File: [local] / OpenXM / src / kan96xx / gmp-2.0.2-ssh-2 / mpn / generic / Attic / hamdist.c (download)
Revision 1.1.1.1 (vendor branch), Mon Oct 25 08:53:35 1999 UTC (24 years, 10 months ago) by takayama
Branch: TAKAYAMA
CVS Tags: RELEASE_20000124, RELEASE_1_1_2, GMP_2_0_2_SSH_2 Changes since 1.1: +0 -0
lines
gmp-2.0.2-ssh-2 is added.
It is a patched version of gmp-2.0.2 to compile on FreeBSD 3.3.
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/* mpn_hamdist --
Copyright (C) 1994, 1996 Free Software Foundation, Inc.
This file is part of the GNU MP Library.
The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
The GNU MP Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
License for more details.
You should have received a copy of the GNU Library General Public License
along with the GNU MP Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include "gmp.h"
#include "gmp-impl.h"
#if defined __GNUC__
#if defined __sparc_v9__ && BITS_PER_MP_LIMB == 64
#define popc_limb(a) \
({ \
DItype __res; \
asm ("popc %1,%0" : "=r" (__res) : "rI" (a)); \
__res; \
})
#endif
#endif
#ifndef popc_limb
/* Cool population count of a mp_limb_t.
You have to figure out how this works, I won't tell you! */
static inline unsigned int
popc_limb (x)
mp_limb_t x;
{
#if BITS_PER_MP_LIMB == 64
/* We have to go into some trouble to define these constants.
(For mp_limb_t being `long long'.) */
mp_limb_t cnst;
cnst = 0x55555555L | ((mp_limb_t) 0x55555555L << BITS_PER_MP_LIMB/2);
x = ((x & ~cnst) >> 1) + (x & cnst);
cnst = 0x33333333L | ((mp_limb_t) 0x33333333L << BITS_PER_MP_LIMB/2);
x = ((x & ~cnst) >> 2) + (x & cnst);
cnst = 0x0f0f0f0fL | ((mp_limb_t) 0x0f0f0f0fL << BITS_PER_MP_LIMB/2);
x = ((x >> 4) + x) & cnst;
x = ((x >> 8) + x);
x = ((x >> 16) + x);
x = ((x >> 32) + x) & 0xff;
#endif
#if BITS_PER_MP_LIMB == 32
x = ((x >> 1) & 0x55555555L) + (x & 0x55555555L);
x = ((x >> 2) & 0x33333333L) + (x & 0x33333333L);
x = ((x >> 4) + x) & 0x0f0f0f0fL;
x = ((x >> 8) + x);
x = ((x >> 16) + x) & 0xff;
#endif
return x;
}
#endif
unsigned long int
#if __STDC__
mpn_hamdist (mp_srcptr up, mp_srcptr vp, mp_size_t size)
#else
mpn_hamdist (up, vp, size)
register mp_srcptr up;
register mp_srcptr vp;
register mp_size_t size;
#endif
{
unsigned long int hamdist;
mp_size_t i;
hamdist = 0;
for (i = 0; i < size; i++)
hamdist += popc_limb (up[i] ^ vp[i]);
return hamdist;
}