Clang as a preprocessor

I want to change (add) the arguments passed to a function. For example, if I have the call:


I will need to add other parameters for example c and n1, and the result should be:


I think that I must do it with the function:

bool MyRecursiveASTVisitor::VisitCallExpr(CallExpr *CE)

but i don’t know how to implement it. Can you help me with this please?

thank very much for your attention.