[clang] [clang-tools-extra] [clang analysis] ExprMutationAnalyzer avoid infinite recursion for recursive forwarding reference (PR #87954)

[Piotr Zegar via cfe-commits]

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@@ -22,8 +21,15 @@ class FunctionParmMutationAnalyzer;
 /// a given statement.
 class ExprMutationAnalyzer {
 public:
+  friend class FunctionParmMutationAnalyzer;
+  struct Cache {
+    llvm::DenseMap<const FunctionDecl *,
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PiotrZSL wrote:

Note: consider using llvm::SmallDenseMap, to reduce amount of memory allocations.

https://github.com/llvm/llvm-project/pull/87954