master
1/* $NetBSD: byte_swap.h,v 1.4 2017/01/17 11:09:36 rin Exp $ */
2
3/*-
4 * Copyright (c) 2014 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Matt Thomas of 3am Software Foundry.
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 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef _ARM_BYTE_SWAP_H_
33#define _ARM_BYTE_SWAP_H_
34
35#ifdef __aarch64__
36
37#ifdef _LOCORE
38
39#define BSWAP16(_src, _dst) \
40 rev16 _dst, _src
41#define BSWAP32(_src, _dst) \
42 rev _dst, _src
43#define BSWAP64(_src, _dst) \
44 rev _dst, _src
45
46#else
47
48#ifdef __GNUC__
49#include <sys/types.h>
50__BEGIN_DECLS
51
52#define __BYTE_SWAP_U64_VARIABLE __byte_swap_u64_variable
53static __inline uint64_t
54__byte_swap_u64_variable(uint64_t v)
55{
56 if (!__builtin_constant_p(v)) {
57 __asm("rev\t%x0, %x1" : "=r" (v) : "0" (v));
58 return v;
59 }
60
61 v = ((v & 0x000000ff) << (56 - 0)) | ((v >> (56 - 0)) & 0x000000ff)
62 | ((v & 0x0000ff00) << (48 - 8)) | ((v >> (48 - 8)) & 0x0000ff00)
63 | ((v & 0x00ff0000) << (40 - 16)) | ((v >> (40 - 16)) & 0x00ff0000)
64 | ((v & 0xff000000) << (32 - 24)) | ((v >> (32 - 24)) & 0xff000000);
65
66 return v;
67}
68
69#define __BYTE_SWAP_U32_VARIABLE __byte_swap_u32_variable
70static __inline uint32_t
71__byte_swap_u32_variable(uint32_t v)
72{
73 if (!__builtin_constant_p(v)) {
74 __asm("rev\t%w0, %w1" : "=r" (v) : "0" (v));
75 return v;
76 }
77
78 v = ((v & 0x00ff) << (24 - 0)) | ((v >> (24 - 0)) & 0x00ff)
79 | ((v & 0xff00) << (16 - 8)) | ((v >> (16 - 8)) & 0xff00);
80
81 return v;
82}
83
84#define __BYTE_SWAP_U16_VARIABLE __byte_swap_u16_variable
85static __inline uint16_t
86__byte_swap_u16_variable(uint16_t v)
87{
88
89 if (!__builtin_constant_p(v)) {
90 uint32_t v32 = v;
91 __asm("rev16\t%w0, %w1" : "=r" (v32) : "0" (v32));
92 return (uint16_t)v32;
93 }
94
95 v &= 0xffff;
96 v = (uint16_t)((v >> 8) | (v << 8));
97
98 return v;
99}
100
101__END_DECLS
102#endif
103
104#endif /* _LOCORE */
105
106#elif defined(__arm__)
107
108#include <arm/asm.h>
109
110#endif
111
112#endif /* _ARM_BYTE_SWAP_H_ */