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-rw-r--r--vendor/gmp-6.3.0/mpz/xor.c146
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diff --git a/vendor/gmp-6.3.0/mpz/xor.c b/vendor/gmp-6.3.0/mpz/xor.c
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+/* mpz_xor -- Logical xor.
+
+Copyright 1991, 1993, 1994, 1996, 1997, 2000, 2001, 2005, 2012,
+2015-2018 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_xor (mpz_ptr res, mpz_srcptr op1, mpz_srcptr op2)
+{
+ mp_srcptr op1_ptr, op2_ptr;
+ mp_size_t op1_size, op2_size;
+ mp_ptr res_ptr;
+ mp_size_t res_size;
+
+ op1_size = SIZ(op1);
+ op2_size = SIZ(op2);
+
+ if (op1_size < op2_size)
+ {
+ MPZ_SRCPTR_SWAP (op1, op2);
+ MP_SIZE_T_SWAP (op1_size, op2_size);
+ }
+
+ op1_ptr = PTR(op1);
+ res_ptr = PTR(res);
+
+ if (op2_size >= 0)
+ {
+ if (res_ptr != op1_ptr)
+ {
+ res_ptr = MPZ_REALLOC (res, op1_size);
+ MPN_COPY (res_ptr + op2_size, op1_ptr + op2_size,
+ op1_size - op2_size);
+ }
+ if (LIKELY (op2_size != 0))
+ mpn_xor_n (res_ptr, op1_ptr, PTR(op2), op2_size);
+ res_size = op1_size;
+
+ MPN_NORMALIZE (res_ptr, res_size);
+ SIZ(res) = res_size;
+ }
+ else
+ {
+ mp_ptr opx;
+ TMP_DECL;
+
+ op2_size = -op2_size;
+ TMP_MARK;
+ if (op1_size < 0)
+ {
+ mp_ptr opy;
+
+ /* Both operands are negative, the result will be positive.
+ (-OP1) ^ (-OP2) =
+ = ~(OP1 - 1) ^ ~(OP2 - 1) =
+ = (OP1 - 1) ^ (OP2 - 1) */
+
+ op1_size = -op1_size;
+
+ /* Possible optimization: Decrease mpn_sub precision,
+ as we won't use the entire res of both. */
+ TMP_ALLOC_LIMBS_2 (opx, op1_size, opy, op2_size);
+ mpn_sub_1 (opx, op1_ptr, op1_size, (mp_limb_t) 1);
+ op1_ptr = opx;
+
+ mpn_sub_1 (opy, PTR(op2), op2_size, (mp_limb_t) 1);
+ op2_ptr = opy;
+
+ res_ptr = MPZ_NEWALLOC (res, op2_size);
+ /* Don't re-read OP1_PTR and OP2_PTR. They point to temporary
+ space--never to the space PTR(res) used to point to before
+ reallocation. */
+
+ MPN_COPY (res_ptr + op1_size, op2_ptr + op1_size,
+ op2_size - op1_size);
+ mpn_xor_n (res_ptr, op1_ptr, op2_ptr, op1_size);
+ TMP_FREE;
+ res_size = op2_size;
+
+ MPN_NORMALIZE (res_ptr, res_size);
+ SIZ(res) = res_size;
+ }
+ else
+ {
+ /* Operand 2 negative, so will be the result.
+ -(OP1 ^ (-OP2)) = -(OP1 ^ ~(OP2 - 1)) =
+ = ~(OP1 ^ ~(OP2 - 1)) + 1 =
+ = (OP1 ^ (OP2 - 1)) + 1 */
+
+ res_size = MAX (op1_size, op2_size);
+ res_ptr = MPZ_REALLOC (res, res_size + 1);
+ op1_ptr = PTR(op1);
+
+ opx = TMP_ALLOC_LIMBS (op2_size);
+ mpn_sub_1 (opx, PTR(op2), op2_size, (mp_limb_t) 1);
+ op2_ptr = opx;
+
+ if (res_size == op1_size)
+ {
+ MPN_COPY (res_ptr + op2_size, op1_ptr + op2_size, op1_size - op2_size);
+ mpn_xor_n (res_ptr, op1_ptr, op2_ptr, op2_size);
+ }
+ else
+ {
+ MPN_COPY (res_ptr + op1_size, op2_ptr + op1_size, op2_size - op1_size);
+ if (LIKELY (op1_size != 0))
+ mpn_xor_n (res_ptr, op1_ptr, op2_ptr, op1_size);
+ }
+ TMP_FREE;
+
+ res_ptr[res_size] = 0;
+ MPN_INCR_U (res_ptr, res_size + 1, (mp_limb_t) 1);
+ res_size += res_ptr[res_size];
+
+ MPN_NORMALIZE_NOT_ZERO (res_ptr, res_size);
+ SIZ(res) = -res_size;
+ }
+ }
+}