Re: [gentoo-dev] [RFC] New USE_EXPAND: LLVM_TARGETS

[Mart Raudsepp]

Ühel kenal päeval, K, 28.09.2016 kell 08:39, kirjutas Michał Górny:
> On Wed, 28 Sep 2016 08:31:06 +0200
> Marek Szuba <marecki@g.o> wrote:
>
> >
> > On 2016-09-27 22:51, Raymond Jennings wrote:
> >
> > >
> > > Doesn't VIDEO_CARDS factor in on xorg-server's video driver
> > > selection?  
> > It does. Which is why with the way things are now, and which
> > Michał's
> > proposal should improve, someone with an amdgpu-compatible card
> > will
> > still have xf86-video-ati lying around - VIDEO_CARDS=radeon will
> > pull it in.
>
> Also note there's VIDEO_CARDS=amdgpu for newer cards, to increase
> your
> confusion. And the LLVM target is probably needed for
> VIDEO_CARDS=radeonsi and newer, not by VIDEO_CARDS=radeon. Though it
> may be needed for OpenCL.

As discussed on IRC, I think the amdgpu target should be enabled via
video_cards_radeonsi, because the only consumer of that target that
pulls it in is currently mesa[video_cards_radeonsi], so users don't
need to go fiddling with yet another USE_EXPAND when they already set
VIDEO_CARDS="radeonsi" or similar anyways in their make.conf.

I don't quite understand the rest of the LLVM_TARGETS proposed. Seems
like all the rest of them would be use.masked and unmasked in specific
arch profiles?
It seems that once you remove AMDGPU from the equation by keeping it
behind VIDEO_CARDS, all the rest are CPU specific stuff, not GPU, so
less mixing things up in a way; though with completely unhelpful
llvm_targets.desc I don't know if any of the others might not be
something else (like BPF, Hexagon, Lanai, MSP430 and more)


And yes, the existing VIDEO_CARDS=radeon* stuff is rather confusing in
mixing up GL driver names, DRM backend names and more, but a separate
issue that I'm thinking on how to clean up and working with the rest of
the x11 team towards something. Meanwhile llvm[video_cards_radeonsi]
would make sure those that need it, already have it if they enable the
thing they need to get it from mesa globally, and won't need to fiddle
with other flags too.
And yes, it's currently llvm[video_cards_radeon] in old versions of
llvm, and that's not accurate anymore since a while imho, and should be
converted to video_cards_radeonsi as well.


Mart