diff options
Diffstat (limited to 'vendor/gmp-6.3.0/mpz/cdiv_r_ui.c')
-rw-r--r-- | vendor/gmp-6.3.0/mpz/cdiv_r_ui.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/vendor/gmp-6.3.0/mpz/cdiv_r_ui.c b/vendor/gmp-6.3.0/mpz/cdiv_r_ui.c new file mode 100644 index 0000000..84d51db --- /dev/null +++ b/vendor/gmp-6.3.0/mpz/cdiv_r_ui.c @@ -0,0 +1,109 @@ +/* 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 1994-1996, 2001, 2002, 2004, 2005, 2012, 2015 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_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 (UNLIKELY (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; + + rp = MPZ_REALLOC (rem, 2); + + 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; + + MPZ_NEWALLOC (rem, 1)[0] = rl; + SIZ(rem) = -1; + } + } + + return rl; +} |