Proof of concept: API for doing only one parsing pass instead of first preparsing and then parsing.

src/preparser.h

 // Copyright 2012 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 @@
 
 namespace v8 {
 namespace internal {
 
 // Common base class shared between parser and pre-parser.
 template <typename Traits>
 class ParserBase : public Traits {
  public:
   ParserBase(Scanner* scanner, uintptr_t stack_limit,
              v8::Extension* extension,
+             ParserRecorder* log,
              typename Traits::Type::Zone* zone,
              typename Traits::Type::Parser this_object)
       : Traits(this_object),
         parenthesized_function_(false),
         scope_(NULL),
         function_state_(NULL),
         extension_(extension),
         fni_(NULL),
+        log_(log),
         scanner_(scanner),
         stack_limit_(stack_limit),
         stack_overflow_(false),
         allow_lazy_(false),
         allow_natives_syntax_(false),
         allow_generators_(false),
         allow_for_of_(false),
         zone_(zone) { }
 
   // Getters that indicate whether certain syntactical constructs are
@@ skipping 336 matching lines @@
   // If true, the next (and immediately following) function literal is
   // preceded by a parenthesis.
   // Heuristically that means that the function will be called immediately,
   // so never lazily compile it.
   bool parenthesized_function_;
 
   typename Traits::Type::Scope* scope_;  // Scope stack.
   FunctionState* function_state_;  // Function state stack.
   v8::Extension* extension_;
   FuncNameInferrer* fni_;
+  ParserRecorder* log_;
 
  private:
   Scanner* scanner_;
   uintptr_t stack_limit_;
   bool stack_overflow_;
 
   bool allow_lazy_;
   bool allow_natives_syntax_;
   bool allow_generators_;
   bool allow_for_of_;
@@ skipping 382 matching lines @@
 class PreParser : public ParserBase<PreParserTraits> {
  public:
   typedef PreParserIdentifier Identifier;
   typedef PreParserExpression Expression;
 
   enum PreParseResult {
     kPreParseStackOverflow,
     kPreParseSuccess
   };
 
-  PreParser(Scanner* scanner,
-            ParserRecorder* log,
-            uintptr_t stack_limit)
-      : ParserBase<PreParserTraits>(scanner, stack_limit, NULL, NULL, this),
-        log_(log) {}
+  PreParser(Scanner* scanner, ParserRecorder* log, uintptr_t stack_limit)
+      : ParserBase<PreParserTraits>(scanner, stack_limit, NULL, log, NULL,
+                                    this) {}
 
   // Pre-parse the program from the character stream; returns true on
   // success (even if parsing failed, the pre-parse data successfully
   // captured the syntax error), and false if a stack-overflow happened
   // during parsing.
   PreParseResult PreParseProgram() {
     PreParserScope scope(scope_, GLOBAL_SCOPE);
     FunctionState top_scope(&function_state_, &scope_, &scope, NULL);
     bool ok = true;
     int start_position = scanner()->peek_location().beg_pos;
@@ skipping 142 matching lines @@
       FunctionLiteral::FunctionType function_type,
       bool* ok);
   void ParseLazyFunctionLiteralBody(bool* ok);
 
   // Logs the currently parsed literal as a symbol in the preparser data.
   void LogSymbol();
   // Log the currently parsed string literal.
   Expression GetStringSymbol();
 
   bool CheckInOrOf(bool accept_OF);
-
-  ParserRecorder* log_;
 };
 
 
 template<class Traits>
 ParserBase<Traits>::FunctionState::FunctionState(
     FunctionState** function_state_stack,
     typename Traits::Type::Scope** scope_stack,
     typename Traits::Type::Scope* scope,
     typename Traits::Type::Zone* extra_param)
     : next_materialized_literal_index_(JSFunction::kLiteralsPrefixSize),
@@ skipping 549 matching lines @@
                                "accessor_get_set");
     }
     *ok = false;
   }
 }
 
 
 } }  // v8::internal
 
 #endif  // V8_PREPARSER_H