diff options
Diffstat (limited to 'vendor/gmp-6.3.0/mpz/gcd_ui.c')
-rw-r--r-- | vendor/gmp-6.3.0/mpz/gcd_ui.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/vendor/gmp-6.3.0/mpz/gcd_ui.c b/vendor/gmp-6.3.0/mpz/gcd_ui.c new file mode 100644 index 0000000..64aa46d --- /dev/null +++ b/vendor/gmp-6.3.0/mpz/gcd_ui.c @@ -0,0 +1,92 @@ +/* mpz_gcd_ui -- Calculate the greatest common divisor of two integers. + +Copyright 1994, 1996, 1999-2004, 2015, 2022 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 <stdio.h> /* for NULL */ +#include "gmp-impl.h" + +unsigned long int +mpz_gcd_ui (mpz_ptr w, mpz_srcptr u, unsigned long int v) +{ + mp_size_t un; + mp_limb_t res; + +#if BITS_PER_ULONG > GMP_NUMB_BITS /* avoid warnings about shift amount */ + if (v > GMP_NUMB_MAX) + { + mpz_t vz, lw; + mp_limb_t vlimbs[2], wlimbs[2]; + + if (w == NULL) + { + PTR(lw) = wlimbs; + ALLOC(lw) = 2; + SIZ(lw) = 0; + w = lw; + } + vlimbs[0] = v & GMP_NUMB_MASK; + vlimbs[1] = v >> GMP_NUMB_BITS; + PTR(vz) = vlimbs; + SIZ(vz) = 2; + mpz_gcd (w, u, vz); + /* because v!=0 we will have w<=v hence fitting a ulong */ + ASSERT (mpz_fits_ulong_p (w)); + return mpz_get_ui (w); + } +#endif + + un = ABSIZ(u); + + if (un == 0) + res = v; + else if (v == 0) + { + if (w != NULL) + { + if (u != w) + { + MPZ_NEWALLOC (w, un); + MPN_COPY (PTR(w), PTR(u), un); + } + SIZ(w) = un; + } + /* Return u if it fits a ulong, otherwise 0. */ + res = PTR(u)[0]; + return (un == 1 && res <= ULONG_MAX ? res : 0); + } + else + res = mpn_gcd_1 (PTR(u), un, (mp_limb_t) v); + + if (w != NULL) + { + MPZ_NEWALLOC (w, 1)[0] = res; + SIZ(w) = res != 0; + } + return res; +} |