[llvm] [Attributor] Pack out arguments into a struct (PR #119267)

[Matt Arsenault via llvm-commits]

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@@ -3510,6 +3511,12 @@ void Attributor::identifyDefaultAbstractAttributes(Function &F) {
       // Every argument with pointer type might be privatizable (or
       // promotable)
       getOrCreateAAFor<AAPrivatizablePtr>(ArgPos);
+
+      // Every function with pointer argument type can have out arguments.
+      if (!markedAsAAConvertArgument) {
+        getOrCreateAAFor<AAConvertOutArgument>(FPos);
+        markedAsAAConvertArgument = true;
+      }
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arsenm wrote:

Yes. I don't know how aggressive the filters here should try to be, but it could more specifically be there is at least one pointer argument that is writable 

https://github.com/llvm/llvm-project/pull/119267