Implemented segment merging.

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@7750 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/exp-drd/drd_segment.h b/exp-drd/drd_segment.h
index e7eeeeb..487dc22 100644
--- a/exp-drd/drd_segment.h
+++ b/exp-drd/drd_segment.h
@@ -53,6 +53,7 @@
 int sg_get_refcnt(const Segment* const sg);
 Segment* sg_get(Segment* const sg);
 void sg_put(Segment* const sg);
+void sg_merge(const Segment* const sg1, Segment* const sg2);
 void sg_print(const Segment* const sg);
 Bool sg_get_trace(void);
 void sg_set_trace(const Bool trace_segment);