Do not save/restore AST id generator.

AST ids only need to be unique, so there is no need to fiddle around with them.

R=dslomov@chromium.org

Review URL: https://codereview.chromium.org/633053002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24433 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/parser.cc

@@ -342,25 +342,6 @@ class TargetScope BASE_EMBEDDED {
 // ----------------------------------------------------------------------------
 // Implementation of Parser
 
-class ParserTraits::Checkpoint
-    : public ParserBase<ParserTraits>::CheckpointBase {
- public:
-  explicit Checkpoint(ParserBase<ParserTraits>* parser)
-      : CheckpointBase(parser), parser_(parser) {
-    saved_ast_node_id_gen_ = *parser_->ast_node_id_gen_;
-  }
-
-  void Restore() {
-    CheckpointBase::Restore();
-    *parser_->ast_node_id_gen_ = saved_ast_node_id_gen_;
-  }
-
- private:
-  ParserBase<ParserTraits>* parser_;
-  AstNode::IdGen saved_ast_node_id_gen_;
-};
-
-
 bool ParserTraits::IsEvalOrArguments(const AstRawString* identifier) const {
   return identifier == parser_->ast_value_factory()->eval_string() ||
          identifier == parser_->ast_value_factory()->arguments_string();

src/parser.h

@@ -374,8 +374,6 @@ class ParserTraits {
     typedef AstNodeFactory<AstConstructionVisitor> Factory;
   };
 
-  class Checkpoint;
-
   explicit ParserTraits(Parser* parser) : parser_(parser) {}
 
   // Custom operations executed when FunctionStates are created and destructed.

src/preparser.cc

@@ -32,13 +32,6 @@ int isfinite(double value);
 namespace v8 {
 namespace internal {
 
-class PreParserTraits::Checkpoint
-    : public ParserBase<PreParserTraits>::CheckpointBase {
- public:
-  explicit Checkpoint(ParserBase<PreParserTraits>* parser)
-      : ParserBase<PreParserTraits>::CheckpointBase(parser) {}
-};
-
 void PreParserTraits::ReportMessageAt(Scanner::Location location,
                                       const char* message,
                                       const char* arg,

src/preparser.h

@@ -123,8 +123,6 @@ class ParserBase : public Traits {
   }
 
  protected:
-  friend class Traits::Checkpoint;
-
   enum AllowEvalOrArgumentsAsIdentifier {
     kAllowEvalOrArguments,
     kDontAllowEvalOrArguments
@@ -135,7 +133,7 @@ class ParserBase : public Traits {
     PARSE_EAGERLY
   };
 
-  class CheckpointBase;
+  class Checkpoint;
   class ObjectLiteralChecker;
 
   // ---------------------------------------------------------------------------
@@ -235,16 +233,16 @@ class ParserBase : public Traits {
     typename Traits::Type::Factory factory_;
 
     friend class ParserTraits;
-    friend class CheckpointBase;
+    friend class Checkpoint;
   };
 
   // Annoyingly, arrow functions first parse as comma expressions, then when we
   // see the => we have to go back and reinterpret the arguments as being formal
   // parameters.  To do so we need to reset some of the parser state back to
   // what it was before the arguments were first seen.
-  class CheckpointBase BASE_EMBEDDED {
+  class Checkpoint BASE_EMBEDDED {
    public:
-    explicit CheckpointBase(ParserBase* parser) {
+    explicit Checkpoint(ParserBase* parser) {
       function_state_ = parser->function_state_;
       next_materialized_literal_index_ =
           function_state_->next_materialized_literal_index_;
@@ -1149,8 +1147,6 @@ class PreParserTraits {
     typedef PreParserFactory Factory;
   };
 
-  class Checkpoint;
-
   explicit PreParserTraits(PreParser* pre_parser) : pre_parser_(pre_parser) {}
 
   // Custom operations executed when FunctionStates are created and
@@ -2164,7 +2160,7 @@ ParserBase<Traits>::ParseAssignmentExpression(bool accept_IN, bool* ok) {
   }
 
   if (fni_ != NULL) fni_->Enter();
-  typename Traits::Checkpoint checkpoint(this);
+  ParserBase<Traits>::Checkpoint checkpoint(this);
   ExpressionT expression =
       this->ParseConditionalExpression(accept_IN, CHECK_OK);