[arch-general] RFC: Mesa and shared LLVM libraries

[Armin K.]

On 03/03/2013 09:04 PM, Armin K. wrote:
> Hello everyone,
>
> First, I am aware that ArchLinux is against patching packages to
> implement some features, but this might be worth the effort.
>
> Tom Stellard of AMD has announced a R600 backend patch against LLVM 3.2
> few days ago [1]. It's basically his repository (llvm-amdgpu-snapshot)
> diffed against upstream LLVM (llvm).
>
> By applying the patch to ArchLinux LLVM package, one could benefit from
> enabling Mesa to link against LLVM shared library. Doing so, space would
> be saved and so the memory at runtime, too (I guess since it will use
> shared mappings).
>
> I've done some work regarding that. I've managed to split libLLVM-3.2.so
> from llvm package and put it into libllvm package.
>
> The package is a bit big though - the shared library contains all (~100)
> static libraries linked into one single library.
>
> The result is like this:
>
> Targets (1): libllvm-3.2-5
>
> Total Installed Size:   21.77 MiB
>
> Building MesaLib against shared libLLVM-3.2.so saves space drastically.
> For all MesaLib produced packages, the output is like this one:
>
> Targets (6): ati-dri-9.1-2  intel-dri-9.1-2  mesa-9.1-2
> mesa-libgl-9.1-2  nouveau-dri-9.1-2  svga-dri-9.1-2
>
> Total Installed Size:   82.13 MiB
> Net Upgrade Size:       -282.07 MiB
>
> 260 MB saved ... Looks nice to me.
>
> R600 backend will be part of LLVM 3.3 anyways, and this can be used in
> the future without patching anything.
>
> I am attaching patches for llvm and mesa PKGBUILDs to incorporate these
> changes. Do as you may please.
>
> If someone is interested in forwarding this to -dev-public list it would
> be nice.
>
> Have a nice evening.
>
> (As a side note, somehow llvm tarball sha256sum was wrong when I
> downloaded it).
>
> [1] http://lists.freedesktop.org/archives/mesa-dev/2013-March/035561.html

Hm, it seems that attachments are blocked

mesa.patch http://paste.debian.net/plainh/638c2e73
llvm.patch http://paste.debian.net/plainh/bd11c4da

As another side note, the 0003 patch available on Tom Stellard's web 
site fails to apply with "patch already applied".