1 files changed, 83 insertions, 0 deletions
diff --git a/Build/source/libs/mpfr/mpfr-src/src/nbits_ulong.c b/Build/source/libs/mpfr/mpfr-src/src/nbits_ulong.c
new file mode 100644
index 00000000000..88d978c8c6e
--- /dev/null
+++ b/Build/source/libs/mpfr/mpfr-src/src/nbits_ulong.c
@@ -0,0 +1,83 @@
+/* mpfr_nbits_ulong -- number of significant bits in an unsigned long
+
+Copyright 2018-2020 Free Software Foundation, Inc.
+Contributed by the AriC and Caramba projects, INRIA.
+
+This file is part of the GNU MPFR Library.
+
+The GNU MPFR Library is free software; you can redistribute it and/or modify
+it under the terms of 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.
+
+The GNU MPFR 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 Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MPFR Library; see the file COPYING.LESSER.  If not, see
+https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
+51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+#define MPFR_NEED_LONGLONG_H  /* for count_leading_zeros */
+#include "mpfr-impl.h"
+
+/* count the number of significant bits of n, i.e.,
+   nbits(unsigned long) - count_leading_zeros (n) */
+int
+mpfr_nbits_ulong (unsigned long n)
+{
+  int cnt;
+
+  MPFR_ASSERTD (n > 0);
+
+#ifdef MPFR_LONG_WITHIN_LIMB
+
+  count_leading_zeros (cnt, (mp_limb_t) n);
+  cnt = GMP_NUMB_BITS - cnt;
+
+#else
+
+  cnt = 0;
+
+  while (n >= 0x10000)
+    {
+      n >>= 16;
+      cnt += 16;
+    }
+
+  MPFR_ASSERTD (n <= 0xffff);
+
+  if (n >= 0x100)
+    {
+      n >>= 8;
+      cnt += 8;
+    }
+
+  MPFR_ASSERTD (n <= 0xff);
+
+  if (n >= 0x10)
+    {
+      n >>= 4;
+      cnt += 4;
+    }
+
+  MPFR_ASSERTD (n <= 0xf);
+
+  if (n >= 4)
+    {
+      n >>= 2;
+      cnt += 2;
+    }
+
+  MPFR_ASSERTD (n <= 3);
+
+  /* now n = 1, 2, or 3 */
+  cnt += 1 + (n >= 2);
+
+#endif
+
+  MPFR_ASSERTD (cnt >= 0);
+  return cnt;
+}