[clang] Add time trace scopes to addToCallGraph & getCFG (PR #174717)

[Gábor Horváth via cfe-commits]

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@@ -61,6 +62,7 @@ class CallGraph : public DynamicRecursiveASTVisitor {
   ///
   /// Recursively walks the declaration to find all the dependent Decls as well.
   void addToCallGraph(Decl *D) {
+    llvm::TimeTraceScope TimeProfile("AddToCallGraph");
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Xazax-hun wrote:

I see. In case we have these patterns elsewhere as well, I am fine with this. 

>  the profiles would still be correct (if that is your concern).

My main concern is about the profiles being less precise, and having more overhead. 

https://github.com/llvm/llvm-project/pull/174717