msb
Calculates the most significant bit position.
Arguments
whole- The value to analyze (0 to 2^64)
Returns
A tuple of (bit_position, power_of_2) where:
bit_positionis the index of the MSB (0-64)power_of_2is 2^bit_position
Fully qualified path: cairo_fp::f128::math::lut::msb
fn msb(whole: u128) -> (u128, u128)