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From: jeff@aiai.ed.ac.uk (Jeff Dalton)
Newsgroups: comp.lang.lisp
Subject: Re: Application of Smalltalk/Self compilation techniques to Common Lisp?
Keywords: cached compilation, invisible inlining, type customization, speed
Message-ID: <1567@skye.ed.ac.uk>
Date: 17 Jan 90 17:00:46 GMT
References: <12450@cbnewsc.ATT.COM>
Reply-To: jeff@aiai.UUCP (Jeff Dalton)
Organization: AIAI, University of Edinburgh, Scotland
Lines: 26

In article <12450@cbnewsc.ATT.COM> lgm@cbnewsc.ATT.COM (lawrence.g.mayka) writes:
   Have any commercial or research Lisp compilers attempted any of
   the optimization techniques published for Smalltalk and Self?  I'm
   thinking of techniques like the following:

   1) Use of bytecodes throughout the system to save space, but with
   on-the-fly, cached compilation of frequently called functions to
   improve execution speed.

I don't know of any.  Some Common Lisps always compile rather than
having an interpreter, and some use byte codes.  So I wouldn't be
surprised to find one that worked the way you suggest.  I do know of
one where you could explicitly say whether to compile to byte codes
or native code.

   2) Invisible function inlining.

   3) Type customization of compiled functions.  A single function
   may compile into more than one sequence of machine instructions:
   one version for the most common case and one version for the
   general case.

This is fairly common.  Most Common Lisps do it for the sequence
functions, for example.

-- Jeff