[squeak-dev] USe of isKindOf: is a crime against humanity
avalloud at smalltalk.comcastbiz.net
Sun Sep 1 06:35:05 UTC 2013
> It's slow - it scans up a class tree.
... my favorite part of the slowness is that isKindOf: causes an
unending sequence of megamorphic message sends which routinely need
expensive lookups or large, much more complicated caches than "simple"
PICs so the process is not overly slow. And of course, since the
isKindOf: code tends to be well refactored, there is effectively one
send site for every one of those megamorphic messages in the whole
image, which _ensures_ those send sites will be slow... ;).
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