Is there any special design decisions why qstr's are referenced by index in a table, instead of direct pointers? Having extra indirection of course affects performance, especially for cached archs.

My first thought was about limiting value domain, but "qstr" type is still defined as uint, so generally takes same size as a pointer. Though I found that qstr's are stored in parse nodes as MP_PARSE_NODE_LEAF_ARG(pn), which takes 4 bits for kind. But for pointer that would mean that qstr should be 16-byte aligned. Probably too harsh for strings in constrained environment indeed. But on the other hand, if this is only required for parsing source code...

So, I wonder is there're more tricks/optimizations which assume that qstr's have limited value domain, of that's the only one?