But overflow is a hardware issue - we run out of bits. The number range of a modulo operation on the other hand can be anything. That's why I said there are two

But overflow is a hardware issue - we run out of bits. The number range of a modulo operation on the other hand can be anything. That's why I said there are two issues that you seem to mix. Don't forget that overflow (running out of bits) is signaled by a flag for the CPU register where it's happening (accessible to a programmer only when using assembler). So I'm not sure what your plan really is here. To support modulo operations in hardware by using the limited bits of the registers limits your modulo operations to the size of the registers. If you are talking about purely software operations and not the hardware - I'm not sure - well, that exists. We already have modulo operations in all programming languages, it's not missing. And if you are talking about the hardware support, you are free to ignore the flags (which you only get to access in assembler anyway) and use the registers as a kind of "implied modulo", that's the point of the discussion that when overflow happens your code won't notice.