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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[] = "$FreeBSD$";
#endif
#include "math.h"
#include "math_private.h"
float
tanf(float x)
{
float y[2];
int32_t n, ix;
GET_FLOAT_WORD(ix,x);
ix &= 0x7fffffff;
if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */
if(ix<0x39800000) /* |x| < 2**-12 */
if(((int)x)==0) return x; /* x with inexact if x != 0 */
return __kernel_tanf(x,0.0,1);
}
/* tan(Inf or NaN) is NaN */
else if (ix>=0x7f800000) return x-x;
/* argument reduction needed */
else {
n = __ieee754_rem_pio2f(x,y);
/* integer parameter: 1 -- n even; -1 -- n odd */
return __kernel_tanf(y[0],y[1],1-((n&1)<<1));
}
}
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