diff options
Diffstat (limited to 'lib/libc/alpha/net/byte_swap_2.S')
| -rw-r--r-- | lib/libc/alpha/net/byte_swap_2.S | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/lib/libc/alpha/net/byte_swap_2.S b/lib/libc/alpha/net/byte_swap_2.S new file mode 100644 index 0000000..fab3c58 --- /dev/null +++ b/lib/libc/alpha/net/byte_swap_2.S @@ -0,0 +1,47 @@ +/* $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> + +#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) |
