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Diff for /OpenXM_contrib/gmp/mpq/Attic/get_d.c between version 1.1.1.1 and 1.1.1.3

version 1.1.1.1, 2000/01/10 15:35:26 version 1.1.1.3, 2003/08/25 16:06:34
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 /* double mpq_get_d (mpq_t src) -- Return the double approximation to SRC.  /* double mpq_get_d (mpq_t src) -- Return the double approximation to SRC.
   
 Copyright (C) 1995, 1996 Free Software Foundation, Inc.  Copyright 1995, 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 49  MA 02111-1307, USA. */
Line 49  MA 02111-1307, USA. */
 */  */
   
 double  double
 #if __STDC__  
 mpq_get_d (const MP_RAT *src)  mpq_get_d (const MP_RAT *src)
 #else  
 mpq_get_d (src)  
      const MP_RAT *src;  
 #endif  
 {  {
   mp_ptr np, dp;    mp_ptr np, dp;
   mp_ptr rp;    mp_ptr rp;
Line 62  mpq_get_d (src)
Line 57  mpq_get_d (src)
   mp_size_t dsize = src->_mp_den._mp_size;    mp_size_t dsize = src->_mp_den._mp_size;
   mp_size_t qsize, rsize;    mp_size_t qsize, rsize;
   mp_size_t sign_quotient = nsize ^ dsize;    mp_size_t sign_quotient = nsize ^ dsize;
   unsigned normalization_steps;  
   mp_limb_t qlimb;    mp_limb_t qlimb;
 #define N_QLIMBS (1 + (sizeof (double) + BYTES_PER_MP_LIMB-1) / BYTES_PER_MP_LIMB)  #define N_QLIMBS (1 + (sizeof (double) + BYTES_PER_MP_LIMB-1) / BYTES_PER_MP_LIMB)
   mp_limb_t qp[N_QLIMBS + 1];    mp_limb_t qarr[N_QLIMBS + 1];
     mp_ptr qp = qarr;
   TMP_DECL (marker);    TMP_DECL (marker);
   
   if (nsize == 0)    if (nsize == 0)
Line 80  mpq_get_d (src)
Line 75  mpq_get_d (src)
   rsize = dsize + N_QLIMBS;    rsize = dsize + N_QLIMBS;
   rp = (mp_ptr) TMP_ALLOC ((rsize + 1) * BYTES_PER_MP_LIMB);    rp = (mp_ptr) TMP_ALLOC ((rsize + 1) * BYTES_PER_MP_LIMB);
   
   count_leading_zeros (normalization_steps, dp[dsize - 1]);  
   
   /* Normalize the denominator, i.e. make its most significant bit set by    /* Normalize the denominator, i.e. make its most significant bit set by
      shifting it NORMALIZATION_STEPS bits to the left.  Also shift the       shifting it NORMALIZATION_STEPS bits to the left.  Also shift the
      numerator the same number of steps (to keep the quotient the same!).  */       numerator the same number of steps (to keep the quotient the same!).  */
   if (normalization_steps != 0)    if ((dp[dsize - 1] & GMP_NUMB_HIGHBIT) == 0)
     {      {
       mp_ptr tp;        mp_ptr tp;
       mp_limb_t nlimb;        mp_limb_t nlimb;
         unsigned normalization_steps;
   
         count_leading_zeros (normalization_steps, dp[dsize - 1]);
         normalization_steps -= GMP_NAIL_BITS;
   
       /* Shift up the denominator setting the most significant bit of        /* Shift up the denominator setting the most significant bit of
          the most significant limb.  Use temporary storage not to clobber           the most significant limb.  Use temporary storage not to clobber
          the original contents of the denominator.  */           the original contents of the denominator.  */
Line 138  mpq_get_d (src)
Line 135  mpq_get_d (src)
   {    {
     double res;      double res;
     mp_size_t i;      mp_size_t i;
       mp_size_t scale = nsize - dsize - N_QLIMBS;
   
   #if defined (__vax__)
       /* Ignore excess quotient limbs.  This is necessary on a vax
          with its small double exponent, since we'd otherwise get
          exponent overflow while forming RES.  */
       if (qsize > N_QLIMBS)
         {
           qp += qsize - N_QLIMBS;
           scale += qsize - N_QLIMBS;
           qsize = N_QLIMBS;
         }
   #endif
   
     res = qp[qsize - 1];      res = qp[qsize - 1];
     for (i = qsize - 2; i >= 0; i--)      for (i = qsize - 2; i >= 0; i--)
       res = res * MP_BASE_AS_DOUBLE + qp[i];        res = res * MP_BASE_AS_DOUBLE + qp[i];
   
     res = __gmp_scale2 (res, BITS_PER_MP_LIMB * (nsize - dsize - N_QLIMBS));      res = __gmp_scale2 (res, GMP_NUMB_BITS * scale);
   
     TMP_FREE (marker);      TMP_FREE (marker);
     return sign_quotient >= 0 ? res : -res;      return sign_quotient >= 0 ? res : -res;
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  Added in v.1.1.1.3
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