+# define _aligned_attribute(size) __attribute__((aligned(size)))
+# define likely(x) __builtin_expect(!!(x), 1)
+# define unlikely(x) __builtin_expect(!!(x), 0)
+# define inline inline __attribute__((always_inline))
+# define prefetch(x) __builtin_prefetch(x)
+# define is_constant(x) __builtin_constant_p(x)