Re: Ideal performance of ELisp

[Stefan Monnier]

Mattias Engdegård [2022-08-17 16:19:08] wrote:
> 17 aug. 2022 kl. 16.04 skrev Stefan Monnier <monnier@iro.umontreal.ca>:
>> IIRC the limitation is only in the size of relative jumps, so we might
>> be able to fix it just by adding a new "longbranch" instruction,
> All bytecode jumps are 16-bit absolute.

Oh well.

> It is something we would like to change; relative jumps would make the
> interpreter faster.

Sounds like it would break backward compatibility, tho :-(
We can increase the range fairly easily if 16bit is not enough, tho.
E.g. we can just use the destination 65535 as a flag to indicate that
the next 4 bytes contain a 32bit destination.


        Stefan