[llvm] [ArgPromotion] Handle pointer arguments of recursive calls (PR #78735)

[Matt Arsenault via llvm-commits]

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@@ -610,13 +610,78 @@ static bool findArgParts(Argument *Arg, const DataLayout &DL, AAResults &AAR,
       // unknown users
     }
 
+    auto *CB = dyn_cast<CallBase>(V);
+    Value *PtrArg = dyn_cast<Value>(U);
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arsenm wrote:

Why do you need to dyn_cast to Value? 

https://github.com/llvm/llvm-project/pull/78735