From: Sven Verdoolaege <skimo@kotnet.org>
Date: Sat, 9 Aug 2008 12:14:12 +0000 (+0200)
Subject: isl_basic_map_is_empty: special case known empty basic sets
X-Git-Tag: isl-0.01~459
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=92be44b2a7d8c292c746fb9a06da79c71c85b4c4;p=platform%2Fupstream%2Fisl.git

isl_basic_map_is_empty: special case known empty basic sets
---

diff --git a/include/isl_map.h b/include/isl_map.h
index 0ce4df2..8af220c 100644
--- a/include/isl_map.h
+++ b/include/isl_map.h
@@ -36,6 +36,7 @@ extern "C" {
 struct isl_basic_map {
 	int ref;
 #define ISL_BASIC_MAP_FINAL		(1 << 0)
+#define ISL_BASIC_MAP_EMPTY		(1 << 1)
 	unsigned flags;
 
 	unsigned nparam;
diff --git a/include/isl_set.h b/include/isl_set.h
index 2bdc27a..b45a301 100644
--- a/include/isl_set.h
+++ b/include/isl_set.h
@@ -13,6 +13,7 @@ extern "C" {
 struct isl_basic_set {
 	int ref;
 #define ISL_BASIC_SET_FINAL		(1 << 0)
+#define ISL_BASIC_SET_EMPTY		(1 << 1)
 	unsigned flags;
 
 	unsigned nparam;
diff --git a/isl_map.c b/isl_map.c
index 97621bd..99045af 100644
--- a/isl_map.c
+++ b/isl_map.c
@@ -662,6 +662,7 @@ struct isl_basic_map *isl_basic_map_set_to_empty(
 	}
 	isl_int_set_si(bmap->eq[i][0], 1);
 	isl_seq_clr(bmap->eq[i]+1, total);
+	F_SET(bmap, ISL_BASIC_MAP_EMPTY);
 	return isl_basic_map_finalize(ctx, bmap);
 error:
 	isl_basic_map_free(ctx, bmap);
@@ -2484,6 +2485,9 @@ int isl_basic_map_is_empty(struct isl_ctx *ctx,
 	if (!bmap)
 		return -1;
 
+	if (F_ISSET(bmap, ISL_BASIC_MAP_EMPTY))
+		return 1;
+
 	bset = isl_basic_set_from_basic_map(ctx,
 			isl_basic_map_copy(ctx, bmap));
 	if (!bset)