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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 arguments33 */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