Chapter 9, Working with PassManager and AnalysisManager

1. In the StrictOpt example in the Writing a LLVM Pass for the new PassManager section, how do we write a Pass without deriving the PassInfoMixin class?
   • The PassInfoMixin class only defines a utility function for you, name, which returns the name of this Pass. Therefore, you can easily create one by yourself. Here is an example:

     struct MyPass {
       static StringRef name() { return "MyPass"; }
       PreservedAnalyses run(Function&, FunctionAnalysisManager&);
     };

2. How do we develop custom instrumentation for the new PassManager? How do we do it without modifying the LLVM source tree? (Hint: Use the Pass plugin we learned in this chapter.)
   • Pass instrumentation is a piece of code that runs before and/or after an LLVM Pass. This blog post shows an example of developing a custom Pass instrumentation via the Pass plugin: https://medium.com/@mshockwave/writing-pass-instrument-for-llvm-newpm-f17c57d3369f...