FFmpeg
bswap.h
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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
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
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
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 #ifdef __INTEL_COMPILER
61 #define av_bswap32 av_bswap32
62 static av_always_inline av_const uint32_t av_bswap32(uint32_t x)
63 {
64  __asm__("bswap %0" : "+r" (x));
65  return x;
66 }
67 
68 #if ARCH_X86_64
69 #define av_bswap64 av_bswap64
70 static inline uint64_t av_const av_bswap64(uint64_t x)
71 {
72  __asm__("bswap %0": "=r" (x) : "0" (x));
73  return x;
74 }
75 #endif
76 #endif /* __INTEL_COMPILER */
77 
78 #endif /* HAVE_INLINE_ASM */
79 #endif /* AVUTIL_X86_BSWAP_H */
av_const
#define av_const
Definition: attributes.h:84
av_bswap32
#define av_bswap32
Definition: bswap.h:47
attributes.h
av_always_inline
#define av_always_inline
Definition: attributes.h:49
__asm__
__asm__(".macro parse_r var r\n\t" "\\var = -1\n\t" _IFC_REG(0) _IFC_REG(1) _IFC_REG(2) _IFC_REG(3) _IFC_REG(4) _IFC_REG(5) _IFC_REG(6) _IFC_REG(7) _IFC_REG(8) _IFC_REG(9) _IFC_REG(10) _IFC_REG(11) _IFC_REG(12) _IFC_REG(13) _IFC_REG(14) _IFC_REG(15) _IFC_REG(16) _IFC_REG(17) _IFC_REG(18) _IFC_REG(19) _IFC_REG(20) _IFC_REG(21) _IFC_REG(22) _IFC_REG(23) _IFC_REG(24) _IFC_REG(25) _IFC_REG(26) _IFC_REG(27) _IFC_REG(28) _IFC_REG(29) _IFC_REG(30) _IFC_REG(31) ".iflt \\var\n\t" ".error \"Unable to parse register name \\r\"\n\t" ".endif\n\t" ".endm")
av_bswap16
#define av_bswap16
Definition: bswap.h:28
av_bswap64
static uint64_t av_const av_bswap64(uint64_t x)
Definition: bswap.h:69