glibc/sysdeps/m68k/ffs.c

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/* ffs -- find first set bit in a word, counted from least significant end.
For mc68020, mc68030, mc68040.
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This file is part of the GNU C Library.
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Copyright (C) 1991, 1992, 1997, 1998, 2004 Free Software Foundation, Inc.
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Contributed by Torbjorn Granlund (tege@sics.se).
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
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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
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
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#define ffsl __something_else
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#include <string.h>
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#undef ffs
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#if defined (__GNUC__) && defined (__mc68020__)
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int
__ffs (x)
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int x;
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{
int cnt;
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asm ("bfffo %1{#0:#0},%0" : "=d" (cnt) : "dm" (x & -x));
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return 32 - cnt;
}
weak_alias (__ffs, ffs)
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libc_hidden_builtin_def (ffs)
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#undef ffsl
weak_alias (__ffs, ffsl)
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#else
#include <sysdeps/generic/ffs.c>
#endif