[mlir] Cleanup export of python extensions

[stephenneuendorffer]

Summary

This mostly fixes the operation of the standalone example.
There is still a small issue with mlir-tablegen, which does not
create parent directories of its output file. This can cause
the check-mlir-examples-standalone target to fail from a clean build.

[stephenneuendorffer]

Rolled into D113732

mlir/cmake/modules/AddMLIRPython.cmake

function(declare_mlir_python_sources name)
   add_library(${name} INTERFACE)
   set(_file_depends "${ARG_SOURCES}")
   list(TRANSFORM _file_depends PREPEND "${ARG_ROOT_DIR}/")
   set_target_properties(${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
     # Note that ROOT_DIR and FILE_DEPENDS are not exported because they are
     # only relevant to in-tree uses.
-    EXPORT_PROPERTIES "mlir_python_SOURCES_TYPE;mlir_python_DEST_PREFIX;mlir_python_DEST_PREFIX;mlir_python_SOURCES;mlir_python_DEPENDS"
+    EXPORT_PROPERTIES "mlir_python_SOURCES_TYPE;mlir_python_ROOT_DIR;mlir_python_DEST_PREFIX;mlir_python_SOURCES;mlir_python_DEPENDS"
     mlir_python_SOURCES_TYPE pure
     mlir_python_ROOT_DIR "${ARG_ROOT_DIR}"
     mlir_python_DEST_PREFIX "${ARG_DEST_PREFIX}"
     mlir_python_SOURCES "${ARG_SOURCES}"
     mlir_python_FILE_DEPENDS "${_file_depends}"
     mlir_python_DEPENDS ""
   )
   # Note that an "include" directory has no meaning to such faux targets,
   # but it is a CMake supported way to specify a directory search list in a
   # way that works both in-tree and out. It has some super powers which are
   # not possible to emulate with custom properties (because of the prohibition
   # on using generator expressions in exported custom properties and the
   # special dispensation for $<INSTALL_PREFIX>).
   target_include_directories(${name} INTERFACE
     "$<BUILD_INTERFACE:${ARG_ROOT_DIR}>"
     "$<INSTALL_INTERFACE:${_install_destination}>"
   )
 
   # Add to parent.
   if(ARG_ADD_TO_PARENT)
     set_property(TARGET ${ARG_ADD_TO_PARENT} APPEND PROPERTY mlir_python_DEPENDS ${name})
   endif()
+  set_property(GLOBAL APPEND PROPERTY MLIR_EXPORTS ${name})
 
   # Install.
   if(NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
     _mlir_python_install_sources(
       ${name} "${ARG_ROOT_DIR}" "${_install_destination}"
       ${ARG_SOURCES}
     )
   endif()
function(declare_mlir_python_extension name)
   set(_install_destination "src/python/${name}")
 
   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
     # Note that ROOT_DIR and FILE_DEPENDS are not exported because they are
     # only relevant to in-tree uses.
-    EXPORT_PROPERTIES "mlir_python_SOURCES_TYPE;mlir_python_EXTENSION_MODULE_NAME;mlir_python_CPP_SOURCES;mlir_python_PRIVATE_LINK_LIBS;mlir_python_EMBED_CAPI_LINK_LIBS;mlir_python_DEPENDS"
+    EXPORT_PROPERTIES "mlir_python_SOURCES_TYPE;mlir_python_ROOT_DIR;mlir_python_EXTENSION_MODULE_NAME;mlir_python_CPP_SOURCES;mlir_python_PRIVATE_LINK_LIBS;mlir_python_EMBED_CAPI_LINK_LIBS;mlir_python_DEPENDS"
     mlir_python_SOURCES_TYPE extension
     mlir_python_ROOT_DIR "${ARG_ROOT_DIR}"
     mlir_python_EXTENSION_MODULE_NAME "${ARG_MODULE_NAME}"
     mlir_python_CPP_SOURCES "${ARG_SOURCES}"
     mlir_python_PRIVATE_LINK_LIBS "${ARG_PRIVATE_LINK_LIBS}"
     mlir_python_EMBED_CAPI_LINK_LIBS "${ARG_EMBED_CAPI_LINK_LIBS}"
     mlir_python_FILE_DEPENDS ""
     mlir_python_DEPENDS ""
target_include_directories(${name} INTERFACE
     "$<INSTALL_INTERFACE:${_install_destination}>"
   )
 
   # Add to parent.
   if(ARG_ADD_TO_PARENT)
     set_property(TARGET ${ARG_ADD_TO_PARENT} APPEND PROPERTY mlir_python_DEPENDS ${name})
   endif()
 
+  set_property(GLOBAL APPEND PROPERTY MLIR_EXPORTS ${name})
   # Install.
   if(NOT LLVM_INSTALL_TOOLCHAIN_ONLY)
     _mlir_python_install_sources(
       ${name} "${ARG_ROOT_DIR}" "src/python/${name}"
       ${ARG_SOURCES}
     )
   endif()
 endfunction()
function(add_mlir_python_modules name)
   cmake_parse_arguments(ARG
     ""
     "ROOT_PREFIX;INSTALL_PREFIX;COMMON_CAPI_LINK_LIBS"
     "DECLARED_SOURCES"
     ${ARGN})
   # Helper to process an individual target.
   function(_process_target modules_target sources_target)
     get_target_property(_source_type ${sources_target} mlir_python_SOURCES_TYPE)
-
-    # The root directory differs based on whether it is IMPORTED (installed
-    # dep).
-    get_target_property(_is_imported ${sources_target} IMPORTED)
-    if(NOT _is_imported)
-      # In-tree.
-      get_target_property(_python_root_dir ${sources_target} mlir_python_ROOT_DIR)
-    else()
-      # Imported.
-      # Note: We only populate a single directory in
-      # INTERFACE_INCLUDE_DIRECTORIES, so we can get away with just using it
-      # as a single value.
-      get_target_property(_python_root_dir ${sources_target} INTERFACE_INCLUDE_DIRECTORIES)
+    if(NOT _python_root_dir)
+      message(FATAL_ERROR " Target ${sources_target} lacks mlir_python_ROOT_DIR property")
     endif()
 
     if(_source_type STREQUAL "pure")
       # Pure python sources to link into the tree.
       get_target_property(_python_sources ${sources_target} mlir_python_SOURCES)
       get_target_property(_specified_dest_prefix ${sources_target} mlir_python_DEST_PREFIX)
       foreach(_source_relative_path ${_python_sources})
         set(_dest_relative_path "${_source_relative_path}")

mlir/examples/standalone/test/python/smoketest.py

 # RUN: %PYTHON %s | FileCheck %s
 
 from mlir_standalone.ir import *
 from mlir_standalone.dialects import (
   builtin as builtin_d,
   standalone as standalone_d
 )
 
 with Context():
   standalone_d.register_dialect()
   module = Module.parse("""
-    %0 = constant 2 : i32
+    %0 = arith.constant 2 : i32
     %1 = standalone.foo %0 : i32
     """)
-  # CHECK: %[[C:.*]] = constant 2 : i32
+  # CHECK: %[[C:.*]] = arith.constant 2 : i32
   # CHECK: standalone.foo %[[C]] : i32
   print(str(module))

mlir/test/Examples/standalone/test.toy

 # RUN: %cmake %mlir_src_root/examples/standalone -DCMAKE_CXX_COMPILER=%host_cxx -DCMAKE_C_COMPILER=%host_cc -DLLVM_ENABLE_LIBCXX=%enable_libcxx -DMLIR_DIR=%mlir_cmake_dir ; %cmake --build . --target check-standalone | tee %t | FileCheck %s
 
-# CHECK: Passed: 4
+# CHECK: Passed: 5
 # UNSUPPORTED: windows, android