refactor(ancestors): replace with bit set #940
Draft
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
…ill be plenty also fix an iterator bug this revealed
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Outdated suggestions cannot be applied.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 change was originally motivated by a segfault we were seeing in replay. The stack trace pointed to the line of code that dereferences ancestors in freezeSlot. Turned out, ancestors wasn't related to the problem in any way and the stack trace was total nonsense. Anyway, we can still merge the improvement to ancestors.
Ancestors is a hashmap which requires memory allocations and makes you pass things around by pointer, which leads to mistakes. This is overkill. It can just be a bit set tracking some recent slots. No allocations are needed.
This switches the implementation to be a bit set.