//very simple array function calculation:
#include "math.h"
#include "time.h"
#include "stdio.h"
static double A[50000000];
int main(int argc, char *argv)
{
for (int t=0;t<50000000;t++)
A[t]=5.55*sin(t); //random data
time_t time0 = clock();
for (int t=0;t<50000000;t++)
A[t]=exp(A[t]);
printf("%g\n", ((double)(clock()-time0))/CLOCKS_PER_SEC);
}
Time for this code compiled with Intel10 compiler is 1.2sec.
Result for code compiled with GCC(v3 and v4) is 7.2sec.
I've tried all optimization options: -mfpmath=sse -msse2 -O3
-mtune=pentium-m
But still intel is 7 times faster.
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