X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=isl_convex_hull.c;h=dc8ac917a517b4396107f48526965ea278f649f8;hb=de51a9bc4da5dd3f1f9f57c2362da6f9752c44e0;hp=a6e26b8448f0ec47d7c2883aabd177894d3d24c2;hpb=a3e3c35fe631d3dbaa923d3199fc49f615269df7;p=platform%2Fupstream%2Fisl.git

diff --git a/isl_convex_hull.c b/isl_convex_hull.c
index a6e26b8..dc8ac91 100644
--- a/isl_convex_hull.c
+++ b/isl_convex_hull.c
@@ -1,7 +1,7 @@
 /*
  * Copyright 2008-2009 Katholieke Universiteit Leuven
  *
- * 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
@@ -94,7 +94,7 @@ __isl_give isl_basic_map *isl_basic_map_remove_redundancies(
 	if (bmap->n_ineq <= 1)
 		return bmap;
 
-	tab = isl_tab_from_basic_map(bmap);
+	tab = isl_tab_from_basic_map(bmap, 0);
 	if (isl_tab_detect_implicit_equalities(tab) < 0)
 		goto error;
 	if (isl_tab_detect_redundant(tab) < 0)
@@ -483,7 +483,7 @@ static __isl_give isl_mat *initial_facet_constraint(__isl_keep isl_set *set)
 	int i;
 	unsigned dim = isl_set_n_dim(set);
 	int is_bound;
-	isl_mat *bounds;
+	isl_mat *bounds = NULL;
 
 	isl_assert(set->ctx, set->n > 0, goto error);
 	bounds = isl_mat_alloc(set->ctx, 1, 1 + dim);
@@ -1169,7 +1169,7 @@ static struct isl_vec *valid_direction(
 		goto error;
 	lp = valid_direction_lp(isl_basic_set_copy(bset1),
 				isl_basic_set_copy(bset2));
-	tab = isl_tab_from_basic_set(lp);
+	tab = isl_tab_from_basic_set(lp, 0);
 	sample = isl_tab_get_sample_value(tab);
 	isl_tab_free(tab);
 	isl_basic_set_free(lp);
@@ -1867,6 +1867,7 @@ static struct isl_basic_set *uset_convex_hull_wrap_bounded(struct isl_set *set)
 	if (set->n == 1) {
 		convex_hull = isl_basic_set_copy(set->p[0]);
 		isl_set_free(set);
+		convex_hull = isl_basic_map_remove_redundancies(convex_hull);
 		return convex_hull;
 	}
 	if (isl_set_n_dim(set) == 1)
@@ -2106,18 +2107,20 @@ error:
  * it can be relaxed (by increasing the constant term) to become
  * a bound for that basic set.  In the latter case, the constant
  * term is updated.
+ * Relaxation of the constant term is only allowed if "shift" is set.
+ *
  * Return 1 if "ineq" is a bound
  *	  0 if "ineq" may attain arbitrarily small values on basic set "j"
  *	 -1 if some error occurred
  */
 static int is_bound(struct sh_data *data, struct isl_set *set, int j,
-			isl_int *ineq)
+	isl_int *ineq, int shift)
 {
 	enum isl_lp_result res;
 	isl_int opt;
 
 	if (!data->p[j].tab) {
-		data->p[j].tab = isl_tab_from_basic_set(set->p[j]);
+		data->p[j].tab = isl_tab_from_basic_set(set->p[j], 0);
 		if (!data->p[j].tab)
 			return -1;
 	}
@@ -2126,8 +2129,12 @@ static int is_bound(struct sh_data *data, struct isl_set *set, int j,
 
 	res = isl_tab_min(data->p[j].tab, ineq, data->ctx->one,
 				&opt, NULL, 0);
-	if (res == isl_lp_ok && isl_int_is_neg(opt))
-		isl_int_sub(ineq[0], ineq[0], opt);
+	if (res == isl_lp_ok && isl_int_is_neg(opt)) {
+		if (shift)
+			isl_int_sub(ineq[0], ineq[0], opt);
+		else
+			res = isl_lp_unbounded;
+	}
 
 	isl_int_clear(opt);
 
@@ -2135,9 +2142,9 @@ static int is_bound(struct sh_data *data, struct isl_set *set, int j,
 	       res == isl_lp_unbounded ? 0 : -1;
 }
 
-/* Check if inequality "ineq" from basic set "i" can be relaxed to
+/* Check if inequality "ineq" from basic set "i" is or can be relaxed to
  * become a bound on the whole set.  If so, add the (relaxed) inequality
- * to "hull".
+ * to "hull".  Relaxation is only allowed if "shift" is set.
  *
  * We first check if "hull" already contains a translate of the inequality.
  * If so, we are done.
@@ -2153,7 +2160,8 @@ static int is_bound(struct sh_data *data, struct isl_set *set, int j,
  * the inequality accordingly.
  */
 static struct isl_basic_set *add_bound(struct isl_basic_set *hull,
-	struct sh_data *data, struct isl_set *set, int i, isl_int *ineq)
+	struct sh_data *data, struct isl_set *set, int i, isl_int *ineq,
+	int shift)
 {
 	uint32_t c_hash;
 	struct ineq_cmp_data v;
@@ -2188,7 +2196,7 @@ static struct isl_basic_set *add_bound(struct isl_basic_set *hull,
 
 	for (j = 0; j < i; ++j) {
 		int bound;
-		bound = is_bound(data, set, j, hull->ineq[k]);
+		bound = is_bound(data, set, j, hull->ineq[k], shift);
 		if (bound < 0)
 			goto error;
 		if (!bound)
@@ -2216,7 +2224,7 @@ static struct isl_basic_set *add_bound(struct isl_basic_set *hull,
 				isl_int_neg(ineq_j[0], ineq_j[0]);
 			continue;
 		}
-		bound = is_bound(data, set, j, hull->ineq[k]);
+		bound = is_bound(data, set, j, hull->ineq[k], shift);
 		if (bound < 0)
 			goto error;
 		if (!bound)
@@ -2239,12 +2247,12 @@ error:
 	return NULL;
 }
 
-/* Check if any inequality from basic set "i" can be relaxed to
+/* Check if any inequality from basic set "i" is or can be relaxed to
  * become a bound on the whole set.  If so, add the (relaxed) inequality
- * to "hull".
+ * to "hull".  Relaxation is only allowed if "shift" is set.
  */
 static struct isl_basic_set *add_bounds(struct isl_basic_set *bset,
-	struct sh_data *data, struct isl_set *set, int i)
+	struct sh_data *data, struct isl_set *set, int i, int shift)
 {
 	int j, k;
 	unsigned dim = isl_basic_set_total_dim(bset);
@@ -2252,18 +2260,21 @@ static struct isl_basic_set *add_bounds(struct isl_basic_set *bset,
 	for (j = 0; j < set->p[i]->n_eq; ++j) {
 		for (k = 0; k < 2; ++k) {
 			isl_seq_neg(set->p[i]->eq[j], set->p[i]->eq[j], 1+dim);
-			bset = add_bound(bset, data, set, i, set->p[i]->eq[j]);
+			bset = add_bound(bset, data, set, i, set->p[i]->eq[j],
+					    shift);
 		}
 	}
 	for (j = 0; j < set->p[i]->n_ineq; ++j)
-		bset = add_bound(bset, data, set, i, set->p[i]->ineq[j]);
+		bset = add_bound(bset, data, set, i, set->p[i]->ineq[j], shift);
 	return bset;
 }
 
 /* Compute a superset of the convex hull of set that is described
- * by only translates of the constraints in the constituents of set.
+ * by only (translates of) the constraints in the constituents of set.
+ * Translation is only allowed if "shift" is set.
  */
-static struct isl_basic_set *uset_simple_hull(struct isl_set *set)
+static __isl_give isl_basic_set *uset_simple_hull(__isl_take isl_set *set,
+	int shift)
 {
 	struct sh_data *data = NULL;
 	struct isl_basic_set *hull = NULL;
@@ -2289,7 +2300,7 @@ static struct isl_basic_set *uset_simple_hull(struct isl_set *set)
 		goto error;
 
 	for (i = 0; i < set->n; ++i)
-		hull = add_bounds(hull, data, set, i);
+		hull = add_bounds(hull, data, set, i, shift);
 
 	sh_data_free(data);
 	isl_set_free(set);
@@ -2303,9 +2314,11 @@ error:
 }
 
 /* Compute a superset of the convex hull of map that is described
- * by only translates of the constraints in the constituents of map.
+ * by only (translates of) the constraints in the constituents of map.
+ * Translation is only allowed if "shift" is set.
  */
-struct isl_basic_map *isl_map_simple_hull(struct isl_map *map)
+static __isl_give isl_basic_map *map_simple_hull(__isl_take isl_map *map,
+	int shift)
 {
 	struct isl_set *set = NULL;
 	struct isl_basic_map *model = NULL;
@@ -2329,28 +2342,54 @@ struct isl_basic_map *isl_map_simple_hull(struct isl_map *map)
 	map = isl_map_detect_equalities(map);
 	affine_hull = isl_map_affine_hull(isl_map_copy(map));
 	map = isl_map_align_divs(map);
-	model = isl_basic_map_copy(map->p[0]);
+	model = map ? isl_basic_map_copy(map->p[0]) : NULL;
 
 	set = isl_map_underlying_set(map);
 
-	bset = uset_simple_hull(set);
+	bset = uset_simple_hull(set, shift);
 
 	hull = isl_basic_map_overlying_set(bset, model);
 
 	hull = isl_basic_map_intersect(hull, affine_hull);
 	hull = isl_basic_map_remove_redundancies(hull);
+
+	if (!hull)
+		return NULL;
 	ISL_F_SET(hull, ISL_BASIC_MAP_NO_IMPLICIT);
 	ISL_F_SET(hull, ISL_BASIC_MAP_ALL_EQUALITIES);
 
 	return hull;
 }
 
+/* Compute a superset of the convex hull of map that is described
+ * by only translates of the constraints in the constituents of map.
+ */
+__isl_give isl_basic_map *isl_map_simple_hull(__isl_take isl_map *map)
+{
+	return map_simple_hull(map, 1);
+}
+
 struct isl_basic_set *isl_set_simple_hull(struct isl_set *set)
 {
 	return (struct isl_basic_set *)
 		isl_map_simple_hull((struct isl_map *)set);
 }
 
+/* Compute a superset of the convex hull of map that is described
+ * by only the constraints in the constituents of map.
+ */
+__isl_give isl_basic_map *isl_map_unshifted_simple_hull(
+	__isl_take isl_map *map)
+{
+	return map_simple_hull(map, 0);
+}
+
+__isl_give isl_basic_set *isl_set_unshifted_simple_hull(
+	__isl_take isl_set *set)
+{
+	return isl_map_unshifted_simple_hull(set);
+}
+
 /* Given a set "set", return parametric bounds on the dimension "dim".
  */
 static struct isl_basic_set *set_bounds(struct isl_set *set, int dim)