From 2a431f80d4956a4430dd49e75a4f4cd45509f347 Mon Sep 17 00:00:00 2001
From: Sven Verdoolaege <skimo@kotnet.org>
Date: Sat, 10 Oct 2009 15:09:10 +0200
Subject: [PATCH] isl_map_is_subset: exploit another easy special case

---
 isl_map.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/isl_map.c b/isl_map.c
index 57b9ad9..796af48 100644
--- a/isl_map.c
+++ b/isl_map.c
@@ -4079,6 +4079,9 @@ int isl_map_is_subset(struct isl_map *map1, struct isl_map *map2)
 	if (isl_map_is_empty(map2))
 		return 0;
 
+	if (isl_map_fast_is_universe(map2))
+		return 1;
+
 	diff = isl_map_subtract(isl_map_copy(map1), isl_map_copy(map2));
 	if (!diff)
 		return -1;
-- 
2.7.4