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Diff for /OpenXM_contrib/gmp/mpz/Attic/hamdist.c between version 1.1 and 1.1.1.3

version 1.1, 2000/01/10 15:35:27 version 1.1.1.3, 2003/08/25 16:06:33
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 /* mpz_hamdist(mpz_ptr op1, mpz_ptr op2) -- Compute the hamming distance  /* mpz_hamdist -- calculate hamming distance.
    between OP1 and OP2.  If one of the operands is negative, return ~0.  (We  
    could make the function well-defined when both operands are negative, but  
    that would probably not be worth the trouble.  
   
 Copyright (C) 1994, 1996 Free Software Foundation, Inc.  Copyright 1994, 1996, 2001, 2002 Free Software Foundation, Inc.
   
 This file is part of the GNU MP Library.  This file is part of the GNU MP Library.
   
 The GNU MP Library is free software; you can redistribute it and/or modify  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  it under the terms of the GNU Lesser General Public License as published by
 the Free Software Foundation; either version 2 of the License, or (at your  the Free Software Foundation; either version 2.1 of the License, or (at your
 option) any later version.  option) any later version.
   
 The GNU MP Library is distributed in the hope that it will be useful, but  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  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
 License for more details.  License for more details.
   
 You should have received a copy of the GNU Library General Public License  You should have received a copy of the GNU Lesser General Public License
 along with the GNU MP Library; see the file COPYING.LIB.  If not, write to  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,  the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 MA 02111-1307, USA. */  MA 02111-1307, USA. */
Line 25  MA 02111-1307, USA. */
Line 22  MA 02111-1307, USA. */
 #include "gmp.h"  #include "gmp.h"
 #include "gmp-impl.h"  #include "gmp-impl.h"
   
 unsigned long int  
 #if __STDC__  unsigned long
 mpz_hamdist (mpz_srcptr u, mpz_srcptr v)  mpz_hamdist (mpz_srcptr u, mpz_srcptr v)
 #else  
 mpz_hamdist (u, v)  
      mpz_srcptr u;  
      mpz_srcptr v;  
 #endif  
 {  {
   mp_srcptr up, vp;    mp_srcptr      up, vp;
   mp_size_t usize, vsize, size;    mp_size_t      usize, vsize;
   unsigned long int count;    unsigned long  count;
   
   usize = u->_mp_size;    usize = SIZ(u);
   vsize = v->_mp_size;    vsize = SIZ(v);
   
   if ((usize | vsize) < 0)    up = PTR(u);
     return ~ (unsigned long int) 0;    vp = PTR(v);
   
   up = u->_mp_d;    if (usize >= 0)
   vp = v->_mp_d;  
   
   if (usize > vsize)  
     {      {
       count = mpn_popcount (up + vsize, usize - vsize);        if (vsize < 0)
       size = vsize;          return ~ (unsigned long) 0;
   
         /* positive/positive */
   
         if (usize < vsize)
           MPN_SRCPTR_SWAP (up,usize, vp,vsize);
   
         count = 0;
         if (vsize != 0)
           count = mpn_hamdist (up, vp, vsize);
   
         usize -= vsize;
         if (usize != 0)
           count += mpn_popcount (up + vsize, usize);
   
         return count;
     }      }
   else    else
     {      {
       count = mpn_popcount (vp + usize, vsize - usize);        mp_limb_t  ulimb, vlimb;
       size = usize;        mp_size_t  old_vsize, step;
     }  
   
   return count + mpn_hamdist (up, vp, size);        if (vsize >= 0)
           return ~ (unsigned long) 0;
   
         /* negative/negative */
   
         usize = -usize;
         vsize = -vsize;
   
         /* skip common low zeros */
         for (;;)
           {
             ASSERT (usize > 0);
             ASSERT (vsize > 0);
   
             usize--;
             vsize--;
   
             ulimb = *up++;
             vlimb = *vp++;
   
             if (ulimb != 0)
               break;
   
             if (vlimb != 0)
               {
                 MPN_SRCPTR_SWAP (up,usize, vp,vsize);
                 ulimb = vlimb;
                 vlimb = 0;
                 break;
               }
           }
   
         /* twos complement first non-zero limbs (ulimb is non-zero, but vlimb
            might be zero) */
         ulimb = -ulimb;
         vlimb = -vlimb;
         popc_limb (count, (ulimb ^ vlimb) & GMP_NUMB_MASK);
   
         if (vlimb == 0)
           {
             unsigned long  twoscount;
   
             /* first non-zero of v */
             old_vsize = vsize;
             do
               {
                 ASSERT (vsize > 0);
                 vsize--;
                 vlimb = *vp++;
               }
             while (vlimb == 0);
   
             /* part of u corresponding to skipped v zeros */
             step = old_vsize - vsize - 1;
             count += step * GMP_NUMB_BITS;
             step = MIN (step, usize);
             if (step != 0)
               {
                 count -= mpn_popcount (up, step);
                 usize -= step;
                 up += step;
               }
   
             /* First non-zero vlimb as twos complement, xor with ones
                complement ulimb.  Note -v^(~0^u) == (v-1)^u. */
             vlimb--;
             if (usize != 0)
               {
                 usize--;
                 vlimb ^= *up++;
               }
             popc_limb (twoscount, vlimb);
             count += twoscount;
           }
   
         /* Overlapping part of u and v, if any.  Ones complement both, so just
            plain hamdist. */
         step = MIN (usize, vsize);
         if (step != 0)
           {
             count += mpn_hamdist (up, vp, step);
             usize -= step;
             vsize -= step;
             up += step;
             vp += step;
           }
   
         /* Remaining high part of u or v, if any, ones complement but xor
            against all ones in the other, so plain popcount. */
         if (usize != 0)
           {
           remaining:
             count += mpn_popcount (up, usize);
           }
         else if (vsize != 0)
           {
             up = vp;
             usize = vsize;
             goto remaining;
           }
         return count;
       }
 }  }
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  Added in v.1.1.1.3
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