[llvm] [MIR] Serialize virtual register flags (PR #110228)

[Matt Arsenault via llvm-commits]

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@@ -47,6 +47,7 @@ struct VRegInfo {
   } D;
   Register VReg;
   Register PreferredReg;
+  std::vector<::uint8_t> Flags;
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arsenm wrote:

Why is the :: needed

https://github.com/llvm/llvm-project/pull/110228