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add isl_qpolynomial_from_constraint
[isl.git] / isl_map_subtract.c
blob2cbdb0192901ffc2f07d379cd63628f213bcb820
1 /*
2 * Copyright 2008-2009 Katholieke Universiteit Leuven
3 *
4 * Use of this software is governed by the GNU LGPLv2.1 license
5 *
6 * Written by Sven Verdoolaege, K.U.Leuven, Departement
7 * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
8 */
9
10 #include "isl_seq.h"
11 #include "isl_set.h"
12 #include "isl_map.h"
13 #include "isl_map_private.h"
14 #include "isl_tab.h"
15 #include <isl_point_private.h>
16
17 static void expand_constraint(isl_vec *v, unsigned dim,
18 isl_int *c, int *div_map, unsigned n_div)
19 {
20 int i;
21
22 isl_seq_cpy(v->el, c, 1 + dim);
23 isl_seq_clr(v->el + 1 + dim, v->size - (1 + dim));
24
25 for (i = 0; i < n_div; ++i)
26 isl_int_set(v->el[1 + dim + div_map[i]], c[1 + dim + i]);
27 }
28
29 /* Add all constraints of bmap to tab. The equalities of bmap
30 * are added as a pair of inequalities.
31 */
32 static int tab_add_constraints(struct isl_tab *tab,
33 __isl_keep isl_basic_map *bmap, int *div_map)
34 {
35 int i;
36 unsigned dim;
37 unsigned tab_total;
38 unsigned bmap_total;
39 isl_vec *v;
40
41 if (!tab || !bmap)
42 return -1;
43
44 tab_total = isl_basic_map_total_dim(tab->bmap);
45 bmap_total = isl_basic_map_total_dim(bmap);
46 dim = isl_dim_total(tab->bmap->dim);
47
48 if (isl_tab_extend_cons(tab, 2 * bmap->n_eq + bmap->n_ineq) < 0)
49 return -1;
50
51 v = isl_vec_alloc(bmap->ctx, 1 + tab_total);
52
53 for (i = 0; i < bmap->n_eq; ++i) {
54 expand_constraint(v, dim, bmap->eq[i], div_map, bmap->n_div);
55 if (isl_tab_add_ineq(tab, v->el) < 0)
56 goto error;
57 isl_seq_neg(bmap->eq[i], bmap->eq[i], 1 + bmap_total);
58 expand_constraint(v, dim, bmap->eq[i], div_map, bmap->n_div);
59 if (isl_tab_add_ineq(tab, v->el) < 0)
60 goto error;
61 isl_seq_neg(bmap->eq[i], bmap->eq[i], 1 + bmap_total);
62 if (tab->empty)
63 break;
64 }
65
66 for (i = 0; i < bmap->n_ineq; ++i) {
67 expand_constraint(v, dim, bmap->ineq[i], div_map, bmap->n_div);
68 if (isl_tab_add_ineq(tab, v->el) < 0)
69 goto error;
70 if (tab->empty)
71 break;
72 }
73
74 isl_vec_free(v);
75 return 0;
76 error:
77 isl_vec_free(v);
78 return -1;
79 }
80
81 /* Add a specific constraint of bmap (or its opposite) to tab.
82 * The position of the constraint is specified by "c", where
83 * the equalities of bmap are counted twice, once for the inequality
84 * that is equal to the equality, and once for its negation.
85 */
86 static int tab_add_constraint(struct isl_tab *tab,
87 __isl_keep isl_basic_map *bmap, int *div_map, int c, int oppose)
88 {
89 unsigned dim;
90 unsigned tab_total;
91 unsigned bmap_total;
92 isl_vec *v;
93 int r;
94
95 if (!tab || !bmap)
96 return -1;
97
98 tab_total = isl_basic_map_total_dim(tab->bmap);
99 bmap_total = isl_basic_map_total_dim(bmap);
100 dim = isl_dim_total(tab->bmap->dim);
101
102 v = isl_vec_alloc(bmap->ctx, 1 + tab_total);
103 if (!v)
104 return -1;
105
106 if (c < 2 * bmap->n_eq) {
107 if ((c % 2) != oppose)
108 isl_seq_neg(bmap->eq[c/2], bmap->eq[c/2],
109 1 + bmap_total);
110 if (oppose)
111 isl_int_sub_ui(bmap->eq[c/2][0], bmap->eq[c/2][0], 1);
112 expand_constraint(v, dim, bmap->eq[c/2], div_map, bmap->n_div);
113 r = isl_tab_add_ineq(tab, v->el);
114 if (oppose)
115 isl_int_add_ui(bmap->eq[c/2][0], bmap->eq[c/2][0], 1);
116 if ((c % 2) != oppose)
117 isl_seq_neg(bmap->eq[c/2], bmap->eq[c/2],
118 1 + bmap_total);
119 } else {
120 c -= 2 * bmap->n_eq;
121 if (oppose) {
122 isl_seq_neg(bmap->ineq[c], bmap->ineq[c],
123 1 + bmap_total);
124 isl_int_sub_ui(bmap->ineq[c][0], bmap->ineq[c][0], 1);
125 }
126 expand_constraint(v, dim, bmap->ineq[c], div_map, bmap->n_div);
127 r = isl_tab_add_ineq(tab, v->el);
128 if (oppose) {
129 isl_int_add_ui(bmap->ineq[c][0], bmap->ineq[c][0], 1);
130 isl_seq_neg(bmap->ineq[c], bmap->ineq[c],
131 1 + bmap_total);
132 }
133 }
134
135 isl_vec_free(v);
136 return r;
137 }
138
139 static int tab_add_divs(struct isl_tab *tab, __isl_keep isl_basic_map *bmap,
140 int **div_map)
141 {
142 int i, j;
143 struct isl_vec *vec;
144 unsigned total;
145 unsigned dim;
146
147 if (!bmap)
148 return -1;
149 if (!bmap->n_div)
150 return 0;
151
152 if (!*div_map)
153 *div_map = isl_alloc_array(bmap->ctx, int, bmap->n_div);
154 if (!*div_map)
155 return -1;
156
157 total = isl_basic_map_total_dim(tab->bmap);
158 dim = total - tab->bmap->n_div;
159 vec = isl_vec_alloc(bmap->ctx, 2 + total + bmap->n_div);
160 if (!vec)
161 return -1;
162
163 for (i = 0; i < bmap->n_div; ++i) {
164 isl_seq_cpy(vec->el, bmap->div[i], 2 + dim);
165 isl_seq_clr(vec->el + 2 + dim, tab->bmap->n_div);
166 for (j = 0; j < i; ++j)
167 isl_int_set(vec->el[2 + dim + (*div_map)[j]],
168 bmap->div[i][2 + dim + j]);
169 for (j = 0; j < tab->bmap->n_div; ++j)
170 if (isl_seq_eq(tab->bmap->div[j],
171 vec->el, 2 + dim + tab->bmap->n_div))
172 break;
173 (*div_map)[i] = j;
174 if (j == tab->bmap->n_div) {
175 vec->size = 2 + dim + tab->bmap->n_div;
176 if (isl_tab_add_div(tab, vec, NULL, NULL) < 0)
177 goto error;
178 }
179 }
180
181 isl_vec_free(vec);
182
183 return 0;
184 error:
185 isl_vec_free(vec);
186
187 return -1;
188 }
189
190 /* Freeze all constraints of tableau tab.
191 */
192 static int tab_freeze_constraints(struct isl_tab *tab)
193 {
194 int i;
195
196 for (i = 0; i < tab->n_con; ++i)
197 if (isl_tab_freeze_constraint(tab, i) < 0)
198 return -1;
199
200 return 0;
201 }
202
203 /* Check for redundant constraints starting at offset.
204 * Put the indices of the redundant constraints in index
205 * and return the number of redundant constraints.
206 */
207 static int n_non_redundant(struct isl_tab *tab, int offset, int **index)
208 {
209 int i, n;
210 int n_test = tab->n_con - offset;
211
212 if (isl_tab_detect_redundant(tab) < 0)
213 return -1;
214
215 if (!*index)
216 *index = isl_alloc_array(tab->mat->ctx, int, n_test);
217 if (!*index)
218 return -1;
219
220 for (n = 0, i = 0; i < n_test; ++i) {
221 int r;
222 r = isl_tab_is_redundant(tab, offset + i);
223 if (r < 0)
224 return -1;
225 if (r)
226 continue;
227 (*index)[n++] = i;
228 }
229
230 return n;
231 }
232
233 /* basic_map_collect_diff calls add on each of the pieces of
234 * the set difference between bmap and map until the add method
235 * return a negative value.
236 */
237 struct isl_diff_collector {
238 int (*add)(struct isl_diff_collector *dc,
239 __isl_take isl_basic_map *bmap);
240 };
241
242 /* Compute the set difference between bmap and map and call
243 * dc->add on each of the piece until this function returns
244 * a negative value.
245 * Return 0 on success and -1 on error. dc->add returning
246 * a negative value is treated as an error, but the calling
247 * function can interpret the results based on the state of dc.
248 *
249 * Assumes that both bmap and map have known divs.
250 *
251 * The difference is computed by a backtracking algorithm.
252 * Each level corresponds to a basic map in "map".
253 * When a node in entered for the first time, we check
254 * if the corresonding basic map intersects the current piece
255 * of "bmap". If not, we move to the next level.
256 * Otherwise, we split the current piece into as many
257 * pieces as there are non-redundant constraints of the current
258 * basic map in the intersection. Each of these pieces is
259 * handled by a child of the current node.
260 * In particular, if there are n non-redundant constraints,
261 * then for each 0 <= i < n, a piece is cut off by adding
262 * constraints 0 <= j < i and adding the opposite of constraint i.
263 * If there are no non-redundant constraints, meaning that the current
264 * piece is a subset of the current basic map, then we simply backtrack.
265 *
266 * In the leaves, we check if the remaining piece has any integer points
267 * and if so, pass it along to dc->add. As a special case, if nothing
268 * has been removed when we end up in a leaf, we simply pass along
269 * the original basic map.
270 */
271 static int basic_map_collect_diff(__isl_take isl_basic_map *bmap,
272 __isl_take isl_map *map, struct isl_diff_collector *dc)
273 {
274 int i;
275 int modified;
276 int level;
277 int init;
278 int empty;
279 struct isl_tab *tab = NULL;
280 struct isl_tab_undo **snap = NULL;
281 int *k = NULL;
282 int *n = NULL;
283 int **index = NULL;
284 int **div_map = NULL;
285
286 empty = isl_basic_map_is_empty(bmap);
287 if (empty) {
288 isl_basic_map_free(bmap);
289 isl_map_free(map);
290 return empty < 0 ? -1 : 0;
291 }
292
293 bmap = isl_basic_map_cow(bmap);
294 map = isl_map_cow(map);
295
296 if (!bmap || !map)
297 goto error;
298
299 snap = isl_alloc_array(map->ctx, struct isl_tab_undo *, map->n);
300 k = isl_alloc_array(map->ctx, int, map->n);
301 n = isl_alloc_array(map->ctx, int, map->n);
302 index = isl_calloc_array(map->ctx, int *, map->n);
303 div_map = isl_calloc_array(map->ctx, int *, map->n);
304 if (!snap || !k || !n || !index || !div_map)
305 goto error;
306
307 bmap = isl_basic_map_order_divs(bmap);
308 map = isl_map_order_divs(map);
309
310 tab = isl_tab_from_basic_map(bmap);
311 if (isl_tab_track_bmap(tab, isl_basic_map_copy(bmap)) < 0)
312 goto error;
313
314 modified = 0;
315 level = 0;
316 init = 1;
317
318 while (level >= 0) {
319 if (level >= map->n) {
320 int empty;
321 struct isl_basic_map *bm;
322 if (!modified) {
323 if (dc->add(dc, isl_basic_map_copy(bmap)) < 0)
324 goto error;
325 break;
326 }
327 bm = isl_basic_map_copy(tab->bmap);
328 bm = isl_basic_map_cow(bm);
329 bm = isl_basic_map_update_from_tab(bm, tab);
330 bm = isl_basic_map_simplify(bm);
331 bm = isl_basic_map_finalize(bm);
332 empty = isl_basic_map_is_empty(bm);
333 if (empty)
334 isl_basic_map_free(bm);
335 else if (dc->add(dc, bm) < 0)
336 goto error;
337 if (empty < 0)
338 goto error;
339 level--;
340 init = 0;
341 continue;
342 }
343 if (init) {
344 int offset;
345 struct isl_tab_undo *snap2;
346 snap2 = isl_tab_snap(tab);
347 if (tab_add_divs(tab, map->p[level],
348 &div_map[level]) < 0)
349 goto error;
350 offset = tab->n_con;
351 snap[level] = isl_tab_snap(tab);
352 if (tab_freeze_constraints(tab) < 0)
353 goto error;
354 if (tab_add_constraints(tab, map->p[level],
355 div_map[level]) < 0)
356 goto error;
357 k[level] = 0;
358 n[level] = 0;
359 if (tab->empty) {
360 if (isl_tab_rollback(tab, snap2) < 0)
361 goto error;
362 level++;
363 continue;
364 }
365 modified = 1;
366 n[level] = n_non_redundant(tab, offset, &index[level]);
367 if (n[level] < 0)
368 goto error;
369 if (n[level] == 0) {
370 level--;
371 init = 0;
372 continue;
373 }
374 if (isl_tab_rollback(tab, snap[level]) < 0)
375 goto error;
376 if (tab_add_constraint(tab, map->p[level],
377 div_map[level], index[level][0], 1) < 0)
378 goto error;
379 level++;
380 continue;
381 } else {
382 if (k[level] + 1 >= n[level]) {
383 level--;
384 continue;
385 }
386 if (isl_tab_rollback(tab, snap[level]) < 0)
387 goto error;
388 if (tab_add_constraint(tab, map->p[level],
389 div_map[level],
390 index[level][k[level]], 0) < 0)
391 goto error;
392 snap[level] = isl_tab_snap(tab);
393 k[level]++;
394 if (tab_add_constraint(tab, map->p[level],
395 div_map[level],
396 index[level][k[level]], 1) < 0)
397 goto error;
398 level++;
399 init = 1;
400 continue;
401 }
402 }
403
404 isl_tab_free(tab);
405 free(snap);
406 free(n);
407 free(k);
408 for (i = 0; index && i < map->n; ++i)
409 free(index[i]);
410 free(index);
411 for (i = 0; div_map && i < map->n; ++i)
412 free(div_map[i]);
413 free(div_map);
414
415 isl_basic_map_free(bmap);
416 isl_map_free(map);
417
418 return 0;
419 error:
420 isl_tab_free(tab);
421 free(snap);
422 free(n);
423 free(k);
424 for (i = 0; index && i < map->n; ++i)
425 free(index[i]);
426 free(index);
427 for (i = 0; div_map && i < map->n; ++i)
428 free(div_map[i]);
429 free(div_map);
430 isl_basic_map_free(bmap);
431 isl_map_free(map);
432 return -1;
433 }
434
435 /* A diff collector that actually collects all parts of the
436 * set difference in the field diff.
437 */
438 struct isl_subtract_diff_collector {
439 struct isl_diff_collector dc;
440 struct isl_map *diff;
441 };
442
443 /* isl_subtract_diff_collector callback.
444 */
445 static int basic_map_subtract_add(struct isl_diff_collector *dc,
446 __isl_take isl_basic_map *bmap)
447 {
448 struct isl_subtract_diff_collector *sdc;
449 sdc = (struct isl_subtract_diff_collector *)dc;
450
451 sdc->diff = isl_map_union_disjoint(sdc->diff,
452 isl_map_from_basic_map(bmap));
453
454 return sdc->diff ? 0 : -1;
455 }
456
457 /* Return the set difference between bmap and map.
458 */
459 static __isl_give isl_map *basic_map_subtract(__isl_take isl_basic_map *bmap,
460 __isl_take isl_map *map)
461 {
462 struct isl_subtract_diff_collector sdc;
463 sdc.dc.add = &basic_map_subtract_add;
464 sdc.diff = isl_map_empty_like_basic_map(bmap);
465 if (basic_map_collect_diff(bmap, map, &sdc.dc) < 0) {
466 isl_map_free(sdc.diff);
467 sdc.diff = NULL;
468 }
469 return sdc.diff;
470 }
471
472 /* Return the set difference between map1 and map2.
473 * (U_i A_i) \ (U_j B_j) is computed as U_i (A_i \ (U_j B_j))
474 */
475 struct isl_map *isl_map_subtract(struct isl_map *map1, struct isl_map *map2)
476 {
477 int i;
478 struct isl_map *diff;
479
480 if (!map1 || !map2)
481 goto error;
482
483 isl_assert(map1->ctx, isl_dim_equal(map1->dim, map2->dim), goto error);
484
485 if (isl_map_is_empty(map2)) {
486 isl_map_free(map2);
487 return map1;
488 }
489
490 map1 = isl_map_compute_divs(map1);
491 map2 = isl_map_compute_divs(map2);
492 if (!map1 || !map2)
493 goto error;
494
495 map1 = isl_map_remove_empty_parts(map1);
496 map2 = isl_map_remove_empty_parts(map2);
497
498 diff = isl_map_empty_like(map1);
499 for (i = 0; i < map1->n; ++i) {
500 struct isl_map *d;
501 d = basic_map_subtract(isl_basic_map_copy(map1->p[i]),
502 isl_map_copy(map2));
503 if (ISL_F_ISSET(map1, ISL_MAP_DISJOINT))
504 diff = isl_map_union_disjoint(diff, d);
505 else
506 diff = isl_map_union(diff, d);
507 }
508
509 isl_map_free(map1);
510 isl_map_free(map2);
511
512 return diff;
513 error:
514 isl_map_free(map1);
515 isl_map_free(map2);
516 return NULL;
517 }
518
519 struct isl_set *isl_set_subtract(struct isl_set *set1, struct isl_set *set2)
520 {
521 return (struct isl_set *)
522 isl_map_subtract(
523 (struct isl_map *)set1, (struct isl_map *)set2);
524 }
525
526 /* A diff collector that aborts as soon as its add function is called,
527 * setting empty to 0.
528 */
529 struct isl_is_empty_diff_collector {
530 struct isl_diff_collector dc;
531 int empty;
532 };
533
534 /* isl_is_empty_diff_collector callback.
535 */
536 static int basic_map_is_empty_add(struct isl_diff_collector *dc,
537 __isl_take isl_basic_map *bmap)
538 {
539 struct isl_is_empty_diff_collector *edc;
540 edc = (struct isl_is_empty_diff_collector *)dc;
541
542 edc->empty = 0;
543
544 isl_basic_map_free(bmap);
545 return -1;
546 }
547
548 /* Check if bmap \ map is empty by computing this set difference
549 * and breaking off as soon as the difference is known to be non-empty.
550 */
551 static int basic_map_diff_is_empty(__isl_keep isl_basic_map *bmap,
552 __isl_keep isl_map *map)
553 {
554 int r;
555 struct isl_is_empty_diff_collector edc;
556
557 r = isl_basic_map_fast_is_empty(bmap);
558 if (r)
559 return r;
560
561 edc.dc.add = &basic_map_is_empty_add;
562 edc.empty = 1;
563 r = basic_map_collect_diff(isl_basic_map_copy(bmap),
564 isl_map_copy(map), &edc.dc);
565 if (!edc.empty)
566 return 0;
567
568 return r < 0 ? -1 : 1;
569 }
570
571 /* Check if map1 \ map2 is empty by checking if the set difference is empty
572 * for each of the basic maps in map1.
573 */
574 static int map_diff_is_empty(__isl_keep isl_map *map1, __isl_keep isl_map *map2)
575 {
576 int i;
577 int is_empty = 1;
578
579 if (!map1 || !map2)
580 return -1;
581
582 for (i = 0; i < map1->n; ++i) {
583 is_empty = basic_map_diff_is_empty(map1->p[i], map2);
584 if (is_empty < 0 || !is_empty)
585 break;
586 }
587
588 return is_empty;
589 }
590
591 /* Return 1 if "bmap" contains a single element.
592 */
593 int isl_basic_map_is_singleton(__isl_keep isl_basic_map *bmap)
594 {
595 if (!bmap)
596 return -1;
597 if (bmap->n_div)
598 return 0;
599 if (bmap->n_ineq)
600 return 0;
601 return bmap->n_eq == isl_basic_map_total_dim(bmap);
602 }
603
604 /* Return 1 if "map" contains a single element.
605 */
606 int isl_map_is_singleton(__isl_keep isl_map *map)
607 {
608 if (!map)
609 return -1;
610 if (map->n != 1)
611 return 0;
612
613 return isl_basic_map_is_singleton(map->p[0]);
614 }
615
616 /* Given a singleton basic map, extract the single element
617 * as an isl_point.
618 */
619 static __isl_give isl_point *singleton_extract_point(
620 __isl_keep isl_basic_map *bmap)
621 {
622 int i, j;
623 unsigned dim;
624 struct isl_vec *point;
625 isl_int m;
626
627 if (!bmap)
628 return NULL;
629
630 dim = isl_basic_map_total_dim(bmap);
631 isl_assert(bmap->ctx, bmap->n_eq == dim, return NULL);
632 point = isl_vec_alloc(bmap->ctx, 1 + dim);
633 if (!point)
634 return NULL;
635
636 isl_int_init(m);
637
638 isl_int_set_si(point->el[0], 1);
639 for (j = 0; j < bmap->n_eq; ++j) {
640 int s;
641 int i = dim - 1 - j;
642 isl_assert(bmap->ctx,
643 isl_seq_first_non_zero(bmap->eq[j] + 1, i) == -1,
644 goto error);
645 isl_assert(bmap->ctx,
646 isl_int_is_one(bmap->eq[j][1 + i]) ||
647 isl_int_is_negone(bmap->eq[j][1 + i]),
648 goto error);
649 isl_assert(bmap->ctx,
650 isl_seq_first_non_zero(bmap->eq[j]+1+i+1, dim-i-1) == -1,
651 goto error);
652
653 isl_int_gcd(m, point->el[0], bmap->eq[j][1 + i]);
654 isl_int_divexact(m, bmap->eq[j][1 + i], m);
655 isl_int_abs(m, m);
656 isl_seq_scale(point->el, point->el, m, 1 + i);
657 isl_int_divexact(m, point->el[0], bmap->eq[j][1 + i]);
658 isl_int_neg(m, m);
659 isl_int_mul(point->el[1 + i], m, bmap->eq[j][0]);
660 }
661
662 isl_int_clear(m);
663 return isl_point_alloc(isl_basic_map_get_dim(bmap), point);
664 error:
665 isl_int_clear(m);
666 isl_vec_free(point);
667 return NULL;
668 }
669
670 /* Return 1 is the singleton map "map1" is a subset of "map2",
671 * i.e., if the single element of "map1" is also an element of "map2".
672 */
673 static int map_is_singleton_subset(__isl_keep isl_map *map1,
674 __isl_keep isl_map *map2)
675 {
676 int i;
677 int is_subset = 0;
678 struct isl_point *point;
679
680 if (!map1 || !map2)
681 return -1;
682 if (map1->n != 1)
683 return -1;
684
685 point = singleton_extract_point(map1->p[0]);
686 if (!point)
687 return -1;
688
689 for (i = 0; i < map2->n; ++i) {
690 is_subset = isl_basic_map_contains_point(map2->p[i], point);
691 if (is_subset)
692 break;
693 }
694
695 isl_point_free(point);
696 return is_subset;
697 }
698
699 int isl_map_is_subset(struct isl_map *map1, struct isl_map *map2)
700 {
701 int is_subset = 0;
702 struct isl_map *diff;
703
704 if (!map1 || !map2)
705 return -1;
706
707 if (isl_map_is_empty(map1))
708 return 1;
709
710 if (isl_map_is_empty(map2))
711 return 0;
712
713 if (isl_map_fast_is_universe(map2))
714 return 1;
715
716 map1 = isl_map_compute_divs(isl_map_copy(map1));
717 map2 = isl_map_compute_divs(isl_map_copy(map2));
718 if (isl_map_is_singleton(map1)) {
719 is_subset = map_is_singleton_subset(map1, map2);
720 isl_map_free(map1);
721 isl_map_free(map2);
722 return is_subset;
723 }
724 is_subset = map_diff_is_empty(map1, map2);
725 isl_map_free(map1);
726 isl_map_free(map2);
727
728 return is_subset;
729 }
730
731 int isl_set_is_subset(struct isl_set *set1, struct isl_set *set2)
732 {
733 return isl_map_is_subset(
734 (struct isl_map *)set1, (struct isl_map *)set2);
735 }
736
737 __isl_give isl_map *isl_map_make_disjoint(__isl_take isl_map *map)
738 {
739 int i;
740 struct isl_subtract_diff_collector sdc;
741 sdc.dc.add = &basic_map_subtract_add;
742
743 if (!map)
744 return NULL;
745 if (ISL_F_ISSET(map, ISL_MAP_DISJOINT))
746 return map;
747 if (map->n <= 1)
748 return map;
749
750 map = isl_map_compute_divs(map);
751 map = isl_map_remove_empty_parts(map);
752
753 if (!map || map->n <= 1)
754 return map;
755
756 sdc.diff = isl_map_from_basic_map(isl_basic_map_copy(map->p[0]));
757
758 for (i = 1; i < map->n; ++i) {
759 struct isl_basic_map *bmap = isl_basic_map_copy(map->p[i]);
760 struct isl_map *copy = isl_map_copy(sdc.diff);
761 if (basic_map_collect_diff(bmap, copy, &sdc.dc) < 0) {
762 isl_map_free(sdc.diff);
763 sdc.diff = NULL;
764 break;
765 }
766 }
767
768 isl_map_free(map);
769
770 return sdc.diff;
771 }
772
773 __isl_give isl_set *isl_set_make_disjoint(__isl_take isl_set *set)
774 {
775 return (struct isl_set *)isl_map_make_disjoint((struct isl_map *)set);
776 }
777
778 __isl_give isl_set *isl_set_complement(__isl_take isl_set *set)
779 {
780 isl_set *universe;
781
782 if (!set)
783 return NULL;
784
785 universe = isl_set_universe(isl_set_get_dim(set));
786
787 return isl_set_subtract(universe, set);
788 }
Integer set library