Make generic algorithm a little less generic.

src/compiler/generic-algorithm.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_GENERIC_ALGORITHM_H_
 #define V8_COMPILER_GENERIC_ALGORITHM_H_
 
 #include <stack>
+#include <vector>
 
+#include "src/compiler/graph.h"
+#include "src/compiler/node.h"
 #include "src/zone-containers.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 class Graph;
 class Node;
 
 // GenericGraphVisit allows visitation of graphs of nodes and edges in pre- and
 // post-order. Visitation uses an explicitly allocated stack rather than the
-// execution stack to avoid stack overflow. Although GenericGraphVisit is
-// primarily intended to traverse networks of nodes through their
-// dependencies and uses, it also can be used to visit any graph-like network
-// by specifying custom traits.
+// execution stack to avoid stack overflow.
 class GenericGraphVisit {
  public:
   // struct Visitor {
-  //   void Pre(Traits::Node* current);
-  //   void Post(Traits::Node* current);
-  //   void PreEdge(Traits::Node* from, int index, Traits::Node* to);
-  //   void PostEdge(Traits::Node* from, int index, Traits::Node* to);
+  //   void Pre(Node* current);
+  //   void Post(Node* current);
+  //   void PreEdge(Node* from, int index, Node* to);
+  //   void PostEdge(Node* from, int index, Node* to);
   // }
-  template <class Visitor, class Traits, class RootIterator>
-  static void Visit(Graph* graph, Zone* zone, RootIterator root_begin,
-                    RootIterator root_end, Visitor* visitor) {
-    typedef typename Traits::Node Node;
-    typedef typename Traits::Iterator Iterator;
+  template <class Visitor>
+  static void Visit(Graph* graph, Zone* zone, Node** root_begin,
+                    Node** root_end, Visitor* visitor) {
+    typedef typename Node::InputEdges::iterator Iterator;
     typedef std::pair<Iterator, Iterator> NodeState;
     typedef std::stack<NodeState, ZoneDeque<NodeState> > NodeStateStack;
     NodeStateStack stack((ZoneDeque<NodeState>(zone)));
-    BoolVector visited(Traits::max_id(graph), false, zone);
+    BoolVector visited(graph->NodeCount(), false, zone);
     Node* current = *root_begin;
     while (true) {
       DCHECK(current != NULL);
       const int id = current->id();
       DCHECK(id >= 0);
-      DCHECK(id < Traits::max_id(graph));  // Must be a valid id.
+      DCHECK(id < graph->NodeCount());  // Must be a valid id.
       bool visit = !GetVisited(&visited, id);
       if (visit) {
         visitor->Pre(current);
         SetVisited(&visited, id);
       }
-      Iterator begin(visit ? Traits::begin(current) : Traits::end(current));
-      Iterator end(Traits::end(current));
+      Iterator begin(visit ? current->input_edges().begin()
+                           : current->input_edges().end());
+      Iterator end(current->input_edges().end());
       stack.push(NodeState(begin, end));
       Node* post_order_node = current;
       while (true) {
         NodeState top = stack.top();
         if (top.first == top.second) {
           if (visit) {
             visitor->Post(post_order_node);
             SetVisited(&visited, post_order_node->id());
           }
           stack.pop();
           if (stack.empty()) {
             if (++root_begin == root_end) return;
             current = *root_begin;
             break;
           }
-          post_order_node = Traits::from(stack.top().first);
+          post_order_node = (*stack.top().first).from();
           visit = true;
         } else {
-          visitor->PreEdge(Traits::from(top.first), (*top.first).index(),
-                           Traits::to(top.first));
-          current = Traits::to(top.first);
+          visitor->PreEdge((*top.first).from(), (*top.first).index(),
+                           (*top.first).to());
+          current = (*top.first).to();
           if (!GetVisited(&visited, current->id())) break;
         }
         top = stack.top();
-        visitor->PostEdge(Traits::from(top.first), (*top.first).index(),
-                          Traits::to(top.first));
+        visitor->PostEdge((*top.first).from(), (*top.first).index(),
+                          (*top.first).to());
         ++stack.top().first;
       }
     }
   }
 
-  template <class Visitor, class Traits>
-  static void Visit(Graph* graph, Zone* zone, typename Traits::Node* current,
-                    Visitor* visitor) {
-    typename Traits::Node* array[] = {current};
-    Visit<Visitor, Traits>(graph, zone, &array[0], &array[1], visitor);
+  template <class Visitor>
+  static void Visit(Graph* graph, Zone* zone, Node* current, Visitor* visitor) {
+    Node* array[] = {current};
+    Visit<Visitor>(graph, zone, &array[0], &array[1], visitor);
   }
 
   struct NullNodeVisitor {
     void Pre(Node* node) {}
     void Post(Node* node) {}
     void PreEdge(Node* from, int index, Node* to) {}
     void PostEdge(Node* from, int index, Node* to) {}
   };
 
  private:
   static void SetVisited(BoolVector* visited, int id) {
     if (id >= static_cast<int>(visited->size())) {
       // Resize and set all values to unvisited.
       visited->resize((3 * id) / 2, false);
     }
     visited->at(id) = true;
   }
 
   static bool GetVisited(BoolVector* visited, int id) {
     if (id >= static_cast<int>(visited->size())) return false;
     return visited->at(id);
   }
 };
-}
-}
-}  // namespace v8::internal::compiler
+
+typedef GenericGraphVisit::NullNodeVisitor NullNodeVisitor;
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_COMPILER_GENERIC_ALGORITHM_H_