diff --git a/clang/utils/perf-training/CMakeLists.txt b/clang/utils/perf-training/CMakeLists.txt index c6d51863fb1b5..93744f4606023 100644 --- a/clang/utils/perf-training/CMakeLists.txt +++ b/clang/utils/perf-training/CMakeLists.txt @@ -1,6 +1,10 @@ +include(LLVMExternalProjectUtils) + set(CLANG_PGO_TRAINING_DATA "${CMAKE_CURRENT_SOURCE_DIR}" CACHE PATH "The path to a lit testsuite containing samples for PGO and order file generation" ) +set(CLANG_PGO_TRAINING_DATA_SOURCE_DIR OFF CACHE STRING "Path to source directory containing cmake project with source files to use for generating pgo data") +set(CLANG_PGO_TRAINING_DEPS "" CACHE STRING "Extra dependencies needed to build the PGO training data.") if(LLVM_BUILD_INSTRUMENTED) configure_lit_site_cfg( @@ -11,11 +15,11 @@ if(LLVM_BUILD_INSTRUMENTED) add_lit_testsuite(generate-profraw "Generating clang PGO data" ${CMAKE_CURRENT_BINARY_DIR}/pgo-data/ EXCLUDE_FROM_CHECK_ALL - DEPENDS clang clear-profraw ${CLANG_PERF_TRAINING_DEPS} + DEPENDS clang clear-profraw ${CLANG_PGO_TRAINING_DEPS} ) add_custom_target(clear-profraw - COMMAND "${Python3_EXECUTABLE}" ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py clean ${CMAKE_CURRENT_BINARY_DIR} profraw + COMMAND "${Python3_EXECUTABLE}" ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py clean ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_BINARY_DIR}/profiles/ profraw COMMENT "Clearing old profraw data") if(NOT LLVM_PROFDATA) @@ -26,9 +30,14 @@ if(LLVM_BUILD_INSTRUMENTED) message(STATUS "To enable merging PGO data LLVM_PROFDATA has to point to llvm-profdata") else() add_custom_target(generate-profdata - COMMAND "${Python3_EXECUTABLE}" ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py merge ${LLVM_PROFDATA} ${CMAKE_CURRENT_BINARY_DIR}/clang.profdata ${CMAKE_CURRENT_BINARY_DIR} + COMMAND "${Python3_EXECUTABLE}" ${CMAKE_CURRENT_SOURCE_DIR}/perf-helper.py merge ${LLVM_PROFDATA} ${CMAKE_CURRENT_BINARY_DIR}/clang.profdata ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_BINARY_DIR}/profiles/ COMMENT "Merging profdata" DEPENDS generate-profraw) + if (CLANG_PGO_TRAINING_DATA_SOURCE_DIR) + llvm_ExternalProject_Add(generate-profraw-external ${CLANG_PGO_TRAINING_DATA_SOURCE_DIR} + USE_TOOLCHAIN EXLUDE_FROM_ALL NO_INSTALL DEPENDS generate-profraw) + add_dependencies(generate-profdata generate-profraw-external) + endif() endif() endif() diff --git a/clang/utils/perf-training/perf-helper.py b/clang/utils/perf-training/perf-helper.py index 99d6a3333b6ef..3e92cd38a7145 100644 --- a/clang/utils/perf-training/perf-helper.py +++ b/clang/utils/perf-training/perf-helper.py @@ -30,26 +30,28 @@ def findFilesWithExtension(path, extension): def clean(args): - if len(args) != 2: + if len(args) < 2: print( - "Usage: %s clean \n" % __file__ + "Usage: %s clean \n" % __file__ + "\tRemoves all files with extension from ." ) return 1 - for filename in findFilesWithExtension(args[0], args[1]): - os.remove(filename) + for path in args[1:-1]: + for filename in findFilesWithExtension(path, args[-1]): + os.remove(filename) return 0 def merge(args): - if len(args) != 3: + if len(args) < 3: print( - "Usage: %s merge \n" % __file__ + "Usage: %s merge \n" % __file__ + "\tMerges all profraw files from path into output." ) return 1 cmd = [args[0], "merge", "-o", args[1]] - cmd.extend(findFilesWithExtension(args[2], "profraw")) + for path in args[2:]: + cmd.extend(findFilesWithExtension(path, "profraw")) subprocess.check_call(cmd) return 0 diff --git a/llvm/docs/AdvancedBuilds.rst b/llvm/docs/AdvancedBuilds.rst index 960b19fa5317f..ee178dd3772c4 100644 --- a/llvm/docs/AdvancedBuilds.rst +++ b/llvm/docs/AdvancedBuilds.rst @@ -145,6 +145,29 @@ that also enables ThinTLO, use the following command: -DPGO_INSTRUMENT_LTO=Thin \ /llvm +By default, clang will generate profile data by compiling a simple +hello world program. You can also tell clang use an external +project for generating profile data that may be a better fit for your +use case. The project you specify must either be a lit test suite +(use the CLANG_PGO_TRAINING_DATA option) or a CMake project (use the +CLANG_PERF_TRAINING_DATA_SOURCE_DIR option). + +For example, If you wanted to use the +`LLVM Test Suite `_ to generate +profile data you would use the following command: + +.. code-block:: console + + $ cmake -G Ninja -C /clang/cmake/caches/PGO.cmake \ + -DBOOTSTRAP_CLANG_PGO_TRAINING_DATA_SOURCE_DIR= \ + -DBOOTSTRAP_CLANG_PGO_TRAINING_DEPS=runtimes + +The BOOTSTRAP\_ prefixes tells CMake to pass the variables on to the instrumented +stage two build. And the CLANG_PGO_TRAINING_DEPS option let's you specify +additional build targets to build before building the external project. The +LLVM Test Suite requires compiler-rt to build, so we need to add the +`runtimes` target as a dependency. + After configuration, building the stage2-instrumented-generate-profdata target will automatically build the stage1 compiler, build the instrumented compiler with the stage1 compiler, and then run the instrumented compiler against the @@ -172,12 +195,12 @@ You can feed that file into the LLVM_PROFDATA_FILE option when you build your optimized compiler. It may be necessary to build additional targets before running perf training, such as -builtins and runtime libraries. You can use the :code:`CLANG_PERF_TRAINING_DEPS` CMake +builtins and runtime libraries. You can use the :code:`CLANG_PGO_TRAINING_DEPS` CMake variable for that purpose: .. code-block:: cmake - set(CLANG_PERF_TRAINING_DEPS builtins runtimes CACHE STRING "") + set(CLANG_PGO_TRAINING_DEPS builtins runtimes CACHE STRING "") The PGO cache has a slightly different stage naming scheme than other multi-stage builds. It generates three stages: stage1, stage2-instrumented, and