Improve expression propagation by removing redundant Phi functions #382
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
|
I've actually noticed that we already have a class to cleanup redundant Phi functions. ( |
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Outdated suggestions cannot be applied.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.
In some cases the decompiler fails to reconstruct simple control structures, because the decompiled code contains redundant variables. These variables are caused by Phi functions, that use the same value indifferent to the control flow path taken.
This PR adds code that removes these redundant Phi functions before each expression propagation iteration, enabling more expressions to be propagated.
An example where this causes a switch to not be constructed is
test17in systemtest/32/3/test_condition.