bitrev.h

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/* SPDX-License-Identifier: GPL-2.0 */
#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
#include <asm-generic/bitops/__bitrev.h>
#define __bitrev32 generic___bitrev32
#define __bitrev16 generic___bitrev16
#define __bitrev8 generic___bitrev8
#endif /* CONFIG_HAVE_ARCH_BITREVERSE */
 
#define __bitrev8x4(x)  (__bitrev32(swab32(x)))
 
#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_bitrev8x4(x) \
({          \
    u32 ___x = x;   \
    ___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_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 bitrev8x4(x) \
({          \
    u32 __x = x;    \
    __builtin_constant_p(__x) ? \
    __constant_bitrev8x4(__x) :         \
    __bitrev8x4(__x);               \
 })
 
#define bitrev8(x) \
({          \
    u8 __x = x; \
    __builtin_constant_p(__x) ? \
    __constant_bitrev8(__x) :           \
    __bitrev8(__x)  ;           \
 })
#endif /* _LINUX_BITREV_H */