[AutoBump] Merge with fixes of 4b3f251b (Oct 11) (12) (Needs torch bump) #449
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
jorickert
commented
Jan 13, 2025
•
jorickert
commented
- [AutoBump] Merge with fixes of edd1bbec (Oct 14, needs LLVM bump to Oct11) (82) torch-mlir#458
The concept of a 'program point' in the original data flow framework is ambiguous. It can refer to either an operation or a block itself. This representation has different interpretations in forward and backward data-flow analysis. In forward data-flow analysis, the program point of an operation represents the state after the operation, while in backward data flow analysis, it represents the state before the operation. When using forward or backward data-flow analysis, it is crucial to carefully handle this distinction to ensure correctness. This patch refactors the definition of program point, unifying the interpretation of program points in both forward and backward data-flow analysis. How to integrate this patch? For dense forward data-flow analysis and other analysis (except dense backward data-flow analysis), the program point corresponding to the original operation can be obtained by `getProgramPointAfter(op)`, and the program point corresponding to the original block can be obtained by `getProgramPointBefore(block)`. For dense backward data-flow analysis, the program point corresponding to the original operation can be obtained by `getProgramPointBefore(op)`, and the program point corresponding to the original block can be obtained by `getProgramPointAfter(block)`. NOTE: If you need to get the lattice of other data-flow analyses in dense backward data-flow analysis, you should still use the dense forward data-flow approach. For example, to get the Executable state of a block in dense backward data-flow analysis and add the dependency of the current operation, you should write: ``getOrCreateFor<Executable>(getProgramPointBefore(op), getProgramPointBefore(block))`` In case above, we use getProgramPointBefore(op) because the analysis we rely on is dense backward data-flow, and we use getProgramPointBefore(block) because the lattice we query is the result of a non-dense backward data flow computation. related dsscussion: https://discourse.llvm.org/t/rfc-unify-the-semantics-of-program-points/80671/8 corresponding PSA: https://discourse.llvm.org/t/psa-program-point-semantics-change/81479
jorickert
changed the title
mgehre-amd
approved these changes
Jan 14, 2025
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.