double unused = Math.E + Math.PI;
      for (double x : VALUES) {
        assertBitEquals(prev, aa.get(i));
        assertFalse(aa.weakCompareAndSet(i, unused, x));
        assertBitEquals(prev, aa.get(i));
        while (!aa.weakCompareAndSet(i, prev, x)) {
          ;
        }
        assertBitEquals(x, aa.get(i));
        prev = x;
      }
    }
  }

   *
   * @param expect the expected value
   * @param update the new value
   * @return {@code true} if successful
   */
  public final boolean weakCompareAndSet(double expect, double update) {
    return updater.weakCompareAndSet(
        this, doubleToRawLongBits(expect), doubleToRawLongBits(update));
  }

  /**
   * Atomically adds the given value to the current value.
   *

   *
   * @param i the index
   * @param expect the expected value
   * @param update the new value
   * @return true if successful
   */
  public final boolean weakCompareAndSet(int i, double expect, double update) {
    return longs.weakCompareAndSet(i, doubleToRawLongBits(expect), doubleToRawLongBits(update));
  }

  /**
   * Atomically adds the given value to the element at index {@code i}.
   *