This LoopNestPass-version LIR is currently identical to the LoopPass-version
LIR. The new added pass is added into PassRegistry as "loop-nest-idiom".
The LoopNest structure makes optimizations that insert runtime checks for the
nested loop more easy to apply. D104636 is an example of a use case to this
newly created pass.
Function *F = LN.getParent();
const auto *DL = &F->getModule()->getDataLayout();
OptimizationRemarkEmitter ORE(F);