[MLIR] Fix checks for native arch

[nikic]

Summary

Using if (TARGET ${LLVM_NATIVE_ARCH}) only works if MLIR is built together with LLVM, but not for standalone builds of MLIR. The correct way to check this is if (${LLVM_NATIVE_ARCH} IN_LIST LLVM_TARGETS_TO_BUILD), as the LLVM build system exports LLVM_TARGETS_TO_BUILD.

[nikic]

Add a MLIR_ENABLE_EXECUTION_ENGINE variable to avoid repeating the same check and comment everywhere.

mlir/CMakeLists.txt

 add_custom_target(mlir-generic-headers)
 set_target_properties(mlir-generic-headers PROPERTIES FOLDER "Misc")
 # mlir-headers may be dialect-dependent.
 add_custom_target(mlir-headers)
 set_target_properties(mlir-headers PROPERTIES FOLDER "Misc")
 add_dependencies(mlir-headers mlir-generic-headers)
 add_custom_target(mlir-doc)
 
+# Only enable execution engine if the native target is available.
+if(${LLVM_NATIVE_ARCH} IN_LIST LLVM_TARGETS_TO_BUILD)
+  set(MLIR_ENABLE_EXECUTION_ENGINE 1)
+else()
+  set(MLIR_ENABLE_EXECUTION_ENGINE 0)
+endif()
+
 # Build the CUDA conversions and run according tests if the NVPTX backend
 # is available
-if ("NVPTX" IN_LIST LLVM_TARGETS_TO_BUILD)
+if ("NVPTX" IN_LIST LLVM_TARGETS_TO_BUILD AND MLIR_ENABLE_EXECUTION_ENGINE)
   set(MLIR_ENABLE_CUDA_CONVERSIONS 1)
 else()
   set(MLIR_ENABLE_CUDA_CONVERSIONS 0)
 endif()
 # TODO: we should use a config.h file like LLVM does
 add_definitions(-DMLIR_CUDA_CONVERSIONS_ENABLED=${MLIR_ENABLE_CUDA_CONVERSIONS})
 
 # Build the ROCm conversions and run according tests if the AMDGPU backend
-# is available
-if ("AMDGPU" IN_LIST LLVM_TARGETS_TO_BUILD)
+# is available.
+if ("AMDGPU" IN_LIST LLVM_TARGETS_TO_BUILD AND MLIR_ENABLE_EXECUTION_ENGINE)
   set(MLIR_ENABLE_ROCM_CONVERSIONS 1)
 else()
   set(MLIR_ENABLE_ROCM_CONVERSIONS 0)
 endif()
 add_definitions(-DMLIR_ROCM_CONVERSIONS_ENABLED=${MLIR_ENABLE_ROCM_CONVERSIONS})
 
 set(MLIR_ENABLE_CUDA_RUNNER 0 CACHE BOOL "Enable building the mlir CUDA runner")
 set(MLIR_ENABLE_ROCM_RUNNER 0 CACHE BOOL "Enable building the mlir ROCm runner")

mlir/lib/CAPI/CMakeLists.txt

 add_subdirectory(Debug)
 add_subdirectory(Dialect)
 add_subdirectory(Conversion)
 add_subdirectory(Interfaces)
 add_subdirectory(IR)
 add_subdirectory(RegisterEverything)
 add_subdirectory(Transforms)
 
-# Only enable the ExecutionEngine if the native target is configured in.
-if(TARGET ${LLVM_NATIVE_ARCH})
+if(MLIR_ENABLE_EXECUTION_ENGINE)
   add_subdirectory(ExecutionEngine)
 endif()
 
 # Build the optional CAPI dylib.
 if(MLIR_BUILD_MLIR_C_DYLIB)
   message(STATUS "Building MLIR-C dylib")
   get_property(_capi_libraries GLOBAL PROPERTY MLIR_CAPI_LIBRARIES)
   add_mlir_aggregate(MLIR-C

mlir/lib/ExecutionEngine/CMakeLists.txt

add_mlir_library(MLIRExecutionEngineUtils
   InstCombine
   ScalarOpts
   Vectorize
   TransformUtils
   IPO
   Passes
   )
 
-# Only enable the ExecutionEngine if the native target is configured in.
-if(NOT TARGET ${LLVM_NATIVE_ARCH})
+if(NOT MLIR_ENABLE_EXECUTION_ENGINE)
   return()
 endif()
 
 if(LLVM_USE_INTEL_JITEVENTS)
   set(LLVM_JIT_LISTENER_LIB
       IntelJITEvents)
 endif(LLVM_USE_INTEL_JITEVENTS)
 

mlir/python/CMakeLists.txt

declare_mlir_python_extension(MLIRPythonExtension.AsyncDialectPasses
   SOURCES
     AsyncPasses.cpp
   PRIVATE_LINK_LIBS
     LLVMSupport
   EMBED_CAPI_LINK_LIBS
     MLIRCAPIAsync
 )
 
-# Only enable the ExecutionEngine if the native target is configured in.
-if(TARGET ${LLVM_NATIVE_ARCH})
+if(MLIR_ENABLE_EXECUTION_ENGINE)
   declare_mlir_python_extension(MLIRPythonExtension.ExecutionEngine
     MODULE_NAME _mlirExecutionEngine
     ADD_TO_PARENT MLIRPythonSources.ExecutionEngine
     ROOT_DIR "${PYTHON_SOURCE_DIR}"
     SOURCES
       ExecutionEngineModule.cpp
     PRIVATE_LINK_LIBS
       LLVMSupport

mlir/test/CAPI/CMakeLists.txt

if(MLIR_BUILD_MLIR_C_DYLIB)
     target_link_libraries(${name} PRIVATE
       MLIR-C)
   else()
     target_link_libraries(${name} PRIVATE
       ${ARG_LINK_LIBS})
   endif()
 endfunction(_add_capi_test_executable)
 
-# Only enable the ExecutionEngine if the native target is configured in.
-if(TARGET ${LLVM_NATIVE_ARCH})
+if(MLIR_ENABLE_EXECUTION_ENGINE)
   _add_capi_test_executable(mlir-capi-execution-engine-test
     execution_engine.c
   LINK_LIBS PRIVATE
     MLIRCAPIConversion
     MLIRCAPIExecutionEngine
     MLIRCAPIRegisterEverything
 )
 endif()

mlir/test/CMakeLists.txt

if (MLIR_INCLUDE_INTEGRATION_TESTS)
   option(MLIR_RUN_X86VECTOR_TESTS "Run X86Vector tests.")
   option(MLIR_RUN_CUDA_TENSOR_CORE_TESTS "Run CUDA Tensor core WMMA tests.")
   option(MLIR_RUN_ARM_SVE_TESTS "Run Arm SVE tests.")
   # Passed to lit.site.cfg.py.in to set up the path where to find the libraries.
   set(MLIR_INTEGRATION_TEST_DIR ${CMAKE_LIBRARY_OUTPUT_DIRECTORY})
 
 
   # The native target may not be enabled when cross compiling, raise an error.
-  if(NOT TARGET ${LLVM_NATIVE_ARCH})
+  if(NOT MLIR_ENABLE_EXECUTION_ENGINE)
     message(FATAL_ERROR "MLIR_INCLUDE_INTEGRATION_TESTS requires a native target")
   endif()
 
   # Copy test data over.
   file(COPY ${CMAKE_CURRENT_SOURCE_DIR}/Integration/data/mttkrp_b.tns
             ${CMAKE_CURRENT_SOURCE_DIR}/Integration/data/test.mtx
             ${CMAKE_CURRENT_SOURCE_DIR}/Integration/data/test_symmetric.mtx
             ${CMAKE_CURRENT_SOURCE_DIR}/Integration/data/test_symmetric_complex.mtx

mlir/tools/CMakeLists.txt

 add_subdirectory(mlir-lsp-server)
 add_subdirectory(mlir-opt)
 add_subdirectory(mlir-parser-fuzzer)
 add_subdirectory(mlir-pdll-lsp-server)
 add_subdirectory(mlir-reduce)
 add_subdirectory(mlir-shlib)
 add_subdirectory(mlir-spirv-cpu-runner)
 add_subdirectory(mlir-translate)
 add_subdirectory(mlir-vulkan-runner)
 add_subdirectory(tblgen-lsp-server)
 
-# mlir-cpu-runner requires ExecutionEngine which is only built
-# when the native target is configured in.
-if(TARGET ${LLVM_NATIVE_ARCH})
+# mlir-cpu-runner requires ExecutionEngine.
+if(MLIR_ENABLE_EXECUTION_ENGINE)
   add_subdirectory(mlir-cpu-runner)
 endif()

mlir/unittests/CMakeLists.txt

 add_subdirectory(IR)
 add_subdirectory(Parser)
 add_subdirectory(Pass)
 add_subdirectory(Support)
 add_subdirectory(Rewrite)
 add_subdirectory(TableGen)
 add_subdirectory(Transforms)
 
-# The native target may not be enabled when cross compiling.
-if(TARGET ${LLVM_NATIVE_ARCH})
+if(MLIR_ENABLE_EXECUTION_ENGINE)
   add_subdirectory(ExecutionEngine)
 endif()