[mlir][tensor][bufferize] tensor.empty bufferizes to allocation

[matthias-springer]

BufferizableOpInterface::bufferizesToAllocation is queried when forming equivalence sets during bufferization. It is not really needed for ops like tensor.empty which do not have tensor operands, but it should be added for consistency.

This change should have been part of #68080. No test is added because the return value of this function is irrelevant for ops without tensor operands. (However, this function acts as a form documentation, describing the bufferization semantics of the op.)

[llvmbot]

@llvm/pr-subscribers-mlir

@llvm/pr-subscribers-mlir-tensor

Changes

BufferizableOpInterface::bufferizesToAllocation is queried when forming equivalence sets during bufferization. It is not really needed for ops like tensor.empty which do not have tensor operands, but it should be added for consistency.

This change should have been part of #68080. No test is added because the return value of this function is irrelevant for ops without tensor operands. (However, this function acts as a form documentation, describing the bufferization semantics of the op.)

---

Full diff: https://github.com/llvm/llvm-project/pull/68201.diff

1 Files Affected:

• (modified) mlir/lib/Dialect/Tensor/Transforms/BufferizableOpInterfaceImpl.cpp (+2)

diff --git a/mlir/lib/Dialect/Tensor/Transforms/BufferizableOpInterfaceImpl.cpp b/mlir/lib/Dialect/Tensor/Transforms/BufferizableOpInterfaceImpl.cpp
index b08283f0070784c..997e442bc9ae241 100644
--- a/mlir/lib/Dialect/Tensor/Transforms/BufferizableOpInterfaceImpl.cpp
+++ b/mlir/lib/Dialect/Tensor/Transforms/BufferizableOpInterfaceImpl.cpp
@@ -260,6 +260,8 @@ struct DimOpInterface
 struct EmptyOpInterface
     : public BufferizableOpInterface::ExternalModel<EmptyOpInterface,
                                                     tensor::EmptyOp> {
+  bool bufferizesToAllocation(Operation *op, Value value) const { return true; }
+
   bool resultBufferizesToMemoryWrite(Operation *op, OpResult opResult,
                                      const AnalysisState &state) const {
     // The returned tensor does not have specified contents.