mirror of
https://gitlab.com/sortix/sortix.git
synced 2023-02-13 20:55:38 -05:00
62 lines
1.3 KiB
C
62 lines
1.3 KiB
C
|
/* s_cosf.c -- float version of s_cos.c.
|
||
|
|
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/*
|
||
|
|
* ====================================================
|
||
|
|
* 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.
|
||
|
|
* ====================================================
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <sys/cdefs.h>
|
||
|
|
#if defined(LIBM_SCCS) && !defined(lint)
|
||
|
|
__RCSID("$NetBSD: s_cosf.c,v 1.9 2007/08/20 16:01:39 drochner Exp $");
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#include "namespace.h"
|
||
|
|
#include "math.h"
|
||
|
|
#include "math_private.h"
|
||
|
|
|
||
|
|
#if 0 /* notyet */
|
||
|
|
#ifdef __weak_alias
|
||
|
|
__weak_alias(cosf, _cosf)
|
||
|
|
#endif
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#if 0
|
||
|
|
static const float one=1.0;
|
||
|
|
#endif
|
||
|
|
|
||
|
|
float
|
||
|
|
cosf(float x)
|
||
|
|
{
|
||
|
|
float y[2],z=0.0;
|
||
|
|
int32_t n,ix;
|
||
|
|
|
||
|
|
GET_FLOAT_WORD(ix,x);
|
||
|
|
|
||
|
|
/* |x| ~< pi/4 */
|
||
|
|
ix &= 0x7fffffff;
|
||
|
|
if(ix <= 0x3f490fd8) return __kernel_cosf(x,z);
|
||
|
|
|
||
|
|
/* cos(Inf or NaN) is NaN */
|
||
|
|
else if (ix>=0x7f800000) return x-x;
|
||
|
|
|
||
|
|
/* argument reduction needed */
|
||
|
|
else {
|
||
|
|
n = __ieee754_rem_pio2f(x,y);
|
||
|
|
switch(n&3) {
|
||
|
|
case 0: return __kernel_cosf(y[0],y[1]);
|
||
|
|
case 1: return -__kernel_sinf(y[0],y[1],1);
|
||
|
|
case 2: return -__kernel_cosf(y[0],y[1]);
|
||
|
|
default:
|
||
|
|
return __kernel_sinf(y[0],y[1],1);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|