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Diff for /OpenXM_contrib/gmp/mpf/Attic/mul_2exp.c between version 1.1.1.1 and 1.1.1.2

version 1.1.1.1, 2000/01/10 15:35:22 version 1.1.1.2, 2000/09/09 14:13:13
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 /* mpf_mul_2exp -- Multiply a float by 2^n.  /* mpf_mul_2exp -- Multiply a float by 2^n.
   
 Copyright (C) 1993, 1994, 1996 Free Software Foundation, Inc.  Copyright (C) 1993, 1994, 1996, 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 51  mpf_mul_2exp (r, u, exp)
Line 51  mpf_mul_2exp (r, u, exp)
   abs_usize = ABS (usize);    abs_usize = ABS (usize);
   up = u->_mp_d;    up = u->_mp_d;
   
   if (abs_usize > prec)  
     {  
       up += abs_usize - prec;  
       abs_usize = prec;  
     }  
   
   if (exp % BITS_PER_MP_LIMB == 0)    if (exp % BITS_PER_MP_LIMB == 0)
     {      {
         prec++;                   /* retain more precision here as we don't need
                                      to account for carry-out here */
         if (abs_usize > prec)
           {
             up += abs_usize - prec;
             abs_usize = prec;
           }
       if (rp != up)        if (rp != up)
         MPN_COPY (rp, up, abs_usize);          MPN_COPY_INCR (rp, up, abs_usize);
       r->_mp_size = usize >= 0 ? abs_usize : -abs_usize;  
       r->_mp_exp = uexp + exp / BITS_PER_MP_LIMB;        r->_mp_exp = uexp + exp / BITS_PER_MP_LIMB;
     }      }
   else    else
     {      {
       mp_limb_t cy_limb;        mp_limb_t cy_limb;
       if (r != u)        mp_size_t adj;
         if (abs_usize > prec)
         {          {
           cy_limb = mpn_lshift (rp, up, abs_usize, exp % BITS_PER_MP_LIMB);            up += abs_usize - prec;
           rp[abs_usize] = cy_limb;            abs_usize = prec;
           cy_limb = cy_limb != 0;            /* Use mpn_rshift since mpn_lshift operates downwards, and we
                therefore would clobber part of U before using that part, in case
                R is the same variable as U.  */
             cy_limb = mpn_rshift (rp + 1, up, abs_usize, (-exp) % BITS_PER_MP_LIMB);
             rp[0] = cy_limb;
             adj = rp[abs_usize] != 0;
         }          }
       else        else
         {          {
           /* Use mpn_rshift since mpn_lshift operates downwards, and we            cy_limb = mpn_lshift (rp, up, abs_usize, exp % BITS_PER_MP_LIMB);
              therefore would clobber part of U before using that part.  */            rp[abs_usize] = cy_limb;
           cy_limb = mpn_rshift (rp + 1, up, abs_usize, -exp % BITS_PER_MP_LIMB);            adj = cy_limb != 0;
           rp[0] = cy_limb;  
           cy_limb = rp[abs_usize] != 0;  
         }          }
   
       abs_usize += cy_limb;        abs_usize += adj;
       r->_mp_size = usize >= 0 ? abs_usize : -abs_usize;        r->_mp_exp = uexp + exp / BITS_PER_MP_LIMB + adj;
       r->_mp_exp = uexp + exp / BITS_PER_MP_LIMB + cy_limb;  
     }      }
     r->_mp_size = usize >= 0 ? abs_usize : -abs_usize;
 }  }
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  Added in v.1.1.1.2
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