Statistics
| Branch: | Revision:

ffmpeg / libavutil / bswap.h @ c696a863

History | View | Annotate | Download (3.29 KB)

1
/*
2
 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3
 *
4
 * This file is part of FFmpeg.
5
 *
6
 * FFmpeg is free software; you can redistribute it and/or
7
 * modify it under the terms of the GNU Lesser General Public
8
 * License as published by the Free Software Foundation; either
9
 * version 2.1 of the License, or (at your option) any later version.
10
 *
11
 * FFmpeg is distributed in the hope that it will be useful,
12
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14
 * Lesser General Public License for more details.
15
 *
16
 * You should have received a copy of the GNU Lesser General Public
17
 * License along with FFmpeg; if not, write to the Free Software
18
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19
 */
20

    
21
/**
22
 * @file bswap.h
23
 * byte swapping routines
24
 */
25

    
26
#ifndef FFMPEG_BSWAP_H
27
#define FFMPEG_BSWAP_H
28

    
29
#include <stdint.h>
30
#include "config.h"
31
#include "common.h"
32

    
33
#ifdef HAVE_BYTESWAP_H
34
#include <byteswap.h>
35
#else
36

    
37
static av_always_inline av_const uint16_t bswap_16(uint16_t x)
38
{
39
#if defined(ARCH_X86)
40
    asm("rorw $8, %0" : "+r"(x));
41
#elif defined(ARCH_SH4)
42
    asm("swap.b %0,%0" : "=r"(x) : "0"(x));
43
#elif defined(HAVE_ARMV6)
44
    asm("rev16 %0, %0" : "+r"(x));
45
#else
46
    x= (x>>8) | (x<<8);
47
#endif
48
    return x;
49
}
50

    
51
static av_always_inline av_const uint32_t bswap_32(uint32_t x)
52
{
53
#if defined(ARCH_X86)
54
#ifdef HAVE_BSWAP
55
    asm("bswap   %0" : "+r" (x));
56
#else
57
    asm("rorw    $8,  %w0 \n\t"
58
        "rorl    $16, %0  \n\t"
59
        "rorw    $8,  %w0"
60
        : "+r"(x));
61
#endif
62
#elif defined(ARCH_SH4)
63
    asm("swap.b %0,%0\n"
64
        "swap.w %0,%0\n"
65
        "swap.b %0,%0\n"
66
        : "=r"(x) : "0"(x));
67
#elif defined(HAVE_ARMV6)
68
    asm("rev %0, %0" : "+r"(x));
69
#elif defined(ARCH_ARMV4L)
70
    uint32_t t;
71
    asm ("eor %1, %0, %0, ror #16 \n\t"
72
         "bic %1, %1, #0xFF0000   \n\t"
73
         "mov %0, %0, ror #8      \n\t"
74
         "eor %0, %0, %1, lsr #8  \n\t"
75
         : "+r"(x), "+r"(t));
76
#elif defined(ARCH_BFIN)
77
    unsigned tmp;
78
    asm("%1 = %0 >> 8 (V);      \n\t"
79
        "%0 = %0 << 8 (V);      \n\t"
80
        "%0 = %0 | %1;          \n\t"
81
        "%0 = PACK(%0.L, %0.H); \n\t"
82
        : "+d"(x), "=&d"(tmp));
83
#else
84
    x= ((x<<8)&0xFF00FF00) | ((x>>8)&0x00FF00FF);
85
    x= (x>>16) | (x<<16);
86
#endif
87
    return x;
88
}
89

    
90
static inline uint64_t av_const bswap_64(uint64_t x)
91
{
92
#if 0
93
    x= ((x<< 8)&0xFF00FF00FF00FF00ULL) | ((x>> 8)&0x00FF00FF00FF00FFULL);
94
    x= ((x<<16)&0xFFFF0000FFFF0000ULL) | ((x>>16)&0x0000FFFF0000FFFFULL);
95
    return (x>>32) | (x<<32);
96
#elif defined(ARCH_X86_64)
97
  asm("bswap  %0": "=r" (x) : "0" (x));
98
  return x;
99
#else
100
    union {
101
        uint64_t ll;
102
        uint32_t l[2];
103
    } w, r;
104
    w.ll = x;
105
    r.l[0] = bswap_32 (w.l[1]);
106
    r.l[1] = bswap_32 (w.l[0]);
107
    return r.ll;
108
#endif
109
}
110

    
111
#endif  /* !HAVE_BYTESWAP_H */
112

    
113
// be2me ... BigEndian to MachineEndian
114
// le2me ... LittleEndian to MachineEndian
115

    
116
#ifdef WORDS_BIGENDIAN
117
#define be2me_16(x) (x)
118
#define be2me_32(x) (x)
119
#define be2me_64(x) (x)
120
#define le2me_16(x) bswap_16(x)
121
#define le2me_32(x) bswap_32(x)
122
#define le2me_64(x) bswap_64(x)
123
#else
124
#define be2me_16(x) bswap_16(x)
125
#define be2me_32(x) bswap_32(x)
126
#define be2me_64(x) bswap_64(x)
127
#define le2me_16(x) (x)
128
#define le2me_32(x) (x)
129
#define le2me_64(x) (x)
130
#endif
131

    
132
#endif /* FFMPEG_BSWAP_H */