gh-153568: Cache repeated identifiers while parsing#153577
Open
pablogsal wants to merge 1 commit into
Open
Conversation
Identifiers repeat constantly in real code, so the parser now reuses the interned name created the first time it sees a given spelling.
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Every occurrence of a name paid a UTF-8 decode, a hash and an intern lookup, even though identifiers repeat constantly in real code. A small per-parse table now reuses the interned name created the first time a given spelling is seen, and everything it stores lives in the parse arena so no lifetime management is needed.
Benchmark (parsing 8 of the largest stdlib files, 1.3 MB, 20 times per run with
_PyParser_ASTFromString— parser only, no AST-to-Python conversion; pyperf, interleaved runs):