[all-commits] [llvm/llvm-project] d1866f: [MLIR] [Linalg] Add option to use the partial view...

[poechsel via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: d1866f89472787dfac92a689700c4c4335a6add3
      https://github.com/llvm/llvm-project/commit/d1866f89472787dfac92a689700c4c4335a6add3
  Author: Pierre Oechsel <pierre.oechsel at gmail.com>
  Date:   2020-05-18 (Mon, 18 May 2020)

  Changed paths:
    M mlir/include/mlir/Dialect/Linalg/Transforms/Transforms.h
    M mlir/include/mlir/Dialect/Vector/EDSC/Intrinsics.h
    M mlir/lib/Dialect/Linalg/Transforms/Promotion.cpp
    M mlir/test/Dialect/Linalg/promote.mlir
    M mlir/test/lib/Transforms/TestLinalgTransforms.cpp

  Log Message:
  -----------
  [MLIR] [Linalg] Add option to use the partial view after promotion.

For now the promoted buffer is indexed using the `full view`. The full view might be
slightly bigger than the partial view (which is accounting for boundaries).
Unfortunately this does not compose easily with other transformations when multiple buffers
with shapes related to each other are involved.
Take `linalg.matmul A B C` (with A of size MxK, B of size KxN and C of size MxN) and suppose we are:
- Tiling over M by 100
- Promoting A only

This is producing a `linalg.matmul promoted_A B subview_C` where `promoted_A` is a promoted buffer
of `A` of size (100xK) and `subview_C` is a subview of size mxK where m could be smaller than 100 due
to boundaries thus leading to a possible incorrect behavior.

We propose to:
- Add a new parameter to the tiling promotion allowing to enable the use of the full tile buffer.
- By default all promoted buffers will be indexed by the partial view.

Note that this could be considered as a breaking change in comparison to the way the tiling promotion
was working.

Differential Revision: https://reviews.llvm.org/D79927