[llvm] [CodeGen] Port FreeMachineFunction to new pass manager (PR #79421)

[Matt Arsenault via llvm-commits]

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@@ -125,8 +125,8 @@ MACHINE_FUNCTION_ANALYSIS("pass-instrumentation", PassInstrumentationAnalysis,
 #ifndef MACHINE_FUNCTION_PASS
 #define MACHINE_FUNCTION_PASS(NAME, PASS_NAME, CONSTRUCTOR)
 #endif
+MACHINE_FUNCTION_PASS("free-machine-function", FreeMachineFunctionPass, ())
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arsenm wrote:

do we somehow block running this with -run-pass? What happens if you manually run this on its own or before other passes?

https://github.com/llvm/llvm-project/pull/79421