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/* s_tanf.c -- float version of s_tan.c.
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 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
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 */
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/*
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 * ====================================================
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 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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 *
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 * Developed at SunPro, a Sun Microsystems, Inc. business.
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 * Permission to use, copy, modify, and distribute this
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 * software is freely granted, provided that this notice
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 * is preserved.
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 * ====================================================
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 */
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#ifndef lint
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static char rcsid[] = "$\Id: s_tanf.c,v 1.2 1995/05/30 05:50:34 rgrimes Exp $";
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#endif
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#include "math.h"
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#include "math_private.h"
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#ifdef __STDC__
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        float tanf(float x)
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#else
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        float tanf(x)
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        float x;
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#endif
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{
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        float y[2],z=0.0;
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        int32_t n, ix;
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        GET_FLOAT_WORD(ix,x);
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    /* |x| ~< pi/4 */
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        ix &= 0x7fffffff;
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        if(ix <= 0x3f490fda) return __kernel_tanf(x,z,1);
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    /* tan(Inf or NaN) is NaN */
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        else if (ix>=0x7f800000) return x-x;            /* NaN */
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    /* argument reduction needed */
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        else {
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            n = __ieee754_rem_pio2f(x,y);
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            return __kernel_tanf(y[0],y[1],1-((n&1)<<1)); /*   1 -- n even
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                                                              -1 -- n odd */
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        }
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}