[llvm] [mlir] [mlir][tensor] Fold linalg transpose with tensor pack (PR #74206)

[Han-Chung Wang via llvm-commits]

https://github.com/hanhanW requested changes to this pull request.

Thanks! Few high-level comments:

1. We should match transpose op for linalg.generic form as well. Can you add a `isTranspose(linalg::LinalgOp op)` util to [Linalg/Utils/Utils.h/cpp](https://github.com/llvm/llvm-project/blob/main/mlir/lib/Dialect/Linalg/Utils/Utils.cpp)?
2. Can you add two more tests for pack ops w/o `outer_dim_perms`? For the two new tests, the transpose ops can be in `linalg.generic` form, so we will have enough test coverage.
3. We have some utils for applying permutations. Can you try to use `applyPermutationToVector` and `invertPermutationVector` from [IndexingUtils.h](https://github.com/llvm/llvm-project/blob/main/mlir/include/mlir/Dialect/Utils/IndexingUtils.h)?

https://github.com/llvm/llvm-project/pull/74206