Extent size = Word.fromInt(SpaceDescriptor.getChunks(descriptor)).lsh(LOG_BYTES_IN_CHUNK).toExtent();
Extent size = Word.fromIntSignExtend(SpaceDescriptor.getChunks(descriptor)).lsh(LOG_BYTES_IN_CHUNK).toExtent();
  public static boolean isInSpace(int descriptor, ObjectReference object)    throws InlinePragma {    if (!SpaceDescriptor.isContiguous(descriptor)) {      return getDescriptorForObject(object) == descriptor;    } else {      Address addr = ObjectModel.refToAddress(object);      Address start = SpaceDescriptor.getStart(descriptor);      if (!Assert.VERIFY_ASSERTIONS &&          SpaceDescriptor.isContiguousHi(descriptor))        return addr.GE(start);      else {        Extent size = Word.fromInt(SpaceDescriptor.getChunks(descriptor)).lsh(LOG_BYTES_IN_CHUNK).toExtent();        Address end = start.add(size);        return addr.GE(start) && addr.LT(end);      }    }  }