?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
isl_map_coalesce: fix stride constraint integer division harmonization
[isl.git] / isl_constraint.c
blob7612559a9ac2a1449533f9ef27f87938472bd10b
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
22 #include <bset_to_bmap.c>
23 #include <bset_from_bmap.c>
24
25 #undef BASE
26 #define BASE constraint
27
28 #include <isl_list_templ.c>
29
30 isl_ctx *isl_constraint_get_ctx(__isl_keep isl_constraint *c)
31 {
32 return c ? isl_local_space_get_ctx(c->ls) : NULL;
33 }
34
35 static unsigned n(struct isl_constraint *c, enum isl_dim_type type)
36 {
37 return isl_local_space_dim(c->ls, type);
38 }
39
40 static unsigned offset(struct isl_constraint *c, enum isl_dim_type type)
41 {
42 return isl_local_space_offset(c->ls, type);
43 }
44
45 static unsigned basic_map_offset(__isl_keep isl_basic_map *bmap,
46 enum isl_dim_type type)
47 {
48 return type == isl_dim_div ? 1 + isl_space_dim(bmap->dim, isl_dim_all)
49 : 1 + isl_space_offset(bmap->dim, type);
50 }
51
52 static unsigned basic_set_offset(struct isl_basic_set *bset,
53 enum isl_dim_type type)
54 {
55 isl_space *dim = bset->dim;
56 switch (type) {
57 case isl_dim_param: return 1;
58 case isl_dim_in: return 1 + dim->nparam;
59 case isl_dim_out: return 1 + dim->nparam + dim->n_in;
60 case isl_dim_div: return 1 + dim->nparam + dim->n_in + dim->n_out;
61 default: return 0;
62 }
63 }
64
65 __isl_give isl_constraint *isl_constraint_alloc_vec(int eq,
66 __isl_take isl_local_space *ls, __isl_take isl_vec *v)
67 {
68 isl_constraint *constraint;
69
70 if (!ls || !v)
71 goto error;
72
73 constraint = isl_alloc_type(isl_vec_get_ctx(v), isl_constraint);
74 if (!constraint)
75 goto error;
76
77 constraint->ref = 1;
78 constraint->eq = eq;
79 constraint->ls = ls;
80 constraint->v = v;
81
82 return constraint;
83 error:
84 isl_local_space_free(ls);
85 isl_vec_free(v);
86 return NULL;
87 }
88
89 __isl_give isl_constraint *isl_constraint_alloc(int eq,
90 __isl_take isl_local_space *ls)
91 {
92 isl_ctx *ctx;
93 isl_vec *v;
94
95 if (!ls)
96 return NULL;
97
98 ctx = isl_local_space_get_ctx(ls);
99 v = isl_vec_alloc(ctx, 1 + isl_local_space_dim(ls, isl_dim_all));
100 v = isl_vec_clr(v);
101 return isl_constraint_alloc_vec(eq, ls, v);
102 }
103
104 struct isl_constraint *isl_basic_map_constraint(struct isl_basic_map *bmap,
105 isl_int **line)
106 {
107 int eq;
108 isl_ctx *ctx;
109 isl_vec *v;
110 isl_local_space *ls = NULL;
111 isl_constraint *constraint;
112
113 if (!bmap || !line)
114 goto error;
115
116 eq = line >= bmap->eq;
117
118 ctx = isl_basic_map_get_ctx(bmap);
119 ls = isl_basic_map_get_local_space(bmap);
120 v = isl_vec_alloc(ctx, 1 + isl_local_space_dim(ls, isl_dim_all));
121 if (!v)
122 goto error;
123 isl_seq_cpy(v->el, line[0], v->size);
124 constraint = isl_constraint_alloc_vec(eq, ls, v);
125
126 isl_basic_map_free(bmap);
127 return constraint;
128 error:
129 isl_local_space_free(ls);
130 isl_basic_map_free(bmap);
131 return NULL;
132 }
133
134 struct isl_constraint *isl_basic_set_constraint(struct isl_basic_set *bset,
135 isl_int **line)
136 {
137 return isl_basic_map_constraint(bset_to_bmap(bset), line);
138 }
139
140 __isl_give isl_constraint *isl_constraint_alloc_equality(
141 __isl_take isl_local_space *ls)
142 {
143 return isl_constraint_alloc(1, ls);
144 }
145
146 __isl_give isl_constraint *isl_constraint_alloc_inequality(
147 __isl_take isl_local_space *ls)
148 {
149 return isl_constraint_alloc(0, ls);
150 }
151
152 struct isl_constraint *isl_constraint_dup(struct isl_constraint *c)
153 {
154 if (!c)
155 return NULL;
156
157 return isl_constraint_alloc_vec(c->eq, isl_local_space_copy(c->ls),
158 isl_vec_copy(c->v));
159 }
160
161 struct isl_constraint *isl_constraint_cow(struct isl_constraint *c)
162 {
163 if (!c)
164 return NULL;
165
166 if (c->ref == 1)
167 return c;
168 c->ref--;
169 return isl_constraint_dup(c);
170 }
171
172 struct isl_constraint *isl_constraint_copy(struct isl_constraint *constraint)
173 {
174 if (!constraint)
175 return NULL;
176
177 constraint->ref++;
178 return constraint;
179 }
180
181 __isl_null isl_constraint *isl_constraint_free(__isl_take isl_constraint *c)
182 {
183 if (!c)
184 return NULL;
185
186 if (--c->ref > 0)
187 return NULL;
188
189 isl_local_space_free(c->ls);
190 isl_vec_free(c->v);
191 free(c);
192
193 return NULL;
194 }
195
196 /* Return the number of constraints in "bmap", i.e., the
197 * number of times isl_basic_map_foreach_constraint will
198 * call the callback.
199 */
200 int isl_basic_map_n_constraint(__isl_keep isl_basic_map *bmap)
201 {
202 if (!bmap)
203 return -1;
204
205 return bmap->n_eq + bmap->n_ineq;
206 }
207
208 /* Return the number of constraints in "bset", i.e., the
209 * number of times isl_basic_set_foreach_constraint will
210 * call the callback.
211 */
212 int isl_basic_set_n_constraint(__isl_keep isl_basic_set *bset)
213 {
214 return isl_basic_map_n_constraint(bset);
215 }
216
217 isl_stat isl_basic_map_foreach_constraint(__isl_keep isl_basic_map *bmap,
218 isl_stat (*fn)(__isl_take isl_constraint *c, void *user), void *user)
219 {
220 int i;
221 struct isl_constraint *c;
222
223 if (!bmap)
224 return isl_stat_error;
225
226 isl_assert(bmap->ctx, ISL_F_ISSET(bmap, ISL_BASIC_MAP_FINAL),
227 return isl_stat_error);
228
229 for (i = 0; i < bmap->n_eq; ++i) {
230 c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
231 &bmap->eq[i]);
232 if (!c)
233 return isl_stat_error;
234 if (fn(c, user) < 0)
235 return isl_stat_error;
236 }
237
238 for (i = 0; i < bmap->n_ineq; ++i) {
239 c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
240 &bmap->ineq[i]);
241 if (!c)
242 return isl_stat_error;
243 if (fn(c, user) < 0)
244 return isl_stat_error;
245 }
246
247 return isl_stat_ok;
248 }
249
250 isl_stat isl_basic_set_foreach_constraint(__isl_keep isl_basic_set *bset,
251 isl_stat (*fn)(__isl_take isl_constraint *c, void *user), void *user)
252 {
253 return isl_basic_map_foreach_constraint(bset_to_bmap(bset), fn, user);
254 }
255
256 /* Add the constraint to the list that "user" points to, if it is not
257 * a div constraint.
258 */
259 static isl_stat collect_constraint(__isl_take isl_constraint *constraint,
260 void *user)
261 {
262 isl_constraint_list **list = user;
263
264 if (isl_constraint_is_div_constraint(constraint))
265 isl_constraint_free(constraint);
266 else
267 *list = isl_constraint_list_add(*list, constraint);
268
269 return isl_stat_ok;
270 }
271
272 /* Return a list of constraints that, when combined, are equivalent
273 * to "bmap". The input is required to have only known divs.
274 *
275 * There is no need to include the div constraints as they are
276 * implied by the div expressions.
277 */
278 __isl_give isl_constraint_list *isl_basic_map_get_constraint_list(
279 __isl_keep isl_basic_map *bmap)
280 {
281 int n;
282 int known;
283 isl_ctx *ctx;
284 isl_constraint_list *list;
285
286 known = isl_basic_map_divs_known(bmap);
287 if (known < 0)
288 return NULL;
289 ctx = isl_basic_map_get_ctx(bmap);
290 if (!known)
291 isl_die(ctx, isl_error_invalid,
292 "input involves unknown divs", return NULL);
293
294 n = isl_basic_map_n_constraint(bmap);
295 list = isl_constraint_list_alloc(ctx, n);
296 if (isl_basic_map_foreach_constraint(bmap,
297 &collect_constraint, &list) < 0)
298 list = isl_constraint_list_free(list);
299
300 return list;
301 }
302
303 /* Return a list of constraints that, when combined, are equivalent
304 * to "bset". The input is required to have only known divs.
305 */
306 __isl_give isl_constraint_list *isl_basic_set_get_constraint_list(
307 __isl_keep isl_basic_set *bset)
308 {
309 return isl_basic_map_get_constraint_list(bset);
310 }
311
312 int isl_constraint_is_equal(struct isl_constraint *constraint1,
313 struct isl_constraint *constraint2)
314 {
315 int equal;
316
317 if (!constraint1 || !constraint2)
318 return 0;
319 if (constraint1->eq != constraint2->eq)
320 return 0;
321 equal = isl_local_space_is_equal(constraint1->ls, constraint2->ls);
322 if (equal < 0 || !equal)
323 return equal;
324 return isl_vec_is_equal(constraint1->v, constraint2->v);
325 }
326
327 struct isl_basic_map *isl_basic_map_add_constraint(
328 struct isl_basic_map *bmap, struct isl_constraint *constraint)
329 {
330 isl_ctx *ctx;
331 isl_space *dim;
332 int equal_space;
333
334 if (!bmap || !constraint)
335 goto error;
336
337 ctx = isl_constraint_get_ctx(constraint);
338 dim = isl_constraint_get_space(constraint);
339 equal_space = isl_space_is_equal(bmap->dim, dim);
340 isl_space_free(dim);
341 isl_assert(ctx, equal_space, goto error);
342
343 bmap = isl_basic_map_intersect(bmap,
344 isl_basic_map_from_constraint(constraint));
345 return bmap;
346 error:
347 isl_basic_map_free(bmap);
348 isl_constraint_free(constraint);
349 return NULL;
350 }
351
352 struct isl_basic_set *isl_basic_set_add_constraint(
353 struct isl_basic_set *bset, struct isl_constraint *constraint)
354 {
355 return bset_from_bmap(isl_basic_map_add_constraint(bset_to_bmap(bset),
356 constraint));
357 }
358
359 __isl_give isl_map *isl_map_add_constraint(__isl_take isl_map *map,
360 __isl_take isl_constraint *constraint)
361 {
362 isl_basic_map *bmap;
363
364 bmap = isl_basic_map_from_constraint(constraint);
365 map = isl_map_intersect(map, isl_map_from_basic_map(bmap));
366
367 return map;
368 }
369
370 __isl_give isl_set *isl_set_add_constraint(__isl_take isl_set *set,
371 __isl_take isl_constraint *constraint)
372 {
373 return isl_map_add_constraint(set, constraint);
374 }
375
376 __isl_give isl_space *isl_constraint_get_space(
377 __isl_keep isl_constraint *constraint)
378 {
379 return constraint ? isl_local_space_get_space(constraint->ls) : NULL;
380 }
381
382 __isl_give isl_local_space *isl_constraint_get_local_space(
383 __isl_keep isl_constraint *constraint)
384 {
385 return constraint ? isl_local_space_copy(constraint->ls) : NULL;
386 }
387
388 int isl_constraint_dim(struct isl_constraint *constraint,
389 enum isl_dim_type type)
390 {
391 if (!constraint)
392 return -1;
393 return n(constraint, type);
394 }
395
396 isl_bool isl_constraint_involves_dims(__isl_keep isl_constraint *constraint,
397 enum isl_dim_type type, unsigned first, unsigned n)
398 {
399 int i;
400 isl_ctx *ctx;
401 int *active = NULL;
402 isl_bool involves = isl_bool_false;
403
404 if (!constraint)
405 return isl_bool_error;
406 if (n == 0)
407 return isl_bool_false;
408
409 ctx = isl_constraint_get_ctx(constraint);
410 if (first + n > isl_constraint_dim(constraint, type))
411 isl_die(ctx, isl_error_invalid,
412 "range out of bounds", return isl_bool_error);
413
414 active = isl_local_space_get_active(constraint->ls,
415 constraint->v->el + 1);
416 if (!active)
417 goto error;
418
419 first += isl_local_space_offset(constraint->ls, type) - 1;
420 for (i = 0; i < n; ++i)
421 if (active[first + i]) {
422 involves = isl_bool_true;
423 break;
424 }
425
426 free(active);
427
428 return involves;
429 error:
430 free(active);
431 return isl_bool_error;
432 }
433
434 /* Does the given constraint represent a lower bound on the given
435 * dimension?
436 */
437 isl_bool isl_constraint_is_lower_bound(__isl_keep isl_constraint *constraint,
438 enum isl_dim_type type, unsigned pos)
439 {
440 if (!constraint)
441 return isl_bool_error;
442
443 if (pos >= isl_local_space_dim(constraint->ls, type))
444 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
445 "position out of bounds", return isl_bool_error);
446
447 pos += isl_local_space_offset(constraint->ls, type);
448 return isl_int_is_pos(constraint->v->el[pos]);
449 }
450
451 /* Does the given constraint represent an upper bound on the given
452 * dimension?
453 */
454 isl_bool isl_constraint_is_upper_bound(__isl_keep isl_constraint *constraint,
455 enum isl_dim_type type, unsigned pos)
456 {
457 if (!constraint)
458 return isl_bool_error;
459
460 if (pos >= isl_local_space_dim(constraint->ls, type))
461 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
462 "position out of bounds", return isl_bool_error);
463
464 pos += isl_local_space_offset(constraint->ls, type);
465 return isl_int_is_neg(constraint->v->el[pos]);
466 }
467
468 const char *isl_constraint_get_dim_name(__isl_keep isl_constraint *constraint,
469 enum isl_dim_type type, unsigned pos)
470 {
471 return constraint ?
472 isl_local_space_get_dim_name(constraint->ls, type, pos) : NULL;
473 }
474
475 void isl_constraint_get_constant(__isl_keep isl_constraint *constraint,
476 isl_int *v)
477 {
478 if (!constraint)
479 return;
480 isl_int_set(*v, constraint->v->el[0]);
481 }
482
483 /* Return the constant term of "constraint".
484 */
485 __isl_give isl_val *isl_constraint_get_constant_val(
486 __isl_keep isl_constraint *constraint)
487 {
488 isl_ctx *ctx;
489
490 if (!constraint)
491 return NULL;
492
493 ctx = isl_constraint_get_ctx(constraint);
494 return isl_val_int_from_isl_int(ctx, constraint->v->el[0]);
495 }
496
497 void isl_constraint_get_coefficient(struct isl_constraint *constraint,
498 enum isl_dim_type type, int pos, isl_int *v)
499 {
500 if (!constraint)
501 return;
502
503 if (pos >= isl_local_space_dim(constraint->ls, type))
504 isl_die(constraint->v->ctx, isl_error_invalid,
505 "position out of bounds", return);
506
507 pos += isl_local_space_offset(constraint->ls, type);
508 isl_int_set(*v, constraint->v->el[pos]);
509 }
510
511 /* Return the coefficient of the variable of type "type" at position "pos"
512 * of "constraint".
513 */
514 __isl_give isl_val *isl_constraint_get_coefficient_val(
515 __isl_keep isl_constraint *constraint, enum isl_dim_type type, int pos)
516 {
517 isl_ctx *ctx;
518
519 if (!constraint)
520 return NULL;
521
522 ctx = isl_constraint_get_ctx(constraint);
523 if (pos < 0 || pos >= isl_local_space_dim(constraint->ls, type))
524 isl_die(ctx, isl_error_invalid,
525 "position out of bounds", return NULL);
526
527 pos += isl_local_space_offset(constraint->ls, type);
528 return isl_val_int_from_isl_int(ctx, constraint->v->el[pos]);
529 }
530
531 __isl_give isl_aff *isl_constraint_get_div(__isl_keep isl_constraint *constraint,
532 int pos)
533 {
534 if (!constraint)
535 return NULL;
536
537 return isl_local_space_get_div(constraint->ls, pos);
538 }
539
540 __isl_give isl_constraint *isl_constraint_set_constant(
541 __isl_take isl_constraint *constraint, isl_int v)
542 {
543 constraint = isl_constraint_cow(constraint);
544 if (!constraint)
545 return NULL;
546
547 constraint->v = isl_vec_cow(constraint->v);
548 if (!constraint->v)
549 return isl_constraint_free(constraint);
550
551 isl_int_set(constraint->v->el[0], v);
552 return constraint;
553 }
554
555 /* Replace the constant term of "constraint" by "v".
556 */
557 __isl_give isl_constraint *isl_constraint_set_constant_val(
558 __isl_take isl_constraint *constraint, __isl_take isl_val *v)
559 {
560 constraint = isl_constraint_cow(constraint);
561 if (!constraint || !v)
562 goto error;
563 if (!isl_val_is_int(v))
564 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
565 "expecting integer value", goto error);
566 constraint->v = isl_vec_set_element_val(constraint->v, 0, v);
567 if (!constraint->v)
568 constraint = isl_constraint_free(constraint);
569 return constraint;
570 error:
571 isl_val_free(v);
572 return isl_constraint_free(constraint);
573 }
574
575 __isl_give isl_constraint *isl_constraint_set_constant_si(
576 __isl_take isl_constraint *constraint, int v)
577 {
578 constraint = isl_constraint_cow(constraint);
579 if (!constraint)
580 return NULL;
581
582 constraint->v = isl_vec_cow(constraint->v);
583 if (!constraint->v)
584 return isl_constraint_free(constraint);
585
586 isl_int_set_si(constraint->v->el[0], v);
587 return constraint;
588 }
589
590 __isl_give isl_constraint *isl_constraint_set_coefficient(
591 __isl_take isl_constraint *constraint,
592 enum isl_dim_type type, int pos, isl_int v)
593 {
594 constraint = isl_constraint_cow(constraint);
595 if (!constraint)
596 return NULL;
597
598 if (pos >= isl_local_space_dim(constraint->ls, type))
599 isl_die(constraint->v->ctx, isl_error_invalid,
600 "position out of bounds",
601 return isl_constraint_free(constraint));
602
603 constraint = isl_constraint_cow(constraint);
604 if (!constraint)
605 return NULL;
606
607 constraint->v = isl_vec_cow(constraint->v);
608 if (!constraint->v)
609 return isl_constraint_free(constraint);
610
611 pos += isl_local_space_offset(constraint->ls, type);
612 isl_int_set(constraint->v->el[pos], v);
613
614 return constraint;
615 }
616
617 /* Replace the coefficient of the variable of type "type" at position "pos"
618 * of "constraint" by "v".
619 */
620 __isl_give isl_constraint *isl_constraint_set_coefficient_val(
621 __isl_take isl_constraint *constraint,
622 enum isl_dim_type type, int pos, __isl_take isl_val *v)
623 {
624 constraint = isl_constraint_cow(constraint);
625 if (!constraint || !v)
626 goto error;
627 if (!isl_val_is_int(v))
628 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
629 "expecting integer value", goto error);
630
631 if (pos >= isl_local_space_dim(constraint->ls, type))
632 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
633 "position out of bounds", goto error);
634
635 pos += isl_local_space_offset(constraint->ls, type);
636 constraint->v = isl_vec_set_element_val(constraint->v, pos, v);
637 if (!constraint->v)
638 constraint = isl_constraint_free(constraint);
639 return constraint;
640 error:
641 isl_val_free(v);
642 return isl_constraint_free(constraint);
643 }
644
645 __isl_give isl_constraint *isl_constraint_set_coefficient_si(
646 __isl_take isl_constraint *constraint,
647 enum isl_dim_type type, int pos, int v)
648 {
649 constraint = isl_constraint_cow(constraint);
650 if (!constraint)
651 return NULL;
652
653 if (pos >= isl_local_space_dim(constraint->ls, type))
654 isl_die(constraint->v->ctx, isl_error_invalid,
655 "position out of bounds",
656 return isl_constraint_free(constraint));
657
658 constraint = isl_constraint_cow(constraint);
659 if (!constraint)
660 return NULL;
661
662 constraint->v = isl_vec_cow(constraint->v);
663 if (!constraint->v)
664 return isl_constraint_free(constraint);
665
666 pos += isl_local_space_offset(constraint->ls, type);
667 isl_int_set_si(constraint->v->el[pos], v);
668
669 return constraint;
670 }
671
672 struct isl_constraint *isl_constraint_negate(struct isl_constraint *constraint)
673 {
674 isl_ctx *ctx;
675
676 constraint = isl_constraint_cow(constraint);
677 if (!constraint)
678 return NULL;
679
680 ctx = isl_constraint_get_ctx(constraint);
681 if (isl_constraint_is_equality(constraint))
682 isl_die(ctx, isl_error_invalid, "cannot negate equality",
683 return isl_constraint_free(constraint));
684 constraint->v = isl_vec_neg(constraint->v);
685 constraint->v = isl_vec_cow(constraint->v);
686 if (!constraint->v)
687 return isl_constraint_free(constraint);
688 isl_int_sub_ui(constraint->v->el[0], constraint->v->el[0], 1);
689 return constraint;
690 }
691
692 isl_bool isl_constraint_is_equality(struct isl_constraint *constraint)
693 {
694 if (!constraint)
695 return isl_bool_error;
696 return constraint->eq;
697 }
698
699 int isl_constraint_is_div_constraint(__isl_keep isl_constraint *constraint)
700 {
701 int i;
702 int n_div;
703
704 if (!constraint)
705 return -1;
706 if (isl_constraint_is_equality(constraint))
707 return 0;
708 n_div = isl_constraint_dim(constraint, isl_dim_div);
709 for (i = 0; i < n_div; ++i) {
710 isl_bool is_div;
711 is_div = isl_local_space_is_div_constraint(constraint->ls,
712 constraint->v->el, i);
713 if (is_div < 0 || is_div)
714 return is_div;
715 }
716
717 return 0;
718 }
719
720 /* Is "constraint" an equality that corresponds to integer division "div"?
721 *
722 * That is, given an integer division of the form
723 *
724 * a = floor((f + c)/m)
725 *
726 * is the equality of the form
727 *
728 * -f + m d + c' = 0
729 * ?
730 * Note that the constant term is not checked explicitly, but given
731 * that this is a valid equality constraint, the constant c' necessarily
732 * has a value close to -c.
733 */
734 isl_bool isl_constraint_is_div_equality(__isl_keep isl_constraint *constraint,
735 unsigned div)
736 {
737 isl_bool equality;
738
739 equality = isl_constraint_is_equality(constraint);
740 if (equality < 0 || !equality)
741 return equality;
742 return isl_local_space_is_div_equality(constraint->ls,
743 constraint->v->el, div);
744 }
745
746 /* We manually set ISL_BASIC_SET_FINAL instead of calling
747 * isl_basic_map_finalize because we want to keep the position
748 * of the divs and we therefore do not want to throw away redundant divs.
749 * This is arguably a bit fragile.
750 */
751 __isl_give isl_basic_map *isl_basic_map_from_constraint(
752 __isl_take isl_constraint *constraint)
753 {
754 int k;
755 isl_local_space *ls;
756 struct isl_basic_map *bmap;
757 isl_int *c;
758 unsigned total;
759
760 if (!constraint)
761 return NULL;
762
763 ls = isl_local_space_copy(constraint->ls);
764 bmap = isl_basic_map_from_local_space(ls);
765 bmap = isl_basic_map_extend_constraints(bmap, 1, 1);
766 if (isl_constraint_is_equality(constraint)) {
767 k = isl_basic_map_alloc_equality(bmap);
768 if (k < 0)
769 goto error;
770 c = bmap->eq[k];
771 }
772 else {
773 k = isl_basic_map_alloc_inequality(bmap);
774 if (k < 0)
775 goto error;
776 c = bmap->ineq[k];
777 }
778 total = isl_basic_map_total_dim(bmap);
779 isl_seq_cpy(c, constraint->v->el, 1 + total);
780 isl_constraint_free(constraint);
781 if (bmap)
782 ISL_F_SET(bmap, ISL_BASIC_SET_FINAL);
783 return bmap;
784 error:
785 isl_constraint_free(constraint);
786 isl_basic_map_free(bmap);
787 return NULL;
788 }
789
790 __isl_give isl_basic_set *isl_basic_set_from_constraint(
791 __isl_take isl_constraint *constraint)
792 {
793 if (!constraint)
794 return NULL;
795
796 if (isl_constraint_dim(constraint, isl_dim_in) != 0)
797 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
798 "not a set constraint", goto error);
799 return bset_from_bmap(isl_basic_map_from_constraint(constraint));
800 error:
801 isl_constraint_free(constraint);
802 return NULL;
803 }
804
805 /* Is the variable of "type" at position "pos" of "bmap" defined
806 * in terms of earlier dimensions through an equality?
807 *
808 * If so, and if c is not NULL, then return a copy of this equality in *c.
809 */
810 isl_bool isl_basic_map_has_defining_equality(
811 __isl_keep isl_basic_map *bmap, enum isl_dim_type type, int pos,
812 __isl_give isl_constraint **c)
813 {
814 int i;
815 unsigned offset;
816 unsigned total;
817
818 if (!bmap)
819 return isl_bool_error;
820 offset = basic_map_offset(bmap, type);
821 total = isl_basic_map_total_dim(bmap);
822 if (pos >= isl_basic_map_dim(bmap, type))
823 isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
824 "invalid position", return isl_bool_error);
825 for (i = 0; i < bmap->n_eq; ++i) {
826 if (isl_int_is_zero(bmap->eq[i][offset + pos]) ||
827 isl_seq_first_non_zero(bmap->eq[i]+offset+pos+1,
828 1+total-offset-pos-1) != -1)
829 continue;
830 if (c)
831 *c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
832 &bmap->eq[i]);
833 return isl_bool_true;
834 }
835 return isl_bool_false;
836 }
837
838 /* Is the variable of "type" at position "pos" of "bset" defined
839 * in terms of earlier dimensions through an equality?
840 *
841 * If so, and if c is not NULL, then return a copy of this equality in *c.
842 */
843 isl_bool isl_basic_set_has_defining_equality(
844 __isl_keep isl_basic_set *bset, enum isl_dim_type type, int pos,
845 __isl_give isl_constraint **c)
846 {
847 return isl_basic_map_has_defining_equality(bset_to_bmap(bset),
848 type, pos, c);
849 }
850
851 isl_bool isl_basic_set_has_defining_inequalities(
852 struct isl_basic_set *bset, enum isl_dim_type type, int pos,
853 struct isl_constraint **lower,
854 struct isl_constraint **upper)
855 {
856 int i, j;
857 unsigned offset;
858 unsigned total;
859 isl_int m;
860 isl_int **lower_line, **upper_line;
861
862 if (!bset)
863 return isl_bool_error;
864 offset = basic_set_offset(bset, type);
865 total = isl_basic_set_total_dim(bset);
866 if (pos >= isl_basic_set_dim(bset, type))
867 isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
868 "invalid position", return isl_bool_error);
869 isl_int_init(m);
870 for (i = 0; i < bset->n_ineq; ++i) {
871 if (isl_int_is_zero(bset->ineq[i][offset + pos]))
872 continue;
873 if (isl_int_is_one(bset->ineq[i][offset + pos]))
874 continue;
875 if (isl_int_is_negone(bset->ineq[i][offset + pos]))
876 continue;
877 if (isl_seq_first_non_zero(bset->ineq[i]+offset+pos+1,
878 1+total-offset-pos-1) != -1)
879 continue;
880 for (j = i + 1; j < bset->n_ineq; ++j) {
881 if (!isl_seq_is_neg(bset->ineq[i]+1, bset->ineq[j]+1,
882 total))
883 continue;
884 isl_int_add(m, bset->ineq[i][0], bset->ineq[j][0]);
885 if (isl_int_abs_ge(m, bset->ineq[i][offset+pos]))
886 continue;
887
888 if (isl_int_is_pos(bset->ineq[i][offset+pos])) {
889 lower_line = &bset->ineq[i];
890 upper_line = &bset->ineq[j];
891 } else {
892 lower_line = &bset->ineq[j];
893 upper_line = &bset->ineq[i];
894 }
895 *lower = isl_basic_set_constraint(
896 isl_basic_set_copy(bset), lower_line);
897 *upper = isl_basic_set_constraint(
898 isl_basic_set_copy(bset), upper_line);
899 isl_int_clear(m);
900 return isl_bool_true;
901 }
902 }
903 *lower = NULL;
904 *upper = NULL;
905 isl_int_clear(m);
906 return isl_bool_false;
907 }
908
909 /* Given two constraints "a" and "b" on the variable at position "abs_pos"
910 * (in "a" and "b"), add a constraint to "bset" that ensures that the
911 * bound implied by "a" is (strictly) larger than the bound implied by "b".
912 *
913 * If both constraints imply lower bounds, then this means that "a" is
914 * active in the result.
915 * If both constraints imply upper bounds, then this means that "b" is
916 * active in the result.
917 */
918 static __isl_give isl_basic_set *add_larger_bound_constraint(
919 __isl_take isl_basic_set *bset, isl_int *a, isl_int *b,
920 unsigned abs_pos, int strict)
921 {
922 int k;
923 isl_int t;
924 unsigned total;
925
926 k = isl_basic_set_alloc_inequality(bset);
927 if (k < 0)
928 goto error;
929
930 total = isl_basic_set_dim(bset, isl_dim_all);
931
932 isl_int_init(t);
933 isl_int_neg(t, b[1 + abs_pos]);
934
935 isl_seq_combine(bset->ineq[k], t, a, a[1 + abs_pos], b, 1 + abs_pos);
936 isl_seq_combine(bset->ineq[k] + 1 + abs_pos,
937 t, a + 1 + abs_pos + 1, a[1 + abs_pos], b + 1 + abs_pos + 1,
938 total - abs_pos);
939
940 if (strict)
941 isl_int_sub_ui(bset->ineq[k][0], bset->ineq[k][0], 1);
942
943 isl_int_clear(t);
944
945 return bset;
946 error:
947 isl_basic_set_free(bset);
948 return NULL;
949 }
950
951 /* Add constraints to "context" that ensure that "u" is the smallest
952 * (and therefore active) upper bound on "abs_pos" in "bset" and return
953 * the resulting basic set.
954 */
955 static __isl_give isl_basic_set *set_smallest_upper_bound(
956 __isl_keep isl_basic_set *context,
957 __isl_keep isl_basic_set *bset, unsigned abs_pos, int n_upper, int u)
958 {
959 int j;
960
961 context = isl_basic_set_copy(context);
962 context = isl_basic_set_cow(context);
963
964 context = isl_basic_set_extend_constraints(context, 0, n_upper - 1);
965
966 for (j = 0; j < bset->n_ineq; ++j) {
967 if (j == u)
968 continue;
969 if (!isl_int_is_neg(bset->ineq[j][1 + abs_pos]))
970 continue;
971 context = add_larger_bound_constraint(context,
972 bset->ineq[j], bset->ineq[u], abs_pos, j > u);
973 }
974
975 context = isl_basic_set_simplify(context);
976 context = isl_basic_set_finalize(context);
977
978 return context;
979 }
980
981 /* Add constraints to "context" that ensure that "u" is the largest
982 * (and therefore active) upper bound on "abs_pos" in "bset" and return
983 * the resulting basic set.
984 */
985 static __isl_give isl_basic_set *set_largest_lower_bound(
986 __isl_keep isl_basic_set *context,
987 __isl_keep isl_basic_set *bset, unsigned abs_pos, int n_lower, int l)
988 {
989 int j;
990
991 context = isl_basic_set_copy(context);
992 context = isl_basic_set_cow(context);
993
994 context = isl_basic_set_extend_constraints(context, 0, n_lower - 1);
995
996 for (j = 0; j < bset->n_ineq; ++j) {
997 if (j == l)
998 continue;
999 if (!isl_int_is_pos(bset->ineq[j][1 + abs_pos]))
1000 continue;
1001 context = add_larger_bound_constraint(context,
1002 bset->ineq[l], bset->ineq[j], abs_pos, j > l);
1003 }
1004
1005 context = isl_basic_set_simplify(context);
1006 context = isl_basic_set_finalize(context);
1007
1008 return context;
1009 }
1010
1011 static isl_stat foreach_upper_bound(__isl_keep isl_basic_set *bset,
1012 enum isl_dim_type type, unsigned abs_pos,
1013 __isl_take isl_basic_set *context, int n_upper,
1014 isl_stat (*fn)(__isl_take isl_constraint *lower,
1015 __isl_take isl_constraint *upper,
1016 __isl_take isl_basic_set *bset, void *user), void *user)
1017 {
1018 isl_basic_set *context_i;
1019 isl_constraint *upper = NULL;
1020 int i;
1021
1022 for (i = 0; i < bset->n_ineq; ++i) {
1023 if (isl_int_is_zero(bset->ineq[i][1 + abs_pos]))
1024 continue;
1025
1026 context_i = set_smallest_upper_bound(context, bset,
1027 abs_pos, n_upper, i);
1028 if (isl_basic_set_is_empty(context_i)) {
1029 isl_basic_set_free(context_i);
1030 continue;
1031 }
1032 upper = isl_basic_set_constraint(isl_basic_set_copy(bset),
1033 &bset->ineq[i]);
1034 if (!upper || !context_i)
1035 goto error;
1036 if (fn(NULL, upper, context_i, user) < 0)
1037 break;
1038 }
1039
1040 isl_basic_set_free(context);
1041
1042 if (i < bset->n_ineq)
1043 return isl_stat_error;
1044
1045 return isl_stat_ok;
1046 error:
1047 isl_constraint_free(upper);
1048 isl_basic_set_free(context_i);
1049 isl_basic_set_free(context);
1050 return isl_stat_error;
1051 }
1052
1053 static isl_stat foreach_lower_bound(__isl_keep isl_basic_set *bset,
1054 enum isl_dim_type type, unsigned abs_pos,
1055 __isl_take isl_basic_set *context, int n_lower,
1056 isl_stat (*fn)(__isl_take isl_constraint *lower,
1057 __isl_take isl_constraint *upper,
1058 __isl_take isl_basic_set *bset, void *user), void *user)
1059 {
1060 isl_basic_set *context_i;
1061 isl_constraint *lower = NULL;
1062 int i;
1063
1064 for (i = 0; i < bset->n_ineq; ++i) {
1065 if (isl_int_is_zero(bset->ineq[i][1 + abs_pos]))
1066 continue;
1067
1068 context_i = set_largest_lower_bound(context, bset,
1069 abs_pos, n_lower, i);
1070 if (isl_basic_set_is_empty(context_i)) {
1071 isl_basic_set_free(context_i);
1072 continue;
1073 }
1074 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1075 &bset->ineq[i]);
1076 if (!lower || !context_i)
1077 goto error;
1078 if (fn(lower, NULL, context_i, user) < 0)
1079 break;
1080 }
1081
1082 isl_basic_set_free(context);
1083
1084 if (i < bset->n_ineq)
1085 return isl_stat_error;
1086
1087 return isl_stat_ok;
1088 error:
1089 isl_constraint_free(lower);
1090 isl_basic_set_free(context_i);
1091 isl_basic_set_free(context);
1092 return isl_stat_error;
1093 }
1094
1095 static isl_stat foreach_bound_pair(__isl_keep isl_basic_set *bset,
1096 enum isl_dim_type type, unsigned abs_pos,
1097 __isl_take isl_basic_set *context, int n_lower, int n_upper,
1098 isl_stat (*fn)(__isl_take isl_constraint *lower,
1099 __isl_take isl_constraint *upper,
1100 __isl_take isl_basic_set *bset, void *user), void *user)
1101 {
1102 isl_basic_set *context_i, *context_j;
1103 isl_constraint *lower = NULL;
1104 isl_constraint *upper = NULL;
1105 int i, j;
1106
1107 for (i = 0; i < bset->n_ineq; ++i) {
1108 if (!isl_int_is_pos(bset->ineq[i][1 + abs_pos]))
1109 continue;
1110
1111 context_i = set_largest_lower_bound(context, bset,
1112 abs_pos, n_lower, i);
1113 if (isl_basic_set_is_empty(context_i)) {
1114 isl_basic_set_free(context_i);
1115 continue;
1116 }
1117
1118 for (j = 0; j < bset->n_ineq; ++j) {
1119 if (!isl_int_is_neg(bset->ineq[j][1 + abs_pos]))
1120 continue;
1121
1122 context_j = set_smallest_upper_bound(context_i, bset,
1123 abs_pos, n_upper, j);
1124 context_j = isl_basic_set_extend_constraints(context_j,
1125 0, 1);
1126 context_j = add_larger_bound_constraint(context_j,
1127 bset->ineq[i], bset->ineq[j], abs_pos, 0);
1128 context_j = isl_basic_set_simplify(context_j);
1129 context_j = isl_basic_set_finalize(context_j);
1130 if (isl_basic_set_is_empty(context_j)) {
1131 isl_basic_set_free(context_j);
1132 continue;
1133 }
1134 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1135 &bset->ineq[i]);
1136 upper = isl_basic_set_constraint(isl_basic_set_copy(bset),
1137 &bset->ineq[j]);
1138 if (!lower || !upper || !context_j)
1139 goto error;
1140 if (fn(lower, upper, context_j, user) < 0)
1141 break;
1142 }
1143
1144 isl_basic_set_free(context_i);
1145
1146 if (j < bset->n_ineq)
1147 break;
1148 }
1149
1150 isl_basic_set_free(context);
1151
1152 if (i < bset->n_ineq)
1153 return isl_stat_error;
1154
1155 return isl_stat_ok;
1156 error:
1157 isl_constraint_free(lower);
1158 isl_constraint_free(upper);
1159 isl_basic_set_free(context_i);
1160 isl_basic_set_free(context_j);
1161 isl_basic_set_free(context);
1162 return isl_stat_error;
1163 }
1164
1165 /* For each pair of lower and upper bounds on the variable "pos"
1166 * of type "type", call "fn" with these lower and upper bounds and the
1167 * set of constraints on the remaining variables where these bounds
1168 * are active, i.e., (stricly) larger/smaller than the other lower/upper bounds.
1169 *
1170 * If the designated variable is equal to an affine combination of the
1171 * other variables then fn is called with both lower and upper
1172 * set to the corresponding equality.
1173 *
1174 * If there is no lower (or upper) bound, then NULL is passed
1175 * as the corresponding bound.
1176 *
1177 * We first check if the variable is involved in any equality.
1178 * If not, we count the number of lower and upper bounds and
1179 * act accordingly.
1180 */
1181 isl_stat isl_basic_set_foreach_bound_pair(__isl_keep isl_basic_set *bset,
1182 enum isl_dim_type type, unsigned pos,
1183 isl_stat (*fn)(__isl_take isl_constraint *lower,
1184 __isl_take isl_constraint *upper,
1185 __isl_take isl_basic_set *bset, void *user), void *user)
1186 {
1187 int i;
1188 isl_constraint *lower = NULL;
1189 isl_constraint *upper = NULL;
1190 isl_basic_set *context = NULL;
1191 unsigned abs_pos;
1192 int n_lower, n_upper;
1193
1194 if (!bset)
1195 return isl_stat_error;
1196 isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type),
1197 return isl_stat_error);
1198 isl_assert(bset->ctx, type == isl_dim_param || type == isl_dim_set,
1199 return isl_stat_error);
1200
1201 abs_pos = pos;
1202 if (type == isl_dim_set)
1203 abs_pos += isl_basic_set_dim(bset, isl_dim_param);
1204
1205 for (i = 0; i < bset->n_eq; ++i) {
1206 if (isl_int_is_zero(bset->eq[i][1 + abs_pos]))
1207 continue;
1208
1209 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1210 &bset->eq[i]);
1211 upper = isl_constraint_copy(lower);
1212 context = isl_basic_set_remove_dims(isl_basic_set_copy(bset),
1213 type, pos, 1);
1214 if (!lower || !upper || !context)
1215 goto error;
1216 return fn(lower, upper, context, user);
1217 }
1218
1219 n_lower = 0;
1220 n_upper = 0;
1221 for (i = 0; i < bset->n_ineq; ++i) {
1222 if (isl_int_is_pos(bset->ineq[i][1 + abs_pos]))
1223 n_lower++;
1224 else if (isl_int_is_neg(bset->ineq[i][1 + abs_pos]))
1225 n_upper++;
1226 }
1227
1228 context = isl_basic_set_copy(bset);
1229 context = isl_basic_set_cow(context);
1230 if (!context)
1231 goto error;
1232 for (i = context->n_ineq - 1; i >= 0; --i)
1233 if (!isl_int_is_zero(context->ineq[i][1 + abs_pos]))
1234 isl_basic_set_drop_inequality(context, i);
1235
1236 context = isl_basic_set_drop(context, type, pos, 1);
1237 if (!n_lower && !n_upper)
1238 return fn(NULL, NULL, context, user);
1239 if (!n_lower)
1240 return foreach_upper_bound(bset, type, abs_pos, context, n_upper,
1241 fn, user);
1242 if (!n_upper)
1243 return foreach_lower_bound(bset, type, abs_pos, context, n_lower,
1244 fn, user);
1245 return foreach_bound_pair(bset, type, abs_pos, context, n_lower, n_upper,
1246 fn, user);
1247 error:
1248 isl_constraint_free(lower);
1249 isl_constraint_free(upper);
1250 isl_basic_set_free(context);
1251 return -1;
1252 }
1253
1254 __isl_give isl_aff *isl_constraint_get_bound(
1255 __isl_keep isl_constraint *constraint, enum isl_dim_type type, int pos)
1256 {
1257 isl_aff *aff;
1258 isl_ctx *ctx;
1259
1260 if (!constraint)
1261 return NULL;
1262 ctx = isl_constraint_get_ctx(constraint);
1263 if (pos >= isl_constraint_dim(constraint, type))
1264 isl_die(ctx, isl_error_invalid,
1265 "index out of bounds", return NULL);
1266 if (isl_constraint_dim(constraint, isl_dim_in) != 0)
1267 isl_die(ctx, isl_error_invalid,
1268 "not a set constraint", return NULL);
1269
1270 pos += offset(constraint, type);
1271 if (isl_int_is_zero(constraint->v->el[pos]))
1272 isl_die(ctx, isl_error_invalid,
1273 "constraint does not define a bound on given dimension",
1274 return NULL);
1275
1276 aff = isl_aff_alloc(isl_local_space_copy(constraint->ls));
1277 if (!aff)
1278 return NULL;
1279
1280 if (isl_int_is_neg(constraint->v->el[pos]))
1281 isl_seq_cpy(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1282 else
1283 isl_seq_neg(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1284 isl_int_set_si(aff->v->el[1 + pos], 0);
1285 isl_int_abs(aff->v->el[0], constraint->v->el[pos]);
1286
1287 return aff;
1288 }
1289
1290 /* For an inequality constraint
1291 *
1292 * f >= 0
1293 *
1294 * or an equality constraint
1295 *
1296 * f = 0
1297 *
1298 * return the affine expression f.
1299 */
1300 __isl_give isl_aff *isl_constraint_get_aff(
1301 __isl_keep isl_constraint *constraint)
1302 {
1303 isl_aff *aff;
1304
1305 if (!constraint)
1306 return NULL;
1307
1308 aff = isl_aff_alloc(isl_local_space_copy(constraint->ls));
1309 if (!aff)
1310 return NULL;
1311
1312 isl_seq_cpy(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1313 isl_int_set_si(aff->v->el[0], 1);
1314
1315 return aff;
1316 }
1317
1318 /* Construct an inequality (eq = 0) or equality (eq = 1) constraint from "aff".
1319 * In particular, construct aff >= 0 or aff = 0.
1320 *
1321 * The denominator of "aff" can be ignored.
1322 */
1323 static __isl_give isl_constraint *isl_constraint_alloc_aff(int eq,
1324 __isl_take isl_aff *aff)
1325 {
1326 isl_local_space *ls;
1327 isl_vec *v;
1328
1329 if (!aff)
1330 return NULL;
1331 ls = isl_aff_get_domain_local_space(aff);
1332 v = isl_vec_drop_els(isl_vec_copy(aff->v), 0, 1);
1333 isl_aff_free(aff);
1334
1335 return isl_constraint_alloc_vec(eq, ls, v);
1336 }
1337
1338 /* Construct an equality constraint equating the given affine expression
1339 * to zero.
1340 */
1341 __isl_give isl_constraint *isl_equality_from_aff(__isl_take isl_aff *aff)
1342 {
1343 return isl_constraint_alloc_aff(1, aff);
1344 }
1345
1346 /* Construct an inequality constraint enforcing the given affine expression
1347 * to be non-negative.
1348 */
1349 __isl_give isl_constraint *isl_inequality_from_aff(__isl_take isl_aff *aff)
1350 {
1351 return isl_constraint_alloc_aff(0, aff);
1352 }
1353
1354 /* Compare two isl_constraints.
1355 *
1356 * Return -1 if "c1" is "smaller" than "c2", 1 if "c1" is "greater"
1357 * than "c2" and 0 if they are equal.
1358 *
1359 * The order is fairly arbitrary. We do consider constraints that only involve
1360 * earlier dimensions as "smaller".
1361 */
1362 int isl_constraint_plain_cmp(__isl_keep isl_constraint *c1,
1363 __isl_keep isl_constraint *c2)
1364 {
1365 int cmp;
1366 int last1, last2;
1367
1368 if (c1 == c2)
1369 return 0;
1370 if (!c1)
1371 return -1;
1372 if (!c2)
1373 return 1;
1374 cmp = isl_local_space_cmp(c1->ls, c2->ls);
1375 if (cmp != 0)
1376 return cmp;
1377
1378 last1 = isl_seq_last_non_zero(c1->v->el + 1, c1->v->size - 1);
1379 last2 = isl_seq_last_non_zero(c2->v->el + 1, c1->v->size - 1);
1380 if (last1 != last2)
1381 return last1 - last2;
1382
1383 return isl_seq_cmp(c1->v->el, c2->v->el, c1->v->size);
1384 }
1385
1386 /* Compare two constraints based on their final (non-zero) coefficients.
1387 * In particular, the constraint that involves later variables or
1388 * that has a larger coefficient for a shared latest variable
1389 * is considered "greater" than the other constraint.
1390 *
1391 * Return -1 if "c1" is "smaller" than "c2", 1 if "c1" is "greater"
1392 * than "c2" and 0 if they are equal.
1393 *
1394 * If the constraints live in different local spaces, then we cannot
1395 * really compare the constraints so we compare the local spaces instead.
1396 */
1397 int isl_constraint_cmp_last_non_zero(__isl_keep isl_constraint *c1,
1398 __isl_keep isl_constraint *c2)
1399 {
1400 int cmp;
1401 int last1, last2;
1402
1403 if (c1 == c2)
1404 return 0;
1405 if (!c1)
1406 return -1;
1407 if (!c2)
1408 return 1;
1409 cmp = isl_local_space_cmp(c1->ls, c2->ls);
1410 if (cmp != 0)
1411 return cmp;
1412
1413 last1 = isl_seq_last_non_zero(c1->v->el + 1, c1->v->size - 1);
1414 last2 = isl_seq_last_non_zero(c2->v->el + 1, c1->v->size - 1);
1415 if (last1 != last2)
1416 return last1 - last2;
1417 if (last1 == -1)
1418 return 0;
1419 return isl_int_abs_cmp(c1->v->el[1 + last1], c2->v->el[1 + last2]);
1420 }
Integer set library