The given test fails due to error below.
The following error is why the test is failing. One `memref.store` and two `memref.load` are consumers of the loop index for which I do RAUW. `memref.store` is first in the list. If I RAUW on this the loop of `llvm::make early inc range(threadIdx.getUsers())` does not return two `memref.load` as users. They remain unchanged. I'm not really certain why.
This change applies RAUW after collecting the users. If a better solution exists, I would be happy to implement it.
```
mlir-opt: ...llvm-project/mlir/include/mlir/IR/UseDefLists.h:175: mlir::IRObjectWithUseList<mlir::OpOperand>::~IRObjectWithUseList() [OperandType = mlir::OpOperand]: Assertion `use_empty() && "Cannot destroy a value that still has uses!"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
```
Reviewed By: springerm
Differential Revision: https://reviews.llvm.org/D138029
Previously, the need for a dense permutation leaked into the thread_dim_mapping specification.
This revision allows to use a sparse specification of the thread_dim_mapping and the proper completion / sorting is applied automatically.
In the process, the sematics of scf.foreach_thread is tightened to require a matching number of thread dimensions and mappings.
The relevant negative test is added.
Differential Revision: https://reviews.llvm.org/D137906
`scf.foreach_thread` defines mapping its loops to processors via an integer array, see an example below. A lowering can use this mapping. However, expressing mapping as an integer array is very confusing, especially when there are multiple levels of parallelism. In addition, the op does not verify the integer array. This change introduces device mapping attribute to make mapping descriptive and verifiable. Then it makes GPU transform dialect use it.
```
scf.foreach_thread (%i, %j) in (%c1, %c2) {
scf.foreach_thread (%i2, %j2) in (%c1, %c2)
{...} { thread_dim_mapping = [0, 1]}
} { thread_dim_mapping = [0, 1]}
```
It first introduces a `DeviceMappingInterface` which is an attribute interface. `scf.foreach_thread` defines its mapping via this interface. A lowering must define its attributes and implement this interface as well. This way gives us a clear validation.
The change also introduces two new attributes (`#gpu.thread<x/y/z>` and `#gpu.block<x,y,z>` ). After this change, the above code prints as below, as seen here, this way clarifies the loop mappings. The change also implements consuming of these two new attribute by the transform dialect. Transform dialect binds the outermost loops to the thread blocks and innermost loops to threads.
```
scf.foreach_thread (%i, %j) in (%c1, %c2) {
scf.foreach_thread (%i2, %j2) in (%c1, %c2)
{...} { thread_dim_mapping = [#gpu.thread<x>, #gpu.thread<y>]}
} { thread_dim_mapping = [#gpu.block<x>, #gpu.block<y>]}
```
Reviewed By: ftynse, nicolasvasilache
Differential Revision: https://reviews.llvm.org/D137413
Many tests wrap the piece of the IR related to the transform dialect
into `transform.with_pdl_patterns` without actually using PDL patterns
inside. Some of these are leftovers from migration to `structured.match`
and some others are cargo cult, both are useless and pollute the tests.
Reviewed By: guraypp
Differential Revision: https://reviews.llvm.org/D135661
Use the recently introduced TransformTypeInterface instead of hardcoding
the PDLOperationType. This will allow the operations to use more
specific transform types to express pre/post-conditions in the future.
It requires the syntax and Python op construction API to be updated.
Dialect extensions will be switched separately.
Reviewed By: nicolasvasilache
Differential Revision: https://reviews.llvm.org/D135584
This revision adds GPU transform dialect. It also introduce a prefix such as "transform.gpu" for all ops related to this dialect.
MLIR already had two GPU transform op in linalg. This revision moves these ops into GPUTransformOps. The Ops are as follows:
`transform.structured.map_nested_foreach_thread_to_gpu_blocks` -> `transform.gpu.map_foreach_to_blocks`
This op selects the outermost (toplevel) foreach_thread and parallelize across GPU blocks. It can also generate `gpu_launch`.
`transform.structured.map_nested_foreach_thread_to_gpu_threads` -> `transform.gpu.map_nested_foreach_to_threads`
This op parallelizes nested foreach_thread that are inside `gpu_launch` across GPU threads.
It doesn't add new functionality, but there are some minor refactoring of the code.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D134800
