xref: /minix3/common/lib/libc/arch/mips/gen/byte_swap_4.S (revision b6cbf7203b080219de306404f8022a65b7884f33)
1*b6cbf720SGianluca Guida/*	$NetBSD: byte_swap_4.S,v 1.3 2009/12/14 00:39:00 matt Exp $	*/
2*b6cbf720SGianluca Guida
3*b6cbf720SGianluca Guida/*-
4*b6cbf720SGianluca Guida * Copyright (c) 1991, 1993
5*b6cbf720SGianluca Guida *	The Regents of the University of California.  All rights reserved.
6*b6cbf720SGianluca Guida *
7*b6cbf720SGianluca Guida * This code is derived from software contributed to Berkeley by
8*b6cbf720SGianluca Guida * Ralph Campbell.
9*b6cbf720SGianluca Guida *
10*b6cbf720SGianluca Guida * Redistribution and use in source and binary forms, with or without
11*b6cbf720SGianluca Guida * modification, are permitted provided that the following conditions
12*b6cbf720SGianluca Guida * are met:
13*b6cbf720SGianluca Guida * 1. Redistributions of source code must retain the above copyright
14*b6cbf720SGianluca Guida *    notice, this list of conditions and the following disclaimer.
15*b6cbf720SGianluca Guida * 2. Redistributions in binary form must reproduce the above copyright
16*b6cbf720SGianluca Guida *    notice, this list of conditions and the following disclaimer in the
17*b6cbf720SGianluca Guida *    documentation and/or other materials provided with the distribution.
18*b6cbf720SGianluca Guida * 3. Neither the name of the University nor the names of its contributors
19*b6cbf720SGianluca Guida *    may be used to endorse or promote products derived from this software
20*b6cbf720SGianluca Guida *    without specific prior written permission.
21*b6cbf720SGianluca Guida *
22*b6cbf720SGianluca Guida * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23*b6cbf720SGianluca Guida * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24*b6cbf720SGianluca Guida * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25*b6cbf720SGianluca Guida * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26*b6cbf720SGianluca Guida * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27*b6cbf720SGianluca Guida * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28*b6cbf720SGianluca Guida * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29*b6cbf720SGianluca Guida * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30*b6cbf720SGianluca Guida * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31*b6cbf720SGianluca Guida * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32*b6cbf720SGianluca Guida * SUCH DAMAGE.
33*b6cbf720SGianluca Guida */
34*b6cbf720SGianluca Guida
35*b6cbf720SGianluca Guida#include <mips/asm.h>
36*b6cbf720SGianluca Guida
37*b6cbf720SGianluca Guida#if defined(LIBC_SCCS) && !defined(lint)
38*b6cbf720SGianluca Guida#if 0
39*b6cbf720SGianluca Guida	RCSID("from: @(#)htonl.s	8.1 (Berkeley) 6/4/93")
40*b6cbf720SGianluca Guida#else
41*b6cbf720SGianluca Guida	RCSID("$NetBSD: byte_swap_4.S,v 1.3 2009/12/14 00:39:00 matt Exp $")
42*b6cbf720SGianluca Guida#endif
43*b6cbf720SGianluca Guida#endif /* LIBC_SCCS and not lint */
44*b6cbf720SGianluca Guida
45*b6cbf720SGianluca Guida#undef _LOCORE
46*b6cbf720SGianluca Guida#define _LOCORE		/* XXX not really, just assembly-code source */
47*b6cbf720SGianluca Guida#include <machine/endian.h>
48*b6cbf720SGianluca Guida
49*b6cbf720SGianluca Guida#if defined(_KERNEL) || defined(_STANDALONE)
50*b6cbf720SGianluca Guida#define	BSWAP32_NAME	bswap32
51*b6cbf720SGianluca Guida#else
52*b6cbf720SGianluca Guida#define	BSWAP32_NAME	__bswap32
53*b6cbf720SGianluca Guida#endif
54*b6cbf720SGianluca Guida
55*b6cbf720SGianluca GuidaNLEAF(BSWAP32_NAME)			# a0 = 0x11223344, return 0x44332211
56*b6cbf720SGianluca Guida#if BYTE_ORDER == LITTLE_ENDIAN
57*b6cbf720SGianluca GuidaALEAF(htonl)				# a0 = 0x11223344, return 0x44332211
58*b6cbf720SGianluca GuidaALEAF(ntohl)
59*b6cbf720SGianluca Guida#endif
60*b6cbf720SGianluca Guida#if (__mips == 32 || __mips == 64) && __mips_isa_rev == 2
61*b6cbf720SGianluca Guida	/*
62*b6cbf720SGianluca Guida	 * If we are on MIPS32R2 or MIPS64R2 it's much easier
63*b6cbf720SGianluca Guida	 */
64*b6cbf720SGianluca Guida	wsbh	a0, a0			# word swap bytes within halfwords
65*b6cbf720SGianluca Guida	rotr	v0, a0, 16		# rotate word 16bits
66*b6cbf720SGianluca Guida	j	ra
67*b6cbf720SGianluca Guida#else
68*b6cbf720SGianluca Guida	srl	v1, a0, 24		# v1 = 0x00000011
69*b6cbf720SGianluca Guida	sll	v0, a0, 24		# v0 = 0x44000000
70*b6cbf720SGianluca Guida	or	v0, v0, v1
71*b6cbf720SGianluca Guida	and	v1, a0, 0xff00
72*b6cbf720SGianluca Guida	sll	v1, v1, 8		# v1 = 0x00330000
73*b6cbf720SGianluca Guida	or	v0, v0, v1
74*b6cbf720SGianluca Guida	srl	v1, a0, 8
75*b6cbf720SGianluca Guida	and	v1, v1, 0xff00		# v1 = 0x00002200
76*b6cbf720SGianluca Guida	or	v0, v0, v1
77*b6cbf720SGianluca Guida	j	ra
78*b6cbf720SGianluca Guida#endif
79*b6cbf720SGianluca GuidaEND(BSWAP32_NAME)
80*b6cbf720SGianluca Guida
81*b6cbf720SGianluca Guida#if BYTE_ORDER == BIG_ENDIAN
82*b6cbf720SGianluca GuidaNLEAF(htonl)				# a0 = 0x11223344, return 0x44332211
83*b6cbf720SGianluca GuidaALEAF(ntohl)
84*b6cbf720SGianluca Guida	move	v0, a0
85*b6cbf720SGianluca Guida	j	ra
86*b6cbf720SGianluca GuidaEND(htonl)
87*b6cbf720SGianluca Guida#endif
88