In Windows I use the rdtsc assembler instruction. It returns a 64 bit
integer (in EAX:EDX I think) which represent the amount of processors cycles
that have passed from the last reset. Computing the difference between two
values and taking into account the freq of the CPU (you have to figure it
out somehow), you get a very accurate timer.
Maybe someone can convert this code to Linux:
static __int64 __declspec(naked) rdtsc()
{
__asm
{
rdtsc
ret
}
}
You use it like this:
///////////////////////////////////
__int64 A, B;
A = rdtsc();
// do something
B = rdtsc();
printf("CPU cycles spent: %d\n", (int) (B - A));
///////////////////////////////////
