for (double y : VALUES) {
        AtomicDouble a = new AtomicDouble(x);
        double z = a.accumulateAndGet(y, Double::max);
        double expectedMax = max(x, y);
        assertBitEquals(expectedMax, z);
        assertBitEquals(expectedMax, a.get());
      }
    }
  }

  /** getAndUpdate with sum stores sum of given value to current, and returns previous value */

      for (double x : VALUES) {
        for (double y : VALUES) {
          aa.set(i, x);
          double z = aa.accumulateAndGet(i, y, Double::max);
          double expectedMax = max(x, y);
          assertBitEquals(expectedMax, z);
          assertBitEquals(expectedMax, aa.get(i));
        }
      }
    }
  }

  /** getAndUpdate adds given value to current, and returns previous value */