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diff --git a/gnulib b/gnulib
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diff --git a/gnulib/lib/integer_length_l.c b/gnulib/lib/integer_length_l.c
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+/* integer_length_l - find most significant bit in an 'unsigned long'.
+ Copyright (C) 2011 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2011. */
+
+#include <config.h>
+
+/* Specification. */
+#include "integer_length.h"
+
+#include <limits.h>
+#include <stddef.h>
+
+#undef MIN
+#define MIN(a,b) ((a) < (b) ? (a) : (b))
+
+#ifdef USE_LONG_LONG
+# define FUNC integer_length_ll
+# define TYPE unsigned long long
+# define GCC_BUILTIN __builtin_clzll
+#else
+# define FUNC integer_length_l
+# define TYPE unsigned long
+# define GCC_BUILTIN __builtin_clzl
+#endif
+
+#define NBITS (sizeof (TYPE) * CHAR_BIT)
+
+/* Modify shift count to be in bounds, even in dead code, otherwise GCC
+ emits warnings "right shift count >= width of type". */
+#define MSC(i) MIN (i, NBITS - 1)
+
+int
+FUNC (TYPE x)
+{
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
+ if (x == 0)
+ return 0;
+ else
+ return NBITS - GCC_BUILTIN (x);
+#else
+ /* Split x into chunks, and look at one chunk after the other. */
+ if (sizeof (TYPE) > 2 * sizeof (unsigned int))
+ {
+ /* Generic loop. */
+ size_t i;
+
+ for (i = (sizeof (TYPE) - 1) / sizeof (unsigned int); i >= 2; i--)
+ {
+ unsigned int y = x >> (i * sizeof (unsigned int) * CHAR_BIT);
+ if (y != 0)
+ return i * sizeof (unsigned int) * CHAR_BIT + integer_length (y);
+ }
+ }
+
+ /* Unrolled the last 2 loop rounds. */
+ /* i = 1 */
+ if (sizeof (TYPE) > 1 * sizeof (unsigned int))
+ {
+ unsigned int y = x >> MSC (1 * sizeof (unsigned int) * CHAR_BIT);
+ if (y != 0)
+ return 1 * sizeof (unsigned int) * CHAR_BIT + integer_length (y);
+ }
+
+ /* i = 0 */
+ return integer_length ((unsigned int) x);
+#endif
+}