double twoToThe53 = Math.pow(2, 53);
    // the representable doubles are 2^53 and 2^53 + 2.
    // 2^53+1 is halfway between, so HALF_UP will go up and HALF_DOWN will go down.
    new RoundToDoubleTester(BigDecimal.valueOf((1L << 53) + 1))
        .setExpectation(twoToThe53, DOWN, FLOOR, HALF_DOWN, HALF_EVEN)
        .setExpectation(nextUp(twoToThe53), CEILING, UP, HALF_UP)
        .roundUnnecessaryShouldThrow()
        .test();
  }

    double twoToThe53 = Math.pow(2, 53);
    // the representable doubles are 2^53 and 2^53 + 2.
    // 2^53+1 is halfway between, so HALF_UP will go up and HALF_DOWN will go down.
    new RoundToDoubleTester(BigInteger.valueOf((1L << 53) + 1))
        .setExpectation(twoToThe53, DOWN, FLOOR, HALF_DOWN, HALF_EVEN)
        .setExpectation(nextUp(twoToThe53), CEILING, UP, HALF_UP)
        .roundUnnecessaryShouldThrow()
        .test();
  }

    double twoToThe53 = Math.pow(2, 53);
    // the representable doubles are 2^53 and 2^53 + 2.
    // 2^53+1 is halfway between, so HALF_UP will go up and HALF_DOWN will go down.
    new RoundToDoubleTester(BigDecimal.valueOf((1L << 53) + 1))
        .setExpectation(twoToThe53, DOWN, FLOOR, HALF_DOWN, HALF_EVEN)
        .setExpectation(nextUp(twoToThe53), CEILING, UP, HALF_UP)
        .roundUnnecessaryShouldThrow()
        .test();
  }

    checkNotNull(mode, "mode");
    double roundArbitrarily = roundToDoubleArbitrarily(x);
    if (Double.isInfinite(roundArbitrarily)) {
      switch (mode) {
        case DOWN:
        case HALF_EVEN:
        case HALF_DOWN:
        case HALF_UP:
          return Double.MAX_VALUE * sign(x);
        case FLOOR:
          return (roundArbitrarily == Double.POSITIVE_INFINITY)
              ? Double.MAX_VALUE

 * Benchmarks for the rounding methods of {@code LongMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class LongMathRoundingBenchmark {
  @Param({"DOWN", "UP", "FLOOR", "CEILING", "HALF_EVEN", "HALF_UP", "HALF_DOWN"})
  RoundingMode mode;

  private static final long[] positive = new long[ARRAY_SIZE];
  private static final long[] nonzero = new long[ARRAY_SIZE];
  private static final long[] longs = new long[ARRAY_SIZE];

  private static final BigInteger[] nonzero2 = new BigInteger[ARRAY_SIZE];
  private static final BigInteger[] positive = new BigInteger[ARRAY_SIZE];

  @Param({"DOWN", "UP", "FLOOR", "CEILING", "HALF_EVEN", "HALF_UP", "HALF_DOWN"})
  RoundingMode mode;

  @BeforeExperiment
  void setUp() {
    for (int i = 0; i < ARRAY_SIZE; i++) {
      positive[i] = randomPositiveBigInteger(1024);
      nonzero1[i] = randomNonZeroBigInteger(1024);

  private static final BigInteger[] nonzero2 = new BigInteger[ARRAY_SIZE];
  private static final BigInteger[] positive = new BigInteger[ARRAY_SIZE];

  @Param({"DOWN", "UP", "FLOOR", "CEILING", "HALF_EVEN", "HALF_UP", "HALF_DOWN"})
  RoundingMode mode;

  @BeforeExperiment
  void setUp() {
    for (int i = 0; i < ARRAY_SIZE; i++) {
      positive[i] = randomPositiveBigInteger(1024);
      nonzero1[i] = randomNonZeroBigInteger(1024);

      case DOWN:
      case FLOOR:
        return logFloor;

      case UP:
      case CEILING:
        return isPowerOfTwo(x) ? logFloor : logFloor + 1;

      case HALF_DOWN:
      case HALF_UP:
      case HALF_EVEN:
        if (logFloor < SQRT2_PRECOMPUTE_THRESHOLD) {
          BigInteger halfPower =
              SQRT2_PRECOMPUTED_BITS.shiftRight(SQRT2_PRECOMPUTE_THRESHOLD - logFloor);

 * Benchmarks for the rounding methods of {@code LongMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class LongMathRoundingBenchmark {
  @Param({"DOWN", "UP", "FLOOR", "CEILING", "HALF_EVEN", "HALF_UP", "HALF_DOWN"})
  RoundingMode mode;

  private static final long[] positive = new long[ARRAY_SIZE];
  private static final long[] nonzero = new long[ARRAY_SIZE];
  private static final long[] longs = new long[ARRAY_SIZE];

      nonzero[i] = randomNonZeroBigInteger(Integer.SIZE - 2).intValue();
      ints[i] = RANDOM_SOURCE.nextInt();
    }
  }

  @Param({"DOWN", "UP", "FLOOR", "CEILING", "HALF_EVEN", "HALF_UP", "HALF_DOWN"})
  RoundingMode mode;

  @Benchmark
  int log2(int reps) {
    int tmp = 0;
    for (int i = 0; i < reps; i++) {
      int j = i & ARRAY_MASK;
      tmp += IntMath.log2(positive[j], mode);
    }