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The fastest smart pointer in the west

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7 Oct 200313 min read 111.8K   1.6K   41  
Need a super quick implementation of a reference counting smart pointer? AUTO_REF delivers just that, with a 'thin' source code of just 3,886 bytes (< 4KB)
// e_ver.cpp : Defines the entry point for the console application.
//
// Objective: simulate an algorithm which uses pointers for benchmarking puposes
//


#pragma warning(disable:4786) 



#include "setup.h"





//=====================================================================
//=====================================================================
//=====================================================================

#include <cassert>
#include <windows.h>
#include <vector>
#include <iostream>

#include "auto_ref.h"
#include "other/SmartPtr_a.h"
#include "other/SmartPtr_b.h"
// #include "other/SmartPtr_c.h"
#include <boost/smart_ptr.hpp>



using std::cout;
using std::endl;
using std::dec;












//=====================================================================
//=====================================================================
//=====================================================================









class MY_CLASS
{
public:
   

#if PTR_SWITCH == 40
   typedef AUTO_REF<MY_CLASS> MY_PTR;  //A
#elif PTR_SWITCH == 50
   typedef MY_CLASS *MY_PTR;  //B
#elif PTR_SWITCH == 60
   typedef RefCountPtr<MY_CLASS> MY_PTR; //C
#elif PTR_SWITCH == 70
   typedef idllib::SmartPtr<MY_CLASS> MY_PTR;  //D
#elif PTR_SWITCH == 80
   typedef boost::shared_ptr<MY_CLASS> MY_PTR;  //E
#elif PTR_SWITCH == 90
   typedef GE::Safe::PtrStrong<MY_CLASS> MY_PTR;  //E
#else
#  error illegal PTR_SWITCH value

#endif //PTR_SWITCH



private:
   int m_int_val;
   bool is_set_b;
   MY_PTR m_friend_p;


public:
   MY_CLASS(int int_val = 0) : m_int_val(int_val), is_set_b(false) {}
   ~MY_CLASS() {
#ifdef VERBOSE
      cout << "shutdown of [ " << dec << m_int_val << "]" << endl;
#endif
   }

   void show()  {
      if (is_set_b)
         cout << " me: " << m_int_val << " -> " << m_friend_p->m_int_val
            << "(frnd) "<< endl;
      else
         cout << " me: " << m_int_val << " -> " << "(no frnd) " 
            << endl;
   }

   int get_val() {
      return m_int_val;
   }

   void set_friend(const MY_PTR &x) {
      is_set_b = true;
      m_friend_p = x;
   }

   int get_friend_val()  {
      if(is_set_b)
         return m_friend_p->get_val();
      
      return -1;
   }
};





//=====================================================================
//=====================================================================
//=====================================================================



typedef MY_CLASS::MY_PTR MY_PTR;
typedef std::vector<MY_PTR> my_vec_t;



#ifdef VERBOSE
enum { 
   LIMIT = 20 
};
#else
enum { 
   LIMIT = 320000 
};
#endif



//=====================================================================
//=====================================================================
//=====================================================================


inline MY_PTR &get_at(my_vec_t *vec_p, int index) {
   return (*vec_p)[index];
}

void print_all(my_vec_t &vec) {
   for (my_vec_t::size_type i = 0 ; i < vec.size(); ++i)
      get_at(&vec, i)->show();
}



#if PTR_SWITCH == 50
void delete_objects(my_vec_t &vec) {
   my_vec_t::iterator last(vec.end());
   for (my_vec_t::iterator i = vec.begin() ; i != last ; ++i) 
      delete (*i);
}
#endif

void fill(my_vec_t **vec_pp, int limit) {

   *vec_pp = new my_vec_t;

   for (int i = 0 ; i < limit ; ++i)
      (*vec_pp)->push_back( MY_PTR(new MY_CLASS(10000+i)) );
}



//=====================================================================
//=====================================================================
//=====================================================================



void main_p()
{


   my_vec_t *vec_p;

   fill(&vec_p, LIMIT);



#ifdef VERBOSE
   print_all(*vec_p);
#endif
   for (int i = 0 ; i < LIMIT * 2 ; i++)
   {
      int x = rand() % ((LIMIT-2)/2);

      int y = LIMIT/2 + rand() % ((LIMIT-2)/2);

#ifdef VERBOSE
      cout << x <<  " -> " << y << endl;
#endif

      get_at(vec_p, x)->set_friend( get_at(vec_p, y));

   }

   int s = 0;
   for (i = 0 ; i < LIMIT * 60 ; i++) {
      int x = rand() % LIMIT;
      int l = get_at(vec_p, x)->get_friend_val();
      s += l;
   }

#ifdef VERBOSE
   print_all(*vec_p);
#endif

#if PTR_SWITCH == 50
   delete_objects(*vec_p);
#endif
   delete vec_p;

} //main_p()






//=====================================================================
//=====================================================================
//=====================================================================


void check_mem()
{
   std::vector<void*> ptrs;
   
   int limit = 20;
   for(int i = 0; i < limit; ++i)
      ptrs.push_back(g_the_auto_ref_pool.malloc());

   int sz = ptrs.size();      
   while(sz > 0)
   {
      int pos = rand() % sz;
      g_the_auto_ref_pool.free(ptrs[pos]);
      std::swap(ptrs[pos], ptrs[sz - 1]);
      
      sz -= 1;
   }      
   
   for(i = 0; i < limit; ++i)
   {
      void* temp = g_the_auto_ref_pool.malloc();
      assert(temp == ptrs[i]);
   } 
}

int main(int argc, char* argv[]) 
{   
   check_mem();
   
   DWORD t0 = GetTickCount();

   main_p();


   DWORD t1 = GetTickCount();



#if 1
   cout << "run time = " << (t1-t0)/1000.0 << endl;
#endif

   cout << "main is done!" << endl;
	return 0;
}


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