Revert of Revert of [turbofan] Improve memory layout of Node class.

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 "src/compiler/opcodes.h"
 #include "src/compiler/operator.h"
 #include "src/types-inl.h"
@@ skipping 150 matching lines @@
     Use* use;
 
     void Update(Node* new_to);
   };
 
   inline Node(NodeId id, const Operator* op, int input_count,
               int reserve_input_count);
 
   inline void EnsureAppendableInputs(Zone* zone);
 
-  Input* GetInputRecordPtr(int index) const {
-    if (has_appendable_inputs()) {
-      return &((*inputs_.appendable_)[index]);
-    } else {
-      return &inputs_.static_[index];
-    }
+  Input* GetInputRecordPtr(int index) {
+    return has_appendable_inputs() ? &((*inputs_.appendable_)[index])
+                                   : &inputs_.static_[index];
+  }
+  const Input* GetInputRecordPtr(int index) const {
+    return has_appendable_inputs() ? &((*inputs_.appendable_)[index])
+                                   : &inputs_.static_[index];
   }
 
   inline void AppendUse(Use* const use);
   inline void RemoveUse(Use* const use);
 
   void* operator new(size_t, void* location) { return location; }
 
   typedef ZoneDeque<Input> InputDeque;
 
   // Only NodeProperties should manipulate the bounds.
@@ skipping 30 matching lines @@
   typedef BitField<unsigned, 0, 29> InputCountField;
   typedef BitField<unsigned, 29, 2> ReservedInputCountField;
   typedef BitField<unsigned, 31, 1> HasAppendableInputsField;
   static const int kDefaultReservedInputs = ReservedInputCountField::kMax;
 
   const Operator* op_;
   Bounds bounds_;
   Mark mark_;
   NodeId const id_;
   unsigned bit_field_;
+  Use* first_use_;
+  Use* last_use_;
   union {
     // When a node is initially allocated, it uses a static buffer to hold its
     // inputs under the assumption that the number of outputs will not increase.
     // When the first input is appended, the static buffer is converted into a
     // deque to allow for space-efficient growing.
-    Input* static_;
+    Input static_[1];
     InputDeque* appendable_;
   } inputs_;
-  Use* first_use_;
-  Use* last_use_;
 
   friend class Edge;
   friend class NodeMarkerBase;
   friend class NodeProperties;
 
   DISALLOW_COPY_AND_ASSIGN(Node);
 };
 
 
 std::ostream& operator<<(std::ostream& os, const Node& n);
@@ skipping 229 matching lines @@
 
 void Node::ReplaceInput(int index, Node* new_to) {
   GetInputRecordPtr(index)->Update(new_to);
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_NODE_H_