compile: add fast path for c_char #658
Merged
Conversation
This file contains 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
This fixes a pretty bad performance bug in the NFA compiler. In particular, c_char was implemented by diverting to c_class, which is correct, but rather costly to do for every single character in a regex. This causes way more things than necessary to go through the class compilation infrastructure, which includes the suffix caching. We fix this by just special casing c_char. This speeds up regex compilation in #657 by around 30%. Fixes #657
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
This fixes a pretty bad performance bug in the NFA compiler. In
particular, c_char was implemented by diverting to c_class, which is
correct, but rather costly to do for every single character in a regex.
This causes way more things than necessary to go through the class
compilation infrastructure, which includes the suffix caching.
We fix this by just special casing c_char. This speeds up regex
compilation in #657 by around 30%.
Fixes #657