llvm-project

b4c31dc9 - [mlir][Vector] add vector.insert canonicalization pattern to convert a chain of insertions to vector.from_elements (#142944)

[mlir][Vector] add vector.insert canonicalization pattern to convert a chain of insertions to vector.from_elements (#142944) ## Description This change introduces a new canonicalization pattern for the MLIR Vector dialect that optimizes chains of insertions. The optimization identifies when a vector is **completely** initialized through a series of vector.insert operations and replaces the entire chain with a single `vector.from_elements` operation. Please be aware that the new pattern **doesn't** work for poison vectors where only **some** elements are set, as MLIR doesn't support partial poison vectors for now. **New Pattern: InsertChainFullyInitialized** * Detects chains of vector.insert operations. * Validates that all insertions are at static positions, and all intermediate insertions have only one use. * Ensures the entire vector is **completely** initialized. * Replaces the entire chain with a single vector.from_elementts operation. **Refactored Helper Function** * Extracted `calculateInsertPosition` from `foldDenseElementsAttrDestInsertOp` to avoid code duplication. ## Example ``` // Before: %v1 = vector.insert %c10, %v0[0] : i64 into vector<2xi64> %v2 = vector.insert %c20, %v1[1] : i64 into vector<2xi64> // After: %v2 = vector.from_elements %c10, %c20 : vector<2xi64> ``` It also works for multidimensional vectors. ``` // Before: %v1 = vector.insert %cv0, %v0[0] : vector<3xi64> into vector<2x3xi64> %v2 = vector.insert %cv1, %v1[1] : vector<3xi64> into vector<2x3xi64> // After: %0:3 = vector.to_elements %arg1 : vector<3xi64> %1:3 = vector.to_elements %arg2 : vector<3xi64> %v2 = vector.from_elements %0#0, %0#1, %0#2, %1#0, %1#1, %1#2 : vector<2x3xi64> ``` --------- Co-authored-by: Yang Bai <yangb@nvidia.com> Co-authored-by: Andrzej Warzyński <andrzej.warzynski@gmail.com>