🚀 go-pugleaf

RetroBBS NetNews Server

Inspired by RockSolid Light RIP Retro Guy

Article View: comp.lang.prolog
Article #1194

value trailing (was Arrays in Prolog)

#1194
From: Andrew Taylor
Date: Fri, 14 Sep 1990 01:16
19 lines
1684 bytes
In article <1032@ecrc.de> micha@ecrc.de (Micha Meier) writes:
>This is interesting. Is no-one out there using the trail to store
>directly the old value together with its address? This is the
>so-called value-trailing, as opposed to the usual address trailing

I'm experimenting with a scheme where bound variables never need dereferencing.
This is done by keeping sharing variables in a circular list and when
binding a variable binding each variable in the list. This needs value-trailing.

The hope is this scheme works better than the usual reference chain scheme
where global analysis is involved.  It should produce faster analysis
and better results where analysis becomes imprecise, where a module is
analysed alone and where information from mode declarations.

I'm not worried about doubling the trail size. Global analysis removes
most trailing anyway. I think the cost of the extra trail read & writes is
probably less than the benefits.

Andrew
Technical Details
Message-ID: <1198@cluster.cs.su.oz.au>
Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!munnari.oz.au!metro!cluster!andrewt
References: <90239.175243SCHMIED@DB0TUI11.BITNET> <3899@bingvaxu.cc.binghamton.edu> <1990Aug28.065353.13951@sics.se> <3904@bingvaxu.cc.binghamton.edu> <1990Aug29.095308.18522@sics.se> <3907@bingvaxu.cc.binghamton.edu> <1032@ecrc.de>

Show Full Headers
Complete Article Headers
Path: arc1-ca.pugleaf.net!utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!munnari.oz.au!metro!cluster!andrewt
From: andrewt@cs.su.oz (Andrew Taylor)
Newsgroups: comp.lang.prolog
Subject: value trailing (was Arrays in Prolog)
Message-ID: <1198@cluster.cs.su.oz.au>
Date: 14 Sep 90 01:16:55 GMT
References: <90239.175243SCHMIED@DB0TUI11.BITNET> <3899@bingvaxu.cc.binghamton.edu> <1990Aug28.065353.13951@sics.se> <3904@bingvaxu.cc.binghamton.edu> <1990Aug29.095308.18522@sics.se> <3907@bingvaxu.cc.binghamton.edu> <1032@ecrc.de>
Sender: news@cluster.cs.su.oz.au
Reply-To: andrewt@cluster.cs.su.oz (Andrew Taylor)
Organization: Basser Dept of Computer Science, University of Sydney, Australia
Lines: 19