Printing changes after "emit" in Clang CodeGen


I am trying to identify the changes introduced by different functions
in CodeGenFunction of Clang. For example, if I want to see what was
"emitted" by printing before and after a call to
emitOMPSimdRegion(CodeGenFunction &CGF, OMPLoopDirective &S,
PrePostActionTy){}, I was trying S.dump(). It did not show any
changes. Is there any
printing utility we can use to print changes introduced by different emissions?

Thank you