[libcxx-commits] [libcxx] [libc++] Optimize `text_encoding::environment_is()` for UTF-8, ASCII, Windows1252 and ISOLatin1 (PR #225136)

[William Tran-Viet via libcxx-commits]

smallp-o-p wrote:

> > > I'd really like to see some numbers on this. I can't reproduce that the user has to store any table at all with the current implementation: https://godbolt.org/z/7hjTMr9fP
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> > > I'm also not sure why we care too much about the performance here? Is this function expected to be hot in any way?
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> > 
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> > The best I could do is show the aliases in `strings`: https://godbolt.org/z/GsvnKMj94, I'm not entirely sure why other tools can't find it.
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> 
> Because it's in the debug info: https://godbolt.org/z/4Tf366hPP
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> > "Optimization" in this case is with respect to disk space and memory.
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> Yeah, I'm not convinced this is worth the minuscule improvements we seem to get here.

The compiler is far smarter than I gave it credit for, so I'll close this patch since it appears the original concern was moot from the beginning.

https://github.com/llvm/llvm-project/pull/225136