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Re: [Patch] Batch of basic_string correctness and performance work


Paolo Carlini wrote:

Gawain Bolton wrote:

Yes this is exactly the type of code I'm against inlining. It contains 2 tests which will never benefit from branch prediction, which for modern CPUs is a major handicap.


Frankly, Gawain, I don't like too much your stance.

My stance? Oh you mean the constructive criticism I'm trying to give you? Well how silly of me to think that I could give feedback for the proposed the changes on the receiver list for this open source project.


If you don't consider candidates for inlining functions like the current push_back (which must be executed once for each char and is definitely performance critical) then probably you disagree also with the basic design principle of basic_streambuf. Empirically, all my tests provide evidence in favor of that, not only on x86, even more on "saner" architectures like x86_64. Since it looks like you have very clear ideas about the way to go, please test thoroughly my inline -> out-of-line patch of yesterday, and we'll trust you when you will report the outcome of your results.

Yes, given how receptive you are I'm sure you'll give any "results" I present the utmost consideration.



On many points your message is misleading, doesn't take into account history, past empirical evidence, and so on, sorry I don't find very productive replying to each one.

Oh I quite understand. In future, I suggest you just commit any changes you propose. I'm sure they'll always be beyond any possible cricticism.





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