Two changes, one a refactoring and one that affects V8's JS semantics....

src/usage-analyzer.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 26 matching lines @@
 // Weight boundaries
 static const int MinWeight = 1;
 static const int MaxWeight = 1000000;
 static const int InitialWeight = 100;
 
 
 class UsageComputer: public AstVisitor {
  public:
   static bool Traverse(AstNode* node);
 
-  void VisitBlock(Block* node);
-  void VisitDeclaration(Declaration* node);
-  void VisitExpressionStatement(ExpressionStatement* node);
-  void VisitEmptyStatement(EmptyStatement* node);
-  void VisitIfStatement(IfStatement* node);
-  void VisitContinueStatement(ContinueStatement* node);
-  void VisitBreakStatement(BreakStatement* node);
-  void VisitReturnStatement(ReturnStatement* node);
-  void VisitWithEnterStatement(WithEnterStatement* node);
-  void VisitWithExitStatement(WithExitStatement* node);
-  void VisitSwitchStatement(SwitchStatement* node);
-  void VisitLoopStatement(LoopStatement* node);
-  void VisitForInStatement(ForInStatement* node);
-  void VisitTryCatch(TryCatch* node);
-  void VisitTryFinally(TryFinally* node);
-  void VisitDebuggerStatement(DebuggerStatement* node);
-  void VisitFunctionLiteral(FunctionLiteral* node);
-  void VisitFunctionBoilerplateLiteral(FunctionBoilerplateLiteral* node);
-  void VisitConditional(Conditional* node);
-  void VisitSlot(Slot* node);
-  void VisitVariable(Variable* node);
-  void VisitVariableProxy(VariableProxy* node);
-  void VisitLiteral(Literal* node);
-  void VisitRegExpLiteral(RegExpLiteral* node);
-  void VisitObjectLiteral(ObjectLiteral* node);
-  void VisitArrayLiteral(ArrayLiteral* node);
-  void VisitCatchExtensionObject(CatchExtensionObject* node);
-  void VisitAssignment(Assignment* node);
-  void VisitThrow(Throw* node);
-  void VisitProperty(Property* node);
-  void VisitCall(Call* node);
-  void VisitCallNew(CallNew* node);
-  void VisitCallRuntime(CallRuntime* node);
-  void VisitUnaryOperation(UnaryOperation* node);
-  void VisitCountOperation(CountOperation* node);
-  void VisitBinaryOperation(BinaryOperation* node);
-  void VisitCompareOperation(CompareOperation* node);
-  void VisitThisFunction(ThisFunction* node);
+  // AST node visit functions.
+#define DECLARE_VISIT(type) void Visit##type(type* node);
+  AST_NODE_LIST(DECLARE_VISIT)
+#undef DECLARE_VISIT
+
+  void VisitVariable(Variable* var);
 
  private:
   int weight_;
   bool is_write_;
 
   UsageComputer(int weight, bool is_write);
   virtual ~UsageComputer();
 
   // Helper functions
   void RecordUses(UseCount* uses);
@@ skipping 227 matching lines @@
 }
 
 
 void UsageComputer::VisitCall(Call* node) {
   Read(node->expression());
   ReadList(node->arguments());
 }
 
 
 void UsageComputer::VisitCallNew(CallNew* node) {
-  VisitCall(node);
+  Read(node->expression());
+  ReadList(node->arguments());
 }
 
 
 void UsageComputer::VisitCallRuntime(CallRuntime* node) {
   ReadList(node->arguments());
 }
 
 
 void UsageComputer::VisitUnaryOperation(UnaryOperation* node) {
   Read(node->expression());
@@ skipping 94 matching lines @@
 // ----------------------------------------------------------------------------
 // Interface to variable usage analysis
 
 bool AnalyzeVariableUsage(FunctionLiteral* lit) {
   if (!FLAG_usage_computation) return true;
   HistogramTimerScope timer(&Counters::usage_analysis);
   return UsageComputer::Traverse(lit);
 }
 
 } }  // namespace v8::internal