add isl_set_lifting

diff --git a/include/isl_map.h b/include/isl_map.h
index 887393c..636e593 100644 (file)
--- a/include/isl_map.h
+++ b/include/isl_map.h
@@ -307,6 +307,8 @@ int isl_map_fast_is_equal(__isl_keep isl_map *map1, __isl_keep isl_map *map2);
 int isl_map_foreach_basic_map(__isl_keep isl_map *map,
        int (*fn)(__isl_take isl_basic_map *bmap, void *user), void *user);
 
+__isl_give isl_map *isl_set_lifting(__isl_take isl_set *set);
+
 #if defined(__cplusplus)
 }
 #endif

diff --git a/isl_map.c b/isl_map.c
index 5d7a01c..2de215e 100644 (file)
--- a/isl_map.c
+++ b/isl_map.c
@@ -4271,6 +4271,10 @@ struct isl_map *isl_map_align_divs(struct isl_map *map)
 {
        int i;
 
+       if (!map)
+               return NULL;
+       if (map->n == 0)
+               return map;
        map = isl_map_compute_divs(map);
        map = isl_map_cow(map);
        if (!map)
@@ -5310,3 +5314,62 @@ int isl_map_foreach_basic_map(__isl_keep isl_map *map,
 
        return 0;
 }
+
+__isl_give isl_map *isl_set_lifting(__isl_take isl_set *set)
+{
+       struct isl_dim *dim;
+       struct isl_basic_map *bmap;
+       unsigned n_set;
+       unsigned n_div;
+       unsigned n_param;
+       unsigned total;
+       int i, k, l;
+
+       set = isl_set_align_divs(set);
+
+       if (!set)
+               return NULL;
+
+       dim = isl_set_get_dim(set);
+       if (set->n == 0 || set->p[0]->n_div == 0) {
+               isl_set_free(set);
+               return isl_map_identity(dim);
+       }
+
+       n_div = set->p[0]->n_div;
+       dim = isl_dim_map(dim);
+       n_param = isl_dim_size(dim, isl_dim_param);
+       n_set = isl_dim_size(dim, isl_dim_in);
+       dim = isl_dim_extend(dim, n_param, n_set, n_set + n_div);
+       bmap = isl_basic_map_alloc_dim(dim, 0, n_set, 2 * n_div);
+       for (i = 0; i < n_set; ++i)
+               bmap = var_equal(bmap, i);
+
+       total = n_param + n_set + n_set + n_div;
+       for (i = 0; i < n_div; ++i) {
+               k = isl_basic_map_alloc_inequality(bmap);
+               if (k < 0)
+                       goto error;
+               isl_seq_cpy(bmap->ineq[k], set->p[0]->div[i]+1, 1+n_param);
+               isl_seq_clr(bmap->ineq[k]+1+n_param, n_set);
+               isl_seq_cpy(bmap->ineq[k]+1+n_param+n_set,
+                           set->p[0]->div[i]+1+1+n_param, n_set + n_div);
+               isl_int_neg(bmap->ineq[k][1+n_param+n_set+n_set+i],
+                           set->p[0]->div[i][0]);
+
+               l = isl_basic_map_alloc_inequality(bmap);
+               if (l < 0)
+                       goto error;
+               isl_seq_neg(bmap->ineq[l], bmap->ineq[k], 1 + total);
+               isl_int_add(bmap->ineq[l][0], bmap->ineq[l][0],
+                           set->p[0]->div[i][0]);
+               isl_int_sub_ui(bmap->ineq[l][0], bmap->ineq[l][0], 1);
+       }
+
+       isl_set_free(set);
+       return isl_map_from_basic_map(bmap);
+error:
+       isl_set_free(set);
+       isl_basic_map_free(bmap);
+       return NULL;
+}