method dictionary lookups and walking up the inheritance tree

Michael Haupt mhaupt at gmail.com
Tue May 16 18:54:03 UTC 2006


Hi Andreas,

On 5/16/06, Andreas Raab <andreas.raab at gmx.de> wrote:
> Your observation is incorrect. The superclass' method dictionary will
> not be copied. What you see in ClassBuilder is that the method
> dictionary of an "old version" of the class is being copied. This is
> necessary to support class migration, e.g., adding and removing
> variables in a class or one of its superclasses.

indeed; Tim Rowledge has pointed this out on the Squeak-dev list
already. Next time I'll look a little closer. :-)

So, the only optimisation that is performed for method lookups is the
method cache in the Interpreter, right? Is it correct that its size is
initialised to 512 entries (I'm not sure; I found that in
InterpreterSimulator)?

Are there other optimisations that one could implement, e.g., as a
first step in Squeak VM hacking? Not that I had myself in mind... ;-)

Best,

Michael



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