[turbofan] Initial import of SimplifiedOperatorReducer.

src/compiler/graph-reducer.h

Index: src/compiler/graph-reducer.h
diff --git a/src/compiler/graph-reducer.h b/src/compiler/graph-reducer.h
index 33cded65a7b5b2fc68bf2d6a833f959003830f4f..b3534e8435ba58570900471e341a4acda24350d3 100644
--- a/src/compiler/graph-reducer.h
+++ b/src/compiler/graph-reducer.h
@@ -38,6 +38,7 @@ class Reduction V8_FINAL {
 // phase.
 class Reducer {
  public:
+  Reducer() {}
   virtual ~Reducer() {}
 
   // Try to reduce a node if possible.
@@ -47,6 +48,9 @@ class Reducer {
   static Reduction NoChange() { return Reduction(); }
   static Reduction Replace(Node* node) { return Reduction(node); }
   static Reduction Changed(Node* node) { return Reduction(node); }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(Reducer);
 };
 
 
@@ -69,9 +73,12 @@ class GraphReducer V8_FINAL {
 
   Graph* graph_;
   Reducers reducers_;
+
+  DISALLOW_COPY_AND_ASSIGN(GraphReducer);
 };
-}
-}
-}  // namespace v8::internal::compiler
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_COMPILER_GRAPH_REDUCER_H_