for (double x : VALUES) {
      assertBitEquals(prev, at.getAndSet(x));
      prev = x;
    }
  }

  /** getAndAdd returns previous value and adds given value */
  public void testGetAndAdd() {
    for (double x : VALUES) {
      for (double y : VALUES) {
        AtomicDouble a = new AtomicDouble(x);
        double z = a.getAndAdd(y);
        assertBitEquals(x, z);