[llvm] [CodeGen] Expose the extensibility of PassConfig to plugins (PR #139059)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,16 @@
+if (NOT WIN32 AND NOT CYGWIN)
+	unset(LLVM_LINK_COMPONENTS)
+	add_llvm_library(CGTestPlugin MODULE BUILDTREE_ONLY
+			CodeGenTestPass.cpp
+			Plugin.cpp
+	)
+
+	# Put PLUGIN next to the unit test executable.
+	set_output_directory(CGTestPlugin
+			BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/../
+			LIBRARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/../
+	)
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arsenm wrote:

Just let it be emitted to the default location? I don't see why you need this in a particular location, the tests should use an explicit path to the built output 

https://github.com/llvm/llvm-project/pull/139059