expanded class
	EL_BIT_ROUTINES

inherit
	EL_BIT_ROUTINES_I

	EL_EXPANDED_ROUTINES

	EL_UNIX_IMPLEMENTATION

feature -- Measurement

	frozen leading_zeros_count_32 (n: NATURAL_32): INTEGER
		-- gcc Built-in Function: int ____builtin_clz (unsigned int x)
		-- Returns the number of leading 0-bits in x, starting at the most significant bit position.
		-- If x is 0, the result is undefined.
		external
			"C (unsigned int): EIF_INTEGER"
		alias
			"__builtin_clz"
		end

	frozen leading_zeros_count_64 (n: NATURAL_64): INTEGER
		-- gcc Built-in Function: int ____builtin_clzll (unsigned long long)
		-- Returns the number of leading 0-bits in x, starting at the most significant bit position.
		-- If x is 0, the result is undefined.
		external
			"C (unsigned long long): EIF_INTEGER"
		alias
			"__builtin_clzll"
		end

	frozen ones_count_32 (n: NATURAL_32): INTEGER
		-- gcc int __builtin_popcount (unsigned int x)
		-- Returns the number of 1-bits in x.
		external
			"C (unsigned int): EIF_INTEGER"
		alias
			"__builtin_popcount"
		end

	frozen ones_count_64 (n: NATURAL_64): INTEGER
		-- gcc int __builtin_popcountll (unsigned long long x)
		-- Returns the number of 1-bits in x.
		external
			"C (unsigned long long): EIF_INTEGER"
		alias
			"__builtin_popcountll"
		end

	frozen trailing_zeros_count_32 (n: NATURAL_32): INTEGER
		-- gcc Built-in Function: int __builtin_ctz (unsigned int x)
		-- Returns the number of trailing 0-bits in x, starting at the least significant bit position.
		-- If x is 0, the result is undefined.
		external
			"C (unsigned int): EIF_INTEGER"
		alias
			"__builtin_ctz"
		end

	frozen trailing_zeros_count_64 (n: NATURAL_64): INTEGER
		-- gcc Built-in Function: int __builtin_clzll (unsigned long long)
		-- Returns the number of trailing 0-bits in x, starting at the least significant bit position.
		-- If x is 0, the result is undefined.
		external
			"C (unsigned long long): EIF_INTEGER"
		alias
			"__builtin_ctzll"
		end
		
	frozen zero_or_one (n: NATURAL_32): NATURAL_32
		-- 1 if `n > 0' or else 0
		external
			"C inline"
		alias
			"[
				return (EIF_NATURAL_32)(unsigned int)$n >> (31 - __builtin_clz ((unsigned int)$n));
			]"
		end

end