add isl_basic_map_is_single_valued

[platform/upstream/isl.git] / isl_map.c

diff --git a/isl_map.c b/isl_map.c
index 64f27c4..691c88c 100644 (file)
--- a/isl_map.c
+++ b/isl_map.c
@@ -8968,6 +8968,39 @@ int isl_basic_map_plain_is_single_valued(__isl_keep isl_basic_map *bmap)
        return 1;
 }
 
+/* Check if the given basic map is single-valued.
+ * We simply compute
+ *
+ *     M \circ M^-1
+ *
+ * and check if the result is a subset of the identity mapping.
+ */
+int isl_basic_map_is_single_valued(__isl_keep isl_basic_map *bmap)
+{
+       isl_space *space;
+       isl_basic_map *test;
+       isl_basic_map *id;
+       int sv;
+
+       sv = isl_basic_map_plain_is_single_valued(bmap);
+       if (sv < 0 || sv)
+               return sv;
+
+       test = isl_basic_map_reverse(isl_basic_map_copy(bmap));
+       test = isl_basic_map_apply_range(test, isl_basic_map_copy(bmap));
+
+       space = isl_basic_map_get_space(bmap);
+       space = isl_space_map_from_set(isl_space_range(space));
+       id = isl_basic_map_identity(space);
+
+       sv = isl_basic_map_is_subset(test, id);
+
+       isl_basic_map_free(test);
+       isl_basic_map_free(id);
+
+       return sv;
+}
+
 /* Check if the given map is obviously single-valued.
  */
 int isl_map_plain_is_single_valued(__isl_keep isl_map *map)