/* $NetBSD: byte_swap_4.S,v 1.3 2009/12/14 00:39:00 matt Exp $ */ /*- * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Ralph Campbell. * * 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. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 <mips/asm.h> #if defined(LIBC_SCCS) && !defined(lint) #if 0 RCSID("from: @(#)htonl.s 8.1 (Berkeley) 6/4/93") #else RCSID("$NetBSD: byte_swap_4.S,v 1.3 2009/12/14 00:39:00 matt Exp $") #endif #endif /* LIBC_SCCS and not lint */ #undef _LOCORE #define _LOCORE /* XXX not really, just assembly-code source */ #include <machine/endian.h> #if defined(_KERNEL) || defined(_STANDALONE) #define BSWAP32_NAME bswap32 #else #define BSWAP32_NAME __bswap32 #endif NLEAF(BSWAP32_NAME) # a0 = 0x11223344, return 0x44332211 #if BYTE_ORDER == LITTLE_ENDIAN ALEAF(htonl) # a0 = 0x11223344, return 0x44332211 ALEAF(ntohl) #endif #if (__mips == 32 || __mips == 64) && __mips_isa_rev == 2 /* * If we are on MIPS32R2 or MIPS64R2 it's much easier */ wsbh a0, a0 # word swap bytes within halfwords rotr v0, a0, 16 # rotate word 16bits j ra #else srl v1, a0, 24 # v1 = 0x00000011 sll v0, a0, 24 # v0 = 0x44000000 or v0, v0, v1 and v1, a0, 0xff00 sll v1, v1, 8 # v1 = 0x00330000 or v0, v0, v1 srl v1, a0, 8 and v1, v1, 0xff00 # v1 = 0x00002200 or v0, v0, v1 j ra #endif END(BSWAP32_NAME) #if BYTE_ORDER == BIG_ENDIAN NLEAF(htonl) # a0 = 0x11223344, return 0x44332211 ALEAF(ntohl) move v0, a0 j ra END(htonl) #endif |