benchmark.c

#define REDO_COMPUTATIONS 100
struct results {
  uint32_t doubletime;
  uint32_t floattime;
  uint32_t inttime;
};

#define MAX_LOOPS 512
double MyDoubles[MAX_LOOPS];
double a_d = 12345.67, b_d = 54321.11;
float MyFloats[MAX_LOOPS];
float a_f = 67890.12, b_f = 8756451.17;
int Myints[MAX_LOOPS];
int a_i = 5814411, b_i = 18714;

void math_add (struct results *r) {
  uint32_t t, c;
  int l;
  
  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      MyDoubles [ l ] = double ( a_d + b_d * double ( l ) );
    }
  }
  r->doubletime = micros () - t;

  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      MyFloats [ l ] = float ( a_f + b_f * float ( l ) );
    }
  }
  r->floattime = micros () - t;

  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      Myints [ l ] =  a_i + b_i * l;
    }
  }
  r->inttime = micros () - t;
}

void math_sub (struct results *r) {
  uint32_t t, c;
  int l;
  
  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      MyDoubles [ l ] = double ( a_d - b_d * double ( l ) );
    }
  }
  r->doubletime = micros () - t;

  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      MyFloats [ l ] = float ( a_f - b_f * float ( l ) );
    }
  }
  r->floattime = micros () - t;

  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      Myints [ l ] =  a_i - b_i * l;
    }
  }
  r->inttime = micros () - t;
}

void math_mul (struct results *r) {
  uint32_t t, c;
  int l;
    
  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      MyDoubles [ l ] = double ( a_d * b_d * double ( l ) );
    }
  }
  r->doubletime = micros () - t;

  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      MyFloats [ l ] = float ( a_f * b_f * float ( l ) );
    }
  }
  r->floattime = micros () - t;

  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      Myints [ l ] =  a_i * b_i * l;
    }
  }
  r->inttime = micros () - t;
}

void math_div (struct results *r) {
  uint32_t t, c;
  int l;

  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      MyDoubles [ l ] = double ( a_d / b_d * double ( l ) );
    }
  }
  r->doubletime = micros () - t;

  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      MyFloats [ l ] = float ( a_f / b_f * float ( l ) );
    }
  }
  r->floattime = micros () - t;

  t = micros ();
  for ( c = 0 ; c < REDO_COMPUTATIONS ; c ++ )
  {
    for ( l = 0 ; l < MAX_LOOPS ; l ++ )
    { 
      Myints [ l ] =  a_i / b_i * l;
    }
  }
  r->inttime = micros () - t;
}

#ifdef STM32F4
#define SERIAL_PORT Serial1
#else
#define SERIAL_PORT Serial
#endif

void setup() {
  SERIAL_PORT.begin(115200);
}

void loop() {
  struct results add_ops, sub_ops, mul_ops, div_ops;

  math_add(&add_ops);
  math_sub(&sub_ops);
  math_mul(&mul_ops);
  math_div(&div_ops);

  SERIAL_PORT.print("run ");
  SERIAL_PORT.print(REDO_COMPUTATIONS);
  SERIAL_PORT.println(" times");
  SERIAL_PORT.println("FUNCTION DOUBLE SINGLE INT");
  
  SERIAL_PORT.print("Time - ADD (us/512) :\t ");
  SERIAL_PORT.print( add_ops.doubletime / REDO_COMPUTATIONS );
  SERIAL_PORT.print("\t\t");
  SERIAL_PORT.print( add_ops.floattime / REDO_COMPUTATIONS );
  SERIAL_PORT.print("\t\t");
  SERIAL_PORT.println( add_ops.inttime / REDO_COMPUTATIONS );
  
  SERIAL_PORT.print("Time - SUB (us/512) :\t ");
  SERIAL_PORT.print( sub_ops.doubletime / REDO_COMPUTATIONS );
  SERIAL_PORT.print("\t\t");
  SERIAL_PORT.print( sub_ops.floattime / REDO_COMPUTATIONS );
  SERIAL_PORT.print("\t\t");
  SERIAL_PORT.println ( sub_ops.inttime / REDO_COMPUTATIONS );

  SERIAL_PORT.print ("Time - MUL (us/512) :\t ");
  SERIAL_PORT.print( mul_ops.doubletime / REDO_COMPUTATIONS );
  SERIAL_PORT.print("\t\t");
  SERIAL_PORT.print( mul_ops.floattime / REDO_COMPUTATIONS );
  SERIAL_PORT.print("\t\t");
  SERIAL_PORT.println ( mul_ops.inttime / REDO_COMPUTATIONS );

  SERIAL_PORT.print ("Time - DIV (us/512) :\t ");
  SERIAL_PORT.print( div_ops.doubletime / REDO_COMPUTATIONS );
  SERIAL_PORT.print("\t\t");
  SERIAL_PORT.print( div_ops.floattime / REDO_COMPUTATIONS );
  SERIAL_PORT.print("\t\t");
  SERIAL_PORT.println ( div_ops.inttime / REDO_COMPUTATIONS );
  
  delay(1000);
}