Properly filter types using the initial map from HAllocate.

src/ast.h

 // 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 270 matching lines @@
   void AddMapIfMissing(Handle<Map> map, Zone* zone) {
     Map* updated = map->CurrentMapForDeprecated();
     if (updated == NULL) return;
     map = Handle<Map>(updated);
     for (int i = 0; i < length(); ++i) {
       if (at(i).is_identical_to(map)) return;
     }
     Add(map, zone);
   }
 
+  void FilterForPossibleTransitions(Map* root_map, Zone* zone) {

[Michael Starzinger, 2013/09/05 20:07:23]

The "zone" parameter is obsolete, as we only remove elements with this method
and don't add new ones.

[Toon Verwaest, 2013/09/06 09:23:12]

Done.

+    for (int i = list_.length() - 1; i >= 0; i--) {
+      if (at(i)->FindRootMap() != root_map) {
+        list_.RemoveElement(list_.at(i));
+      }
+    }
+  }
+
   void Add(Handle<Map> handle, Zone* zone) {
     list_.Add(handle.location(), zone);
   }
 
   Handle<Map> at(int i) const {
     return Handle<Map>(list_.at(i));
   }
 
   Handle<Map> first() const { return at(0); }
   Handle<Map> last() const { return at(length() - 1); }
@@ skipping 2954 matching lines @@
  private:
   Isolate* isolate_;
   Zone* zone_;
   Visitor visitor_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_AST_H_