Revert "[InlineAdvisor] Restructure advisor plugin unittest cmake"

This reverts commit f29cfab55d.

llvm/unittests/Analysis/CMakeLists.txt

@@ -52,6 +52,11 @@ set(ANALYSIS_TEST_SOURCES
   VectorUtilsTest.cpp
   )
 
+# The unit tests target does not use InlineAdvisorPlugin.cpp
+# so if not added to LLVM_OPTIONAL_SOURCES, FileCheck will
+# complain about unused file.
+set(LLVM_OPTIONAL_SOURCES InlineAdvisorPlugin.cpp)
+
 set(MLGO_TESTS TFUtilsTest.cpp TrainingLoggerTest.cpp)
 if (LLVM_HAVE_TFLITE)
   LIST(APPEND ANALYSIS_TEST_SOURCES ${MLGO_TESTS})
@@ -65,4 +70,35 @@ add_llvm_unittest_with_input_files(AnalysisTests
 
 target_link_libraries(AnalysisTests PRIVATE LLVMTestingSupport)
 
-add_subdirectory(InlineAdvisorPlugin)
+# The advisor plugin expects to not link against the Analysis, Support and Core 
+# libraries, but expects them to exist in the process loading the plugin. This 
+# doesn't work with DLLs on Windows (where a shared library can't have undefined
+# references), so just skip this testcase on Windows.
+if (NOT WIN32)
+  # On AIX, enable run-time linking to allow symbols from the plugins shared
+  # objects to be properly bound.
+  if(CMAKE_SYSTEM_NAME STREQUAL "AIX")
+    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-brtl")
+  endif()
+
+  # This plugin is built as a stand-alone plugin, so since we don't use the
+  # ANALYSIS_TEST_SOURCES files, we have to add them to LLVM_OPTIONAL_SOURCES
+  # so that FileCheck doesn't complain about unsued files.
+  LIST(APPEND LLVM_OPTIONAL_SOURCES ${ANALYSIS_TEST_SOURCES})
+
+  unset(LLVM_LINK_COMPONENTS)
+  add_llvm_library(InlineAdvisorPlugin MODULE BUILDTREE_ONLY InlineAdvisorPlugin.cpp)
+  # Put PLUGIN next to the unit test executable.
+  set_output_directory(InlineAdvisorPlugin
+      BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}
+      LIBRARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}
+      )
+  set_target_properties(InlineAdvisorPlugin PROPERTIES FOLDER "Tests")
+
+  export_executable_symbols_for_plugins(AnalysisTests)
+  # The plugin depends on some of the output files of intrinsics_gen, so make sure
+  # it is built before the plugin.
+  add_dependencies(InlineAdvisorPlugin intrinsics_gen)
+  add_dependencies(AnalysisTests InlineAdvisorPlugin)
+  set_property(TARGET InlineAdvisorPlugin PROPERTY FOLDER "Tests/UnitTests/AnalysisTests")
+endif()