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/* s_tanf.c -- float version of s_tan.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.
* ====================================================
*/
#ifndef lint
static char rcsid[] = "$Id: s_tanf.c,v 1.1.1.1 1994/08/19 09:39:58 jkh Exp $";
#endif
#include "math.h"
#include "math_private.h"
#ifdef __STDC__
float tanf(float x)
#else
float tanf(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 <= 0x3f490fda) return __kernel_tanf(x,z,1);
/* tan(Inf or NaN) is NaN */
else if (ix>=0x7f800000) return x-x; /* NaN */
/* argument reduction needed */
else {
n = __ieee754_rem_pio2f(x,y);
return __kernel_tanf(y[0],y[1],1-((n&1)<<1)); /* 1 -- n even
-1 -- n odd */
}
}
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