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Diff for /OpenXM_contrib/gmp/mpz/Attic/tdiv_q.c between version 1.1.1.1 and 1.1.1.2

version 1.1.1.1, 2000/01/10 15:35:27 version 1.1.1.2, 2000/09/09 14:12:59
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 /* mpz_tdiv_q -- divide two integers and produce a quotient.  /* mpz_tdiv_q -- divide two integers and produce a quotient.
   
 Copyright (C) 1991, 1993, 1994, 1996 Free Software Foundation, Inc.  Copyright (C) 1991, 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 33  mpz_tdiv_q (quot, num, den)
Line 33  mpz_tdiv_q (quot, num, den)
      mpz_srcptr den;       mpz_srcptr den;
 #endif  #endif
 {  {
   mp_srcptr np, dp;    mp_size_t ql;
   mp_ptr qp, rp;    mp_size_t ns, ds, nl, dl;
   mp_size_t nsize = num->_mp_size;    mp_ptr np, dp, qp, rp;
   mp_size_t dsize = den->_mp_size;  
   mp_size_t qsize, rsize;  
   mp_size_t sign_quotient = nsize ^ dsize;  
   unsigned normalization_steps;  
   mp_limb_t q_limb;  
   TMP_DECL (marker);    TMP_DECL (marker);
   
   nsize = ABS (nsize);    ns = SIZ (num);
   dsize = ABS (dsize);    ds = SIZ (den);
     nl = ABS (ns);
     dl = ABS (ds);
     ql = nl - dl + 1;
   
   /* Ensure space is enough for quotient. */    if (dl == 0)
       DIVIDE_BY_ZERO;
   
   qsize = nsize - dsize + 1;    /* qsize cannot be bigger than this.  */    if (ql <= 0)
   if (qsize <= 0)  
     {      {
       quot->_mp_size = 0;        SIZ (quot) = 0;
       return;        return;
     }      }
   
   if (quot->_mp_alloc < qsize)    MPZ_REALLOC (quot, ql);
     _mpz_realloc (quot, qsize);  
   
   qp = quot->_mp_d;  
   np = num->_mp_d;  
   dp = den->_mp_d;  
   
   /* Optimize division by a single-limb divisor.  */  
   if (dsize == 1)  
     {  
       mpn_divmod_1 (qp, np, nsize, dp[0]);  
       qsize -= qp[qsize - 1] == 0;  
       quot->_mp_size = sign_quotient >= 0 ? qsize : -qsize;  
       return;  
     }  
   
   TMP_MARK (marker);    TMP_MARK (marker);
     qp = PTR (quot);
     rp = (mp_ptr) TMP_ALLOC (dl * BYTES_PER_MP_LIMB);
     np = PTR (num);
     dp = PTR (den);
   
   rp = (mp_ptr) TMP_ALLOC ((nsize + 1) * BYTES_PER_MP_LIMB);    /* FIXME: We should think about how to handle the temporary allocation.
        Perhaps mpn_tdiv_qr should handle it, since it anyway often needs to
        allocate temp space.  */
   
   count_leading_zeros (normalization_steps, dp[dsize - 1]);    /* Copy denominator to temporary space if it overlaps with the quotient.  */
     if (dp == qp)
   /* Normalize the denominator, i.e. make its most significant bit set by  
      shifting it NORMALIZATION_STEPS bits to the left.  Also shift the  
      numerator the same number of steps (to keep the quotient the same!).  */  
   if (normalization_steps != 0)  
     {      {
       mp_ptr tp;        mp_ptr tp;
       mp_limb_t nlimb;        tp = (mp_ptr) TMP_ALLOC (dl * BYTES_PER_MP_LIMB);
         MPN_COPY (tp, dp, dl);
       /* Shift up the denominator setting the most significant bit of  
          the most significant word.  Use temporary storage not to clobber  
          the original contents of the denominator.  */  
       tp = (mp_ptr) TMP_ALLOC (dsize * BYTES_PER_MP_LIMB);  
       mpn_lshift (tp, dp, dsize, normalization_steps);  
       dp = tp;        dp = tp;
   
       /* Shift up the numerator, possibly introducing a new most  
          significant word.  Move the shifted numerator in the remainder  
          meanwhile.  */  
       nlimb = mpn_lshift (rp, np, nsize, normalization_steps);  
       if (nlimb != 0)  
         {  
           rp[nsize] = nlimb;  
           rsize = nsize + 1;  
         }  
       else  
         rsize = nsize;  
     }      }
   else    /* Copy numerator to temporary space if it overlaps with the quotient.  */
     if (np == qp)
     {      {
       /* The denominator is already normalized, as required.  Copy it to        mp_ptr tp;
          temporary space if it overlaps with the quotient.  */        tp = (mp_ptr) TMP_ALLOC (nl * BYTES_PER_MP_LIMB);
       if (dp == qp)        MPN_COPY (tp, np, nl);
         {        np = tp;
           dp = (mp_ptr) TMP_ALLOC (dsize * BYTES_PER_MP_LIMB);  
           MPN_COPY ((mp_ptr) dp, qp, dsize);  
         }  
   
       /* Move the numerator to the remainder.  */  
       MPN_COPY (rp, np, nsize);  
       rsize = nsize;  
     }      }
   
   q_limb = mpn_divmod (qp, rp, rsize, dp, dsize);    mpn_tdiv_qr (qp, rp, 0L, np, nl, dp, dl);
   
   qsize = rsize - dsize;    ql -=  qp[ql - 1] == 0;
   if (q_limb)  
     {  
       qp[qsize] = q_limb;  
       qsize += 1;  
     }  
   
   quot->_mp_size = sign_quotient >= 0 ? qsize : -qsize;    SIZ (quot) = (ns ^ ds) >= 0 ? ql : -ql;
   TMP_FREE (marker);    TMP_FREE (marker);
 }  }
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