Linux kernel mirror (for testing)
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1#ifndef _LINUX_BITREV_H
2#define _LINUX_BITREV_H
3
4#include <linux/types.h>
5
6#ifdef CONFIG_HAVE_ARCH_BITREVERSE
7#include <asm/bitrev.h>
8
9#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)
16{
17 return byte_rev_table[byte];
18}
19
20static inline u16 __bitrev16(u16 x)
21{
22 return (__bitrev8(x & 0xff) << 8) | __bitrev8(x >> 8);
23}
24
25static 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 __bitrev8x4(x) (__bitrev32(swab32(x)))
33
34#define __constant_bitrev32(x) \
35({ \
36 u32 __x = x; \
37 __x = (__x >> 16) | (__x << 16); \
38 __x = ((__x & (u32)0xFF00FF00UL) >> 8) | ((__x & (u32)0x00FF00FFUL) << 8); \
39 __x = ((__x & (u32)0xF0F0F0F0UL) >> 4) | ((__x & (u32)0x0F0F0F0FUL) << 4); \
40 __x = ((__x & (u32)0xCCCCCCCCUL) >> 2) | ((__x & (u32)0x33333333UL) << 2); \
41 __x = ((__x & (u32)0xAAAAAAAAUL) >> 1) | ((__x & (u32)0x55555555UL) << 1); \
42 __x; \
43})
44
45#define __constant_bitrev16(x) \
46({ \
47 u16 __x = x; \
48 __x = (__x >> 8) | (__x << 8); \
49 __x = ((__x & (u16)0xF0F0U) >> 4) | ((__x & (u16)0x0F0FU) << 4); \
50 __x = ((__x & (u16)0xCCCCU) >> 2) | ((__x & (u16)0x3333U) << 2); \
51 __x = ((__x & (u16)0xAAAAU) >> 1) | ((__x & (u16)0x5555U) << 1); \
52 __x; \
53})
54
55#define __constant_bitrev8x4(x) \
56({ \
57 u32 __x = x; \
58 __x = ((__x & (u32)0xF0F0F0F0UL) >> 4) | ((__x & (u32)0x0F0F0F0FUL) << 4); \
59 __x = ((__x & (u32)0xCCCCCCCCUL) >> 2) | ((__x & (u32)0x33333333UL) << 2); \
60 __x = ((__x & (u32)0xAAAAAAAAUL) >> 1) | ((__x & (u32)0x55555555UL) << 1); \
61 __x; \
62})
63
64#define __constant_bitrev8(x) \
65({ \
66 u8 __x = x; \
67 __x = (__x >> 4) | (__x << 4); \
68 __x = ((__x & (u8)0xCCU) >> 2) | ((__x & (u8)0x33U) << 2); \
69 __x = ((__x & (u8)0xAAU) >> 1) | ((__x & (u8)0x55U) << 1); \
70 __x; \
71})
72
73#define bitrev32(x) \
74({ \
75 u32 __x = x; \
76 __builtin_constant_p(__x) ? \
77 __constant_bitrev32(__x) : \
78 __bitrev32(__x); \
79})
80
81#define bitrev16(x) \
82({ \
83 u16 __x = x; \
84 __builtin_constant_p(__x) ? \
85 __constant_bitrev16(__x) : \
86 __bitrev16(__x); \
87 })
88
89#define bitrev8x4(x) \
90({ \
91 u32 __x = x; \
92 __builtin_constant_p(__x) ? \
93 __constant_bitrev8x4(__x) : \
94 __bitrev8x4(__x); \
95 })
96
97#define bitrev8(x) \
98({ \
99 u8 __x = x; \
100 __builtin_constant_p(__x) ? \
101 __constant_bitrev8(__x) : \
102 __bitrev8(__x) ; \
103 })
104#endif /* _LINUX_BITREV_H */