llvm dev - Dec 2018 - Difficulty in understanding loop analysis code

Hey all!
I'm new to LLVM and advance C++.
 I came across this piece of code and found it difficult to understand.

Can anyone please explain how is it working ? I want to get loop count, sub loop
count etc printed as output.Thanks.
//Iteration on loops            for (LoopInfo::iterator i = LI.begin(), e =
LI.end(); i != e; ++i)
            {
                Loop *L = *i;
                int subloop = 1;
                countLoop++;
                
                static LLVMContext Context;
                BasicBlock *parentLoopPred = L->getLoopPredecessor();
                BasicBlock *parentLoopHead = L->getHeader();
                std::vector<Loop*> subLoopAll = L->getSubLoops();
                                
                Loop::iterator j, f;
                //Parent Loop Calculation
                //Counter = 0 instruction insertion
                // You must declare a constant Int like so instead of using it
directly in a AllocaInst instantiation.
                ConstantInt *IntVal4 =
ConstantInt::get(Type::getInt32Ty(Context), 4); // counter = 4
                Value *one1 = ConstantInt::get(Type::getInt32Ty(Context), -1,
true);
                Instruction *ACounter1 = new
AllocaInst(Type::getInt32Ty(Context), 0, IntVal4, "counter"); 
//(IntegerType::get(mContext, 32), one,    "counter",
loopPredecessor);  //(IntegerType::get(mContext, 32), IR.getInt32(0),
"counter");
              
 parentLoopPred->getInstList().insert(parentLoopPred->getFirstInsertionPt(),
ACounter1);

                Instruction *SCounter1 = new StoreInst(one1, ACounter1);
                SCounter1->insertAfter(ACounter1);
                //Counter++ instruction insertion
                Value *IValue1 = ConstantInt::get(Type::getInt32Ty(Context), 1,
true);
                Instruction *CValue1 = new LoadInst(ACounter1,
"midCount");
              
 parentLoopHead->getInstList().insert(parentLoopHead->getFirstInsertionPt(),
CValue1);
                Instruction *NValue1 = BinaryOperator::CreateNSWAdd(CValue1,
IValue1, "incremented");//  Instruction::Add, CValue, IValue,
"");
                NValue1->insertAfter(CValue1);
                Instruction *SNValue1 = new StoreInst(NValue1, ACounter1);
                SNValue1->insertAfter(NValue1);
                Value *PValue1 = SNValue1->getOperand(0);
                std::vector<Value *> printArrayRef1;
                Value *PValue12 = ConstantInt::get(Type::getInt32Ty(Context),
subLoopAll.size(), true);
                std::vector<Value *> printArrayRef12;
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