Re: gcc inlining heuristics was Re: [PATCH -v7][RFC]: mutex: implement adaptive spinning

Andi Kleen
2009-01-12T00:38:20Z

On Sun, Jan 11, 2009 at 04:21:03PM -0800, Linus Torvalds wrote:
>
>
> On Mon, 12 Jan 2009, Andi Kleen wrote:
> >
> > so at least least for this case it works. Your case also doesn't work
> > for me. So it looks like gcc didn't like something you did in your test
> > program.
>
> I very intentionally used _different_ types.
>
> If you use the same type, gcc will apparenrly happily say "hey, I can
> combine two variables of the same type with different liveness into the
> same variable".

Confirmed.

> But that's not the interesting case.

Weird. I wonder where this strange restriction comes from. It indeed
makes this much less useful than it could be :/

-Andi
--
ak@linux.intel.com