1 | /* kf_sin.c -- float version of k_sin.c |
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2 | * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
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3 | */ |
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4 | |
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5 | /* |
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6 | * ==================================================== |
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7 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
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8 | * |
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9 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
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10 | * Permission to use, copy, modify, and distribute this |
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11 | * software is freely granted, provided that this notice |
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12 | * is preserved. |
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13 | * ==================================================== |
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14 | */ |
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15 | |
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16 | #include "fdlibm.h" |
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17 | |
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18 | #ifdef __STDC__ |
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19 | static const float |
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20 | #else |
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21 | static float |
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22 | #endif |
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23 | half = 5.0000000000e-01,/* 0x3f000000 */ |
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24 | S1 = -1.6666667163e-01, /* 0xbe2aaaab */ |
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25 | S2 = 8.3333337680e-03, /* 0x3c088889 */ |
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26 | S3 = -1.9841270114e-04, /* 0xb9500d01 */ |
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27 | S4 = 2.7557314297e-06, /* 0x3638ef1b */ |
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28 | S5 = -2.5050759689e-08, /* 0xb2d72f34 */ |
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29 | S6 = 1.5896910177e-10; /* 0x2f2ec9d3 */ |
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30 | |
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31 | #ifdef __STDC__ |
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32 | float __kernel_sinf(float x, float y, int iy) |
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33 | #else |
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34 | float __kernel_sinf(x, y, iy) |
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35 | float x,y; int iy; /* iy=0 if y is zero */ |
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36 | #endif |
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37 | { |
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38 | float z,r,v; |
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39 | __int32_t ix; |
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40 | GET_FLOAT_WORD(ix,x); |
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41 | ix &= 0x7fffffff; /* high word of x */ |
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42 | if(ix<0x32000000) /* |x| < 2**-27 */ |
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43 | {if((int)x==0) return x;} /* generate inexact */ |
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44 | z = x*x; |
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45 | v = z*x; |
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46 | r = S2+z*(S3+z*(S4+z*(S5+z*S6))); |
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47 | if(iy==0) return x+v*(S1+z*r); |
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48 | else return x-((z*(half*y-v*r)-y)-v*S1); |
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49 | } |
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