- a4e14440b870dbf7b36975eaebf783a70a7fcee4 Release string_view microbenchmarks. by Alex Strelnikov <strel@google.com>

  - 7cec68e37e16fb4e266368236ae1de6419f6946a Increase Abseil's minimum supported cmake version to 3.1.... by Jon Cohen <cohenjon@google.com>
  - b977456175c8db380676bd56c44b32efbfc6f606 Fix a typo in the mutex.h comments. by Abseil Team <absl-team@google.com>
  - 3d30cec131d08b066bc1cf877e4f661e8ee0584c Release StrSplit microbenchmarks. by Alex Strelnikov <strel@google.com>
  - dddece6031feac1cca4689e623462f895f28d019 Release StrReplace microbenchmarks. by Alex Strelnikov <strel@google.com>
  - ac3b40e1694f74bdcf31b8d1152481e92edfd441 Internal Change by Abseil Team <absl-team@google.com>
  - d0e69ad6ddf0e59596a02ccab0253967f2909cdb Release StrCat microbenchmarks. by Alex Strelnikov <strel@google.com>
  - db4d471030fa320d2b9d2ce241610333f0eb7a50 Release StrJoin microbenchmarks. by Alex Strelnikov <strel@google.com>

GitOrigin-RevId: a4e14440b870dbf7b36975eaebf783a70a7fcee4
Change-Id: I3f12700aafce677049f4d1a6e09ea821963a8c9e

1 files changed, 158 insertions, 0 deletions

diff --git a/absl/strings/str_split_benchmark.cc b/absl/strings/str_split_benchmark.cc
new file mode 100644
index 0000000..c35787b
--- /dev/null
+++ b/absl/strings/str_split_benchmark.cc
@@ -0,0 +1,158 @@
+// Copyright 2018 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/str_split.h"
+
+#include <iterator>
+#include <string>
+#include <unordered_map>
+#include <unordered_set>
+#include <vector>
+
+#include "benchmark/benchmark.h"
+#include "absl/base/internal/raw_logging.h"
+#include "absl/strings/string_view.h"
+
+namespace {
+
+std::string MakeTestString(int desired_length) {
+  static const int kAverageValueLen = 25;
+  std::string test(desired_length * kAverageValueLen, 'x');
+  for (int i = 1; i < test.size(); i += kAverageValueLen) {
+    test[i] = ';';
+  }
+  return test;
+}
+
+void BM_Split2StringPiece(benchmark::State& state) {
+  std::string test = MakeTestString(state.range(0));
+  for (auto _ : state) {
+    std::vector<absl::string_view> result = absl::StrSplit(test, ';');
+    benchmark::DoNotOptimize(result);
+  }
+}
+BENCHMARK_RANGE(BM_Split2StringPiece, 0, 1 << 20);
+
+void BM_Split2StringPieceLifted(benchmark::State& state) {
+  std::string test = MakeTestString(state.range(0));
+  std::vector<absl::string_view> result;
+  for (auto _ : state) {
+    result = absl::StrSplit(test, ';');
+  }
+  benchmark::DoNotOptimize(result);
+}
+BENCHMARK_RANGE(BM_Split2StringPieceLifted, 0, 1 << 20);
+
+void BM_Split2String(benchmark::State& state) {
+  std::string test = MakeTestString(state.range(0));
+  for (auto _ : state) {
+    std::vector<std::string> result = absl::StrSplit(test, ';');
+    benchmark::DoNotOptimize(result);
+  }
+}
+BENCHMARK_RANGE(BM_Split2String, 0, 1 << 20);
+
+// This benchmark is for comparing Split2 to Split1 (SplitStringUsing). In
+// particular, this benchmark uses SkipEmpty() to match SplitStringUsing's
+// behavior.
+void BM_Split2SplitStringUsing(benchmark::State& state) {
+  std::string test = MakeTestString(state.range(0));
+  for (auto _ : state) {
+    std::vector<std::string> result = absl::StrSplit(test, ';', absl::SkipEmpty());
+    benchmark::DoNotOptimize(result);
+  }
+}
+BENCHMARK_RANGE(BM_Split2SplitStringUsing, 0, 1 << 20);
+
+void BM_SplitStringToUnorderedSet(benchmark::State& state) {
+  const int len = state.range(0);
+  std::string test(len, 'x');
+  for (int i = 1; i < len; i += 2) {
+    test[i] = ';';
+  }
+  for (auto _ : state) {
+    std::unordered_set<std::string> result =
+        absl::StrSplit(test, ':', absl::SkipEmpty());
+    benchmark::DoNotOptimize(result);
+  }
+}
+BENCHMARK_RANGE(BM_SplitStringToUnorderedSet, 0, 1 << 20);
+
+void BM_SplitStringToUnorderedMap(benchmark::State& state) {
+  const int len = state.range(0);
+  std::string test(len, 'x');
+  for (int i = 1; i < len; i += 2) {
+    test[i] = ';';
+  }
+  for (auto _ : state) {
+    std::unordered_map<std::string, std::string> result =
+        absl::StrSplit(test, ':', absl::SkipEmpty());
+    benchmark::DoNotOptimize(result);
+  }
+}
+BENCHMARK_RANGE(BM_SplitStringToUnorderedMap, 0, 1 << 20);
+
+void BM_SplitStringAllowEmpty(benchmark::State& state) {
+  const int len = state.range(0);
+  std::string test(len, 'x');
+  for (int i = 1; i < len; i += 2) {
+    test[i] = ';';
+  }
+  for (auto _ : state) {
+    std::vector<std::string> result = absl::StrSplit(test, ';');
+    benchmark::DoNotOptimize(result);
+  }
+}
+BENCHMARK_RANGE(BM_SplitStringAllowEmpty, 0, 1 << 20);
+
+struct OneCharLiteral {
+  char operator()() const { return 'X'; }
+};
+
+struct OneCharStringLiteral {
+  const char* operator()() const { return "X"; }
+};
+
+template <typename DelimiterFactory>
+void BM_SplitStringWithOneChar(benchmark::State& state) {
+  const auto delimiter = DelimiterFactory()();
+  std::vector<absl::string_view> pieces;
+  size_t v = 0;
+  for (auto _ : state) {
+    pieces = absl::StrSplit("The quick brown fox jumps over the lazy dog",
+                            delimiter);
+    v += pieces.size();
+  }
+  ABSL_RAW_CHECK(v == state.iterations(), "");
+}
+BENCHMARK_TEMPLATE(BM_SplitStringWithOneChar, OneCharLiteral);
+BENCHMARK_TEMPLATE(BM_SplitStringWithOneChar, OneCharStringLiteral);
+
+template <typename DelimiterFactory>
+void BM_SplitStringWithOneCharNoVector(benchmark::State& state) {
+  const auto delimiter = DelimiterFactory()();
+  size_t v = 0;
+  for (auto _ : state) {
+    auto splitter = absl::StrSplit(
+        "The quick brown fox jumps over the lazy dog", delimiter);
+    v += std::distance(splitter.begin(), splitter.end());
+  }
+  ABSL_RAW_CHECK(v == state.iterations(), "");
+}
+BENCHMARK_TEMPLATE(BM_SplitStringWithOneCharNoVector, OneCharLiteral);
+BENCHMARK_TEMPLATE(BM_SplitStringWithOneCharNoVector, OneCharStringLiteral);
+
+}  // namespace
+
+BENCHMARK_MAIN();