Fixed bogus culling of uninitialized-values "taint" propagation during assignments.
We accidentally were throttling the propagation of uninitialized state across
assignments (e.g. x = y).  Thanks to Anders Carlsson for spotting this problem.

Added test cases to test suite to provide regression testing for the
uninitialized values analysis.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@44306 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Analysis/UninitializedValues.cpp b/Analysis/UninitializedValues.cpp
index 0a49659..8a27b71 100644
--- a/Analysis/UninitializedValues.cpp
+++ b/Analysis/UninitializedValues.cpp
@@ -101,6 +101,8 @@
     else if (DeclRefExpr* DR = dyn_cast<DeclRefExpr>(S)) {
       if (BlockVarDecl* VD = dyn_cast<BlockVarDecl>(DR->getDecl()))
         return VD;
+      else
+        return NULL;
     }
     else return NULL;
 }
@@ -108,16 +110,10 @@
 bool TransferFuncs::VisitBinaryOperator(BinaryOperator* B) {
   if (BlockVarDecl* VD = FindBlockVarDecl(B->getLHS()))
     if (B->isAssignmentOp()) {
-      if (AD.FullUninitTaint) {
-        if (B->getOpcode() == BinaryOperator::Assign)
-          return V(VD,AD) = Visit(B->getRHS());
-        else // Handle +=, -=, *=, etc.  We do want '&', not '&&'.
-          return V(VD,AD) = Visit(B->getLHS()) & Visit(B->getRHS());
-      }
-      else {
-        Visit(B->getLHS()); Visit(B->getRHS());
-        return Initialized;
-      }
+      if (B->getOpcode() == BinaryOperator::Assign)
+        return V(VD,AD) = Visit(B->getRHS());
+      else // Handle +=, -=, *=, etc.  We do want '&', not '&&'.
+        return V(VD,AD) = Visit(B->getLHS()) & Visit(B->getRHS());
     }
 
   return VisitStmt(B);