# strchr.S

/* Copyright (c) 2002, 2007 Marek Michalkiewicz

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modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright
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* Redistributions in binary form must reproduce the above copyright
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the documentation and/or other materials provided with the
distribution.
* Neither the name of the copyright holders nor the names of
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE. */

/* $Id$ */

/** \file */

/** \ingroup avr_string
\fn char *strchr(const char *src, int val)
\brief Locate character in string.

The strchr() function returns a pointer to the first occurrence of
the character \p val in the string \p src.

Here "character" means "byte" - these functions do not work with
wide or multi-byte characters.

\returns The strchr() function returns a pointer to the matched

#if !defined(__AVR_TINY__)

#if !defined(__DOXYGEN__)

#include "macros.inc"

#define src_hi r25
#define src_lo r24
; #define val_hi r23
#define val_lo r22

#define ret_hi r25
#define ret_lo r24

ASSEMBLY_CLIB_SECTION
.global _U(strchr)
.type   _U(strchr), @function
_U(strchr):
X_movw  ZL, src_lo
.L_strchr_loop:
ld      ret_lo, Z+
cp      ret_lo, val_lo
breq    .L_strchr_found
tst     ret_lo
brne    .L_strchr_loop