[llvm] Add the 'initialized' attribute langref and support (PR #84803)

[Jan Voung via llvm-commits]

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@@ -38,6 +38,9 @@ class IntAttr<string S, list<AttrProperty> P> : Attr<S, P>;
 /// Type attribute.
 class TypeAttr<string S, list<AttrProperty> P> : Attr<S, P>;
 
+/// Const range list attribute.
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jvoung wrote:

nit: put closer to the ConstantRangeAttr?


https://github.com/llvm/llvm-project/pull/84803