version 1.1, 2000/01/10 15:35:27 |
version 1.1.1.3, 2003/08/25 16:06:33 |
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/* mpz_fdiv_qr_ui -- Division rounding the quotient towards -infinity. |
/* mpz_fdiv_qr_ui -- Division rounding the quotient towards -infinity. |
The remainder gets the same sign as the denominator. |
The remainder gets the same sign as the denominator. |
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Copyright (C) 1994, 1995, 1996 Free Software Foundation, Inc. |
Copyright 1994, 1995, 1996, 1999, 2001, 2002 Free Software Foundation, 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. */ |
Line 24 MA 02111-1307, USA. */ |
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Line 24 MA 02111-1307, USA. */ |
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#include "gmp-impl.h" |
#include "gmp-impl.h" |
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unsigned long int |
unsigned long int |
#if __STDC__ |
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mpz_fdiv_qr_ui (mpz_ptr quot, mpz_ptr rem, mpz_srcptr dividend, unsigned long int divisor) |
mpz_fdiv_qr_ui (mpz_ptr quot, mpz_ptr rem, mpz_srcptr dividend, unsigned long int divisor) |
#else |
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mpz_fdiv_qr_ui (quot, rem, dividend, divisor) |
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mpz_ptr quot; |
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mpz_ptr rem; |
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mpz_srcptr dividend; |
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unsigned long int divisor; |
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#endif |
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{ |
{ |
mp_size_t dividend_size; |
mp_size_t ns, nn, qn; |
mp_size_t size; |
mp_ptr np, qp; |
mp_ptr quot_ptr; |
mp_limb_t rl; |
mp_limb_t remainder_limb; |
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dividend_size = dividend->_mp_size; |
if (divisor == 0) |
size = ABS (dividend_size); |
DIVIDE_BY_ZERO; |
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if (quot->_mp_alloc < size) |
ns = SIZ(dividend); |
_mpz_realloc (quot, size); |
if (ns == 0) |
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{ |
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SIZ(quot) = 0; |
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SIZ(rem) = 0; |
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return 0; |
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} |
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quot_ptr = quot->_mp_d; |
nn = ABS(ns); |
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MPZ_REALLOC (quot, nn); |
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qp = PTR(quot); |
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np = PTR(dividend); |
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remainder_limb = mpn_divmod_1 (quot_ptr, dividend->_mp_d, size, |
#if GMP_NAIL_BITS != 0 |
(mp_limb_t) divisor); |
if (divisor > GMP_NUMB_MAX) |
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if (remainder_limb != 0 && dividend_size < 0) |
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{ |
{ |
mpn_add_1 (quot_ptr, quot_ptr, size, (mp_limb_t) 1); |
mp_limb_t dp[2]; |
remainder_limb = divisor - remainder_limb; |
mp_ptr rp; |
} |
mp_size_t rn; |
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size -= size != 0 && quot_ptr[size - 1] == 0; |
MPZ_REALLOC (rem, 2); |
quot->_mp_size = dividend_size >= 0 ? size : -size; |
rp = PTR(rem); |
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rem->_mp_d[0] = remainder_limb; |
if (nn == 1) /* tdiv_qr requirements; tested above for 0 */ |
rem->_mp_size = remainder_limb != 0; |
{ |
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qp[0] = 0; |
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qn = 1; /* a white lie, fixed below */ |
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rl = np[0]; |
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rp[0] = rl; |
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} |
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else |
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{ |
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dp[0] = divisor & GMP_NUMB_MASK; |
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dp[1] = divisor >> GMP_NUMB_BITS; |
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mpn_tdiv_qr (qp, rp, (mp_size_t) 0, np, nn, dp, (mp_size_t) 2); |
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rl = rp[0] + (rp[1] << GMP_NUMB_BITS); |
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qn = nn - 2 + 1; |
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} |
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return remainder_limb; |
if (rl != 0 && ns < 0) |
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{ |
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mpn_incr_u (qp, (mp_limb_t) 1); |
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rl = divisor - rl; |
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rp[0] = rl & GMP_NUMB_MASK; |
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rp[1] = rl >> GMP_NUMB_BITS; |
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} |
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qn -= qp[qn - 1] == 0; qn -= qn != 0 && qp[qn - 1] == 0; |
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rn = 1 + (rl > GMP_NUMB_MAX); rn -= (rp[rn - 1] == 0); |
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SIZ(rem) = rn; |
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} |
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else |
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#endif |
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{ |
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rl = mpn_divrem_1 (qp, (mp_size_t) 0, np, nn, (mp_limb_t) divisor); |
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if (rl == 0) |
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SIZ(rem) = 0; |
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else |
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{ |
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if (ns < 0) |
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{ |
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mpn_incr_u (qp, (mp_limb_t) 1); |
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rl = divisor - rl; |
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} |
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PTR(rem)[0] = rl; |
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SIZ(rem) = rl != 0; |
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} |
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qn = nn - (qp[nn - 1] == 0); |
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} |
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SIZ(quot) = ns >= 0 ? qn : -qn; |
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return rl; |
} |
} |