/*
* Copyright 2008-2009 Katholieke Universiteit Leuven
* Copyright 2010 INRIA Saclay
+ * Copyright 2012 Ecole Normale Superieure
*
- * Use of this software is governed by the GNU LGPLv2.1 license
+ * Use of this software is governed by the MIT license
*
* Written by Sven Verdoolaege, K.U.Leuven, Departement
* Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
* and INRIA Saclay - Ile-de-France, Parc Club Orsay Universite,
* ZAC des vignes, 4 rue Jacques Monod, 91893 Orsay, France
+ * and Ecole Normale Superieure, 45 rue d’Ulm, 75230 Paris, France
*/
#include "isl_map_private.h"
#include <isl/options.h>
#include "isl_tab.h"
#include <isl_mat_private.h>
+#include <isl_local_space_private.h>
#define STATUS_ERROR -1
#define STATUS_REDUNDANT 1
}
/* Compute the position of the inequalities of basic map "bmap_i"
- * (also represented by "tab_i") with respect to the basic map
+ * (also represented by "tab_i", if not NULL) with respect to the basic map
* represented by "tab_j".
*/
static int *ineq_status_in(__isl_keep isl_basic_map *bmap_i,
int *ineq = isl_calloc_array(bmap_i->ctx, int, bmap_i->n_ineq);
for (k = 0; k < bmap_i->n_ineq; ++k) {
- if (isl_tab_is_redundant(tab_i, n_eq + k)) {
+ if (tab_i && isl_tab_is_redundant(tab_i, n_eq + k)) {
ineq[k] = STATUS_REDUNDANT;
continue;
}
* can be represented by a single basic map.
* If so, replace the pair by the single basic map and return 1.
* Otherwise, return 0;
+ * The two basic maps are assumed to live in the same local space.
*
* We first check the effect of each constraint of one basic map
* on the other basic map.
* corresponding to the basic maps. When the basic maps are dropped
* or combined, the tableaus are modified accordingly.
*/
-static int coalesce_pair(struct isl_map *map, int i, int j,
+static int coalesce_local_pair(__isl_keep isl_map *map, int i, int j,
struct isl_tab **tabs)
{
int changed = 0;
return -1;
}
+/* Do the two basic maps live in the same local space, i.e.,
+ * do they have the same (known) divs?
+ * If either basic map has any unknown divs, then we can only assume
+ * that they do not live in the same local space.
+ */
+static int same_divs(__isl_keep isl_basic_map *bmap1,
+ __isl_keep isl_basic_map *bmap2)
+{
+ int i;
+ int known;
+ int total;
+
+ if (!bmap1 || !bmap2)
+ return -1;
+ if (bmap1->n_div != bmap2->n_div)
+ return 0;
+
+ if (bmap1->n_div == 0)
+ return 1;
+
+ known = isl_basic_map_divs_known(bmap1);
+ if (known < 0 || !known)
+ return known;
+ known = isl_basic_map_divs_known(bmap2);
+ if (known < 0 || !known)
+ return known;
+
+ total = isl_basic_map_total_dim(bmap1);
+ for (i = 0; i < bmap1->n_div; ++i)
+ if (!isl_seq_eq(bmap1->div[i], bmap2->div[i], 2 + total))
+ return 0;
+
+ return 1;
+}
+
+/* Given two basic maps "i" and "j", where the divs of "i" form a subset
+ * of those of "j", check if basic map "j" is a subset of basic map "i"
+ * and, if so, drop basic map "j".
+ *
+ * We first expand the divs of basic map "i" to match those of basic map "j",
+ * using the divs and expansion computed by the caller.
+ * Then we check if all constraints of the expanded "i" are valid for "j".
+ */
+static int coalesce_subset(__isl_keep isl_map *map, int i, int j,
+ struct isl_tab **tabs, __isl_keep isl_mat *div, int *exp)
+{
+ isl_basic_map *bmap;
+ int changed = 0;
+ int *eq_i = NULL;
+ int *ineq_i = NULL;
+
+ bmap = isl_basic_map_copy(map->p[i]);
+ bmap = isl_basic_set_expand_divs(bmap, isl_mat_copy(div), exp);
+
+ if (!bmap)
+ goto error;
+
+ eq_i = eq_status_in(bmap, tabs[j]);
+ if (!eq_i)
+ goto error;
+ if (any(eq_i, 2 * bmap->n_eq, STATUS_ERROR))
+ goto error;
+ if (any(eq_i, 2 * bmap->n_eq, STATUS_SEPARATE))
+ goto done;
+
+ ineq_i = ineq_status_in(bmap, NULL, tabs[j]);
+ if (!ineq_i)
+ goto error;
+ if (any(ineq_i, bmap->n_ineq, STATUS_ERROR))
+ goto error;
+ if (any(ineq_i, bmap->n_ineq, STATUS_SEPARATE))
+ goto done;
+
+ if (all(eq_i, 2 * map->p[i]->n_eq, STATUS_VALID) &&
+ all(ineq_i, map->p[i]->n_ineq, STATUS_VALID)) {
+ drop(map, j, tabs);
+ changed = 1;
+ }
+
+done:
+ isl_basic_map_free(bmap);
+ free(eq_i);
+ free(ineq_i);
+ return 0;
+error:
+ isl_basic_map_free(bmap);
+ free(eq_i);
+ free(ineq_i);
+ return -1;
+}
+
+/* Check if the basic map "j" is a subset of basic map "i",
+ * assuming that "i" has fewer divs that "j".
+ * If not, then we change the order.
+ *
+ * If the two basic maps have the same number of divs, then
+ * they must necessarily be different. Otherwise, we would have
+ * called coalesce_local_pair. We therefore don't do try anyhing
+ * in this case.
+ *
+ * We first check if the divs of "i" are all known and form a subset
+ * of those of "j". If so, we pass control over to coalesce_subset.
+ */
+static int check_coalesce_subset(__isl_keep isl_map *map, int i, int j,
+ struct isl_tab **tabs)
+{
+ int known;
+ isl_mat *div_i, *div_j, *div;
+ int *exp1 = NULL;
+ int *exp2 = NULL;
+ isl_ctx *ctx;
+ int subset;
+
+ if (map->p[i]->n_div == map->p[j]->n_div)
+ return 0;
+ if (map->p[j]->n_div < map->p[i]->n_div)
+ return check_coalesce_subset(map, j, i, tabs);
+
+ known = isl_basic_map_divs_known(map->p[i]);
+ if (known < 0 || !known)
+ return known;
+
+ ctx = isl_map_get_ctx(map);
+
+ div_i = isl_basic_map_get_divs(map->p[i]);
+ div_j = isl_basic_map_get_divs(map->p[j]);
+
+ if (!div_i || !div_j)
+ goto error;
+
+ exp1 = isl_alloc_array(ctx, int, div_i->n_row);
+ exp2 = isl_alloc_array(ctx, int, div_j->n_row);
+ if (!exp1 || !exp2)
+ goto error;
+
+ div = isl_merge_divs(div_i, div_j, exp1, exp2);
+ if (!div)
+ goto error;
+
+ if (div->n_row == div_j->n_row)
+ subset = coalesce_subset(map, i, j, tabs, div, exp1);
+ else
+ subset = 0;
+
+ isl_mat_free(div);
+
+ isl_mat_free(div_i);
+ isl_mat_free(div_j);
+
+ free(exp2);
+ free(exp1);
+
+ return subset;
+error:
+ isl_mat_free(div_i);
+ isl_mat_free(div_j);
+ free(exp1);
+ free(exp2);
+ return -1;
+}
+
+/* Check if the union of the given pair of basic maps
+ * can be represented by a single basic map.
+ * If so, replace the pair by the single basic map and return 1.
+ * Otherwise, return 0;
+ *
+ * We first check if the two basic maps live in the same local space.
+ * If so, we do the complete check. Otherwise, we check if one is
+ * an obvious subset of the other.
+ */
+static int coalesce_pair(__isl_keep isl_map *map, int i, int j,
+ struct isl_tab **tabs)
+{
+ int same;
+
+ same = same_divs(map->p[i], map->p[j]);
+ if (same < 0)
+ return -1;
+ if (same)
+ return coalesce_local_pair(map, i, j, tabs);
+
+ return check_coalesce_subset(map, i, j, tabs);
+}
+
static struct isl_map *coalesce(struct isl_map *map, struct isl_tab **tabs)
{
int i, j;
/* For each pair of basic maps in the map, check if the union of the two
* can be represented by a single basic map.
* If so, replace the pair by the single basic map and start over.
+ *
+ * Since we are constructing the tableaus of the basic maps anyway,
+ * we exploit them to detect implicit equalities and redundant constraints.
+ * This also helps the coalescing as it can ignore the redundant constraints.
+ * In order to avoid confusion, we make all implicit equalities explicit
+ * in the basic maps. We don't call isl_basic_map_gauss, though,
+ * as that may affect the number of constraints.
+ * This means that we have to call isl_basic_map_gauss at the end
+ * of the computation to ensure that the basic maps are not left
+ * in an unexpected state.
*/
struct isl_map *isl_map_coalesce(struct isl_map *map)
{
if (map->n <= 1)
return map;
- map = isl_map_align_divs(map);
+ map = isl_map_sort_divs(map);
+ map = isl_map_cow(map);
tabs = isl_calloc_array(map->ctx, struct isl_tab *, map->n);
if (!tabs)
if (!ISL_F_ISSET(map->p[i], ISL_BASIC_MAP_NO_IMPLICIT))
if (isl_tab_detect_implicit_equalities(tabs[i]) < 0)
goto error;
+ map->p[i] = isl_tab_make_equalities_explicit(tabs[i],
+ map->p[i]);
+ if (!map->p[i])
+ goto error;
if (!ISL_F_ISSET(map->p[i], ISL_BASIC_MAP_NO_REDUNDANT))
if (isl_tab_detect_redundant(tabs[i]) < 0)
goto error;
for (i = 0; i < map->n; ++i) {
map->p[i] = isl_basic_map_update_from_tab(map->p[i],
tabs[i]);
+ map->p[i] = isl_basic_map_gauss(map->p[i], NULL);
map->p[i] = isl_basic_map_finalize(map->p[i]);
if (!map->p[i])
goto error;
projects / platform / upstream / isl.git / blobdiff