Merge branch 'maint'
[isl.git] / isl_constraint.c
blob613732355c42c8161c073e24d64a9e3bae1f03ad
1 /*
2 * Copyright 2008-2009 Katholieke Universiteit Leuven
3 * Copyright 2010 INRIA Saclay
5 * Use of this software is governed by the MIT license
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
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>
23 #undef BASE
24 #define BASE constraint
26 #include <isl_list_templ.c>
28 isl_ctx *isl_constraint_get_ctx(__isl_keep isl_constraint *c)
30 return c ? isl_local_space_get_ctx(c->ls) : NULL;
33 static unsigned n(struct isl_constraint *c, enum isl_dim_type type)
35 return isl_local_space_dim(c->ls, type);
38 static unsigned offset(struct isl_constraint *c, enum isl_dim_type type)
40 return isl_local_space_offset(c->ls, type);
43 static unsigned basic_map_offset(__isl_keep isl_basic_map *bmap,
44 enum isl_dim_type type)
46 return type == isl_dim_div ? 1 + isl_space_dim(bmap->dim, isl_dim_all)
47 : 1 + isl_space_offset(bmap->dim, type);
50 static unsigned basic_set_offset(struct isl_basic_set *bset,
51 enum isl_dim_type type)
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;
63 __isl_give isl_constraint *isl_constraint_alloc_vec(int eq,
64 __isl_take isl_local_space *ls, __isl_take isl_vec *v)
66 isl_constraint *constraint;
68 if (!ls || !v)
69 goto error;
71 constraint = isl_alloc_type(isl_vec_get_ctx(v), isl_constraint);
72 if (!constraint)
73 goto error;
75 constraint->ref = 1;
76 constraint->eq = eq;
77 constraint->ls = ls;
78 constraint->v = v;
80 return constraint;
81 error:
82 isl_local_space_free(ls);
83 isl_vec_free(v);
84 return NULL;
87 __isl_give isl_constraint *isl_constraint_alloc(int eq,
88 __isl_take isl_local_space *ls)
90 isl_ctx *ctx;
91 isl_vec *v;
93 if (!ls)
94 return NULL;
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);
102 struct isl_constraint *isl_basic_map_constraint(struct isl_basic_map *bmap,
103 isl_int **line)
105 int eq;
106 isl_ctx *ctx;
107 isl_vec *v;
108 isl_local_space *ls = NULL;
109 isl_constraint *constraint;
111 if (!bmap || !line)
112 goto error;
114 eq = line >= bmap->eq;
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);
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;
132 struct isl_constraint *isl_basic_set_constraint(struct isl_basic_set *bset,
133 isl_int **line)
135 return isl_basic_map_constraint((struct isl_basic_map *)bset, line);
138 __isl_give isl_constraint *isl_equality_alloc(__isl_take isl_local_space *ls)
140 return isl_constraint_alloc(1, ls);
143 __isl_give isl_constraint *isl_inequality_alloc(__isl_take isl_local_space *ls)
145 return isl_constraint_alloc(0, ls);
148 struct isl_constraint *isl_constraint_dup(struct isl_constraint *c)
150 if (!c)
151 return NULL;
153 return isl_constraint_alloc_vec(c->eq, isl_local_space_copy(c->ls),
154 isl_vec_copy(c->v));
157 struct isl_constraint *isl_constraint_cow(struct isl_constraint *c)
159 if (!c)
160 return NULL;
162 if (c->ref == 1)
163 return c;
164 c->ref--;
165 return isl_constraint_dup(c);
168 struct isl_constraint *isl_constraint_copy(struct isl_constraint *constraint)
170 if (!constraint)
171 return NULL;
173 constraint->ref++;
174 return constraint;
177 void *isl_constraint_free(struct isl_constraint *c)
179 if (!c)
180 return NULL;
182 if (--c->ref > 0)
183 return NULL;
185 isl_local_space_free(c->ls);
186 isl_vec_free(c->v);
187 free(c);
189 return NULL;
192 /* Return the number of constraints in "bset", i.e., the
193 * number of times isl_basic_set_foreach_constraint will
194 * call the callback.
196 int isl_basic_set_n_constraint(__isl_keep isl_basic_set *bset)
198 if (!bset)
199 return -1;
201 return bset->n_eq + bset->n_ineq;
204 int isl_basic_map_foreach_constraint(__isl_keep isl_basic_map *bmap,
205 int (*fn)(__isl_take isl_constraint *c, void *user), void *user)
207 int i;
208 struct isl_constraint *c;
210 if (!bmap)
211 return -1;
213 isl_assert(bmap->ctx, ISL_F_ISSET(bmap, ISL_BASIC_MAP_FINAL),
214 return -1);
216 for (i = 0; i < bmap->n_eq; ++i) {
217 c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
218 &bmap->eq[i]);
219 if (!c)
220 return -1;
221 if (fn(c, user) < 0)
222 return -1;
225 for (i = 0; i < bmap->n_ineq; ++i) {
226 c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
227 &bmap->ineq[i]);
228 if (!c)
229 return -1;
230 if (fn(c, user) < 0)
231 return -1;
234 return 0;
237 int isl_basic_set_foreach_constraint(__isl_keep isl_basic_set *bset,
238 int (*fn)(__isl_take isl_constraint *c, void *user), void *user)
240 return isl_basic_map_foreach_constraint((isl_basic_map *)bset, fn, user);
243 int isl_constraint_is_equal(struct isl_constraint *constraint1,
244 struct isl_constraint *constraint2)
246 int equal;
248 if (!constraint1 || !constraint2)
249 return 0;
250 if (constraint1->eq != constraint2->eq)
251 return 0;
252 equal = isl_local_space_is_equal(constraint1->ls, constraint2->ls);
253 if (equal < 0 || !equal)
254 return equal;
255 return isl_vec_is_equal(constraint1->v, constraint2->v);
258 struct isl_basic_map *isl_basic_map_add_constraint(
259 struct isl_basic_map *bmap, struct isl_constraint *constraint)
261 isl_ctx *ctx;
262 isl_space *dim;
263 int equal_space;
265 if (!bmap || !constraint)
266 goto error;
268 ctx = isl_constraint_get_ctx(constraint);
269 dim = isl_constraint_get_space(constraint);
270 equal_space = isl_space_is_equal(bmap->dim, dim);
271 isl_space_free(dim);
272 isl_assert(ctx, equal_space, goto error);
274 bmap = isl_basic_map_intersect(bmap,
275 isl_basic_map_from_constraint(constraint));
276 return bmap;
277 error:
278 isl_basic_map_free(bmap);
279 isl_constraint_free(constraint);
280 return NULL;
283 struct isl_basic_set *isl_basic_set_add_constraint(
284 struct isl_basic_set *bset, struct isl_constraint *constraint)
286 return (struct isl_basic_set *)
287 isl_basic_map_add_constraint((struct isl_basic_map *)bset,
288 constraint);
291 __isl_give isl_map *isl_map_add_constraint(__isl_take isl_map *map,
292 __isl_take isl_constraint *constraint)
294 isl_basic_map *bmap;
296 bmap = isl_basic_map_from_constraint(constraint);
297 map = isl_map_intersect(map, isl_map_from_basic_map(bmap));
299 return map;
302 __isl_give isl_set *isl_set_add_constraint(__isl_take isl_set *set,
303 __isl_take isl_constraint *constraint)
305 return isl_map_add_constraint(set, constraint);
308 __isl_give isl_space *isl_constraint_get_space(
309 __isl_keep isl_constraint *constraint)
311 return constraint ? isl_local_space_get_space(constraint->ls) : NULL;
314 __isl_give isl_local_space *isl_constraint_get_local_space(
315 __isl_keep isl_constraint *constraint)
317 return constraint ? isl_local_space_copy(constraint->ls) : NULL;
320 int isl_constraint_dim(struct isl_constraint *constraint,
321 enum isl_dim_type type)
323 if (!constraint)
324 return -1;
325 return n(constraint, type);
328 int isl_constraint_involves_dims(__isl_keep isl_constraint *constraint,
329 enum isl_dim_type type, unsigned first, unsigned n)
331 int i;
332 isl_ctx *ctx;
333 int *active = NULL;
334 int involves = 0;
336 if (!constraint)
337 return -1;
338 if (n == 0)
339 return 0;
341 ctx = isl_constraint_get_ctx(constraint);
342 if (first + n > isl_constraint_dim(constraint, type))
343 isl_die(ctx, isl_error_invalid,
344 "range out of bounds", return -1);
346 active = isl_local_space_get_active(constraint->ls,
347 constraint->v->el + 1);
348 if (!active)
349 goto error;
351 first += isl_local_space_offset(constraint->ls, type) - 1;
352 for (i = 0; i < n; ++i)
353 if (active[first + i]) {
354 involves = 1;
355 break;
358 free(active);
360 return involves;
361 error:
362 free(active);
363 return -1;
366 /* Does the given constraint represent a lower bound on the given
367 * dimension?
369 int isl_constraint_is_lower_bound(__isl_keep isl_constraint *constraint,
370 enum isl_dim_type type, unsigned pos)
372 if (!constraint)
373 return -1;
375 if (pos >= isl_local_space_dim(constraint->ls, type))
376 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
377 "position out of bounds", return -1);
379 pos += isl_local_space_offset(constraint->ls, type);
380 return isl_int_is_pos(constraint->v->el[pos]);
383 /* Does the given constraint represent an upper bound on the given
384 * dimension?
386 int isl_constraint_is_upper_bound(__isl_keep isl_constraint *constraint,
387 enum isl_dim_type type, unsigned pos)
389 if (!constraint)
390 return -1;
392 if (pos >= isl_local_space_dim(constraint->ls, type))
393 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
394 "position out of bounds", return -1);
396 pos += isl_local_space_offset(constraint->ls, type);
397 return isl_int_is_neg(constraint->v->el[pos]);
400 const char *isl_constraint_get_dim_name(__isl_keep isl_constraint *constraint,
401 enum isl_dim_type type, unsigned pos)
403 return constraint ?
404 isl_local_space_get_dim_name(constraint->ls, type, pos) : NULL;
407 void isl_constraint_get_constant(struct isl_constraint *constraint, isl_int *v)
409 if (!constraint)
410 return;
411 isl_int_set(*v, constraint->v->el[0]);
414 /* Return the constant term of "constraint".
416 __isl_give isl_val *isl_constraint_get_constant_val(
417 __isl_keep isl_constraint *constraint)
419 isl_ctx *ctx;
421 if (!constraint)
422 return NULL;
424 ctx = isl_constraint_get_ctx(constraint);
425 return isl_val_int_from_isl_int(ctx, constraint->v->el[0]);
428 void isl_constraint_get_coefficient(struct isl_constraint *constraint,
429 enum isl_dim_type type, int pos, isl_int *v)
431 if (!constraint)
432 return;
434 if (pos >= isl_local_space_dim(constraint->ls, type))
435 isl_die(constraint->v->ctx, isl_error_invalid,
436 "position out of bounds", return);
438 pos += isl_local_space_offset(constraint->ls, type);
439 isl_int_set(*v, constraint->v->el[pos]);
442 /* Return the coefficient of the variable of type "type" at position "pos"
443 * of "constraint".
445 __isl_give isl_val *isl_constraint_get_coefficient_val(
446 __isl_keep isl_constraint *constraint, enum isl_dim_type type, int pos)
448 isl_ctx *ctx;
450 if (!constraint)
451 return NULL;
453 ctx = isl_constraint_get_ctx(constraint);
454 if (pos < 0 || pos >= isl_local_space_dim(constraint->ls, type))
455 isl_die(ctx, isl_error_invalid,
456 "position out of bounds", return NULL);
458 pos += isl_local_space_offset(constraint->ls, type);
459 return isl_val_int_from_isl_int(ctx, constraint->v->el[pos]);
462 __isl_give isl_aff *isl_constraint_get_div(__isl_keep isl_constraint *constraint,
463 int pos)
465 if (!constraint)
466 return NULL;
468 return isl_local_space_get_div(constraint->ls, pos);
471 __isl_give isl_constraint *isl_constraint_set_constant(
472 __isl_take isl_constraint *constraint, isl_int v)
474 constraint = isl_constraint_cow(constraint);
475 if (!constraint)
476 return NULL;
478 constraint->v = isl_vec_cow(constraint->v);
479 if (!constraint->v)
480 return isl_constraint_free(constraint);
482 isl_int_set(constraint->v->el[0], v);
483 return constraint;
486 /* Replace the constant term of "constraint" by "v".
488 __isl_give isl_constraint *isl_constraint_set_constant_val(
489 __isl_take isl_constraint *constraint, __isl_take isl_val *v)
491 constraint = isl_constraint_cow(constraint);
492 if (!constraint || !v)
493 goto error;
494 if (!isl_val_is_int(v))
495 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
496 "expecting integer value", goto error);
497 constraint->v = isl_vec_set_element_val(constraint->v, 0, v);
498 if (!constraint->v)
499 constraint = isl_constraint_free(constraint);
500 return constraint;
501 error:
502 isl_val_free(v);
503 return isl_constraint_free(constraint);
506 __isl_give isl_constraint *isl_constraint_set_constant_si(
507 __isl_take isl_constraint *constraint, int v)
509 constraint = isl_constraint_cow(constraint);
510 if (!constraint)
511 return NULL;
513 constraint->v = isl_vec_cow(constraint->v);
514 if (!constraint->v)
515 return isl_constraint_free(constraint);
517 isl_int_set_si(constraint->v->el[0], v);
518 return constraint;
521 __isl_give isl_constraint *isl_constraint_set_coefficient(
522 __isl_take isl_constraint *constraint,
523 enum isl_dim_type type, int pos, isl_int v)
525 constraint = isl_constraint_cow(constraint);
526 if (!constraint)
527 return NULL;
529 if (pos >= isl_local_space_dim(constraint->ls, type))
530 isl_die(constraint->v->ctx, isl_error_invalid,
531 "position out of bounds",
532 return isl_constraint_free(constraint));
534 constraint = isl_constraint_cow(constraint);
535 if (!constraint)
536 return NULL;
538 constraint->v = isl_vec_cow(constraint->v);
539 if (!constraint->v)
540 return isl_constraint_free(constraint);
542 pos += isl_local_space_offset(constraint->ls, type);
543 isl_int_set(constraint->v->el[pos], v);
545 return constraint;
548 /* Replace the coefficient of the variable of type "type" at position "pos"
549 * of "constraint" by "v".
551 __isl_give isl_constraint *isl_constraint_set_coefficient_val(
552 __isl_take isl_constraint *constraint,
553 enum isl_dim_type type, int pos, isl_val *v)
555 constraint = isl_constraint_cow(constraint);
556 if (!constraint || !v)
557 goto error;
558 if (!isl_val_is_int(v))
559 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
560 "expecting integer value", goto error);
562 if (pos >= isl_local_space_dim(constraint->ls, type))
563 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
564 "position out of bounds", goto error);
566 pos += isl_local_space_offset(constraint->ls, type);
567 constraint->v = isl_vec_set_element_val(constraint->v, pos, v);
568 if (!constraint->v)
569 constraint = isl_constraint_free(constraint);
570 return constraint;
571 error:
572 isl_val_free(v);
573 return isl_constraint_free(constraint);
576 __isl_give isl_constraint *isl_constraint_set_coefficient_si(
577 __isl_take isl_constraint *constraint,
578 enum isl_dim_type type, int pos, int v)
580 constraint = isl_constraint_cow(constraint);
581 if (!constraint)
582 return NULL;
584 if (pos >= isl_local_space_dim(constraint->ls, type))
585 isl_die(constraint->v->ctx, isl_error_invalid,
586 "position out of bounds",
587 return isl_constraint_free(constraint));
589 constraint = isl_constraint_cow(constraint);
590 if (!constraint)
591 return NULL;
593 constraint->v = isl_vec_cow(constraint->v);
594 if (!constraint->v)
595 return isl_constraint_free(constraint);
597 pos += isl_local_space_offset(constraint->ls, type);
598 isl_int_set_si(constraint->v->el[pos], v);
600 return constraint;
603 /* Drop any constraint from "bset" that is identical to "constraint".
604 * In particular, this means that the local spaces of "bset" and
605 * "constraint" need to be the same.
607 * Since the given constraint may actually be a pointer into the bset,
608 * we have to be careful not to reorder the constraints as the user
609 * may be holding on to other constraints from the same bset.
610 * This should be cleaned up when the internal representation of
611 * isl_constraint is changed to use isl_aff.
613 __isl_give isl_basic_set *isl_basic_set_drop_constraint(
614 __isl_take isl_basic_set *bset, __isl_take isl_constraint *constraint)
616 int i;
617 unsigned n;
618 isl_int **row;
619 unsigned total;
620 isl_local_space *ls1;
621 int equal;
623 if (!bset || !constraint)
624 goto error;
626 ls1 = isl_basic_set_get_local_space(bset);
627 equal = isl_local_space_is_equal(ls1, constraint->ls);
628 isl_local_space_free(ls1);
629 if (equal < 0)
630 goto error;
631 if (!equal) {
632 isl_constraint_free(constraint);
633 return bset;
636 if (isl_constraint_is_equality(constraint)) {
637 n = bset->n_eq;
638 row = bset->eq;
639 } else {
640 n = bset->n_ineq;
641 row = bset->ineq;
644 total = isl_constraint_dim(constraint, isl_dim_all);
645 for (i = 0; i < n; ++i)
646 if (isl_seq_eq(row[i], constraint->v->el, 1 + total))
647 isl_seq_clr(row[i], 1 + total);
649 isl_constraint_free(constraint);
650 return bset;
651 error:
652 isl_constraint_free(constraint);
653 isl_basic_set_free(bset);
654 return NULL;
657 struct isl_constraint *isl_constraint_negate(struct isl_constraint *constraint)
659 isl_ctx *ctx;
661 constraint = isl_constraint_cow(constraint);
662 if (!constraint)
663 return NULL;
665 ctx = isl_constraint_get_ctx(constraint);
666 if (isl_constraint_is_equality(constraint))
667 isl_die(ctx, isl_error_invalid, "cannot negate equality",
668 return isl_constraint_free(constraint));
669 constraint->v = isl_vec_neg(constraint->v);
670 constraint->v = isl_vec_cow(constraint->v);
671 if (!constraint->v)
672 return isl_constraint_free(constraint);
673 isl_int_sub_ui(constraint->v->el[0], constraint->v->el[0], 1);
674 return constraint;
677 int isl_constraint_is_equality(struct isl_constraint *constraint)
679 if (!constraint)
680 return -1;
681 return constraint->eq;
684 int isl_constraint_is_div_constraint(__isl_keep isl_constraint *constraint)
686 int i;
687 int n_div;
689 if (!constraint)
690 return -1;
691 if (isl_constraint_is_equality(constraint))
692 return 0;
693 n_div = isl_constraint_dim(constraint, isl_dim_div);
694 for (i = 0; i < n_div; ++i) {
695 if (isl_local_space_is_div_constraint(constraint->ls,
696 constraint->v->el, i))
697 return 1;
700 return 0;
703 /* We manually set ISL_BASIC_SET_FINAL instead of calling
704 * isl_basic_map_finalize because we want to keep the position
705 * of the divs and we therefore do not want to throw away redundant divs.
706 * This is arguably a bit fragile.
708 __isl_give isl_basic_map *isl_basic_map_from_constraint(
709 __isl_take isl_constraint *constraint)
711 int k;
712 isl_local_space *ls;
713 struct isl_basic_map *bmap;
714 isl_int *c;
715 unsigned total;
717 if (!constraint)
718 return NULL;
720 ls = isl_local_space_copy(constraint->ls);
721 bmap = isl_basic_map_from_local_space(ls);
722 bmap = isl_basic_map_extend_constraints(bmap, 1, 1);
723 if (isl_constraint_is_equality(constraint)) {
724 k = isl_basic_map_alloc_equality(bmap);
725 if (k < 0)
726 goto error;
727 c = bmap->eq[k];
729 else {
730 k = isl_basic_map_alloc_inequality(bmap);
731 if (k < 0)
732 goto error;
733 c = bmap->ineq[k];
735 total = isl_basic_map_total_dim(bmap);
736 isl_seq_cpy(c, constraint->v->el, 1 + total);
737 isl_constraint_free(constraint);
738 if (bmap)
739 ISL_F_SET(bmap, ISL_BASIC_SET_FINAL);
740 return bmap;
741 error:
742 isl_constraint_free(constraint);
743 isl_basic_map_free(bmap);
744 return NULL;
747 struct isl_basic_set *isl_basic_set_from_constraint(
748 struct isl_constraint *constraint)
750 if (!constraint)
751 return NULL;
753 if (isl_constraint_dim(constraint, isl_dim_in) != 0)
754 isl_die(isl_constraint_get_ctx(constraint), isl_error_invalid,
755 "not a set constraint",
756 return isl_constraint_free(constraint));
757 return (isl_basic_set *)isl_basic_map_from_constraint(constraint);
760 int isl_basic_map_has_defining_equality(
761 __isl_keep isl_basic_map *bmap, enum isl_dim_type type, int pos,
762 __isl_give isl_constraint **c)
764 int i;
765 unsigned offset;
766 unsigned total;
768 if (!bmap)
769 return -1;
770 offset = basic_map_offset(bmap, type);
771 total = isl_basic_map_total_dim(bmap);
772 isl_assert(bmap->ctx, pos < isl_basic_map_dim(bmap, type), return -1);
773 for (i = 0; i < bmap->n_eq; ++i)
774 if (!isl_int_is_zero(bmap->eq[i][offset + pos]) &&
775 isl_seq_first_non_zero(bmap->eq[i]+offset+pos+1,
776 1+total-offset-pos-1) == -1) {
777 *c = isl_basic_map_constraint(isl_basic_map_copy(bmap),
778 &bmap->eq[i]);
779 return 1;
781 return 0;
784 int isl_basic_set_has_defining_equality(
785 __isl_keep isl_basic_set *bset, enum isl_dim_type type, int pos,
786 __isl_give isl_constraint **c)
788 return isl_basic_map_has_defining_equality((isl_basic_map *)bset,
789 type, pos, c);
792 int isl_basic_set_has_defining_inequalities(
793 struct isl_basic_set *bset, enum isl_dim_type type, int pos,
794 struct isl_constraint **lower,
795 struct isl_constraint **upper)
797 int i, j;
798 unsigned offset;
799 unsigned total;
800 isl_int m;
801 isl_int **lower_line, **upper_line;
803 if (!bset)
804 return -1;
805 offset = basic_set_offset(bset, type);
806 total = isl_basic_set_total_dim(bset);
807 isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type), return -1);
808 isl_int_init(m);
809 for (i = 0; i < bset->n_ineq; ++i) {
810 if (isl_int_is_zero(bset->ineq[i][offset + pos]))
811 continue;
812 if (isl_int_is_one(bset->ineq[i][offset + pos]))
813 continue;
814 if (isl_int_is_negone(bset->ineq[i][offset + pos]))
815 continue;
816 if (isl_seq_first_non_zero(bset->ineq[i]+offset+pos+1,
817 1+total-offset-pos-1) != -1)
818 continue;
819 for (j = i + 1; j < bset->n_ineq; ++j) {
820 if (!isl_seq_is_neg(bset->ineq[i]+1, bset->ineq[j]+1,
821 total))
822 continue;
823 isl_int_add(m, bset->ineq[i][0], bset->ineq[j][0]);
824 if (isl_int_abs_ge(m, bset->ineq[i][offset+pos]))
825 continue;
827 if (isl_int_is_pos(bset->ineq[i][offset+pos])) {
828 lower_line = &bset->ineq[i];
829 upper_line = &bset->ineq[j];
830 } else {
831 lower_line = &bset->ineq[j];
832 upper_line = &bset->ineq[i];
834 *lower = isl_basic_set_constraint(
835 isl_basic_set_copy(bset), lower_line);
836 *upper = isl_basic_set_constraint(
837 isl_basic_set_copy(bset), upper_line);
838 isl_int_clear(m);
839 return 1;
842 *lower = NULL;
843 *upper = NULL;
844 isl_int_clear(m);
845 return 0;
848 /* Given two constraints "a" and "b" on the variable at position "abs_pos"
849 * (in "a" and "b"), add a constraint to "bset" that ensures that the
850 * bound implied by "a" is (strictly) larger than the bound implied by "b".
852 * If both constraints imply lower bounds, then this means that "a" is
853 * active in the result.
854 * If both constraints imply upper bounds, then this means that "b" is
855 * active in the result.
857 static __isl_give isl_basic_set *add_larger_bound_constraint(
858 __isl_take isl_basic_set *bset, isl_int *a, isl_int *b,
859 unsigned abs_pos, int strict)
861 int k;
862 isl_int t;
863 unsigned total;
865 k = isl_basic_set_alloc_inequality(bset);
866 if (k < 0)
867 goto error;
869 total = isl_basic_set_dim(bset, isl_dim_all);
871 isl_int_init(t);
872 isl_int_neg(t, b[1 + abs_pos]);
874 isl_seq_combine(bset->ineq[k], t, a, a[1 + abs_pos], b, 1 + abs_pos);
875 isl_seq_combine(bset->ineq[k] + 1 + abs_pos,
876 t, a + 1 + abs_pos + 1, a[1 + abs_pos], b + 1 + abs_pos + 1,
877 total - abs_pos);
879 if (strict)
880 isl_int_sub_ui(bset->ineq[k][0], bset->ineq[k][0], 1);
882 isl_int_clear(t);
884 return bset;
885 error:
886 isl_basic_set_free(bset);
887 return NULL;
890 /* Add constraints to "context" that ensure that "u" is the smallest
891 * (and therefore active) upper bound on "abs_pos" in "bset" and return
892 * the resulting basic set.
894 static __isl_give isl_basic_set *set_smallest_upper_bound(
895 __isl_keep isl_basic_set *context,
896 __isl_keep isl_basic_set *bset, unsigned abs_pos, int n_upper, int u)
898 int j;
900 context = isl_basic_set_copy(context);
901 context = isl_basic_set_cow(context);
903 context = isl_basic_set_extend_constraints(context, 0, n_upper - 1);
905 for (j = 0; j < bset->n_ineq; ++j) {
906 if (j == u)
907 continue;
908 if (!isl_int_is_neg(bset->ineq[j][1 + abs_pos]))
909 continue;
910 context = add_larger_bound_constraint(context,
911 bset->ineq[j], bset->ineq[u], abs_pos, j > u);
914 context = isl_basic_set_simplify(context);
915 context = isl_basic_set_finalize(context);
917 return context;
920 /* Add constraints to "context" that ensure that "u" is the largest
921 * (and therefore active) upper bound on "abs_pos" in "bset" and return
922 * the resulting basic set.
924 static __isl_give isl_basic_set *set_largest_lower_bound(
925 __isl_keep isl_basic_set *context,
926 __isl_keep isl_basic_set *bset, unsigned abs_pos, int n_lower, int l)
928 int j;
930 context = isl_basic_set_copy(context);
931 context = isl_basic_set_cow(context);
933 context = isl_basic_set_extend_constraints(context, 0, n_lower - 1);
935 for (j = 0; j < bset->n_ineq; ++j) {
936 if (j == l)
937 continue;
938 if (!isl_int_is_pos(bset->ineq[j][1 + abs_pos]))
939 continue;
940 context = add_larger_bound_constraint(context,
941 bset->ineq[l], bset->ineq[j], abs_pos, j > l);
944 context = isl_basic_set_simplify(context);
945 context = isl_basic_set_finalize(context);
947 return context;
950 static int foreach_upper_bound(__isl_keep isl_basic_set *bset,
951 enum isl_dim_type type, unsigned abs_pos,
952 __isl_take isl_basic_set *context, int n_upper,
953 int (*fn)(__isl_take isl_constraint *lower,
954 __isl_take isl_constraint *upper,
955 __isl_take isl_basic_set *bset, void *user), void *user)
957 isl_basic_set *context_i;
958 isl_constraint *upper = NULL;
959 int i;
961 for (i = 0; i < bset->n_ineq; ++i) {
962 if (isl_int_is_zero(bset->ineq[i][1 + abs_pos]))
963 continue;
965 context_i = set_smallest_upper_bound(context, bset,
966 abs_pos, n_upper, i);
967 if (isl_basic_set_is_empty(context_i)) {
968 isl_basic_set_free(context_i);
969 continue;
971 upper = isl_basic_set_constraint(isl_basic_set_copy(bset),
972 &bset->ineq[i]);
973 if (!upper || !context_i)
974 goto error;
975 if (fn(NULL, upper, context_i, user) < 0)
976 break;
979 isl_basic_set_free(context);
981 if (i < bset->n_ineq)
982 return -1;
984 return 0;
985 error:
986 isl_constraint_free(upper);
987 isl_basic_set_free(context_i);
988 isl_basic_set_free(context);
989 return -1;
992 static int foreach_lower_bound(__isl_keep isl_basic_set *bset,
993 enum isl_dim_type type, unsigned abs_pos,
994 __isl_take isl_basic_set *context, int n_lower,
995 int (*fn)(__isl_take isl_constraint *lower,
996 __isl_take isl_constraint *upper,
997 __isl_take isl_basic_set *bset, void *user), void *user)
999 isl_basic_set *context_i;
1000 isl_constraint *lower = NULL;
1001 int i;
1003 for (i = 0; i < bset->n_ineq; ++i) {
1004 if (isl_int_is_zero(bset->ineq[i][1 + abs_pos]))
1005 continue;
1007 context_i = set_largest_lower_bound(context, bset,
1008 abs_pos, n_lower, i);
1009 if (isl_basic_set_is_empty(context_i)) {
1010 isl_basic_set_free(context_i);
1011 continue;
1013 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1014 &bset->ineq[i]);
1015 if (!lower || !context_i)
1016 goto error;
1017 if (fn(lower, NULL, context_i, user) < 0)
1018 break;
1021 isl_basic_set_free(context);
1023 if (i < bset->n_ineq)
1024 return -1;
1026 return 0;
1027 error:
1028 isl_constraint_free(lower);
1029 isl_basic_set_free(context_i);
1030 isl_basic_set_free(context);
1031 return -1;
1034 static int foreach_bound_pair(__isl_keep isl_basic_set *bset,
1035 enum isl_dim_type type, unsigned abs_pos,
1036 __isl_take isl_basic_set *context, int n_lower, int n_upper,
1037 int (*fn)(__isl_take isl_constraint *lower,
1038 __isl_take isl_constraint *upper,
1039 __isl_take isl_basic_set *bset, void *user), void *user)
1041 isl_basic_set *context_i, *context_j;
1042 isl_constraint *lower = NULL;
1043 isl_constraint *upper = NULL;
1044 int i, j;
1046 for (i = 0; i < bset->n_ineq; ++i) {
1047 if (!isl_int_is_pos(bset->ineq[i][1 + abs_pos]))
1048 continue;
1050 context_i = set_largest_lower_bound(context, bset,
1051 abs_pos, n_lower, i);
1052 if (isl_basic_set_is_empty(context_i)) {
1053 isl_basic_set_free(context_i);
1054 continue;
1057 for (j = 0; j < bset->n_ineq; ++j) {
1058 if (!isl_int_is_neg(bset->ineq[j][1 + abs_pos]))
1059 continue;
1061 context_j = set_smallest_upper_bound(context_i, bset,
1062 abs_pos, n_upper, j);
1063 context_j = isl_basic_set_extend_constraints(context_j,
1064 0, 1);
1065 context_j = add_larger_bound_constraint(context_j,
1066 bset->ineq[i], bset->ineq[j], abs_pos, 0);
1067 context_j = isl_basic_set_simplify(context_j);
1068 context_j = isl_basic_set_finalize(context_j);
1069 if (isl_basic_set_is_empty(context_j)) {
1070 isl_basic_set_free(context_j);
1071 continue;
1073 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1074 &bset->ineq[i]);
1075 upper = isl_basic_set_constraint(isl_basic_set_copy(bset),
1076 &bset->ineq[j]);
1077 if (!lower || !upper || !context_j)
1078 goto error;
1079 if (fn(lower, upper, context_j, user) < 0)
1080 break;
1083 isl_basic_set_free(context_i);
1085 if (j < bset->n_ineq)
1086 break;
1089 isl_basic_set_free(context);
1091 if (i < bset->n_ineq)
1092 return -1;
1094 return 0;
1095 error:
1096 isl_constraint_free(lower);
1097 isl_constraint_free(upper);
1098 isl_basic_set_free(context_i);
1099 isl_basic_set_free(context_j);
1100 isl_basic_set_free(context);
1101 return -1;
1104 /* For each pair of lower and upper bounds on the variable "pos"
1105 * of type "type", call "fn" with these lower and upper bounds and the
1106 * set of constraints on the remaining variables where these bounds
1107 * are active, i.e., (stricly) larger/smaller than the other lower/upper bounds.
1109 * If the designated variable is equal to an affine combination of the
1110 * other variables then fn is called with both lower and upper
1111 * set to the corresponding equality.
1113 * If there is no lower (or upper) bound, then NULL is passed
1114 * as the corresponding bound.
1116 * We first check if the variable is involved in any equality.
1117 * If not, we count the number of lower and upper bounds and
1118 * act accordingly.
1120 int isl_basic_set_foreach_bound_pair(__isl_keep isl_basic_set *bset,
1121 enum isl_dim_type type, unsigned pos,
1122 int (*fn)(__isl_take isl_constraint *lower,
1123 __isl_take isl_constraint *upper,
1124 __isl_take isl_basic_set *bset, void *user), void *user)
1126 int i;
1127 isl_constraint *lower = NULL;
1128 isl_constraint *upper = NULL;
1129 isl_basic_set *context = NULL;
1130 unsigned abs_pos;
1131 int n_lower, n_upper;
1133 if (!bset)
1134 return -1;
1135 isl_assert(bset->ctx, pos < isl_basic_set_dim(bset, type), return -1);
1136 isl_assert(bset->ctx, type == isl_dim_param || type == isl_dim_set,
1137 return -1);
1139 abs_pos = pos;
1140 if (type == isl_dim_set)
1141 abs_pos += isl_basic_set_dim(bset, isl_dim_param);
1143 for (i = 0; i < bset->n_eq; ++i) {
1144 if (isl_int_is_zero(bset->eq[i][1 + abs_pos]))
1145 continue;
1147 lower = isl_basic_set_constraint(isl_basic_set_copy(bset),
1148 &bset->eq[i]);
1149 upper = isl_constraint_copy(lower);
1150 context = isl_basic_set_remove_dims(isl_basic_set_copy(bset),
1151 type, pos, 1);
1152 if (!lower || !upper || !context)
1153 goto error;
1154 return fn(lower, upper, context, user);
1157 n_lower = 0;
1158 n_upper = 0;
1159 for (i = 0; i < bset->n_ineq; ++i) {
1160 if (isl_int_is_pos(bset->ineq[i][1 + abs_pos]))
1161 n_lower++;
1162 else if (isl_int_is_neg(bset->ineq[i][1 + abs_pos]))
1163 n_upper++;
1166 context = isl_basic_set_copy(bset);
1167 context = isl_basic_set_cow(context);
1168 if (!context)
1169 goto error;
1170 for (i = context->n_ineq - 1; i >= 0; --i)
1171 if (!isl_int_is_zero(context->ineq[i][1 + abs_pos]))
1172 isl_basic_set_drop_inequality(context, i);
1174 context = isl_basic_set_drop(context, type, pos, 1);
1175 if (!n_lower && !n_upper)
1176 return fn(NULL, NULL, context, user);
1177 if (!n_lower)
1178 return foreach_upper_bound(bset, type, abs_pos, context, n_upper,
1179 fn, user);
1180 if (!n_upper)
1181 return foreach_lower_bound(bset, type, abs_pos, context, n_lower,
1182 fn, user);
1183 return foreach_bound_pair(bset, type, abs_pos, context, n_lower, n_upper,
1184 fn, user);
1185 error:
1186 isl_constraint_free(lower);
1187 isl_constraint_free(upper);
1188 isl_basic_set_free(context);
1189 return -1;
1192 __isl_give isl_aff *isl_constraint_get_bound(
1193 __isl_keep isl_constraint *constraint, enum isl_dim_type type, int pos)
1195 isl_aff *aff;
1196 isl_ctx *ctx;
1198 if (!constraint)
1199 return NULL;
1200 ctx = isl_constraint_get_ctx(constraint);
1201 if (pos >= isl_constraint_dim(constraint, type))
1202 isl_die(ctx, isl_error_invalid,
1203 "index out of bounds", return NULL);
1204 if (isl_constraint_dim(constraint, isl_dim_in) != 0)
1205 isl_die(ctx, isl_error_invalid,
1206 "not a set constraint", return NULL);
1208 pos += offset(constraint, type);
1209 if (isl_int_is_zero(constraint->v->el[pos]))
1210 isl_die(ctx, isl_error_invalid,
1211 "constraint does not define a bound on given dimension",
1212 return NULL);
1214 aff = isl_aff_alloc(isl_local_space_copy(constraint->ls));
1215 if (!aff)
1216 return NULL;
1218 if (isl_int_is_neg(constraint->v->el[pos]))
1219 isl_seq_cpy(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1220 else
1221 isl_seq_neg(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1222 isl_int_set_si(aff->v->el[1 + pos], 0);
1223 isl_int_abs(aff->v->el[0], constraint->v->el[pos]);
1225 return aff;
1228 /* For an inequality constraint
1230 * f >= 0
1232 * or an equality constraint
1234 * f = 0
1236 * return the affine expression f.
1238 __isl_give isl_aff *isl_constraint_get_aff(
1239 __isl_keep isl_constraint *constraint)
1241 isl_aff *aff;
1243 if (!constraint)
1244 return NULL;
1246 aff = isl_aff_alloc(isl_local_space_copy(constraint->ls));
1247 if (!aff)
1248 return NULL;
1250 isl_seq_cpy(aff->v->el + 1, constraint->v->el, aff->v->size - 1);
1251 isl_int_set_si(aff->v->el[0], 1);
1253 return aff;
1256 /* Construct an inequality (eq = 0) or equality (eq = 1) constraint from "aff".
1257 * In particular, construct aff >= 0 or aff = 0.
1259 * The denominator of "aff" can be ignored.
1261 static __isl_give isl_constraint *isl_constraint_alloc_aff(int eq,
1262 __isl_take isl_aff *aff)
1264 isl_local_space *ls;
1265 isl_vec *v;
1267 if (!aff)
1268 return NULL;
1269 ls = isl_aff_get_domain_local_space(aff);
1270 v = isl_vec_drop_els(isl_vec_copy(aff->v), 0, 1);
1271 isl_aff_free(aff);
1273 return isl_constraint_alloc_vec(eq, ls, v);
1276 /* Construct an equality constraint equating the given affine expression
1277 * to zero.
1279 __isl_give isl_constraint *isl_equality_from_aff(__isl_take isl_aff *aff)
1281 return isl_constraint_alloc_aff(1, aff);
1284 /* Construct an inequality constraint enforcing the given affine expression
1285 * to be non-negative.
1287 __isl_give isl_constraint *isl_inequality_from_aff(__isl_take isl_aff *aff)
1289 return isl_constraint_alloc_aff(0, aff);