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2025-10-28 [MLIR] Revamp RegionBranchOpInterface (#165429)Mehdi Amini
This is still somehow a WIP, we have some issues with this interface that are not trivial to solve. This patch tries to make the concepts of RegionBranchPoint and RegionSuccessor more robust and aligned with their definition: - A `RegionBranchPoint` is either the parent (`RegionBranchOpInterface`) op or a `RegionBranchTerminatorOpInterface` operation in a nested region. - A `RegionSuccessor` is either one of the nested region or the parent `RegionBranchOpInterface` Some new methods with reasonnable default implementation are added to help resolving the flow of values across the RegionBranchOpInterface. It is still not trivial in the current state to walk the def-use chain backward with this interface. For example when you have the 3rd block argument in the entry block of a for-loop, finding the matching operands requires to know about the hidden loop iterator block argument and where the iterargs start. The API is designed around forward-tracking of the chain unfortunately. Try to reland #161575 ; I suspect a buildbot incremental build issue.
2025-10-28Revert " [MLIR] Revamp RegionBranchOpInterface " (#165356)Mehdi Amini
Reverts llvm/llvm-project#161575 Broke Windows on ARM buildbot build, needs investigations.
2025-10-28 [MLIR] Revamp RegionBranchOpInterface (#161575)Mehdi Amini
This is still somehow a WIP, we have some issues with this interface that are not trivial to solve. This patch tries to make the concepts of RegionBranchPoint and RegionSuccessor more robust and aligned with their definition: - A `RegionBranchPoint` is either the parent (`RegionBranchOpInterface`) op or a `RegionBranchTerminatorOpInterface` operation in a nested region. - A `RegionSuccessor` is either one of the nested region or the parent `RegionBranchOpInterface` Some new methods with reasonnable default implementation are added to help resolving the flow of values across the RegionBranchOpInterface. It is still not trivial in the current state to walk the def-use chain backward with this interface. For example when you have the 3rd block argument in the entry block of a for-loop, finding the matching operands requires to know about the hidden loop iterator block argument and where the iterargs start. The API is designed around forward-tracking of the chain unfortunately.
2025-08-15[mlir][SCF] `scf.for`: Add support for unsigned integer comparison (#153379)Matthias Springer
Add a new unit attribute to allow for unsigned integer comparison. Example: ```mlir scf.for unsigned %iv_32 = %lb_32 to %ub_32 step %step_32 : i32 { // body } ``` Discussion: https://discourse.llvm.org/t/scf-should-scf-for-support-unsigned-comparison/84655
2025-07-24[mlir][NFC] update `mlir/Dialect` create APIs (20/n) (#149927)Maksim Levental
See https://github.com/llvm/llvm-project/pull/147168 for more info.
2024-12-20[mlir] Enable decoupling two kinds of greedy behavior. (#104649)Jacques Pienaar
The greedy rewriter is used in many different flows and it has a lot of convenience (work list management, debugging actions, tracing, etc). But it combines two kinds of greedy behavior 1) how ops are matched, 2) folding wherever it can. These are independent forms of greedy and leads to inefficiency. E.g., cases where one need to create different phases in lowering and is required to applying patterns in specific order split across different passes. Using the driver one ends up needlessly retrying folding/having multiple rounds of folding attempts, where one final run would have sufficed. Of course folks can locally avoid this behavior by just building their own, but this is also a common requested feature that folks keep on working around locally in suboptimal ways. For downstream users, there should be no behavioral change. Updating from the deprecated should just be a find and replace (e.g., `find ./ -type f -exec sed -i 's|applyPatternsAndFoldGreedily|applyPatternsGreedily|g' {} \;` variety) as the API arguments hasn't changed between the two.
2024-01-25[mlir][IR] Add rewriter API for moving operations (#78988)Matthias Springer
The pattern rewriter documentation states that "*all* IR mutations [...] are required to be performed via the `PatternRewriter`." This commit adds two functions that were missing from the rewriter API: `moveOpBefore` and `moveOpAfter`. After an operation was moved, the `notifyOperationInserted` callback is triggered. This allows listeners such as the greedy pattern rewrite driver to react to IR changes. This commit narrows the discrepancy between the kind of IR modification that can be performed and the kind of IR modifications that can be listened to.
2024-01-17[mlir][IR] Rename "update root" to "modify op" in rewriter API (#78260)Matthias Springer
This commit renames 4 pattern rewriter API functions: * `updateRootInPlace` -> `modifyOpInPlace` * `startRootUpdate` -> `startOpModification` * `finalizeRootUpdate` -> `finalizeOpModification` * `cancelRootUpdate` -> `cancelOpModification` The term "root" is a misnomer. The root is the op that a rewrite pattern matches against (https://mlir.llvm.org/docs/PatternRewriter/#root-operation-name-optional). A rewriter must be notified of all in-place op modifications, not just in-place modifications of the root (https://mlir.llvm.org/docs/PatternRewriter/#pattern-rewriter). The old function names were confusing and have contributed to various broken rewrite patterns. Note: The new function names use the term "modify" instead of "update" for consistency with the `RewriterBase::Listener` terminology (`notifyOperationModified`).
2023-08-14[mlir][SCF][NFC] Add helper functions to get body of scf.whileMatthias Springer
Add two new helper functions `getBeforeBody` and `getAfterBody` to be consistent with "scf.for" (`getBody`) and to show in the API that both regions have exactly one block. Also simplify some code that assumed that there can be more than one block in a region. Differential Revision: https://reviews.llvm.org/D157860
2023-02-27[mlir][SCF] Fix incorrect API usage in RewritePatternsMatthias Springer
Incorrect API usage was detected by D144552. Differential Revision: https://reviews.llvm.org/D144636
2022-09-29[mlir][arith] Change dialect name from Arithmetic to ArithJakub Kuderski
Suggested by @lattner in https://discourse.llvm.org/t/rfc-define-precise-arith-semantics/65507/22. Tested with: `ninja check-mlir check-mlir-integration check-mlir-mlir-spirv-cpu-runner check-mlir-mlir-vulkan-runner check-mlir-examples` and `bazel build --config=generic_clang @llvm-project//mlir:all`. Reviewed By: lattner, Mogball, rriddle, jpienaar, mehdi_amini Differential Revision: https://reviews.llvm.org/D134762
2022-08-31[MLIR] Update pass declarations to new autogenerated filesMichele Scuttari
The patch introduces the required changes to update the pass declarations and definitions to use the new autogenerated files and allow dropping the old infrastructure. Reviewed By: mehdi_amini, rriddle Differential Review: https://reviews.llvm.org/D132838
2022-08-30Revert "[MLIR] Update pass declarations to new autogenerated files"Michele Scuttari
This reverts commit 2be8af8f0e0780901213b6fd3013a5268ddc3359.
2022-08-30[MLIR] Update pass declarations to new autogenerated filesMichele Scuttari
The patch introduces the required changes to update the pass declarations and definitions to use the new autogenerated files and allow dropping the old infrastructure. Reviewed By: mehdi_amini, rriddle Differential Review: https://reviews.llvm.org/D132838
2022-06-26[mlir] Generalize SCF passes to not have to run on FuncOp.Stella Laurenzo
Seems to have been an accident of history and none of these had any reason to be restricted to FuncOp. Differential Revision: https://reviews.llvm.org/D128614
2022-06-20[mlir] move SCF headers to SCF/{IR,Transforms} respectivelyAlex Zinenko
This aligns the SCF dialect file layout with the majority of the dialects. Reviewed By: jpienaar Differential Revision: https://reviews.llvm.org/D128049
2022-04-18[mlir:NFC] Remove the forward declaration of FuncOp in the mlir namespaceRiver Riddle
FuncOp has been moved to the `func` namespace for a little over a month, the using directive can be dropped now.
2022-03-01[mlir] Trim a huge number of unnecessary dependencies on the Func dialectRiver Riddle
The Func has a large number of legacy dependencies carried over from the old Standard dialect, which was pervasive and contained a large number of varied operations. With the split of the standard dialect and its demise, a lot of lingering dead dependencies have survived to the Func dialect. This commit removes a large majority of then, greatly reducing the dependence surface area of the Func dialect.
2022-03-01[mlir] Rename the Standard dialect to the Func dialectRiver Riddle
The last remaining operations in the standard dialect all revolve around FuncOp/function related constructs. This patch simply handles the initial renaming (which by itself is already huge), but there are a large number of cleanups unlocked/necessary afterwards: * Removing a bunch of unnecessary dependencies on Func * Cleaning up the From/ToStandard conversion passes * Preparing for the move of FuncOp to the Func dialect See the discussion at https://discourse.llvm.org/t/standard-dialect-the-final-chapter/6061 Differential Revision: https://reviews.llvm.org/D120624
2022-01-19[mlir] Make locations required when adding/creating block argumentsRiver Riddle
BlockArguments gained the ability to have locations attached a while ago, but they have always been optional. This goes against the core tenant of MLIR where location information is a requirement, so this commit updates the API to require locations. Fixes #53279 Differential Revision: https://reviews.llvm.org/D117633
2022-01-18[mlir][Pass] Deprecate FunctionPass in favor of OperationPass<FuncOp>River Riddle
The only benefit of FunctionPass is that it filters out function declarations. This isn't enough to justify carrying it around, as we can simplify filter out declarations when necessary within the pass. We can also explore with better scheduling primitives to filter out declarations at the pipeline level in the future. The definition of FunctionPass is left intact for now to allow time for downstream users to migrate. Differential Revision: https://reviews.llvm.org/D117182
2022-01-02Apply clang-tidy fixes for performance-for-range-copy to MLIR (NFC)Mehdi Amini
2021-12-20[mlir] Switching accessors to prefixed form (NFC)Jacques Pienaar
Makes eventual prefixing flag flip smaller change.
2021-10-13[MLIR] Replace std ops with arith dialect opsMogball
Precursor: https://reviews.llvm.org/D110200 Removed redundant ops from the standard dialect that were moved to the `arith` or `math` dialects. Renamed all instances of operations in the codebase and in tests. Reviewed By: rriddle, jpienaar Differential Revision: https://reviews.llvm.org/D110797
2021-09-21[MLIR][SCF] Add for-to-while loop transformation passMorten Borup Petersen
This pass transforms SCF.ForOp operations to SCF.WhileOp. The For loop condition is placed in the 'before' region of the while operation, and indctuion variable incrementation + the loop body in the 'after' region. The loop carried values of the while op are the induction variable (IV) of the for-loop + any iter_args specified for the for-loop. Any 'yield' ops in the for-loop are rewritten to additionally yield the (incremented) induction variable. This transformation is useful for passes where we want to consider structured control flow solely on the basis of a loop body and the computation of a loop condition. As an example, when doing high-level synthesis in CIRCT, the incrementation of an IV in a for-loop is "just another part" of a circuit datapath, and what we really care about is the distinction between our datapath and our control logic (the condition variable). Differential Revision: https://reviews.llvm.org/D108454
2021-09-20Revert "[MLIR][SCF] Add for-to-while loop transformation pass"Mehdi Amini
This reverts commit 644b55d57ec76a18916d30f921781b99795f6e10. The added test is failing the bots.
2021-09-20[MLIR][SCF] Add for-to-while loop transformation passMorten Borup Petersen
This pass transforms SCF.ForOp operations to SCF.WhileOp. The For loop condition is placed in the 'before' region of the while operation, and indctuion variable incrementation + the loop body in the 'after' region. The loop carried values of the while op are the induction variable (IV) of the for-loop + any iter_args specified for the for-loop. Any 'yield' ops in the for-loop are rewritten to additionally yield the (incremented) induction variable. This transformation is useful for passes where we want to consider structured control flow solely on the basis of a loop body and the computation of a loop condition. As an example, when doing high-level synthesis in CIRCT, the incrementation of an IV in a for-loop is "just another part" of a circuit datapath, and what we really care about is the distinction between our datapath and our control logic (the condition variable). Differential Revision: https://reviews.llvm.org/D108454