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-rw-r--r--Build/source/libs/gmp/gmp-6.0.0/mpz/combit.c103
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diff --git a/Build/source/libs/gmp/gmp-6.0.0/mpz/combit.c b/Build/source/libs/gmp/gmp-6.0.0/mpz/combit.c
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+++ b/Build/source/libs/gmp/gmp-6.0.0/mpz/combit.c
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+/* mpz_combit -- complement a specified bit.
+
+Copyright 2002, 2003, 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.h"
+#include "gmp-impl.h"
+
+void
+mpz_combit (mpz_ptr d, mp_bitcnt_t bit_index)
+{
+ mp_size_t dsize = SIZ(d);
+ mp_ptr dp = PTR(d);
+
+ mp_size_t limb_index = bit_index / GMP_NUMB_BITS;
+ mp_limb_t bit = (CNST_LIMB (1) << (bit_index % GMP_NUMB_BITS));
+
+ /* Check for the most common case: Positive input, no realloc or
+ normalization needed. */
+ if (limb_index + 1 < dsize)
+ dp[limb_index] ^= bit;
+
+ /* Check for the hairy case. d < 0, and we have all zero bits to the
+ right of the bit to toggle. */
+ else if (limb_index < -dsize && mpn_zero_p (dp, limb_index)
+ && (dp[limb_index] & (bit - 1)) == 0)
+ {
+ ASSERT (dsize < 0);
+ dsize = -dsize;
+
+ if (dp[limb_index] & bit)
+ {
+ /* We toggle the least significant one bit. Corresponds to
+ an add, with potential carry propagation, on the absolute
+ value. */
+ dp = MPZ_REALLOC (d, 1 + dsize);
+ dp[dsize] = 0;
+ MPN_INCR_U (dp + limb_index, 1 + dsize - limb_index, bit);
+ SIZ(d) = - dsize - dp[dsize];
+ }
+ else
+ {
+ /* We toggle a zero bit, subtract from the absolute value. */
+ MPN_DECR_U (dp + limb_index, dsize - limb_index, bit);
+ /* The absolute value shrinked by at most one bit. */
+ dsize -= dp[dsize - 1] == 0;
+ ASSERT (dsize > 0 && dp[dsize - 1] != 0);
+ SIZ (d) = -dsize;
+ }
+ }
+ else
+ {
+ /* Simple case: Toggle the bit in the absolute value. */
+ dsize = ABS(dsize);
+ if (limb_index < dsize)
+ {
+ mp_limb_t dlimb;
+ dlimb = dp[limb_index] ^ bit;
+ dp[limb_index] = dlimb;
+
+ /* Can happen only when limb_index = dsize - 1. Avoid SIZ(d)
+ bookkeeping in the common case. */
+ if (UNLIKELY ((dlimb == 0) + limb_index == dsize)) /* dsize == limb_index + 1 */
+ {
+ /* high limb became zero, must normalize */
+ MPN_NORMALIZE (dp, limb_index);
+ SIZ (d) = SIZ (d) >= 0 ? limb_index : -limb_index;
+ }
+ }
+ else
+ {
+ dp = MPZ_REALLOC (d, limb_index + 1);
+ MPN_ZERO(dp + dsize, limb_index - dsize);
+ dp[limb_index++] = bit;
+ SIZ(d) = SIZ(d) >= 0 ? limb_index : -limb_index;
+ }
+ }
+}