Optimization of the main DFA loop: avoid unnecessary in-loop runtime checks for matching DFA states #455
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…op runtime checks for matching DFA states 1) Avoid adjusting `lastmatch` in-loop. Instead, adjust it once before returning from the `InlinedSearchLoop<>` 2) Avoid run-time checks before saving `match_id`-s; instead, create additional template specializations for `InlinedSearchLoop<>` and only do that when necessary. RE2::Set is a very special use-case of re2 (and let's be honest, a rarely used one). Yet, those in-loop runtime checks impose a performance penalty on all other use-cases.
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lastmatchin-loop. Instead, adjust it once before returning from theInlinedSearchLoop<>2) Avoid run-time checks before saving match IDs inmatches; instead, create additional template specializations forInlinedSearchLoop<>and only do that when necessary. RE2::Set is a very special use-case of re2 (and let's be honest, a rarely used one). Yet, those in-loop runtime checks impose a performance penalty on all other use-cases.