[WIP] for-of iterator finalization

src/ast/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_AST_H_
 #define V8_AST_AST_H_
 
 #include "src/assembler.h"
 #include "src/ast/ast-value-factory.h"
 #include "src/ast/modules.h"
@@ skipping 865 matching lines @@
 };
 
 
 class ForOfStatement final : public ForEachStatement {
  public:
   DECLARE_NODE_TYPE(ForOfStatement)
 
   void Initialize(Expression* each,
                   Expression* subject,
                   Statement* body,
+                  Variable* iterator,
                   Expression* assign_iterator,
                   Expression* next_result,
                   Expression* result_done,
                   Expression* assign_each) {
     ForEachStatement::Initialize(each, subject, body);
+    iterator_ = iterator;
     assign_iterator_ = assign_iterator;
     next_result_ = next_result;
     result_done_ = result_done;
     assign_each_ = assign_each;
   }
 
   Expression* iterable() const {
     return subject();
   }
 
+  Variable* iterator() const {
+    return iterator_;
+  }
+

[neis, 2016/02/12 12:30:13]

Instead of having iterator_, we could extract the variable from assign_iterator
or next_result.

   // iterator = subject[Symbol.iterator]()
   Expression* assign_iterator() const {
     return assign_iterator_;
   }
 
   // result = iterator.next()  // with type check
   Expression* next_result() const {
     return next_result_;
   }
 
@@ skipping 14 matching lines @@
 
   BailoutId ContinueId() const override { return EntryId(); }
   BailoutId StackCheckId() const override { return BackEdgeId(); }
 
   static int num_ids() { return parent_num_ids() + 1; }
   BailoutId BackEdgeId() const { return BailoutId(local_id(0)); }
 
  protected:
   ForOfStatement(Zone* zone, ZoneList<const AstRawString*>* labels, int pos)
       : ForEachStatement(zone, labels, pos),
+        iterator_(NULL),
         assign_iterator_(NULL),
         next_result_(NULL),
         result_done_(NULL),
         assign_each_(NULL) {}
   static int parent_num_ids() { return ForEachStatement::num_ids(); }
 
  private:
   int local_id(int n) const { return base_id() + parent_num_ids() + n; }
 
+  Variable* iterator_;
   Expression* assign_iterator_;
   Expression* next_result_;
   Expression* result_done_;
   Expression* assign_each_;
 };
 
 
 class ExpressionStatement final : public Statement {
  public:
   DECLARE_NODE_TYPE(ExpressionStatement)
@@ skipping 2558 matching lines @@
   // the parser-level zone.
   Zone* parser_zone_;
   AstValueFactory* ast_value_factory_;
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_AST_AST_H_