/* $NetBSD: strcat.S,v 1.1 2014/08/10 05:47:35 matt Exp $ */

/*-
 * Copyright (c) 2014 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Matt Thomas of 3am Software Foundry.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * 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.
 */

#include <machine/asm.h>

RCSID("$NetBSD: strcat.S,v 1.1 2014/08/10 05:47:35 matt Exp $")

/*
 * Implementation of strcat using strlen/strcpy.
 */
ENTRY(strcat)
        stp     x29, x30, [sp, #-32]!   /* save fp, lr */
        mov     x29, sp                 /* init fp */
        stp     x27, x28, [x29, #16]    /* save registers */

        mov     x27, x0                 /* save dst */
        mov     x28, x1                 /* save append */

        bl      _C_LABEL(strlen)        /* find length of dst */

        add     x0, x0, x27             /* add to dst pointer */
        mov     x1, x28                 /* fetch append */
        bl      _C_LABEL(strcpy)        /* append string */

        mov     x0, x27                 /* restore dst as return value */
        ldp     x27, x28, [x29, #16]    /* save registers */
        ldp     x29, x30, [sp], #32     /* save fp, lr; pop stack */
        ret
END(strcat)