Re: [Sbcl-devel] Potential optimization issue?

[Juho S. <js...@ik...>]

"Marko Koci=E6" <mar...@gm...> writes:
> What went wrong, me or optimizer?
[...]
> After that I tried to optimize it using the following code:
> (defun cycle-length (n)
>   (declare (optimize (speed 3)(debug 0)(safety 0)))
>   (declare (fixnum n))
>    (the fixnum
>      (1+
>       (cond ((eq n 1) 0)
> 	    ((oddp n) (cycle-length (1+ (the fixnum (* 3 n)))))
> 	    (t (cycle-length (/ n 2)))))))

Removing the (safety 0) should answer that question :-) Your fixnum
calculations are overflowing to negative numbers.

--=20
Juho Snellman