From: MikkelFJ <mikkelfj-anti-spam@...>
Date: 2002-10-17T07:45:03+09:00
Subject: Re: Psyco


"Dave Thomas" <Dave@PragmaticProgrammer.com> wrote in message
news:m2vg42i7a9.fsf@zip.local.thomases.com...
> "MikkelFJ" <mikkelfj-anti-spam@bigfoot.com> writes:

> You
> might have to keep the old bytecodes lying around, and reactivate them
> if you ever determine any operators such as '+' had been changed.

True.
I actually believe this is the key to highperformance Ruby. There are many
ways you can optimize ruby. Most or all of these optimizations may become
invalidated, but rarely do. The solution is to always have a backup plan but
use the optimized version whereever possible.

For example a guarded compiled codesection that first tests for versioning
or involved classes. Or code compiled for special argument types like C++
template specialization.

Less aggressive is using dispatch tables that can be updated, but such that
bytecode - or assembler calls into the dispatch without hash lookups.
Calling methods not accounted for in the dispatch table goes via the
ordinary hash lookup.

Mikkel