[llvm] [llvm][TableGen] Add a !initialized predicate to allow testing for ? (PR #117964)

[Akshat Oke via llvm-commits]

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@@ -917,6 +917,13 @@ const Init *UnOpInit::Fold(const Record *CurRec, bool IsFinal) const {
       return NewInit;
     break;
 
+  case INITIALIZED:
+    if (isa_and_nonnull<UnsetInit>(LHS))
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optimisan wrote:

This choice seems interesting - `LHS` shouldn't ever be null here, right?

https://github.com/llvm/llvm-project/pull/117964