Make join and related operations for Unions preserve equal arguments
#1104
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
Issue #1091 was caused by the join/widen (and corresponding smart operations) for unions in ValueDomain not return the same element. The optimization in PMap that returns the unchanged map when two physically identical maps were joined was thus yielding a different value in the from-scratch run compared to the incremental run.
michael-schwarz
approved these changes
Jul 11, 2023
sim642
approved these changes
Jul 18, 2023
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Outdated suggestions cannot be applied.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.
The implementation of
MapTop.joinuses a short-circuit optimization that relies on the fact thatjoin x x = xanalyzer/src/domains/mapDomain.ml
Lines 439 to 442 in 3af00a8
Issue #1091 was caused by the$(field: \bot, value: \bot)$ yielded $(field: \bot, value: \bot)$ . In the incremental run, the physical equality of the maps containing the Union abstraction was no longer given, and the result of the join is $(field: \bot, value: \top)$ .
joinoperation for unions inValueDomainnot satisfying thejoin x x = xproperty.In the from-scratch run, when physical equality was given, the
joinof two abstract unions of the formTherefore, this PR changes the behavior of the
joinandwidenoperations for theUnionDomain, such thatjoin x x = xandwiden x x = xis ensured.Fixes #1091.