Performance Counter

Hi. I have a problem, I am trying to use the "Performance Counter" for general time measurements. In the documentation there is an example how to use it, so I have used it as a base for my tests. However, I don't get the results I expected. For example, the line C-code "i=3;" takes 104 clock ticks to execute?!

My code:

# include <stdio.h>

//For the performance counter # include "altera_avalon_performance_counter.h"# include "system.h"

# define FUNCTION_SECTION_1 1# define FUNCTION_SECTION_2 2

void function_1 (void)

{

int i=0;

//PERF_COUNTER_0_BASE is defined in system.h

PERF_BEGIN (PERFORMANCE_COUNTER_0_BASE, FUNCTION_SECTION_1);

i=3; //First Object to measure

PERF_END (PERFORMANCE_COUNTER_0_BASE, FUNCTION_SECTION_1);

}

void function_2 (void)

{

int i=0;

//PERF_COUNTER_0_BASE is defined in system.h

PERF_BEGIN (PERFORMANCE_COUNTER_0_BASE, FUNCTION_SECTION_2);

i=3; //Objects to measure

i=4;

PERF_END (PERFORMANCE_COUNTER_0_BASE, FUNCTION_SECTION_2);

}

//Turn measurement on & off

int main()

{

// Reset the counters before every run

PERF_RESET (PERFORMANCE_COUNTER_0_BASE);

// Now our program starts in earnest. Begin measuring:

PERF_START_MEASURING (PERFORMANCE_COUNTER_0_BASE);

function_1();

function_2();

PERF_STOP_MEASURING (PERFORMANCE_COUNTER_0_BASE);

//Print the result using "perf_print_formatted_report"

perf_print_formatted_report

(PERFORMANCE_COUNTER_0_BASE,

ALT_CPU_FREQ, // defined in "system.h"

2, // How many sections to print

"function 1",

"function 2"); // Display-name of section(s).

return 0;

}

From this code I get the following results:

--Performance Counter Report--

Total Time: 1.64167E-05 seconds (788 clock-cycles)

+---------------+-----+-----------+---------------+-----------+

| Section | % | Time (sec)| Time (clocks)|Occurrences|

+---------------+-----+-----------+---------------+-----------+

|function 1 | 13.2| 0.00000| 104| 1|

+---------------+-----+-----------+---------------+-----------+

|function 2 | 19.3| 0.00000| 152| 1|

+---------------+-----+-----------+---------------+-----------+

What does it means? What have I done wrong?

/David