[llvm] [Instrumentation] Support MachineFunction in ChangeReporter (PR #80946)

[Arthur Eubanks via llvm-commits]

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@@ -362,6 +384,13 @@ void ChangeReporter<T>::saveIRBeforePass(Any IR, StringRef PassID,
       handleInitialIR(IR);
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aeubanks wrote:

should we be calling this on MIR?

https://github.com/llvm/llvm-project/pull/80946