87 lines
2.0 KiB
C
87 lines
2.0 KiB
C
/****************************************************************
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The author of this software is David M. Gay.
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Copyright (C) 1998 by Lucent Technologies
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All Rights Reserved
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Permission to use, copy, modify, and distribute this software and
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its documentation for any purpose and without fee is hereby
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granted, provided that the above copyright notice appear in all
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copies and that both that the copyright notice and this
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permission notice and warranty disclaimer appear in supporting
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documentation, and that the name of Lucent or any of its entities
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not be used in advertising or publicity pertaining to
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distribution of the software without specific, written prior
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permission.
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LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
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INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
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IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
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SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
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IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
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ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
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THIS SOFTWARE.
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****************************************************************/
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/* Please send bug reports to David M. Gay (dmg at acm dot org,
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* with " at " changed at "@" and " dot " changed to "."). */
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#include "gdtoaimp.h"
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void
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#ifdef KR_headers
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rshift(b, k) Bigint *b; int k;
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#else
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rshift(Bigint *b, int k)
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#endif
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{
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ULong *x, *x1, *xe, y;
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int n;
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x = x1 = b->x;
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n = k >> kshift;
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if (n < b->wds) {
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xe = x + b->wds;
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x += n;
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if (k &= kmask) {
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n = ULbits - k;
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y = *x++ >> k;
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while(x < xe) {
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*x1++ = (y | (*x << n)) & ALL_ON;
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y = *x++ >> k;
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}
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if ((*x1 = y) !=0)
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x1++;
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}
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else
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while(x < xe)
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*x1++ = *x++;
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}
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if ((b->wds = x1 - b->x) == 0)
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b->x[0] = 0;
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}
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int
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#ifdef KR_headers
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trailz(b) Bigint *b;
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#else
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trailz(Bigint *b)
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#endif
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{
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ULong L, *x, *xe;
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int n = 0;
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x = b->x;
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xe = x + b->wds;
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for(n = 0; x < xe && !*x; x++)
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n += ULbits;
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if (x < xe) {
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L = *x;
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n += lo0bits(&L);
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}
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return n;
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}
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