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isl_output.c: print_omega_parameters: rename "dim" argument to "space"
[isl.git] / isl_constraint.c
blob114631255245dd3e9223284211c1ff34784d4c74
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(__isl_keep 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->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->v = isl_vec_cow(constraint->v);
655 if (!constraint->v)
656 return isl_constraint_free(constraint);
657
658 pos += isl_local_space_offset(constraint->ls, type);
659 isl_int_set_si(constraint->v->el[pos], v);
660
661 return constraint;
662 }
663
664 struct isl_constraint *isl_constraint_negate(struct isl_constraint *constraint)
665 {
666 isl_ctx *ctx;
667
668 constraint = isl_constraint_cow(constraint);
669 if (!constraint)
670 return NULL;
671
672 ctx = isl_constraint_get_ctx(constraint);
673 if (isl_constraint_is_equality(constraint))
674 isl_die(ctx, isl_error_invalid, "cannot negate equality",
675 return isl_constraint_free(constraint));
676 constraint->v = isl_vec_neg(constraint->v);
677 constraint->v = isl_vec_cow(constraint->v);
678 if (!constraint->v)
679 return isl_constraint_free(constraint);
680 isl_int_sub_ui(constraint->v->el[0], constraint->v->el[0], 1);
681 return constraint;
682 }
683
684 isl_bool isl_constraint_is_equality(struct isl_constraint *constraint)
685 {
686 if (!constraint)
687 return isl_bool_error;
688 return constraint->eq;
689 }
690
691 int isl_constraint_is_div_constraint(__isl_keep isl_constraint *constraint)
692 {
693 int i;
694 int n_div;
695
696 if (!constraint)
697 return -1;
698 if (isl_constraint_is_equality(constraint))
699 return 0;
700 n_div = isl_constraint_dim(constraint, isl_dim_div);
701 for (i = 0; i < n_div; ++i) {
702 isl_bool is_div;
703 is_div = isl_local_space_is_div_constraint(constraint->ls,
704 constraint->v->el, i);
705 if (is_div < 0 || is_div)
706 return is_div;
707 }
708
709 return 0;
710 }
711
712 /* Is "constraint" an equality that corresponds to integer division "div"?
713 *
714 * That is, given an integer division of the form
715 *
716 * a = floor((f + c)/m)
717 *
718 * is the equality of the form
719 *
720 * -f + m d + c' = 0
721 * ?
722 * Note that the constant term is not checked explicitly, but given
723 * that this is a valid equality constraint, the constant c' necessarily
724 * has a value close to -c.
725 */
726 isl_bool isl_constraint_is_div_equality(__isl_keep isl_constraint *constraint,
727 unsigned div)
728 {
729 isl_bool equality;
730
731 equality = isl_constraint_is_equality(constraint);
732 if (equality < 0 || !equality)
733 return equality;
734 return isl_local_space_is_div_equality(constraint->ls,
735 constraint->v->el, div);
736 }
737
738 /* We manually set ISL_BASIC_SET_FINAL instead of calling
739 * isl_basic_map_finalize because we want to keep the position
740 * of the divs and we therefore do not want to throw away redundant divs.
741 * This is arguably a bit fragile.
742 */
743 __isl_give isl_basic_map *isl_basic_map_from_constraint(
744 __isl_take isl_constraint *constraint)
745 {
746 int k;
747 isl_local_space *ls;
748 struct isl_basic_map *bmap;
749 isl_int *c;
750 unsigned total;
751
752 if (!constraint)
753 return NULL;
754
755 ls = isl_local_space_copy(constraint->ls);
756 bmap = isl_basic_map_from_local_space(ls);
757 bmap = isl_basic_map_extend_constraints(bmap, 1, 1);
758 if (isl_constraint_is_equality(constraint)) {
759 k = isl_basic_map_alloc_equality(bmap);
760 if (k < 0)
761 goto error;
762 c = bmap->eq[k];
763 }
764 else {
765 k = isl_basic_map_alloc_inequality(bmap);
766 if (k < 0)
767 goto error;
768 c = bmap->ineq[k];
769 }
770 total = isl_basic_map_total_dim(bmap);
771 isl_seq_cpy(c, constraint->v->el, 1 + total);
772 isl_constraint_free(constraint);
773 if (bmap)
774 ISL_F_SET(bmap, ISL_BASIC_SET_FINAL);
775 return bmap;
776 error:
777 isl_constraint_free(constraint);
778 isl_basic_map_free(bmap);
779 return NULL;
780 }
781
782 __isl_give isl_basic_set *isl_basic_set_from_constraint(
783 __isl_take isl_constraint *constraint)
784 {
785 if (!constraint)
786 return NULL;
787
788 if (isl_constraint_dim(constraint, isl_dim_in) != 0)
789 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
790 "not a set constraint", goto error);
791 return bset_from_bmap(isl_basic_map_from_constraint(constraint));
792 error:
793 isl_constraint_free(constraint);
794 return NULL;
795 }
796
797 /* Is the variable of "type" at position "pos" of "bmap" defined
798 * in terms of earlier dimensions through an equality?
799 *
800 * If so, and if c is not NULL, then return a copy of this equality in *c.
801 */
802 isl_bool isl_basic_map_has_defining_equality(
803 __isl_keep isl_basic_map *bmap, enum isl_dim_type type, int pos,
804 __isl_give isl_constraint **c)
805 {
806 int i;
807 unsigned offset;
808 unsigned total;
809
810 if (!bmap)
811 return isl_bool_error;
812 offset = basic_map_offset(bmap, type);
813 total = isl_basic_map_total_dim(bmap);
814 if (pos >= isl_basic_map_dim(bmap, type))
815 isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
816 "invalid position", return isl_bool_error);
817 for (i = 0; i < bmap->n_eq; ++i) {
818 if (isl_int_is_zero(bmap->eq[i][offset + pos]) ||
819 isl_seq_first_non_zero(bmap->eq[i]+offset+pos+1,
820 1+total-offset-pos-1) != -1)
821 continue;
822 if (c)
823 *c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
824 &bmap->eq[i]);
825 return isl_bool_true;
826 }
827 return isl_bool_false;
828 }
829
830 /* Is the variable of "type" at position "pos" of "bset" defined
831 * in terms of earlier dimensions through an equality?
832 *
833 * If so, and if c is not NULL, then return a copy of this equality in *c.
834 */
835 isl_bool isl_basic_set_has_defining_equality(
836 __isl_keep isl_basic_set *bset, enum isl_dim_type type, int pos,
837 __isl_give isl_constraint **c)
838 {
839 return isl_basic_map_has_defining_equality(bset_to_bmap(bset),
840 type, pos, c);
841 }
842
843 isl_bool isl_basic_set_has_defining_inequalities(
844 struct isl_basic_set *bset, enum isl_dim_type type, int pos,
845 struct isl_constraint **lower,
846 struct isl_constraint **upper)
847 {
848 int i, j;
849 unsigned offset;
850 unsigned total;
851 isl_int m;
852 isl_int **lower_line, **upper_line;
853
854 if (!bset)
855 return isl_bool_error;
856 offset = basic_set_offset(bset, type);
857 total = isl_basic_set_total_dim(bset);
858 if (pos >= isl_basic_set_dim(bset, type))
859 isl_die(isl_basic_set_get_ctx(bset), isl_error_invalid,
860 "invalid position", return isl_bool_error);
861 isl_int_init(m);
862 for (i = 0; i < bset->n_ineq; ++i) {
863 if (isl_int_is_zero(bset->ineq[i][offset + pos]))
864 continue;
865 if (isl_int_is_one(bset->ineq[i][offset + pos]))
866 continue;
867 if (isl_int_is_negone(bset->ineq[i][offset + pos]))
868 continue;
869 if (isl_seq_first_non_zero(bset->ineq[i]+offset+pos+1,
870 1+total-offset-pos-1) != -1)
871 continue;
872 for (j = i + 1; j < bset->n_ineq; ++j) {
873 if (!isl_seq_is_neg(bset->ineq[i]+1, bset->ineq[j]+1,
874 total))
875 continue;
876 isl_int_add(m, bset->ineq[i][0], bset->ineq[j][0]);
877 if (isl_int_abs_ge(m, bset->ineq[i][offset+pos]))
878 continue;
879
880 if (isl_int_is_pos(bset->ineq[i][offset+pos])) {
881 lower_line = &bset->ineq[i];
882 upper_line = &bset->ineq[j];
883 } else {
884 lower_line = &bset->ineq[j];
885 upper_line = &bset->ineq[i];
886 }
887 *lower = isl_basic_set_constraint(
888 isl_basic_set_copy(bset), lower_line);
889 *upper = isl_basic_set_constraint(
890 isl_basic_set_copy(bset), upper_line);
891 isl_int_clear(m);
892 return isl_bool_true;
893 }
894 }
895 *lower = NULL;
896 *upper = NULL;
897 isl_int_clear(m);
898 return isl_bool_false;
899 }
900
901 /* Given two constraints "a" and "b" on the variable at position "abs_pos"
902 * (in "a" and "b"), add a constraint to "bset" that ensures that the
903 * bound implied by "a" is (strictly) larger than the bound implied by "b".
904 *
905 * If both constraints imply lower bounds, then this means that "a" is
906 * active in the result.
907 * If both constraints imply upper bounds, then this means that "b" is
908 * active in the result.
909 */
910 static __isl_give isl_basic_set *add_larger_bound_constraint(
911 __isl_take isl_basic_set *bset, isl_int *a, isl_int *b,
912 unsigned abs_pos, int strict)
913 {
914 int k;
915 isl_int t;
916 unsigned total;
917
918 k = isl_basic_set_alloc_inequality(bset);
919 if (k < 0)
920 goto error;
921
922 total = isl_basic_set_dim(bset, isl_dim_all);
923
924 isl_int_init(t);
925 isl_int_neg(t, b[1 + abs_pos]);
926
927 isl_seq_combine(bset->ineq[k], t, a, a[1 + abs_pos], b, 1 + abs_pos);
928 isl_seq_combine(bset->ineq[k] + 1 + abs_pos,
929 t, a + 1 + abs_pos + 1, a[1 + abs_pos], b + 1 + abs_pos + 1,
930 total - abs_pos);
931
932 if (strict)
933 isl_int_sub_ui(bset->ineq[k][0], bset->ineq[k][0], 1);
934
935 isl_int_clear(t);
936
937 return bset;
938 error:
939 isl_basic_set_free(bset);
940 return NULL;
941 }
942
943 /* Add constraints to "context" that ensure that "u" is the smallest
944 * (and therefore active) upper bound on "abs_pos" in "bset" and return
945 * the resulting basic set.
946 */
947 static __isl_give isl_basic_set *set_smallest_upper_bound(
948 __isl_keep isl_basic_set *context,
949 __isl_keep isl_basic_set *bset, unsigned abs_pos, int n_upper, int u)
950 {
951 int j;
952
953 context = isl_basic_set_copy(context);
954 context = isl_basic_set_cow(context);
955
956 context = isl_basic_set_extend_constraints(context, 0, n_upper - 1);
957
958 for (j = 0; j < bset->n_ineq; ++j) {
959 if (j == u)
960 continue;
961 if (!isl_int_is_neg(bset->ineq[j][1 + abs_pos]))
962 continue;
963 context = add_larger_bound_constraint(context,
964 bset->ineq[j], bset->ineq[u], abs_pos, j > u);
965 }
966
967 context = isl_basic_set_simplify(context);
968 context = isl_basic_set_finalize(context);
969
970 return context;
971 }
972
973 /* Add constraints to "context" that ensure that "u" is the largest
974 * (and therefore active) upper bound on "abs_pos" in "bset" and return
975 * the resulting basic set.
976 */
977 static __isl_give isl_basic_set *set_largest_lower_bound(
978 __isl_keep isl_basic_set *context,
979 __isl_keep isl_basic_set *bset, unsigned abs_pos, int n_lower, int l)
980 {
981 int j;
982
983 context = isl_basic_set_copy(context);
984 context = isl_basic_set_cow(context);
985
986 context = isl_basic_set_extend_constraints(context, 0, n_lower - 1);
987
988 for (j = 0; j < bset->n_ineq; ++j) {
989 if (j == l)
990 continue;
991 if (!isl_int_is_pos(bset->ineq[j][1 + abs_pos]))
992 continue;
993 context = add_larger_bound_constraint(context,
994 bset->ineq[l], bset->ineq[j], abs_pos, j > l);
995 }
996
997 context = isl_basic_set_simplify(context);
998 context = isl_basic_set_finalize(context);
999
1000 return context;
1001 }
1002
1003 static isl_stat foreach_upper_bound(__isl_keep isl_basic_set *bset,
1004 enum isl_dim_type type, unsigned abs_pos,
1005 __isl_take isl_basic_set *context, int n_upper,
1006 isl_stat (*fn)(__isl_take isl_constraint *lower,
1007 __isl_take isl_constraint *upper,
1008 __isl_take isl_basic_set *bset, void *user), void *user)
1009 {
1010 isl_basic_set *context_i;
1011 isl_constraint *upper = NULL;
1012 int i;
1013
1014 for (i = 0; i < bset->n_ineq; ++i) {
1015 if (isl_int_is_zero(bset->ineq[i][1 + abs_pos]))
1016 continue;
1017
1018 context_i = set_smallest_upper_bound(context, bset,
1019 abs_pos, n_upper, i);
1020 if (isl_basic_set_is_empty(context_i)) {
1021 isl_basic_set_free(context_i);
1022 continue;
1023 }
1024 upper = isl_basic_set_constraint(isl_basic_set_copy(bset),
1025 &bset->ineq[i]);
1026 if (!upper || !context_i)
1027 goto error;
1028 if (fn(NULL, upper, context_i, user) < 0)
1029 break;
1030 }
1031
1032 isl_basic_set_free(context);
1033
1034 if (i < bset->n_ineq)
1035 return isl_stat_error;
1036
1037 return isl_stat_ok;
1038 error:
1039 isl_constraint_free(upper);
1040 isl_basic_set_free(context_i);
1041 isl_basic_set_free(context);
1042 return isl_stat_error;
1043 }
1044
1045 static isl_stat foreach_lower_bound(__isl_keep isl_basic_set *bset,
1046 enum isl_dim_type type, unsigned abs_pos,
1047 __isl_take isl_basic_set *context, int n_lower,
1048 isl_stat (*fn)(__isl_take isl_constraint *lower,
1049 __isl_take isl_constraint *upper,
1050 __isl_take isl_basic_set *bset, void *user), void *user)
1051 {
1052 isl_basic_set *context_i;
1053 isl_constraint *lower = NULL;
1054 int i;
1055
1056 for (i = 0; i < bset->n_ineq; ++i) {
1057 if (isl_int_is_zero(bset->ineq[i][1 + abs_pos]))
1058 continue;
1059
1060 context_i = set_largest_lower_bound(context, bset,
1061 abs_pos, n_lower, i);
1062 if (isl_basic_set_is_empty(context_i)) {
1063 isl_basic_set_free(context_i);
1064 continue;
1065 }
1066 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1067 &bset->ineq[i]);
1068 if (!lower || !context_i)
1069 goto error;
1070 if (fn(lower, NULL, context_i, user) < 0)
1071 break;
1072 }
1073
1074 isl_basic_set_free(context);
1075
1076 if (i < bset->n_ineq)
1077 return isl_stat_error;
1078
1079 return isl_stat_ok;
1080 error:
1081 isl_constraint_free(lower);
1082 isl_basic_set_free(context_i);
1083 isl_basic_set_free(context);
1084 return isl_stat_error;
1085 }
1086
1087 static isl_stat foreach_bound_pair(__isl_keep isl_basic_set *bset,
1088 enum isl_dim_type type, unsigned abs_pos,
1089 __isl_take isl_basic_set *context, int n_lower, int n_upper,
1090 isl_stat (*fn)(__isl_take isl_constraint *lower,
1091 __isl_take isl_constraint *upper,
1092 __isl_take isl_basic_set *bset, void *user), void *user)
1093 {
1094 isl_basic_set *context_i, *context_j;
1095 isl_constraint *lower = NULL;
1096 isl_constraint *upper = NULL;
1097 int i, j;
1098
1099 for (i = 0; i < bset->n_ineq; ++i) {
1100 if (!isl_int_is_pos(bset->ineq[i][1 + abs_pos]))
1101 continue;
1102
1103 context_i = set_largest_lower_bound(context, bset,
1104 abs_pos, n_lower, i);
1105 if (isl_basic_set_is_empty(context_i)) {
1106 isl_basic_set_free(context_i);
1107 continue;
1108 }
1109
1110 for (j = 0; j < bset->n_ineq; ++j) {
1111 if (!isl_int_is_neg(bset->ineq[j][1 + abs_pos]))
1112 continue;
1113
1114 context_j = set_smallest_upper_bound(context_i, bset,
1115 abs_pos, n_upper, j);
1116 context_j = isl_basic_set_extend_constraints(context_j,
1117 0, 1);
1118 context_j = add_larger_bound_constraint(context_j,
1119 bset->ineq[i], bset->ineq[j], abs_pos, 0);
1120 context_j = isl_basic_set_simplify(context_j);
1121 context_j = isl_basic_set_finalize(context_j);
1122 if (isl_basic_set_is_empty(context_j)) {
1123 isl_basic_set_free(context_j);
1124 continue;
1125 }
1126 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1127 &bset->ineq[i]);
1128 upper = isl_basic_set_constraint(isl_basic_set_copy(bset),
1129 &bset->ineq[j]);
1130 if (!lower || !upper || !context_j)
1131 goto error;
1132 if (fn(lower, upper, context_j, user) < 0)
1133 break;
1134 }
1135
1136 isl_basic_set_free(context_i);
1137
1138 if (j < bset->n_ineq)
1139 break;
1140 }
1141
1142 isl_basic_set_free(context);
1143
1144 if (i < bset->n_ineq)
1145 return isl_stat_error;
1146
1147 return isl_stat_ok;
1148 error:
1149 isl_constraint_free(lower);
1150 isl_constraint_free(upper);
1151 isl_basic_set_free(context_i);
1152 isl_basic_set_free(context_j);
1153 isl_basic_set_free(context);
1154 return isl_stat_error;
1155 }
1156
1157 /* For each pair of lower and upper bounds on the variable "pos"
1158 * of type "type", call "fn" with these lower and upper bounds and the
1159 * set of constraints on the remaining variables where these bounds
1160 * are active, i.e., (stricly) larger/smaller than the other lower/upper bounds.
1161 *
1162 * If the designated variable is equal to an affine combination of the
1163 * other variables then fn is called with both lower and upper
1164 * set to the corresponding equality.
1165 *
1166 * If there is no lower (or upper) bound, then NULL is passed
1167 * as the corresponding bound.
1168 *
1169 * We first check if the variable is involved in any equality.
1170 * If not, we count the number of lower and upper bounds and
1171 * act accordingly.
1172 */
1173 isl_stat isl_basic_set_foreach_bound_pair(__isl_keep isl_basic_set *bset,
1174 enum isl_dim_type type, unsigned pos,
1175 isl_stat (*fn)(__isl_take isl_constraint *lower,
1176 __isl_take isl_constraint *upper,
1177 __isl_take isl_basic_set *bset, void *user), void *user)
1178 {
1179 int i;
1180 isl_constraint *lower = NULL;
1181 isl_constraint *upper = NULL;
1182 isl_basic_set *context = NULL;
1183 unsigned abs_pos;
1184 int n_lower, n_upper;
1185
1186 if (!bset)
1187 return isl_stat_error;
1188 isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type),
1189 return isl_stat_error);
1190 isl_assert(bset->ctx, type == isl_dim_param || type == isl_dim_set,
1191 return isl_stat_error);
1192
1193 abs_pos = pos;
1194 if (type == isl_dim_set)
1195 abs_pos += isl_basic_set_dim(bset, isl_dim_param);
1196
1197 for (i = 0; i < bset->n_eq; ++i) {
1198 if (isl_int_is_zero(bset->eq[i][1 + abs_pos]))
1199 continue;
1200
1201 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1202 &bset->eq[i]);
1203 upper = isl_constraint_copy(lower);
1204 context = isl_basic_set_remove_dims(isl_basic_set_copy(bset),
1205 type, pos, 1);
1206 if (!lower || !upper || !context)
1207 goto error;
1208 return fn(lower, upper, context, user);
1209 }
1210
1211 n_lower = 0;
1212 n_upper = 0;
1213 for (i = 0; i < bset->n_ineq; ++i) {
1214 if (isl_int_is_pos(bset->ineq[i][1 + abs_pos]))
1215 n_lower++;
1216 else if (isl_int_is_neg(bset->ineq[i][1 + abs_pos]))
1217 n_upper++;
1218 }
1219
1220 context = isl_basic_set_copy(bset);
1221 context = isl_basic_set_cow(context);
1222 if (!context)
1223 goto error;
1224 for (i = context->n_ineq - 1; i >= 0; --i)
1225 if (!isl_int_is_zero(context->ineq[i][1 + abs_pos]))
1226 isl_basic_set_drop_inequality(context, i);
1227
1228 context = isl_basic_set_drop(context, type, pos, 1);
1229 if (!n_lower && !n_upper)
1230 return fn(NULL, NULL, context, user);
1231 if (!n_lower)
1232 return foreach_upper_bound(bset, type, abs_pos, context, n_upper,
1233 fn, user);
1234 if (!n_upper)
1235 return foreach_lower_bound(bset, type, abs_pos, context, n_lower,
1236 fn, user);
1237 return foreach_bound_pair(bset, type, abs_pos, context, n_lower, n_upper,
1238 fn, user);
1239 error:
1240 isl_constraint_free(lower);
1241 isl_constraint_free(upper);
1242 isl_basic_set_free(context);
1243 return isl_stat_error;
1244 }
1245
1246 __isl_give isl_aff *isl_constraint_get_bound(
1247 __isl_keep isl_constraint *constraint, enum isl_dim_type type, int pos)
1248 {
1249 isl_aff *aff;
1250 isl_ctx *ctx;
1251
1252 if (!constraint)
1253 return NULL;
1254 ctx = isl_constraint_get_ctx(constraint);
1255 if (pos >= isl_constraint_dim(constraint, type))
1256 isl_die(ctx, isl_error_invalid,
1257 "index out of bounds", return NULL);
1258 if (isl_constraint_dim(constraint, isl_dim_in) != 0)
1259 isl_die(ctx, isl_error_invalid,
1260 "not a set constraint", return NULL);
1261
1262 pos += offset(constraint, type);
1263 if (isl_int_is_zero(constraint->v->el[pos]))
1264 isl_die(ctx, isl_error_invalid,
1265 "constraint does not define a bound on given dimension",
1266 return NULL);
1267
1268 aff = isl_aff_alloc(isl_local_space_copy(constraint->ls));
1269 if (!aff)
1270 return NULL;
1271
1272 if (isl_int_is_neg(constraint->v->el[pos]))
1273 isl_seq_cpy(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1274 else
1275 isl_seq_neg(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1276 isl_int_set_si(aff->v->el[1 + pos], 0);
1277 isl_int_abs(aff->v->el[0], constraint->v->el[pos]);
1278
1279 return aff;
1280 }
1281
1282 /* For an inequality constraint
1283 *
1284 * f >= 0
1285 *
1286 * or an equality constraint
1287 *
1288 * f = 0
1289 *
1290 * return the affine expression f.
1291 */
1292 __isl_give isl_aff *isl_constraint_get_aff(
1293 __isl_keep isl_constraint *constraint)
1294 {
1295 isl_aff *aff;
1296
1297 if (!constraint)
1298 return NULL;
1299
1300 aff = isl_aff_alloc(isl_local_space_copy(constraint->ls));
1301 if (!aff)
1302 return NULL;
1303
1304 isl_seq_cpy(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1305 isl_int_set_si(aff->v->el[0], 1);
1306
1307 return aff;
1308 }
1309
1310 /* Construct an inequality (eq = 0) or equality (eq = 1) constraint from "aff".
1311 * In particular, construct aff >= 0 or aff = 0.
1312 *
1313 * The denominator of "aff" can be ignored.
1314 */
1315 static __isl_give isl_constraint *isl_constraint_alloc_aff(int eq,
1316 __isl_take isl_aff *aff)
1317 {
1318 isl_local_space *ls;
1319 isl_vec *v;
1320
1321 if (!aff)
1322 return NULL;
1323 ls = isl_aff_get_domain_local_space(aff);
1324 v = isl_vec_drop_els(isl_vec_copy(aff->v), 0, 1);
1325 isl_aff_free(aff);
1326
1327 return isl_constraint_alloc_vec(eq, ls, v);
1328 }
1329
1330 /* Construct an equality constraint equating the given affine expression
1331 * to zero.
1332 */
1333 __isl_give isl_constraint *isl_equality_from_aff(__isl_take isl_aff *aff)
1334 {
1335 return isl_constraint_alloc_aff(1, aff);
1336 }
1337
1338 /* Construct an inequality constraint enforcing the given affine expression
1339 * to be non-negative.
1340 */
1341 __isl_give isl_constraint *isl_inequality_from_aff(__isl_take isl_aff *aff)
1342 {
1343 return isl_constraint_alloc_aff(0, aff);
1344 }
1345
1346 /* Compare two isl_constraints.
1347 *
1348 * Return -1 if "c1" is "smaller" than "c2", 1 if "c1" is "greater"
1349 * than "c2" and 0 if they are equal.
1350 *
1351 * The order is fairly arbitrary. We do consider constraints that only involve
1352 * earlier dimensions as "smaller".
1353 */
1354 int isl_constraint_plain_cmp(__isl_keep isl_constraint *c1,
1355 __isl_keep isl_constraint *c2)
1356 {
1357 int cmp;
1358 int last1, last2;
1359
1360 if (c1 == c2)
1361 return 0;
1362 if (!c1)
1363 return -1;
1364 if (!c2)
1365 return 1;
1366 cmp = isl_local_space_cmp(c1->ls, c2->ls);
1367 if (cmp != 0)
1368 return cmp;
1369
1370 last1 = isl_seq_last_non_zero(c1->v->el + 1, c1->v->size - 1);
1371 last2 = isl_seq_last_non_zero(c2->v->el + 1, c1->v->size - 1);
1372 if (last1 != last2)
1373 return last1 - last2;
1374
1375 return isl_seq_cmp(c1->v->el, c2->v->el, c1->v->size);
1376 }
1377
1378 /* Compare two constraints based on their final (non-zero) coefficients.
1379 * In particular, the constraint that involves later variables or
1380 * that has a larger coefficient for a shared latest variable
1381 * is considered "greater" than the other constraint.
1382 *
1383 * Return -1 if "c1" is "smaller" than "c2", 1 if "c1" is "greater"
1384 * than "c2" and 0 if they are equal.
1385 *
1386 * If the constraints live in different local spaces, then we cannot
1387 * really compare the constraints so we compare the local spaces instead.
1388 */
1389 int isl_constraint_cmp_last_non_zero(__isl_keep isl_constraint *c1,
1390 __isl_keep isl_constraint *c2)
1391 {
1392 int cmp;
1393 int last1, last2;
1394
1395 if (c1 == c2)
1396 return 0;
1397 if (!c1)
1398 return -1;
1399 if (!c2)
1400 return 1;
1401 cmp = isl_local_space_cmp(c1->ls, c2->ls);
1402 if (cmp != 0)
1403 return cmp;
1404
1405 last1 = isl_seq_last_non_zero(c1->v->el + 1, c1->v->size - 1);
1406 last2 = isl_seq_last_non_zero(c2->v->el + 1, c1->v->size - 1);
1407 if (last1 != last2)
1408 return last1 - last2;
1409 if (last1 == -1)
1410 return 0;
1411 return isl_int_abs_cmp(c1->v->el[1 + last1], c2->v->el[1 + last2]);
1412 }
Integer set library