X64: Checked and slightly modified Object layouts to be compatible with 64-bit pointers.

src/objects-inl.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 1776 matching lines @@
   if (instance_type == JS_OBJECT_TYPE) return  map->instance_size();
   if (instance_type == FIXED_ARRAY_TYPE) {
     return reinterpret_cast<FixedArray*>(this)->FixedArraySize();
   }
   // Otherwise do the general size computation.
   return SlowSizeFromMap(map);
 }
 
 
 void Map::set_instance_size(int value) {
-  ASSERT((value & ~(kPointerSize - 1)) == value);
+  ASSERT_EQ((value & ~(kPointerSize - 1)), value);
   value >>= kPointerSizeLog2;
   ASSERT(0 <= value && value < 256);
   WRITE_BYTE_FIELD(this, kInstanceSizeOffset, static_cast<byte>(value));
 }
 
 
 void Map::set_inobject_properties(int value) {
   ASSERT(0 <= value && value < 256);
   WRITE_BYTE_FIELD(this, kInObjectPropertiesOffset, static_cast<byte>(value));
 }
@@ skipping 820 matching lines @@
 #undef WRITE_INT_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_