vx32

Local 9vx git repository for patches.
git clone git://r-36.net/vx32
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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 }