xref: /minix3/common/lib/libc/arch/aarch64/string/strcat.S (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1*0a6a1f1dSLionel Sambuc/* $NetBSD: strcat.S,v 1.1 2014/08/10 05:47:35 matt Exp $ */
2*0a6a1f1dSLionel Sambuc
3*0a6a1f1dSLionel Sambuc/*-
4*0a6a1f1dSLionel Sambuc * Copyright (c) 2014 The NetBSD Foundation, Inc.
5*0a6a1f1dSLionel Sambuc * All rights reserved.
6*0a6a1f1dSLionel Sambuc *
7*0a6a1f1dSLionel Sambuc * This code is derived from software contributed to The NetBSD Foundation
8*0a6a1f1dSLionel Sambuc * by Matt Thomas of 3am Software Foundry.
9*0a6a1f1dSLionel Sambuc *
10*0a6a1f1dSLionel Sambuc * Redistribution and use in source and binary forms, with or without
11*0a6a1f1dSLionel Sambuc * modification, are permitted provided that the following conditions
12*0a6a1f1dSLionel Sambuc * are met:
13*0a6a1f1dSLionel Sambuc * 1. Redistributions of source code must retain the above copyright
14*0a6a1f1dSLionel Sambuc *    notice, this list of conditions and the following disclaimer.
15*0a6a1f1dSLionel Sambuc * 2. Redistributions in binary form must reproduce the above copyright
16*0a6a1f1dSLionel Sambuc *    notice, this list of conditions and the following disclaimer in the
17*0a6a1f1dSLionel Sambuc *    documentation and/or other materials provided with the distribution.
18*0a6a1f1dSLionel Sambuc *
19*0a6a1f1dSLionel Sambuc * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20*0a6a1f1dSLionel Sambuc * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21*0a6a1f1dSLionel Sambuc * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22*0a6a1f1dSLionel Sambuc * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23*0a6a1f1dSLionel Sambuc * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24*0a6a1f1dSLionel Sambuc * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25*0a6a1f1dSLionel Sambuc * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26*0a6a1f1dSLionel Sambuc * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27*0a6a1f1dSLionel Sambuc * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28*0a6a1f1dSLionel Sambuc * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29*0a6a1f1dSLionel Sambuc * POSSIBILITY OF SUCH DAMAGE.
30*0a6a1f1dSLionel Sambuc */
31*0a6a1f1dSLionel Sambuc
32*0a6a1f1dSLionel Sambuc#include <machine/asm.h>
33*0a6a1f1dSLionel Sambuc
34*0a6a1f1dSLionel SambucRCSID("$NetBSD: strcat.S,v 1.1 2014/08/10 05:47:35 matt Exp $")
35*0a6a1f1dSLionel Sambuc
36*0a6a1f1dSLionel Sambuc/*
37*0a6a1f1dSLionel Sambuc * Implementation of strcat using strlen/strcpy.
38*0a6a1f1dSLionel Sambuc */
39*0a6a1f1dSLionel SambucENTRY(strcat)
40*0a6a1f1dSLionel Sambuc	stp	x29, x30, [sp, #-32]!	/* save fp, lr */
41*0a6a1f1dSLionel Sambuc	mov	x29, sp			/* init fp */
42*0a6a1f1dSLionel Sambuc	stp	x27, x28, [x29, #16]	/* save registers */
43*0a6a1f1dSLionel Sambuc
44*0a6a1f1dSLionel Sambuc	mov	x27, x0			/* save dst */
45*0a6a1f1dSLionel Sambuc	mov	x28, x1			/* save append */
46*0a6a1f1dSLionel Sambuc
47*0a6a1f1dSLionel Sambuc	bl	_C_LABEL(strlen)	/* find length of dst */
48*0a6a1f1dSLionel Sambuc
49*0a6a1f1dSLionel Sambuc	add	x0, x0, x27		/* add to dst pointer */
50*0a6a1f1dSLionel Sambuc	mov	x1, x28			/* fetch append */
51*0a6a1f1dSLionel Sambuc	bl	_C_LABEL(strcpy)	/* append string */
52*0a6a1f1dSLionel Sambuc
53*0a6a1f1dSLionel Sambuc	mov	x0, x27			/* restore dst as return value */
54*0a6a1f1dSLionel Sambuc	ldp	x27, x28, [x29, #16]	/* save registers */
55*0a6a1f1dSLionel Sambuc	ldp	x29, x30, [sp], #32	/* save fp, lr; pop stack */
56*0a6a1f1dSLionel Sambuc	ret
57*0a6a1f1dSLionel SambucEND(strcat)
58