AST nodes have at most one bailout/typefeedback ID now, saving lots of memory.

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"
@@ skipping 168 matching lines @@
 };
 
 
 class AstNode: public ZoneObject {
  public:
   // For generating IDs for AstNodes.
   class IdGen {
    public:
     IdGen() : id_(BailoutId::FirstUsable().ToInt()) {}
 
-    int GetNextId() { return ReserveIdRange(1); }
     int ReserveIdRange(int n) {
       int tmp = id_;
       id_ += n;
       return tmp;
     }
 
    private:
     int id_;
 
     DISALLOW_COPY_AND_ASSIGN(IdGen);
@@ skipping 38 matching lines @@
   // node types which don't actually have this. Note that this is conceptually
   // not really nice, but multiple inheritance would introduce yet another
   // vtable entry per node, something we don't want for space reasons.
   static const int kInvalidFeedbackSlot = -1;
   virtual int ComputeFeedbackSlotCount() {
     UNREACHABLE();
     return 0;
   }
   virtual void SetFirstFeedbackSlot(int slot) { UNREACHABLE(); }
 
- protected:
-  // Some nodes re-use bailout IDs for type feedback.
-  static TypeFeedbackId reuse(BailoutId id) {
-    return TypeFeedbackId(id.ToInt());
-  }
-
-
  private:
   // Hidden to prevent accidental usage. It would have to load the
   // current zone from the TLS.
   void* operator new(size_t size);
 
   friend class CaseClause;  // Generates AST IDs.
 
   int position_;
 };
 
@@ skipping 118 matching lines @@
   }
   virtual KeyedAccessStoreMode GetStoreMode() {
     UNREACHABLE();
     return STANDARD_STORE;
   }
 
   // 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_; }
+  BailoutId id() const { return BailoutId(base_id() + 0); }
+  TypeFeedbackId test_id() const { return TypeFeedbackId(base_id() + 1); }
 
  protected:
-  Expression(Zone* zone, int pos, IdGen* id_gen)
+  Expression(Zone* zone, int pos, int num_ids_needed_by_subclass, IdGen* id_gen)
       : AstNode(pos),
         is_parenthesized_(false),
         is_multi_parenthesized_(false),
         bounds_(Bounds::Unbounded(zone)),
-        id_(id_gen->GetNextId()),
-        test_id_(id_gen->GetNextId()) {}
+        base_id_(
+            id_gen->ReserveIdRange(num_ids_needed_by_subclass + num_ids())) {}
   void set_to_boolean_types(byte types) { to_boolean_types_ = types; }
 
+  static int num_ids() { return 2; }
+  int base_id() const { return base_id_; }
+
  private:
   byte to_boolean_types_;
   bool is_parenthesized_ : 1;
   bool is_multi_parenthesized_ : 1;
   Bounds bounds_;
-
-  const BailoutId id_;
-  const TypeFeedbackId test_id_;
+  const int base_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.
   ZoneList<const AstRawString*>* labels() const { return labels_; }
 
   // Type testing & conversion.
   virtual BreakableStatement* AsBreakableStatement() FINAL 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_; }
+  BailoutId EntryId() const { return BailoutId(base_id() + 0); }
+  BailoutId ExitId() const { return BailoutId(base_id() + 1); }
 
  protected:
   BreakableStatement(Zone* zone, ZoneList<const AstRawString*>* labels,
-                     BreakableType breakable_type, int position, IdGen* id_gen)
+                     BreakableType breakable_type, int position,
+                     int num_ids_needed_by_subclass, IdGen* id_gen)
       : Statement(zone, position),
         labels_(labels),
         breakable_type_(breakable_type),
-        entry_id_(id_gen->GetNextId()),
-        exit_id_(id_gen->GetNextId()) {
+        base_id_(
+            id_gen->ReserveIdRange(num_ids_needed_by_subclass + num_ids())) {
     DCHECK(labels == NULL || labels->length() > 0);
   }
 
+  static int num_ids() { return 2; }
+  int base_id() const { return base_id_; }
 
  private:
   ZoneList<const AstRawString*>* labels_;
   BreakableType breakable_type_;
   Label break_target_;
-  const BailoutId entry_id_;
-  const BailoutId exit_id_;
+  const int base_id_;
 };
 
 
 class Block FINAL : public BreakableStatement {
  public:
   DECLARE_NODE_TYPE(Block)
 
   void AddStatement(Statement* statement, Zone* zone) {
     statements_.Add(statement, zone);
   }
 
   ZoneList<Statement*>* statements() { return &statements_; }
   bool is_initializer_block() const { return is_initializer_block_; }
 
-  BailoutId DeclsId() const { return decls_id_; }
+  BailoutId DeclsId() const { return BailoutId(base_id() + 0); }
 
   virtual bool IsJump() const 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, ZoneList<const AstRawString*>* labels, int capacity,
         bool is_initializer_block, int pos, IdGen* id_gen)
-      : BreakableStatement(zone, labels, TARGET_FOR_NAMED_ONLY, pos, id_gen),
+      : BreakableStatement(zone, labels, TARGET_FOR_NAMED_ONLY, pos, num_ids(),
+                           id_gen),
         statements_(capacity, zone),
         is_initializer_block_(is_initializer_block),
-        decls_id_(id_gen->GetNextId()),
         scope_(NULL) {}
 
+  static int num_ids() { return 1; }
+  int base_id() const {
+    return BreakableStatement::base_id() + BreakableStatement::num_ids();
+  }
+
  private:
   ZoneList<Statement*> statements_;
   bool is_initializer_block_;
-  const BailoutId decls_id_;
   Scope* scope_;
 };
 
 
 class Declaration : public AstNode {
  public:
   VariableProxy* proxy() const { return proxy_; }
   VariableMode mode() const { return mode_; }
   Scope* scope() const { return scope_; }
   virtual InitializationFlag initialization() const = 0;
@@ skipping 231 matching lines @@
 
 class IterationStatement : public BreakableStatement {
  public:
   // Type testing & conversion.
   virtual IterationStatement* AsIterationStatement() FINAL OVERRIDE {
     return this;
   }
 
   Statement* body() const { return body_; }
 
-  BailoutId OsrEntryId() const { return osr_entry_id_; }
+  BailoutId OsrEntryId() const { return BailoutId(base_id() + 0); }
   virtual BailoutId ContinueId() const = 0;
   virtual BailoutId StackCheckId() const = 0;
 
   // Code generation
   Label* continue_target()  { return &continue_target_; }
 
  protected:
   IterationStatement(Zone* zone, ZoneList<const AstRawString*>* labels, int pos,
-                     IdGen* id_gen)
-      : BreakableStatement(zone, labels, TARGET_FOR_ANONYMOUS, pos, id_gen),
-        body_(NULL),
-        osr_entry_id_(id_gen->GetNextId()) {}
+                     int num_ids_needed_by_subclass, IdGen* id_gen)
+      : BreakableStatement(zone, labels, TARGET_FOR_ANONYMOUS, pos,
+                           num_ids_needed_by_subclass + num_ids(), id_gen),
+        body_(NULL) {}
 
   void Initialize(Statement* body) {
     body_ = body;
   }
 
+  static int num_ids() { return 1; }
+  int base_id() const {
+    return BreakableStatement::base_id() + BreakableStatement::num_ids();
+  }
+
  private:
   Statement* body_;
   Label continue_target_;
-
-  const BailoutId osr_entry_id_;
 };
 
 
 class DoWhileStatement FINAL : public IterationStatement {
  public:
   DECLARE_NODE_TYPE(DoWhileStatement)
 
   void Initialize(Expression* cond, Statement* body) {
     IterationStatement::Initialize(body);
     cond_ = cond;
   }
 
   Expression* cond() const { return cond_; }
 
-  virtual BailoutId ContinueId() const OVERRIDE { return continue_id_; }
-  virtual BailoutId StackCheckId() const OVERRIDE { return back_edge_id_; }
-  BailoutId BackEdgeId() const { return back_edge_id_; }
+  virtual BailoutId ContinueId() const OVERRIDE {
+    return BailoutId(base_id() + 0);
+  }
+  virtual BailoutId StackCheckId() const OVERRIDE { return BackEdgeId(); }
+  BailoutId BackEdgeId() const { return BailoutId(base_id() + 1); }
 
  protected:
   DoWhileStatement(Zone* zone, ZoneList<const AstRawString*>* labels, int pos,
                    IdGen* id_gen)
-      : IterationStatement(zone, labels, pos, id_gen),
-        cond_(NULL),
-        continue_id_(id_gen->GetNextId()),
-        back_edge_id_(id_gen->GetNextId()) {}
+      : IterationStatement(zone, labels, pos, num_ids(), id_gen), cond_(NULL) {}
+
+  static int num_ids() { return 2; }
+  int base_id() const {
+    return IterationStatement::base_id() + IterationStatement::num_ids();
+  }
 
  private:
   Expression* cond_;
-
-  const BailoutId continue_id_;
-  const BailoutId back_edge_id_;
 };
 
 
 class WhileStatement FINAL : public IterationStatement {
  public:
   DECLARE_NODE_TYPE(WhileStatement)
 
   void Initialize(Expression* cond, Statement* body) {
     IterationStatement::Initialize(body);
     cond_ = cond;
   }
 
   Expression* cond() const { return cond_; }
   bool may_have_function_literal() const {
     return may_have_function_literal_;
   }
   void set_may_have_function_literal(bool value) {
     may_have_function_literal_ = value;
   }
 
   virtual BailoutId ContinueId() const OVERRIDE { return EntryId(); }
-  virtual BailoutId StackCheckId() const OVERRIDE { return body_id_; }
-  BailoutId BodyId() const { return body_id_; }
+  virtual BailoutId StackCheckId() const OVERRIDE { return BodyId(); }
+  BailoutId BodyId() const { return BailoutId(base_id() + 0); }
 
  protected:
   WhileStatement(Zone* zone, ZoneList<const AstRawString*>* labels, int pos,
                  IdGen* id_gen)
-      : IterationStatement(zone, labels, pos, id_gen),
+      : IterationStatement(zone, labels, pos, num_ids(), id_gen),
         cond_(NULL),
-        may_have_function_literal_(true),
-        body_id_(id_gen->GetNextId()) {}
+        may_have_function_literal_(true) {}
+
+  static int num_ids() { return 1; }
+  int base_id() const {
+    return IterationStatement::base_id() + IterationStatement::num_ids();
+  }
 
  private:
   Expression* cond_;
 
   // True if there is a function literal subexpression in the condition.
   bool may_have_function_literal_;
-
-  const BailoutId body_id_;
 };
 
 
 class ForStatement FINAL : public IterationStatement {
  public:
   DECLARE_NODE_TYPE(ForStatement)
 
   void Initialize(Statement* init,
                   Expression* cond,
                   Statement* next,
                   Statement* body) {
     IterationStatement::Initialize(body);
     init_ = init;
     cond_ = cond;
     next_ = next;
   }
 
   Statement* init() const { return init_; }
   Expression* cond() const { return cond_; }
   Statement* next() const { return next_; }
 
   bool may_have_function_literal() const {
     return may_have_function_literal_;
   }
   void set_may_have_function_literal(bool value) {
     may_have_function_literal_ = value;
   }
 
-  virtual BailoutId ContinueId() const OVERRIDE { return continue_id_; }
-  virtual BailoutId StackCheckId() const OVERRIDE { return body_id_; }
-  BailoutId BodyId() const { return body_id_; }
+  virtual BailoutId ContinueId() const OVERRIDE {
+    return BailoutId(base_id() + 0);
+  }
+  virtual BailoutId StackCheckId() const OVERRIDE { return BodyId(); }
+  BailoutId BodyId() const { return BailoutId(base_id() + 1); }
 
   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, ZoneList<const AstRawString*>* labels, int pos,
                IdGen* id_gen)
-      : IterationStatement(zone, labels, pos, id_gen),
+      : IterationStatement(zone, labels, pos, num_ids(), id_gen),
         init_(NULL),
         cond_(NULL),
         next_(NULL),
         may_have_function_literal_(true),
-        loop_variable_(NULL),
-        continue_id_(id_gen->GetNextId()),
-        body_id_(id_gen->GetNextId()) {}
+        loop_variable_(NULL) {}
+
+  static int num_ids() { return 2; }
+  int base_id() const {
+    return IterationStatement::base_id() + IterationStatement::num_ids();
+  }
 
  private:
   Statement* init_;
   Expression* cond_;
   Statement* next_;
 
   // True if there is a function literal subexpression in the condition.
   bool may_have_function_literal_;
   Variable* loop_variable_;
-
-  const BailoutId continue_id_;
-  const BailoutId body_id_;
 };
 
 
 class ForEachStatement : public IterationStatement {
  public:
   enum VisitMode {
     ENUMERATE,   // for (each in subject) body;
     ITERATE      // for (each of subject) body;
   };
 
   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, ZoneList<const AstRawString*>* labels, int pos,
-                   IdGen* id_gen)
-      : IterationStatement(zone, labels, pos, id_gen),
+                   int num_ids_needed_by_subclass, IdGen* id_gen)
+      : IterationStatement(zone, labels, pos, num_ids_needed_by_subclass,
+                           id_gen),
         each_(NULL),
         subject_(NULL) {}
 
  private:
   Expression* each_;
   Expression* subject_;
 };
 
 
 class ForInStatement FINAL : public ForEachStatement {
@@ skipping 10 matching lines @@
 
   int ForInFeedbackSlot() {
     DCHECK(for_in_feedback_slot_ != kInvalidFeedbackSlot);
     return for_in_feedback_slot_;
   }
 
   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_; }
+  BailoutId BodyId() const { return BailoutId(base_id() + 0); }
+  BailoutId PrepareId() const { return BailoutId(base_id() + 1); }
   virtual BailoutId ContinueId() const OVERRIDE { return EntryId(); }
-  virtual BailoutId StackCheckId() const OVERRIDE { return body_id_; }
+  virtual BailoutId StackCheckId() const OVERRIDE { return BodyId(); }
 
  protected:
   ForInStatement(Zone* zone, ZoneList<const AstRawString*>* labels, int pos,
                  IdGen* id_gen)
-      : ForEachStatement(zone, labels, pos, id_gen),
+      : ForEachStatement(zone, labels, pos, num_ids(), id_gen),
         for_in_type_(SLOW_FOR_IN),
-        for_in_feedback_slot_(kInvalidFeedbackSlot),
-        body_id_(id_gen->GetNextId()),
-        prepare_id_(id_gen->GetNextId()) {}
+        for_in_feedback_slot_(kInvalidFeedbackSlot) {}
 
+  static int num_ids() { return 2; }
+  int base_id() const {
+    return ForEachStatement::base_id() + ForEachStatement::num_ids();
+  }
+
+ private:
   ForInType for_in_type_;
   int for_in_feedback_slot_;
-  const BailoutId body_id_;
-  const BailoutId prepare_id_;
 };
 
 
 class ForOfStatement FINAL : public ForEachStatement {
  public:
   DECLARE_NODE_TYPE(ForOfStatement)
 
   void Initialize(Expression* each,
                   Expression* subject,
                   Statement* body,
@@ skipping 28 matching lines @@
   }
 
   // each = result.value
   Expression* assign_each() const {
     return assign_each_;
   }
 
   virtual BailoutId ContinueId() const OVERRIDE { return EntryId(); }
   virtual BailoutId StackCheckId() const OVERRIDE { return BackEdgeId(); }
 
-  BailoutId BackEdgeId() const { return back_edge_id_; }
+  BailoutId BackEdgeId() const { return BailoutId(base_id() + 0); }
 
  protected:
   ForOfStatement(Zone* zone, ZoneList<const AstRawString*>* labels, int pos,
                  IdGen* id_gen)
-      : ForEachStatement(zone, labels, pos, id_gen),
+      : ForEachStatement(zone, labels, pos, num_ids(), id_gen),
         assign_iterator_(NULL),
         next_result_(NULL),
         result_done_(NULL),
-        assign_each_(NULL),
-        back_edge_id_(id_gen->GetNextId()) {}
+        assign_each_(NULL) {}
 
+  static int num_ids() { return 1; }
+  int base_id() const {
+    return ForEachStatement::base_id() + ForEachStatement::num_ids();
+  }
+
+ private:
   Expression* assign_iterator_;
   Expression* next_result_;
   Expression* result_done_;
   Expression* assign_each_;
-  const BailoutId back_edge_id_;
 };
 
 
 class ExpressionStatement FINAL : public Statement {
  public:
   DECLARE_NODE_TYPE(ExpressionStatement)
 
   void set_expression(Expression* e) { expression_ = e; }
   Expression* expression() const { return expression_; }
   virtual bool IsJump() const OVERRIDE { return expression_->IsThrow(); }
@@ skipping 90 matching lines @@
   DECLARE_NODE_TYPE(CaseClause)
 
   bool is_default() const { return label_ == NULL; }
   Expression* label() const {
     CHECK(!is_default());
     return label_;
   }
   Label* body_target() { return &body_target_; }
   ZoneList<Statement*>* statements() const { return statements_; }
 
-  BailoutId EntryId() const { return entry_id_; }
+  BailoutId EntryId() const { return BailoutId(base_id() + 0); }
+  TypeFeedbackId CompareId() { return TypeFeedbackId(base_id() + 1); }
 
-  // Type feedback information.
-  TypeFeedbackId CompareId() { return compare_id_; }
   Type* compare_type() { return compare_type_; }
   void set_compare_type(Type* type) { compare_type_ = type; }
 
  private:
   CaseClause(Zone* zone, Expression* label, ZoneList<Statement*>* statements,
              int pos, IdGen* id_gen);
 
+  static int num_ids() { return 2; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
+
   Expression* label_;
   Label body_target_;
   ZoneList<Statement*>* statements_;
   Type* compare_type_;
-
-  const TypeFeedbackId compare_id_;
-  const BailoutId entry_id_;
 };
 
 
 class SwitchStatement FINAL : public BreakableStatement {
  public:
   DECLARE_NODE_TYPE(SwitchStatement)
 
   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, ZoneList<const AstRawString*>* labels, int pos,
                   IdGen* id_gen)
-      : BreakableStatement(zone, labels, TARGET_FOR_ANONYMOUS, pos, id_gen),
+      : BreakableStatement(zone, labels, TARGET_FOR_ANONYMOUS, pos, 0, id_gen),
         tag_(NULL),
         cases_(NULL) {}
 
  private:
   Expression* tag_;
   ZoneList<CaseClause*>* cases_;
 };
 
 
 // If-statements always have non-null references to their then- and
@@ skipping 10 matching lines @@
 
   Expression* condition() const { return condition_; }
   Statement* then_statement() const { return then_statement_; }
   Statement* else_statement() const { return else_statement_; }
 
   virtual bool IsJump() const OVERRIDE {
     return HasThenStatement() && then_statement()->IsJump()
         && HasElseStatement() && else_statement()->IsJump();
   }
 
-  BailoutId IfId() const { return if_id_; }
-  BailoutId ThenId() const { return then_id_; }
-  BailoutId ElseId() const { return else_id_; }
+  BailoutId IfId() const { return BailoutId(base_id() + 0); }
+  BailoutId ThenId() const { return BailoutId(base_id() + 1); }
+  BailoutId ElseId() const { return BailoutId(base_id() + 2); }
 
  protected:
   IfStatement(Zone* zone, Expression* condition, Statement* then_statement,
               Statement* else_statement, int pos, IdGen* id_gen)
       : Statement(zone, pos),
         condition_(condition),
         then_statement_(then_statement),
         else_statement_(else_statement),
-        if_id_(id_gen->GetNextId()),
-        then_id_(id_gen->GetNextId()),
-        else_id_(id_gen->GetNextId()) {}
+        base_id_(id_gen->ReserveIdRange(num_ids())) {}
+
+  static int num_ids() { return 3; }
+  int base_id() const { return base_id_; }
 
  private:
   Expression* condition_;
   Statement* then_statement_;
   Statement* else_statement_;
-  const BailoutId if_id_;
-  const BailoutId then_id_;
-  const BailoutId else_id_;
+  const int base_id_;
 };
 
 
 // NOTE: TargetCollectors are represented as nodes to fit in the target
 // stack in the compiler; this should probably be reworked.
 class TargetCollector FINAL : public AstNode {
  public:
   explicit TargetCollector(Zone* zone)
       : AstNode(RelocInfo::kNoPosition), targets_(0, zone) { }
 
@@ skipping 83 matching lines @@
 
  private:
   Block* finally_block_;
 };
 
 
 class DebuggerStatement FINAL : public Statement {
  public:
   DECLARE_NODE_TYPE(DebuggerStatement)
 
-  BailoutId DebugBreakId() const { return debugger_id_; }
+  BailoutId DebugBreakId() const { return BailoutId(base_id() + 0); }
 
  protected:
   explicit DebuggerStatement(Zone* zone, int pos, IdGen* id_gen)
-      : Statement(zone, pos), debugger_id_(id_gen->GetNextId()) {}
+      : Statement(zone, pos), base_id_(id_gen->ReserveIdRange(num_ids())) {}
+
+  static int num_ids() { return 1; }
+  int base_id() const { return base_id_; }
 
  private:
-  const BailoutId debugger_id_;
+  const int base_id_;
 };
 
 
 class EmptyStatement FINAL : public Statement {
  public:
   DECLARE_NODE_TYPE(EmptyStatement)
 
  protected:
   explicit EmptyStatement(Zone* zone, int pos): Statement(zone, pos) {}
 };
@@ skipping 25 matching lines @@
   }
 
   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();
   static bool Match(void* literal1, void* literal2);
 
-  TypeFeedbackId LiteralFeedbackId() const { return reuse(id()); }
+  TypeFeedbackId LiteralFeedbackId() const {
+    return TypeFeedbackId(base_id() + 0);
+  }
 
  protected:
   Literal(Zone* zone, const AstValue* value, int position, IdGen* id_gen)
-      : Expression(zone, position, id_gen), value_(value) {}
+      : Expression(zone, position, num_ids(), id_gen), value_(value) {}
+
+  static int num_ids() { return 1; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
 
  private:
   const AstValue* value_;
 };
 
 
 // Base class for literals that needs space in the corresponding JSFunction.
 class MaterializedLiteral : public Expression {
  public:
   virtual MaterializedLiteral* AsMaterializedLiteral() { return this; }
 
   int literal_index() { return literal_index_; }
 
   int depth() const {
     // only callable after initialization.
     DCHECK(depth_ >= 1);
     return depth_;
   }
 
  protected:
-  MaterializedLiteral(Zone* zone, int literal_index, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+  MaterializedLiteral(Zone* zone, int literal_index, int pos,
+                      int num_ids_needed_by_subclass, IdGen* id_gen)
+      : Expression(zone, pos, num_ids_needed_by_subclass, id_gen),
         literal_index_(literal_index),
         is_simple_(false),
         depth_(0) {}
 
   // A materialized literal is simple if the values consist of only
   // constants and simple object and array literals.
   bool is_simple() const { return is_simple_; }
   void set_is_simple(bool is_simple) { is_simple_ = is_simple; }
   friend class CompileTimeValue;
 
@@ skipping 111 matching lines @@
   struct Accessors: public ZoneObject {
     Accessors() : getter(NULL), setter(NULL) { }
     Expression* getter;
     Expression* setter;
   };
 
  protected:
   ObjectLiteral(Zone* zone, ZoneList<Property*>* properties, int literal_index,
                 int boilerplate_properties, bool has_function, int pos,
                 IdGen* id_gen)
-      : MaterializedLiteral(zone, literal_index, pos, id_gen),
+      : MaterializedLiteral(zone, literal_index, pos, 0, id_gen),
         properties_(properties),
         boilerplate_properties_(boilerplate_properties),
         fast_elements_(false),
         may_store_doubles_(false),
         has_function_(has_function) {}
 
  private:
   Handle<FixedArray> constant_properties_;
   ZoneList<Property*>* properties_;
   int boilerplate_properties_;
   bool fast_elements_;
   bool may_store_doubles_;
   bool has_function_;
 };
 
 
 // Node for capturing a regexp literal.
 class RegExpLiteral FINAL : public MaterializedLiteral {
  public:
   DECLARE_NODE_TYPE(RegExpLiteral)
 
   Handle<String> pattern() const { return pattern_->string(); }
   Handle<String> flags() const { return flags_->string(); }
 
  protected:
   RegExpLiteral(Zone* zone, const AstRawString* pattern,
                 const AstRawString* flags, int literal_index, int pos,
                 IdGen* id_gen)
-      : MaterializedLiteral(zone, literal_index, pos, id_gen),
+      : MaterializedLiteral(zone, literal_index, pos, 0, id_gen),
         pattern_(pattern),
         flags_(flags) {
     set_depth(1);
   }
 
  private:
   const AstRawString* pattern_;
   const AstRawString* flags_;
 };
 
 
 // An array literal has a literals object that is used
 // for minimizing the work when constructing it at runtime.
 class ArrayLiteral FINAL : public MaterializedLiteral {
  public:
   DECLARE_NODE_TYPE(ArrayLiteral)
 
   Handle<FixedArray> constant_elements() const { return constant_elements_; }
   ZoneList<Expression*>* values() const { return values_; }
 
   // Return an AST id for an element that is used in simulate instructions.
-  BailoutId GetIdForElement(int i) {
-    return BailoutId(first_element_id_.ToInt() + i);
-  }
+  BailoutId GetIdForElement(int i) { return BailoutId(base_id() + i); }
 
   // Populate the constant elements fixed array.
   void BuildConstantElements(Isolate* isolate);
 
   // Assemble bitfield of flags for the CreateArrayLiteral helper.
   int ComputeFlags() const {
     int flags = depth() == 1 ? kShallowElements : kNoFlags;
     flags |= ArrayLiteral::kDisableMementos;
     return flags;
   }
 
   enum Flags {
     kNoFlags = 0,
     kShallowElements = 1,
     kDisableMementos = 1 << 1
   };
 
  protected:
   ArrayLiteral(Zone* zone, ZoneList<Expression*>* values, int literal_index,
                int pos, IdGen* id_gen)
-      : MaterializedLiteral(zone, literal_index, pos, id_gen),
-        values_(values),
-        first_element_id_(id_gen->ReserveIdRange(values->length())) {}
+      : MaterializedLiteral(zone, literal_index, pos, num_ids(values), id_gen),
+        values_(values) {}
+
+  static int num_ids(ZoneList<Expression*>* values) { return values->length(); }
+  int base_id() const {
+    return MaterializedLiteral::base_id() + MaterializedLiteral::num_ids();
+  }
 
  private:
   Handle<FixedArray> constant_elements_;
   ZoneList<Expression*>* values_;
-  const BailoutId first_element_id_;
 };
 
 
 class VariableProxy FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(VariableProxy)
 
   virtual bool IsValidReferenceExpression() const OVERRIDE {
     return !is_resolved() || var()->IsValidReference();
   }
@@ skipping 55 matching lines @@
 
 class Property FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(Property)
 
   virtual bool IsValidReferenceExpression() const OVERRIDE { return true; }
 
   Expression* obj() const { return obj_; }
   Expression* key() const { return key_; }
 
-  BailoutId LoadId() const { return load_id_; }
+  BailoutId LoadId() const { return BailoutId(base_id() + 0); }
+  TypeFeedbackId PropertyFeedbackId() { return TypeFeedbackId(base_id() + 1); }
+
 
   bool IsStringAccess() const { return is_string_access_; }
 
   // Type feedback information.
   virtual bool IsMonomorphic() OVERRIDE {
     return receiver_types_.length() == 1;
   }
   virtual SmallMapList* GetReceiverTypes() OVERRIDE {
     return &receiver_types_;
   }
   virtual KeyedAccessStoreMode GetStoreMode() OVERRIDE {
     return STANDARD_STORE;
   }
   bool IsUninitialized() { return !is_for_call_ && is_uninitialized_; }
   bool HasNoTypeInformation() {
     return is_uninitialized_;
   }
   void set_is_uninitialized(bool b) { is_uninitialized_ = b; }
   void set_is_string_access(bool b) { is_string_access_ = b; }
   void mark_for_call() { is_for_call_ = true; }
   bool IsForCall() { return is_for_call_; }
 
   bool IsSuperAccess() {
     return obj()->IsSuperReference();
   }
 
-  TypeFeedbackId PropertyFeedbackId() { return reuse(id()); }
-
   virtual int ComputeFeedbackSlotCount() { return FLAG_vector_ics ? 1 : 0; }
   virtual void SetFirstFeedbackSlot(int slot) {
     property_feedback_slot_ = slot;
   }
 
   int PropertyFeedbackSlot() const { return property_feedback_slot_; }
 
  protected:
   Property(Zone* zone, Expression* obj, Expression* key, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, num_ids(), id_gen),
         obj_(obj),
         key_(key),
-        load_id_(id_gen->GetNextId()),
         property_feedback_slot_(kInvalidFeedbackSlot),
         is_for_call_(false),
         is_uninitialized_(false),
         is_string_access_(false) {}
 
+  static int num_ids() { return 2; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
+
  private:
   Expression* obj_;
   Expression* key_;
-  const BailoutId load_id_;
   int property_feedback_slot_;
 
   SmallMapList receiver_types_;
   bool is_for_call_ : 1;
   bool is_uninitialized_ : 1;
   bool is_string_access_ : 1;
 };
 
 
 class Call FINAL : public Expression {
@@ skipping 42 matching lines @@
   Handle<Cell> cell() { return cell_; }
 
   Handle<AllocationSite> allocation_site() { return allocation_site_; }
 
   void set_target(Handle<JSFunction> target) { target_ = target; }
   void set_allocation_site(Handle<AllocationSite> site) {
     allocation_site_ = site;
   }
   bool ComputeGlobalTarget(Handle<GlobalObject> global, LookupIterator* it);
 
-  BailoutId ReturnId() const { return return_id_; }
-  BailoutId EvalOrLookupId() const { return eval_or_lookup_id_; }
+  BailoutId ReturnId() const { return BailoutId(base_id() + 0); }
+  BailoutId EvalOrLookupId() const { return BailoutId(base_id() + 1); }
 
   enum CallType {
     POSSIBLY_EVAL_CALL,
     GLOBAL_CALL,
     LOOKUP_SLOT_CALL,
     PROPERTY_CALL,
     OTHER_CALL
   };
 
   // Helpers to determine how to handle the call.
   CallType GetCallType(Isolate* isolate) const;
   bool IsUsingCallFeedbackSlot(Isolate* isolate) const;
 
 #ifdef DEBUG
   // Used to assert that the FullCodeGenerator records the return site.
   bool return_is_recorded_;
 #endif
 
  protected:
   Call(Zone* zone, Expression* expression, ZoneList<Expression*>* arguments,
        int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, num_ids(), id_gen),
         expression_(expression),
         arguments_(arguments),
-        call_feedback_slot_(kInvalidFeedbackSlot),
-        return_id_(id_gen->GetNextId()),
-        eval_or_lookup_id_(id_gen->GetNextId()) {
+        call_feedback_slot_(kInvalidFeedbackSlot) {
     if (expression->IsProperty()) {
       expression->AsProperty()->mark_for_call();
     }
   }
 
+  static int num_ids() { return 2; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
+
  private:
   Expression* expression_;
   ZoneList<Expression*>* arguments_;
-
   Handle<JSFunction> target_;
   Handle<Cell> cell_;
   Handle<AllocationSite> allocation_site_;
   int call_feedback_slot_;
-
-  const BailoutId return_id_;
-  // TODO(jarin) Only allocate the bailout id for the POSSIBLY_EVAL_CALL and
-  // LOOKUP_SLOT_CALL types.
-  const BailoutId eval_or_lookup_id_;
 };
 
 
 class CallNew FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(CallNew)
 
   Expression* expression() const { return expression_; }
   ZoneList<Expression*>* arguments() const { return arguments_; }
 
@@ skipping 17 matching lines @@
 
   void RecordTypeFeedback(TypeFeedbackOracle* oracle);
   virtual bool IsMonomorphic() OVERRIDE { return is_monomorphic_; }
   Handle<JSFunction> target() const { return target_; }
   Handle<AllocationSite> allocation_site() const {
     return allocation_site_;
   }
 
   static int feedback_slots() { return 1; }
 
-  BailoutId ReturnId() const { return return_id_; }
+  BailoutId ReturnId() const { return BailoutId(base_id() + 0); }
 
  protected:
   CallNew(Zone* zone, Expression* expression, ZoneList<Expression*>* arguments,
           int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, num_ids(), id_gen),
         expression_(expression),
         arguments_(arguments),
         is_monomorphic_(false),
-        callnew_feedback_slot_(kInvalidFeedbackSlot),
-        return_id_(id_gen->GetNextId()) {}
+        callnew_feedback_slot_(kInvalidFeedbackSlot) {}
+
+  static int num_ids() { return 1; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
 
  private:
   Expression* expression_;
   ZoneList<Expression*>* arguments_;
-
   bool is_monomorphic_;
   Handle<JSFunction> target_;
   Handle<AllocationSite> allocation_site_;
   int callnew_feedback_slot_;
-
-  const BailoutId return_id_;
 };
 
 
 // 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 FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(CallRuntime)
@@ skipping 11 matching lines @@
   virtual void SetFirstFeedbackSlot(int slot) {
     callruntime_feedback_slot_ = slot;
   }
 
   int CallRuntimeFeedbackSlot() {
     DCHECK(!is_jsruntime() ||
            callruntime_feedback_slot_ != kInvalidFeedbackSlot);
     return callruntime_feedback_slot_;
   }
 
-  TypeFeedbackId CallRuntimeFeedbackId() const { return reuse(id()); }
+  TypeFeedbackId CallRuntimeFeedbackId() const {
+    return TypeFeedbackId(base_id() + 0);
+  }
 
  protected:
   CallRuntime(Zone* zone, const AstRawString* name,
               const Runtime::Function* function,
               ZoneList<Expression*>* arguments, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, num_ids(), id_gen),
         raw_name_(name),
         function_(function),
         arguments_(arguments) {}
 
+  static int num_ids() { return 1; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
+
  private:
   const AstRawString* raw_name_;
   const Runtime::Function* function_;
   ZoneList<Expression*>* arguments_;
   int callruntime_feedback_slot_;
 };
 
 
 class UnaryOperation FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(UnaryOperation)
 
   Token::Value op() const { return op_; }
   Expression* expression() const { return expression_; }
 
-  BailoutId MaterializeTrueId() { return materialize_true_id_; }
-  BailoutId MaterializeFalseId() { return materialize_false_id_; }
+  // For unary not (Token::NOT), the AST ids where true and false will
+  // actually be materialized, respectively.
+  BailoutId MaterializeTrueId() const { return BailoutId(base_id() + 0); }
+  BailoutId MaterializeFalseId() const { return BailoutId(base_id() + 1); }
 
   virtual void RecordToBooleanTypeFeedback(
       TypeFeedbackOracle* oracle) OVERRIDE;
 
  protected:
   UnaryOperation(Zone* zone, Token::Value op, Expression* expression, int pos,
                  IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, num_ids(), id_gen),
         op_(op),
-        expression_(expression),
-        materialize_true_id_(id_gen->GetNextId()),
-        materialize_false_id_(id_gen->GetNextId()) {
+        expression_(expression) {
     DCHECK(Token::IsUnaryOp(op));
   }
 
+  static int num_ids() { return 2; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
+
  private:
   Token::Value op_;
   Expression* expression_;
-
-  // For unary not (Token::NOT), the AST ids where true and false will
-  // actually be materialized, respectively.
-  const BailoutId materialize_true_id_;
-  const BailoutId materialize_false_id_;
 };
 
 
 class BinaryOperation FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(BinaryOperation)
 
   virtual bool ResultOverwriteAllowed() const OVERRIDE;
 
   Token::Value op() const { return op_; }
   Expression* left() const { return left_; }
   Expression* right() const { return right_; }
   Handle<AllocationSite> allocation_site() const { return allocation_site_; }
   void set_allocation_site(Handle<AllocationSite> allocation_site) {
     allocation_site_ = allocation_site;
   }
 
-  BailoutId RightId() const { return right_id_; }
+  // The short-circuit logical operations need an AST ID for their
+  // right-hand subexpression.
+  BailoutId RightId() const { return BailoutId(base_id() + 0); }
 
-  TypeFeedbackId BinaryOperationFeedbackId() const { return reuse(id()); }
+  TypeFeedbackId BinaryOperationFeedbackId() const {
+    return TypeFeedbackId(base_id() + 1);
+  }
   Maybe<int> fixed_right_arg() const { return fixed_right_arg_; }
   void set_fixed_right_arg(Maybe<int> arg) { fixed_right_arg_ = arg; }
 
   virtual void RecordToBooleanTypeFeedback(
       TypeFeedbackOracle* oracle) OVERRIDE;
 
  protected:
   BinaryOperation(Zone* zone, Token::Value op, Expression* left,
                   Expression* right, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, num_ids(), id_gen),
         op_(op),
         left_(left),
-        right_(right),
-        right_id_(id_gen->GetNextId()) {
+        right_(right) {
     DCHECK(Token::IsBinaryOp(op));
   }
 
+  static int num_ids() { return 2; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
+
  private:
   Token::Value op_;
   Expression* left_;
   Expression* right_;
   Handle<AllocationSite> allocation_site_;
 
   // TODO(rossberg): the fixed arg should probably be represented as a Constant
   // type for the RHS.
   Maybe<int> fixed_right_arg_;
-
-  // The short-circuit logical operations need an AST ID for their
-  // right-hand subexpression.
-  const BailoutId right_id_;
 };
 
 
 class CountOperation FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(CountOperation)
 
   bool is_prefix() const { return is_prefix_; }
   bool is_postfix() const { return !is_prefix_; }
 
@@ skipping 10 matching lines @@
   virtual SmallMapList* GetReceiverTypes() OVERRIDE {
     return &receiver_types_;
   }
   virtual KeyedAccessStoreMode GetStoreMode() OVERRIDE {
     return store_mode_;
   }
   Type* type() const { return type_; }
   void set_store_mode(KeyedAccessStoreMode mode) { store_mode_ = mode; }
   void set_type(Type* type) { type_ = type; }
 
-  BailoutId AssignmentId() const { return assignment_id_; }
-
-  TypeFeedbackId CountBinOpFeedbackId() const { return count_id_; }
-  TypeFeedbackId CountStoreFeedbackId() const { return reuse(id()); }
+  BailoutId AssignmentId() const { return BailoutId(base_id() + 0); }
+  TypeFeedbackId CountBinOpFeedbackId() const {
+    return TypeFeedbackId(base_id() + 1);
+  }
+  TypeFeedbackId CountStoreFeedbackId() const {
+    return TypeFeedbackId(base_id() + 2);
+  }
 
  protected:
   CountOperation(Zone* zone, Token::Value op, bool is_prefix, Expression* expr,
                  int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, num_ids(), id_gen),
         op_(op),
         is_prefix_(is_prefix),
         store_mode_(STANDARD_STORE),
-        expression_(expr),
-        assignment_id_(id_gen->GetNextId()),
-        count_id_(id_gen->GetNextId()) {}
+        expression_(expr) {}
+
+  static int num_ids() { return 3; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
 
  private:
   Token::Value op_;
   bool is_prefix_ : 1;
   KeyedAccessStoreMode store_mode_ : 5;  // Windows treats as signed,
                                          // must have extra bit.
   Type* type_;
-
   Expression* expression_;
-  const BailoutId assignment_id_;
-  const TypeFeedbackId count_id_;
   SmallMapList receiver_types_;
 };
 
 
 class CompareOperation FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(CompareOperation)
 
   Token::Value op() const { return op_; }
   Expression* left() const { return left_; }
   Expression* right() const { return right_; }
 
   // Type feedback information.
-  TypeFeedbackId CompareOperationFeedbackId() const { return reuse(id()); }
+  TypeFeedbackId CompareOperationFeedbackId() const {
+    return TypeFeedbackId(base_id() + 0);
+  }
   Type* combined_type() const { return combined_type_; }
   void set_combined_type(Type* type) { combined_type_ = type; }
 
   // Match special cases.
   bool IsLiteralCompareTypeof(Expression** expr, Handle<String>* check);
   bool IsLiteralCompareUndefined(Expression** expr, Isolate* isolate);
   bool IsLiteralCompareNull(Expression** expr);
 
  protected:
   CompareOperation(Zone* zone, Token::Value op, Expression* left,
                    Expression* right, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, num_ids(), id_gen),
         op_(op),
         left_(left),
         right_(right),
         combined_type_(Type::None(zone)) {
     DCHECK(Token::IsCompareOp(op));
   }
 
+  static int num_ids() { return 1; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
+
  private:
   Token::Value op_;
   Expression* left_;
   Expression* right_;
 
   Type* combined_type_;
 };
 
 
 class Conditional FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(Conditional)
 
   Expression* condition() const { return condition_; }
   Expression* then_expression() const { return then_expression_; }
   Expression* else_expression() const { return else_expression_; }
 
-  BailoutId ThenId() const { return then_id_; }
-  BailoutId ElseId() const { return else_id_; }
+  BailoutId ThenId() const { return BailoutId(base_id() + 0); }
+  BailoutId ElseId() const { return BailoutId(base_id() + 1); }
 
  protected:
   Conditional(Zone* zone, Expression* condition, Expression* then_expression,
               Expression* else_expression, int position, IdGen* id_gen)
-      : Expression(zone, position, id_gen),
+      : Expression(zone, position, num_ids(), id_gen),
         condition_(condition),
         then_expression_(then_expression),
-        else_expression_(else_expression),
-        then_id_(id_gen->GetNextId()),
-        else_id_(id_gen->GetNextId()) {}
+        else_expression_(else_expression) {}
+
+  static int num_ids() { return 2; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
 
  private:
   Expression* condition_;
   Expression* then_expression_;
   Expression* else_expression_;
-  const BailoutId then_id_;
-  const BailoutId else_id_;
 };
 
 
 class Assignment FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(Assignment)
 
   Assignment* AsSimpleAssignment() { return !is_compound() ? this : NULL; }
 
   Token::Value binary_op() const;
 
   Token::Value op() const { return op_; }
   Expression* target() const { return target_; }
   Expression* value() const { return value_; }
   BinaryOperation* binary_operation() const { return binary_operation_; }
 
   // This check relies on the definition order of token in token.h.
   bool is_compound() const { return op() > Token::ASSIGN; }
 
-  BailoutId AssignmentId() const { return assignment_id_; }
+  BailoutId AssignmentId() const { return BailoutId(base_id() + 0); }
 
   // Type feedback information.
-  TypeFeedbackId AssignmentFeedbackId() { return reuse(id()); }
+  TypeFeedbackId AssignmentFeedbackId() {
+    return TypeFeedbackId(base_id() + 1);
+  }
   virtual bool IsMonomorphic() OVERRIDE {
     return receiver_types_.length() == 1;
   }
   bool IsUninitialized() { return is_uninitialized_; }
   bool HasNoTypeInformation() {
     return is_uninitialized_;
   }
   virtual SmallMapList* GetReceiverTypes() OVERRIDE {
     return &receiver_types_;
   }
   virtual KeyedAccessStoreMode GetStoreMode() OVERRIDE {
     return store_mode_;
   }
   void set_is_uninitialized(bool b) { is_uninitialized_ = b; }
   void set_store_mode(KeyedAccessStoreMode mode) { store_mode_ = mode; }
 
  protected:
   Assignment(Zone* zone, Token::Value op, Expression* target, Expression* value,
              int pos, IdGen* id_gen);
 
+  static int num_ids() { return 2; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
+
   template<class Visitor>
   void Init(Zone* zone, AstNodeFactory<Visitor>* factory) {
     DCHECK(Token::IsAssignmentOp(op_));
     if (is_compound()) {
       binary_operation_ = factory->NewBinaryOperation(
           binary_op(), target_, value_, position() + 1);
     }
   }
 
  private:
   Token::Value op_;
   Expression* target_;
   Expression* value_;
   BinaryOperation* binary_operation_;
-  const BailoutId assignment_id_;
-
   bool is_uninitialized_ : 1;
   KeyedAccessStoreMode store_mode_ : 5;  // Windows treats as signed,
                                          // must have extra bit.
   SmallMapList receiver_types_;
 };
 
 
 class Yield FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(Yield)
@@ skipping 40 matching lines @@
   }
 
   int ValueFeedbackSlot() {
     DCHECK(yield_first_feedback_slot_ != kInvalidFeedbackSlot);
     return yield_first_feedback_slot_ + 2;
   }
 
  protected:
   Yield(Zone* zone, Expression* generator_object, Expression* expression,
         Kind yield_kind, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, 0, id_gen),
         generator_object_(generator_object),
         expression_(expression),
         yield_kind_(yield_kind),
         index_(-1),
         yield_first_feedback_slot_(kInvalidFeedbackSlot) {}
 
  private:
   Expression* generator_object_;
   Expression* expression_;
   Kind yield_kind_;
   int index_;
   int yield_first_feedback_slot_;
 };
 
 
 class Throw FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(Throw)
 
   Expression* exception() const { return exception_; }
 
  protected:
   Throw(Zone* zone, Expression* exception, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen), exception_(exception) {}
+      : Expression(zone, pos, 0, id_gen), exception_(exception) {}
 
  private:
   Expression* exception_;
 };
 
 
 class FunctionLiteral FINAL : public Expression {
  public:
   enum FunctionType {
     ANONYMOUS_EXPRESSION,
@@ skipping 133 matching lines @@
  protected:
   FunctionLiteral(Zone* zone, const AstRawString* 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, FunctionKind kind,
                   int position, IdGen* id_gen)
-      : Expression(zone, position, id_gen),
+      : Expression(zone, position, 0, id_gen),
         raw_name_(name),
         scope_(scope),
         body_(body),
         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) {
@@ skipping 46 matching lines @@
   Expression* extends() const { return extends_; }
   Expression* constructor() const { return constructor_; }
   ZoneList<Property*>* properties() const { return properties_; }
   int start_position() const { return position(); }
   int end_position() const { return end_position_; }
 
  protected:
   ClassLiteral(Zone* zone, const AstRawString* name, Expression* extends,
                Expression* constructor, ZoneList<Property*>* properties,
                int start_position, int end_position, IdGen* id_gen)
-      : Expression(zone, start_position, id_gen),
+      : Expression(zone, start_position, 0, id_gen),
         raw_name_(name),
         extends_(extends),
         constructor_(constructor),
         properties_(properties),
         end_position_(end_position) {}
 
  private:
   const AstRawString* raw_name_;
   Expression* extends_;
   Expression* constructor_;
   ZoneList<Property*>* properties_;
   int end_position_;
 };
 
 
 class NativeFunctionLiteral FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(NativeFunctionLiteral)
 
   Handle<String> name() const { return name_->string(); }
   v8::Extension* extension() const { return extension_; }
 
  protected:
   NativeFunctionLiteral(Zone* zone, const AstRawString* name,
                         v8::Extension* extension, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen), name_(name), extension_(extension) {}
+      : Expression(zone, pos, 0, id_gen), name_(name), extension_(extension) {}
 
  private:
   const AstRawString* name_;
   v8::Extension* extension_;
 };
 
 
 class ThisFunction FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(ThisFunction)
 
  protected:
   ThisFunction(Zone* zone, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen) {}
+      : Expression(zone, pos, 0, id_gen) {}
 };
 
 
 class SuperReference FINAL : public Expression {
  public:
   DECLARE_NODE_TYPE(SuperReference)
 
   VariableProxy* this_var() const { return this_var_; }
 
-  TypeFeedbackId HomeObjectFeedbackId() { return reuse(id()); }
+  TypeFeedbackId HomeObjectFeedbackId() {
+    return TypeFeedbackId(base_id() + 0);
+  }
 
   // Type feedback information.
   virtual int ComputeFeedbackSlotCount() { return FLAG_vector_ics ? 1 : 0; }
   virtual void SetFirstFeedbackSlot(int slot) {
     homeobject_feedback_slot_ = slot;
   }
 
   int HomeObjectFeedbackSlot() {
     DCHECK(!FLAG_vector_ics ||
            homeobject_feedback_slot_ != kInvalidFeedbackSlot);
     return homeobject_feedback_slot_;
   }
 
  protected:
   SuperReference(Zone* zone, VariableProxy* this_var, int pos, IdGen* id_gen)
-      : Expression(zone, pos, id_gen),
+      : Expression(zone, pos, num_ids(), id_gen),
         this_var_(this_var),
         homeobject_feedback_slot_(kInvalidFeedbackSlot) {
     DCHECK(this_var->is_this());
   }
 
+  static int num_ids() { return 1; }
+  int base_id() const { return Expression::base_id() + Expression::num_ids(); }
+
+ private:
   VariableProxy* this_var_;
   int homeobject_feedback_slot_;
 };
 
 
 #undef DECLARE_NODE_TYPE
 
 
 // ----------------------------------------------------------------------------
 // Regular expressions
@@ skipping 958 matching lines @@
   Zone* zone_;
   Visitor visitor_;
   AstValueFactory* ast_value_factory_;
   AstNode::IdGen* id_gen_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_AST_H_