bswap.h 1.81 KB
Newer Older
1
/*
2
 * This file is part of Libav.
3
 *
4
 * Libav is free software; you can redistribute it and/or
5 6 7 8
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
9
 * Libav is distributed in the hope that it will be useful,
10 11 12 13 14
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
15
 * License along with Libav; if not, write to the Free Software
16 17 18 19 20 21 22 23
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef AVUTIL_ARM_BSWAP_H
#define AVUTIL_ARM_BSWAP_H

#include <stdint.h>
#include "config.h"
24
#include "libavutil/attributes.h"
25

26 27 28
#ifdef __ARMCC_VERSION

#if HAVE_ARMV6
29 30
#define av_bswap32 av_bswap32
static av_always_inline av_const uint32_t av_bswap32(uint32_t x)
31 32 33 34 35
{
    return __rev(x);
}
#endif /* HAVE_ARMV6 */

36
#elif HAVE_INLINE_ASM
37

38
#if HAVE_ARMV6_INLINE
39 40
#define av_bswap16 av_bswap16
static av_always_inline av_const unsigned av_bswap16(unsigned x)
41 42 43 44 45 46
{
    __asm__("rev16 %0, %0" : "+r"(x));
    return x;
}
#endif

47
#if !AV_GCC_VERSION_AT_LEAST(4,5)
48 49
#define av_bswap32 av_bswap32
static av_always_inline av_const uint32_t av_bswap32(uint32_t x)
50
{
51
#if HAVE_ARMV6_INLINE
52 53 54 55 56 57 58 59
    __asm__("rev %0, %0" : "+r"(x));
#else
    uint32_t t;
    __asm__ ("eor %1, %0, %0, ror #16 \n\t"
             "bic %1, %1, #0xFF0000   \n\t"
             "mov %0, %0, ror #8      \n\t"
             "eor %0, %0, %1, lsr #8  \n\t"
             : "+r"(x), "=&r"(t));
60
#endif /* HAVE_ARMV6_INLINE */
61 62
    return x;
}
63
#endif /* !AV_GCC_VERSION_AT_LEAST(4,5) */
64

65 66
#endif /* __ARMCC_VERSION */

67
#endif /* AVUTIL_ARM_BSWAP_H */