yaxunl added a comment. In D137154#3904810 <https://reviews.llvm.org/D137154#3904810>, @hdelan wrote:
> In DPC++ for CUDA we use libclc as a wrapper around CUDA SDK's libdevice. > Like libdevice we want to precompile libclc to bc for the CUDA backend > without specializing for a particular arch, so that we can call different > __nv funcs based on the arch. For this reason we use the `__nvvm_reflect` > llvm intrinsic. > > Without a clang builtin a number of workarounds are necessary to get the > desired behaviour from `__nvvm_reflect`. > > 1. We must declare `__nvvm_reflect` in source code everywhere where it is > used. > 2. Some addrspace casting is necessary in openCL, since strings are in > the__constant address space. We must use an IR wrapper function to ensure the > correct behaviour. See > https://github.com/intel/llvm/blob/sycl/libclc/ptx-nvidiacl/libspirv/reflect.ll > > We agree that `__nvvm_reflect` is not a perfect solution, but it is something > we must use because of libdevice. Adding the clang builtin would enable us to > write libdevice-like libraries without having to resort to the methods > mentioned above. LLVM does not maintain bitcode backward compatibility between major releases. How do you make sure the clang/LLVM you are using is compatible with libdevice? Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D137154/new/ https://reviews.llvm.org/D137154 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
