[llvm] Reland "[NFC] Move DroppedVariableStats to its own file and redesign it to be extensible (#118546)" (PR #119048)

[Sergei Barannikov via llvm-commits]

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@@ -50,6 +50,7 @@ add_llvm_component_library(LLVMCodeGen
   DeadMachineInstructionElim.cpp
   DetectDeadLanes.cpp
   DFAPacketizer.cpp
+  DroppedVariableStats.cpp
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s-barannikov wrote:

I think the linking error occurs because this pass is in a CodeGen library that IR libraries do not (and should not) depend on.
Building with `-DBUILD_SHARED_LIBS=ON` passed to CMake should reproduce the issue.


https://github.com/llvm/llvm-project/pull/119048