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+// Copyright 2017 The Abseil Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "absl/strings/internal/char_map.h"
+
+#include <cstdint>
+
+#include "benchmark/benchmark.h"
+
+namespace {
+
+absl::strings_internal::Charmap MakeBenchmarkMap() {
+ absl::strings_internal::Charmap m;
+ uint32_t x[] = {0x0, 0x1, 0x2, 0x3, 0xf, 0xe, 0xd, 0xc};
+ for (uint32_t& t : x) t *= static_cast<uint32_t>(0x11111111UL);
+ for (uint32_t i = 0; i < 256; ++i) {
+ if ((x[i / 32] >> (i % 32)) & 1)
+ m = m | absl::strings_internal::Charmap::Char(i);
+ }
+ return m;
+}
+
+// Micro-benchmark for Charmap::contains.
+void BM_Contains(benchmark::State& state) {
+ // Loop-body replicated 10 times to increase time per iteration.
+ // Argument continuously changed to avoid generating common subexpressions.
+ const absl::strings_internal::Charmap benchmark_map = MakeBenchmarkMap();
+ unsigned char c = 0;
+ int ops = 0;
+ for (auto _ : state) {
+ ops += benchmark_map.contains(c++);
+ ops += benchmark_map.contains(c++);
+ ops += benchmark_map.contains(c++);
+ ops += benchmark_map.contains(c++);
+ ops += benchmark_map.contains(c++);
+ ops += benchmark_map.contains(c++);
+ ops += benchmark_map.contains(c++);
+ ops += benchmark_map.contains(c++);
+ ops += benchmark_map.contains(c++);
+ ops += benchmark_map.contains(c++);
+ }
+ benchmark::DoNotOptimize(ops);
+}
+BENCHMARK(BM_Contains);
+
+// We don't bother benchmarking Charmap::IsZero or Charmap::IntersectsWith;
+// their running time is data-dependent and it is not worth characterizing
+// "typical" data.
+
+} // namespace