diff options
Diffstat (limited to 'absl/flags/flag_benchmark.cc')
| -rw-r--r-- | absl/flags/flag_benchmark.cc | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/absl/flags/flag_benchmark.cc b/absl/flags/flag_benchmark.cc index 9982b604..57584f85 100644 --- a/absl/flags/flag_benchmark.cc +++ b/absl/flags/flag_benchmark.cc @@ -103,8 +103,17 @@ std::string AbslUnparseFlag(const UDT&) { return ""; } #define FLAG_DEF(T) ABSL_FLAG(T, T##_flag, {}, ""); +#if defined(__clang__) && defined(__linux__) +// Force the flags used for benchmarks into a separate ELF section. +// This ensures that, even when other parts of the code might change size, +// the layout of the flags across cachelines is kept constant. This makes +// benchmark results more reproducible across unrelated code changes. +#pragma clang section data = ".benchmark_flags" +#endif BENCHMARKED_TYPES(FLAG_DEF) - +#if defined(__clang__) && defined(__linux__) +#pragma clang section data = "" +#endif // Register thousands of flags to bloat up the size of the registry. // This mimics real life production binaries. #define DEFINE_FLAG_0(name) ABSL_FLAG(int, name, 0, ""); @@ -130,7 +139,7 @@ namespace { benchmark::DoNotOptimize(absl::GetFlag(FLAGS_##T##_flag)); \ } \ } \ - BENCHMARK(BM_GetFlag_##T); + BENCHMARK(BM_GetFlag_##T)->ThreadRange(1, 16); BENCHMARKED_TYPES(BM_GetFlag) |