at.set(x);
      assertEquals((float) x, at.floatValue());
    }
  }

  /** doubleValue returns current value. */
  public void testDoubleValue() {
    AtomicDouble at = new AtomicDouble();
    assertEquals(0.0d, at.doubleValue());
    for (double x : VALUES) {
      at.set(x);
      assertBitEquals(x, at.doubleValue());
    }
  }

  /** compareAndSet treats +0.0 and -0.0 as distinct values */