| /* mpz_tdiv_qr_ui(quot,rem,dividend,short_divisor) -- |
| Set QUOT to DIVIDEND / SHORT_DIVISOR |
| and REM to DIVIDEND mod SHORT_DIVISOR. |
| |
| Copyright 1991, 1993, 1994, 1996, 1998, 2001, 2002, 2004 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_tdiv_qr_ui (mpz_ptr quot, mpz_ptr rem, mpz_srcptr dividend, unsigned long int divisor) |
| { |
| mp_size_t ns, nn, qn; |
| mp_ptr np, qp; |
| mp_limb_t rl; |
| |
| if (divisor == 0) |
| DIVIDE_BY_ZERO; |
| |
| ns = SIZ(dividend); |
| if (ns == 0) |
| { |
| SIZ(quot) = 0; |
| SIZ(rem) = 0; |
| return 0; |
| } |
| |
| nn = ABS(ns); |
| MPZ_REALLOC (quot, nn); |
| qp = PTR(quot); |
| 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; |
| mp_size_t rn; |
| |
| if (nn == 1) /* tdiv_qr requirements; tested above for 0 */ |
| { |
| SIZ(quot) = 0; |
| rl = np[0]; |
| SIZ(rem) = ns >= 0 ? 1 : -1; |
| PTR(rem)[0] = rl; |
| return rl; |
| } |
| |
| MPZ_REALLOC (rem, 2); |
| rp = PTR(rem); |
| |
| dp[0] = divisor & GMP_NUMB_MASK; |
| dp[1] = divisor >> GMP_NUMB_BITS; |
| mpn_tdiv_qr (qp, rp, (mp_size_t) 0, np, nn, dp, (mp_size_t) 2); |
| rl = rp[0] + (rp[1] << GMP_NUMB_BITS); |
| qn = nn - 2 + 1; qn -= qp[qn - 1] == 0; qn -= qn != 0 && qp[qn - 1] == 0; |
| rn = 2 - (rp[1] == 0); rn -= (rp[rn - 1] == 0); |
| SIZ(rem) = ns >= 0 ? rn : -rn; |
| } |
| else |
| #endif |
| { |
| rl = mpn_divrem_1 (qp, (mp_size_t) 0, np, nn, (mp_limb_t) divisor); |
| if (rl == 0) |
| SIZ(rem) = 0; |
| else |
| { |
| /* Store the single-limb remainder. We don't check if there's space |
| for just one limb, since no function ever makes zero space. */ |
| SIZ(rem) = ns >= 0 ? 1 : -1; |
| PTR(rem)[0] = rl; |
| } |
| qn = nn - (qp[nn - 1] == 0); |
| } |
| |
| SIZ(quot) = ns >= 0 ? qn : -qn; |
| return rl; |
| } |