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Diff for /OpenXM_contrib/gmp/mpn/generic/Attic/bdivmod.c between version 1.1.1.1 and 1.1.1.2

version 1.1.1.1, 2000/01/10 15:35:23 version 1.1.1.2, 2000/09/09 14:12:24
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 /* mpn/bdivmod.c: mpn_bdivmod for computing U/V mod 2^d.  /* mpn/bdivmod.c: mpn_bdivmod for computing U/V mod 2^d.
   
 Copyright (C) 1991, 1993, 1994, 1995, 1996 Free Software Foundation, Inc.  Copyright (C) 1991, 1993, 1994, 1995, 1996, 1999, 2000 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 65  mpn_bdivmod (qp, up, usize, vp, vsize, d)
Line 66  mpn_bdivmod (qp, up, usize, vp, vsize, d)
      unsigned long int d;       unsigned long int d;
 #endif  #endif
 {  {
   /* Cache for v_inv is used to make mpn_accelgcd faster.  */    mp_limb_t v_inv;
   static mp_limb_t previous_low_vlimb = 0;  
   static mp_limb_t v_inv;               /* 1/V mod 2^BITS_PER_MP_LIMB.  */  
   
   if (vp[0] != previous_low_vlimb)      /* Cache miss; compute v_inv.  */    /* 1/V mod 2^BITS_PER_MP_LIMB. */
     {    modlimb_invert (v_inv, vp[0]);
       mp_limb_t v = previous_low_vlimb = vp[0];  
       mp_limb_t make_zero = 1;  
       mp_limb_t two_i = 1;  
       v_inv = 0;  
       do  
         {  
           while ((two_i & make_zero) == 0)  
             two_i <<= 1, v <<= 1;  
           v_inv += two_i;  
           make_zero -= v;  
         }  
       while (make_zero);  
     }  
   
   /* Need faster computation for some common cases in mpn_accelgcd.  */    /* Fast code for two cases previously used by the accel part of mpn_gcd.
        (Could probably remove this now it's inlined there.) */
   if (usize == 2 && vsize == 2 &&    if (usize == 2 && vsize == 2 &&
       (d == BITS_PER_MP_LIMB || d == 2*BITS_PER_MP_LIMB))        (d == BITS_PER_MP_LIMB || d == 2*BITS_PER_MP_LIMB))
     {      {
Line 114  mpn_bdivmod (qp, up, usize, vp, vsize, d)
Line 101  mpn_bdivmod (qp, up, usize, vp, vsize, d)
     {      {
       mp_limb_t b;        mp_limb_t b;
       mp_limb_t q = (up[0] * v_inv) & (((mp_limb_t)1<<d) - 1);        mp_limb_t q = (up[0] * v_inv) & (((mp_limb_t)1<<d) - 1);
       switch (q)        if (q <= 1)
         {          {
           case 0:  return 0;            if (q == 0)
           case 1:  b = mpn_sub_n (up, up, vp, MIN (usize, vsize));   break;              return 0;
           default: b = mpn_submul_1 (up, vp, MIN (usize, vsize), q); break;            else
               b = mpn_sub_n (up, up, vp, MIN (usize, vsize));
         }          }
         else
           b = mpn_submul_1 (up, vp, MIN (usize, vsize), q);
   
       if (usize > vsize)        if (usize > vsize)
         mpn_sub_1 (up + vsize, up + vsize, usize - vsize, b);          mpn_sub_1 (up + vsize, up + vsize, usize - vsize, b);
       return q;        return q;
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Removed from v.1.1.1.1  
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  Added in v.1.1.1.2
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