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

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,13 @@
+# RUN: not llc -run-pass=none -o - %s 2>&1 | FileCheck %s --check-prefix=ERR
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arsenm wrote:

```suggestion
# RUN: not llc -run-pass=none -filetype=null %s 2>&1 | FileCheck %s --check-prefix=ERR
```

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