<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">According to LLNL RAJA team (<a href="https://github.com/LLNL/RAJA/issues/372#issuecomment-351795449">https://github.com/LLNL/RAJA/issues/372#issuecomment-351795449</a>), clang-ykt repo is stale and IBM progressing code in private repo for DOE/LLNL.<div><br></div><div>I have no idea when IBM will release latest GPU support but am optimistic that it will happen eventually. I can imagine that they’re focused on contract deliverables and don’t want to be distracted by other issues.</div><div><br></div><div>Jeff<br><br><div id="AppleMailSignature">Sent from my iPhone</div><div><br>On Dec 18, 2017, at 7:33 AM, Jonas Hahnfeld via Openmp-dev <<a href="mailto:openmp-dev@lists.llvm.org">openmp-dev@lists.llvm.org</a>> wrote:<br><br></div><blockquote type="cite"><div><span>Hi,</span><br><span></span><br><span>the answer is the same as in October: (upstream) Clang 5 doesn't fully support offloading to GPUs. Trunk's support has progressed since then but AFAIK still isn't able to link applications at the moment.</span><br><span></span><br><span>Regards,</span><br><span>Jonas</span><br><span></span><br><span>Am 2017-12-18 16:11, schrieb Eichstaedt, Jan R via Openmp-dev:</span><br><blockquote type="cite"><span>Hello,</span><br></blockquote><blockquote type="cite"><span>in addition to my previous mail:</span><br></blockquote><blockquote type="cite"><span>I saw in this year's October archive, that Gabriele Jost has been</span><br></blockquote><blockquote type="cite"><span>running into similar issue. Do you know if and how it has been</span><br></blockquote><blockquote type="cite"><span>resolved for him?</span><br></blockquote><blockquote type="cite"><span>Further, I tried out the clang-ykt git repo, and compiled in the same</span><br></blockquote><blockquote type="cite"><span>fashion as I did with v5, which worked fine for some small test-cases.</span><br></blockquote><blockquote type="cite"><span>This is why I am still quite surprised I ran into the mentioned</span><br></blockquote><blockquote type="cite"><span>compile issue with v5. That said, I assume you merged the clang-ykt</span><br></blockquote><blockquote type="cite"><span>branch into the v5 branch?</span><br></blockquote><blockquote type="cite"><span>The problem with the clang-ykt branch for me however is, that I run</span><br></blockquote><blockquote type="cite"><span>into some mysterious linking errors when compiling our major</span><br></blockquote><blockquote type="cite"><span>framework.</span><br></blockquote><blockquote type="cite"><span>Would you be able to kindly shed some light on this issue?</span><br></blockquote><blockquote type="cite"><span>Thanks and kind regards,</span><br></blockquote><blockquote type="cite"><span>Jan</span><br></blockquote><blockquote type="cite"><span>-------------------------</span><br></blockquote><blockquote type="cite"><span>FROM: Eichstaedt, Jan R</span><br></blockquote><blockquote type="cite"><span>SENT: 14 December 2017 11:39:00</span><br></blockquote><blockquote type="cite"><span>TO: Gheorghe-Teod Bercea</span><br></blockquote><blockquote type="cite"><span>CC: via Openmp-dev</span><br></blockquote><blockquote type="cite"><span>SUBJECT: Re: [Openmp-dev] offloading to Nvidia GPUs</span><br></blockquote><blockquote type="cite"><span>Hello,</span><br></blockquote><blockquote type="cite"><span>both your suggestions of adding the compile flags</span><br></blockquote><blockquote type="cite"><span> -Xopenmp-target=nvptx64-nvidia-cuda -march=sm_35</span><br></blockquote><blockquote type="cite"><span> -Xopenmp-target -march=sm_35</span><br></blockquote><blockquote type="cite"><span>still give me exactly the same error message.</span><br></blockquote><blockquote type="cite"><span>Do you have any other suggestions?</span><br></blockquote><blockquote type="cite"><span>Cheers,</span><br></blockquote><blockquote type="cite"><span>Jan</span><br></blockquote><blockquote type="cite"><span>-------------------------</span><br></blockquote><blockquote type="cite"><span>FROM: Gheorghe-Teod Bercea <<a href="mailto:Gheorghe-Teod.Bercea@ibm.com">Gheorghe-Teod.Bercea@ibm.com</a>></span><br></blockquote><blockquote type="cite"><span>SENT: 13 December 2017 18:30:00</span><br></blockquote><blockquote type="cite"><span>TO: Eichstaedt, Jan R</span><br></blockquote><blockquote type="cite"><span>CC: via Openmp-dev</span><br></blockquote><blockquote type="cite"><span>SUBJECT: Re: [Openmp-dev] offloading to Nvidia GPUs</span><br></blockquote><blockquote type="cite"><span>Hi,</span><br></blockquote><blockquote type="cite"><span>Yes there is:</span><br></blockquote><blockquote type="cite"><span>-Xopenmp-target=nvptx64-nvidia-cuda -march=sm_35</span><br></blockquote><blockquote type="cite"><span>You may also run into the problem that target offloading is not yet</span><br></blockquote><blockquote type="cite"><span>fully supported.</span><br></blockquote><blockquote type="cite"><span>Hope this helps!</span><br></blockquote><blockquote type="cite"><span>Thanks,</span><br></blockquote><blockquote type="cite"><span>--Doru</span><br></blockquote><blockquote type="cite"><span>From: "Eichstaedt, Jan R via Openmp-dev"</span><br></blockquote><blockquote type="cite"><span><<a href="mailto:openmp-dev@lists.llvm.org">openmp-dev@lists.llvm.org</a>></span><br></blockquote><blockquote type="cite"><span>To: via Openmp-dev <<a href="mailto:openmp-dev@lists.llvm.org">openmp-dev@lists.llvm.org</a>></span><br></blockquote><blockquote type="cite"><span>Date: 12/13/2017 01:11 PM</span><br></blockquote><blockquote type="cite"><span>Subject: [Openmp-dev] offloading to Nvidia GPUs</span><br></blockquote><blockquote type="cite"><span>Sent by: "Openmp-dev" <<a href="mailto:openmp-dev-bounces@lists.llvm.org">openmp-dev-bounces@lists.llvm.org</a>></span><br></blockquote><blockquote type="cite"><span>-------------------------</span><br></blockquote><blockquote type="cite"><span>Hello,</span><br></blockquote><blockquote type="cite"><span>I am using llvm and clang version 5.0.0 together with the openmp</span><br></blockquote><blockquote type="cite"><span>project of that version on Ubuntu 16.04.</span><br></blockquote><blockquote type="cite"><span>I try to compile a simple program involving a _#pragma omp target</span><br></blockquote><blockquote type="cite"><span>teams distribute parallel for _statement to offload to a Nvidia-GPU</span><br></blockquote><blockquote type="cite"><span>using the following flags:</span><br></blockquote><blockquote type="cite"><span>-fopenmp=libomp -fopenmp-targets=nvptx64-nvidia-cuda</span><br></blockquote><blockquote type="cite"><span>--cuda-path=/usr/local/cuda/ --cuda-gpu-arch=sm_35</span><br></blockquote><blockquote type="cite"><span>However, the compilation fails, with the following being the first</span><br></blockquote><blockquote type="cite"><span>assertion that is triggered:</span><br></blockquote><blockquote type="cite"><span>clang++:</span><br></blockquote><blockquote type="cite"><span>[...]/llvm-5.0.0.src/tools/clang/lib/Driver/ToolChains/Cuda.cpp:346:</span><br></blockquote><blockquote type="cite"><span>virtual void</span><br></blockquote><blockquote type="cite"><span>clang::driver::toolchains::CudaToolChain::addClangTargetOptions(const</span><br></blockquote><blockquote type="cite"><span>llvm::opt::ArgList&, llvm::opt::ArgStringList&,</span><br></blockquote><blockquote type="cite"><span>clang::driver::Action::OffloadKind) const: Assertion `!GpuArch.empty()</span><br></blockquote><blockquote type="cite"><span>&& "Must have an explicit GPU arch."' failed.</span><br></blockquote><blockquote type="cite"><span>Is there a way to pass the GPU architecture differently? Or is target</span><br></blockquote><blockquote type="cite"><span>offloading not fully supported in v5.0.0 yet and I might better use</span><br></blockquote><blockquote type="cite"><span>the clang-ykt project? Or have I overlooked something else completely?</span><br></blockquote><blockquote type="cite"><span>Thanks for any help you can offer.</span><br></blockquote><blockquote type="cite"><span>Cheers,</span><br></blockquote><blockquote type="cite"><span>Jan</span><br></blockquote><blockquote type="cite"><span>_______________________________________________</span><br></blockquote><blockquote type="cite"><span>Openmp-dev mailing list</span><br></blockquote><blockquote type="cite"><span><a href="mailto:Openmp-dev@lists.llvm.org">Openmp-dev@lists.llvm.org</a></span><br></blockquote><blockquote type="cite"><span><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_openmp-2Ddev&d=DwIGaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=07Vg8AAyMqlmXvuNhmkojcovioZRarJr9xyWnOr5Klg&m=ZwzC4OwLWlGCMnZozDnqy7VceScVkrvWJ4YIlJh1A6I&s=sxzmJ6FJfccsITZA4_0WsCFXFBLsJaLSKg_arZkOl64&e=">https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_openmp-2Ddev&d=DwIGaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=07Vg8AAyMqlmXvuNhmkojcovioZRarJr9xyWnOr5Klg&m=ZwzC4OwLWlGCMnZozDnqy7VceScVkrvWJ4YIlJh1A6I&s=sxzmJ6FJfccsITZA4_0WsCFXFBLsJaLSKg_arZkOl64&e=</a></span><br></blockquote><blockquote type="cite"><span>[1]</span><br></blockquote><blockquote type="cite"><span>Links:</span><br></blockquote><blockquote type="cite"><span>------</span><br></blockquote><blockquote type="cite"><span>[1]</span><br></blockquote><blockquote type="cite"><span><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_openmp-2Ddev&d=DwIGaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=07Vg8AAyMqlmXvuNhmkojcovioZRarJr9xyWnOr5Klg&m=ZwzC4OwLWlGCMnZozDnqy7VceScVkrvWJ4YIlJh1A6I&s=sxzmJ6FJfccsITZA4_0WsCFXFBLsJaLSKg_arZkOl64&e=">https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.llvm.org_cgi-2Dbin_mailman_listinfo_openmp-2Ddev&d=DwIGaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=07Vg8AAyMqlmXvuNhmkojcovioZRarJr9xyWnOr5Klg&m=ZwzC4OwLWlGCMnZozDnqy7VceScVkrvWJ4YIlJh1A6I&s=sxzmJ6FJfccsITZA4_0WsCFXFBLsJaLSKg_arZkOl64&e=</a></span><br></blockquote><blockquote type="cite"><span>_______________________________________________</span><br></blockquote><blockquote type="cite"><span>Openmp-dev mailing list</span><br></blockquote><blockquote type="cite"><span><a href="mailto:Openmp-dev@lists.llvm.org">Openmp-dev@lists.llvm.org</a></span><br></blockquote><blockquote type="cite"><span><a href="http://lists.llvm.org/cgi-bin/mailman/listinfo/openmp-dev">http://lists.llvm.org/cgi-bin/mailman/listinfo/openmp-dev</a></span><br></blockquote><span>_______________________________________________</span><br><span>Openmp-dev mailing list</span><br><span><a href="mailto:Openmp-dev@lists.llvm.org">Openmp-dev@lists.llvm.org</a></span><br><span><a href="http://lists.llvm.org/cgi-bin/mailman/listinfo/openmp-dev">http://lists.llvm.org/cgi-bin/mailman/listinfo/openmp-dev</a></span><br></div></blockquote></div></body></html>