[Pkg-opencl-devel] fixing the Intel OpenCL stack

[Andreas Beckmann]

Hi,

I recently started looking into fixing the Intel OpenCL stack 
(spirv-llvm-translater, intel-opencl-clang, intel-graphics-compiler, 
intel-compute-runtime). Since intel-graphics-compiler only supports up 
to llvm-12 (it compiles without error with llvm-13, but crashes when 
building intel-compute-runtime), I've forked the older versions of 
spriv-llvm-translator and intel-opencl-clang that were built with 
llvm-12. They have now passed NEW.

Since spirv-llvm-translater and intel-opencl-clang are tightly coupled 
to the llvm version used, there is probably no point in having 
unversioned -dev packages for them - mixing different llvm versions is a 
source of subtle errors and weird crashes.
I don't plan to rename spirv-llvm-translater and intel-opencl-clang 
(which are built against llvm-13), but just add a virtual versioned 
-13-dev package for them to avoid NEW. When switching to llvm-14, we 
need to introduce new versioned source packages and NEW processing anyway.
(The unversined source packages will eventually go away with llvm-13)

I've prepared "preview" branches for all 4 source packages. If you don't 
mind, I'll add myself to the Uploaders and upload them to sid.
I'm sticking with the versions currently in sid for now. Once 
intel-opencl-icd is back in testing, I'll look at newer upstream versions.
(Latest intel-compute-runtime needs a newer intel-graphics-compiler, but 
that does still not support llvm-13; latest intel-graphics-compiler 
seems to require the sources of spirv-tools (and maybe -headers, too) to 
build).

For intel-opencl-icd (src:intel-compute-runtime) I'd need help from 
someone that has the appropriate hardware to use that ICD. I'm not sure 
how tight the dependency on src:intel-graphics-compiler needs to be. (Or 
what combinations of igc version, llvm-version used to build igc, 
default gcc version, libc version) causes crashes.)
Or is there a way to reproduce #994833 without the hardware?

Andreas