From 9ddd482578caee7d8e39d64abfc2500185bff55e Mon Sep 17 00:00:00 2001
From: Sven Verdoolaege <skimo@kotnet.org>
Date: Thu, 25 Sep 2008 10:07:39 +0200
Subject: [PATCH] add isl_set_fast_dim_is_fixed and isl_map_fast_input_is_fixed

---
 include/isl_map.h |  3 +++
 include/isl_set.h |  2 ++
 isl_map.c         | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 85 insertions(+)

diff --git a/include/isl_map.h b/include/isl_map.h
index 1e656d2..43ca895 100644
--- a/include/isl_map.h
+++ b/include/isl_map.h
@@ -209,6 +209,9 @@ int isl_map_is_equal(struct isl_map *map1, struct isl_map *map2);
 
 void isl_map_dump(struct isl_map *map, FILE *out, int indent);
 
+int isl_map_fast_input_is_fixed(struct isl_map *map,
+		unsigned in, isl_int *val);
+
 #if defined(__cplusplus)
 }
 #endif
diff --git a/include/isl_set.h b/include/isl_set.h
index 8d5dfaf..3ceef62 100644
--- a/include/isl_set.h
+++ b/include/isl_set.h
@@ -149,6 +149,8 @@ struct isl_basic_set *isl_set_copy_basic_set(struct isl_set *set);
 struct isl_set *isl_set_drop_basic_set(struct isl_set *set,
 						struct isl_basic_set *bset);
 
+int isl_set_fast_dim_is_fixed(struct isl_set *set, unsigned dim, isl_int *val);
+
 #if defined(__cplusplus)
 }
 #endif
diff --git a/isl_map.c b/isl_map.c
index 7e2c8da..a981d56 100644
--- a/isl_map.c
+++ b/isl_map.c
@@ -3696,3 +3696,83 @@ error:
 	isl_basic_map_free(bmap2);
 	return -2;
 }
+
+static int isl_basic_map_fast_has_fixed_var(struct isl_basic_map *bmap,
+	unsigned pos, isl_int *val)
+{
+	int i;
+	int d;
+	unsigned total;
+
+	if (!bmap)
+		return -1;
+	total = bmap->nparam + bmap->n_in + bmap->n_out + bmap->n_div;
+	for (i = 0, d = total-1; i < bmap->n_eq && d+1 > pos; ++i) {
+		for (; d+1 > pos; --d)
+			if (!isl_int_is_zero(bmap->eq[i][1+d]))
+				break;
+		if (d != pos)
+			continue;
+		if (isl_seq_first_non_zero(bmap->eq[i]+1, d) != -1)
+			return 0;
+		if (isl_seq_first_non_zero(bmap->eq[i]+1+d+1, total-d-1) != -1)
+			return 0;
+		if (!isl_int_is_one(bmap->eq[i][1+d]))
+			return 0;
+		if (val)
+			isl_int_neg(*val, bmap->eq[i][0]);
+		return 1;
+	}
+	return 0;
+}
+
+static int isl_map_fast_has_fixed_var(struct isl_map *map,
+	unsigned pos, isl_int *val)
+{
+	int i;
+	isl_int v;
+	isl_int tmp;
+	int fixed;
+
+	if (!map)
+		return -1;
+	if (map->n == 0)
+		return 0;
+	if (map->n == 1)
+		return isl_basic_map_fast_has_fixed_var(map->p[0], pos, val); 
+	isl_int_init(v);
+	isl_int_init(tmp);
+	fixed = isl_basic_map_fast_has_fixed_var(map->p[0], pos, &v); 
+	for (i = 1; fixed == 1 && i < map->n; ++i) {
+		fixed = isl_basic_map_fast_has_fixed_var(map->p[i], pos, &tmp); 
+		if (fixed == 1 && isl_int_ne(tmp, v))
+			fixed = 0;
+	}
+	if (val)
+		isl_int_set(*val, v);
+	isl_int_clear(tmp);
+	isl_int_clear(v);
+	return fixed;
+}
+
+static int isl_set_fast_has_fixed_var(struct isl_set *set, unsigned pos,
+	isl_int *val)
+{
+	return isl_map_fast_has_fixed_var((struct isl_map *)set, pos, val);
+}
+
+/* Check if dimension dim has fixed value and if so and if val is not NULL,
+ * then return this fixed value in *val.
+ */
+int isl_set_fast_dim_is_fixed(struct isl_set *set, unsigned dim, isl_int *val)
+{
+	return isl_set_fast_has_fixed_var(set, set->nparam + dim, val);
+}
+
+/* Check if input variable in has fixed value and if so and if val is not NULL,
+ * then return this fixed value in *val.
+ */
+int isl_map_fast_input_is_fixed(struct isl_map *map, unsigned in, isl_int *val)
+{
+	return isl_map_fast_has_fixed_var(map, map->nparam + in, val);
+}
-- 
2.7.4