[Mlir-commits] [mlir] [mlir] [linalg] Add canonicalize pattern to swap transpose with broadcast (PR #97063)

[donald chen]

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@@ -243,6 +243,14 @@ SmallVector<int64_t>
 computePermutationVector(int64_t permSize, ArrayRef<int64_t> positions,
                          ArrayRef<int64_t> desiredPositions);
 
+/// Returns a permutation vector that remove the result position in
+/// removePositions from inputPerm.
+///
+/// For example, inputPerm = {2, 4, 0, 1, 3} and removePositions = {1, 2} would
+/// result in a {2, 0, 1} permutation vector.
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cxy-1993 wrote:

Thank you for your suggestion, this approach is very interesting (at least my function name is not precise enough, I think dropResults would be better). We can indeed replace the calculation of perm with the calculation of affine map using applyPermutationMap and getPermutationMap. Before making the changes, I would like to discuss some points: This will simplify the calculation of perm, but it will introduce more compilation time -- we have to construct affine maps to reuse the affine map operation functions. Is this a more reasonable approach? If so, all the util functions in the Permutation utils series have corresponding util functions in the affine map. Should we systematically replace them all?

https://github.com/llvm/llvm-project/pull/97063