Add comments to test case.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@97619 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Analysis/inline2.c b/test/Analysis/inline2.c
index 9029fb9..e2758c1 100644
--- a/test/Analysis/inline2.c
+++ b/test/Analysis/inline2.c
@@ -2,6 +2,8 @@
 
 // Test parameter 'a' is registered to LiveVariables analysis data although it
 // is not referenced in the function body. 
+// Before processing 'return 1;', in RemoveDeadBindings(), we query the liveness
+// of 'a', because we have a binding for it due to parameter passing.
 int f1(int a) {
   return 1;
 }