Added main skeleton for CFRetain transfer function logic.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@48214 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Analysis/ValueState.cpp b/Analysis/ValueState.cpp
index 4b097ee..1d428f1 100644
--- a/Analysis/ValueState.cpp
+++ b/Analysis/ValueState.cpp
@@ -442,6 +442,14 @@
   return getPersistentState(NewSt);
 }
 
+void ValueStateManager::Unbind(ValueState& StImpl, LVal LV) {
+  
+  if (isa<lval::DeclVal>(LV))
+    StImpl.VarBindings = VBFactory.Remove(StImpl.VarBindings,
+                                          cast<lval::DeclVal>(LV).getDecl());
+  
+}
+
 ValueState* ValueStateManager::getInitialState() {
 
   // Create a state with empty variable bindings.