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

[Craig Topper via llvm-commits]

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@@ -1213,6 +1213,15 @@ class TargetRegisterInfo : public MCRegisterInfo {
   virtual bool isNonallocatableRegisterCalleeSave(MCRegister Reg) const {
     return false;
   }
+
+  virtual std::pair<bool, uint8_t> getVRegFlagValue(StringRef Name) const {
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topperc wrote:

Could this return a std::optional?

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