# HG changeset patch
# User bpb
# Date 1411430363 25200
# Node ID b4e26e7f964e8e5189a83820671dd8c692e9bf5e
# Parent  16c5bcc0bed4761418e938c286db1a4def2d710e
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

diff -r 16c5bcc0bed4 -r b4e26e7f964e jdk/src/java.base/share/classes/java/lang/Math.java
--- a/jdk/src/java.base/share/classes/java/lang/Math.java	Thu Sep 18 11:34:14 2014 +0200
+++ b/jdk/src/java.base/share/classes/java/lang/Math.java	Mon Sep 22 16:59:23 2014 -0700
@@ -123,6 +123,18 @@
     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.
@@ -233,7 +245,7 @@
      * @since   1.2
      */
     public static double toRadians(double angdeg) {
-        return angdeg / 180.0 * PI;
+        return angdeg * DEGREES_TO_RADIANS;
     }
 
     /**
@@ -249,7 +261,7 @@
      * @since   1.2
      */
     public static double toDegrees(double angrad) {
-        return angrad * 180.0 / PI;
+        return angrad * RADIANS_TO_DEGREES;
     }
 
     /**
diff -r 16c5bcc0bed4 -r b4e26e7f964e jdk/src/java.base/share/classes/java/lang/StrictMath.java
--- a/jdk/src/java.base/share/classes/java/lang/StrictMath.java	Thu Sep 18 11:34:14 2014 +0200
+++ b/jdk/src/java.base/share/classes/java/lang/StrictMath.java	Mon Sep 22 16:59:23 2014 -0700
@@ -98,6 +98,19 @@
     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.
@@ -179,7 +192,7 @@
     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;
+        return angdeg * DEGREES_TO_RADIANS;
     }
 
     /**
@@ -196,7 +209,7 @@
     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;
+        return angrad * RADIANS_TO_DEGREES;
     }
 
     /**