[llvm] [NewPM][CodeGen] Let `ModuleToMachineFunctionPassAdaptor` own `MachineModuleInfo` (PR #87226)

[Christudasan Devadasan via llvm-commits]

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@@ -106,6 +107,8 @@ class PassBuilder {
   PipelineTuningOptions PTO;
   std::optional<PGOOptions> PGOOpt;
   PassInstrumentationCallbacks *PIC;
+  std::unique_ptr<MachineModuleInfo> MMI;
+  MachineModuleInfo *MMIRefPtr; // As reference to MMI
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cdevadas wrote:

Can you explain why this design choice to use a unique_ptr and its reference?

https://github.com/llvm/llvm-project/pull/87226