private BigDecimalMath() {}

  /**
   * Returns {@code x}, rounded to a {@code double} with the specified rounding mode. If {@code x}
   * is precisely representable as a {@code double}, its {@code double} value will be returned;
   * otherwise, the rounding will choose between the two nearest representable values with {@code
   * mode}.
   *
   * <p>For the case of {@link RoundingMode#HALF_DOWN}, {@code HALF_UP}, and {@code HALF_EVEN},

        .setExpectation(Math.pow(2, 53), RoundingMode.values())
        .test();
  }

  public void testRoundToDouble_maxPreciselyRepresentablePlusOne() {
    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(Math.pow(2, 53), RoundingMode.values())
        .test();
  }

  public void testRoundToDouble_maxPreciselyRepresentablePlusOne() {
    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))

import static java.lang.Math.nextDown;
import static java.lang.Math.nextUp;

import com.google.common.annotations.GwtIncompatible;
import java.math.RoundingMode;

/**
 * Helper type to implement rounding {@code X} to a representable {@code double} value according to
 * a {@link RoundingMode}.
 */
@GwtIncompatible
abstract class ToDoubleRounder<X extends Number & Comparable<X>> {
  /**

  }

  /**
   * Returns {@code x}, rounded to a {@code double} with the specified rounding mode. If {@code x}
   * is precisely representable as a {@code double}, its {@code double} value will be returned;
   * otherwise, the rounding will choose between the two nearest representable values with {@code
   * mode}.
   *
   * <p>For the case of {@link RoundingMode#HALF_DOWN}, {@code HALF_UP}, and {@code HALF_EVEN},

        .test();
  }

  @J2ktIncompatible
  @GwtIncompatible
  public void testRoundToDouble_maxPreciselyRepresentablePlusOne() {
    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))

 * signal on 32 bit devices running Android Q.
 */
@GwtIncompatible
final class OverflowAvoidingLockSupport {
  // Represents the max nanoseconds representable on a linux timespec with a 32 bit tv_sec
  static final long MAX_NANOSECONDS_THRESHOLD = (1L + Integer.MAX_VALUE) * 1_000_000_000L - 1L;

  private OverflowAvoidingLockSupport() {}

   * is precisely representable as a {@code double}, its {@code double} value will be returned;
   * otherwise, the rounding will choose between the two nearest representable values with {@code
   * mode}.
   *
   * <p>For the case of {@link RoundingMode#HALF_EVEN}, this implementation uses the IEEE 754
   * default rounding mode: if the two nearest representable values are equally near, the one with

   * @throws ArithmeticException of the next-higher power of two is not representable as an {@code
   *     int}, i.e. when {@code x > 2^30}
   * @since 20.0
   */
  public static int ceilingPowerOfTwo(int x) {
    checkPositive("x", x);
    if (x > MAX_SIGNED_POWER_OF_TWO) {
      throw new ArithmeticException("ceilingPowerOfTwo(" + x + ") not representable as an int");
    }
    return 1 << -Integer.numberOfLeadingZeros(x - 1);
  }

<a href="#Complex_numbers">components</a> <code>real(x)</code> and <code>imag(x)</code>
are representable by values of <code>T</code>'s component type (<code>float32</code> or
<code>float64</code>).
</li>
</ul>

<p>
If <code>T</code> is a type parameter,
<code>x</code> is representable by a value of type <code>T</code> if <code>x</code> is representable
by a value of each type in <code>T</code>'s type set.
</p>

<pre>