#include "llvm/IR/Function.h"
#include "llvm/Pass.h"
#include "llvm/Support/raw_ostream.h"

using namespace llvm;

namespace {

  struct OpcodeCounter : public FunctionPass {
    static char ID; // Pass identification, replacement for typeid
    OpcodeCounter() : FunctionPass(ID) {}

    bool runOnFunction(Function &F) override {
        std::map<std::string, int> opcode_map;
        errs() << "Function name: ";
        errs() << F.getName() << '\n';
        for(Function::iterator bb = F.begin(), e = F.end(); bb!=e; bb++)
        {
            for(BasicBlock::iterator i = bb->begin(), i2 = bb->end(); i!=i2; i++)
            {
                if(opcode_map.find(i->getOpcodeName()) == opcode_map.end())
                    opcode_map[i->getOpcodeName()] = 1;
                else
                    opcode_map[i->getOpcodeName()] += 1;
            }
        }

        std::map<std::string, int> :: iterator p_start = opcode_map.begin();
        std::map<std::string, int> :: iterator p_final = opcode_map.end();
        while(p_start != p_final)
        {
            outs()<< p_start->first << " ::: " << p_start->second <<"\n";
            p_start++;
        }

        opcode_map.clear();
        return false;
    }
  };
}

char OpcodeCounter::ID = 0;
static RegisterPass<OpcodeCounter> X("OpcodeCounter", "Count the number of opcode for every type");

参考https://blog.csdn.net/baimafujinji/article/category/7313378