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/* strlen -- determine the length of a string.
For Intel 80x86, x>=3.
Copyright (C) 1991, 1992, 1993, 1996 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 <string.h>
size_t
strlen (const char *str)
{
int cnt;
asm("cld\n" /* Search forward. */
/* Some old versions of gas need `repne' instead of `repnz'. */
"repnz\n" /* Look for a zero byte. */
"scasb" /* %0, %1, %3 */ :
"=c" (cnt) : "D" (str), "0" (-1), "a" (0));
return -2 - cnt;
}
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