[libcxx-commits] [PATCH] D155820: [libc++] Optimize internal function in <system_error>

[Louis Dionne via Phabricator via libcxx-commits]

ldionne added inline comments.


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Comment at: libcxx/src/system_error.cpp:53
     return default_error_condition(code) == condition;
 }
 
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Just to put things in perspective, `system_error` is an exception type. I don't think we should pursue changes just for the sake of optimizing the construction of exception types.

However, mixed with https://github.com/llvm/llvm-project/issues/63985, I think this change could be worthwhile since we would both make this faster (ok, whatever) but also remove an unused function from our ABI surface (which is nice).

So personally I think the approach we should take here is to remove `__init` from our ABI and replace it with a function that is internal to `system_error.cpp` like you did here. Removing `__init` from the ABI will require a bit of preparation work to make sure it's safe but that's something we can help with if you update this patch with the full changes.

Just to set expectations, I would target this for LLVM 18, not LLVM 17.


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  https://reviews.llvm.org/D155820/new/

https://reviews.llvm.org/D155820