Question

I want to ask is that can we use the information generated by existing passes into a new pass?
If yes, then how ?
For example -loops gives the natural loop information, so can we use this information into new pass by calling it.

Answer 1

You can mark a pass as depending on another pass by overriding getAnalysisUsage() in the depending pass, then access the instance of that pass by calling getAnalysis(). You can then invoke whatever methods you want on that instance to get information out of it.