From 6e524e26c4b66f743d78bbc0070f654b36d966cd Mon Sep 17 00:00:00 2001
From: Sven Verdoolaege <skimo@kotnet.org>
Date: Thu, 8 Sep 2011 22:08:03 +0200
Subject: [PATCH] add isl_local_space_lifting

Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>
---
 doc/user.pod              |  9 +++++++++
 include/isl/local_space.h |  4 ++++
 isl_local_space.c         | 24 ++++++++++++++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/doc/user.pod b/doc/user.pod
index 74a1e69..59d086d 100644
--- a/doc/user.pod
+++ b/doc/user.pod
@@ -2088,6 +2088,15 @@ existentially quantified variables.
 	__isl_give isl_union_set *isl_union_set_lift(
 		__isl_take isl_union_set *uset);
 
+Given a local space that contains the existentially quantified
+variables of a set, a basic relation that, when applied to
+a basic set, has essentially the same effect as C<isl_basic_set_lift>,
+can be constructed using the following function.
+
+	#include <isl/local_space.h>
+	__isl_give isl_basic_map *isl_local_space_lifting(
+		__isl_take isl_local_space *ls);
+
 =item * Internal Product
 
 	__isl_give isl_basic_map *isl_basic_map_zip(
diff --git a/include/isl/local_space.h b/include/isl/local_space.h
index be116c6..7f73e0b 100644
--- a/include/isl/local_space.h
+++ b/include/isl/local_space.h
@@ -4,6 +4,7 @@
 #include <isl/aff_type.h>
 #include <isl/space.h>
 #include <isl/printer.h>
+#include <isl/map_type.h>
 
 #if defined(__cplusplus)
 extern "C" {
@@ -55,6 +56,9 @@ __isl_give isl_local_space *isl_local_space_intersect(
 int isl_local_space_is_equal(__isl_keep isl_local_space *ls1,
 	__isl_keep isl_local_space *ls2);
 
+__isl_give isl_basic_map *isl_local_space_lifting(
+	__isl_take isl_local_space *ls);
+
 __isl_give isl_printer *isl_printer_print_local_space(__isl_take isl_printer *p,
 	__isl_keep isl_local_space *ls);
 void isl_local_space_dump(__isl_keep isl_local_space *ls);
diff --git a/isl_local_space.c b/isl_local_space.c
index 0bbd0e0..8a27e81 100644
--- a/isl_local_space.c
+++ b/isl_local_space.c
@@ -856,3 +856,27 @@ __isl_give isl_local_space *isl_local_space_lift(
 
 	return ls;
 }
+
+/* Construct a basic map that maps a set living in local space "ls"
+ * to the corresponding lifted local space.
+ */
+__isl_give isl_basic_map *isl_local_space_lifting(
+	__isl_take isl_local_space *ls)
+{
+	isl_basic_map *lifting;
+	isl_basic_set *bset;
+
+	if (!ls)
+		return NULL;
+	if (!isl_local_space_is_set(ls))
+		isl_die(isl_local_space_get_ctx(ls), isl_error_invalid,
+			"lifting only defined on set spaces",
+			return isl_local_space_free(ls));
+
+	bset = isl_basic_set_from_local_space(ls);
+	lifting = isl_basic_set_unwrap(isl_basic_set_lift(bset));
+	lifting = isl_basic_map_domain_map(lifting);
+	lifting = isl_basic_map_reverse(lifting);
+
+	return lifting;
+}
-- 
2.7.4