// Double#doubleToRawLongBits(double)} spec.
  static final long SIGNIFICAND_MASK = 0x000fffffffffffffL;

  // The mask for the exponent, according to the {@link
  // Double#doubleToRawLongBits(double)} spec.
  static final long EXPONENT_MASK = 0x7ff0000000000000L;

  // The mask for the sign, according to the {@link
  // Double#doubleToRawLongBits(double)} spec.

 * Double#doubleToRawLongBits}, which differs from both the primitive double {@code ==} operator and
 * from {@link Double#equals}, as if implemented by:
 *
 * <pre>{@code
 * static boolean bitEquals(double x, double y) {
 *   long xBits = Double.doubleToRawLongBits(x);
 *   long yBits = Double.doubleToRawLongBits(y);
 *   return xBits == yBits;
 * }
 * }</pre>
 *

  // Double#doubleToRawLongBits(double)} spec.
  static final long SIGNIFICAND_MASK = 0x000fffffffffffffL;

  // The mask for the exponent, according to the {@link
  // Double#doubleToRawLongBits(double)} spec.
  static final long EXPONENT_MASK = 0x7ff0000000000000L;

  // The mask for the sign, according to the {@link
  // Double#doubleToRawLongBits(double)} spec.

  };

  /** The notion of equality used by AtomicDouble */
  static boolean bitEquals(double x, double y) {
    return Double.doubleToRawLongBits(x) == Double.doubleToRawLongBits(y);
  }

  static void assertBitEquals(double x, double y) {
    assertEquals(Double.doubleToRawLongBits(x), Double.doubleToRawLongBits(y));
  }

  /** constructor initializes to given value */
  public void testConstructor() {
    for (double x : VALUES) {

    for (int i = 0; i < reps; i++) {
      int j = i & ARRAY_MASK;
      tmp += Double.doubleToRawLongBits(DoubleMath.log2(positiveDoubles[j]));
    }
    return tmp;
  }

  @Benchmark
  long factorial(int reps) {
    long tmp = 0;
    for (int i = 0; i < reps; i++) {
      int j = i & ARRAY_MASK;
      tmp += Double.doubleToRawLongBits(DoubleMath.factorial(factorials[j]));
    }
    return tmp;
  }

  @Benchmark

    assertThrows(IllegalArgumentException.class, () -> DoubleUtils.ensureNonNegative(Double.NaN));
  }

  public void testOneBits() {
    assertEquals(DoubleUtils.ONE_BITS, Double.doubleToRawLongBits(1.0));
  }

  private static void failFormat(String template, Object... args) {
    fail(String.format(template, args));
  }

  };

  /** The notion of equality used by AtomicDoubleArray */
  static boolean bitEquals(double x, double y) {
    return Double.doubleToRawLongBits(x) == Double.doubleToRawLongBits(y);
  }

  static void assertBitEquals(double x, double y) {
    assertEquals(Double.doubleToRawLongBits(x), Double.doubleToRawLongBits(y));
  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNulls() {

    }
    return tmp;
  }

  @Benchmark
  long roundToDouble(int reps) {
    long tmp = 0;
    for (int i = 0; i < reps; i++) {
      int j = i & ARRAY_MASK;
      tmp += Double.doubleToRawLongBits(BigIntegerMath.roundToDouble(nonzero1[j], mode));
    }
    return tmp;
  }

  public final Hasher putBoolean(boolean b) {
    return putByte(b ? (byte) 1 : (byte) 0);
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putDouble(double d) {
    return putLong(Double.doubleToRawLongBits(d));
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putFloat(float f) {
    return putInt(Float.floatToRawIntBits(f));
  }

  @Override
  @CanIgnoreReturnValue

  public final Hasher putBoolean(boolean b) {
    return putByte(b ? (byte) 1 : (byte) 0);
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putDouble(double d) {
    return putLong(Double.doubleToRawLongBits(d));
  }

  @Override
  @CanIgnoreReturnValue
  public final Hasher putFloat(float f) {
    return putInt(Float.floatToRawIntBits(f));
  }

  @Override
  @CanIgnoreReturnValue