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-rw-r--r--libm/src/s_cos.c82
1 files changed, 0 insertions, 82 deletions
diff --git a/libm/src/s_cos.c b/libm/src/s_cos.c
deleted file mode 100644
index 0faf91e..0000000
--- a/libm/src/s_cos.c
+++ /dev/null
@@ -1,82 +0,0 @@
-/* @(#)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.
- * ====================================================
- */
-
-#ifndef lint
-static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_cos.c,v 1.10 2005/10/24 14:08:36 bde 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"
-
-double
-cos(double x)
-{
- 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) {
- if(ix<0x3e400000) /* if x < 2**-27 */
- if(((int)x)==0) return 1.0; /* generate inexact */
- 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);
- }
- }
-}