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[gnulib.git]
/
lib
/
gcd.c
diff --git
a/lib/gcd.c
b/lib/gcd.c
index
4d9e88f
..
3562de5
100644
(file)
--- a/
lib/gcd.c
+++ b/
lib/gcd.c
@@
-1,11
+1,11
@@
/* Arithmetic.
/* Arithmetic.
- Copyright (C) 2001 Free Software Foundation, Inc.
- Written by Bruno Haible <
haible@clisp.cons
.org>, 2001.
+ Copyright (C) 2001
-2002, 2006
Free Software Foundation, Inc.
+ Written by Bruno Haible <
bruno@clisp
.org>, 2001.
- This program is free software
;
you can redistribute it and/or modify
+ 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
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version
2, or (at your option)
- any later version.
+ 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
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
@@
-13,19
+13,24
@@
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
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, write to the Free Software Foundation,
- Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+#include <config.h>
+
+/* This file can also be used to define gcd functions for other unsigned
+ types, such as 'unsigned long long' or 'uintmax_t'. */
+#ifndef WORD_T
/* Specification. */
/* Specification. */
-#include "gcd.h"
+# include "gcd.h"
+# define WORD_T unsigned long
+# define GCD gcd
+#endif
#include <stdlib.h>
/* Return the greatest common divisor of a > 0 and b > 0. */
#include <stdlib.h>
/* Return the greatest common divisor of a > 0 and b > 0. */
-unsigned int
-gcd (a, b)
- unsigned int a;
- unsigned int b;
+WORD_T
+GCD (WORD_T a, WORD_T b)
{
/* Why no division, as in Euclid's algorithm? Because in Euclid's algorithm
the division result floor(a/b) or floor(b/a) is very often = 1 or = 2,
{
/* Why no division, as in Euclid's algorithm? Because in Euclid's algorithm
the division result floor(a/b) or floor(b/a) is very often = 1 or = 2,
@@
-35,7
+40,7
@@
gcd (a, b)
bit in a single instruction, and the algorithm uses fewer variables than
Euclid's algorithm. */
bit in a single instruction, and the algorithm uses fewer variables than
Euclid's algorithm. */
-
unsigned int
c = a | b;
+
WORD_T
c = a | b;
c = c ^ (c - 1);
/* c = largest power of 2 that divides a and b. */
c = c ^ (c - 1);
/* c = largest power of 2 that divides a and b. */