assertAligned(start.toInt()); assertAligned(bytes.toInt());
assertAligned(start); assertAligned(bytes);
  public static void zero(Address start, Extent bytes) throws InlinePragma {    if (Assert.VERIFY_ASSERTIONS) {      assertAligned(start.toInt());      assertAligned(bytes.toInt());    }    if (bytes.GT(Extent.fromIntZeroExtend(SMALL_REGION_THRESHOLD)))       org.mmtk.vm.Memory.zero(start, bytes);    else      zeroSmall(start, bytes);  }