Maksim Levental 18fc908566
[mlir][Python] move IRTypes and IRAttributes to MLIRPythonSupport (#174118)
This PR continues the work of
https://github.com/llvm/llvm-project/pull/171775 by moving more useful
types/attributes into MLIRPythonSupport.

You can now do 

```c++
struct PyTestIntegerRankedTensorType
    : mlir::python::MLIR_BINDINGS_PYTHON_DOMAIN::PyConcreteType<
          PyTestIntegerRankedTensorType,
          mlir::python::MLIR_BINDINGS_PYTHON_DOMAIN::PyRankedTensorType>
struct PyTestTensorValue
    : mlir::python::MLIR_BINDINGS_PYTHON_DOMAIN::PyConcreteValue<
          PyTestTensorValue>
```
instead of `mlir_type_subclass` and `mlir_value_subclass`;
**specifically manual registration of the "value caster" via indirection
through the Python interpreter is no longer necessary** . You can also
now freely use all such types at the nanobind API level (e.g., overload
based on `FP*`):

```c++
using mlir::python::MLIR_BINDINGS_PYTHON_DOMAIN;
standaloneM.def("print_fp_type", [](PyF16Type &) { nb::print("this is a fp16 type"); });
standaloneM.def("print_fp_type", [](PyF32Type &) { nb::print("this is a fp32 type"); });
standaloneM.def("print_fp_type", [](PyF64Type &) { nb::print("this is a fp64 type"); });
```

Note, here we only port `PythonTestModuleNanobind` but there is a
follow-up PR that ports **all** in-tree dialect extensions
https://github.com/llvm/llvm-project/pull/174156 to use these. After
that one we can soft deprecate `mlir_pure_subclass`.

Note, depends on https://github.com/llvm/llvm-project/pull/171775
2026-01-05 09:34:58 -08:00
..

An out-of-tree MLIR dialect

This is an example of an out-of-tree MLIR dialect along with a standalone opt-like tool to operate on that dialect.

Building - Component Build

This setup assumes that you have built LLVM and MLIR in $BUILD_DIR and installed them to $PREFIX. To build and launch the tests, run

mkdir build && cd build
cmake -G Ninja .. -DMLIR_DIR=$PREFIX/lib/cmake/mlir -DLLVM_EXTERNAL_LIT=$BUILD_DIR/bin/llvm-lit
cmake --build . --target check-standalone

To build the documentation from the TableGen description of the dialect operations, run

cmake --build . --target mlir-doc

Note: Make sure to pass -DLLVM_INSTALL_UTILS=ON when building LLVM with CMake in order to install FileCheck to the chosen installation prefix.

Building - Monolithic Build

This setup assumes that you build the project as part of a monolithic LLVM build via the LLVM_EXTERNAL_PROJECTS mechanism. To build LLVM, MLIR, the example and launch the tests run

mkdir build && cd build
cmake -G Ninja `$LLVM_SRC_DIR/llvm` \
    -DCMAKE_BUILD_TYPE=Release \
    -DLLVM_TARGETS_TO_BUILD=host \
    -DLLVM_ENABLE_PROJECTS=mlir \
    -DLLVM_EXTERNAL_PROJECTS=standalone-dialect -DLLVM_EXTERNAL_STANDALONE_DIALECT_SOURCE_DIR=../
cmake --build . --target check-standalone

Here, $LLVM_SRC_DIR needs to point to the root of the monorepo.