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Diff for /OpenXM_contrib/gmp/mpz/Attic/pow_ui.c between version 1.1.1.1 and 1.1.1.3

version 1.1.1.1, 2000/01/10 15:35:27 version 1.1.1.3, 2003/08/25 16:06:33
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 /* mpz_pow_ui(res, base, exp) -- Set RES to BASE**EXP.  /* mpz_pow_ui -- mpz raised to ulong.
   
 Copyright (C) 1991, 1993, 1994, 1996 Free Software Foundation, Inc.  Copyright 2001 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. */
   
 #ifdef BERKELEY_MP  
 #include "mp.h"  
 #endif  
 #include "gmp.h"  #include "gmp.h"
 #include "gmp-impl.h"  #include "gmp-impl.h"
 #include "longlong.h"  
   
 #ifndef BERKELEY_MP  
 void  void
 #if __STDC__  
 mpz_pow_ui (mpz_ptr r, mpz_srcptr b, unsigned long int e)  mpz_pow_ui (mpz_ptr r, mpz_srcptr b, unsigned long int e)
 #else  
 mpz_pow_ui (r, b, e)  
      mpz_ptr r;  
      mpz_srcptr b;  
      unsigned long int e;  
 #endif  
 #else /* BERKELEY_MP */  
 void  
 #if __STDC__  
 rpow (const MINT *b, signed short int e, MINT *r)  
 #else  
 rpow (b, e, r)  
      const MINT *b;  
      signed short int e;  
      MINT *r;  
 #endif  
 #endif /* BERKELEY_MP */  
 {  {
   mp_ptr rp, bp, tp, xp;    mpz_n_pow_ui (r, PTR(b), (mp_size_t) SIZ(b), e);
   mp_size_t rsize, bsize;  
   int cnt, i;  
   mp_limb_t blimb;  
   TMP_DECL (marker);  
   
   bsize = ABS (b->_mp_size);  
   
   /* Single out cases that give result == 0 or 1.  These tests are here  
      to simplify the general code below, not to optimize.  */  
   if (e == 0)  
     {  
       r->_mp_d[0] = 1;  
       r->_mp_size = 1;  
       return;  
     }  
   if (bsize == 0  
 #ifdef BERKELEY_MP  
       || e < 0  
 #endif  
       )  
     {  
       r->_mp_size = 0;  
       return;  
     }  
   
   bp = b->_mp_d;  
   
   blimb = bp[bsize - 1];  
   if (bsize == 1 && blimb < 0x100)  
     {  
       /* Estimate space requirements accurately.  Using the code from the  
          `else' path would over-estimate space requirements wildly.   */  
       float lb = __mp_bases[blimb].chars_per_bit_exactly;  
       rsize = 2 + ((mp_size_t) (e / lb) / BITS_PER_MP_LIMB);  
     }  
   else  
     {  
       /* Over-estimate space requirements somewhat.  */  
       count_leading_zeros (cnt, blimb);  
       rsize = bsize * e - cnt * e / BITS_PER_MP_LIMB + 1;  
     }  
   
   TMP_MARK (marker);  
   
   /* The two areas are used to alternatingly hold the input and recieve the  
      product for mpn_mul.  (This scheme is used to fulfill the requirements  
      of mpn_mul; that the product space may not be the same as any of the  
      input operands.)  */  
   rp = (mp_ptr) TMP_ALLOC (rsize * BYTES_PER_MP_LIMB);  
   tp = (mp_ptr) TMP_ALLOC (rsize * BYTES_PER_MP_LIMB);  
   
   MPN_COPY (rp, bp, bsize);  
   rsize = bsize;  
   count_leading_zeros (cnt, e);  
   
   for (i = BITS_PER_MP_LIMB - cnt - 2; i >= 0; i--)  
     {  
       mpn_mul_n (tp, rp, rp, rsize);  
       rsize = 2 * rsize;  
       rsize -= tp[rsize - 1] == 0;  
       xp = tp; tp = rp; rp = xp;  
   
       if ((e & ((mp_limb_t) 1 << i)) != 0)  
         {  
           rsize = rsize + bsize - (mpn_mul (tp, rp, rsize, bp, bsize) == 0);  
           xp = tp; tp = rp; rp = xp;  
         }  
     }  
   
   /* Now then we know the exact space requirements, reallocate if  
      necessary.  */  
   if (r->_mp_alloc < rsize)  
     _mpz_realloc (r, rsize);  
   
   MPN_COPY (r->_mp_d, rp, rsize);  
   r->_mp_size = (e & 1) == 0 || b->_mp_size >= 0 ? rsize : -rsize;  
   TMP_FREE (marker);  
 }  }
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