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

[Matt Arsenault via llvm-commits]

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@@ -3412,6 +3412,9 @@ void Attributor::identifyDefaultAbstractAttributes(Function &F) {
     // Every function can track active assumptions.
     getOrCreateAAFor<AAAssumptionInfo>(FPos);
 
+    // Every function can have out arguments.
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arsenm wrote:

Only functions with pointer arguments, not sure if it's worth checking if there are any 

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