Track usage of "this" and "arguments" in Scope

src/ast-value-factory.h

 // Copyright 2014 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 70 matching lines @@
   bool is_one_byte() const { return is_one_byte_; }
   bool IsOneByteEqualTo(const char* data) const;
   uint16_t FirstCharacter() const {
     if (is_one_byte_)
       return literal_bytes_[0];
     const uint16_t* c =
         reinterpret_cast<const uint16_t*>(literal_bytes_.start());
     return *c;
   }
 
+  V8_INLINE bool IsArguments(AstValueFactory* ast_value_factory) const;
+
   // For storing AstRawStrings in a hash map.
   uint32_t hash() const {
     return hash_;
   }
   static bool Compare(void* a, void* b);
 
  private:
   friend class AstValueFactory;
   friend class AstRawStringInternalizationKey;
 
@@ skipping 229 matching lines @@
   Isolate* isolate_;
 
   uint32_t hash_seed_;
 
 #define F(name, str) \
   const AstRawString* name##_string_;
   STRING_CONSTANTS(F)
 #undef F
 };
 
+
+bool AstRawString::IsArguments(AstValueFactory* ast_value_factory) const {
+  return ast_value_factory->arguments_string() == this;
+}
+
 } }  // namespace v8::internal
 
 #undef STRING_CONSTANTS
 
 #endif  // V8_AST_VALUE_FACTORY_H_