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Diffstat (limited to 'vendor/gmp-6.3.0/mpz/tdiv_r_2exp.c')
-rw-r--r--vendor/gmp-6.3.0/mpz/tdiv_r_2exp.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/vendor/gmp-6.3.0/mpz/tdiv_r_2exp.c b/vendor/gmp-6.3.0/mpz/tdiv_r_2exp.c
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+/* mpz_tdiv_r_2exp -- Divide an integer by 2**CNT and produce a remainder.
+
+Copyright 1991, 1993-1995, 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_tdiv_r_2exp (mpz_ptr res, mpz_srcptr in, mp_bitcnt_t cnt)
+{
+ mp_size_t in_size = ABSIZ (in);
+ mp_size_t res_size;
+ mp_size_t limb_cnt = cnt / GMP_NUMB_BITS;
+ mp_srcptr in_ptr = PTR (in);
+
+ if (in_size > limb_cnt)
+ {
+ /* The input operand is (probably) greater than 2**CNT. */
+ mp_limb_t x;
+
+ x = in_ptr[limb_cnt] & (((mp_limb_t) 1 << cnt % GMP_NUMB_BITS) - 1);
+ if (x != 0)
+ {
+ res_size = limb_cnt + 1;
+ MPZ_REALLOC (res, res_size);
+
+ PTR (res)[limb_cnt] = x;
+ }
+ else
+ {
+ MPN_NORMALIZE (in_ptr, limb_cnt);
+
+ MPZ_REALLOC (res, limb_cnt);
+
+ res_size = limb_cnt;
+ }
+ }
+ else
+ {
+ /* The input operand is smaller than 2**CNT. We perform a no-op,
+ apart from that we might need to copy IN to RES. */
+ limb_cnt = in_size;
+ MPZ_REALLOC (res, limb_cnt);
+
+ res_size = limb_cnt;
+ }
+
+ if (res != in)
+ MPN_COPY (PTR (res), PTR (in), limb_cnt);
+ SIZ (res) = SIZ (in) >= 0 ? res_size : -res_size;
+}