+/* Given a basic map with a single output dimension that is defined
+ * in terms of the parameters and input dimensions using an equality,
+ * extract an isl_aff that expresses the output dimension in terms
+ * of the parameters and input dimensions.
+ *
+ * Since some applications expect the result of isl_pw_multi_aff_from_map
+ * to only contain integer affine expressions, we compute the floor
+ * of the expression before returning.
+ *
+ * This function shares some similarities with
+ * isl_basic_map_has_defining_equality and isl_constraint_get_bound.
+ */
+static __isl_give isl_aff *extract_isl_aff_from_basic_map(
+ __isl_take isl_basic_map *bmap)
+{
+ int i;
+ unsigned offset;
+ unsigned total;
+ isl_local_space *ls;
+ isl_aff *aff;
+
+ if (!bmap)
+ return NULL;
+ if (isl_basic_map_dim(bmap, isl_dim_out) != 1)
+ isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
+ "basic map should have a single output dimension",
+ goto error);
+ offset = isl_basic_map_offset(bmap, isl_dim_out);
+ total = isl_basic_map_total_dim(bmap);
+ for (i = 0; i < bmap->n_eq; ++i) {
+ if (isl_int_is_zero(bmap->eq[i][offset]))
+ continue;
+ if (isl_seq_first_non_zero(bmap->eq[i] + offset + 1,
+ 1 + total - (offset + 1)) != -1)
+ continue;
+ break;
+ }
+ if (i >= bmap->n_eq)
+ isl_die(isl_basic_map_get_ctx(bmap), isl_error_invalid,
+ "unable to find suitable equality", goto error);
+ ls = isl_basic_map_get_local_space(bmap);
+ aff = isl_aff_alloc(isl_local_space_domain(ls));
+ if (!aff)
+ goto error;
+ if (isl_int_is_neg(bmap->eq[i][offset]))
+ isl_seq_cpy(aff->v->el + 1, bmap->eq[i], offset);
+ else
+ isl_seq_neg(aff->v->el + 1, bmap->eq[i], offset);
+ isl_seq_clr(aff->v->el + 1 + offset, aff->v->size - (1 + offset));
+ isl_int_abs(aff->v->el[0], bmap->eq[i][offset]);
+ isl_basic_map_free(bmap);
+
+ aff = isl_aff_remove_unused_divs(aff);
+ aff = isl_aff_floor(aff);
+ return aff;
+error:
+ isl_basic_map_free(bmap);
+ return NULL;
+}
+
+/* Given a basic map where each output dimension is defined
+ * in terms of the parameters and input dimensions using an equality,
+ * extract an isl_multi_aff that expresses the output dimensions in terms
+ * of the parameters and input dimensions.
+ */
+static __isl_give isl_multi_aff *extract_isl_multi_aff_from_basic_map(
+ __isl_take isl_basic_map *bmap)
+{
+ int i;
+ unsigned n_out;
+ isl_multi_aff *ma;
+
+ if (!bmap)
+ return NULL;
+
+ ma = isl_multi_aff_alloc(isl_basic_map_get_space(bmap));
+ n_out = isl_basic_map_dim(bmap, isl_dim_out);
+
+ for (i = 0; i < n_out; ++i) {
+ isl_basic_map *bmap_i;
+ isl_aff *aff;
+
+ bmap_i = isl_basic_map_copy(bmap);
+ bmap_i = isl_basic_map_project_out(bmap_i, isl_dim_out,
+ i + 1, n_out - (1 + i));
+ bmap_i = isl_basic_map_project_out(bmap_i, isl_dim_out, 0, i);
+ aff = extract_isl_aff_from_basic_map(bmap_i);
+ ma = isl_multi_aff_set_aff(ma, i, aff);
+ }
+
+ isl_basic_map_free(bmap);
+
+ return ma;
+}
+
+/* Create an isl_pw_multi_aff that is equivalent to
+ * isl_map_intersect_domain(isl_map_from_basic_map(bmap), domain).
+ * The given basic map is such that each output dimension is defined
+ * in terms of the parameters and input dimensions using an equality.
+ */
+static __isl_give isl_pw_multi_aff *plain_pw_multi_aff_from_map(
+ __isl_take isl_set *domain, __isl_take isl_basic_map *bmap)
+{
+ isl_multi_aff *ma;
+
+ ma = extract_isl_multi_aff_from_basic_map(bmap);
+ return isl_pw_multi_aff_alloc(domain, ma);
+}
+