If the first argument of isl_union_map_is_subset contains an empty
set in some space that is not present in the second argument,
then isl_union_map_is_subset would incorrectly draw the conclusion
that the first is not a subset of the second.
Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>
entry2 = isl_hash_table_find(data->umap2->dim->ctx, &data->umap2->table,
hash, &has_dim, map->dim, 0);
if (!entry2) {
+ int empty = isl_map_is_empty(map);
+ if (empty < 0)
+ return -1;
+ if (empty)
+ return 0;
data->is_subset = 0;
return -1;
}