Create a separate space for global property cells

src/globals.h

 // Copyright 2006-2009 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 243 matching lines @@
 // Miscellaneous
 
 // NOTE: SpaceIterator depends on AllocationSpace enumeration values being
 // consecutive.
 enum AllocationSpace {
   NEW_SPACE,          // Semispaces collected with copying collector.
   OLD_POINTER_SPACE,  // Must be first of the paged spaces - see PagedSpaces.
   OLD_DATA_SPACE,     // May not have pointers to new space.
   CODE_SPACE,         // Also one of the old spaces.  Marked executable.
   MAP_SPACE,          // Only map objects.
+  GLOBAL_PROPERTY_CELL_SPACE,  // Only global property cell objects.
   LO_SPACE,           // Large objects.
   FIRST_SPACE = NEW_SPACE,
-  LAST_SPACE = LO_SPACE  // <= 5 (see kSpaceBits and kLOSpacePointer)
+  LAST_SPACE = LO_SPACE  // <= 9 (see kSpaceBits and kLOSpacePointer)
 };
-const int kSpaceTagSize = 3;
+const int kSpaceTagSize = 4;
 const int kSpaceTagMask = (1 << kSpaceTagSize) - 1;
 
 
 // A flag that indicates whether objects should be pretenured when
 // allocated (allocated directly into the old generation) or not
 // (allocated in the young generation if the object size and type
 // allows).
 enum PretenureFlag { NOT_TENURED, TENURED };
 
 enum GarbageCollector { SCAVENGER, MARK_COMPACTOR };
@@ skipping 278 matching lines @@
 
   Dest dest;
   memcpy(&dest, &source, sizeof(dest));
   return dest;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_GLOBALS_H_