[deliverable/linux.git] / include / asm-generic / bitops / const_hweight.h

#ifndef _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_
#define _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_

/*
 * Compile time versions of __arch_hweightN()
 */
#define __const_hweight8(w)		\
	((unsigned int)			\
	 ((!!((w) & (1ULL << 0))) +	\
	  (!!((w) & (1ULL << 1))) +	\
	  (!!((w) & (1ULL << 2))) +	\
	  (!!((w) & (1ULL << 3))) +	\
	  (!!((w) & (1ULL << 4))) +	\
	  (!!((w) & (1ULL << 5))) +	\
	  (!!((w) & (1ULL << 6))) +	\
	  (!!((w) & (1ULL << 7)))))

#define __const_hweight16(w) (__const_hweight8(w)  + __const_hweight8((w)  >> 8 ))
#define __const_hweight32(w) (__const_hweight16(w) + __const_hweight16((w) >> 16))
#define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32))

/*
 * Generic interface.
 */
#define hweight8(w)  (__builtin_constant_p(w) ? __const_hweight8(w)  : __arch_hweight8(w))
#define hweight16(w) (__builtin_constant_p(w) ? __const_hweight16(w) : __arch_hweight16(w))
#define hweight32(w) (__builtin_constant_p(w) ? __const_hweight32(w) : __arch_hweight32(w))
#define hweight64(w) (__builtin_constant_p(w) ? __const_hweight64(w) : __arch_hweight64(w))

/*
 * Interface for known constant arguments
 */
#define HWEIGHT8(w)  (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight8(w))
#define HWEIGHT16(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight16(w))
#define HWEIGHT32(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight32(w))
#define HWEIGHT64(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight64(w))

/*
 * Type invariant interface to the compile time constant hweight functions.
 */
#define HWEIGHT(w)   HWEIGHT64((u64)w)

#endif /* _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_ */
Commit	Line	Data
1527bc8b PZ	1	#ifndef _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_
	2	#define _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_
	3
	4	/*
	5	* Compile time versions of __arch_hweightN()
	6	*/
	7	#define __const_hweight8(w) \
c32fa99f PW	8	((unsigned int) \
	9	((!!((w) & (1ULL << 0))) + \
	10	(!!((w) & (1ULL << 1))) + \
	11	(!!((w) & (1ULL << 2))) + \
	12	(!!((w) & (1ULL << 3))) + \
	13	(!!((w) & (1ULL << 4))) + \
	14	(!!((w) & (1ULL << 5))) + \
	15	(!!((w) & (1ULL << 6))) + \
	16	(!!((w) & (1ULL << 7)))))
1527bc8b PZ	17
	18	#define __const_hweight16(w) (__const_hweight8(w) + __const_hweight8((w) >> 8 ))
	19	#define __const_hweight32(w) (__const_hweight16(w) + __const_hweight16((w) >> 16))
	20	#define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32))
	21
	22	/*
	23	* Generic interface.
	24	*/
	25	#define hweight8(w) (__builtin_constant_p(w) ? __const_hweight8(w) : __arch_hweight8(w))
	26	#define hweight16(w) (__builtin_constant_p(w) ? __const_hweight16(w) : __arch_hweight16(w))
	27	#define hweight32(w) (__builtin_constant_p(w) ? __const_hweight32(w) : __arch_hweight32(w))
	28	#define hweight64(w) (__builtin_constant_p(w) ? __const_hweight64(w) : __arch_hweight64(w))
	29
	30	/*
	31	* Interface for known constant arguments
	32	*/
	33	#define HWEIGHT8(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight8(w))
	34	#define HWEIGHT16(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight16(w))
	35	#define HWEIGHT32(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight32(w))
	36	#define HWEIGHT64(w) (BUILD_BUG_ON_ZERO(!__builtin_constant_p(w)) + __const_hweight64(w))
	37
	38	/*
	39	* Type invariant interface to the compile time constant hweight functions.
	40	*/
	41	#define HWEIGHT(w) HWEIGHT64((u64)w)
	42
	43	#endif /* _ASM_GENERIC_BITOPS_CONST_HWEIGHT_H_ */