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-rw-r--r--sysdeps/ieee754/dbl-64/s_cos.c88
1 files changed, 1 insertions, 87 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_cos.c b/sysdeps/ieee754/dbl-64/s_cos.c
index 7edb5deafe..4be1276ccb 100644
--- a/sysdeps/ieee754/dbl-64/s_cos.c
+++ b/sysdeps/ieee754/dbl-64/s_cos.c
@@ -1,87 +1 @@
-/* @(#)s_cos.c 5.1 93/09/24 */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunPro, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice
- * is preserved.
- * ====================================================
- */
-
-#if defined(LIBM_SCCS) && !defined(lint)
-static char rcsid[] = "$NetBSD: s_cos.c,v 1.7 1995/05/10 20:47:02 jtc Exp $";
-#endif
-
-/* cos(x)
- * Return cosine function of x.
- *
- * kernel function:
- *	__kernel_sin		... sine function on [-pi/4,pi/4]
- *	__kernel_cos		... cosine function on [-pi/4,pi/4]
- *	__ieee754_rem_pio2	... 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
- *
- *          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
- *     ----------------------------------------------------------
- *
- * Special cases:
- *      Let trig be any of sin, cos, or tan.
- *      trig(+-INF)  is NaN, with signals;
- *      trig(NaN)    is that NaN;
- *
- * Accuracy:
- *	TRIG(x) returns trig(x) nearly rounded
- */
-
-#include "math.h"
-#include "math_private.h"
-
-#ifdef __STDC__
-	double __cos(double x)
-#else
-	double __cos(x)
-	double x;
-#endif
-{
-	double y[2],z=0.0;
-	int32_t n, ix;
-
-    /* High word of x. */
-	GET_HIGH_WORD(ix,x);
-
-    /* |x| ~< pi/4 */
-	ix &= 0x7fffffff;
-	if(ix <= 0x3fe921fb) return __kernel_cos(x,z);
-
-    /* cos(Inf or NaN) is NaN */
-	else if (ix>=0x7ff00000) return x-x;
-
-    /* argument reduction needed */
-	else {
-	    n = __ieee754_rem_pio2(x,y);
-	    switch(n&3) {
-		case 0: return  __kernel_cos(y[0],y[1]);
-		case 1: return -__kernel_sin(y[0],y[1],1);
-		case 2: return -__kernel_cos(y[0],y[1]);
-		default:
-		        return  __kernel_sin(y[0],y[1],1);
-	    }
-	}
-}
-weak_alias (__cos, cos)
-#ifdef NO_LONG_DOUBLE
-strong_alias (__cos, __cosl)
-weak_alias (__cos, cosl)
-#endif
+/* In s_sin.c.  */