[SYCL][Driver] Enhance -Xarch_device and -Xarch_host for sycl

[jinge90]

Add simple support to enhance -Xarch_device and -Xarch_host in sycl offloading which can support multiple arguments in single '-Xarch_*' and '-mllvm ' is supported as well.

[jinge90]

Hi, @mdtoguchi and @AaronBallman
As we discussed before, this draft patch implements "--target-options=" and "--host-options=", could you help review whether the work is in correct direction?
Thanks very much.

[mdtoguchi]

I encountered other options: -Xarch_host <arg> and -Xarch_device <arg> which can be used to push options to either the host or device compilation. Quick checking shows this works for various options, but does not work for any options that take arguments (like -mllvm <opt>). Would it make more sense to leverage that instead of introducing new options?

[jinge90]

-mllvm

Hi, @mdtoguchi
Nice finding! I think -Xarch_device and -Xarch_host have almost same behavior as --target-options and --host-options except flag such as '-mllvm ' and if users want to pass a series of flags, they need to type -Xarch_device or -Xarch_host multiple times.
I updated the patch to enhance current -Xarch_device and -Xarch_host, with it, users can pass a series of options via a single -Xarch_device/host like:
clang++ -fsycl test.cpp -Xarch_device "-fsanitize=address -DMY_DUMMY_MACRO -mllvm -enable-merge-functions ...."
This command will be translated to following internally:
clang++ -fsycl test.cpp -Xarch_device -fsanitize=address -Xarch_device -DMY_DUMMY_MACRO -Xarch -mllvm=-enable-merge-functions ....
As you can see '-mllvm ' will be converted to '-mllvm=' and passed to -Xarch_device or -Xarch_host.
Do you think we can proceed with this approach?
Thanks very much.

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[mdtoguchi]

This looks OK to me. I did notice that currently this implementation does not apply to Windows. Moving forward, we should add Windows support.

[jinge90]

This looks OK to me. I did notice that currently this implementation does not apply to Windows. Moving forward, we should add Windows support.

Hi, @mdtoguchi
Thanks for pointing out this, I will create another PR to add tests for Windows target.
Thanks very much.

[jinge90]

Hi, @intel/llvm-gatekeepers
Could you help merge this patch?
Thanks very much.