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/* ffsll -- find first set bit in a word, counted from least significant end.
For AMD x86-64.
This file is part of the GNU C Library.
Copyright (C) 1991-2021 Free Software Foundation, Inc.
Contributed by Ulrich Drepper <drepper@cygnus.com>.
The GNU C 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 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#define ffsl __something_else
#include <string.h>
#undef ffsll
int
ffsll (long long int x)
{
long long int cnt;
asm ("mov $-1,%k0\n" /* Initialize cnt to -1. */
"bsf %1,%0\n" /* Count low bits in x and store in cnt. */
"inc %k0\n" /* Increment cnt by 1. */
: "=&r" (cnt) : "r" (x));
return cnt;
}
#ifndef __ILP32__
#undef ffsl
weak_alias (ffsll, ffsl)
#endif
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