+
+#ifndef UNLIKELY
+#if COMPILER(GCC)
+#define UNLIKELY(x) __builtin_expect((x), 0)
+#else
+#define UNLIKELY(x) (x)
+#endif
+#endif
+
+#ifndef LIKELY
+#if COMPILER(GCC)
+#define LIKELY(x) __builtin_expect((x), 1)
+#else
+#define LIKELY(x) (x)
+#endif
+#endif
+
+#ifndef NO_RETURN
+#if COMPILER(GCC)
+#define NO_RETURN __attribute((__noreturn__))
+#else
+#define NO_RETURN
+#endif
+#endif