Index: include/clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h
===================================================================
--- include/clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h
+++ include/clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h
@@ -341,15 +341,27 @@
 
   /// Create a new state in which the statement is marked as tainted.
   ProgramStateRef addTaint(const Stmt *S, const LocationContext *LCtx,
-                               TaintTagType Kind = TaintTagGeneric) const;
+                           TaintTagType Kind = TaintTagGeneric) const;
 
   /// Create a new state in which the symbol is marked as tainted.
   ProgramStateRef addTaint(SymbolRef S,
-                               TaintTagType Kind = TaintTagGeneric) const;
+                           TaintTagType Kind = TaintTagGeneric) const;
 
   /// Create a new state in which the region symbol is marked as tainted.
   ProgramStateRef addTaint(const MemRegion *R,
-                               TaintTagType Kind = TaintTagGeneric) const;
+                           TaintTagType Kind = TaintTagGeneric) const;
+
+  /// Create a new state in which the statement is marked as non-tainted.
+  ProgramStateRef removeTaint(const Stmt *S, const LocationContext *LCtx,
+                              TaintTagType Kind = TaintTagGeneric) const;
+
+  /// Create a new state in which the symbol is marked as non-tainted.
+  ProgramStateRef removeTaint(SymbolRef S,
+                              TaintTagType Kind = TaintTagGeneric) const;
+
+  /// Create a new state in which the region symbol is marked as non-tainted.
+  ProgramStateRef removeTaint(const MemRegion *R,
+                              TaintTagType Kind = TaintTagGeneric) const;
 
   /// Check if the statement is tainted in the current state.
   bool isTainted(const Stmt *S, const LocationContext *LCtx,
Index: lib/StaticAnalyzer/Core/ProgramState.cpp
===================================================================
--- lib/StaticAnalyzer/Core/ProgramState.cpp
+++ lib/StaticAnalyzer/Core/ProgramState.cpp
@@ -648,32 +648,24 @@
   return true;
 }
 
-ProgramStateRef ProgramState::addTaint(const Stmt *S,
-                                           const LocationContext *LCtx,
-                                           TaintTagType Kind) const {
-  if (const Expr *E = dyn_cast_or_null<Expr>(S))
-    S = E->IgnoreParens();
-
+ProgramStateRef ProgramState::addTaint(const Stmt *S, const LocationContext
+                                       *LCtx, TaintTagType Kind) const {
   SymbolRef Sym = getSVal(S, LCtx).getAsSymbol();
   if (Sym)
     return addTaint(Sym, Kind);
 
   const MemRegion *R = getSVal(S, LCtx).getAsRegion();
-  addTaint(R, Kind);
-
-  // Cannot add taint, so just return the state.
-  return this;
+  return addTaint(R, Kind);
 }
 
 ProgramStateRef ProgramState::addTaint(const MemRegion *R,
-                                           TaintTagType Kind) const {
+                                       TaintTagType Kind) const {
   if (const SymbolicRegion *SR = dyn_cast_or_null<SymbolicRegion>(R))
     return addTaint(SR->getSymbol(), Kind);
   return this;
 }
 
-ProgramStateRef ProgramState::addTaint(SymbolRef Sym,
-                                           TaintTagType Kind) const {
+ProgramStateRef ProgramState::addTaint(SymbolRef Sym, TaintTagType Kind) const {
   // If this is a symbol cast, remove the cast before adding the taint. Taint
   // is cast agnostic.
   while (const SymbolCast *SC = dyn_cast<SymbolCast>(Sym))
@@ -684,6 +676,35 @@
   return NewState;
 }
 
+ProgramStateRef ProgramState::removeTaint(const Stmt *S, const LocationContext
+                                          *LCtx, TaintTagType Kind) const {
+  SymbolRef Sym = getSVal(S, LCtx).getAsSymbol();
+  if (Sym)
+    return removeTaint(Sym, Kind);
+
+  const MemRegion *R = getSVal(S, LCtx).getAsRegion();
+  return removeTaint(R, Kind);
+}
+
+ProgramStateRef ProgramState::removeTaint(const MemRegion *R,
+                                          TaintTagType Kind) const {
+  if (const SymbolicRegion *SR = dyn_cast_or_null<SymbolicRegion>(R))
+    return removeTaint(SR->getSymbol(), Kind);
+  return this;
+}
+
+ProgramStateRef ProgramState::removeTaint(SymbolRef Sym,
+                                          TaintTagType Kind) const {
+  // If this is a symbol cast, remove the cast before removing the taint. Taint
+  // is cast agnostic.
+  while (const SymbolCast *SC = dyn_cast<SymbolCast>(Sym))
+    Sym = SC->getOperand();
+
+  ProgramStateRef NewState = remove<TaintMap>(Sym);
+  assert(NewState);
+  return NewState;
+}
+
 bool ProgramState::isTainted(const Stmt *S, const LocationContext *LCtx,
                              TaintTagType Kind) const {
   if (const Expr *E = dyn_cast_or_null<Expr>(S))