[libc++][format] Adds formatting benchmarks.
These benchmarks will be used to test the performance inpact of the next
set of optimization patches.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D110501
NOKEYCHECK=True
GitOrigin-RevId: 01631ffcfca768c97e4a26c2d86af1ecb4b28b22
diff --git a/benchmarks/format.bench.cpp b/benchmarks/format.bench.cpp
new file mode 100644
index 0000000..89f1132
--- /dev/null
+++ b/benchmarks/format.bench.cpp
@@ -0,0 +1,36 @@
+//===----------------------------------------------------------------------===//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include <format>
+
+#include <string>
+
+#include "benchmark/benchmark.h"
+#include "make_string.h"
+
+#define CSTR(S) MAKE_CSTRING(CharT, S)
+
+template <class CharT>
+static void BM_format_string(benchmark::State& state) {
+ size_t size = state.range(0);
+ std::basic_string<CharT> str(size, CharT('*'));
+
+ while (state.KeepRunningBatch(str.size()))
+ benchmark::DoNotOptimize(std::format(CSTR("{}"), str));
+
+ state.SetBytesProcessed(state.iterations() * size * sizeof(CharT));
+}
+BENCHMARK_TEMPLATE(BM_format_string, char)->RangeMultiplier(2)->Range(1, 1 << 20);
+BENCHMARK_TEMPLATE(BM_format_string, wchar_t)->RangeMultiplier(2)->Range(1, 1 << 20);
+
+int main(int argc, char** argv) {
+ benchmark::Initialize(&argc, argv);
+ if (benchmark::ReportUnrecognizedArguments(argc, argv))
+ return 1;
+
+ benchmark::RunSpecifiedBenchmarks();
+}