From 40efbcf0fd348625c892453d915eb7601adda917 Mon Sep 17 00:00:00 2001 From: Tom Stellard Date: Sat, 5 Oct 2024 17:17:33 +0000 Subject: [PATCH 1/2] [Clang][perf-training] Do build of libLLVMSupport for perf training This adds a build of the libLLVMSupport to the lit suite that is used for generating profile data. This helps to improve both PGO and BOLT optimization of clang over the existing hello world training program. I considered building all of LLVM instead of just libLLVMSupport, but there is only a marginal increase in performance for PGO only builds when training with a build of all of LLVM, and I didn't think it was enough to justify the increased build times given that it is the default configuration. The benchmark[1] I did showed that using libLLVMSupport for training gives a 1.35 +- 0.02 speed up for clang optimized with PGO + BOLT vs just 1.05 +- 0.01 speed up when training with hello world. For comparison, training with a full LLVM build gave a speed up of 1.35 +- 0.1. Raw data: | PGO Training | BOLT Training | Speed Up | Error Range | | ------------ | ------------- | -------- | ----------- | | LLVM Support | LLVM Support | 1.35 | 0.02 | | LLVM All | LLVM All | 1.34 | 0.01 | | LLVM Support | Hello World | 1.29 | 0.02 | | LLVM All | PGO-ONLY | 1.27 | 0.02 | | LLVM Support | PGO-ONLY | 1.22 | 0.02 | | Hello World | Hello World | 1.05 | 0.01 | | Hello World | PGO-ONLY | 1.03 | 0.01 | [1] Benchmark was compiling SemaDecl.cpp --- clang/utils/perf-training/bolt.lit.cfg | 3 +++ clang/utils/perf-training/bolt.lit.site.cfg.in | 3 +++ clang/utils/perf-training/lit.cfg | 6 +++++- clang/utils/perf-training/lit.site.cfg.in | 3 +++ clang/utils/perf-training/llvm-support/build.test | 2 ++ 5 files changed, 16 insertions(+), 1 deletion(-) create mode 100644 clang/utils/perf-training/llvm-support/build.test diff --git a/clang/utils/perf-training/bolt.lit.cfg b/clang/utils/perf-training/bolt.lit.cfg index 0e81a5501e9fc..1d0cf9a8a17a8 100644 --- a/clang/utils/perf-training/bolt.lit.cfg +++ b/clang/utils/perf-training/bolt.lit.cfg @@ -49,3 +49,6 @@ config.substitutions.append(("%clang_cpp", f" {config.clang} --driver-mode=g++ " config.substitutions.append(("%clang_skip_driver", config.clang)) config.substitutions.append(("%clang", config.clang)) config.substitutions.append(("%test_root", config.test_exec_root)) +config.substitutions.append(('%cmake_generator', config.cmake_generator)) +config.substitutions.append(('%cmake', config.cmake_exe)) +config.substitutions.append(('%llvm_src_dir', config.llvm_src_dir)) diff --git a/clang/utils/perf-training/bolt.lit.site.cfg.in b/clang/utils/perf-training/bolt.lit.site.cfg.in index 54de12701c1ae..3de5026e4792a 100644 --- a/clang/utils/perf-training/bolt.lit.site.cfg.in +++ b/clang/utils/perf-training/bolt.lit.site.cfg.in @@ -11,6 +11,9 @@ config.python_exe = "@Python3_EXECUTABLE@" config.clang_obj_root = path(r"@CLANG_BINARY_DIR@") config.clang_bolt_mode = "@CLANG_BOLT@" config.clang_bolt_name = "@CLANG_BOLT_INSTRUMENTED@" +config.cmake_exe = "@CMAKE_COMMAND@" +config.llvm_src_dir ="@CMAKE_SOURCE_DIR@" +config.cmake_generator ="@CMAKE_GENERATOR@" # Let the main config do the real work. lit_config.load_config(config, "@CLANG_SOURCE_DIR@/utils/perf-training/bolt.lit.cfg") diff --git a/clang/utils/perf-training/lit.cfg b/clang/utils/perf-training/lit.cfg index 0bd06c0d44f65..b4527c602fc48 100644 --- a/clang/utils/perf-training/lit.cfg +++ b/clang/utils/perf-training/lit.cfg @@ -34,8 +34,12 @@ config.test_format = lit.formats.ShTest(use_lit_shell == "0") config.substitutions.append( ('%clang_cpp_skip_driver', ' %s %s %s ' % (cc1_wrapper, config.clang, sysroot_flags))) config.substitutions.append( ('%clang_cpp', ' %s --driver-mode=g++ %s ' % (config.clang, sysroot_flags))) config.substitutions.append( ('%clang_skip_driver', ' %s %s %s ' % (cc1_wrapper, config.clang, sysroot_flags))) -config.substitutions.append( ('%clang', ' %s %s ' % (config.clang, sysroot_flags) ) ) +config.substitutions.append( ('%clang', '%s %s ' % (config.clang, sysroot_flags) ) ) config.substitutions.append( ('%test_root', config.test_exec_root ) ) +config.substitutions.append( ('%cmake_generator', config.cmake_generator ) ) +config.substitutions.append( ('%cmake', config.cmake_exe ) ) +config.substitutions.append( ('%llvm_src_dir', config.llvm_src_dir ) ) +print(config.substitutions) config.environment['LLVM_PROFILE_FILE'] = 'perf-training-%4m.profraw' diff --git a/clang/utils/perf-training/lit.site.cfg.in b/clang/utils/perf-training/lit.site.cfg.in index fae93065a4edf..9d279d552919a 100644 --- a/clang/utils/perf-training/lit.site.cfg.in +++ b/clang/utils/perf-training/lit.site.cfg.in @@ -8,6 +8,9 @@ config.test_exec_root = "@CMAKE_CURRENT_BINARY_DIR@" config.test_source_root = "@CLANG_PGO_TRAINING_DATA@" config.target_triple = "@LLVM_TARGET_TRIPLE@" config.python_exe = "@Python3_EXECUTABLE@" +config.cmake_exe = "@CMAKE_COMMAND@" +config.llvm_src_dir ="@CMAKE_SOURCE_DIR@" +config.cmake_generator ="@CMAKE_GENERATOR@" # Let the main config do the real work. lit_config.load_config(config, "@CLANG_SOURCE_DIR@/utils/perf-training/lit.cfg") diff --git a/clang/utils/perf-training/llvm-support/build.test b/clang/utils/perf-training/llvm-support/build.test new file mode 100644 index 0000000000000..f29a594c84686 --- /dev/null +++ b/clang/utils/perf-training/llvm-support/build.test @@ -0,0 +1,2 @@ +RUN: %cmake -G %cmake_generator -B %t -S %llvm_src_dir -DCMAKE_C_COMPILER=%clang -DCMAKE_CXX_COMPILER=%clang -DCMAKE_CXX_FLAGS="--driver-mode=g++" -DCMAKE_BUILD_TYPE=Release +RUN: %cmake --build %t -v --target LLVMSupport From 37919a76e3d3aa9456e1c598eab28a2c1f5155bc Mon Sep 17 00:00:00 2001 From: Tom Stellard Date: Wed, 9 Oct 2024 21:50:36 +0000 Subject: [PATCH 2/2] Remove debug statement --- clang/utils/perf-training/lit.cfg | 1 - 1 file changed, 1 deletion(-) diff --git a/clang/utils/perf-training/lit.cfg b/clang/utils/perf-training/lit.cfg index b4527c602fc48..654961e215da6 100644 --- a/clang/utils/perf-training/lit.cfg +++ b/clang/utils/perf-training/lit.cfg @@ -40,6 +40,5 @@ config.substitutions.append( ('%cmake_generator', config.cmake_generator ) ) config.substitutions.append( ('%cmake', config.cmake_exe ) ) config.substitutions.append( ('%llvm_src_dir', config.llvm_src_dir ) ) -print(config.substitutions) config.environment['LLVM_PROFILE_FILE'] = 'perf-training-%4m.profraw'