/* $NetBSD: byte_swap_2.S,v 1.6 2013/08/19 03:44:18 matt Exp $ */ /*- * Copyright (c) 1999 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Charles M. Hannum. * * 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> #if defined(_KERNEL) || defined(_STANDALONE) #define FUNC _C_LABEL(bswap16) #else #define FUNC _C_LABEL(__bswap16) #endif ENTRY(FUNC) #ifdef _ARM_ARCH_6 rev16 r0, r0 #elif !defined(__thumb__) and r1, r0, #0xff mov r0, r0, lsr #8 orr r0, r0, r1, lsl #8 #else movs r2, #0xff movs r1, r0 ands r1, r1, r2 lsls r1, r1, #8 lsrs r0, r0, #8 ands r0, r0, r2 orrs r0, r0, r1 #endif RET END(FUNC) #if BYTE_ORDER == LITTLE_ENDIAN STRONG_ALIAS(_C_LABEL(ntohs), FUNC) STRONG_ALIAS(_C_LABEL(htons), FUNC) #endif |