[Vm-dev] #becomeUncompact not longer works in Cog/Stack VMs

Colin Putney colin at wiresong.com
Sat May 7 19:44:55 UTC 2011

On 2011-05-07, at 10:33 AM, Andreas Raab <andreas.raab at gmx.de> wrote:

> I don't recall if Eliot has published all the details (we went over it during some lunch break once) but the basic idea is described here:
> http://lists.squeakfoundation.org/pipermail/squeak-dev/2008-August/131167.html
> http://lists.squeakfoundation.org/pipermail/squeak-dev/2008-September/131206.html
> (of course, the compact class index is just an index into a class table)

Ok, I remember that now. I guess I was looking for a higher-level
description based on the whys and wherefores. It sounds like the
advantage here is space-saving, not speed: surely a class pointer is
faster to deal with than a multi-level table lookup. I guess it's
necessary because 64-bit pointers take a lot of space if you have one
for each object?


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