[llvm] [NFC] Move DroppedVariableStats to its own file and redesign it to be extensible. (PR #115563)

[Adrian Prantl via llvm-commits]

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@@ -1,4 +1,4 @@
-//===- unittests/IR/DroppedVariableStatsTest.cpp - TimePassesHandler tests
+//===- unittests/IR/DroppedVariableStatsIRTest.cpp - TimePassesHandler tests
 //----------===//
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adrian-prantl wrote:

going above 80 Colm limit here

https://github.com/llvm/llvm-project/pull/115563