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/* k_cosf.c -- float version of k_cos.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: k_cosf.c,v 1.2 1995/05/30 05:48:55 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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static const float
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#else
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static float
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#endif
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one =  1.0000000000e+00, /* 0x3f800000 */
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C1  =  4.1666667908e-02, /* 0x3d2aaaab */
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C2  = -1.3888889225e-03, /* 0xbab60b61 */
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C3  =  2.4801587642e-05, /* 0x37d00d01 */
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C4  = -2.7557314297e-07, /* 0xb493f27c */
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C5  =  2.0875723372e-09, /* 0x310f74f6 */
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C6  = -1.1359647598e-11; /* 0xad47d74e */
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#ifdef __STDC__
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        float __kernel_cosf(float x, float y)
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#else
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        float __kernel_cosf(x, y)
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        float x,y;
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#endif
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{
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        float a,hz,z,r,qx;
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        int32_t ix;
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        GET_FLOAT_WORD(ix,x);
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        ix &= 0x7fffffff;                       /* ix = |x|'s high word*/
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        if(ix<0x32000000) {                     /* if x < 2**27 */
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            if(((int)x)==0) return one;         /* generate inexact */
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        }
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        z  = x*x;
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        r  = z*(C1+z*(C2+z*(C3+z*(C4+z*(C5+z*C6)))));
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        if(ix < 0x3e99999a)                     /* if |x| < 0.3 */
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            return one - ((float)0.5*z - (z*r - x*y));
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        else {
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            if(ix > 0x3f480000) {               /* x > 0.78125 */
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                qx = (float)0.28125;
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            } else {
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                SET_FLOAT_WORD(qx,ix-0x01000000);       /* x/4 */
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            }
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            hz = (float)0.5*z-qx;
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            a  = one-qx;
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            return a - (hz - (z*r-x*y));
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        }
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}