[all-commits] [llvm/llvm-project] 0bfbec: [mlir][TransformDialect] Simplify the lowering of ...

[qcolombet via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 0bfbecf52e8fa04785cf0b5c38b25c13442fb53d
      https://github.com/llvm/llvm-project/commit/0bfbecf52e8fa04785cf0b5c38b25c13442fb53d
  Author: Quentin Colombet <quentin.colombet at gmail.com>
  Date:   2023-04-13 (Thu, 13 Apr 2023)

  Changed paths:
    M mlir/include/mlir/Dialect/Tensor/IR/TensorOps.td
    M mlir/include/mlir/Dialect/Utils/IndexingUtils.h
    M mlir/include/mlir/Dialect/Utils/ReshapeOpsUtils.h
    M mlir/lib/Dialect/Linalg/TransformOps/LinalgTransformOps.cpp
    M mlir/lib/Dialect/Tensor/IR/TensorOps.cpp
    M mlir/lib/Dialect/Utils/IndexingUtils.cpp
    M mlir/lib/Dialect/Utils/ReshapeOpsUtils.cpp
    M mlir/test/Dialect/Linalg/transform-lower-pack.mlir

  Log Message:
  -----------
  [mlir][TransformDialect] Simplify the lowering of pack/unpack when these are just pad/unpad

This patch recognizes when tensor.pack/unpack operations are simple
tensor.pad/unpad (a.k.a. tensor.extract_slice) and lowers them in a simpler
sequence of instruction.

For pack, instead of doing:
```
pad
expand_shape
transpose
```
we do
```
pad
insert_slice
```

For unpack, instead of doing:
```
transpose
collapse_shape
extract_slice
```
we do
```
extract_slice
```

Note: returning nullptr for the transform dialect is fine. The related
handles are just ignored by the following transformation.

Differential Revision: https://reviews.llvm.org/D148159