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/* memchr (str, ch, n) -- Return pointer to first occurrence of CH in STR less
than N.
For Intel 80x86, x>=3.
Copyright (C) 1991, 1992, 1993 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>
#ifdef __GNUC__
PTR
DEFUN(memchr, (str, c, len),
CONST PTR str AND int c AND size_t len)
{
PTR retval;
asm("cld\n" /* Search forward. */
"testl %1,%1\n" /* Clear Z flag, to handle LEN == 0. */
/* Some old versions of gas need `repne' instead of `repnz'. */
"repnz\n" /* Search for C in al. */
"scasb\n"
"movl %2,%0\n" /* Set %0 to 0 (without affecting Z flag). */
"jnz done\n" /* Jump if we found nothing equal to C. */
"leal -1(%1),%0\n" /* edi has been incremented. Return edi-1. */
"done:" :
"=a" (retval), "=D" (str), "=c" (len) :
"0" (c), "1" (str), "2" (len));
return retval;
}
#else
#include <sysdeps/generic/memchr.c>
#endif
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