| #include <math.h> | |
| #include <stdint.h> | |
| int __fpclassify(double x) { | |
| union { | |
| double f; | |
| uint64_t i; | |
| } u = {x}; | |
| int e = u.i >> 52 & 0x7ff; | |
| if (!e) | |
| return u.i << 1 ? FP_SUBNORMAL : FP_ZERO; | |
| if (e == 0x7ff) | |
| return u.i << 12 ? FP_NAN : FP_INFINITE; | |
| return FP_NORMAL; | |
| } |