version 1.1.1.1, 2000/01/10 15:35:27 |
version 1.1.1.2, 2000/09/09 14:12:56 |
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/* mpz_powm_ui(res,base,exp,mod) -- Set RES to (base**exp) mod MOD. |
/* mpz_powm_ui(res,base,exp,mod) -- Set RES to (base**exp) mod MOD. |
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Copyright (C) 1991, 1993, 1994, 1996 Free Software Foundation, Inc. |
Copyright (C) 1991, 1993, 1994, 1996, 1997, 2000 Free Software Foundation, |
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Inc. |
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This file is part of the GNU MP Library. |
This file is part of the GNU MP Library. |
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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. |
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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. |
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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. */ |
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#include <stdio.h> /* for NULL */ |
#include "gmp.h" |
#include "gmp.h" |
#include "gmp-impl.h" |
#include "gmp-impl.h" |
#include "longlong.h" |
#include "longlong.h" |
Line 49 mpz_powm_ui (res, base, exp, mod) |
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Line 51 mpz_powm_ui (res, base, exp, mod) |
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rp = res->_mp_d; |
rp = res->_mp_d; |
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if (msize == 0) |
if (msize == 0) |
msize = 1 / msize; /* provoke a signal */ |
DIVIDE_BY_ZERO; |
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if (exp == 0) |
if (exp == 0) |
{ |
{ |
rp[0] = 1; |
/* Exponent is zero, result is 1 mod MOD, i.e., 1 or 0 |
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depending on if MOD equals 1. */ |
res->_mp_size = (msize == 1 && (mod->_mp_d)[0] == 1) ? 0 : 1; |
res->_mp_size = (msize == 1 && (mod->_mp_d)[0] == 1) ? 0 : 1; |
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rp[0] = 1; |
return; |
return; |
} |
} |
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Line 166 mpz_powm_ui (res, base, exp, mod) |
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Line 170 mpz_powm_ui (res, base, exp, mod) |
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mpn_mul_n (xp, rp, rp, rsize); |
mpn_mul_n (xp, rp, rp, rsize); |
xsize = 2 * rsize; |
xsize = 2 * rsize; |
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xsize -= xp[xsize - 1] == 0; |
if (xsize > msize) |
if (xsize > msize) |
{ |
{ |
mpn_divmod (xp + msize, xp, xsize, mp, msize); |
mpn_divmod (xp + msize, xp, xsize, mp, msize); |
Line 179 mpz_powm_ui (res, base, exp, mod) |
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Line 184 mpz_powm_ui (res, base, exp, mod) |
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{ |
{ |
mpn_mul (xp, rp, rsize, bp, bsize); |
mpn_mul (xp, rp, rsize, bp, bsize); |
xsize = rsize + bsize; |
xsize = rsize + bsize; |
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xsize -= xp[xsize - 1] == 0; |
if (xsize > msize) |
if (xsize > msize) |
{ |
{ |
mpn_divmod (xp + msize, xp, xsize, mp, msize); |
mpn_divmod (xp + msize, xp, xsize, mp, msize); |
Line 226 mpz_powm_ui (res, base, exp, mod) |
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Line 232 mpz_powm_ui (res, base, exp, mod) |
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MPN_NORMALIZE (rp, rsize); |
MPN_NORMALIZE (rp, rsize); |
} |
} |
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res->_mp_size = negative_result == 0 ? rsize : -rsize; |
if (negative_result && rsize != 0) |
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{ |
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if (mod_shift_cnt != 0) |
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mpn_rshift (mp, mp, msize, mod_shift_cnt); |
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mpn_sub (rp, mp, msize, rp, rsize); |
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rsize = msize; |
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MPN_NORMALIZE (rp, rsize); |
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} |
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res->_mp_size = rsize; |
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if (free_me != NULL) |
if (free_me != NULL) |
(*_mp_free_func) (free_me, free_me_size * BYTES_PER_MP_LIMB); |
(*_mp_free_func) (free_me, free_me_size * BYTES_PER_MP_LIMB); |