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/* $OpenBSD: byte_swap_2.S,v 1.3 1996/11/13 22:05:03 niklas Exp $ */
/* $NetBSD: byte_swap_2.S,v 1.2 1996/10/17 03:08:08 cgd Exp $ */
/*
* Copyright (c) 1996 Carnegie-Mellon University.
* All rights reserved.
*
* Author: Chris G. Demetriou
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
#include <machine/asm.h>
#if defined(LIBC_SCCS)
.text
.asciz "$OpenBSD: byte_swap_2.S,v 1.3 1996/11/13 22:05:03 niklas Exp $"
#endif
#ifndef NAME
#define NAME byte_swap_2
#endif
/*
* Byte-swap a 2-byte quantity. (Convert 0x0123 to 0x2301.)
*
* Argument is an unsigned 2-byte integer (u_int16_t).
*/
LEAF(NAME, 1) /* a0 contains 0x0123 */
extbl a0, 0, t0 /* t0 = 0x 23 */
extbl a0, 1, t1 /* t1 = 0x 01 */
sll t0, 8, t0 /* t1 = 0x23 */
or t0, t1, v0 /* v0 = 0x2301 */
RET
END(NAME)
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