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

[Jan Voung via llvm-commits]

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@@ -1565,6 +1566,8 @@ class LLVMContextImpl {
   UniqueStringSaver Saver{Alloc};
   SpecificBumpPtrAllocator<ConstantRangeAttributeImpl>
       ConstantRangeAttributeAlloc;
+  SpecificBumpPtrAllocator<ConstantRangeListAttributeImpl>
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jvoung wrote:

It seems this isn't used anymore? Just using Alloc now?

Then the forward declaration of ConstantRangeListAttributeImpl above isn't needed.

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