[LLVMdev] Query on optimization and tail call.

[Mahadevan R]

Thanks for the clarifications (and unnecessary interruptions on your
time!). But one more query please!

This one generates optimized (computes the value) code:

unsigned sum(unsigned n)
{
  if (n == 0)
    return 0;
  else
    return n + sum(n-1);
}

where as this one generates a loop that adds up numbers:

int sum(int n)
{
  if (n <= 0)
    return 0;
  else
    return n + sum(n-1);
}

I'm guessing this is probably because the values will be different in
the overflow case -- is it?. Although changing the if condition to "if
(n <= 0 || n > 10)" also generates the loop.

Thanks for your patience!
-Mahadevan.