1 /*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19 /**
20 * @file
21 * byte swapping routines
22 */
23
24 #ifndef AVUTIL_X86_BSWAP_H
25 #define AVUTIL_X86_BSWAP_H
26
27 #include <stdint.h>
28 #if defined(_MSC_VER)
29 #include <stdlib.h>
30 #include <intrin.h>
31 #endif
32 #include "config.h"
33 #include "libavutil/attributes.h"
34
35 #if defined(_MSC_VER)
36
37 #define av_bswap16 av_bswap16
av_bswap16(uint16_t x)38 static av_always_inline av_const uint16_t av_bswap16(uint16_t x)
39 {
40 return _rotr16(x, 8);
41 }
42
43 #define av_bswap32 av_bswap32
av_bswap32(uint32_t x)44 static av_always_inline av_const uint32_t av_bswap32(uint32_t x)
45 {
46 return _byteswap_ulong(x);
47 }
48
49 #if ARCH_X86_64
50 #define av_bswap64 av_bswap64
av_bswap64(uint64_t x)51 static inline uint64_t av_const av_bswap64(uint64_t x)
52 {
53 return _byteswap_uint64(x);
54 }
55 #endif
56
57
58 #elif HAVE_INLINE_ASM
59
60 #if AV_GCC_VERSION_AT_MOST(4,0)
61 #define av_bswap16 av_bswap16
av_bswap16(unsigned x)62 static av_always_inline av_const unsigned av_bswap16(unsigned x)
63 {
64 __asm__("rorw $8, %w0" : "+r"(x));
65 return x;
66 }
67 #endif /* AV_GCC_VERSION_AT_MOST(4,0) */
68
69 #if AV_GCC_VERSION_AT_MOST(4,4) || defined(__INTEL_COMPILER)
70 #define av_bswap32 av_bswap32
av_bswap32(uint32_t x)71 static av_always_inline av_const uint32_t av_bswap32(uint32_t x)
72 {
73 __asm__("bswap %0" : "+r" (x));
74 return x;
75 }
76
77 #if ARCH_X86_64
78 #define av_bswap64 av_bswap64
av_bswap64(uint64_t x)79 static inline uint64_t av_const av_bswap64(uint64_t x)
80 {
81 __asm__("bswap %0": "=r" (x) : "0" (x));
82 return x;
83 }
84 #endif
85 #endif /* AV_GCC_VERSION_AT_MOST(4,4) */
86
87 #endif /* HAVE_INLINE_ASM */
88 #endif /* AVUTIL_X86_BSWAP_H */
89