[clang] Optimize -Wunsafe-buffer-usage. (PR #124554)

[via cfe-commits]

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@@ -79,21 +81,39 @@ static std::string getDREAncestorString(const DeclRefExpr *DRE,
 } // namespace
 #endif /* NDEBUG */
 
-namespace clang::ast_matchers {
+class CustomMatcher {
+public:
+  virtual bool matches(const DynTypedNode &DynNode, ASTContext &Ctx,
+                       const UnsafeBufferUsageHandler &Handler) = 0;
+  virtual ~CustomMatcher() = default;
+};
+
+struct MatchResult {
+public:
+  std::map<std::string, DynTypedNode>
+      Nodes; // DynTypedNode needed to store different types of Nodes, not
+             // necessarily sharing the same base.
+
+  template <typename T> const T *getNodeAs(StringRef ID) const {
+    auto It = Nodes.find(std::string(ID));
+    if (It == Nodes.end()) {
+      return nullptr;
+    }
+    return It->second.get<T>();
+  }
+};
+
 // A `RecursiveASTVisitor` that traverses all descendants of a given node "n"
 // except for those belonging to a different callable of "n".
 class MatchDescendantVisitor : public DynamicRecursiveASTVisitor {
 public:
   // Creates an AST visitor that matches `Matcher` on all
   // descendants of a given node "n" except for the ones
   // belonging to a different callable of "n".
-  MatchDescendantVisitor(const internal::DynTypedMatcher *Matcher,
-                         internal::ASTMatchFinder *Finder,
-                         internal::BoundNodesTreeBuilder *Builder,
-                         internal::ASTMatchFinder::BindKind Bind,
+  MatchDescendantVisitor(CustomMatcher &Matcher, bool BindAll,
                          const bool ignoreUnevaluatedContext)
-      : Matcher(Matcher), Finder(Finder), Builder(Builder), Bind(Bind),
-        Matches(false), ignoreUnevaluatedContext(ignoreUnevaluatedContext) {
+      : Matcher(&Matcher), BindAll(BindAll), Matches(false),
----------------
ivanaivanovska wrote:

Changed to FindAll.

https://github.com/llvm/llvm-project/pull/124554