jhuber6 added inline comments.
================ Comment at: clang/lib/Driver/Driver.cpp:4132-4134 + Archs.insert(CudaArchToString(CudaArch::SM_35)); + else if (Kind == Action::OFK_HIP) + Archs.insert(CudaArchToString(CudaArch::GFX803)); ---------------- tra wrote: > JonChesterfield wrote: > > tra wrote: > > > If we do not have constants for the default CUDA/HIP arch yet, we should > > > probably add them and use them here. > > Defaulting hip to gfx803 is unlikely to be helpful. It won't run on other > > architectures, i.e. there's no conservative default that will run on most > > things. I guess that's an existing quirk of the hip toolchain? > I agree that there's no "safe" choice of GPU target. It applies to CUDA, as > well, at least for GPU binaries. > That said, we still want `clang -c foo.cu` to work. > > For CUDA we use the oldest variant still supported by the vendor. It produces > PTX assembly which we embed along with the GPU binary. > That PTX is valid for newer GPU archtectures and CUDA runtime will be able to > compile it for the GPU the app happens to run on. It's not ideal, but it > works. > > While for AMDGPU we do not have such forward compatibility mode as we have > with CUDA, being able to compile for *something* by default is still useful, > IMO. > > I just copied GFX803 because that's what the previous driver used. I agree we should just default to something, maybe in the AMD case we can issue a warning telling them to use the flag to properly specify it. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D120272/new/ https://reviews.llvm.org/D120272 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
