2 * Copyright 2008-2009 Katholieke Universiteit Leuven
4 * Use of this software is governed by the GNU LGPLv2.1 license
6 * Written by Sven Verdoolaege, K.U.Leuven, Departement
7 * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
10 #include <isl_map_private.h>
15 #include <isl_point_private.h>
17 static void expand_constraint(isl_vec
*v
, unsigned dim
,
18 isl_int
*c
, int *div_map
, unsigned n_div
)
22 isl_seq_cpy(v
->el
, c
, 1 + dim
);
23 isl_seq_clr(v
->el
+ 1 + dim
, v
->size
- (1 + dim
));
25 for (i
= 0; i
< n_div
; ++i
)
26 isl_int_set(v
->el
[1 + dim
+ div_map
[i
]], c
[1 + dim
+ i
]);
29 /* Add all constraints of bmap to tab. The equalities of bmap
30 * are added as a pair of inequalities.
32 static int tab_add_constraints(struct isl_tab
*tab
,
33 __isl_keep isl_basic_map
*bmap
, int *div_map
)
44 tab_total
= isl_basic_map_total_dim(tab
->bmap
);
45 bmap_total
= isl_basic_map_total_dim(bmap
);
46 dim
= isl_space_dim(tab
->bmap
->dim
, isl_dim_all
);
48 if (isl_tab_extend_cons(tab
, 2 * bmap
->n_eq
+ bmap
->n_ineq
) < 0)
51 v
= isl_vec_alloc(bmap
->ctx
, 1 + tab_total
);
55 for (i
= 0; i
< bmap
->n_eq
; ++i
) {
56 expand_constraint(v
, dim
, bmap
->eq
[i
], div_map
, bmap
->n_div
);
57 if (isl_tab_add_ineq(tab
, v
->el
) < 0)
59 isl_seq_neg(bmap
->eq
[i
], bmap
->eq
[i
], 1 + bmap_total
);
60 expand_constraint(v
, dim
, bmap
->eq
[i
], div_map
, bmap
->n_div
);
61 if (isl_tab_add_ineq(tab
, v
->el
) < 0)
63 isl_seq_neg(bmap
->eq
[i
], bmap
->eq
[i
], 1 + bmap_total
);
68 for (i
= 0; i
< bmap
->n_ineq
; ++i
) {
69 expand_constraint(v
, dim
, bmap
->ineq
[i
], div_map
, bmap
->n_div
);
70 if (isl_tab_add_ineq(tab
, v
->el
) < 0)
83 /* Add a specific constraint of bmap (or its opposite) to tab.
84 * The position of the constraint is specified by "c", where
85 * the equalities of bmap are counted twice, once for the inequality
86 * that is equal to the equality, and once for its negation.
88 static int tab_add_constraint(struct isl_tab
*tab
,
89 __isl_keep isl_basic_map
*bmap
, int *div_map
, int c
, int oppose
)
100 tab_total
= isl_basic_map_total_dim(tab
->bmap
);
101 bmap_total
= isl_basic_map_total_dim(bmap
);
102 dim
= isl_space_dim(tab
->bmap
->dim
, isl_dim_all
);
104 v
= isl_vec_alloc(bmap
->ctx
, 1 + tab_total
);
108 if (c
< 2 * bmap
->n_eq
) {
109 if ((c
% 2) != oppose
)
110 isl_seq_neg(bmap
->eq
[c
/2], bmap
->eq
[c
/2],
113 isl_int_sub_ui(bmap
->eq
[c
/2][0], bmap
->eq
[c
/2][0], 1);
114 expand_constraint(v
, dim
, bmap
->eq
[c
/2], div_map
, bmap
->n_div
);
115 r
= isl_tab_add_ineq(tab
, v
->el
);
117 isl_int_add_ui(bmap
->eq
[c
/2][0], bmap
->eq
[c
/2][0], 1);
118 if ((c
% 2) != oppose
)
119 isl_seq_neg(bmap
->eq
[c
/2], bmap
->eq
[c
/2],
124 isl_seq_neg(bmap
->ineq
[c
], bmap
->ineq
[c
],
126 isl_int_sub_ui(bmap
->ineq
[c
][0], bmap
->ineq
[c
][0], 1);
128 expand_constraint(v
, dim
, bmap
->ineq
[c
], div_map
, bmap
->n_div
);
129 r
= isl_tab_add_ineq(tab
, v
->el
);
131 isl_int_add_ui(bmap
->ineq
[c
][0], bmap
->ineq
[c
][0], 1);
132 isl_seq_neg(bmap
->ineq
[c
], bmap
->ineq
[c
],
141 static int tab_add_divs(struct isl_tab
*tab
, __isl_keep isl_basic_map
*bmap
,
155 *div_map
= isl_alloc_array(bmap
->ctx
, int, bmap
->n_div
);
159 total
= isl_basic_map_total_dim(tab
->bmap
);
160 dim
= total
- tab
->bmap
->n_div
;
161 vec
= isl_vec_alloc(bmap
->ctx
, 2 + total
+ bmap
->n_div
);
165 for (i
= 0; i
< bmap
->n_div
; ++i
) {
166 isl_seq_cpy(vec
->el
, bmap
->div
[i
], 2 + dim
);
167 isl_seq_clr(vec
->el
+ 2 + dim
, tab
->bmap
->n_div
);
168 for (j
= 0; j
< i
; ++j
)
169 isl_int_set(vec
->el
[2 + dim
+ (*div_map
)[j
]],
170 bmap
->div
[i
][2 + dim
+ j
]);
171 for (j
= 0; j
< tab
->bmap
->n_div
; ++j
)
172 if (isl_seq_eq(tab
->bmap
->div
[j
],
173 vec
->el
, 2 + dim
+ tab
->bmap
->n_div
))
176 if (j
== tab
->bmap
->n_div
) {
177 vec
->size
= 2 + dim
+ tab
->bmap
->n_div
;
178 if (isl_tab_add_div(tab
, vec
, NULL
, NULL
) < 0)
192 /* Freeze all constraints of tableau tab.
194 static int tab_freeze_constraints(struct isl_tab
*tab
)
198 for (i
= 0; i
< tab
->n_con
; ++i
)
199 if (isl_tab_freeze_constraint(tab
, i
) < 0)
205 /* Check for redundant constraints starting at offset.
206 * Put the indices of the redundant constraints in index
207 * and return the number of redundant constraints.
209 static int n_non_redundant(isl_ctx
*ctx
, struct isl_tab
*tab
,
210 int offset
, int **index
)
213 int n_test
= tab
->n_con
- offset
;
215 if (isl_tab_detect_redundant(tab
) < 0)
219 *index
= isl_alloc_array(ctx
, int, n_test
);
223 for (n
= 0, i
= 0; i
< n_test
; ++i
) {
225 r
= isl_tab_is_redundant(tab
, offset
+ i
);
236 /* basic_map_collect_diff calls add on each of the pieces of
237 * the set difference between bmap and map until the add method
238 * return a negative value.
240 struct isl_diff_collector
{
241 int (*add
)(struct isl_diff_collector
*dc
,
242 __isl_take isl_basic_map
*bmap
);
245 /* Compute the set difference between bmap and map and call
246 * dc->add on each of the piece until this function returns
248 * Return 0 on success and -1 on error. dc->add returning
249 * a negative value is treated as an error, but the calling
250 * function can interpret the results based on the state of dc.
252 * Assumes that map has known divs.
254 * The difference is computed by a backtracking algorithm.
255 * Each level corresponds to a basic map in "map".
256 * When a node in entered for the first time, we check
257 * if the corresonding basic map intersects the current piece
258 * of "bmap". If not, we move to the next level.
259 * Otherwise, we split the current piece into as many
260 * pieces as there are non-redundant constraints of the current
261 * basic map in the intersection. Each of these pieces is
262 * handled by a child of the current node.
263 * In particular, if there are n non-redundant constraints,
264 * then for each 0 <= i < n, a piece is cut off by adding
265 * constraints 0 <= j < i and adding the opposite of constraint i.
266 * If there are no non-redundant constraints, meaning that the current
267 * piece is a subset of the current basic map, then we simply backtrack.
269 * In the leaves, we check if the remaining piece has any integer points
270 * and if so, pass it along to dc->add. As a special case, if nothing
271 * has been removed when we end up in a leaf, we simply pass along
272 * the original basic map.
274 static int basic_map_collect_diff(__isl_take isl_basic_map
*bmap
,
275 __isl_take isl_map
*map
, struct isl_diff_collector
*dc
)
283 struct isl_tab
*tab
= NULL
;
284 struct isl_tab_undo
**snap
= NULL
;
288 int **div_map
= NULL
;
290 empty
= isl_basic_map_is_empty(bmap
);
292 isl_basic_map_free(bmap
);
294 return empty
< 0 ? -1 : 0;
297 bmap
= isl_basic_map_cow(bmap
);
298 map
= isl_map_cow(map
);
304 snap
= isl_alloc_array(map
->ctx
, struct isl_tab_undo
*, map
->n
);
305 k
= isl_alloc_array(map
->ctx
, int, map
->n
);
306 n
= isl_alloc_array(map
->ctx
, int, map
->n
);
307 index
= isl_calloc_array(map
->ctx
, int *, map
->n
);
308 div_map
= isl_calloc_array(map
->ctx
, int *, map
->n
);
309 if (!snap
|| !k
|| !n
|| !index
|| !div_map
)
312 bmap
= isl_basic_map_order_divs(bmap
);
313 map
= isl_map_order_divs(map
);
315 tab
= isl_tab_from_basic_map(bmap
, 1);
322 if (level
>= map
->n
) {
324 struct isl_basic_map
*bm
;
326 if (dc
->add(dc
, isl_basic_map_copy(bmap
)) < 0)
330 bm
= isl_basic_map_copy(tab
->bmap
);
331 bm
= isl_basic_map_cow(bm
);
332 bm
= isl_basic_map_update_from_tab(bm
, tab
);
333 bm
= isl_basic_map_simplify(bm
);
334 bm
= isl_basic_map_finalize(bm
);
335 empty
= isl_basic_map_is_empty(bm
);
337 isl_basic_map_free(bm
);
338 else if (dc
->add(dc
, bm
) < 0)
348 struct isl_tab_undo
*snap2
;
349 snap2
= isl_tab_snap(tab
);
350 if (tab_add_divs(tab
, map
->p
[level
],
351 &div_map
[level
]) < 0)
354 snap
[level
] = isl_tab_snap(tab
);
355 if (tab_freeze_constraints(tab
) < 0)
357 if (tab_add_constraints(tab
, map
->p
[level
],
363 if (isl_tab_rollback(tab
, snap2
) < 0)
369 n
[level
] = n_non_redundant(ctx
, tab
, offset
,
378 if (isl_tab_rollback(tab
, snap
[level
]) < 0)
380 if (tab_add_constraint(tab
, map
->p
[level
],
381 div_map
[level
], index
[level
][0], 1) < 0)
386 if (k
[level
] + 1 >= n
[level
]) {
390 if (isl_tab_rollback(tab
, snap
[level
]) < 0)
392 if (tab_add_constraint(tab
, map
->p
[level
],
394 index
[level
][k
[level
]], 0) < 0)
396 snap
[level
] = isl_tab_snap(tab
);
398 if (tab_add_constraint(tab
, map
->p
[level
],
400 index
[level
][k
[level
]], 1) < 0)
412 for (i
= 0; index
&& i
< map
->n
; ++i
)
415 for (i
= 0; div_map
&& i
< map
->n
; ++i
)
419 isl_basic_map_free(bmap
);
428 for (i
= 0; index
&& i
< map
->n
; ++i
)
431 for (i
= 0; div_map
&& i
< map
->n
; ++i
)
434 isl_basic_map_free(bmap
);
439 /* A diff collector that actually collects all parts of the
440 * set difference in the field diff.
442 struct isl_subtract_diff_collector
{
443 struct isl_diff_collector dc
;
444 struct isl_map
*diff
;
447 /* isl_subtract_diff_collector callback.
449 static int basic_map_subtract_add(struct isl_diff_collector
*dc
,
450 __isl_take isl_basic_map
*bmap
)
452 struct isl_subtract_diff_collector
*sdc
;
453 sdc
= (struct isl_subtract_diff_collector
*)dc
;
455 sdc
->diff
= isl_map_union_disjoint(sdc
->diff
,
456 isl_map_from_basic_map(bmap
));
458 return sdc
->diff
? 0 : -1;
461 /* Return the set difference between bmap and map.
463 static __isl_give isl_map
*basic_map_subtract(__isl_take isl_basic_map
*bmap
,
464 __isl_take isl_map
*map
)
466 struct isl_subtract_diff_collector sdc
;
467 sdc
.dc
.add
= &basic_map_subtract_add
;
468 sdc
.diff
= isl_map_empty_like_basic_map(bmap
);
469 if (basic_map_collect_diff(bmap
, map
, &sdc
.dc
) < 0) {
470 isl_map_free(sdc
.diff
);
476 /* Return the set difference between map1 and map2.
477 * (U_i A_i) \ (U_j B_j) is computed as U_i (A_i \ (U_j B_j))
479 static __isl_give isl_map
*map_subtract( __isl_take isl_map
*map1
,
480 __isl_take isl_map
*map2
)
483 struct isl_map
*diff
;
488 isl_assert(map1
->ctx
, isl_space_is_equal(map1
->dim
, map2
->dim
), goto error
);
490 if (isl_map_is_empty(map2
)) {
495 map1
= isl_map_compute_divs(map1
);
496 map2
= isl_map_compute_divs(map2
);
500 map1
= isl_map_remove_empty_parts(map1
);
501 map2
= isl_map_remove_empty_parts(map2
);
503 diff
= isl_map_empty_like(map1
);
504 for (i
= 0; i
< map1
->n
; ++i
) {
506 d
= basic_map_subtract(isl_basic_map_copy(map1
->p
[i
]),
508 if (ISL_F_ISSET(map1
, ISL_MAP_DISJOINT
))
509 diff
= isl_map_union_disjoint(diff
, d
);
511 diff
= isl_map_union(diff
, d
);
524 __isl_give isl_map
*isl_map_subtract( __isl_take isl_map
*map1
,
525 __isl_take isl_map
*map2
)
527 return isl_map_align_params_map_map_and(map1
, map2
, &map_subtract
);
530 struct isl_set
*isl_set_subtract(struct isl_set
*set1
, struct isl_set
*set2
)
532 return (struct isl_set
*)
534 (struct isl_map
*)set1
, (struct isl_map
*)set2
);
537 /* Remove the elements of "dom" from the domain of "map".
539 static __isl_give isl_map
*map_subtract_domain(__isl_take isl_map
*map
,
540 __isl_take isl_set
*dom
)
544 if (!isl_map_compatible_domain(map
, dom
))
545 isl_die(isl_set_get_ctx(dom
), isl_error_invalid
,
546 "incompatible spaces", goto error
);
548 ext_dom
= isl_map_universe(isl_map_get_space(map
));
549 ext_dom
= isl_map_intersect_domain(ext_dom
, dom
);
550 return isl_map_subtract(map
, ext_dom
);
557 __isl_give isl_map
*isl_map_subtract_domain(__isl_take isl_map
*map
,
558 __isl_take isl_set
*dom
)
560 return isl_map_align_params_map_map_and(map
, dom
, &map_subtract_domain
);
563 /* Remove the elements of "dom" from the range of "map".
565 static __isl_give isl_map
*map_subtract_range(__isl_take isl_map
*map
,
566 __isl_take isl_set
*dom
)
570 if (!isl_map_compatible_range(map
, dom
))
571 isl_die(isl_set_get_ctx(dom
), isl_error_invalid
,
572 "incompatible spaces", goto error
);
574 ext_dom
= isl_map_universe(isl_map_get_space(map
));
575 ext_dom
= isl_map_intersect_range(ext_dom
, dom
);
576 return isl_map_subtract(map
, ext_dom
);
583 __isl_give isl_map
*isl_map_subtract_range(__isl_take isl_map
*map
,
584 __isl_take isl_set
*dom
)
586 return isl_map_align_params_map_map_and(map
, dom
, &map_subtract_range
);
589 /* A diff collector that aborts as soon as its add function is called,
590 * setting empty to 0.
592 struct isl_is_empty_diff_collector
{
593 struct isl_diff_collector dc
;
597 /* isl_is_empty_diff_collector callback.
599 static int basic_map_is_empty_add(struct isl_diff_collector
*dc
,
600 __isl_take isl_basic_map
*bmap
)
602 struct isl_is_empty_diff_collector
*edc
;
603 edc
= (struct isl_is_empty_diff_collector
*)dc
;
607 isl_basic_map_free(bmap
);
611 /* Check if bmap \ map is empty by computing this set difference
612 * and breaking off as soon as the difference is known to be non-empty.
614 static int basic_map_diff_is_empty(__isl_keep isl_basic_map
*bmap
,
615 __isl_keep isl_map
*map
)
618 struct isl_is_empty_diff_collector edc
;
620 r
= isl_basic_map_plain_is_empty(bmap
);
624 edc
.dc
.add
= &basic_map_is_empty_add
;
626 r
= basic_map_collect_diff(isl_basic_map_copy(bmap
),
627 isl_map_copy(map
), &edc
.dc
);
631 return r
< 0 ? -1 : 1;
634 /* Check if map1 \ map2 is empty by checking if the set difference is empty
635 * for each of the basic maps in map1.
637 static int map_diff_is_empty(__isl_keep isl_map
*map1
, __isl_keep isl_map
*map2
)
645 for (i
= 0; i
< map1
->n
; ++i
) {
646 is_empty
= basic_map_diff_is_empty(map1
->p
[i
], map2
);
647 if (is_empty
< 0 || !is_empty
)
654 /* Return 1 if "bmap" contains a single element.
656 int isl_basic_map_plain_is_singleton(__isl_keep isl_basic_map
*bmap
)
664 return bmap
->n_eq
== isl_basic_map_total_dim(bmap
);
667 /* Return 1 if "map" contains a single element.
669 int isl_map_plain_is_singleton(__isl_keep isl_map
*map
)
676 return isl_basic_map_plain_is_singleton(map
->p
[0]);
679 /* Given a singleton basic map, extract the single element
682 static __isl_give isl_point
*singleton_extract_point(
683 __isl_keep isl_basic_map
*bmap
)
687 struct isl_vec
*point
;
693 dim
= isl_basic_map_total_dim(bmap
);
694 isl_assert(bmap
->ctx
, bmap
->n_eq
== dim
, return NULL
);
695 point
= isl_vec_alloc(bmap
->ctx
, 1 + dim
);
701 isl_int_set_si(point
->el
[0], 1);
702 for (j
= 0; j
< bmap
->n_eq
; ++j
) {
704 isl_assert(bmap
->ctx
,
705 isl_seq_first_non_zero(bmap
->eq
[j
] + 1, i
) == -1,
707 isl_assert(bmap
->ctx
,
708 isl_int_is_one(bmap
->eq
[j
][1 + i
]) ||
709 isl_int_is_negone(bmap
->eq
[j
][1 + i
]),
711 isl_assert(bmap
->ctx
,
712 isl_seq_first_non_zero(bmap
->eq
[j
]+1+i
+1, dim
-i
-1) == -1,
715 isl_int_gcd(m
, point
->el
[0], bmap
->eq
[j
][1 + i
]);
716 isl_int_divexact(m
, bmap
->eq
[j
][1 + i
], m
);
718 isl_seq_scale(point
->el
, point
->el
, m
, 1 + i
);
719 isl_int_divexact(m
, point
->el
[0], bmap
->eq
[j
][1 + i
]);
721 isl_int_mul(point
->el
[1 + i
], m
, bmap
->eq
[j
][0]);
725 return isl_point_alloc(isl_basic_map_get_space(bmap
), point
);
732 /* Return 1 is the singleton map "map1" is a subset of "map2",
733 * i.e., if the single element of "map1" is also an element of "map2".
734 * Assumes "map2" has known divs.
736 static int map_is_singleton_subset(__isl_keep isl_map
*map1
,
737 __isl_keep isl_map
*map2
)
741 struct isl_point
*point
;
748 point
= singleton_extract_point(map1
->p
[0]);
752 for (i
= 0; i
< map2
->n
; ++i
) {
753 is_subset
= isl_basic_map_contains_point(map2
->p
[i
], point
);
758 isl_point_free(point
);
762 static int map_is_subset(__isl_keep isl_map
*map1
, __isl_keep isl_map
*map2
)
769 if (!isl_map_has_equal_space(map1
, map2
))
772 if (isl_map_is_empty(map1
))
775 if (isl_map_is_empty(map2
))
778 if (isl_map_plain_is_universe(map2
))
781 map2
= isl_map_compute_divs(isl_map_copy(map2
));
782 if (isl_map_plain_is_singleton(map1
)) {
783 is_subset
= map_is_singleton_subset(map1
, map2
);
787 is_subset
= map_diff_is_empty(map1
, map2
);
793 int isl_map_is_subset(__isl_keep isl_map
*map1
, __isl_keep isl_map
*map2
)
795 return isl_map_align_params_map_map_and_test(map1
, map2
,
799 int isl_set_is_subset(struct isl_set
*set1
, struct isl_set
*set2
)
801 return isl_map_is_subset(
802 (struct isl_map
*)set1
, (struct isl_map
*)set2
);
805 __isl_give isl_map
*isl_map_make_disjoint(__isl_take isl_map
*map
)
808 struct isl_subtract_diff_collector sdc
;
809 sdc
.dc
.add
= &basic_map_subtract_add
;
813 if (ISL_F_ISSET(map
, ISL_MAP_DISJOINT
))
818 map
= isl_map_compute_divs(map
);
819 map
= isl_map_remove_empty_parts(map
);
821 if (!map
|| map
->n
<= 1)
824 sdc
.diff
= isl_map_from_basic_map(isl_basic_map_copy(map
->p
[0]));
826 for (i
= 1; i
< map
->n
; ++i
) {
827 struct isl_basic_map
*bmap
= isl_basic_map_copy(map
->p
[i
]);
828 struct isl_map
*copy
= isl_map_copy(sdc
.diff
);
829 if (basic_map_collect_diff(bmap
, copy
, &sdc
.dc
) < 0) {
830 isl_map_free(sdc
.diff
);
841 __isl_give isl_set
*isl_set_make_disjoint(__isl_take isl_set
*set
)
843 return (struct isl_set
*)isl_map_make_disjoint((struct isl_map
*)set
);
846 __isl_give isl_map
*isl_map_complement(__isl_take isl_map
*map
)
853 universe
= isl_map_universe(isl_map_get_space(map
));
855 return isl_map_subtract(universe
, map
);
858 __isl_give isl_set
*isl_set_complement(__isl_take isl_set
*set
)
860 return isl_map_complement(set
);