## src/java.base/share/classes/java/lang/StrictMath.java

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rev 10702 : 4477961: java.lang.Math.toDegrees(double) could be optimized
Summary: Change toDegrees() and toRadians() to multiplication by a compile-time constant.
Reviewed-by: mduigou, shade

*** 96,105 ****
--- 96,117 ----
* diameter.
*/
public static final double PI = 3.14159265358979323846;
/**
+ * Constant by which to multiply an angular value in degrees to obtain an
+ * angular value in radians.
+ */
+ private static final double DEGREES_TO_RADIANS = 0.017453292519943295;
+
+ /**
+ * Constant by which to multiply an angular value in radians to obtain an
+ * angular value in degrees.
+ */
+
+ private static final double RADIANS_TO_DEGREES = 57.29577951308232;
+ /**
* Returns the trigonometric sine of an angle. Special cases:
* <ul><li>If the argument is NaN or an infinity, then the
* result is NaN.
* <li>If the argument is zero, then the result is a zero with the
* same sign as the argument.</ul>

*** 177,187 ****
* in radians.
*/
public static strictfp double toRadians(double angdeg) {
// Do not delegate to Math.toRadians(angdeg) because
// this method has the strictfp modifier.
! return angdeg / 180.0 * PI;
}
/**
* Converts an angle measured in radians to an approximately
* equivalent angle measured in degrees. The conversion from
--- 189,199 ----
* in radians.
*/
public static strictfp double toRadians(double angdeg) {
// Do not delegate to Math.toRadians(angdeg) because
// this method has the strictfp modifier.
! return angdeg * DEGREES_TO_RADIANS;
}
/**
* Converts an angle measured in radians to an approximately
* equivalent angle measured in degrees. The conversion from

*** 194,204 ****
* in degrees.
*/
public static strictfp double toDegrees(double angrad) {
// Do not delegate to Math.toDegrees(angrad) because
// this method has the strictfp modifier.
! return angrad * 180.0 / PI;
}
/**
* Returns Euler's number <i>e</i> raised to the power of a
* {@code double} value. Special cases:
--- 206,216 ----
* in degrees.
*/
public static strictfp double toDegrees(double angrad) {
// Do not delegate to Math.toDegrees(angrad) because
// this method has the strictfp modifier.
! return angrad * RADIANS_TO_DEGREES;
}
/**
* Returns Euler's number <i>e</i> raised to the power of a
* {@code double} value. Special cases: