Parser: Delay internalizing strings and values.

src/ast.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_AST_H_
 #define V8_AST_H_
 
 #include "src/v8.h"
 
 #include "src/assembler.h"
+#include "src/ast-value-factory.h"
 #include "src/factory.h"
 #include "src/feedback-slots.h"
 #include "src/isolate.h"
 #include "src/jsregexp.h"
 #include "src/list-inl.h"
 #include "src/runtime.h"
 #include "src/small-pointer-list.h"
 #include "src/smart-pointers.h"
 #include "src/token.h"
 #include "src/types.h"
@@ skipping 339 matching lines @@
   // TODO(rossberg): this should move to its own AST node eventually.
   virtual void RecordToBooleanTypeFeedback(TypeFeedbackOracle* oracle);
   byte to_boolean_types() const { return to_boolean_types_; }
 
   BailoutId id() const { return id_; }
   TypeFeedbackId test_id() const { return test_id_; }
 
  protected:
   Expression(Zone* zone, int pos)
       : AstNode(pos),
+        zone_(zone),
         bounds_(Bounds::Unbounded(zone)),
         id_(GetNextId(zone)),
         test_id_(GetNextId(zone)) {}
   void set_to_boolean_types(byte types) { to_boolean_types_ = types; }
 
+  Zone* zone_;
+
  private:
   Bounds bounds_;
   byte to_boolean_types_;
 
   const BailoutId id_;
   const TypeFeedbackId test_id_;
 };
 
 
 class BreakableStatement : public Statement {
  public:
   enum BreakableType {
     TARGET_FOR_ANONYMOUS,
     TARGET_FOR_NAMED_ONLY
   };
 
   // The labels associated with this statement. May be NULL;
   // if it is != NULL, guaranteed to contain at least one entry.
-  ZoneStringList* labels() const { return labels_; }
+  ZoneList<const AstString*>* labels() const { return labels_; }
 
   // Type testing & conversion.
   virtual BreakableStatement* AsBreakableStatement() V8_FINAL V8_OVERRIDE {
     return this;
   }
 
   // Code generation
   Label* break_target() { return &break_target_; }
 
   // Testers.
   bool is_target_for_anonymous() const {
     return breakable_type_ == TARGET_FOR_ANONYMOUS;
   }
 
   BailoutId EntryId() const { return entry_id_; }
   BailoutId ExitId() const { return exit_id_; }
 
  protected:
   BreakableStatement(
-      Zone* zone, ZoneStringList* labels,
+      Zone* zone, ZoneList<const AstString*>* labels,
       BreakableType breakable_type, int position)
       : Statement(zone, position),
         labels_(labels),
         breakable_type_(breakable_type),
         entry_id_(GetNextId(zone)),
         exit_id_(GetNextId(zone)) {
     ASSERT(labels == NULL || labels->length() > 0);
   }
 
 
  private:
-  ZoneStringList* labels_;
+  ZoneList<const AstString*>* labels_;
   BreakableType breakable_type_;
   Label break_target_;
   const BailoutId entry_id_;
   const BailoutId exit_id_;
 };
 
 
 class Block V8_FINAL : public BreakableStatement {
  public:
   DECLARE_NODE_TYPE(Block)
@@ skipping 10 matching lines @@
   virtual bool IsJump() const V8_OVERRIDE {
     return !statements_.is_empty() && statements_.last()->IsJump()
         && labels() == NULL;  // Good enough as an approximation...
   }
 
   Scope* scope() const { return scope_; }
   void set_scope(Scope* scope) { scope_ = scope; }
 
  protected:
   Block(Zone* zone,
-        ZoneStringList* labels,
+        ZoneList<const AstString*>* labels,
         int capacity,
         bool is_initializer_block,
         int pos)
       : BreakableStatement(zone, labels, TARGET_FOR_NAMED_ONLY, pos),
         statements_(capacity, zone),
         is_initializer_block_(is_initializer_block),
         decls_id_(GetNextId(zone)),
         scope_(NULL) {
   }
 
@@ skipping 188 matching lines @@
  private:
   VariableProxy* proxy_;
 };
 
 
 class ModulePath V8_FINAL : public Module {
  public:
   DECLARE_NODE_TYPE(ModulePath)
 
   Module* module() const { return module_; }
-  Handle<String> name() const { return name_; }
+  Handle<String> name() const { return name_->string(); }
 
  protected:
-  ModulePath(Zone* zone, Module* module, Handle<String> name, int pos)
-      : Module(zone, pos),
-        module_(module),
-        name_(name) {
-  }
+  ModulePath(Zone* zone, Module* module, const AstString* name, int pos)
+      : Module(zone, pos), module_(module), name_(name) {}
 
  private:
   Module* module_;
-  Handle<String> name_;
+  const AstString* name_;
 };
 
 
 class ModuleUrl V8_FINAL : public Module {
  public:
   DECLARE_NODE_TYPE(ModuleUrl)
 
   Handle<String> url() const { return url_; }
 
  protected:
@@ skipping 36 matching lines @@
   Statement* body() const { return body_; }
 
   BailoutId OsrEntryId() const { return osr_entry_id_; }
   virtual BailoutId ContinueId() const = 0;
   virtual BailoutId StackCheckId() const = 0;
 
   // Code generation
   Label* continue_target()  { return &continue_target_; }
 
  protected:
-  IterationStatement(Zone* zone, ZoneStringList* labels, int pos)
+  IterationStatement(Zone* zone, ZoneList<const AstString*>* labels, int pos)
       : BreakableStatement(zone, labels, TARGET_FOR_ANONYMOUS, pos),
         body_(NULL),
         osr_entry_id_(GetNextId(zone)) {
   }
 
   void Initialize(Statement* body) {
     body_ = body;
   }
 
  private:
@@ skipping 13 matching lines @@
     cond_ = cond;
   }
 
   Expression* cond() const { return cond_; }
 
   virtual BailoutId ContinueId() const V8_OVERRIDE { return continue_id_; }
   virtual BailoutId StackCheckId() const V8_OVERRIDE { return back_edge_id_; }
   BailoutId BackEdgeId() const { return back_edge_id_; }
 
  protected:
-  DoWhileStatement(Zone* zone, ZoneStringList* labels, int pos)
+  DoWhileStatement(Zone* zone, ZoneList<const AstString*>* labels, int pos)
       : IterationStatement(zone, labels, pos),
         cond_(NULL),
         continue_id_(GetNextId(zone)),
         back_edge_id_(GetNextId(zone)) {
   }
 
  private:
   Expression* cond_;
 
   const BailoutId continue_id_;
@@ skipping 16 matching lines @@
   }
   void set_may_have_function_literal(bool value) {
     may_have_function_literal_ = value;
   }
 
   virtual BailoutId ContinueId() const V8_OVERRIDE { return EntryId(); }
   virtual BailoutId StackCheckId() const V8_OVERRIDE { return body_id_; }
   BailoutId BodyId() const { return body_id_; }
 
  protected:
-  WhileStatement(Zone* zone, ZoneStringList* labels, int pos)
+  WhileStatement(Zone* zone, ZoneList<const AstString*>* labels, int pos)
       : IterationStatement(zone, labels, pos),
         cond_(NULL),
         may_have_function_literal_(true),
         body_id_(GetNextId(zone)) {
   }
 
  private:
   Expression* cond_;
 
   // True if there is a function literal subexpression in the condition.
@@ skipping 30 matching lines @@
 
   virtual BailoutId ContinueId() const V8_OVERRIDE { return continue_id_; }
   virtual BailoutId StackCheckId() const V8_OVERRIDE { return body_id_; }
   BailoutId BodyId() const { return body_id_; }
 
   bool is_fast_smi_loop() { return loop_variable_ != NULL; }
   Variable* loop_variable() { return loop_variable_; }
   void set_loop_variable(Variable* var) { loop_variable_ = var; }
 
  protected:
-  ForStatement(Zone* zone, ZoneStringList* labels, int pos)
+  ForStatement(Zone* zone, ZoneList<const AstString*>* labels, int pos)
       : IterationStatement(zone, labels, pos),
         init_(NULL),
         cond_(NULL),
         next_(NULL),
         may_have_function_literal_(true),
         loop_variable_(NULL),
         continue_id_(GetNextId(zone)),
         body_id_(GetNextId(zone)) {
   }
 
@@ skipping 21 matching lines @@
   void Initialize(Expression* each, Expression* subject, Statement* body) {
     IterationStatement::Initialize(body);
     each_ = each;
     subject_ = subject;
   }
 
   Expression* each() const { return each_; }
   Expression* subject() const { return subject_; }
 
  protected:
-  ForEachStatement(Zone* zone, ZoneStringList* labels, int pos)
-      : IterationStatement(zone, labels, pos),
-        each_(NULL),
-        subject_(NULL) {
-  }
+  ForEachStatement(Zone* zone, ZoneList<const AstString*>* labels, int pos)
+      : IterationStatement(zone, labels, pos), each_(NULL), subject_(NULL) {}
 
  private:
   Expression* each_;
   Expression* subject_;
 };
 
 
 class ForInStatement V8_FINAL : public ForEachStatement,
     public FeedbackSlotInterface {
  public:
@@ skipping 15 matching lines @@
   enum ForInType { FAST_FOR_IN, SLOW_FOR_IN };
   ForInType for_in_type() const { return for_in_type_; }
   void set_for_in_type(ForInType type) { for_in_type_ = type; }
 
   BailoutId BodyId() const { return body_id_; }
   BailoutId PrepareId() const { return prepare_id_; }
   virtual BailoutId ContinueId() const V8_OVERRIDE { return EntryId(); }
   virtual BailoutId StackCheckId() const V8_OVERRIDE { return body_id_; }
 
  protected:
-  ForInStatement(Zone* zone, ZoneStringList* labels, int pos)
+  ForInStatement(Zone* zone, ZoneList<const AstString*>* labels, int pos)
       : ForEachStatement(zone, labels, pos),
         for_in_type_(SLOW_FOR_IN),
         for_in_feedback_slot_(kInvalidFeedbackSlot),
         body_id_(GetNextId(zone)),
         prepare_id_(GetNextId(zone)) {
   }
 
   ForInType for_in_type_;
   int for_in_feedback_slot_;
   const BailoutId body_id_;
@@ skipping 49 matching lines @@
   Expression* assign_each() const {
     return assign_each_;
   }
 
   virtual BailoutId ContinueId() const V8_OVERRIDE { return EntryId(); }
   virtual BailoutId StackCheckId() const V8_OVERRIDE { return BackEdgeId(); }
 
   BailoutId BackEdgeId() const { return back_edge_id_; }
 
  protected:
-  ForOfStatement(Zone* zone, ZoneStringList* labels, int pos)
+  ForOfStatement(Zone* zone, ZoneList<const AstString*>* labels, int pos)
       : ForEachStatement(zone, labels, pos),
         assign_iterator_(NULL),
         next_result_(NULL),
         result_done_(NULL),
         assign_each_(NULL),
         back_edge_id_(GetNextId(zone)) {
   }
 
   Expression* assign_iterable_;
   Expression* assign_iterator_;
@@ skipping 140 matching lines @@
 
   void Initialize(Expression* tag, ZoneList<CaseClause*>* cases) {
     tag_ = tag;
     cases_ = cases;
   }
 
   Expression* tag() const { return tag_; }
   ZoneList<CaseClause*>* cases() const { return cases_; }
 
  protected:
-  SwitchStatement(Zone* zone, ZoneStringList* labels, int pos)
+  SwitchStatement(Zone* zone, ZoneList<const AstString*>* labels, int pos)
       : BreakableStatement(zone, labels, TARGET_FOR_ANONYMOUS, pos),
         tag_(NULL),
         cases_(NULL) { }
 
  private:
   Expression* tag_;
   ZoneList<CaseClause*>* cases_;
 };
 
 
@@ skipping 159 matching lines @@
  protected:
   explicit EmptyStatement(Zone* zone, int pos): Statement(zone, pos) {}
 };
 
 
 class Literal V8_FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(Literal)
 
   virtual bool IsPropertyName() const V8_OVERRIDE {
-    if (value_->IsInternalizedString()) {
-      uint32_t ignored;
-      return !String::cast(*value_)->AsArrayIndex(&ignored);
-    }
-    return false;
+    return value_->IsPropertyName();
   }
 
   Handle<String> AsPropertyName() {
     ASSERT(IsPropertyName());
-    return Handle<String>::cast(value_);
+    return Handle<String>::cast(value());
+  }
+
+  const AstString* AsRawPropertyName() {
+    ASSERT(IsPropertyName());
+    return value_->AsString();
   }
 
   virtual bool ToBooleanIsTrue() const V8_OVERRIDE {
-    return value_->BooleanValue();
+    return value()->BooleanValue();
   }
   virtual bool ToBooleanIsFalse() const V8_OVERRIDE {
-    return !value_->BooleanValue();
+    return !value()->BooleanValue();
   }
 
-  Handle<Object> value() const { return value_; }
+  Handle<Object> value() const { return value_->value(); }
+  const AstValue* raw_value() const { return value_; }
 
   // Support for using Literal as a HashMap key. NOTE: Currently, this works
   // only for string and number literals!
   uint32_t Hash() { return ToString()->Hash(); }
 
   static bool Match(void* literal1, void* literal2) {
     Handle<String> s1 = static_cast<Literal*>(literal1)->ToString();
     Handle<String> s2 = static_cast<Literal*>(literal2)->ToString();
     return String::Equals(s1, s2);
   }
 
   TypeFeedbackId LiteralFeedbackId() const { return reuse(id()); }
 
  protected:
-  Literal(Zone* zone, Handle<Object> value, int position)
+  Literal(Zone* zone, const AstValue* value, int position)
       : Expression(zone, position),
         value_(value),
         isolate_(zone->isolate()) { }
 
  private:
   Handle<String> ToString();
 
-  Handle<Object> value_;
+  const AstValue* value_;
   // TODO(dcarney): remove.  this is only needed for Match and Hash.
   Isolate* isolate_;
 };
 
 
 // Base class for literals that needs space in the corresponding JSFunction.
 class MaterializedLiteral : public Expression {
  public:
   virtual MaterializedLiteral* AsMaterializedLiteral() { return this; }
 
@@ skipping 50 matching lines @@
 class ObjectLiteralProperty V8_FINAL : public ZoneObject {
  public:
   enum Kind {
     CONSTANT,              // Property with constant value (compile time).
     COMPUTED,              // Property with computed value (execution time).
     MATERIALIZED_LITERAL,  // Property value is a materialized literal.
     GETTER, SETTER,        // Property is an accessor function.
     PROTOTYPE              // Property is __proto__.
   };
 
-  ObjectLiteralProperty(Zone* zone, Literal* key, Expression* value);
+  ObjectLiteralProperty(Zone* zone, AstValueFactory* ast_value_factory,
+                        Literal* key, Expression* value);
 
   Literal* key() { return key_; }
   Expression* value() { return value_; }
   Kind kind() { return kind_; }
 
   // Type feedback information.
   void RecordTypeFeedback(TypeFeedbackOracle* oracle);
   bool IsMonomorphic() { return !receiver_type_.is_null(); }
   Handle<Map> GetReceiverType() { return receiver_type_; }
 
@@ skipping 78 matching lines @@
   bool may_store_doubles_;
   bool has_function_;
 };
 
 
 // Node for capturing a regexp literal.
 class RegExpLiteral V8_FINAL : public MaterializedLiteral {
  public:
   DECLARE_NODE_TYPE(RegExpLiteral)
 
-  Handle<String> pattern() const { return pattern_; }
-  Handle<String> flags() const { return flags_; }
+  Handle<String> pattern() const { return pattern_->string(); }
+  Handle<String> flags() const { return flags_->string(); }
 
  protected:
   RegExpLiteral(Zone* zone,
-                Handle<String> pattern,
-                Handle<String> flags,
+                const AstString* pattern,
+                const AstString* flags,
                 int literal_index,
                 int pos)
       : MaterializedLiteral(zone, literal_index, pos),
         pattern_(pattern),
         flags_(flags) {
     set_depth(1);
   }
 
  private:
-  Handle<String> pattern_;
-  Handle<String> flags_;
+  const AstString* pattern_;
+  const AstString* flags_;
 };
 
 
 // An array literal has a literals object that is used
 // for minimizing the work when constructing it at runtime.
 class ArrayLiteral V8_FINAL : public MaterializedLiteral {
  public:
   DECLARE_NODE_TYPE(ArrayLiteral)
 
   Handle<FixedArray> constant_elements() const { return constant_elements_; }
@@ skipping 30 matching lines @@
 
 
 class VariableProxy V8_FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(VariableProxy)
 
   virtual bool IsValidReferenceExpression() const V8_OVERRIDE {
     return var_ == NULL ? true : var_->IsValidReference();
   }
 
-  bool IsVariable(Handle<String> n) const {
-    return !is_this() && name().is_identical_to(n);
-  }
-
   bool IsArguments() const { return var_ != NULL && var_->is_arguments(); }
 
   bool IsLValue() const { return is_lvalue_; }
 
-  Handle<String> name() const { return name_; }
+  Handle<String> name() const { return name_->string(); }
+  const AstString* raw_name() const { return name_; }
   Variable* var() const { return var_; }
   bool is_this() const { return is_this_; }
   Interface* interface() const { return interface_; }
 
 
   void MarkAsTrivial() { is_trivial_ = true; }
   void MarkAsLValue() { is_lvalue_ = true; }
 
   // Bind this proxy to the variable var. Interfaces must match.
   void BindTo(Variable* var);
 
  protected:
   VariableProxy(Zone* zone, Variable* var, int position);
 
   VariableProxy(Zone* zone,
-                Handle<String> name,
+                const AstString* name,
                 bool is_this,
                 Interface* interface,
                 int position);
 
-  Handle<String> name_;
+  const AstString* name_;
   Variable* var_;  // resolved variable, or NULL
   bool is_this_;
   bool is_trivial_;
   // True if this variable proxy is being used in an assignment
   // or with a increment/decrement operator.
   bool is_lvalue_;
   Interface* interface_;
 };
 
 
@@ skipping 225 matching lines @@
 
 
 // The CallRuntime class does not represent any official JavaScript
 // language construct. Instead it is used to call a C or JS function
 // with a set of arguments. This is used from the builtins that are
 // implemented in JavaScript (see "v8natives.js").
 class CallRuntime V8_FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(CallRuntime)
 
-  Handle<String> name() const { return name_; }
+  Handle<String> name() const { return raw_name_->string(); }
+  const AstString* raw_name() const { return raw_name_; }
   const Runtime::Function* function() const { return function_; }
   ZoneList<Expression*>* arguments() const { return arguments_; }
   bool is_jsruntime() const { return function_ == NULL; }
 
   TypeFeedbackId CallRuntimeFeedbackId() const { return reuse(id()); }
 
  protected:
   CallRuntime(Zone* zone,
-              Handle<String> name,
+              const AstString* name,
               const Runtime::Function* function,
               ZoneList<Expression*>* arguments,
               int pos)
       : Expression(zone, pos),
-        name_(name),
+        raw_name_(name),
         function_(function),
         arguments_(arguments) { }
 
  private:
-  Handle<String> name_;
+  const AstString* raw_name_;
   const Runtime::Function* function_;
   ZoneList<Expression*>* arguments_;
 };
 
 
 class UnaryOperation V8_FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(UnaryOperation)
 
   Token::Value op() const { return op_; }
@@ skipping 367 matching lines @@
     kNotParenthesized
   };
 
   enum IsGeneratorFlag {
     kIsGenerator,
     kNotGenerator
   };
 
   DECLARE_NODE_TYPE(FunctionLiteral)
 
-  Handle<String> name() const { return name_; }
+  Handle<String> name() const { return raw_name_->string(); }
+  const AstString* raw_name() const { return raw_name_; }
   Scope* scope() const { return scope_; }
   ZoneList<Statement*>* body() const { return body_; }
   void set_function_token_position(int pos) { function_token_position_ = pos; }
   int function_token_position() const { return function_token_position_; }
   int start_position() const;
   int end_position() const;
   int SourceSize() const { return end_position() - start_position(); }
   bool is_expression() const { return IsExpression::decode(bitfield_); }
   bool is_anonymous() const { return IsAnonymous::decode(bitfield_); }
   StrictMode strict_mode() const;
 
   int materialized_literal_count() { return materialized_literal_count_; }
   int expected_property_count() { return expected_property_count_; }
   int handler_count() { return handler_count_; }
   int parameter_count() { return parameter_count_; }
 
   bool AllowsLazyCompilation();
   bool AllowsLazyCompilationWithoutContext();
 
   void InitializeSharedInfo(Handle<Code> code);
 
   Handle<String> debug_name() const {
-    if (name_->length() > 0) return name_;
+    if (raw_name_ != NULL && !raw_name_->IsEmpty()) {
+      return raw_name_->string();
+    }
     return inferred_name();
   }
 
-  Handle<String> inferred_name() const { return inferred_name_; }
+  Handle<String> inferred_name() const {
+    if (!inferred_name_.is_null()) {
+      ASSERT(raw_inferred_name_ == NULL);
+      return inferred_name_;
+    }
+    if (raw_inferred_name_ != NULL) {
+      return raw_inferred_name_->string();
+    }
+    UNREACHABLE();
+    return Handle<String>();
+  }
+
+  // Only one of {set_inferred_name, set_raw_inferred_name} should be called.
   void set_inferred_name(Handle<String> inferred_name) {
     inferred_name_ = inferred_name;
+    ASSERT(raw_inferred_name_== NULL || raw_inferred_name_->IsEmpty());
+    raw_inferred_name_ = NULL;
+  }
+
+  void set_raw_inferred_name(const AstString* raw_inferred_name) {
+    raw_inferred_name_ = raw_inferred_name;
+    ASSERT(inferred_name_.is_null());
+    inferred_name_ = Handle<String>();
   }
 
   // shared_info may be null if it's not cached in full code.
   Handle<SharedFunctionInfo> shared_info() { return shared_info_; }
 
   bool pretenure() { return Pretenure::decode(bitfield_); }
   void set_pretenure() { bitfield_ |= Pretenure::encode(true); }
 
   bool has_duplicate_parameters() {
     return HasDuplicateParameters::decode(bitfield_);
@@ skipping 26 matching lines @@
     return ast_properties_.feedback_slots();
   }
   bool dont_optimize() { return dont_optimize_reason_ != kNoReason; }
   BailoutReason dont_optimize_reason() { return dont_optimize_reason_; }
   void set_dont_optimize_reason(BailoutReason reason) {
     dont_optimize_reason_ = reason;
   }
 
  protected:
   FunctionLiteral(Zone* zone,
-                  Handle<String> name,
+                  const AstString* name,
+                  AstValueFactory* ast_value_factory,
                   Scope* scope,
                   ZoneList<Statement*>* body,
                   int materialized_literal_count,
                   int expected_property_count,
                   int handler_count,
                   int parameter_count,
                   FunctionType function_type,
                   ParameterFlag has_duplicate_parameters,
                   IsFunctionFlag is_function,
                   IsParenthesizedFlag is_parenthesized,
                   IsGeneratorFlag is_generator,
                   int position)
       : Expression(zone, position),
-        name_(name),
+        raw_name_(name),
         scope_(scope),
         body_(body),
-        inferred_name_(zone->isolate()->factory()->empty_string()),
+        raw_inferred_name_(ast_value_factory->empty_string()),
         dont_optimize_reason_(kNoReason),
         materialized_literal_count_(materialized_literal_count),
         expected_property_count_(expected_property_count),
         handler_count_(handler_count),
         parameter_count_(parameter_count),
         function_token_position_(RelocInfo::kNoPosition) {
     bitfield_ =
         IsExpression::encode(function_type != DECLARATION) |
         IsAnonymous::encode(function_type == ANONYMOUS_EXPRESSION) |
         Pretenure::encode(false) |
         HasDuplicateParameters::encode(has_duplicate_parameters) |
         IsFunction::encode(is_function) |
         IsParenthesized::encode(is_parenthesized) |
         IsGenerator::encode(is_generator);
   }
 
  private:
+  const AstString* raw_name_;
   Handle<String> name_;
   Handle<SharedFunctionInfo> shared_info_;
   Scope* scope_;
   ZoneList<Statement*>* body_;
+  const AstString* raw_inferred_name_;
   Handle<String> inferred_name_;
   AstProperties ast_properties_;
   BailoutReason dont_optimize_reason_;
 
   int materialized_literal_count_;
   int expected_property_count_;
   int handler_count_;
   int parameter_count_;
   int function_token_position_;
 
   unsigned bitfield_;
   class IsExpression: public BitField<bool, 0, 1> {};
   class IsAnonymous: public BitField<bool, 1, 1> {};
   class Pretenure: public BitField<bool, 2, 1> {};
   class HasDuplicateParameters: public BitField<ParameterFlag, 3, 1> {};
   class IsFunction: public BitField<IsFunctionFlag, 4, 1> {};
   class IsParenthesized: public BitField<IsParenthesizedFlag, 5, 1> {};
   class IsGenerator: public BitField<IsGeneratorFlag, 6, 1> {};
 };
 
 
 class NativeFunctionLiteral V8_FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(NativeFunctionLiteral)
 
-  Handle<String> name() const { return name_; }
+  Handle<String> name() const { return name_->string(); }
   v8::Extension* extension() const { return extension_; }
 
  protected:
-  NativeFunctionLiteral(
-      Zone* zone, Handle<String> name, v8::Extension* extension, int pos)
+  NativeFunctionLiteral(Zone* zone, const AstString* name,
+                        v8::Extension* extension, int pos)
       : Expression(zone, pos), name_(name), extension_(extension) {}
 
  private:
-  Handle<String> name_;
+  const AstString* name_;
   v8::Extension* extension_;
 };
 
 
 class ThisFunction V8_FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(ThisFunction)
 
  protected:
   explicit ThisFunction(Zone* zone, int pos): Expression(zone, pos) {}
@@ skipping 471 matching lines @@
 };
 
 
 
 // ----------------------------------------------------------------------------
 // AstNode factory
 
 template<class Visitor>
 class AstNodeFactory V8_FINAL BASE_EMBEDDED {
  public:
-  explicit AstNodeFactory(Zone* zone) : zone_(zone) { }
+  explicit AstNodeFactory(Zone* zone, AstValueFactory* ast_value_factory)
+      : zone_(zone), ast_value_factory_(ast_value_factory) {}
 
   Visitor* visitor() { return &visitor_; }
 
 #define VISIT_AND_RETURN(NodeType, node) \
   visitor_.Visit##NodeType((node)); \
   return node;
 
   VariableDeclaration* NewVariableDeclaration(VariableProxy* proxy,
                                               VariableMode mode,
                                               Scope* scope,
@@ skipping 43 matching lines @@
     ModuleLiteral* module =
         new(zone_) ModuleLiteral(zone_, body, interface, pos);
     VISIT_AND_RETURN(ModuleLiteral, module)
   }
 
   ModuleVariable* NewModuleVariable(VariableProxy* proxy, int pos) {
     ModuleVariable* module = new(zone_) ModuleVariable(zone_, proxy, pos);
     VISIT_AND_RETURN(ModuleVariable, module)
   }
 
-  ModulePath* NewModulePath(Module* origin, Handle<String> name, int pos) {
-    ModulePath* module = new(zone_) ModulePath(zone_, origin, name, pos);
+  ModulePath* NewModulePath(Module* origin, const AstString* name, int pos) {
+    ModulePath* module = new (zone_) ModulePath(zone_, origin, name, pos);
     VISIT_AND_RETURN(ModulePath, module)
   }
 
   ModuleUrl* NewModuleUrl(Handle<String> url, int pos) {
     ModuleUrl* module = new(zone_) ModuleUrl(zone_, url, pos);
     VISIT_AND_RETURN(ModuleUrl, module)
   }
 
-  Block* NewBlock(ZoneStringList* labels,
+  Block* NewBlock(ZoneList<const AstString*>* labels,
                   int capacity,
                   bool is_initializer_block,
                   int pos) {
     Block* block = new(zone_) Block(
         zone_, labels, capacity, is_initializer_block, pos);
     VISIT_AND_RETURN(Block, block)
   }
 
 #define STATEMENT_WITH_LABELS(NodeType) \
-  NodeType* New##NodeType(ZoneStringList* labels, int pos) { \
+  NodeType* New##NodeType(ZoneList<const AstString*>* labels, int pos) { \
     NodeType* stmt = new(zone_) NodeType(zone_, labels, pos); \
     VISIT_AND_RETURN(NodeType, stmt); \
   }
   STATEMENT_WITH_LABELS(DoWhileStatement)
   STATEMENT_WITH_LABELS(WhileStatement)
   STATEMENT_WITH_LABELS(ForStatement)
   STATEMENT_WITH_LABELS(SwitchStatement)
 #undef STATEMENT_WITH_LABELS
 
   ForEachStatement* NewForEachStatement(ForEachStatement::VisitMode visit_mode,
-                                        ZoneStringList* labels,
+                                        ZoneList<const AstString*>* labels,
                                         int pos) {
     switch (visit_mode) {
       case ForEachStatement::ENUMERATE: {
         ForInStatement* stmt = new(zone_) ForInStatement(zone_, labels, pos);
         VISIT_AND_RETURN(ForInStatement, stmt);
       }
       case ForEachStatement::ITERATE: {
         ForOfStatement* stmt = new(zone_) ForOfStatement(zone_, labels, pos);
         VISIT_AND_RETURN(ForOfStatement, stmt);
       }
@@ skipping 76 matching lines @@
     return new(zone_) EmptyStatement(zone_, pos);
   }
 
   CaseClause* NewCaseClause(
       Expression* label, ZoneList<Statement*>* statements, int pos) {
     CaseClause* clause =
         new(zone_) CaseClause(zone_, label, statements, pos);
     VISIT_AND_RETURN(CaseClause, clause)
   }
 
-  Literal* NewLiteral(Handle<Object> handle, int pos) {
-    Literal* lit = new(zone_) Literal(zone_, handle, pos);
+  Literal* NewStringLiteral(const AstString* string, int pos) {
+    Literal* lit =
+        new (zone_) Literal(zone_, ast_value_factory_->NewString(string), pos);
+    VISIT_AND_RETURN(Literal, lit)
+  }
+
+  // A JavaScript symbol (ECMA-262 edition 6).
+  Literal* NewSymbolLiteral(const char* name, int pos) {
+    Literal* lit =
+        new (zone_) Literal(zone_, ast_value_factory_->NewSymbol(name), pos);
     VISIT_AND_RETURN(Literal, lit)
   }
 
   Literal* NewNumberLiteral(double number, int pos) {
-    return NewLiteral(
-        zone_->isolate()->factory()->NewNumber(number, TENURED), pos);
+    Literal* lit = new (zone_)
+        Literal(zone_, ast_value_factory_->NewNumber(number), pos);
+    VISIT_AND_RETURN(Literal, lit)
+  }
+
+  Literal* NewSmiLiteral(int number, int pos) {
+    Literal* lit =
+        new (zone_) Literal(zone_, ast_value_factory_->NewSmi(number), pos);
+    VISIT_AND_RETURN(Literal, lit)
+  }
+
+  Literal* NewBooleanLiteral(bool b, int pos) {
+    Literal* lit =
+        new (zone_) Literal(zone_, ast_value_factory_->NewBoolean(b), pos);
+    VISIT_AND_RETURN(Literal, lit)
+  }
+
+  Literal* NewStringListLiteral(ZoneList<const AstString*>* strings, int pos) {
+    Literal* lit = new (zone_)
+        Literal(zone_, ast_value_factory_->NewStringList(strings), pos);
+    VISIT_AND_RETURN(Literal, lit)
+  }
+
+  Literal* NewNullLiteral(int pos) {
+    Literal* lit =
+        new (zone_) Literal(zone_, ast_value_factory_->NewNull(), pos);
+    VISIT_AND_RETURN(Literal, lit)
+  }
+
+  Literal* NewUndefinedLiteral(int pos) {
+    Literal* lit =
+        new (zone_) Literal(zone_, ast_value_factory_->NewUndefined(), pos);
+    VISIT_AND_RETURN(Literal, lit)
+  }
+
+  Literal* NewTheHoleLiteral(int pos) {
+    Literal* lit =
+        new (zone_) Literal(zone_, ast_value_factory_->NewTheHole(), pos);
+    VISIT_AND_RETURN(Literal, lit)
   }
 
   ObjectLiteral* NewObjectLiteral(
       ZoneList<ObjectLiteral::Property*>* properties,
       int literal_index,
       int boilerplate_properties,
       bool has_function,
       int pos) {
     ObjectLiteral* lit = new(zone_) ObjectLiteral(
         zone_, properties, literal_index, boilerplate_properties,
         has_function, pos);
     VISIT_AND_RETURN(ObjectLiteral, lit)
   }
 
   ObjectLiteral::Property* NewObjectLiteralProperty(Literal* key,
                                                     Expression* value) {
-    return new(zone_) ObjectLiteral::Property(zone_, key, value);
+    return new (zone_)
+        ObjectLiteral::Property(zone_, ast_value_factory_, key, value);
   }
 
   ObjectLiteral::Property* NewObjectLiteralProperty(bool is_getter,
                                                     FunctionLiteral* value,
                                                     int pos) {
     ObjectLiteral::Property* prop =
         new(zone_) ObjectLiteral::Property(zone_, is_getter, value);
-    prop->set_key(NewLiteral(value->name(), pos));
+    prop->set_key(NewStringLiteral(value->raw_name(), pos));
     return prop;  // Not an AST node, will not be visited.
   }
 
-  RegExpLiteral* NewRegExpLiteral(Handle<String> pattern,
-                                  Handle<String> flags,
+  RegExpLiteral* NewRegExpLiteral(const AstString* pattern,
+                                  const AstString* flags,
                                   int literal_index,
                                   int pos) {
     RegExpLiteral* lit =
         new(zone_) RegExpLiteral(zone_, pattern, flags, literal_index, pos);
     VISIT_AND_RETURN(RegExpLiteral, lit);
   }
 
   ArrayLiteral* NewArrayLiteral(ZoneList<Expression*>* values,
                                 int literal_index,
                                 int pos) {
     ArrayLiteral* lit = new(zone_) ArrayLiteral(
         zone_, values, literal_index, pos);
     VISIT_AND_RETURN(ArrayLiteral, lit)
   }
 
   VariableProxy* NewVariableProxy(Variable* var,
                                   int pos = RelocInfo::kNoPosition) {
     VariableProxy* proxy = new(zone_) VariableProxy(zone_, var, pos);
     VISIT_AND_RETURN(VariableProxy, proxy)
   }
 
-  VariableProxy* NewVariableProxy(Handle<String> name,
+  VariableProxy* NewVariableProxy(const AstString* name,
                                   bool is_this,
                                   Interface* interface = Interface::NewValue(),
                                   int position = RelocInfo::kNoPosition) {
     VariableProxy* proxy =
         new(zone_) VariableProxy(zone_, name, is_this, interface, position);
     VISIT_AND_RETURN(VariableProxy, proxy)
   }
 
   Property* NewProperty(Expression* obj, Expression* key, int pos) {
     Property* prop = new(zone_) Property(zone_, obj, key, pos);
     VISIT_AND_RETURN(Property, prop)
   }
 
   Call* NewCall(Expression* expression,
                 ZoneList<Expression*>* arguments,
                 int pos) {
     Call* call = new(zone_) Call(zone_, expression, arguments, pos);
     VISIT_AND_RETURN(Call, call)
   }
 
   CallNew* NewCallNew(Expression* expression,
                       ZoneList<Expression*>* arguments,
                       int pos) {
     CallNew* call = new(zone_) CallNew(zone_, expression, arguments, pos);
     VISIT_AND_RETURN(CallNew, call)
   }
 
-  CallRuntime* NewCallRuntime(Handle<String> name,
+  CallRuntime* NewCallRuntime(const AstString* name,
                               const Runtime::Function* function,
                               ZoneList<Expression*>* arguments,
                               int pos) {
     CallRuntime* call =
         new(zone_) CallRuntime(zone_, name, function, arguments, pos);
     VISIT_AND_RETURN(CallRuntime, call)
   }
 
   UnaryOperation* NewUnaryOperation(Token::Value op,
                                     Expression* expression,
@@ skipping 57 matching lines @@
         zone_, generator_object, expression, yield_kind, pos);
     VISIT_AND_RETURN(Yield, yield)
   }
 
   Throw* NewThrow(Expression* exception, int pos) {
     Throw* t = new(zone_) Throw(zone_, exception, pos);
     VISIT_AND_RETURN(Throw, t)
   }
 
   FunctionLiteral* NewFunctionLiteral(
-      Handle<String> name,
+      const AstString* name,
+      AstValueFactory* ast_value_factory,
       Scope* scope,
       ZoneList<Statement*>* body,
       int materialized_literal_count,
       int expected_property_count,
       int handler_count,
       int parameter_count,
       FunctionLiteral::ParameterFlag has_duplicate_parameters,
       FunctionLiteral::FunctionType function_type,
       FunctionLiteral::IsFunctionFlag is_function,
       FunctionLiteral::IsParenthesizedFlag is_parenthesized,
       FunctionLiteral::IsGeneratorFlag is_generator,
       int position) {
     FunctionLiteral* lit = new(zone_) FunctionLiteral(
-        zone_, name, scope, body,
+        zone_, name, ast_value_factory, scope, body,
         materialized_literal_count, expected_property_count, handler_count,
         parameter_count, function_type, has_duplicate_parameters, is_function,
         is_parenthesized, is_generator, position);
     // Top-level literal doesn't count for the AST's properties.
     if (is_function == FunctionLiteral::kIsFunction) {
       visitor_.VisitFunctionLiteral(lit);
     }
     return lit;
   }
 
   NativeFunctionLiteral* NewNativeFunctionLiteral(
-      Handle<String> name, v8::Extension* extension, int pos) {
+      const AstString* name, v8::Extension* extension,
+      int pos) {
     NativeFunctionLiteral* lit =
         new(zone_) NativeFunctionLiteral(zone_, name, extension, pos);
     VISIT_AND_RETURN(NativeFunctionLiteral, lit)
   }
 
   ThisFunction* NewThisFunction(int pos) {
     ThisFunction* fun = new(zone_) ThisFunction(zone_, pos);
     VISIT_AND_RETURN(ThisFunction, fun)
   }
 
 #undef VISIT_AND_RETURN
 
  private:
   Zone* zone_;
   Visitor visitor_;
+  AstValueFactory* ast_value_factory_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_AST_H_