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-rw-r--r--sysdeps/i386/memchr.c48
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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