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Diff for /OpenXM_contrib/gmp/mpn/generic/Attic/sub_n.c between version 1.1.1.2 and 1.1.1.3

version 1.1.1.2, 2000/09/09 14:12:27 version 1.1.1.3, 2003/08/25 16:06:20
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 /* mpn_sub_n -- Subtract two limb vectors of equal, non-zero length.  /* mpn_sub_n -- Subtract equal length limb vectors.
   
 Copyright (C) 1992, 1993, 1994, 1996 Free Software Foundation, Inc.  Copyright 1992, 1993, 1994, 1996, 2000, 2002 Free Software Foundation, Inc.
   
 This file is part of the GNU MP Library.  This file is part of the GNU MP Library.
   
Line 22  MA 02111-1307, USA. */
Line 22  MA 02111-1307, USA. */
 #include "gmp.h"  #include "gmp.h"
 #include "gmp-impl.h"  #include "gmp-impl.h"
   
   
   #if GMP_NAIL_BITS == 0
   
 mp_limb_t  mp_limb_t
 #if __STDC__  mpn_sub_n (mp_ptr rp, mp_srcptr up, mp_srcptr vp, mp_size_t n)
 mpn_sub_n (mp_ptr res_ptr, mp_srcptr s1_ptr, mp_srcptr s2_ptr, mp_size_t size)  
 #else  
 mpn_sub_n (res_ptr, s1_ptr, s2_ptr, size)  
      register mp_ptr res_ptr;  
      register mp_srcptr s1_ptr;  
      register mp_srcptr s2_ptr;  
      mp_size_t size;  
 #endif  
 {  {
   register mp_limb_t x, y, cy;    mp_limb_t ul, vl, sl, rl, cy, cy1, cy2;
   register mp_size_t j;  
   
   /* The loop counter and index J goes from -SIZE to -1.  This way    ASSERT (n >= 1);
      the loop becomes faster.  */    ASSERT (MPN_SAME_OR_SEPARATE_P (rp, up, n));
   j = -size;    ASSERT (MPN_SAME_OR_SEPARATE_P (rp, vp, n));
   
   /* Offset the base pointers to compensate for the negative indices.  */    cy = 0;
   s1_ptr -= j;    do
   s2_ptr -= j;      {
   res_ptr -= j;        ul = *up++;
         vl = *vp++;
         sl = ul - vl;
         cy1 = sl > ul;
         rl = sl - cy;
         cy2 = rl > sl;
         cy = cy1 | cy2;
         *rp++ = rl;
       }
     while (--n != 0);
   
     return cy;
   }
   
   #endif
   
   #if GMP_NAIL_BITS >= 1
   
   mp_limb_t
   mpn_sub_n (mp_ptr rp, mp_srcptr up, mp_srcptr vp, mp_size_t n)
   {
     mp_limb_t ul, vl, rl, cy;
   
     ASSERT (n >= 1);
     ASSERT (MPN_SAME_OR_SEPARATE_P (rp, up, n));
     ASSERT (MPN_SAME_OR_SEPARATE_P (rp, vp, n));
   
   cy = 0;    cy = 0;
   do    do
     {      {
       y = s2_ptr[j];        ul = *up++;
       x = s1_ptr[j];        vl = *vp++;
       y += cy;                  /* add previous carry to subtrahend */        rl = ul - vl - cy;
       cy = (y < cy);            /* get out carry from that addition */        cy = rl >> (GMP_LIMB_BITS - 1);
       y = x - y;                /* main subtract */        *rp++ = rl & GMP_NUMB_MASK;
       cy = (y > x) + cy;        /* get out carry from the subtract, combine */  
       res_ptr[j] = y;  
     }      }
   while (++j != 0);    while (--n != 0);
   
   return cy;    return cy;
 }  }
   
   #endif

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