[RFC PATCH u-boot 00/12] U-Boot LTO (Sandbox + ARM Nokia RX-51)

[Adam Ford]

On Thu, Mar 4, 2021 at 4:43 AM Marek Behun <marek.behun at nic.cz> wrote:
>
> On Wed, 3 Mar 2021 16:36:05 -0500
> Tom Rini <trini at konsulko.com> wrote:
>
> > So, as I start testing things locally with two additional changes (1.
> > LTO by default 2. No ffunction/data-sections with LTO) we see:
> > https://gist.github.com/trini/350ab850c42293563228b8d68a1bb89a
> > as the detailed size reduction.  This also shows that with LTO we want
> > to turn off -ffunction-sections/etc as it's not useful now.
>
> Tom, I have pushed another version to github PR to trigger CI, and am
> still working on clang. You can look at the github PR if you want to
> try yourself. I have also added patch that disables
> -ffunction-section/fdata-section on arm.
>
> After I manage to make it all work in CI I will send v2 to mailing list.

I tested this with the imx6q_logic board.  I only tested the U-Boot
portion, but it appeared to work and it booted the kernel.  The U-Boot
size reduced -7182 bytes (about 3% smaller).

I haven't been able to successfully boot the OMAP3 boards I have yet.
I'm still looking into this.

I don't think we should enable LTO by default for all boards yet.


adam


>
> Marek