| 1 | #include <math.h> |
| 2 | #include <stdint.h> |
| 3 | |
| 4 | int __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 | } |