Last change
on this file since 403 was 337, checked in by coas-nagasima, 6 years ago |
ASP3版ECNLを追加
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File size:
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1 | /* origin: FreeBSD /usr/src/lib/msun/src/s_sin.c */
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2 | /*
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3 | * ====================================================
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4 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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5 | *
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6 | * Developed at SunPro, a Sun Microsystems, Inc. business.
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7 | * Permission to use, copy, modify, and distribute this
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8 | * software is freely granted, provided that this notice
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9 | * is preserved.
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10 | * ====================================================
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11 | */
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12 |
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13 | #define _GNU_SOURCE
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14 | #include "libm.h"
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15 |
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16 | void sincos(double x, double *sin, double *cos)
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17 | {
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18 | double y[2], s, c;
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19 | uint32_t ix;
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20 | unsigned n;
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21 |
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22 | GET_HIGH_WORD(ix, x);
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23 | ix &= 0x7fffffff;
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24 |
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25 | /* |x| ~< pi/4 */
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26 | if (ix <= 0x3fe921fb) {
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27 | /* if |x| < 2**-27 * sqrt(2) */
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28 | if (ix < 0x3e46a09e) {
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29 | /* raise inexact if x!=0 and underflow if subnormal */
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30 | FORCE_EVAL(ix < 0x00100000 ? x/0x1p120f : x+0x1p120f);
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31 | *sin = x;
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32 | *cos = 1.0;
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33 | return;
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34 | }
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35 | *sin = __sin(x, 0.0, 0);
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36 | *cos = __cos(x, 0.0);
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37 | return;
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38 | }
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39 |
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40 | /* sincos(Inf or NaN) is NaN */
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41 | if (ix >= 0x7ff00000) {
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42 | *sin = *cos = x - x;
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43 | return;
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44 | }
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45 |
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46 | /* argument reduction needed */
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47 | n = __rem_pio2(x, y);
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48 | s = __sin(y[0], y[1], 1);
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49 | c = __cos(y[0], y[1]);
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50 | switch (n&3) {
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51 | case 0:
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52 | *sin = s;
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53 | *cos = c;
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54 | break;
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55 | case 1:
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56 | *sin = c;
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57 | *cos = -s;
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58 | break;
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59 | case 2:
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60 | *sin = -s;
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61 | *cos = -c;
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62 | break;
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63 | case 3:
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64 | default:
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65 | *sin = -c;
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66 | *cos = s;
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67 | break;
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68 | }
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69 | }
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