[turbofan] Support for combining branches with <Operation>WithOverflow.

src/compiler/node.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_NODE_H_
 #define V8_COMPILER_NODE_H_
 
 #include <deque>
 #include <set>
 #include <vector>
@@ skipping 37 matching lines @@
 // needs to be associated with Nodes during compilation must be stored
 // out-of-line indexed by the Node's id.
 class Node : public GenericNode<NodeData, Node> {
  public:
   Node(GenericGraphBase* graph, int input_count)
       : GenericNode<NodeData, Node>(graph, input_count) {}
 
   void Initialize(Operator* op) { set_op(op); }
 
   void CollectProjections(int projection_count, Node** projections);
+  Node* FindProjection(int32_t projection_index);
 };
 
 OStream& operator<<(OStream& os, const Node& n);
 
 typedef GenericGraphVisit::NullNodeVisitor<NodeData, Node> NullNodeVisitor;
 
 typedef zone_allocator<Node*> NodePtrZoneAllocator;
 
 typedef std::set<Node*, std::less<Node*>, NodePtrZoneAllocator> NodeSet;
 typedef NodeSet::iterator NodeSetIter;
@@ skipping 17 matching lines @@
 // Helper to extract parameters from Operator1<*> nodes.
 template <typename T>
 static inline T OpParameter(Node* node) {
   return reinterpret_cast<Operator1<T>*>(node->op())->parameter();
 }
 }
 }
 }  // namespace v8::internal::compiler
 
 #endif  // V8_COMPILER_NODE_H_