The structure of the code has changed a while ago and the code was not updated properly.
There is no test case for this because we do currently not have an op
that could trigger this bug.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D139838
tensor.empty op elimination is an optimization that brings IR in a more bufferization-friendly form. E.g.:
```
%0 = tensor.empty()
%1 = linalg.fill(%cst, %0) {inplace = [true]}
%2 = tensor.insert_slice %1 into %t[10][20][1]
```
Is rewritten to:
```
%0 = tensor.extract_slice %t[10][20][1]
%1 = linalg.fill(%cst, %0) {inplace = [true]}
%2 = tensor.insert_slice %1 into %t[10][20][1]
```
This optimization used to operate on bufferization.alloc_tensor ops. This is not correct because the documentation of bufferization.alloc_tensor says that it always bufferizes to an allocation. Instead, this optimization should operate on tensor.empty ops, which can then be lowered to bufferization.alloc_tensor ops (if they don't get eliminated).
Differential Revision: https://reviews.llvm.org/D137162
