[clang] [analyzer] Enforce not making overly complicated symbols (PR #144327)

[Balázs Benics via cfe-commits]

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@@ -671,17 +779,33 @@ class SymbolVisitor {
   virtual bool VisitMemRegion(const MemRegion *) { return true; }
 };
 
+// Returns a pointer to T if T is a SymbolData, otherwise SymExpr.
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balazs-benics-sonarsource wrote:

Reworked the code, and dropped the `auto` type spec. This should be more readable now.

https://github.com/llvm/llvm-project/pull/144327