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

[Matt Arsenault via llvm-commits]

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@@ -683,6 +683,15 @@ bool MIRParserImpl::parseRegisterInfo(PerFunctionMIParsingState &PFS,
                                  VReg.PreferredRegister.Value, Error))
         return error(Error, VReg.PreferredRegister.SourceRange);
     }
+
+    for(const auto &FlagStringValue: VReg.RegisterFlags) {
+      uint8_t FlagValue;
+      if(Target->getVRegFlagValue(FlagStringValue.Value, FlagValue))
+        return error(FlagStringValue.SourceRange.Start,
+                      Twine("use of undefined register flag '") +
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arsenm wrote:

Missing error test? 

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