================ @@ -240,6 +240,38 @@ The ``BOOTSTRAP_LLVM_ENABLE_LTO=Thin`` will enable ThinLTO for stage 2 and stage 3 in case the compiler used for stage 1 does not support the ThinLTO option. +Distributed ThinLTO (DTLTO) +--------------------------- + +DTLTO allows for the distribution of backend ThinLTO compilations via external +distribution systems, e.g. Incredibuild. There is existing support for +distributing ThinLTO compilations by using separate thin-link, backend +compilation, and link steps coordinated by a build system which can handle the +dynamic dependencies specified by the index files, such as Bazel. However, this +often requires changes to the user's build process. With DTLTO distribution is +managed internally in LLD as part of the traditional link step and therefore +should be usable in any build process that can support in-process ThinLTO. + +DTLTO requires the LLD linker (``-fuse-ld=lld``). + +``-fthinlto-distributor=<path>`` + - Specifies the ``<path>`` to the distributor process executable for DTLTO. + - If specified, ThinLTO backend compilations will be distributed by LLD. + +``-Xdist <arg>`` + - Pass ``<arg>`` to the distributor process (see ``-fthinlto-distributor=``). + - Can be specified multiple times to pass multiple options. + +Examples: + - ``clang -flto=thin -fthinlto-distributor=incredibuild.exe -Xdist --verbose -fuse-ld=lld`` + - ``clang -flto=thin -fthinlto-distributor=$(which python) -Xdist incredibuild.py -fuse-ld=lld`` + +If ``-fthinlto-distributor=`` is specified Clang supplies the path to a +distributable optimization and code generation tool to LLD. Currently this tool +is Clang itself specified. ---------------- ilovepi wrote:
Typo? ```suggestion is Clang itself. ``` https://github.com/llvm/llvm-project/pull/126654 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
