================ @@ -0,0 +1,82 @@ +======================= +Clang SYCL Linker +======================= + +.. contents:: + :local: + +.. _clang-sycl-linker: + +Introduction +============ + +This tool works as a wrapper around the SYCL device code linking process. +The purpose of this tool is to provide an interface to link SYCL device bitcode +in LLVM IR format, SYCL device bitcode in SPIR-V IR format, and native binary +objects, and then use the SPIR-V LLVM Translator tool on fully linked device +objects to produce the final output. +After the linking stage, the fully linked device code in LLVM IR format may +undergo several SYCL-specific finalization steps before the SPIR-V code +generation step. +The tool will also support the Ahead-Of-Time (AOT) compilation flow. AOT +compilation is the process of invoking the back-end at compile time to produce +the final binary, as opposed to just-in-time (JIT) compilation when final code +generation is deferred until application runtime. + +Device code linking for SYCL offloading has several known quirks that +make it difficult to use in a unified offloading setting. Two of the primary +issues are: +1. Several finalization steps are required to be run on the fully linked LLVM +IR bitcode to guarantee conformance to SYCL standards. This step is unique to +the SYCL offloading compilation flow. +2. The SPIR-V LLVM Translator tool is an external tool and hence SPIR-V IR code +generation cannot be done as part of LTO. This limitation can be lifted once +the SPIR-V backend is available as a viable LLVM backend. + +This tool has been proposed to work around these issues. + +Usage +===== + +This tool can be used with the following options. Several of these options will +be passed down to downstream tools like 'llvm-link', 'llvm-spirv', etc. + +.. code-block:: console + + OVERVIEW: A utility that wraps around the SYCL device code linking process. + This enables linking and code generation for SPIR-V JIT targets and AOT + targets. + + USAGE: clang-sycl-linker [options] + + OPTIONS: + --arch <value> Specify the name of the target architecture. + --dry-run Print generated commands without running. + -g Specify that this was a debug compile. + -help-hidden Display all available options + -help Display available options (--help-hidden for more) + --library-path=<dir> Set the library path for SYCL device libraries + --device-libs=<value> A comma separated list of device libraries that are linked during the device link ---------------- jhuber6 wrote:
Why are device libs and regular input distinct? https://github.com/llvm/llvm-project/pull/112245 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
