1 files changed, 176 insertions, 0 deletions
diff --git a/libjava/java/lang/Math.java b/libjava/java/lang/Math.java
index 08081e2..6f68480 100644
--- a/libjava/java/lang/Math.java
+++ b/libjava/java/lang/Math.java
@@ -647,4 +647,180 @@ public final class Math
   {
     return (rads * 180) / PI;
   }
+
+  /**
+   * <p>
+   * Returns the base 10 logarithm of the supplied value.  The returned
+   * result is within 1 ulp of the exact result, and the results are
+   * semi-monotonic.
+   * </p>
+   * <p>
+   * Arguments of either <code>NaN</code> or less than zero return
+   * <code>NaN</code>.  An argument of positive infinity returns positive
+   * infinity.  Negative infinity is returned if either positive or negative
+   * zero is supplied.  Where the argument is the result of
+   * <code>10<sup>n</sup</code>, then <code>n</code> is returned.
+   * </p>
+   *
+   * @param a the numeric argument.
+   * @return the base 10 logarithm of <code>a</code>.
+   * @since 1.5
+   */
+  public static native double log10(double a);
+
+  /**
+   * <p>
+   * Returns the sign of the argument as follows:
+   * </p>
+   * <ul>
+   * <li>If <code>a</code> is greater than zero, the result is 1.0.</li>
+   * <li>If <code>a</code> is less than zero, the result is -1.0.</li>
+   * <li>If <code>a</code> is <code>NaN</code>, the result is <code>NaN</code>.
+   * <li>If <code>a</code> is positive or negative zero, the result is the
+   * same.</li>
+   * </ul>
+   *
+   * @param a the numeric argument.
+   * @return the sign of the argument.
+   * @since 1.5.
+   */
+  public static double signum(double a)
+  {
+    if (Double.isNaN(a))
+      return Double.NaN;
+    if (a > 0)
+      return 1.0;
+    if (a < 0)
+      return -1.0;
+    return a;
+  }
+
+  /**
+   * <p>
+   * Returns the sign of the argument as follows:
+   * </p>
+   * <ul>
+   * <li>If <code>a</code> is greater than zero, the result is 1.0f.</li>
+   * <li>If <code>a</code> is less than zero, the result is -1.0f.</li>
+   * <li>If <code>a</code> is <code>NaN</code>, the result is <code>NaN</code>.
+   * <li>If <code>a</code> is positive or negative zero, the result is the
+   * same.</li>
+   * </ul>
+   *
+   * @param a the numeric argument.
+   * @return the sign of the argument.
+   * @since 1.5.
+   */
+  public static float signum(float a)
+  {
+    if (Float.isNaN(a))
+      return Float.NaN;
+    if (a > 0)
+      return 1.0f;
+    if (a < 0)
+      return -1.0f;
+    return a;
+  }
+
+  /**
+   * Return the ulp for the given double argument.  The ulp is the
+   * difference between the argument and the next larger double.  Note
+   * that the sign of the double argument is ignored, that is,
+   * ulp(x) == ulp(-x).  If the argument is a NaN, then NaN is returned.
+   * If the argument is an infinity, then +Inf is returned.  If the
+   * argument is zero (either positive or negative), then
+   * {@link Double#MIN_VALUE} is returned.
+   * @param d the double whose ulp should be returned
+   * @return the difference between the argument and the next larger double
+   * @since 1.5
+   */
+  public static double ulp(double d)
+  {
+    if (Double.isNaN(d))
+      return d;
+    if (Double.isInfinite(d))
+      return Double.POSITIVE_INFINITY;
+    // This handles both +0.0 and -0.0.
+    if (d == 0.0)
+      return Double.MIN_VALUE;
+    long bits = Double.doubleToLongBits(d);
+    final int mantissaBits = 52;
+    final int exponentBits = 11;
+    final long mantMask = (1L << mantissaBits) - 1;
+    long mantissa = bits & mantMask;
+    final long expMask = (1L << exponentBits) - 1;
+    long exponent = (bits >>> mantissaBits) & expMask;
+
+    // Denormal number, so the answer is easy.
+    if (exponent == 0)
+      {
+        long result = (exponent << mantissaBits) | 1L;
+        return Double.longBitsToDouble(result);
+      }
+
+    // Conceptually we want to have '1' as the mantissa.  Then we would
+    // shift the mantissa over to make a normal number.  If this underflows
+    // the exponent, we will make a denormal result.
+    long newExponent = exponent - mantissaBits;
+    long newMantissa;
+    if (newExponent > 0)
+      newMantissa = 0;
+    else
+      {
+        newMantissa = 1L << -(newExponent - 1);
+        newExponent = 0;
+      }
+    return Double.longBitsToDouble((newExponent << mantissaBits) | newMantissa);
+  }
+
+  /**
+   * Return the ulp for the given float argument.  The ulp is the
+   * difference between the argument and the next larger float.  Note
+   * that the sign of the float argument is ignored, that is,
+   * ulp(x) == ulp(-x).  If the argument is a NaN, then NaN is returned.
+   * If the argument is an infinity, then +Inf is returned.  If the
+   * argument is zero (either positive or negative), then
+   * {@link Float#MIN_VALUE} is returned.
+   * @param f the float whose ulp should be returned
+   * @return the difference between the argument and the next larger float
+   * @since 1.5
+   */
+  public static float ulp(float f)
+  {
+    if (Float.isNaN(f))
+      return f;
+    if (Float.isInfinite(f))
+      return Float.POSITIVE_INFINITY;
+    // This handles both +0.0 and -0.0.
+    if (f == 0.0)
+      return Float.MIN_VALUE;
+    int bits = Float.floatToIntBits(f);
+    final int mantissaBits = 23;
+    final int exponentBits = 8;
+    final int mantMask = (1 << mantissaBits) - 1;
+    int mantissa = bits & mantMask;
+    final int expMask = (1 << exponentBits) - 1;
+    int exponent = (bits >>> mantissaBits) & expMask;
+
+    // Denormal number, so the answer is easy.
+    if (exponent == 0)
+      {
+        int result = (exponent << mantissaBits) | 1;
+        return Float.intBitsToFloat(result);
+      }
+
+    // Conceptually we want to have '1' as the mantissa.  Then we would
+    // shift the mantissa over to make a normal number.  If this underflows
+    // the exponent, we will make a denormal result.
+    int newExponent = exponent - mantissaBits;
+    int newMantissa;
+    if (newExponent > 0)
+      newMantissa = 0;
+    else
+      {
+        newMantissa = 1 << -(newExponent - 1);
+        newExponent = 0;
+      }
+    return Float.intBitsToFloat((newExponent << mantissaBits) | newMantissa);
+  }
 }