[clang] Reapply "[Clang] Profile singly-resolved UnresolvedLookupExpr with the declaration" (PR #140680)

[Younan Zhang via cfe-commits]

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@@ -2189,8 +2189,14 @@ StmtProfiler::VisitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *S) {
 
 void StmtProfiler::VisitOverloadExpr(const OverloadExpr *S) {
   VisitExpr(S);
-  VisitNestedNameSpecifier(S->getQualifier());
-  VisitName(S->getName(), /*TreatAsDecl*/ true);
+  bool DescribingDependentVarTemplate =
+      S->getNumDecls() == 1 && isa<VarTemplateDecl>(*S->decls_begin());
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zyn0217 wrote:

Instead of OverloadExpr, I'm thinking if it would be better to invent a new Expr node to describe dependent cases (we use DeclRefExpr for non-dependent uses), just like ConceptSpecializationExpr.

https://github.com/llvm/llvm-project/pull/140680