- Implement the old sweeper.

vm/heap.h

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_HEAP_H_
 #define VM_HEAP_H_
 
 #include "vm/allocation.h"
 #include "vm/flags.h"
 #include "vm/globals.h"
 
 namespace dart {
 
 // Forward declarations.
 class Isolate;
 class ObjectPointerVisitor;
 class PageSpace;
 class Scavenger;
 class VirtualMemory;
 
 DECLARE_FLAG(bool, verbose_gc);
+DECLARE_FLAG(bool, verify_before_gc);
+DECLARE_FLAG(bool, verify_after_gc);
 DECLARE_FLAG(bool, gc_at_alloc);
 
 class Heap {
  public:
   enum Space {
     kNew,
     kOld,
     kExecutable
   };
 
@@ skipping 17 matching lines @@
     return 0;
   }
 
   // Heap contains the specified address.
   bool Contains(uword addr) const;
   bool CodeContains(uword addr) const;
 
   // Visit all pointers in the space.
   void IterateNewPointers(ObjectPointerVisitor* visitor);
   void IterateOldPointers(ObjectPointerVisitor* visitor);
+  void IterateCodePointers(ObjectPointerVisitor* visitor);
 
   void CollectGarbage(Space space);
   void CollectAllGarbage();
 
   // Accessors for inlined allocation in generated code.
   uword TopAddress();
   uword EndAddress();
   static intptr_t new_space_offset() { return OFFSET_OF(Heap, new_space_); }
 
   // Initialize the heap and register it with the isolate.
@@ skipping 31 matching lines @@
  public:
   NoGCScope() {}
  private:
   DISALLOW_COPY_AND_ASSIGN(NoGCScope);
 };
 #endif  // defined(DEBUG)
 
 }  // namespace dart
 
 #endif  // VM_HEAP_H_