Function disjoint_bitor 

pub const unsafe fn disjoint_bitor<T>(a: T, b: T) -> T
where
    T: DisjointBitOr,

🔬This is a nightly-only experimental API. (core_intrinsics)

Combine two values which have no bits in common.

This allows the backend to implement it as a + b or a | b, depending which is easier to implement on a specific target.

Safety

Requires that (a & b) == 0, or equivalently that (a | b) == (a + b).

Otherwise it’s immediate UB.