<regex>: Speed up skip optimization for default regex_traits in collate mode#5672
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StephanTLavavej merged 2 commits intomicrosoft:mainfrom Aug 16, 2025
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I'm mirroring this to the MSVC-internal repo - please notify me if any further changes are pushed. |
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In the default
std::regex_traits<char>andstd::regex_traits<wchar_t>implementation, thetranslate()function just returns its argument unchanged (see [re.traits]/4). This means that the call to this function can be skipped for these traits classes.This PR implements this change, and as a consequence, the skip optimization now engages the vectorized
std::searchimplementation incollatemode as well.The tests added by #5553 already check correct handling of
translate()in the skip optimization for user-provided regex traits, so this PR just adds a short variant of this test for defaultstd::regexandstd::wregex.Benchmark (only relevant lines):