Naively, yes. In practice, you could treat them exactly the same and either decrement the physical pointer by 1 unit (so an index of 0 would underflow) or leave

Naively, yes. In practice, you could treat them exactly the same and either decrement the physical pointer by 1 unit (so an index of 0 would underflow) or leave the first index unused or for metadata (eg. array length) There might be some other tricks you can play depending on your instruction set, but nothing comes to mind.