1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_ 3 #define _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_ 4 5 /* 6 * Compile time versions of __arch_hweightN() 7 */ 8 #define __const_hweight8(w) \ 9 ((unsigned int) \ 10 ((!!((w) & (1ULL << 0))) + \ 11 (!!((w) & (1ULL << 1))) + \ 12 (!!((w) & (1ULL << 2))) + \ 13 (!!((w) & (1ULL << 3))) + \ 14 (!!((w) & (1ULL << 4))) + \ 15 (!!((w) & (1ULL << 5))) + \ 16 (!!((w) & (1ULL << 6))) + \ 17 (!!((w) & (1ULL << 7))))) 18 19 #define __const_hweight16(w) (__const_hweight8(w) + __const_hweight8((w) >> 8 )) 20 #define __const_hweight32(w) (__const_hweight16(w) + __const_hweight16((w) >> 16)) 21 #define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32)) 22 23 /* 24 * Generic interface. 25 */ 26 #define hweight8(w) (__builtin_constant_p(w) ? __const_hweight8(w) : __arch_hweight8(w)) 27 #define hweight16(w) (__builtin_constant_p(w) ? __const_hweight16(w) : __arch_hweight16(w)) 28 #define hweight32(w) (__builtin_constant_p(w) ? __const_hweight32(w) : __arch_hweight32(w)) 29 #define hweight64(w) (__builtin_constant_p(w) ? __const_hweight64(w) : __arch_hweight64(w)) 30 31 /* 32 * Interface for known constant arguments 33 */ 34 #define HWEIGHT8(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight8(w)) 35 #define HWEIGHT16(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight16(w)) 36 #define HWEIGHT32(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight32(w)) 37 #define HWEIGHT64(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight64(w)) 38 39 /* 40 * Type invariant interface to the compile time constant hweight functions. 41 */ 42 #define HWEIGHT(w) HWEIGHT64((u64)w) 43 44 #endif /* _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_ */ 45
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