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-rw-r--r--sysdeps/i386/ffs.c45
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diff --git a/sysdeps/i386/ffs.c b/sysdeps/i386/ffs.c
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+/* ffs -- find first set bit in a word, counted from least significant end.
+   For Intel 80x86, x>=3.
+   Copyright (C) 1991, 1992, 1993, 1994 Free Software Foundation, Inc.
+   Contributed by Torbjorn Granlund (tege@sics.se).
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <ansidecl.h>
+#include <string.h>
+
+#undef	ffs
+
+#ifdef	__GNUC__
+
+int
+DEFUN(ffs, (x), int x)
+{
+  int cnt;
+  int tmp;
+
+  asm ("xorl %0,%0\n"		/* Set CNT to zero.  */
+       "bsfl %2,%1\n"		/* Count low bits in X and store in %1.  */
+       "jz nonzero\n"		/* Jump if OK, i.e. X was non-zero.  */
+       "leal 1(%1),%0\n"	/* Return bsfl-result plus one on %0.  */
+       "nonzero:" : "=&a" (cnt), "=r" (tmp) : "rm" (x));
+
+  return cnt;
+}
+
+#else
+#include <sysdeps/generic/ffs.c>
+#endif