Add SparseBitVector implementation


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41790 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CREDITS.TXT b/CREDITS.TXT
index bdd20fb..e1e1af3 100644
--- a/CREDITS.TXT
+++ b/CREDITS.TXT
@@ -29,6 +29,7 @@
 N: Daniel Berlin
 E: dberlin@dberlin.org
 D: ET-Forest implementation.
+D: Sparse bitmap
 
 N: Neil Booth
 E: neil@daikokuya.co.uk