Re: [PATCH GIT 0.6] make use of register variables & size_t

From: Arjan van de Ven
Date: Mon Apr 25 2005 - 15:52:31 EST


On Mon, 2005-04-25 at 11:50 -0700, Linus Torvalds wrote:
>
> On Mon, 25 Apr 2005, Matthias-Christian Ott wrote:
> >
> > But this makes, like "register", direct use of processor registers (it
> > stores int arguments in eax, ebx, etc.).
>
> No. It make _unlike_ "register", direct use of processor registers.
>
> The "register" keyword does _not_ use processor registers. It's just
> syntactic fluff, and tells the compiler exactly one thing:
>
> - that the compiler should warn if you take the address of such a thing.
>
> In addition, the compiler may generate code that takes it into account,
> which most likely means _worse_ code than if it didn't take it into
> account.

afaik gcc just otherwise ignores it entirely.


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/