diff options
Diffstat (limited to 'vendor/gmp-6.3.0/mpz/cdiv_q_ui.c')
-rw-r--r-- | vendor/gmp-6.3.0/mpz/cdiv_q_ui.c | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/vendor/gmp-6.3.0/mpz/cdiv_q_ui.c b/vendor/gmp-6.3.0/mpz/cdiv_q_ui.c new file mode 100644 index 0000000..269d9a3 --- /dev/null +++ b/vendor/gmp-6.3.0/mpz/cdiv_q_ui.c @@ -0,0 +1,102 @@ +/* mpz_cdiv_q_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, 1996, 1999, 2001, 2002, 2004, 2012 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 either: + + * 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. + +or + + * the GNU General Public License as published by the Free Software + Foundation; either version 2 of the License, or (at your option) any + later version. + +or both in parallel, as here. + +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 General Public License +for more details. + +You should have received copies of the GNU General Public License and the +GNU Lesser General Public License along with the GNU MP Library. If not, +see https://www.gnu.org/licenses/. */ + +#include "gmp-impl.h" + +unsigned long int +mpz_cdiv_q_ui (mpz_ptr quot, mpz_srcptr dividend, unsigned long int divisor) +{ + mp_size_t ns, nn, qn; + mp_ptr np, qp; + mp_limb_t rl; + + if (UNLIKELY (divisor == 0)) + DIVIDE_BY_ZERO; + + ns = SIZ(dividend); + if (ns == 0) + { + SIZ(quot) = 0; + return 0; + } + + nn = ABS(ns); + qp = MPZ_REALLOC (quot, nn); + 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], rp[2]; + + if (nn == 1) /* tdiv_qr requirements; tested above for 0 */ + { + qp[0] = 0; + rl = np[0]; + qn = 1; /* a white lie, fixed below */ + } + else + { + 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; + } + + if (rl != 0 && ns >= 0) + { + mpn_incr_u (qp, (mp_limb_t) 1); + rl = divisor - rl; + } + + qn -= qp[qn - 1] == 0; qn -= qn != 0 && qp[qn - 1] == 0; + } + else +#endif + { + rl = mpn_divrem_1 (qp, (mp_size_t) 0, np, nn, (mp_limb_t) divisor); + + if (rl != 0 && ns >= 0) + { + mpn_incr_u (qp, (mp_limb_t) 1); + rl = divisor - rl; + } + + qn = nn - (qp[nn - 1] == 0); + } + + SIZ(quot) = ns >= 0 ? qn : -qn; + return rl; +} |