Here are several papers that should be helpful:

Jan Vitek, ``Compact Dispatch Tables for Dynamically Typed Programming
Languages,'' Object Applications, D. Tsichritzis (Ed.), Centre
Universitaire d'Informatique, University of Geneva, August 1996, pp.
81-138.
Jan Vitek and R. Nigel Horspool, ``Compacting Dispatch Tables for
Dynamically Typed Object Oriented Languages,'' Proceedings of Compiler
Construction, CC'96, Springer-Verlag, 1996.
Karel Driesen, Urs Hoelzle and Jan Vitek, ``Message Dispatch on
Pipelined Processors,'' Proceedings of the European Conference on Object
Oriented Programming, ECOOP'95, 1995. File:
http://cuiwww.unige.ch/OSG/people/jvitek/Publications/ecoop95.ps.gz 
Jan Vitek and R. Nigel Horspool, ``Taming Message Passing: Efficient
method lookup for dynamically typed object-oriented languages,''
Proceedings of the European Conference on Object Oriented Programming,
ECOOP'94, Springer-Verlag, Bologna, Italy, 1994.

These are available from http://cuiwww.unige.ch/osgrefs?osg-ftp

-- Dwight

Hernan Wilkinson wrote:
> 
> Hi everybody,
>     I'm writing my master's thesis and I would like some advise from you.
> (This mail may be a little bit long)
> 
>     I've been reading some papers on how to make Smalltalk and Self run
> faster. I have an idea on how to make the Smalltalk message lookup faster,
> but before doing anything, I would like to have some feedback from you. I'll
> try to write a short description of my idea.
[....................]
>     Anyway, any lead to information, paper or research done about this would
> be a great help.
>     Any comment (good or bad) will be appreciated also.
> 
>     Thank you,
>     Hernan.
> 
> PS: I know that making the message look up faster will not affect directly
> the performance of the VM.
> 
> _____________________________________________
> Hernán A. Wilkinson
> BitX S.A. Argentina
> Phone: (54-11) 4574-1544  Fax: (54-11)4573-3368
> Franco 3419 . 1er piso - (1419)- Buenos Aires - Argentina
> Web: www.bitx.com.ar