Return the floor log base 2 of the specified value, -1 if the value is zero. (64 bit edition.)
Declared in <llvm/Support/MathExtras.h>
unsigned int
Log2_64(uint64_t Value);The floor log base 2 of Value, or -1 if Value is zero.
| Name | Description |
|---|---|
| Value | 64-bit value whose floor log2 is returned. |