[regexp] Faster case closure computation - #505
Merged
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Summary
Computing the case closure of a set of code points is currently extremely slow since we compute the case closure for each code point in that set, which may be very large (e.g. consider
\D). We can speed this up by only computing the case closure for the subset of code points that actually has a case closure containing any other code points, which only applies to a much smaller set of code points than the full range. Precompute this set (for both unicode and non-unicode modes) at build time, then use it for more efficient case closure construction. The same technique can be done inMaybeSimpleCaseFoldingin case insensitive unicode sets mode.Provides a significant speedup anywhere case insensitive mode is used with large code point sets. For example
"regression/000026.js"which is executing just a handful of RegExps speeds up from to 0.861 to 0.006 seconds.Tests