diff --git a/hpvm/include/BuildDFG/BuildDFG.h b/hpvm/include/BuildDFG/BuildDFG.h
index ca4c616da5f4076528b1294992ec8ad3ab768809..f568ffc7c3083050b6d5c40d7c2779951aad73d9 100644
--- a/hpvm/include/BuildDFG/BuildDFG.h
+++ b/hpvm/include/BuildDFG/BuildDFG.h
@@ -9,6 +9,12 @@
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
+//
+// This pass defines the BuildDFG pass which uses LLVM IR with HPVM intrinsics
+// to infer information about dataflow graph hierarchy and structure to construct
+// HPVM IR. 
+//
+//===----------------------------------------------------------------------===//
 
 #include "SupportHPVM/DFGraph.h"
 #include "llvm/IR/Function.h"