#ifndef _LINUX_BITREV_H #define _LINUX_BITREV_H #include <linux/types.h> #ifdef CONFIG_HAVE_ARCH_BITREVERSE #include <asm/bitrev.h> #define __bitrev32 __arch_bitrev32 #define __bitrev16 __arch_bitrev16 #define __bitrev8 __arch_bitrev8 #else extern u8 const byte_rev_table[256]; static inline u8 __bitrev8(u8 byte) { return byte_rev_table[byte]; } static inline u16 __bitrev16(u16 x) { return (__bitrev8(x & 0xff) << 8) | __bitrev8(x >> 8); } static inline u32 __bitrev32(u32 x) { return (__bitrev16(x & 0xffff) << 16) | __bitrev16(x >> 16); } #endif /* CONFIG_HAVE_ARCH_BITREVERSE */ #define __constant_bitrev32(x) \ ({ \ u32 __x = x; \ __x = (__x >> 16) | (__x << 16); \ __x = ((__x & (u32)0xFF00FF00UL) >> 8) | ((__x & (u32)0x00FF00FFUL) << 8); \ __x = ((__x & (u32)0xF0F0F0F0UL) >> 4) | ((__x & (u32)0x0F0F0F0FUL) << 4); \ __x = ((__x & (u32)0xCCCCCCCCUL) >> 2) | ((__x & (u32)0x33333333UL) << 2); \ __x = ((__x & (u32)0xAAAAAAAAUL) >> 1) | ((__x & (u32)0x55555555UL) << 1); \ __x; \ }) #define __constant_bitrev16(x) \ ({ \ u16 __x = x; \ __x = (__x >> 8) | (__x << 8); \ __x = ((__x & (u16)0xF0F0U) >> 4) | ((__x & (u16)0x0F0FU) << 4); \ __x = ((__x & (u16)0xCCCCU) >> 2) | ((__x & (u16)0x3333U) << 2); \ __x = ((__x & (u16)0xAAAAU) >> 1) | ((__x & (u16)0x5555U) << 1); \ __x; \ }) #define __constant_bitrev8(x) \ ({ \ u8 __x = x; \ __x = (__x >> 4) | (__x << 4); \ __x = ((__x & (u8)0xCCU) >> 2) | ((__x & (u8)0x33U) << 2); \ __x = ((__x & (u8)0xAAU) >> 1) | ((__x & (u8)0x55U) << 1); \ __x; \ }) #define bitrev32(x) \ ({ \ u32 __x = x; \ __builtin_constant_p(__x) ? \ __constant_bitrev32(__x) : \ __bitrev32(__x); \ }) #define bitrev16(x) \ ({ \ u16 __x = x; \ __builtin_constant_p(__x) ? \ __constant_bitrev16(__x) : \ __bitrev16(__x); \ }) #define bitrev8(x) \ ({ \ u8 __x = x; \ __builtin_constant_p(__x) ? \ __constant_bitrev8(__x) : \ __bitrev8(__x) ; \ }) #endif /* _LINUX_BITREV_H */