A concatenation of empty tensors can be replaced by a single empty
tensor of the concatenated shape. Add this pattern to
`populateFoldTensorEmptyPatterns`.
This is useful for transformations such as bufferization, which is looking for tensor.extract_slice/insert_slice pairs.
Also fix the documentation of the corresponding tranform op.
Differential Revision: https://reviews.llvm.org/D152455
This change adds a new helper function `mlir::reifyResultShapes` that calls the corresponding interface method and also checks the result produced by the implementation when running in debug mode. Bugs due to incorrect interface implementations can be difficult to debug.
This helper function also reduces the amount of code needed at call sites: the cast to `ReifyRankedShapedTypeOpInterface` is done in the helper function.
Differential Revision: https://reviews.llvm.org/D145777
`reifyResultShapes` now returns `OpFoldResult`s instead of `Value`s. This is often more efficient because many transformations immediately attempt to extract a constant from the reified values.
Differential Revision: https://reviews.llvm.org/D145250
At the moment, they are a part of EmptyOp::getCanonicalizationPatterns. When
extract_slice(tensor.empty) is rewritten as a new tensor.empty, it could
happen that we end up with two tensor.empty ops, since the original
tensor.empty can have two users. After bufferization such cases result in two
allocations.
Differential Revision: https://reviews.llvm.org/D139308
