From 28f540f45bbacd939bfd07f213bcad2bf730b1bf Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Sat, 18 Feb 1995 01:27:10 +0000 Subject: initial import --- sysdeps/i386/memchr.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 sysdeps/i386/memchr.c (limited to 'sysdeps/i386/memchr.c') diff --git a/sysdeps/i386/memchr.c b/sysdeps/i386/memchr.c new file mode 100644 index 0000000000..ff0f8d9044 --- /dev/null +++ b/sysdeps/i386/memchr.c @@ -0,0 +1,48 @@ +/* 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 +#include + +#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 +#endif -- cgit v1.2.3