add isl_map_remove_empty_parts

diff --git a/isl_map.c b/isl_map.c
index a0b5105..38308ae 100644 (file)
--- a/isl_map.c
+++ b/isl_map.c
@@ -3040,3 +3040,33 @@ error:
        isl_map_free(ctx, map);
        return NULL;
 }
+
+/* There is no need to cow as removing empty parts doesn't change
+ * the meaning of the set.
+ */
+struct isl_map *isl_map_remove_empty_parts(struct isl_ctx *ctx,
+       struct isl_map *map)
+{
+       int i;
+
+       if (!map)
+               return NULL;
+
+       for (i = map->n-1; i >= 0; --i) {
+               if (!F_ISSET(map->p[i], ISL_BASIC_MAP_EMPTY))
+                       continue;
+               isl_basic_map_free(ctx, map->p[i]);
+               if (i != map->n-1)
+                       map->p[i] = map->p[map->n-1];
+               map->n--;
+       }
+
+       return map;
+}
+
+struct isl_set *isl_set_remove_empty_parts(struct isl_ctx *ctx,
+       struct isl_set *set)
+{
+       return (struct isl_set *)
+               isl_map_remove_empty_parts(ctx, (struct isl_map *)set);
+}

diff --git a/isl_map_private.h b/isl_map_private.h
index f57763f..2a62487 100644 (file)
--- a/isl_map_private.h
+++ b/isl_map_private.h
@@ -42,3 +42,8 @@ struct isl_basic_map *isl_basic_map_gauss(struct isl_ctx *ctx,
        struct isl_basic_map *bmap, int *progress);
 struct isl_basic_set *isl_basic_set_gauss(struct isl_ctx *ctx,
        struct isl_basic_set *bset, int *progress);
+
+struct isl_map *isl_map_remove_empty_parts(struct isl_ctx *ctx,
+       struct isl_map *map);
+struct isl_set *isl_set_remove_empty_parts(struct isl_ctx *ctx,
+       struct isl_set *set);