| #include <math.h> | |
| #include <stdint.h> | |
| double frexp(double x, int *e) | |
| { | |
| union { double d; uint64_t i; } y = { x }; | |
| int ee = y.i>>52 & 0x7ff; | |
| if (!ee) { | |
| if (x) { | |
| x = frexp(x*0x1p64, e); | |
| *e -= 64; | |
| } else *e = 0; | |
| return x; | |
| } else if (ee == 0x7ff) { | |
| return x; | |
| } | |
| *e = ee - 0x3fe; | |
| y.i &= 0x800fffffffffffffull; | |
| y.i |= 0x3fe0000000000000ull; | |
| return y.d; | |
| } |