Re: [PATCH] Make gcc -align options .config-settable

From: Denis Vlasenko
Date: Fri Oct 08 2004 - 09:12:49 EST


On Friday 08 October 2004 12:20, Andi Kleen wrote:
> Denis Vlasenko <vda@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> writes:
> > Resend.
> >
> > With all alignment options set to 1 (minimum alignment),
> > I've got 5% smaller vmlinux compared to one built with
> > default code alignment.
> >
> > Rediffed against 2.6.9-rc3.
> > Please apply.
>
> I agree with the basic idea (the big alignments also always annoy
> me when I look at disassembly), but I think your CONFIG options
> are far too complicated. I don't think anybody will go as far as
> to tune loops vs function calls.
>
> I would just do a single CONFIG_NO_ALIGNMENTS that sets everything to
> 1, that should be enough.

For me, yes, but there are people which are slightly less obsessed
with code size than me.

They might want to say "try to align to 16 bytes if
it costs less than 5 bytes" etc.

Also bencmarking people may do little research on real usefulness of
various kinds of alignment.
--
vda
-
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/