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Re: RFC: identifier GC


Tom Tromey wrote:

Richard> Can you measure the effect on compile-time and memory usage
Richard> of this change?  I guess building libstdc++ or something
Richard> similar (tramp3d..).

Definitely.

Right; I think this is key. The ugly nocopy bit in the C++ mangling code was -- at least at one point -- a relatively significant win. I think that if you look at the history, you'll find this was something we did in the process of speeding up the C++ front end. If this isn't measurable anymore, then we needn't care -- but if it is, maybe we should find a way to fold this into the main interface so that it's not an ugly on-the-side hack.


Richard> IMHO maintainability (and code readability) should have
Richard> preference over saving an extra pointer per tree identifier.

Ok. I don't really have a feeling for our memory use parameters.

I think this all depends on how much performance we get. If the ugliness is worth 1%, it's probably worth it; at 0.01% definitely not.


Thanks,

--
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713


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