1 /* $NetBSD: byte_swap_4.S,v 1.3 2009/12/14 00:39:00 matt Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Ralph Campbell. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <mips/asm.h> 36 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 RCSID("from: @(#)htonl.s 8.1 (Berkeley) 6/4/93") 40 #else 41 RCSID("$NetBSD: byte_swap_4.S,v 1.3 2009/12/14 00:39:00 matt Exp $") 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 #undef _LOCORE 46 #define _LOCORE /* XXX not really, just assembly-code source */ 47 #include <machine/endian.h> 48 49 #if defined(_KERNEL) || defined(_STANDALONE) 50 #define BSWAP32_NAME bswap32 51 #else 52 #define BSWAP32_NAME __bswap32 53 #endif 54 55 NLEAF(BSWAP32_NAME) # a0 = 0x11223344, return 0x44332211 56 #if BYTE_ORDER == LITTLE_ENDIAN 57 ALEAF(htonl) # a0 = 0x11223344, return 0x44332211 58 ALEAF(ntohl) 59 #endif 60 #if (__mips == 32 || __mips == 64) && __mips_isa_rev == 2 61 /* 62 * If we are on MIPS32R2 or MIPS64R2 it's much easier 63 */ 64 wsbh a0, a0 # word swap bytes within halfwords 65 rotr v0, a0, 16 # rotate word 16bits 66 j ra 67 #else 68 srl v1, a0, 24 # v1 = 0x00000011 69 sll v0, a0, 24 # v0 = 0x44000000 70 or v0, v0, v1 71 and v1, a0, 0xff00 72 sll v1, v1, 8 # v1 = 0x00330000 73 or v0, v0, v1 74 srl v1, a0, 8 75 and v1, v1, 0xff00 # v1 = 0x00002200 76 or v0, v0, v1 77 j ra 78 #endif 79 END(BSWAP32_NAME) 80 81 #if BYTE_ORDER == BIG_ENDIAN 82 NLEAF(htonl) # a0 = 0x11223344, return 0x44332211 83 ALEAF(ntohl) 84 move v0, a0 85 j ra 86 END(htonl) 87 #endif 88
Indexes created Sat Sep 20 22:09:52 GMT 2025