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approach1.cpp

#include <iostream>
#include <sys/time.h>

typedef float v4sf __attribute__ ((vector_size(16)));


using namespace std;


class Config
{
public:
   ///////////////////// Class vars declaration /////////////////////////

   static float c_a[ 3 ];
   static float c_b[ 3 ];
   static float c_c[ 3 ];
   static float c_d[ 3 ];
   static float c_e[ 3 ];
   static float c_f[ 3 ];
   static float c_g[ 3 ];
   static float c_h[ 3 ];
   static float c_i[ 3 ];
   static float c_j[ 3 ];

};

Config configObj;

//Config configObj;

#define __CLASSNAME__ Config

//////////// Class vars initialization ////////
float __CLASSNAME__::c_a[ 3 ] = { 0, 0.02, 0.1 };
float __CLASSNAME__::c_b[ 3 ] = { 0, 0.2, 0.2 };
float __CLASSNAME__::c_c[ 3 ] = { 0, -65.0, -65.0 };
float __CLASSNAME__::c_d[ 3 ] = { 0, 8.0, 2.0 };
float __CLASSNAME__::c_e[ 3 ] = { 0, 1.0, 1.0 };
float __CLASSNAME__::c_f[ 3 ] = { 0, 0.9, 0.9 };
float __CLASSNAME__::c_g[ 3 ] = { 0, 0, 0 };
float __CLASSNAME__::c_h[ 3 ] = { 0, 1.0, 1.0 };
float __CLASSNAME__::c_i[ 3 ] = { 0, 0.8582, 0.8582 };
float __CLASSNAME__::c_j[ 3 ] = { 0, 0, 0 };

class Unit
{

public:

   ~Unit();
   Unit(int num_of_instances);
   void Update( int num );

   public:
   ///////////////////// Instance vars declaration ///////////////////////
   float * ip;
   float * in;
   float * v;
   float * u;
   float * gG;
   float * gN;
   float * PN;
   float * _gs;
   float * _ns;
   float * _vslow;
   float * _v0;
   float * _vOld;


};

Unit::Unit(int num_of_instances)
{

   //////////// InstanceScalarVars initialization /////////////

   ip = new float [num_of_instances];

   in = new float [num_of_instances];
   v = new float [num_of_instances];
   u = new float [num_of_instances];
   gG = new float [num_of_instances];

   gN = new float [num_of_instances];
   PN = new  float[num_of_instances];
   _gs = new float [num_of_instances];
   _ns = new float [num_of_instances];

   _vslow = new float [num_of_instances];
   _v0 = new float [num_of_instances];
   _vOld = new float [num_of_instances];


  //cout<<"Absolute address:"<<ip<<" "<<in<<" "<<v<<" "<<u<<" "<<gG<<" "<<gN<<endl;
}



Unit::~Unit()
{
   delete[] ip;
   delete[] in;
   delete[] v;
   delete[] u;
   delete[] gG;
   delete[] gN;
   delete[] PN;
   delete[] _gs;
   delete[] _ns;
   delete[] _vslow;
   delete[] _v0;
   delete[] _vOld;
}

double getCurrentTime(){
   struct timeval curr;
   struct timezone tz;
   gettimeofday(&curr, &tz);
   double tmp = static_cast<double>(curr.tv_sec) * static_cast<double>(1000000)
         + static_cast<double>(curr.tv_usec);
   return tmp*1e-6;
}

void Unit::Update(int num)
{
    v4sf var_0 = {configObj.c_e[1],configObj.c_e[1],configObj.c_e[1],configObj.c_e[1]};
    v4sf var_1 = {configObj.c_g[1],configObj.c_g[1],configObj.c_g[1],configObj.c_g[1]};
    v4sf var_2 = {80,80,80,80};
    v4sf var_3 = {configObj.c_j[1],configObj.c_j[1],configObj.c_j[1],configObj.c_j[1]};
    v4sf var_4 = {0.5,0.5,0.5,0.5};
    v4sf var_5 = {0.04,0.04,0.04,0.04};
    v4sf var_6 = {5,5,5,5};
    v4sf var_7 = {140,140,140,140};
    v4sf var_8 = {configObj.c_i[1],configObj.c_i[1],configObj.c_i[1],configObj.c_i[1]};
    v4sf var_9 = {configObj.c_a[1],configObj.c_a[1],configObj.c_a[1],configObj.c_a[1]};
    v4sf var_10 = {configObj.c_b[1],configObj.c_b[1],configObj.c_b[1],configObj.c_b[1]};
    v4sf var_11 = {configObj.c_f[1],configObj.c_f[1],configObj.c_f[1],configObj.c_f[1]};
    v4sf var_12 = {configObj.c_h[1],configObj.c_h[1],configObj.c_h[1],configObj.c_h[1]};
    v4sf var_13 = {0,0,0,0};
    v4sf var_14 = {0,0,0,0};


    for( int uidx = 0; uidx < num; uidx+=4 )
    {
        *(v4sf*)&_vOld[uidx] = *(v4sf*)&v[uidx];
        *(v4sf*)&gG[uidx] = *(v4sf*)&gG[uidx] + (var_0 * *(v4sf*)&in[uidx]);
        *(v4sf*)&gN[uidx] = *(v4sf*)&gN[uidx] + (var_1 * *(v4sf*)&ip[uidx]);
        *(v4sf*)&_gs[uidx] = *(v4sf*)&gG[uidx] * (*(v4sf*)&v[uidx] + var_2);
        *(v4sf*)&_ns[uidx] = *(v4sf*)&gN[uidx] * *(v4sf*)&v[uidx];
        *(v4sf*)&_vslow[uidx] = *(v4sf*)&v[uidx] - (*(v4sf*)&_ns[uidx] + *(v4sf*)&_gs[uidx]);
        *(v4sf*)&_v0[uidx] = *(v4sf*)&_vslow[uidx] + (var_3 * *(v4sf*)&PN[uidx]);
        *(v4sf*)&v[uidx] = *(v4sf*)&v[uidx] + var_4 * (((var_5 * *(v4sf*)&v[uidx] + var_6) * *(v4sf*)&v[uidx] + var_7) - (*(v4sf*)&u[uidx] - (var_8 * *(v4sf*)&ip[uidx])));
        *(v4sf*)&u[uidx] = *(v4sf*)&u[uidx] + (var_9 * ((var_10 * *(v4sf*)&_vOld[uidx]) - *(v4sf*)&u[uidx]));
        *(v4sf*)&gG[uidx] = *(v4sf*)&gG[uidx] * var_11;
        *(v4sf*)&gN[uidx] = *(v4sf*)&gN[uidx] * var_12;
        *(v4sf*)&ip[uidx] = var_13;
        *(v4sf*)&in[uidx] = var_14;
    }
}

int main()
{
    int num = 500000;
    Unit* units = new Unit(num);
    
    int d = 10000;
    double start = getCurrentTime();
    for(int i = 0; i < d; i ++)
    {
        units->Update(num);
    }
    double end = getCurrentTime();
    cout<<"Time is "<<end-start<<endl;
    return 0;
}

approach2.cpp

#include <iostream>
#include <sys/time.h>

typedef float v4sf __attribute__ ((vector_size(16)));


using namespace std;


class Config
{
public:
   ///////////////////// Class vars declaration /////////////////////////

   static float c_a[ 3 ];
   static float c_b[ 3 ];
   static float c_c[ 3 ];
   static float c_d[ 3 ];
   static float c_e[ 3 ];
   static float c_f[ 3 ];
   static float c_g[ 3 ];
   static float c_h[ 3 ];
   static float c_i[ 3 ];
   static float c_j[ 3 ];

};

Config configObj;

//Config configObj;

#define __CLASSNAME__ Config

//////////// Class vars initialization ////////
float __CLASSNAME__::c_a[ 3 ] = { 0, 0.02, 0.1 };
float __CLASSNAME__::c_b[ 3 ] = { 0, 0.2, 0.2 };
float __CLASSNAME__::c_c[ 3 ] = { 0, -65.0, -65.0 };
float __CLASSNAME__::c_d[ 3 ] = { 0, 8.0, 2.0 };
float __CLASSNAME__::c_e[ 3 ] = { 0, 1.0, 1.0 };
float __CLASSNAME__::c_f[ 3 ] = { 0, 0.9, 0.9 };
float __CLASSNAME__::c_g[ 3 ] = { 0, 0, 0 };
float __CLASSNAME__::c_h[ 3 ] = { 0, 1.0, 1.0 };
float __CLASSNAME__::c_i[ 3 ] = { 0, 0.8582, 0.8582 };
float __CLASSNAME__::c_j[ 3 ] = { 0, 0, 0 };

class Unit
{

public:

   ~Unit();
   Unit(int num_of_instances);
   void Update( int num );

   public:
   ///////////////////// Instance vars declaration ///////////////////////
   float * ip;
   float * in;
   float * v;
   float * u;
   float * gG;
   float * gN;
   float * PN;
   float * _gs;
   float * _ns;
   float * _vslow;
   float * _v0;
   float * _vOld;
   char* buffer;

};

Unit::Unit(int num_of_instances)
{

   //////////// InstanceScalarVars initialization /////////////
   buffer = new char[12*sizeof(float)*num_of_instances];
   char* tmp = buffer;
   ip = new(buffer) float [num_of_instances];

   in = new(buffer+sizeof(float)*num_of_instances) float [num_of_instances];
   v = new(buffer+2*sizeof(float)*num_of_instances) float [num_of_instances];
   u = new(buffer+3*sizeof(float)*num_of_instances) float [num_of_instances];
   gG = new(buffer+4*sizeof(float)*num_of_instances) float [num_of_instances];

   gN = new(buffer+5*sizeof(float)*num_of_instances) float [num_of_instances];
   PN = new (buffer+6*sizeof(float)*num_of_instances) float[num_of_instances];
   _gs = new(buffer+7*sizeof(float)*num_of_instances) float [num_of_instances];
   _ns = new(buffer+8*sizeof(float)*num_of_instances) float [num_of_instances];

   _vslow = new(buffer+9*sizeof(float)*num_of_instances) float [num_of_instances];
   _v0 = new(buffer+10*sizeof(float)*num_of_instances) float [num_of_instances];
   _vOld = new(buffer+11*sizeof(float)*num_of_instances) float [num_of_instances];
   buffer=tmp;

  //cout<<"Absolute address:"<<ip<<" "<<in<<" "<<v<<" "<<u<<" "<<gG<<" "<<gN<<endl;
}



Unit::~Unit()
{
    delete[] buffer;
}

double getCurrentTime(){
   struct timeval curr;
   struct timezone tz;
   gettimeofday(&curr, &tz);
   double tmp = static_cast<double>(curr.tv_sec) * static_cast<double>(1000000)
         + static_cast<double>(curr.tv_usec);
   return tmp*1e-6;
}

void Unit::Update(int num)
{
    v4sf var_0 = {configObj.c_e[1],configObj.c_e[1],configObj.c_e[1],configObj.c_e[1]};
    v4sf var_1 = {configObj.c_g[1],configObj.c_g[1],configObj.c_g[1],configObj.c_g[1]};
    v4sf var_2 = {80,80,80,80};
    v4sf var_3 = {configObj.c_j[1],configObj.c_j[1],configObj.c_j[1],configObj.c_j[1]};
    v4sf var_4 = {0.5,0.5,0.5,0.5};
    v4sf var_5 = {0.04,0.04,0.04,0.04};
    v4sf var_6 = {5,5,5,5};
    v4sf var_7 = {140,140,140,140};
    v4sf var_8 = {configObj.c_i[1],configObj.c_i[1],configObj.c_i[1],configObj.c_i[1]};
    v4sf var_9 = {configObj.c_a[1],configObj.c_a[1],configObj.c_a[1],configObj.c_a[1]};
    v4sf var_10 = {configObj.c_b[1],configObj.c_b[1],configObj.c_b[1],configObj.c_b[1]};
    v4sf var_11 = {configObj.c_f[1],configObj.c_f[1],configObj.c_f[1],configObj.c_f[1]};
    v4sf var_12 = {configObj.c_h[1],configObj.c_h[1],configObj.c_h[1],configObj.c_h[1]};
    v4sf var_13 = {0,0,0,0};
    v4sf var_14 = {0,0,0,0};


    for( int uidx = 0; uidx < num; uidx+=4 )
    {
        *(v4sf*)&_vOld[uidx] = *(v4sf*)&v[uidx];
        *(v4sf*)&gG[uidx] = *(v4sf*)&gG[uidx] + (var_0 * *(v4sf*)&in[uidx]);
        *(v4sf*)&gN[uidx] = *(v4sf*)&gN[uidx] + (var_1 * *(v4sf*)&ip[uidx]);
        *(v4sf*)&_gs[uidx] = *(v4sf*)&gG[uidx] * (*(v4sf*)&v[uidx] + var_2);
        *(v4sf*)&_ns[uidx] = *(v4sf*)&gN[uidx] * *(v4sf*)&v[uidx];
        *(v4sf*)&_vslow[uidx] = *(v4sf*)&v[uidx] - (*(v4sf*)&_ns[uidx] + *(v4sf*)&_gs[uidx]);
        *(v4sf*)&_v0[uidx] = *(v4sf*)&_vslow[uidx] + (var_3 * *(v4sf*)&PN[uidx]);
        *(v4sf*)&v[uidx] = *(v4sf*)&v[uidx] + var_4 * (((var_5 * *(v4sf*)&v[uidx] + var_6) * *(v4sf*)&v[uidx] + var_7) - (*(v4sf*)&u[uidx] - (var_8 * *(v4sf*)&ip[uidx])));
        *(v4sf*)&u[uidx] = *(v4sf*)&u[uidx] + (var_9 * ((var_10 * *(v4sf*)&_vOld[uidx]) - *(v4sf*)&u[uidx]));
        *(v4sf*)&gG[uidx] = *(v4sf*)&gG[uidx] * var_11;
        *(v4sf*)&gN[uidx] = *(v4sf*)&gN[uidx] * var_12;
        *(v4sf*)&ip[uidx] = var_13;
        *(v4sf*)&in[uidx] = var_14;
    }
}

int main()
{
    int num = 500000;
    Unit* units = new Unit(num);
    int d = 10000; 
    double start = getCurrentTime();
    for(int i = 0; i < d; i ++)
    {
        units->Update(num);
    }
    double end = getCurrentTime();
    cout<<"Time is "<<end-start<<endl;
    return 0;
}