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Akinobu Mitaa5cfc1e2006-12-08 02:36:25 -08001#ifndef _LINUX_BITREV_H
2#define _LINUX_BITREV_H
3
4#include <linux/types.h>
5
Yalin Wang556d2f02014-11-03 03:01:03 +01006#ifdef CONFIG_HAVE_ARCH_BITREVERSE
7#include <asm/bitrev.h>
Akinobu Mitaa5cfc1e2006-12-08 02:36:25 -08008
Yalin Wang556d2f02014-11-03 03:01:03 +01009#define __bitrev32 __arch_bitrev32
10#define __bitrev16 __arch_bitrev16
11#define __bitrev8 __arch_bitrev8
12
13#else
14extern u8 const byte_rev_table[256];
15static inline u8 __bitrev8(u8 byte)
Akinobu Mitaa5cfc1e2006-12-08 02:36:25 -080016{
17 return byte_rev_table[byte];
18}
19
Yalin Wang556d2f02014-11-03 03:01:03 +010020static inline u16 __bitrev16(u16 x)
21{
22 return (__bitrev8(x & 0xff) << 8) | __bitrev8(x >> 8);
23}
Akinobu Mitaa5cfc1e2006-12-08 02:36:25 -080024
Yalin Wang556d2f02014-11-03 03:01:03 +010025static inline u32 __bitrev32(u32 x)
26{
27 return (__bitrev16(x & 0xffff) << 16) | __bitrev16(x >> 16);
28}
29
30#endif /* CONFIG_HAVE_ARCH_BITREVERSE */
31
32#define __constant_bitrev32(x) \
33({ \
34 u32 __x = x; \
35 __x = (__x >> 16) | (__x << 16); \
36 __x = ((__x & (u32)0xFF00FF00UL) >> 8) | ((__x & (u32)0x00FF00FFUL) << 8); \
37 __x = ((__x & (u32)0xF0F0F0F0UL) >> 4) | ((__x & (u32)0x0F0F0F0FUL) << 4); \
38 __x = ((__x & (u32)0xCCCCCCCCUL) >> 2) | ((__x & (u32)0x33333333UL) << 2); \
39 __x = ((__x & (u32)0xAAAAAAAAUL) >> 1) | ((__x & (u32)0x55555555UL) << 1); \
40 __x; \
41})
42
43#define __constant_bitrev16(x) \
44({ \
45 u16 __x = x; \
46 __x = (__x >> 8) | (__x << 8); \
47 __x = ((__x & (u16)0xF0F0U) >> 4) | ((__x & (u16)0x0F0FU) << 4); \
48 __x = ((__x & (u16)0xCCCCU) >> 2) | ((__x & (u16)0x3333U) << 2); \
49 __x = ((__x & (u16)0xAAAAU) >> 1) | ((__x & (u16)0x5555U) << 1); \
50 __x; \
51})
52
53#define __constant_bitrev8(x) \
54({ \
55 u8 __x = x; \
56 __x = (__x >> 4) | (__x << 4); \
57 __x = ((__x & (u8)0xCCU) >> 2) | ((__x & (u8)0x33U) << 2); \
58 __x = ((__x & (u8)0xAAU) >> 1) | ((__x & (u8)0x55U) << 1); \
59 __x; \
60})
61
62#define bitrev32(x) \
63({ \
64 u32 __x = x; \
65 __builtin_constant_p(__x) ? \
66 __constant_bitrev32(__x) : \
67 __bitrev32(__x); \
68})
69
70#define bitrev16(x) \
71({ \
72 u16 __x = x; \
73 __builtin_constant_p(__x) ? \
74 __constant_bitrev16(__x) : \
75 __bitrev16(__x); \
76 })
77
78#define bitrev8(x) \
79({ \
80 u8 __x = x; \
81 __builtin_constant_p(__x) ? \
82 __constant_bitrev8(__x) : \
83 __bitrev8(__x) ; \
84 })
Akinobu Mitaa5cfc1e2006-12-08 02:36:25 -080085#endif /* _LINUX_BITREV_H */