1 | /* $NetBSD: gmisc.c,v 1.3 2006/03/11 18:38:14 kleink Exp $ */
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2 |
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3 | /****************************************************************
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4 |
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5 | The author of this software is David M. Gay.
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6 |
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7 | Copyright (C) 1998 by Lucent Technologies
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8 | All Rights Reserved
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9 |
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10 | Permission to use, copy, modify, and distribute this software and
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11 | its documentation for any purpose and without fee is hereby
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12 | granted, provided that the above copyright notice appear in all
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13 | copies and that both that the copyright notice and this
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14 | permission notice and warranty disclaimer appear in supporting
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15 | documentation, and that the name of Lucent or any of its entities
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16 | not be used in advertising or publicity pertaining to
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17 | distribution of the software without specific, written prior
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18 | permission.
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19 |
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20 | LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
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21 | INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
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22 | IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
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23 | SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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24 | WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
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25 | IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
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26 | ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
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27 | THIS SOFTWARE.
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28 |
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29 | ****************************************************************/
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30 |
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31 | /* Please send bug reports to David M. Gay (dmg at acm dot org,
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32 | * with " at " changed at "@" and " dot " changed to "."). */
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33 | #include <LibConfig.h>
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34 |
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35 | #include "gdtoaimp.h"
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36 |
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37 | void
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38 | rshift(Bigint *b, int k)
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39 | {
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40 | ULong *x, *x1, *xe, y;
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41 | int n;
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42 |
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43 | x = x1 = b->x;
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44 | n = (unsigned int)k >> kshift;
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45 | if (n < b->wds) {
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46 | xe = x + b->wds;
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47 | x += n;
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48 | if (k &= kmask) {
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49 | n = ULbits - k;
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50 | y = *x++ >> k;
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51 | while(x < xe) {
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52 | *x1++ = (y | (*x << n)) & ALL_ON;
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53 | y = *x++ >> k;
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54 | }
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55 | if ((*x1 = y) !=0)
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56 | x1++;
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57 | }
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58 | else
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59 | while(x < xe)
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60 | *x1++ = *x++;
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61 | }
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62 | if ((b->wds = (int)(x1 - b->x)) == 0)
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63 | b->x[0] = 0;
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64 | }
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65 |
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66 | int
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67 | trailz(CONST Bigint *b)
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68 | {
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69 | ULong L;
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70 | CONST ULong *x, *xe;
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71 | int n = 0;
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72 |
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73 | x = b->x;
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74 | xe = x + b->wds;
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75 | for(n = 0; x < xe && !*x; x++)
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76 | n += ULbits;
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77 | if (x < xe) {
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78 | L = *x;
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79 | n += lo0bits(&L);
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80 | }
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81 | return n;
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82 | }
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