx, isl_error_invalid,
521 "position out of bounds", return NULL);
522
523 pos += isl_local_space_offset(constraint->ls, type);
524 return isl_val_int_from_isl_int(ctx, constraint->v->el[pos]);
525 }
526
527 __isl_give isl_aff *isl_constraint_get_div(__isl_keep isl_constraint *constraint,
528 int pos)
529 {
530 if (!constraint)
531 return NULL;
532
533 return isl_local_space_get_div(constraint->ls, pos);
534 }
535
536 __isl_give isl_constraint *isl_constraint_set_constant(
537 __isl_take isl_constraint *constraint, isl_int v)
538 {
539 constraint = isl_constraint_cow(constraint);
540 if (!constraint)
541 return NULL;
542
543 constraint->v = isl_vec_cow(constraint->v);
544 if (!constraint->v)
545 return isl_constraint_free(constraint);
546
547 isl_int_set(constraint->v->el[0], v);
548 return constraint;
549 }
550
551 /* Replace the constant term of "constraint" by "v".
552 */
553 __isl_give isl_constraint *isl_constraint_set_constant_val(
554 __isl_take isl_constraint *constraint, __isl_take isl_val *v)
555 {
556 constraint = isl_constraint_cow(constraint);
557 if (!constraint || !v)
558 goto error;
559 if (!isl_val_is_int(v))
560 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
561 "expecting integer value", goto error);
562 constraint->v = isl_vec_set_element_val(constraint->v, 0, v);
563 if (!constraint->v)
564 constraint = isl_constraint_free(constraint);
565 return constraint;
566 error:
567 isl_val_free(v);
568 return isl_constraint_free(constraint);
569 }
570
571 __isl_give isl_constraint *isl_constraint_set_constant_si(
572 __isl_take isl_constraint *constraint, int v)
573 {
574 constraint = isl_constraint_cow(constraint);
575 if (!constraint)
576 return NULL;
577
578 constraint->v = isl_vec_cow(constraint->v);
579 if (!constraint->v)
580 return isl_constraint_free(constraint);
581
582 isl_int_set_si(constraint->v->el[0], v);
583 return constraint;
584 }
585
586 __isl_give isl_constraint *isl_constraint_set_coefficient(
587 __isl_take isl_constraint *constraint,
588 enum isl_dim_type type, int pos, isl_int v)
589 {
590 constraint = isl_constraint_cow(constraint);
591 if (!constraint)
592 return NULL;
593
594 if (pos >= isl_local_space_dim(constraint->ls, type))
595 isl_die(constraint->v->ctx, isl_error_invalid,
596 "position out of bounds",
597 return isl_constraint_free(constraint));
598
599 constraint = isl_constraint_cow(constraint);
600 if (!constraint)
601 return NULL;
602
603 constraint->v = isl_vec_cow(constraint->v);
604 if (!constraint->v)
605 return isl_constraint_free(constraint);
606
607 pos += isl_local_space_offset(constraint->ls, type);
608 isl_int_set(constraint->v->el[pos], v);
609
610 return constraint;
611 }
612
613 /* Replace the coefficient of the variable of type "type" at position "pos"
614 * of "constraint" by "v".
615 */
616 __isl_give isl_constraint *isl_constraint_set_coefficient_val(
617 __isl_take isl_constraint *constraint,
618 enum isl_dim_type type, int pos, __isl_take isl_val *v)
619 {
620 constraint = isl_constraint_cow(constraint);
621 if (!constraint || !v)
622 goto error;
623 if (!isl_val_is_int(v))
624 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
625 "expecting integer value", goto error);
626
627 if (pos >= isl_local_space_dim(constraint->ls, type))
628 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
629 "position out of bounds", goto error);
630
631 pos += isl_local_space_offset(constraint->ls, type);
632 constraint->v = isl_vec_set_element_val(constraint->v, pos, v);
633 if (!constraint->v)
634 constraint = isl_constraint_free(constraint);
635 return constraint;
636 error:
637 isl_val_free(v);
638 return isl_constraint_free(constraint);
639 }
640
641 __isl_give isl_constraint *isl_constraint_set_coefficient_si(
642 __isl_take isl_constraint *constraint,
643 enum isl_dim_type type, int pos, int v)
644 {
645 constraint = isl_constraint_cow(constraint);
646 if (!constraint)
647 return NULL;
648
649 if (pos >= isl_local_space_dim(constraint->ls, type))
650 isl_die(constraint->v->ctx, isl_error_invalid,
651 "position out of bounds",
652 return isl_constraint_free(constraint));
653
654 constraint = isl_constraint_cow(constraint);
655 if (!constraint)
656 return NULL;
657
658 constraint->v = isl_vec_cow(constraint->v);
659 if (!constraint->v)
660 return isl_constraint_free(constraint);
661
662 pos += isl_local_space_offset(constraint->ls, type);
663 isl_int_set_si(constraint->v->el[pos], v);
664
665 return constraint;
666 }
667
668 /* Drop any constraint from "bset" that is identical to "constraint".
669 * In particular, this means that the local spaces of "bset" and
670 * "constraint" need to be the same.
671 *
672 * Since the given constraint may actually be a pointer into the bset,
673 * we have to be careful not to reorder the constraints as the user
674 * may be holding on to other constraints from the same bset.
675 * This should be cleaned up when the internal representation of
676 * isl_constraint is changed to use isl_aff.
677 */
678 __isl_give isl_basic_set *isl_basic_set_drop_constraint(
679 __isl_take isl_basic_set *bset, __isl_take isl_constraint *constraint)
680 {
681 int i;
682 unsigned n;
683 isl_int **row;
684 unsigned total;
685 isl_local_space *ls1;
686 int equal;
687
688 if (!bset || !constraint)
689 goto error;
690
691 ls1 = isl_basic_set_get_local_space(bset);
692 equal = isl_local_space_is_equal(ls1, constraint->ls);
693 isl_local_space_free(ls1);
694 if (equal < 0)
695 goto error;
696 if (!equal) {
697 isl_constraint_free(constraint);
698 return bset;
699 }
700
701 if (isl_constraint_is_equality(constraint)) {
702 n = bset->n_eq;
703 row = bset->eq;
704 } else {
705 n = bset->n_ineq;
706 row = bset->ineq;
707 }
708
709 total = isl_constraint_dim(constraint, isl_dim_all);
710 for (i = 0; i < n; ++i)
711 if (isl_seq_eq(row[i], constraint->v->el, 1 + total))
712 isl_seq_clr(row[i], 1 + total);
713
714 isl_constraint_free(constraint);
715 return bset;
716 error:
717 isl_constraint_free(constraint);
718 isl_basic_set_free(bset);
719 return NULL;
720 }
721
722 struct isl_constraint *isl_constraint_negate(struct isl_constraint *constraint)
723 {
724 isl_ctx *ctx;
725
726 constraint = isl_constraint_cow(constraint);
727 if (!constraint)
728 return NULL;
729
730 ctx = isl_constraint_get_ctx(constraint);
731 if (isl_constraint_is_equality(constraint))
732 isl_die(ctx, isl_error_invalid, "cannot negate equality",
733 return isl_constraint_free(constraint));
734 constraint->v = isl_vec_neg(constraint->v);
735 constraint->v = isl_vec_cow(constraint->v);
736 if (!constraint->v)
737 return isl_constraint_free(constraint);
738 isl_int_sub_ui(constraint->v->el[0], constraint->v->el[0], 1);
739 return constraint;
740 }
741
742 int isl_constraint_is_equality(struct isl_constraint *constraint)
743 {
744 if (!constraint)
745 return -1;
746 return constraint->eq;
747 }
748
749 int isl_constraint_is_div_constraint(__isl_keep isl_constraint *constraint)
750 {
751 int i;
752 int n_div;
753
754 if (!constraint)
755 return -1;
756 if (isl_constraint_is_equality(constraint))
757 return 0;
758 n_div = isl_constraint_dim(constraint, isl_dim_div);
759 for (i = 0; i < n_div; ++i) {
760 if (isl_local_space_is_div_constraint(constraint->ls,
761 constraint->v->el, i))
762 return 1;
763 }
764
765 return 0;
766 }
767
768 /* We manually set ISL_BASIC_SET_FINAL instead of calling
769 * isl_basic_map_finalize because we want to keep the position
770 * of the divs and we therefore do not want to throw away redundant divs.
771 * This is arguably a bit fragile.
772 */
773 __isl_give isl_basic_map *isl_basic_map_from_constraint(
774 __isl_take isl_constraint *constraint)
775 {
776 int k;
777 isl_local_space *ls;
778 struct isl_basic_map *bmap;
779 isl_int *c;
780 unsigned total;
781
782 if (!constraint)
783 return NULL;
784
785 ls = isl_local_space_copy(constraint->ls);
786 bmap = isl_basic_map_from_local_space(ls);
787 bmap = isl_basic_map_extend_constraints(bmap, 1, 1);
788 if (isl_constraint_is_equality(constraint)) {
789 k = isl_basic_map_alloc_equality(bmap);
790 if (k < 0)
791 goto error;
792 c = bmap->eq[k];
793 }
794 else {
795 k = isl_basic_map_alloc_inequality(bmap);
796 if (k < 0)
797 goto error;
798 c = bmap->ineq[k];
799 }
800 total = isl_basic_map_total_dim(bmap);
801 isl_seq_cpy(c, constraint->v->el, 1 + total);
802 isl_constraint_free(constraint);
803 if (bmap)
804 ISL_F_SET(bmap, ISL_BASIC_SET_FINAL);
805 return bmap;
806 error:
807 isl_constraint_free(constraint);
808 isl_basic_map_free(bmap);
809 return NULL;
810 }
811
812 struct isl_basic_set *isl_basic_set_from_constraint(
813 struct isl_constraint *constraint)
814 {
815 if (!constraint)
816 return NULL;
817
818 if (isl_constraint_dim(constraint, isl_dim_in) != 0)
819 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
820 "not a set constraint", goto error);
821 return (isl_basic_set *)isl_basic_map_from_constraint(constraint);
822 error:
823 isl_constraint_free(constraint);
824 return NULL;
825 }
826
827 int isl_basic_map_has_defining_equality(
828 __isl_keep isl_basic_map *bmap, enum isl_dim_type type, int pos,
829 __isl_give isl_constraint **c)
830 {
831 int i;
832 unsigned offset;
833 unsigned total;
834
835 if (!bmap)
836 return -1;
837 offset = basic_map_offset(bmap, type);
838 total = isl_basic_map_total_dim(bmap);
839 isl_assert(bmap->ctx, pos < isl_basic_map_dim(bmap, type), return -1);
840 for (i = 0; i < bmap->n_eq; ++i)
841 if (!isl_int_is_zero(bmap->eq[i][offset + pos]) &&
842 isl_seq_first_non_zero(bmap->eq[i]+offset+pos+1,
843 1+total-offset-pos-1) == -1) {
844 *c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
845 &bmap->eq[i]);
846 return 1;
847 }
848 return 0;
849 }
850
851 int isl_basic_set_has_defining_equality(
852 __isl_keep isl_basic_set *bset, enum isl_dim_type type, int pos,
853 __isl_give isl_constraint **c)
854 {
855 return isl_basic_map_has_defining_equality((isl_basic_map *)bset,
856 type, pos, c);
857 }
858
859 int isl_basic_set_has_defining_inequalities(
860 struct isl_basic_set *bset, enum isl_dim_type type, int pos,
861 struct isl_constraint **lower,
862 struct isl_constraint **upper)
863 {
864 int i, j;
865 unsigned offset;
866 unsigned total;
867 isl_int m;
868 isl_int **lower_line, **upper_line;
869
870 if (!bset)
871 return -1;
872 offset = basic_set_offset(bset, type);
873 total = isl_basic_set_total_dim(bset);
874 isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type), return -1);
875 isl_int_init(m);
876 for (i = 0; i < bset->n_ineq; ++i) {
877 if (isl_int_is_zero(bset->ineq[i][offset + pos]))
878 continue;
879 if (isl_int_is_one(bset->ineq[i][offset + pos]))
880 continue;
881 if (isl_int_is_negone(bset->ineq[i][offset + pos]))
882 continue;
883 if (isl_seq_first_non_zero(bset->ineq[i]+offset+pos+1,
884 1+total-offset-pos-1) != -1)
885 continue;
886 for (j = i + 1; j < bset->n_ineq; ++j) {
887 if (!isl_seq_is_neg(bset->ineq[i]+1, bset->ineq[j]+1,
888 total))
889 continue;
890 isl_int_add(m, bset->ineq[i][0], bset->ineq[j][0]);
891 if (isl_int_abs_ge(m, bset->ineq[i][offset+pos]))
892 continue;
893
894 if (isl_int_is_pos(bset->ineq[i][offset+pos])) {
895 lower_line = &bset->ineq[i];
896 upper_line = &bset->ineq[j];
897 } else {
898 lower_line = &bset->ineq[j];
899 upper_line = &bset->ineq[i];
900 }
901 *lower = isl_basic_set_constraint(
902 isl_basic_set_copy(bset), lower_line);
903 *upper = isl_basic_set_constraint(
904 isl_basic_set_copy(bset), upper_line);
905 isl_int_clear(m);
906 return 1;
907 }
908 }
909 *lower = NULL;
910 *upper = NULL;
911 isl_int_clear(m);
912 return 0;
913 }
914
915 /* Given two constraints "a" and "b" on the variable at position "abs_pos"
916 * (in "a" and "b"), add a constraint to "bset" that ensures that the
917 * bound implied by "a" is (strictly) larger than the bound implied by "b".
918 *
919 * If both constraints imply lower bounds, then this means that "a" is
920 * active in the result.
921 * If both constraints imply upper bounds, then this means that "b" is
922 * active in the result.
923 */
924 static __isl_give isl_basic_set *add_larger_bound_constraint(
925 __isl_take isl_basic_set *bset, isl_int *a, isl_int *b,
926 unsigned abs_pos, int strict)
927 {
928 int k;
929 isl_int t;
930 unsigned total;
931
932 k = isl_basic_set_alloc_inequality(bset);
933 if (k < 0)
934 goto error;
935
936 total = isl_basic_set_dim(bset, isl_dim_all);
937
938 isl_int_init(t);
939 isl_int_neg(t, b[1 + abs_pos]);
940
941 isl_seq_combine(bset->ineq[k], t, a, a[1 + abs_pos], b, 1 + abs_pos);
942 isl_seq_combine(bset->ineq[k] + 1 + abs_pos,
943 t, a + 1 + abs_pos + 1, a[1 + abs_pos], b + 1 + abs_pos + 1,
944 total - abs_pos);
945
946 if (strict)
947 isl_int_sub_ui(bset->ineq[k][0], bset->ineq[k][0], 1);
948
949 isl_int_clear(t);
950
951 return bset;
952 error:
953 isl_basic_set_free(bset);
954 return NULL;
955 }
956
957 /* Add constraints to "context" that ensure that "u" is the smallest
958 * (and therefore active) upper bound on "abs_pos" in "bset" and return
959 * the resulting basic set.
960 */
961 static __isl_give isl_basic_set *set_smallest_upper_bound(
962 __isl_keep isl_basic_set *context,
963 __isl_keep isl_basic_set *bset, unsigned abs_pos, int n_upper, int u)
964 {
965 int j;
966
967 context = isl_basic_set_copy(context);
968 context = isl_basic_set_cow(context);
969
970 context = isl_basic_set_extend_constraints(context, 0, n_upper - 1);
971
972 for (j = 0; j < bset->n_ineq; ++j) {
973 if (j == u)
974 continue;
975 if (!isl_int_is_neg(bset->ineq[j][1 + abs_pos]))
976 continue;
977 context = add_larger_bound_constraint(context,
978 bset->ineq[j], bset->ineq[u], abs_pos, j > u);
979 }
980
981 context = isl_basic_set_simplify(context);
982 context = isl_basic_set_finalize(context);
983
984 return context;
985 }
986
987 /* Add constraints to "context" that ensure that "u" is the largest
988 * (and therefore active) upper bound on "abs_pos" in "bset" and return
989 * the resulting basic set.
990 */
991 static __isl_give isl_basic_set *set_largest_lower_bound(
992 __isl_keep isl_basic_set *context,
993 __isl_keep isl_basic_set *bset, unsigned abs_pos, int n_lower, int l)
994 {
995 int j;
996
997 context = isl_basic_set_copy(context);
998 context = isl_basic_set_cow(context);
999
1000 context = isl_basic_set_extend_constraints(context, 0, n_lower - 1);
1001
1002 for (j = 0; j < bset->n_ineq; ++j) {
1003 if (j == l)
1004 continue;
1005 if (!isl_int_is_pos(bset->ineq[j][1 + abs_pos]))
1006 continue;
1007 context = add_larger_bound_constraint(context,
1008 bset->ineq[l], bset->ineq[j], abs_pos, j > l);
1009 }
1010
1011 context = isl_basic_set_simplify(context);
1012 context = isl_basic_set_finalize(context);
1013
1014 return context;
1015 }
1016
1017 static int foreach_upper_bound(__isl_keep isl_basic_set *bset,
1018 enum isl_dim_type type, unsigned abs_pos,
1019 __isl_take isl_basic_set *context, int n_upper,
1020 int (*fn)(__isl_take isl_constraint *lower,
1021 __isl_take isl_constraint *upper,
1022 __isl_take isl_basic_set *bset, void *user), void *user)
1023 {
1024 isl_basic_set *context_i;
1025 isl_constraint *upper = NULL;
1026 int i;
1027
1028 for (i = 0; i < bset->n_ineq; ++i) {
1029 if (isl_int_is_zero(bset->ineq[i][1 + abs_pos]))
1030 continue;
1031
1032 context_i = set_smallest_upper_bound(context, bset,
1033 abs_pos, n_upper, i);
1034 if (isl_basic_set_is_empty(context_i)) {
1035 isl_basic_set_free(context_i);
1036 continue;
1037 }
1038 upper = isl_basic_set_constraint(isl_basic_set_copy(bset),
1039 &bset->ineq[i]);
1040 if (!upper || !context_i)
1041 goto error;
1042 if (fn(NULL, upper, context_i, user) < 0)
1043 break;
1044 }
1045
1046 isl_basic_set_free(context);
1047
1048 if (i < bset->n_ineq)
1049 return -1;
1050
1051 return 0;
1052 error:
1053 isl_constraint_free(upper);
1054 isl_basic_set_free(context_i);
1055 isl_basic_set_free(context);
1056 return -1;
1057 }
1058
1059 static int foreach_lower_bound(__isl_keep isl_basic_set *bset,
1060 enum isl_dim_type type, unsigned abs_pos,
1061 __isl_take isl_basic_set *context, int n_lower,
1062 int (*fn)(__isl_take isl_constraint *lower,
1063 __isl_take isl_constraint *upper,
1064 __isl_take isl_basic_set *bset, void *user), void *user)
1065 {
1066 isl_basic_set *context_i;
1067 isl_constraint *lower = NULL;
1068 int i;
1069
1070 for (i = 0; i < bset->n_ineq; ++i) {
1071 if (isl_int_is_zero(bset->ineq[i][1 + abs_pos]))
1072 continue;
1073
1074 context_i = set_largest_lower_bound(context, bset,
1075 abs_pos, n_lower, i);
1076 if (isl_basic_set_is_empty(context_i)) {
1077 isl_basic_set_free(context_i);
1078 continue;
1079 }
1080 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1081 &bset->ineq[i]);
1082 if (!lower || !context_i)
1083 goto error;
1084 if (fn(lower, NULL, context_i, user) < 0)
1085 break;
1086 }
1087
1088 isl_basic_set_free(context);
1089
1090 if (i < bset->n_ineq)
1091 return -1;
1092
1093 return 0;
1094 error:
1095 isl_constraint_free(lower);
1096 isl_basic_set_free(context_i);
1097 isl_basic_set_free(context);
1098 return -1;
1099 }
1100
1101 static int foreach_bound_pair(__isl_keep isl_basic_set *bset,
1102 enum isl_dim_type type, unsigned abs_pos,
1103 __isl_take isl_basic_set *context, int n_lower, int n_upper,
1104 int (*fn)(__isl_take isl_constraint *lower,
1105 __isl_take isl_constraint *upper,
1106 __isl_take isl_basic_set *bset, void *user), void *user)
1107 {
1108 isl_basic_set *context_i, *context_j;
1109 isl_constraint *lower = NULL;
1110 isl_constraint *upper = NULL;
1111 int i, j;
1112
1113 for (i = 0; i < bset->n_ineq; ++i) {
1114 if (!isl_int_is_pos(bset->ineq[i][1 + abs_pos]))
1115 continue;
1116
1117 context_i = set_largest_lower_bound(context, bset,
1118 abs_pos, n_lower, i);
1119 if (isl_basic_set_is_empty(context_i)) {
1120 isl_basic_set_free(context_i);
1121 continue;
1122 }
1123
1124 for (j = 0; j < bset->n_ineq; ++j) {
1125 if (!isl_int_is_neg(bset->ineq[j][1 + abs_pos]))
1126 continue;
1127
1128 context_j = set_smallest_upper_bound(context_i, bset,
1129 abs_pos, n_upper, j);
1130 context_j = isl_basic_set_extend_constraints(context_j,
1131 0, 1);
1132 context_j = add_larger_bound_constraint(context_j,
1133 bset->ineq[i], bset->ineq[j], abs_pos, 0);
1134 context_j = isl_basic_set_simplify(context_j);
1135 context_j = isl_basic_set_finalize(context_j);
1136 if (isl_basic_set_is_empty(context_j)) {
1137 isl_basic_set_free(context_j);
1138 continue;
1139 }
1140 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1141 &bset->ineq[i]);
1142 upper = isl_basic_set_constraint(isl_basic_set_copy(bset),
1143 &bset->ineq[j]);
1144 if (!lower || !upper || !context_j)
1145 goto error;
1146 if (fn(lower, upper, context_j, user) < 0)
1147 break;
1148 }
1149
1150 isl_basic_set_free(context_i);
1151
1152 if (j < bset->n_ineq)
1153 break;
1154 }
1155
1156 isl_basic_set_free(context);
1157
1158 if (i < bset->n_ineq)
1159 return -1;
1160
1161 return 0;
1162 error:
1163 isl_constraint_free(lower);
1164 isl_constraint_free(upper);
1165 isl_basic_set_free(context_i);
1166 isl_basic_set_free(context_j);
1167 isl_basic_set_free(context);
1168 return -1;
1169 }
1170
1171 /* For each pair of lower and upper bounds on the variable "pos"
1172 * of type "type", call "fn" with these lower and upper bounds and the
1173 * set of constraints on the remaining variables where these bounds
1174 * are active, i.e., (stricly) larger/smaller than the other lower/upper bounds.
1175 *
1176 * If the designated variable is equal to an affine combination of the
1177 * other variables then fn is called with both lower and upper
1178 * set to the corresponding equality.
1179 *
1180 * If there is no lower (or upper) bound, then NULL is passed
1181 * as the corresponding bound.
1182 *
1183 * We first check if the variable is involved in any equality.
1184 * If not, we count the number of lower and upper bounds and
1185 * act accordingly.
1186 */
1187 int isl_basic_set_foreach_bound_pair(__isl_keep isl_basic_set *bset,
1188 enum isl_dim_type type, unsigned pos,
1189 int (*fn)(__isl_take isl_constraint *lower,
1190 __isl_take isl_constraint *upper,
1191 __isl_take isl_basic_set *bset, void *user), void *user)
1192 {
1193 int i;
1194 isl_constraint *lower = NULL;
1195 isl_constraint *upper = NULL;
1196 isl_basic_set *context = NULL;
1197 unsigned abs_pos;
1198 int n_lower, n_upper;
1199
1200 if (!bset)
1201 return -1;
1202 isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type), return -1);
1203 isl_assert(bset->ctx, type == isl_dim_param || type == isl_dim_set,
1204 return -1);
1205
1206 abs_pos = pos;
1207 if (type == isl_dim_set)
1208 abs_pos += isl_basic_set_dim(bset, isl_dim_param);
1209
1210 for (i = 0; i < bset->n_eq; ++i) {
1211 if (isl_int_is_zero(bset->eq[i][1 + abs_pos]))
1212 continue;
1213
1214 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1215 &bset->eq[i]);
1216 upper = isl_constraint_copy(lower);
1217 context = isl_basic_set_remove_dims(isl_basic_set_copy(bset),
1218 type, pos, 1);
1219 if (!lower || !upper || !context)
1220 goto error;
1221 return fn(lower, upper, context, user);
1222 }
1223
1224 n_lower = 0;
1225 n_upper = 0;
1226 for (i = 0; i < bset->n_ineq; ++i) {
1227 if (isl_int_is_pos(bset->ineq[i][1 + abs_pos]))
1228 n_lower++;
1229 else if (isl_int_is_neg(bset->ineq[i][1 + abs_pos]))
1230 n_upper++;
1231 }
1232
1233 context = isl_basic_set_copy(bset);
1234 context = isl_basic_set_cow(context);
1235 if (!context)
1236 goto error;
1237 for (i = context->n_ineq - 1; i >= 0; --i)
1238 if (!isl_int_is_zero(context->ineq[i][1 + abs_pos]))
1239 isl_basic_set_drop_inequality(context, i);
1240
1241 context = isl_basic_set_drop(context, type, pos, 1);
1242 if (!n_lower && !n_upper)
1243 return fn(NULL, NULL, context, user);
1244 if (!n_lower)
1245 return foreach_upper_bound(bset, type, abs_pos, context, n_upper,
1246 fn, user);
1247 if (!n_upper)
1248 return foreach_lower_bound(bset, type, abs_pos, context, n_lower,
1249 fn, user);
1250 return foreach_bound_pair(bset, type, abs_pos, context, n_lower, n_upper,
1251 fn, user);
1252 error:
1253 isl_constraint_free(lower);
1254 isl_constraint_free(upper);
1255 isl_basic_set_free(context);
1256 return -1;
1257 }
1258
1259 __isl_give isl_aff *isl_constraint_get_bound(
1260 __isl_keep isl_constraint *constraint, enum isl_dim_type type, int pos)
1261 {
1262 isl_aff *aff;
1263 isl_ctx *ctx;
1264
1265 if (!constraint)
1266 return NULL;
1267 ctx = isl_constraint_get_ctx(constraint);
1268 if (pos >= isl_constraint_dim(constraint, type))
1269 isl_die(ctx, isl_error_invalid,
1270 "index out of bounds", return NULL);
1271 if (isl_constraint_dim(constraint, isl_dim_in) != 0)
1272 isl_die(ctx, isl_error_invalid,
1273 "not a set constraint", return NULL);
1274
1275 pos += offset(constraint, type);
1276 if (isl_int_is_zero(constraint->v->el[pos]))
1277 isl_die(ctx, isl_error_invalid,
1278 "constraint does not define a bound on given dimension",
1279 return NULL);
1280
1281 aff = isl_aff_alloc(isl_local_space_copy(constraint->ls));
1282 if (!aff)
1283 return NULL;
1284
1285 if (isl_int_is_neg(constraint->v->el[pos]))
1286 isl_seq_cpy(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1287 else
1288 isl_seq_neg(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1289 isl_int_set_si(aff->v->el[1 + pos], 0);
1290 isl_int_abs(aff->v->el[0], constraint->v->el[pos]);
1291
1292 return aff;
1293 }
1294
1295 /* For an inequality constraint
1296 *
1297 * f >= 0
1298 *
1299 * or an equality constraint
1300 *
1301 * f = 0
1302 *
1303 * return the affine expression f.
1304 */
1305 __isl_give isl_aff *isl_constraint_get_aff(
1306 __isl_keep isl_constraint *constraint)
1307 {
1308 isl_aff *aff;
1309
1310 if (!constraint)
1311 return NULL;
1312
1313 aff = isl_aff_alloc(isl_local_space_copy(constraint->ls));
1314 if (!aff)
1315 return NULL;
1316
1317 isl_seq_cpy(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1318 isl_int_set_si(aff->v->el[0], 1);
1319
1320 return aff;
1321 }
1322
1323 /* Construct an inequality (eq = 0) or equality (eq = 1) constraint from "aff".
1324 * In particular, construct aff >= 0 or aff = 0.
1325 *
1326 * The denominator of "aff" can be ignored.
1327 */
1328 static __isl_give isl_constraint *isl_constraint_alloc_aff(int eq,
1329 __isl_take isl_aff *aff)
1330 {
1331 isl_local_space *ls;
1332 isl_vec *v;
1333
1334 if (!aff)
1335 return NULL;
1336 ls = isl_aff_get_domain_local_space(aff);
1337 v = isl_vec_drop_els(isl_vec_copy(aff->v), 0, 1);
1338 isl_aff_free(aff);
1339
1340 return isl_constraint_alloc_vec(eq, ls, v);
1341 }
1342
1343 /* Construct an equality constraint equating the given affine expression
1344 * to zero.
1345 */
1346 __isl_give isl_constraint *isl_equality_from_aff(__isl_take isl_aff *aff)
1347 {
1348 return isl_constraint_alloc_aff(1, aff);
1349 }
1350
1351 /* Construct an inequality constraint enforcing the given affine expression
1352 * to be non-negative.
1353 */
1354 __isl_give isl_constraint *isl_inequality_from_aff(__isl_take isl_aff *aff)
1355 {
1356 return isl_constraint_alloc_aff(0, aff);
1357 }
1358
1359 /* Compare two isl_constraints.
1360 *
1361 * Return -1 if "c1" is "smaller" than "c2", 1 if "c1" is "greater"
1362 * than "c2" and 0 if they are equal.
1363 *
1364 * The order is fairly arbitrary. We do consider constraints that only involve
1365 * earlier dimensions as "smaller".
1366 */
1367 int isl_constraint_plain_cmp(__isl_keep isl_constraint *c1,
1368 __isl_keep isl_constraint *c2)
1369 {
1370 int cmp;
1371 int last1, last2;
1372
1373 if (c1 == c2)
1374 return 0;
1375 if (!c1)
1376 return -1;
1377 if (!c2)
1378 return 1;
1379 cmp = isl_local_space_cmp(c1->ls, c2->ls);
1380 if (cmp != 0)
1381 return cmp;
1382
1383 last1 = isl_seq_last_non_zero(c1->v->el + 1, c1->v->size - 1);
1384 last2 = isl_seq_last_non_zero(c2->v->el + 1, c1->v->size - 1);
1385 if (last1 != last2)
1386 return last1 - last2;
1387
1388 return isl_seq_cmp(c1->v->el, c2->v->el, c1->v->size);
1389 }
1390
1391 /* Compare two constraints based on their final (non-zero) coefficients.
1392 * In particular, the constraint that involves later variables or
1393 * that has a larger coefficient for a shared latest variable
1394 * is considered "greater" than the other constraint.
1395 *
1396 * Return -1 if "c1" is "smaller" than "c2", 1 if "c1" is "greater"
1397 * than "c2" and 0 if they are equal.
1398 *
1399 * If the constraints live in different local spaces, then we cannot
1400 * really compare the constraints so we compare the local spaces instead.
1401 */
1402 int isl_constraint_cmp_last_non_zero(__isl_keep isl_constraint *c1,
1403 __isl_keep isl_constraint *c2)
1404 {
1405 int cmp;
1406 int last1, last2;
1407
1408 if (c1 == c2)
1409 return 0;
1410 if (!c1)
1411 return -1;
1412 if (!c2)
1413 return 1;
1414 cmp = isl_local_space_cmp(c1->ls, c2->ls);
1415 if (cmp != 0)
1416 return cmp;
1417
1418 last1 = isl_seq_last_non_zero(c1->v->el + 1, c1->v->size - 1);
1419 last2 = isl_seq_last_non_zero(c2->v->el + 1, c1->v->size - 1);
1420 if (last1 != last2)
1421 return last1 - last2;
1422 if (last1 == -1)
1423 return 0;
1424 return isl_int_abs_cmp(c1->v->el[1 + last1], c2->v->el[1 + last2]);
1425 }
Integer set library