Re: Shrinking the C core

[Alfred M. Szmidt]

   Step one would be to identify why SBCL is so much faster.

The short reason why SBCL is faster is that SBCL uses lots of type
checking and interference, which allows it to figure out optimizations
better.  And then using assembly to implement such optimizations.  CL
code compiled without DECLARE/DECLAIM is generally slow, but can be
made fast if you are very careful, and lucky that the things you need
are implemented as VOPs -- which are entierly unportable.

It also has the luxury of using a language that is set more or less in
stone, that doesn't change constantly.  Which means the developers can
spend quite a bit more time on optimizing what they have.

   If that fails maybe one would consider ECL or some other
   faster, yet portable solution ...

"Porting" Emacs to CL is not just slap ECL or some CL implementation
on top.  Adding type checking of the sort that SBCL does, would be
possible but ALOT of work.  It would most definitly require a entierly
new VM, and with that comes dragons.