Guys.. pls..
There is no performance difference between it++ and ++it. i++ could potentially be slower than ++i, since the old value of i might need to be saved for later use, but in practice all modern compilers will optimize this away.
I can demonstrate this by looking at the code for this function, both with ++i and i++.
$ cat i++.c
extern void g(int i);
void f()
{
int i;
for (i = 0; i < 100; i++)
g(i);
}
The files are the same, except for ++i and i++:
$ diff i++.c ++i.c
6c6
< for (i = 0; i < 100; i++)
---
> for (i = 0; i < 100; ++i)
I 'll compile them, and also get the generated assembler:
So after this we can see that both the generated object and assembler files are the same.
$ md5 i++.s ++i.s
MD5 (i++.s) = 90f620dda862cd0205cd5db1f2c8c06e
MD5 (++i.s) = 90f620dda862cd0205cd5db1f2c8c06e
$ md5 *.o
MD5 (++i.o) = dd3ef1408d3a9e4287facccec53f7d22
MD5 (i++.o) = dd3ef1408d3a9e4287facccec53f7d22
This means, that after compiling both codes are the same.
Both have the same runtime.
Well, I hope that helps.
Best regards , ProfDrBielefeld
