Create an abstraction for the string type flags so that they can be cached....

src/parser.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 719 matching lines @@
   return !scanner().stack_overflow();
 }
 
 
 FunctionLiteral* Parser::ParseProgram(Handle<String> source,
                                       unibrow::CharacterStream* stream,
                                       bool in_global_context) {
   ZoneScope zone_scope(DONT_DELETE_ON_EXIT);
 
   StatsRateScope timer(&Counters::parse);
-  Counters::total_parse_size.Increment(source->length());
+  StringShape shape(*source);
+  Counters::total_parse_size.Increment(source->length(shape));
 
   // Initialize parser state.
-  source->TryFlatten();
+  source->TryFlatten(shape);
   scanner_.Init(source, stream, 0);
   ASSERT(target_stack_ == NULL);
 
   // Compute the parsing mode.
   mode_ = FLAG_lazy ? PARSE_LAZILY : PARSE_EAGERLY;
   if (allow_natives_syntax_ || extension_ != NULL) mode_ = PARSE_EAGERLY;
 
   Scope::Type type =
     in_global_context
       ? Scope::GLOBAL_SCOPE
       : Scope::EVAL_SCOPE;
   Handle<String> no_name = factory()->EmptySymbol();
 
   FunctionLiteral* result = NULL;
   { Scope* scope = factory()->NewScope(top_scope_, type, inside_with());
     LexicalScope lexical_scope(this, scope);
     TemporaryScope temp_scope(this);
     ZoneListWrapper<Statement> body(16);
     bool ok = true;
     ParseSourceElements(&body, Token::EOS, &ok);
     if (ok) {
       result = NEW(FunctionLiteral(no_name, top_scope_,
                                    body.elements(),
                                    temp_scope.materialized_literal_count(),
                                    temp_scope.contains_array_literal(),
                                    temp_scope.expected_property_count(),
-                                   0, 0, source->length(), false));
+                                   0, 0, source->length(shape), false));
     } else if (scanner().stack_overflow()) {
       Top::StackOverflow();
     }
   }
 
   // Make sure the target stack is empty.
   ASSERT(target_stack_ == NULL);
 
   // If there was a syntax error we have to get rid of the AST
   // and it is not safe to do so before the scope has been deleted.
   if (result == NULL) zone_scope.DeleteOnExit();
   return result;
 }
 
 
 FunctionLiteral* Parser::ParseLazy(Handle<String> source,
                                    Handle<String> name,
                                    int start_position,
                                    bool is_expression) {
   ZoneScope zone_scope(DONT_DELETE_ON_EXIT);
   StatsRateScope timer(&Counters::parse_lazy);
-  Counters::total_parse_size.Increment(source->length());
+  StringShape shape(*source);
+  source->TryFlatten(shape);
+  Counters::total_parse_size.Increment(source->length(shape));
   SafeStringInputBuffer buffer(source.location());
 
   // Initialize parser state.
-  source->TryFlatten();
   scanner_.Init(source, &buffer, start_position);
   ASSERT(target_stack_ == NULL);
   mode_ = PARSE_EAGERLY;
 
   // Place holder for the result.
   FunctionLiteral* result = NULL;
 
   {
     // Parse the function literal.
     Handle<String> no_name = factory()->EmptySymbol();
@@ skipping 2447 matching lines @@
                        start_position,
                        is_expression);
   return result;
 }
 
 
 #undef NEW
 
 
 } }  // namespace v8::internal