#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>
#include <iostream>
using namespace std;
//------------------------------------------------------------------
// project def and includes
// this test uses a new version of QueryPerformanceTiming , to measure CPU cycles more precisely using rdtsc asm instr.
#include "QueryPerformanceTiming_rdtsc.h"
#define N_REPETIC 150
// repeat several times each test to extract the minimum time
// and to have the caches filled
#define N_ITER (8)
//big number to have a mean time (but not vey big to avoid cache misses)
int a_int[N_ITER ], b_int[N_ITER ];
float a[N_ITER ], b[N_ITER ];
float c[N_ITER ], d[N_ITER ];
float e[N_ITER ], f[N_ITER ];
float g[N_ITER ], h[N_ITER ];
float z;
int cond1[N_ITER ], cond2[N_ITER ], cond3[N_ITER ];
//////////////////////////////////////////////////////////////////////////////////////////////////////////////
// vectors init
void vectors_init ()
{ int i;
for (i=0;i<N_ITER;i++)
{ // a[i] must have little values to avoid overflow in pp1()
a[i]=(float)rand()/(float)RAND_MAX;
b[i]=(float)i/5;
c[i]=(float)i/6;
d[i]=(float)i/7;
e[i]=(float)i/8;
f[i]=(float)i/9;
g[i]=(float)i/10;
h[i]=(float)i/11;
a_int[i]=i;
cond1[i]=1;
cond3[i]=rand()%2;
}
for (i=0;i<N_ITER;i+=8)
{ // put here the pattern behaviour you want; BTB is very clever !!
cond2[i+0]=1;
cond2[i+1]=0;
cond2[i+2]=1;
cond2[i+3]=1;
cond2[i+4]=0;
cond2[i+5]=1;
cond2[i+6]=1;
cond2[i+7]=1;
}
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////
/// tests
float pp1 ()
{ int i;
z=0.0;
for (i=0;i<N_ITER;i++)
{ z+=a[i]/4;
//z = (z+a[i])*a[i] ; // a longer dependence
//try this one if simple z+=a[i]/4; gives cycles/iteration very near from simple loop
}
return z;
}
float pp2 ()
{ int i;
for (i=0;i<N_ITER;i++)
{ a[i]=3/b[i];
}
return a[N_ITER-1 ];
}
float pp3 ()
{ int i;
for (i=0;i<N_ITER;i++)
{ a[i]=b[i]+c[i]+d[i]+e[i]+f[i]+g[i]+h[i]/4;
}
return a[N_ITER-1 ];
}
float pp4 ()
{ int i;
for (i=0;i<N_ITER;i++)
{ a[i]=b[i]+8;
}
return a[N_ITER-1 ];
}
float pp5a ()
{ int i;
for (i=0;i<N_ITER;i++)
{ if (cond1[i]!=0)
a[i]=b[i]+8;
}
return a[N_ITER-1 ];
}
float pp5b ()
{ int i;
for (i=0;i<N_ITER;i++)
{ if (cond2[i]!=0)
a[i]=b[i]+8;
}
return a[N_ITER-1 ];
}
float pp5c ()
{ int i;
for (i=0;i<N_ITER;i++)
{ if (cond3[i]!=0)
a[i]=b[i]/8;
}
return a[N_ITER-1 ];
}
float pp5d ()
{ int i;
for (i=0;i<N_ITER;i++)
{ int cond_true = (cond3[i]); // condition can be 1 or 0
float result_true = b[i]/8;
int *p_int = (int *)(&result_true );
int mask = (cond_true -1); // the mask can be 0 or 0xFFFFFFFF , that is ,
// a mask to perform AND operations
float result_false = -b[i] ;
int *p_int_false = (int *)(&result_false);
int temp = (*p_int & (~mask)) | (*p_int_false & mask);
// int temp = (*p_int & (~mask)) | (*p_int & mask);
float *p_float = (float *) & temp;
a[i] = * p_float ;
}
/*
// The above code is tricky due to the float/integer mixture.
// If vectors were integer , the integer version would be more understandable:
for (i=0;i<N_ITER;i++)
{
int cond_true = (cond3[i]); // condition can be 1 or 0
int result_true = a_int[i]/8;
int mask = (cond_true -1); // the mask can be 0 or 0xFFFFFFFF , that is , a mask to perform AND operations
a_int[i] = ( result_true & (~mask) ) | ( result_true & mask ) ;
}
*/
return a[N_ITER-1 ];
}
//////////////////////////////////////////////////////////////////////////////////////////////////////////////
int main( int argc, char** argv ) {
float var1,var2,var3,var4,var5a,var5b,var5c,var5d;
int i;
QPTimer c1,c2,c3,c4,c5a,c5b,c5c,c5d;
c1.Calibrate(); //calibrates timer overhead and set cronometer to zero
c2.Calibrate(); //calibrates timer overhead and set cronometer to zero
c3.Calibrate(); //calibrates timer overhead and set cronometer to zero
c4.Calibrate(); //calibrates timer overhead and set cronometer to zero
c5a.Calibrate(); //calibrates timer overhead and set cronometer to zero
c5b.Calibrate(); //calibrates timer overhead and set cronometer to zero
c5c.Calibrate(); //calibrates timer overhead and set cronometer to zero
c5d.Calibrate(); //calibrates timer overhead and set cronometer to zero
vectors_init ();
// measuring tests
for (i=0;i<N_REPETIC;i++)
{ c1.Start(); // start timer
var1=pp1(); // Do the test
c1.Stop(); // stop timer
c1.Reset();
}
vectors_init ();
for (i=0;i<N_REPETIC;i++)
{ c2.Start(); // start timer
var2=pp2(); // Do the test
c2.Stop(); // stop timer
c2.Reset();
}
vectors_init ();
for (i=0;i<N_REPETIC;i++)
{ c3.Start(); // start timer
var3=pp3(); // Do the test
c3.Stop(); // stop timer
c3.Reset();
}
vectors_init ();
for (i=0;i<N_REPETIC;i++)
{ c4.Start(); // start timer
var4=pp4(); // Do the test
c4.Stop(); // stop timer
c4.Reset();
}
vectors_init ();
for (i=0;i<N_REPETIC;i++)
{ c5a.Start(); // start timer
var5a=pp5a(); // Do the test
c5a.Stop(); // stop timer
c5a.Reset();
}
vectors_init ();
for (i=0;i<N_REPETIC;i++)
{ c5b.Start(); // start timer
var5b=pp5b(); // Do the test
c5b.Stop(); // stop timer
c5b.Reset();
}
vectors_init ();
for (i=0;i<N_REPETIC;i++)
{ c5c.Start(); // start timer
var5c=pp5c(); // Do the test
c5c.Stop(); // stop timer
c5c.Reset();
}
vectors_init ();
for (i=0;i<N_REPETIC;i++)
{ c5d.Start(); // start timer
var5d=pp5d(); // Do the test
c5d.Stop(); // stop timer
c5d.Reset();
}
// end of testing
cout << endl << "ONLY PRINTING OUTPUT VARIABLE TO PREVENT THAT THE COMPILER ELIMINATES FUNCTION CALLS: "
<< var1 << ", "<< var2<< ", "<< var3 << ", "<< var4 << ", "<<var5a << ", "<< var5b << ", "<< var5c << ", "<< var5d << endl;
cout << endl << "-Number of iterations N_ITER: " << N_ITER << endl;
cout << endl << "-Number of measures: " << c1.NumberOfMeasures() << endl;
// uncomment this if more timing results were needed:
c1.PrintMinimumTime (" Minimum time in seconds for pp1() is: "); c1.PrintMeanTime (" Mean time in seconds for pp1() is: ");
c1.PrintMinimumCycles (" Minimum time in cycles for pp1() is: "); c1.PrintMeanCycles (" Mean time in cycles for pp1() is : ");
c1.PrintMinimumCyclesByIteration (" Minimum time in cycles for an iteration of pp1() is: ", N_ITER); c2.PrintMinimumCyclesByIteration (" Minimum time in cycles for an iteration of pp2() is: ", N_ITER); c3.PrintMinimumCyclesByIteration (" Minimum time in cycles for an iteration of pp3() is: ", N_ITER); c4.PrintMinimumCyclesByIteration (" Minimum time in cycles for an iteration of pp4() is: ", N_ITER); c5a.PrintMinimumCyclesByIteration (" Minimum time in cycles for an iteration of pp5a() is: ", N_ITER); c5b.PrintMinimumCyclesByIteration (" Minimum time in cycles for an iteration of pp5b() is: ", N_ITER); c5c.PrintMinimumCyclesByIteration (" Minimum time in cycles for an iteration of pp5c() is: ", N_ITER); c5d.PrintMinimumCyclesByIteration (" Minimum time in cycles for an iteration of pp5d() is: ", N_ITER);
cout << endl ;
getchar();
}
