+#define isunordered(x,y) (isnan((x)) ? ((y),1) : isnan((y)))
+
+static inline int __isrel(long double __x, long double __y, int __rel)
+{
+ if (isunordered(__x, __y)) return 0;
+ if (__rel==-2) return __x < __y;
+ if (__rel==2) return __x > __y;
+ if (__rel==-1) return __x <= __y;
+ if (__rel==1) return __x >= __y;
+ return __x != __y;
+}
+
+#define isless(x,y) __isrel((x), (y), -2)
+#define islessequal(x,y) __isrel((x), (y), -1)
+#define islessgreater(x,y) __isrel((x), (y), 0)
+#define isgreaterequal(x,y) __isrel((x), (y), 1)
+#define isgreater(x,y) __isrel((x), (y), 2)
+