blob: acd834eb3838b87c16aa8dccf1573ceedbcfd933 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
/* ffs -- find first set bit in a word, counted from least significant end.
For Intel 80x86, x>=6.
This file is part of the GNU C Library.
Copyright (C) 1991-2020 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 ffs
#ifdef __GNUC__
int
__ffs (int x)
{
int cnt;
int tmp;
asm ("bsfl %2,%0\n" /* Count low bits in X and store in %1. */
"cmovel %1,%0\n" /* If number was zero, use -1 as result. */
: "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
return cnt + 1;
}
weak_alias (__ffs, ffs)
libc_hidden_def (__ffs)
libc_hidden_builtin_def (ffs)
#undef ffsl
weak_alias (__ffs, ffsl)
#else
#include <string/ffs.c>
#endif
|
GitWeb
