@GwtIncompatible
public class BigDecimalMath {
  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}.
   *

 *
 * @author Louis Wasserman
 * @since 11.0
 */
@GwtCompatible
public final class DoubleMath {
  /*
   * This method returns a value y such that rounding y DOWN (towards zero) gives the same result as
   * rounding x according to the specified mode.
   */
  @GwtIncompatible // #isMathematicalInteger, com.google.common.math.DoubleUtils
  static double roundIntermediate(double x, RoundingMode mode) {

  }

  /**
   * 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}.
   *

    // So we can ignore the bottom 11, except for rounding. We can unsigned-shift right 1, aka
    // unsigned-divide by 2, and convert that. Then we'll get exactly half of the desired double
    // value. But in the specific case where the bottom two bits of the original number are 01, we
    // want to replace that with 1 in the shifted value for correct rounding.
    return (double) ((value >>> 1) | (value & 1)) * 2.0;
  }

    // to make sure bit twiddling works as expected.
    return ~~(x - y) >>> (Integer.SIZE - 1);
  }

  /**
   * Returns the base-2 logarithm of {@code x}, rounded according to the specified rounding mode.
   *
   * @throws IllegalArgumentException if {@code x <= 0}
   * @throws ArithmeticException if {@code mode} is {@link RoundingMode#UNNECESSARY} and {@code x}
   *     is not a power of two
   */

  public void testLog2HalfEven() {
    for (BigInteger x : POSITIVE_BIGINTEGER_CANDIDATES) {
      int halfEven = BigIntegerMath.log2(x, HALF_EVEN);
      // Now figure out what rounding mode we should behave like (it depends if FLOOR was
      // odd/even).
      boolean floorWasEven = (BigIntegerMath.log2(x, FLOOR) & 1) == 0;

import com.google.caliper.BeforeExperiment;
import com.google.caliper.Benchmark;
import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks for the non-rounding methods of {@code IntMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class IntMathBenchmark {
  private static final int[] exponent = new int[ARRAY_SIZE];

   * 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

import com.google.caliper.BeforeExperiment;
import com.google.caliper.Benchmark;
import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks for the non-rounding methods of {@code IntMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class IntMathBenchmark {
  private static final int[] exponent = new int[ARRAY_SIZE];

      return x.longValue();
    } else if (exponent > MAX_EXPONENT) {
      return x.signum() * POSITIVE_INFINITY;
    }

    /*
     * We need the top SIGNIFICAND_BITS + 1 bits, including the "implicit" one bit. To make rounding
     * easier, we pick out the top SIGNIFICAND_BITS + 2 bits, so we have one to help us round up or
     * down. twiceSignifFloor will contain the top SIGNIFICAND_BITS + 2 bits, and signifFloor the
     * top SIGNIFICAND_BITS + 1.