gprof's annotated source listing duplicates the source code of the program, labelling each line of code with the number of times it was executed. In this example, we see a function that was called twice, using each branch of an if/else statement once, and including a loop that ran 26,312 times.
ulg updcrc(s, n)
uch *s;
unsigned n;
2 ->{
register ulg c;
static ulg crc = (ulg)0xffffffffL;
2 -> if (s == NULL) {
1 -> c = 0xffffffffL;
1 -> } else {
1 -> c = crc;
1 -> if (n) do {
26312 -> c = crc_32_tab[...];
26312,1,26311 -> } while (--n);
}
2 -> crc = c;
2 -> return c ^ 0xffffffffL;
2 ->}