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-rw-r--r--Build/source/libs/gmp/gmp-6.0.0/mpz/lucnum2_ui.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/Build/source/libs/gmp/gmp-6.0.0/mpz/lucnum2_ui.c b/Build/source/libs/gmp/gmp-6.0.0/mpz/lucnum2_ui.c
new file mode 100644
index 00000000000..f8e4fb356f0
--- /dev/null
+++ b/Build/source/libs/gmp/gmp-6.0.0/mpz/lucnum2_ui.c
@@ -0,0 +1,90 @@
+/* mpz_lucnum2_ui -- calculate Lucas numbers.
+
+Copyright 2001, 2003, 2005, 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 <stdio.h>
+#include "gmp.h"
+#include "gmp-impl.h"
+
+
+void
+mpz_lucnum2_ui (mpz_ptr ln, mpz_ptr lnsub1, unsigned long n)
+{
+ mp_ptr lp, l1p, f1p;
+ mp_size_t size;
+ mp_limb_t c;
+ TMP_DECL;
+
+ ASSERT (ln != lnsub1);
+
+ /* handle small n quickly, and hide the special case for L[-1]=-1 */
+ if (n <= FIB_TABLE_LUCNUM_LIMIT)
+ {
+ mp_limb_t f = FIB_TABLE (n);
+ mp_limb_t f1 = FIB_TABLE ((int) n - 1);
+
+ /* L[n] = F[n] + 2F[n-1] */
+ PTR(ln)[0] = f + 2*f1;
+ SIZ(ln) = 1;
+
+ /* L[n-1] = 2F[n] - F[n-1], but allow for L[-1]=-1 */
+ PTR(lnsub1)[0] = (n == 0 ? 1 : 2*f - f1);
+ SIZ(lnsub1) = (n == 0 ? -1 : 1);
+
+ return;
+ }
+
+ TMP_MARK;
+ size = MPN_FIB2_SIZE (n);
+ f1p = TMP_ALLOC_LIMBS (size);
+
+ lp = MPZ_REALLOC (ln, size+1);
+ l1p = MPZ_REALLOC (lnsub1, size+1);
+
+ size = mpn_fib2_ui (l1p, f1p, n);
+
+ /* L[n] = F[n] + 2F[n-1] */
+#if HAVE_NATIVE_mpn_addlsh1_n
+ c = mpn_addlsh1_n (lp, l1p, f1p, size);
+#else
+ c = mpn_lshift (lp, f1p, size, 1);
+ c += mpn_add_n (lp, lp, l1p, size);
+#endif
+ lp[size] = c;
+ SIZ(ln) = size + (c != 0);
+
+ /* L[n-1] = 2F[n] - F[n-1] */
+ c = mpn_lshift (l1p, l1p, size, 1);
+ c -= mpn_sub_n (l1p, l1p, f1p, size);
+ ASSERT ((mp_limb_signed_t) c >= 0);
+ l1p[size] = c;
+ SIZ(lnsub1) = size + (c != 0);
+
+ TMP_FREE;
+}