Provide baseline for experimental GC implementation.

src/spaces.h

 // Copyright 2006-2008 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 2045 matching lines @@
 
 // -----------------------------------------------------------------------------
 // Old space for all map objects
 
 class MapSpace : public FixedSpace {
  public:
   // Creates a map space object with a maximum capacity.
   MapSpace(intptr_t max_capacity, int max_map_space_pages, AllocationSpace id)
       : FixedSpace(max_capacity, id, Map::kSize, "map"),
         max_map_space_pages_(max_map_space_pages) {
-    ASSERT(max_map_space_pages < kMaxMapPageIndex);
   }
 
   // Prepares for a mark-compact GC.
   virtual void PrepareForMarkCompact(bool will_compact);
 
   // Given an index, returns the page address.
-  Address PageAddress(int page_index) { return page_addresses_[page_index]; }
-
-  static const int kMaxMapPageIndex = 1 << MapWord::kMapPageIndexBits;
+  // TODO(gc): this limit is artifical just to keep code compilable
+  static const int kMaxMapPageIndex = 1 << 16;
 
   // Are map pointers encodable into map word?
   bool MapPointersEncodable() {
-    if (!FLAG_use_big_map_space) {
-      ASSERT(CountPagesToTop() <= kMaxMapPageIndex);
-      return true;
-    }
-    return CountPagesToTop() <= max_map_space_pages_;
+    return false;
   }
 
   // Should be called after forced sweep to find out if map space needs
   // compaction.
   bool NeedsCompaction(int live_maps) {
     return !MapPointersEncodable() && live_maps <= CompactionThreshold();
   }
 
   Address TopAfterCompaction(int live_maps) {
     ASSERT(NeedsCompaction(live_maps));
@@ skipping 50 matching lines @@
  private:
   static const int kMapsPerPage = Page::kObjectAreaSize / Map::kSize;
 
   // Do map space compaction if there is a page gap.
   int CompactionThreshold() {
     return kMapsPerPage * (max_map_space_pages_ - 1);
   }
 
   const int max_map_space_pages_;
 
-  // An array of page start address in a map space.
-  Address page_addresses_[kMaxMapPageIndex];
-
  public:
   TRACK_MEMORY("MapSpace")
 };
 
 
 // -----------------------------------------------------------------------------
 // Old space for all global object property cell objects
 
 class CellSpace : public FixedSpace {
  public:
@@ skipping 181 matching lines @@
 
  private:
   LargeObjectChunk* current_;
   HeapObjectCallback size_func_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_H_