[mlir] Register Linalg passes in C API and Python Bindings

[ftynse]

Summary

Provide a registration mechanism for Linalg dialect-specific passes in C
API and Python bindings. These are being built into the dialect library
but exposed in separate headers (C) or modules (Python).

mlir/include/mlir-c/Dialect/Linalg.h

 //===-- mlir-c/Dialect/Linalg.h - C API for Linalg dialect --------*- C -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM
 // Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef MLIR_C_DIALECT_LINALG_H
 #define MLIR_C_DIALECT_LINALG_H
 
 #include "mlir-c/Registration.h"
+#include "mlir-c/Support.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 MLIR_DECLARE_CAPI_DIALECT_REGISTRATION(Linalg, linalg);
 
 #ifdef __cplusplus
 }
 #endif
 
+#include "mlir/Dialect/Linalg/Passes.capi.h.inc"
+
 #endif // MLIR_C_DIALECT_LINALG_H

mlir/include/mlir/Dialect/Linalg/CMakeLists.txt

 add_subdirectory(IR)
 
 set(LLVM_TARGET_DEFINITIONS Passes.td)
 mlir_tablegen(Passes.h.inc -gen-pass-decls -name Linalg)
+mlir_tablegen(Passes.capi.h.inc -gen-pass-capi-header --prefix Linalg)
+mlir_tablegen(Passes.capi.cpp.inc -gen-pass-capi-impl --prefix Linalg)
 add_public_tablegen_target(MLIRLinalgPassIncGen)
 
 add_mlir_doc(Passes -gen-pass-doc LinalgPasses ./)

mlir/lib/Bindings/Python/CMakeLists.txt

if (NOT LLVM_ENABLE_IDE)
   add_llvm_install_targets(
     install-MLIRBindingsPythonDialects
     DEPENDS MLIRBindingsPythonSources
     COMPONENT MLIRBindingsPythonDialects)
 endif()
 
 add_subdirectory(Transforms)
 add_subdirectory(Conversions)
+
+add_mlir_python_extension(MLIRLinalgPassesBindingsPythonExtension _mlirLinalgPasses
+  INSTALL_DIR
+    python
+  SOURCES
+    LinalgPasses.cpp
+)
+add_dependencies(MLIRBindingsPythonExtension MLIRLinalgPassesBindingsPythonExtension)

mlir/lib/Bindings/Python/LinalgPasses.cpp

+//===- LinalgPasses.cpp - Pybind module for the Linalg passes -------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir-c/Dialect/Linalg.h"
+
+#include <pybind11/pybind11.h>
+
+// -----------------------------------------------------------------------------
+// Module initialization.
+// -----------------------------------------------------------------------------
+
+PYBIND11_MODULE(_mlirLinalgPasses, m) {
+  m.doc() = "MLIR Linalg Dialect Passes";
+
+  // Register all Linalg passes on load.
+  mlirRegisterLinalgPasses();
+}

mlir/lib/Bindings/Python/mlir/dialects/linalg/passes/__init__.py

+#  Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+#  See https://llvm.org/LICENSE.txt for license information.
+#  SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+from ...._cext_loader import _load_extension
+_cextLinalgPasses = _load_extension("_mlirLinalgPasses")

mlir/lib/CAPI/Dialect/CMakeLists.txt

 # TODO: Make the check source feature optional as an argument on *_add_library.
 set(LLVM_OPTIONAL_SOURCES
   Linalg.cpp
+  LinalgPasses.cpp
   SCF.cpp
   Shape.cpp
   Standard.cpp
   Tensor.cpp
 )
 
 add_mlir_public_c_api_library(MLIRCAPILinalg
   Linalg.cpp
+  LinalgPasses.cpp
+
+  DEPENDS
+  MLIRLinalgPassIncGen
 
   LINK_LIBS PUBLIC
   MLIRCAPIIR
   MLIRLinalg
+  MLIRPass
+  MLIRLinalgTransforms
 )
 
 add_mlir_public_c_api_library(MLIRCAPISCF
   SCF.cpp
 
   LINK_LIBS PUBLIC
   MLIRCAPIIR
   MLIRSCF

mlir/lib/CAPI/Dialect/LinalgPasses.cpp

+//===- LinalgPasses.cpp - C API for Linalg Dialect Passes -----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/CAPI/Pass.h"
+#include "mlir/Dialect/Linalg/Passes.h"
+#include "mlir/Pass/Pass.h"
+
+// Must include the declarations as they carry important visibility attributes.
+#include "mlir/Dialect/Linalg/Passes.capi.h.inc"
+
+using namespace mlir;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "mlir/Dialect/Linalg/Passes.capi.cpp.inc"
+
+#ifdef __cplusplus
+}
+#endif