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/* sf_cos.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 "fdlibm.h"
#ifdef __STDC__
static const float one=1.0;
#else
static float one=1.0;
#endif
#ifdef __STDC__
float cosf(float x)
#else
float cosf(x)
float x;
#endif
{
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 (!FLT_UWORD_IS_FINITE(ix)) 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);
}
}
}
#ifdef _DOUBLE_IS_32BITS
#ifdef __STDC__
double cos(double x)
#else
double cos(x)
double x;
#endif
{
return (double) cosf((float) x);
}
#endif /* defined(_DOUBLE_IS_32BITS) */
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