They don't support general arithmetic. They do have member functions for abs, multiplication, negation and power operations, but they are all checked/saturating if they can result in 0.

If you want to do actual arithmetic, you have to get the internal i16, perform the arithmetic, then rewrap it.

https://godbolt.org/z/T5e36zzM5

Whether we can efficiently do other arithmetic depends on what we're doing, but that's not necessarily on our critical path even if the division is.