Revert "[mlir python] Add nanobind support for standalone dialects." (llvm#118517)

Reverts llvm#117922 because deps aren't met on some of the
post-commit build bots.

Author: makslevental

mlir/cmake/modules/AddMLIRPython.cmake

@@ -114,11 +114,10 @@ endfunction()
 #   EMBED_CAPI_LINK_LIBS: Dependent CAPI libraries that this extension depends
 #     on. These will be collected for all extensions and put into an
 #     aggregate dylib that is linked against.
-#   PYTHON_BINDINGS_LIBRARY: Either pybind11 or nanobind.
 function(declare_mlir_python_extension name)
   cmake_parse_arguments(ARG
     ""
-    "ROOT_DIR;MODULE_NAME;ADD_TO_PARENT;PYTHON_BINDINGS_LIBRARY"
+    "ROOT_DIR;MODULE_NAME;ADD_TO_PARENT"
     "SOURCES;PRIVATE_LINK_LIBS;EMBED_CAPI_LINK_LIBS"
     ${ARGN})
 
@@ -127,20 +126,15 @@ function(declare_mlir_python_extension name)
   endif()
   set(_install_destination "src/python/${name}")
 
-  if(NOT ARG_PYTHON_BINDINGS_LIBRARY)
-    set(ARG_PYTHON_BINDINGS_LIBRARY "pybind11")
-  endif()
-
   add_library(${name} INTERFACE)
   set_target_properties(${name} PROPERTIES
     # Yes: Leading-lowercase property names are load bearing and the recommended
     # way to do this: https://gitlab.kitware.com/cmake/cmake/-/issues/19261
-    EXPORT_PROPERTIES "mlir_python_SOURCES_TYPE;mlir_python_EXTENSION_MODULE_NAME;mlir_python_EMBED_CAPI_LINK_LIBS;mlir_python_DEPENDS;mlir_python_BINDINGS_LIBRARY"
+    EXPORT_PROPERTIES "mlir_python_SOURCES_TYPE;mlir_python_EXTENSION_MODULE_NAME;mlir_python_EMBED_CAPI_LINK_LIBS;mlir_python_DEPENDS"
     mlir_python_SOURCES_TYPE extension
     mlir_python_EXTENSION_MODULE_NAME "${ARG_MODULE_NAME}"
     mlir_python_EMBED_CAPI_LINK_LIBS "${ARG_EMBED_CAPI_LINK_LIBS}"
     mlir_python_DEPENDS ""
-    mlir_python_BINDINGS_LIBRARY "${ARG_PYTHON_BINDINGS_LIBRARY}"
   )
 
   # Set the interface source and link_libs properties of the target
@@ -229,14 +223,12 @@ function(add_mlir_python_modules name)
     elseif(_source_type STREQUAL "extension")
       # Native CPP extension.
       get_target_property(_module_name ${sources_target} mlir_python_EXTENSION_MODULE_NAME)
-      get_target_property(_bindings_library ${sources_target} mlir_python_BINDINGS_LIBRARY)
       # Transform relative source to based on root dir.
       set(_extension_target "${modules_target}.extension.${_module_name}.dso")
       add_mlir_python_extension(${_extension_target} "${_module_name}"
         INSTALL_COMPONENT ${modules_target}
         INSTALL_DIR "${ARG_INSTALL_PREFIX}/_mlir_libs"
         OUTPUT_DIRECTORY "${ARG_ROOT_PREFIX}/_mlir_libs"
-        PYTHON_BINDINGS_LIBRARY ${_bindings_library}
         LINK_LIBS PRIVATE
           ${sources_target}
           ${ARG_COMMON_CAPI_LINK_LIBS}
@@ -642,7 +634,7 @@ endfunction()
 function(add_mlir_python_extension libname extname)
   cmake_parse_arguments(ARG
   ""
-  "INSTALL_COMPONENT;INSTALL_DIR;OUTPUT_DIRECTORY;PYTHON_BINDINGS_LIBRARY"
+  "INSTALL_COMPONENT;INSTALL_DIR;OUTPUT_DIRECTORY"
   "SOURCES;LINK_LIBS"
   ${ARGN})
   if(ARG_UNPARSED_ARGUMENTS)
@@ -652,16 +644,9 @@ function(add_mlir_python_extension libname extname)
   # The actual extension library produces a shared-object or DLL and has
   # sources that must be compiled in accordance with pybind11 needs (RTTI and
   # exceptions).
-  if(NOT DEFINED ARG_PYTHON_BINDINGS_LIBRARY OR ARG_PYTHON_BINDINGS_LIBRARY STREQUAL "pybind11")
-    pybind11_add_module(${libname}
-      ${ARG_SOURCES}
-    )
-  elseif(ARG_PYTHON_BINDINGS_LIBRARY STREQUAL "nanobind")
-    nanobind_add_module(${libname}
-      NB_DOMAIN mlir
-      ${ARG_SOURCES}
-    )
-  endif()
+  pybind11_add_module(${libname}
+    ${ARG_SOURCES}
+  )
 
   # The extension itself must be compiled with RTTI and exceptions enabled.
   # Also, some warning classes triggered by pybind11 are disabled.

mlir/cmake/modules/MLIRDetectPythonEnv.cmake

@@ -21,12 +21,6 @@ macro(mlir_configure_python_dev_packages)
 
     find_package(Python3 ${LLVM_MINIMUM_PYTHON_VERSION}
       COMPONENTS Interpreter ${_python_development_component} REQUIRED)
-
-    # It's a little silly to detect Python a second time, but nanobind's cmake
-    # code looks for Python_ not Python3_.
-    find_package(Python ${LLVM_MINIMUM_PYTHON_VERSION}
-      COMPONENTS Interpreter ${_python_development_component} REQUIRED)
-
     unset(_python_development_component)
     message(STATUS "Found python include dirs: ${Python3_INCLUDE_DIRS}")
     message(STATUS "Found python libraries: ${Python3_LIBRARIES}")
@@ -37,13 +31,6 @@ macro(mlir_configure_python_dev_packages)
     message(STATUS "Python prefix = '${PYTHON_MODULE_PREFIX}', "
                   "suffix = '${PYTHON_MODULE_SUFFIX}', "
                   "extension = '${PYTHON_MODULE_EXTENSION}")
-
-    mlir_detect_nanobind_install()
-    find_package(nanobind 2.2 CONFIG REQUIRED)
-    message(STATUS "Found nanobind v${nanobind_VERSION}: ${nanobind_INCLUDE_DIR}")
-    message(STATUS "Python prefix = '${PYTHON_MODULE_PREFIX}', "
-                  "suffix = '${PYTHON_MODULE_SUFFIX}', "
-                  "extension = '${PYTHON_MODULE_EXTENSION}")
   endif()
 endmacro()
 
@@ -71,29 +58,3 @@ function(mlir_detect_pybind11_install)
     set(pybind11_DIR "${PACKAGE_DIR}" PARENT_SCOPE)
   endif()
 endfunction()
-
-
-# Detects a nanobind package installed in the current python environment
-# and sets variables to allow it to be found. This allows nanobind to be
-# installed via pip, which typically yields a much more recent version than
-# the OS install, which will be available otherwise.
-function(mlir_detect_nanobind_install)
-  if(nanobind_DIR)
-    message(STATUS "Using explicit nanobind cmake directory: ${nanobind_DIR} (-Dnanobind_DIR to change)")
-  else()
-    message(STATUS "Checking for nanobind in python path...")
-    execute_process(
-      COMMAND "${Python3_EXECUTABLE}"
-      -c "import nanobind;print(nanobind.cmake_dir(), end='')"
-      WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
-      RESULT_VARIABLE STATUS
-      OUTPUT_VARIABLE PACKAGE_DIR
-      ERROR_QUIET)
-    if(NOT STATUS EQUAL "0")
-      message(STATUS "not found (install via 'pip install nanobind' or set nanobind_DIR)")
-      return()
-    endif()
-    message(STATUS "found (${PACKAGE_DIR})")
-    set(nanobind_DIR "${PACKAGE_DIR}" PARENT_SCOPE)
-  endif()
-endfunction()

mlir/docs/Bindings/Python.md

@@ -1138,14 +1138,12 @@ attributes and types must connect to the relevant C APIs for building and
 inspection, which must be provided first. Bindings for `Attribute` and `Type`
 subclasses can be defined using
 [`include/mlir/Bindings/Python/PybindAdaptors.h`](https://github.com/llvm/llvm-project/blob/main/mlir/include/mlir/Bindings/Python/PybindAdaptors.h)
-or
-[`include/mlir/Bindings/Python/NanobindAdaptors.h`](https://github.com/llvm/llvm-project/blob/main/mlir/include/mlir/Bindings/Python/NanobindAdaptors.h)
-utilities that mimic pybind11/nanobind API for defining functions and
-properties. These bindings are to be included in a separate module. The
-utilities also provide automatic casting between C API handles `MlirAttribute`
-and `MlirType` and their Python counterparts so that the C API handles can be
-used directly in binding implementations. The methods and properties provided by
-the bindings should follow the principles discussed above.
+utilities that mimic pybind11 API for defining functions and properties. These
+bindings are to be included in a separate pybind11 module. The utilities also
+provide automatic casting between C API handles `MlirAttribute` and `MlirType`
+and their Python counterparts so that the C API handles can be used directly in
+binding implementations. The methods and properties provided by the bindings
+should follow the principles discussed above.
 
 The attribute and type bindings for a dialect can be located in
 `lib/Bindings/Python/Dialect<Name>.cpp` and should be compiled into a separate
@@ -1181,9 +1179,7 @@ make the passes available along with the dialect.
 Dialect functionality other than IR objects or passes, such as helper functions,
 can be exposed to Python similarly to attributes and types. C API is expected to
 exist for this functionality, which can then be wrapped using pybind11 and
-`[include/mlir/Bindings/Python/PybindAdaptors.h](https://github.com/llvm/llvm-project/blob/main/mlir/include/mlir/Bindings/Python/PybindAdaptors.h)`,
-or nanobind and
-`[include/mlir/Bindings/Python/NanobindAdaptors.h](https://github.com/llvm/llvm-project/blob/main/mlir/include/mlir/Bindings/Python/NanobindAdaptors.h)`
+`[include/mlir/Bindings/Python/PybindAdaptors.h](https://github.com/llvm/llvm-project/blob/main/mlir/include/mlir/Bindings/Python/PybindAdaptors.h)`
 utilities to connect to the rest of Python API. The bindings can be located in a
-separate module or in the same module as attributes and types, and
+separate pybind11 module or in the same module as attributes and types, and
 loaded along with the dialect.

mlir/examples/standalone/python/CMakeLists.txt

@@ -17,32 +17,18 @@ declare_mlir_dialect_python_bindings(
   ROOT_DIR "${CMAKE_CURRENT_SOURCE_DIR}/mlir_standalone"
   TD_FILE dialects/StandaloneOps.td
   SOURCES
-    dialects/standalone_pybind11.py
-    dialects/standalone_nanobind.py
+    dialects/standalone.py
   DIALECT_NAME standalone)
 
-
-declare_mlir_python_extension(StandalonePythonSources.Pybind11Extension
-  MODULE_NAME _standaloneDialectsPybind11
-  ADD_TO_PARENT StandalonePythonSources
-  SOURCES
-    StandaloneExtensionPybind11.cpp
-  EMBED_CAPI_LINK_LIBS
-    StandaloneCAPI
-  PYTHON_BINDINGS_LIBRARY pybind11
-)
-
-declare_mlir_python_extension(StandalonePythonSources.NanobindExtension
-  MODULE_NAME _standaloneDialectsNanobind
+declare_mlir_python_extension(StandalonePythonSources.Extension
+  MODULE_NAME _standaloneDialects
   ADD_TO_PARENT StandalonePythonSources
   SOURCES
-    StandaloneExtensionNanobind.cpp
+    StandaloneExtension.cpp
   EMBED_CAPI_LINK_LIBS
     StandaloneCAPI
-  PYTHON_BINDINGS_LIBRARY nanobind
 )
 
-
 ################################################################################
 # Common CAPI
 ################################################################################

mlir/examples/standalone/python/StandaloneExtensionPybind11.cpp renamed to mlir/examples/standalone/python/StandaloneExtension.cpp

@@ -1,7 +1,4 @@
-//===- StandaloneExtensionPybind11.cpp - Extension module -----------------===//
-//
-// This is the pybind11 version of the example module. There is also a nanobind
-// example in StandaloneExtensionNanobind.cpp.
+//===- StandaloneExtension.cpp - Extension module -------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
@@ -14,7 +11,7 @@
 
 using namespace mlir::python::adaptors;
 
-PYBIND11_MODULE(_standaloneDialectsPybind11, m) {
+PYBIND11_MODULE(_standaloneDialects, m) {
   //===--------------------------------------------------------------------===//
   // standalone dialect
   //===--------------------------------------------------------------------===//

mlir/examples/standalone/python/StandaloneExtensionNanobind.cpp

@@ -3,4 +3,4 @@
 #  SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
 from ._standalone_ops_gen import *
-from .._mlir_libs._standaloneDialectsNanobind.standalone import *
+from .._mlir_libs._standaloneDialects.standalone import *

mlir/examples/standalone/python/mlir_standalone/dialects/standalone_nanobind.py renamed to mlir/examples/standalone/python/mlir_standalone/dialects/standalone.py

@@ -1,17 +1,7 @@
-# RUN: %python %s pybind11 | FileCheck %s
-# RUN: %python %s nanobind | FileCheck %s
+# RUN: %python %s | FileCheck %s
 
-import sys
 from mlir_standalone.ir import *
-from mlir_standalone.dialects import builtin as builtin_d
-
-if sys.argv[1] == "pybind11":
-    from mlir_standalone.dialects import standalone_pybind11 as standalone_d
-elif sys.argv[1] == "nanobind":
-    from mlir_standalone.dialects import standalone_nanobind as standalone_d
-else:
-    raise ValueError("Expected either pybind11 or nanobind as arguments")
-
+from mlir_standalone.dialects import builtin as builtin_d, standalone as standalone_d
 
 with Context():
     standalone_d.register_dialect()