| /* mpz_cdiv_r_ui -- Division rounding the quotient towards +infinity. The |
| remainder gets the opposite sign as the denominator. In order to make it |
| always fit into the return type, the negative of the true remainder is |
| returned. |
| |
| Copyright 1994, 1995, 1996, 2001, 2002, 2004, 2005 Free Software Foundation, |
| Inc. |
| |
| This file is part of the GNU MP Library. |
| |
| The GNU MP Library is free software; you can redistribute it and/or modify |
| it under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 3 of the License, or (at your |
| option) any later version. |
| |
| 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 |
| or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
| License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */ |
| |
| #include "gmp.h" |
| #include "gmp-impl.h" |
| |
| unsigned long int |
| mpz_cdiv_r_ui (mpz_ptr rem, mpz_srcptr dividend, unsigned long int divisor) |
| { |
| mp_size_t ns, nn; |
| mp_ptr np; |
| mp_limb_t rl; |
| |
| if (divisor == 0) |
| DIVIDE_BY_ZERO; |
| |
| ns = SIZ(dividend); |
| if (ns == 0) |
| { |
| SIZ(rem) = 0; |
| return 0; |
| } |
| |
| nn = ABS(ns); |
| np = PTR(dividend); |
| #if BITS_PER_ULONG > GMP_NUMB_BITS /* avoid warnings about shift amount */ |
| if (divisor > GMP_NUMB_MAX) |
| { |
| mp_limb_t dp[2]; |
| mp_ptr rp, qp; |
| mp_size_t rn; |
| TMP_DECL; |
| |
| MPZ_REALLOC (rem, 2); |
| rp = PTR(rem); |
| |
| if (nn == 1) /* tdiv_qr requirements; tested above for 0 */ |
| { |
| rl = np[0]; |
| rp[0] = rl; |
| } |
| else |
| { |
| TMP_MARK; |
| dp[0] = divisor & GMP_NUMB_MASK; |
| dp[1] = divisor >> GMP_NUMB_BITS; |
| qp = TMP_ALLOC_LIMBS (nn - 2 + 1); |
| mpn_tdiv_qr (qp, rp, (mp_size_t) 0, np, nn, dp, (mp_size_t) 2); |
| TMP_FREE; |
| rl = rp[0] + (rp[1] << GMP_NUMB_BITS); |
| } |
| |
| if (rl != 0 && ns >= 0) |
| { |
| rl = divisor - rl; |
| rp[0] = rl & GMP_NUMB_MASK; |
| rp[1] = rl >> GMP_NUMB_BITS; |
| } |
| |
| rn = 1 + (rl > GMP_NUMB_MAX); rn -= (rp[rn - 1] == 0); |
| SIZ(rem) = -rn; |
| } |
| else |
| #endif |
| { |
| rl = mpn_mod_1 (np, nn, (mp_limb_t) divisor); |
| if (rl == 0) |
| SIZ(rem) = 0; |
| else |
| { |
| if (ns >= 0) |
| rl = divisor - rl; |
| |
| PTR(rem)[0] = rl; |
| SIZ(rem) = -1; |
| } |
| } |
| |
| return rl; |
| } |