From 11da511c784eca003deb90c23570f0873954e0de Mon Sep 17 00:00:00 2001 From: Duncan Wilkie Date: Sat, 18 Nov 2023 06:11:09 -0600 Subject: Initial commit. --- gmp-6.3.0/mpz/mul_2exp.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) create mode 100644 gmp-6.3.0/mpz/mul_2exp.c (limited to 'gmp-6.3.0/mpz/mul_2exp.c') diff --git a/gmp-6.3.0/mpz/mul_2exp.c b/gmp-6.3.0/mpz/mul_2exp.c new file mode 100644 index 0000000..6144d0d --- /dev/null +++ b/gmp-6.3.0/mpz/mul_2exp.c @@ -0,0 +1,72 @@ +/* mpz_mul_2exp -- Multiply a bignum by 2**CNT + +Copyright 1991, 1993, 1994, 1996, 2001, 2002, 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" + +void +mpz_mul_2exp (mpz_ptr r, mpz_srcptr u, mp_bitcnt_t cnt) +{ + mp_size_t un, rn; + mp_size_t limb_cnt; + mp_ptr rp; + mp_srcptr up; + mp_limb_t rlimb; + + un = ABSIZ (u); + limb_cnt = cnt / GMP_NUMB_BITS; + rn = un + limb_cnt; + + if (un == 0) + rn = 0; + else + { + rp = MPZ_REALLOC (r, rn + 1); + up = PTR(u); + + cnt %= GMP_NUMB_BITS; + if (cnt != 0) + { + rlimb = mpn_lshift (rp + limb_cnt, up, un, cnt); + rp[rn] = rlimb; + rn += (rlimb != 0); + } + else + { + MPN_COPY_DECR (rp + limb_cnt, up, un); + } + + /* Zero all whole limbs at low end. Do it here and not before calling + mpn_lshift, not to lose for U == R. */ + MPN_ZERO (rp, limb_cnt); + } + + SIZ(r) = SIZ(u) >= 0 ? rn : -rn; +} -- cgit v1.2.3