X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fcosl.c;h=53df794a1e28f9d1f7fdf5c02e63155f36581dcd;hb=fe36c7a0984ab97b84f3909cd1d2be5e91706515;hp=3c28f77c6db93ad510b0580ac689ab26151685f0;hpb=e1123c2f4fedae90435426a82a05cf2e3233e97d;p=gnulib.git

diff --git a/lib/cosl.c b/lib/cosl.c
index 3c28f77c6..53df794a1 100644
--- a/lib/cosl.c
+++ b/lib/cosl.c
@@ -22,22 +22,22 @@
  * Return sine function of x.
  *
  * kernel function:
- *	__kernel_sinl		... sine function on [-pi/4,pi/4]
- *	__kernel_cosl		... cose function on [-pi/4,pi/4]
- *	__ieee754_rem_pio2l	... argument reduction routine
+ *      __kernel_sinl           ... sine function on [-pi/4,pi/4]
+ *      __kernel_cosl           ... cose function on [-pi/4,pi/4]
+ *      __ieee754_rem_pio2l     ... argument reduction routine
  *
  * Method.
  *      Let S,C and T denote the sin, cos and tan respectively on
- *	[-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
- *	in [-pi/4 , +pi/4], and let n = k mod 4.
- *	We have
+ *      [-PI/4, +PI/4]. Reduce the argument x to y1+y2 = x-k*pi/2
+ *      in [-pi/4 , +pi/4], and let n = k mod 4.
+ *      We have
  *
  *          n        sin(x)      cos(x)        tan(x)
  *     ----------------------------------------------------------
- *	    0	       S	   C		 T
- *	    1	       C	  -S		-1/T
- *	    2	      -S	  -C		 T
- *	    3	      -C	   S		-1/T
+ *          0          S           C             T
+ *          1          C          -S            -1/T
+ *          2         -S          -C             T
+ *          3         -C           S            -1/T
  *     ----------------------------------------------------------
  *
  * Special cases:
@@ -46,7 +46,7 @@
  *      trig(NaN)    is that NaN;
  *
  * Accuracy:
- *	TRIG(x) returns trig(x) nearly rounded
+ *      TRIG(x) returns trig(x) nearly rounded
  */
 
 #include "trigl.h"
@@ -57,29 +57,33 @@
 
 long double cosl(long double x)
 {
-	long double y[2],z=0.0L;
-	int n;
+        long double y[2],z=0.0L;
+        int n;
+
+    /* cosl(NaN) is NaN */
+        if (isnanl (x))
+          return x;
 
     /* |x| ~< pi/4 */
         if(x >= -0.7853981633974483096156608458198757210492 &&
            x <= 0.7853981633974483096156608458198757210492)
           return kernel_cosl(x, z);
 
-    /* sinl(Inf or NaN) is NaN, sinl(0) is 0 */
-        else if ((x + x == x && x != 0.0) || x != x)
+    /* cosl(Inf) is NaN, cosl(0) is 1 */
+        else if (x + x == x && x != 0.0)
           return x-x;           /* NaN */
 
     /* argument reduction needed */
-	else {
-	    n = ieee754_rem_pio2l(x,y);
+        else {
+            n = ieee754_rem_pio2l(x,y);
             switch(n&3) {
                 case 0: return  kernel_cosl(y[0],y[1]);
                 case 1: return -kernel_sinl(y[0],y[1],1);
                 case 2: return -kernel_cosl(y[0],y[1]);
                 default:
                         return  kernel_sinl(y[0],y[1],1);
-	    }
-	}
+            }
+        }
 }
 
 #if 0