[all-commits] [llvm/llvm-project] a38381: [mlir][Vector] Add a rewrite pattern for gather ov...

[Andrzej Warzyński via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: a383817b7e24d948dd5e342e8df8d12d0f15d536
      https://github.com/llvm/llvm-project/commit/a383817b7e24d948dd5e342e8df8d12d0f15d536
  Author: Andrzej Warzyński <andrzej.warzynski at arm.com>
  Date:   2023-11-30 (Thu, 30 Nov 2023)

  Changed paths:
    M mlir/lib/Dialect/Vector/Transforms/LowerVectorGather.cpp
    M mlir/test/Dialect/Vector/vector-gather-lowering.mlir

  Log Message:
  -----------
  [mlir][Vector] Add a rewrite pattern for gather over a strided memref (#72991)

This patch adds a rewrite pattern for `vector.gather` over a strided
memref like the following:

```mlir
%subview = memref.subview %arg0[0, 0] [100, 1] [1, 1] :
    memref<100x3xf32> to memref<100xf32, strided<[3]>>
%gather = vector.gather %subview[%c0] [%idxs], %cst_0, %cst :
    memref<100xf32, strided<[3]>>, vector<4xindex>, vector<4xi1>, vector<4xf32>
    into vector<4xf32>
```

After the pattern added in this patch:
```mlir
%collapse_shape = memref.collapse_shape %arg0 [[0, 1]] :
    memref<100x3xf32> into memref<300xf32>
%1 = arith.muli %arg3, %cst : vector<4xindex>
%gather = vector.gather %collapse_shape[%c0] [%1], %cst_1, %cst_0 :
    memref<300xf32>, vector<4xindex>, vector<4xi1>, vector<4xf32>
    into vector<4xf32>
```

Fixes https://github.com/openxla/iree/issues/15364.