1#include <math.h>
 2#include <stdint.h>
 3
 4int __fpclassify(double x)
 5{
 6	union {double f; uint64_t i;} u = {x};
 7	int e = u.i>>52 & 0x7ff;
 8	if (!e) return u.i<<1 ? FP_SUBNORMAL : FP_ZERO;
 9	if (e==0x7ff) return u.i<<12 ? FP_NAN : FP_INFINITE;
10	return FP_NORMAL;
11}