Function atomic_i_sub

pub unsafe fn atomic_i_sub<I: Integer, const SCOPE: u32, const SEMANTICS: u32>(
    ptr: &mut I,
    value: I,
) -> I

Perform the following steps atomically with respect to any other atomic accesses within SCOPE to the same location:

1. load through ptr to get an original value,
2. get a new value by integer subtraction of original value and value, and
3. store the new value back through ptr.

The result is the Original Value.