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-rw-r--r--Build/source/libs/gmp/gmp-6.0.0/mpz/fac_ui.c108
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diff --git a/Build/source/libs/gmp/gmp-6.0.0/mpz/fac_ui.c b/Build/source/libs/gmp/gmp-6.0.0/mpz/fac_ui.c
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+/* mpz_fac_ui(RESULT, N) -- Set RESULT to N!.
+
+Contributed to the GNU project by Marco Bodrato.
+
+Copyright 1991, 1993-1995, 2000-2003, 2011, 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"
+
+#define FACTOR_LIST_STORE(P, PR, MAX_PR, VEC, I) \
+ do { \
+ if ((PR) > (MAX_PR)) { \
+ (VEC)[(I)++] = (PR); \
+ (PR) = (P); \
+ } else \
+ (PR) *= (P); \
+ } while (0)
+
+#if TUNE_PROGRAM_BUILD
+#define FACTORS_PER_LIMB (GMP_NUMB_BITS / (LOG2C(FAC_DSC_THRESHOLD_LIMIT-1)+1))
+#else
+#define FACTORS_PER_LIMB (GMP_NUMB_BITS / (LOG2C(FAC_ODD_THRESHOLD)+1))
+#endif
+
+/* Computes n!, the factorial of n.
+ WARNING: it assumes that n fits in a limb!
+ */
+void
+mpz_fac_ui (mpz_ptr x, unsigned long n)
+{
+ static const mp_limb_t table[] = { ONE_LIMB_FACTORIAL_TABLE };
+
+ ASSERT (n <= GMP_NUMB_MAX);
+
+ if (n < numberof (table))
+ {
+ PTR (x)[0] = table[n];
+ SIZ (x) = 1;
+ }
+ else if (BELOW_THRESHOLD (n, FAC_ODD_THRESHOLD))
+ {
+ mp_limb_t prod, max_prod;
+ mp_size_t j;
+ mp_ptr factors;
+ TMP_SDECL;
+
+ TMP_SMARK;
+ factors = TMP_SALLOC_LIMBS (2 + (n - numberof (table)) / FACTORS_PER_LIMB);
+
+ factors[0] = table[numberof (table)-1];
+ j = 1;
+ prod = n;
+#if TUNE_PROGRAM_BUILD
+ max_prod = GMP_NUMB_MAX / FAC_DSC_THRESHOLD_LIMIT;
+#else
+ max_prod = GMP_NUMB_MAX / (FAC_ODD_THRESHOLD | 1);
+#endif
+ while (--n >= numberof (table))
+ FACTOR_LIST_STORE (n, prod, max_prod, factors, j);
+
+ factors[j++] = prod;
+ mpz_prodlimbs (x, factors, j);
+
+ TMP_SFREE;
+ }
+ else
+ {
+ mp_limb_t count;
+ mpz_oddfac_1 (x, n, 0);
+ if (n <= TABLE_LIMIT_2N_MINUS_POPC_2N)
+ count = __gmp_fac2cnt_table[n / 2 - 1];
+ else
+ {
+ popc_limb (count, n);
+ count = n - count;
+ }
+ mpz_mul_2exp (x, x, count);
+ }
+}
+
+#undef FACTORS_PER_LIMB
+#undef FACTOR_LIST_STORE