Record the addresses of pages that are unmapped to aid

src/mark-compact.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3409 matching lines @@
 
   slots_buffer_allocator_.DeallocateChain(&migration_slots_buffer_);
   ASSERT(migration_slots_buffer_ == NULL);
   for (int i = 0; i < npages; i++) {
     Page* p = evacuation_candidates_[i];
     if (!p->IsEvacuationCandidate()) continue;
     PagedSpace* space = static_cast<PagedSpace*>(p->owner());
     space->Free(p->area_start(), p->area_size());
     p->set_scan_on_scavenge(false);
     slots_buffer_allocator_.DeallocateChain(p->slots_buffer_address());
-    p->ClearEvacuationCandidate();
     p->ResetLiveBytes();
     space->ReleasePage(p);
   }
   evacuation_candidates_.Rewind(0);
   compacting_ = false;
 }
 
 
 static const int kStartTableEntriesPerLine = 5;
 static const int kStartTableLines = 171;
@@ skipping 690 matching lines @@
   while (buffer != NULL) {
     SlotsBuffer* next_buffer = buffer->next();
     DeallocateBuffer(buffer);
     buffer = next_buffer;
   }
   *buffer_address = NULL;
 }
 
 
 } }  // namespace v8::internal