s_cosf.c - vx32 - Local 9vx git repository for patches.
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       ---
       s_cosf.c (1243B)
       ---
            1 /* s_cosf.c -- float version of s_cos.c.
            2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
            3  */
            4 
            5 /*
            6  * ====================================================
            7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
            8  *
            9  * Developed at SunPro, a Sun Microsystems, Inc. business.
           10  * Permission to use, copy, modify, and distribute this
           11  * software is freely granted, provided that this notice
           12  * is preserved.
           13  * ====================================================
           14  */
           15 
           16 #ifndef lint
           17 static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_cosf.c,v 1.7 2002/05/28 18:15:04 alfred Exp $";
           18 #endif
           19 
           20 #include "math.h"
           21 #include "math_private.h"
           22 
           23 static const float one=1.0;
           24 
           25 float
           26 cosf(float x)
           27 {
           28         float y[2],z=0.0;
           29         int32_t n,ix;
           30 
           31         GET_FLOAT_WORD(ix,x);
           32 
           33     /* |x| ~< pi/4 */
           34         ix &= 0x7fffffff;
           35         if(ix <= 0x3f490fd8) return __kernel_cosf(x,z);
           36 
           37     /* cos(Inf or NaN) is NaN */
           38         else if (ix>=0x7f800000) return x-x;
           39 
           40     /* argument reduction needed */
           41         else {
           42             n = __ieee754_rem_pio2f(x,y);
           43             switch(n&3) {
           44                 case 0: return  __kernel_cosf(y[0],y[1]);
           45                 case 1: return -__kernel_sinf(y[0],y[1],1);
           46                 case 2: return -__kernel_cosf(y[0],y[1]);
           47                 default:
           48                         return  __kernel_sinf(y[0],y[1],1);
           49             }
           50         }
           51 }