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authorVincent Ambo <mail@tazj.in>2022-02-07T23·05+0300
committerclbot <clbot@tvl.fyi>2022-02-07T23·09+0000
commit5aa5d282eac56a21e74611c1cdbaa97bb5db2dca (patch)
tree8cc5dce8157a1470ff76719dd15d65f648a05522 /third_party/abseil_cpp/absl/strings/string_view_benchmark.cc
parenta25675804c4f429fab5ee5201fe25e89865dfd13 (diff)
chore(3p/abseil_cpp): unvendor abseil_cpp r/3786
we weren't actually using these sources anymore, okay?

Change-Id: If701571d9716de308d3512e1eb22c35db0877a66
Reviewed-on: https://cl.tvl.fyi/c/depot/+/5248
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Diffstat (limited to 'third_party/abseil_cpp/absl/strings/string_view_benchmark.cc')
-rw-r--r--third_party/abseil_cpp/absl/strings/string_view_benchmark.cc381
1 files changed, 0 insertions, 381 deletions
diff --git a/third_party/abseil_cpp/absl/strings/string_view_benchmark.cc b/third_party/abseil_cpp/absl/strings/string_view_benchmark.cc
deleted file mode 100644
index 0d74e23e2fc9..000000000000
--- a/third_party/abseil_cpp/absl/strings/string_view_benchmark.cc
+++ /dev/null
@@ -1,381 +0,0 @@
-// 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
-//
-//      https://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/string_view.h"
-
-#include <algorithm>
-#include <cstdint>
-#include <map>
-#include <random>
-#include <string>
-#include <unordered_set>
-#include <vector>
-
-#include "benchmark/benchmark.h"
-#include "absl/base/attributes.h"
-#include "absl/base/internal/raw_logging.h"
-#include "absl/base/macros.h"
-#include "absl/strings/str_cat.h"
-
-namespace {
-
-void BM_StringViewFromString(benchmark::State& state) {
-  std::string s(state.range(0), 'x');
-  std::string* ps = &s;
-  struct SV {
-    SV() = default;
-    explicit SV(const std::string& s) : sv(s) {}
-    absl::string_view sv;
-  } sv;
-  SV* psv = &sv;
-  benchmark::DoNotOptimize(ps);
-  benchmark::DoNotOptimize(psv);
-  for (auto _ : state) {
-    new (psv) SV(*ps);
-    benchmark::DoNotOptimize(sv);
-  }
-}
-BENCHMARK(BM_StringViewFromString)->Arg(12)->Arg(128);
-
-// Provide a forcibly out-of-line wrapper for operator== that can be used in
-// benchmarks to measure the impact of inlining.
-ABSL_ATTRIBUTE_NOINLINE
-bool NonInlinedEq(absl::string_view a, absl::string_view b) { return a == b; }
-
-// We use functions that cannot be inlined to perform the comparison loops so
-// that inlining of the operator== can't optimize away *everything*.
-ABSL_ATTRIBUTE_NOINLINE
-void DoEqualityComparisons(benchmark::State& state, absl::string_view a,
-                           absl::string_view b) {
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(a == b);
-  }
-}
-
-void BM_EqualIdentical(benchmark::State& state) {
-  std::string x(state.range(0), 'a');
-  DoEqualityComparisons(state, x, x);
-}
-BENCHMARK(BM_EqualIdentical)->DenseRange(0, 3)->Range(4, 1 << 10);
-
-void BM_EqualSame(benchmark::State& state) {
-  std::string x(state.range(0), 'a');
-  std::string y = x;
-  DoEqualityComparisons(state, x, y);
-}
-BENCHMARK(BM_EqualSame)
-    ->DenseRange(0, 10)
-    ->Arg(20)
-    ->Arg(40)
-    ->Arg(70)
-    ->Arg(110)
-    ->Range(160, 4096);
-
-void BM_EqualDifferent(benchmark::State& state) {
-  const int len = state.range(0);
-  std::string x(len, 'a');
-  std::string y = x;
-  if (len > 0) {
-    y[len - 1] = 'b';
-  }
-  DoEqualityComparisons(state, x, y);
-}
-BENCHMARK(BM_EqualDifferent)->DenseRange(0, 3)->Range(4, 1 << 10);
-
-// This benchmark is intended to check that important simplifications can be
-// made with absl::string_view comparisons against constant strings. The idea is
-// that if constant strings cause redundant components of the comparison, the
-// compiler should detect and eliminate them. Here we use 8 different strings,
-// each with the same size. Provided our comparison makes the implementation
-// inline-able by the compiler, it should fold all of these away into a single
-// size check once per loop iteration.
-ABSL_ATTRIBUTE_NOINLINE
-void DoConstantSizeInlinedEqualityComparisons(benchmark::State& state,
-                                              absl::string_view a) {
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(a == "aaa");
-    benchmark::DoNotOptimize(a == "bbb");
-    benchmark::DoNotOptimize(a == "ccc");
-    benchmark::DoNotOptimize(a == "ddd");
-    benchmark::DoNotOptimize(a == "eee");
-    benchmark::DoNotOptimize(a == "fff");
-    benchmark::DoNotOptimize(a == "ggg");
-    benchmark::DoNotOptimize(a == "hhh");
-  }
-}
-void BM_EqualConstantSizeInlined(benchmark::State& state) {
-  std::string x(state.range(0), 'a');
-  DoConstantSizeInlinedEqualityComparisons(state, x);
-}
-// We only need to check for size of 3, and <> 3 as this benchmark only has to
-// do with size differences.
-BENCHMARK(BM_EqualConstantSizeInlined)->DenseRange(2, 4);
-
-// This benchmark exists purely to give context to the above timings: this is
-// what they would look like if the compiler is completely unable to simplify
-// between two comparisons when they are comparing against constant strings.
-ABSL_ATTRIBUTE_NOINLINE
-void DoConstantSizeNonInlinedEqualityComparisons(benchmark::State& state,
-                                                 absl::string_view a) {
-  for (auto _ : state) {
-    // Force these out-of-line to compare with the above function.
-    benchmark::DoNotOptimize(NonInlinedEq(a, "aaa"));
-    benchmark::DoNotOptimize(NonInlinedEq(a, "bbb"));
-    benchmark::DoNotOptimize(NonInlinedEq(a, "ccc"));
-    benchmark::DoNotOptimize(NonInlinedEq(a, "ddd"));
-    benchmark::DoNotOptimize(NonInlinedEq(a, "eee"));
-    benchmark::DoNotOptimize(NonInlinedEq(a, "fff"));
-    benchmark::DoNotOptimize(NonInlinedEq(a, "ggg"));
-    benchmark::DoNotOptimize(NonInlinedEq(a, "hhh"));
-  }
-}
-
-void BM_EqualConstantSizeNonInlined(benchmark::State& state) {
-  std::string x(state.range(0), 'a');
-  DoConstantSizeNonInlinedEqualityComparisons(state, x);
-}
-// We only need to check for size of 3, and <> 3 as this benchmark only has to
-// do with size differences.
-BENCHMARK(BM_EqualConstantSizeNonInlined)->DenseRange(2, 4);
-
-void BM_CompareSame(benchmark::State& state) {
-  const int len = state.range(0);
-  std::string x;
-  for (int i = 0; i < len; i++) {
-    x += 'a';
-  }
-  std::string y = x;
-  absl::string_view a = x;
-  absl::string_view b = y;
-
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(a);
-    benchmark::DoNotOptimize(b);
-    benchmark::DoNotOptimize(a.compare(b));
-  }
-}
-BENCHMARK(BM_CompareSame)->DenseRange(0, 3)->Range(4, 1 << 10);
-
-void BM_CompareFirstOneLess(benchmark::State& state) {
-  const int len = state.range(0);
-  std::string x(len, 'a');
-  std::string y = x;
-  y.back() = 'b';
-  absl::string_view a = x;
-  absl::string_view b = y;
-
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(a);
-    benchmark::DoNotOptimize(b);
-    benchmark::DoNotOptimize(a.compare(b));
-  }
-}
-BENCHMARK(BM_CompareFirstOneLess)->DenseRange(1, 3)->Range(4, 1 << 10);
-
-void BM_CompareSecondOneLess(benchmark::State& state) {
-  const int len = state.range(0);
-  std::string x(len, 'a');
-  std::string y = x;
-  x.back() = 'b';
-  absl::string_view a = x;
-  absl::string_view b = y;
-
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(a);
-    benchmark::DoNotOptimize(b);
-    benchmark::DoNotOptimize(a.compare(b));
-  }
-}
-BENCHMARK(BM_CompareSecondOneLess)->DenseRange(1, 3)->Range(4, 1 << 10);
-
-void BM_find_string_view_len_one(benchmark::State& state) {
-  std::string haystack(state.range(0), '0');
-  absl::string_view s(haystack);
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(s.find("x"));  // not present; length 1
-  }
-}
-BENCHMARK(BM_find_string_view_len_one)->Range(1, 1 << 20);
-
-void BM_find_string_view_len_two(benchmark::State& state) {
-  std::string haystack(state.range(0), '0');
-  absl::string_view s(haystack);
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(s.find("xx"));  // not present; length 2
-  }
-}
-BENCHMARK(BM_find_string_view_len_two)->Range(1, 1 << 20);
-
-void BM_find_one_char(benchmark::State& state) {
-  std::string haystack(state.range(0), '0');
-  absl::string_view s(haystack);
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(s.find('x'));  // not present
-  }
-}
-BENCHMARK(BM_find_one_char)->Range(1, 1 << 20);
-
-void BM_rfind_one_char(benchmark::State& state) {
-  std::string haystack(state.range(0), '0');
-  absl::string_view s(haystack);
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(s.rfind('x'));  // not present
-  }
-}
-BENCHMARK(BM_rfind_one_char)->Range(1, 1 << 20);
-
-void BM_worst_case_find_first_of(benchmark::State& state, int haystack_len) {
-  const int needle_len = state.range(0);
-  std::string needle;
-  for (int i = 0; i < needle_len; ++i) {
-    needle += 'a' + i;
-  }
-  std::string haystack(haystack_len, '0');  // 1000 zeros.
-
-  absl::string_view s(haystack);
-  for (auto _ : state) {
-    benchmark::DoNotOptimize(s.find_first_of(needle));
-  }
-}
-
-void BM_find_first_of_short(benchmark::State& state) {
-  BM_worst_case_find_first_of(state, 10);
-}
-
-void BM_find_first_of_medium(benchmark::State& state) {
-  BM_worst_case_find_first_of(state, 100);
-}
-
-void BM_find_first_of_long(benchmark::State& state) {
-  BM_worst_case_find_first_of(state, 1000);
-}
-
-BENCHMARK(BM_find_first_of_short)->DenseRange(0, 4)->Arg(8)->Arg(16)->Arg(32);
-BENCHMARK(BM_find_first_of_medium)->DenseRange(0, 4)->Arg(8)->Arg(16)->Arg(32);
-BENCHMARK(BM_find_first_of_long)->DenseRange(0, 4)->Arg(8)->Arg(16)->Arg(32);
-
-struct EasyMap : public std::map<absl::string_view, uint64_t> {
-  explicit EasyMap(size_t) {}
-};
-
-// This templated benchmark helper function is intended to stress operator== or
-// operator< in a realistic test.  It surely isn't entirely realistic, but it's
-// a start.  The test creates a map of type Map, a template arg, and populates
-// it with table_size key/value pairs. Each key has WordsPerKey words.  After
-// creating the map, a number of lookups are done in random order.  Some keys
-// are used much more frequently than others in this phase of the test.
-template <typename Map, int WordsPerKey>
-void StringViewMapBenchmark(benchmark::State& state) {
-  const int table_size = state.range(0);
-  const double kFractionOfKeysThatAreHot = 0.2;
-  const int kNumLookupsOfHotKeys = 20;
-  const int kNumLookupsOfColdKeys = 1;
-  const char* words[] = {"the",   "quick",  "brown",    "fox",      "jumped",
-                         "over",  "the",    "lazy",     "dog",      "and",
-                         "found", "a",      "large",    "mushroom", "and",
-                         "a",     "couple", "crickets", "eating",   "pie"};
-  // Create some keys that consist of words in random order.
-  std::random_device r;
-  std::seed_seq seed({r(), r(), r(), r(), r(), r(), r(), r()});
-  std::mt19937 rng(seed);
-  std::vector<std::string> keys(table_size);
-  std::vector<int> all_indices;
-  const int kBlockSize = 1 << 12;
-  std::unordered_set<std::string> t(kBlockSize);
-  std::uniform_int_distribution<int> uniform(0, ABSL_ARRAYSIZE(words) - 1);
-  for (int i = 0; i < table_size; i++) {
-    all_indices.push_back(i);
-    do {
-      keys[i].clear();
-      for (int j = 0; j < WordsPerKey; j++) {
-        absl::StrAppend(&keys[i], j > 0 ? " " : "", words[uniform(rng)]);
-      }
-    } while (!t.insert(keys[i]).second);
-  }
-
-  // Create a list of strings to lookup: a permutation of the array of
-  // keys we just created, with repeats.  "Hot" keys get repeated more.
-  std::shuffle(all_indices.begin(), all_indices.end(), rng);
-  const int num_hot = table_size * kFractionOfKeysThatAreHot;
-  const int num_cold = table_size - num_hot;
-  std::vector<int> hot_indices(all_indices.begin(),
-                               all_indices.begin() + num_hot);
-  std::vector<int> indices;
-  for (int i = 0; i < kNumLookupsOfColdKeys; i++) {
-    indices.insert(indices.end(), all_indices.begin(), all_indices.end());
-  }
-  for (int i = 0; i < kNumLookupsOfHotKeys - kNumLookupsOfColdKeys; i++) {
-    indices.insert(indices.end(), hot_indices.begin(), hot_indices.end());
-  }
-  std::shuffle(indices.begin(), indices.end(), rng);
-  ABSL_RAW_CHECK(
-      num_cold * kNumLookupsOfColdKeys + num_hot * kNumLookupsOfHotKeys ==
-          indices.size(),
-      "");
-  // After constructing the array we probe it with absl::string_views built from
-  // test_strings.  This means operator== won't see equal pointers, so
-  // it'll have to check for equal lengths and equal characters.
-  std::vector<std::string> test_strings(indices.size());
-  for (int i = 0; i < indices.size(); i++) {
-    test_strings[i] = keys[indices[i]];
-  }
-
-  // Run the benchmark. It includes map construction but is mostly
-  // map lookups.
-  for (auto _ : state) {
-    Map h(table_size);
-    for (int i = 0; i < table_size; i++) {
-      h[keys[i]] = i * 2;
-    }
-    ABSL_RAW_CHECK(h.size() == table_size, "");
-    uint64_t sum = 0;
-    for (int i = 0; i < indices.size(); i++) {
-      sum += h[test_strings[i]];
-    }
-    benchmark::DoNotOptimize(sum);
-  }
-}
-
-void BM_StdMap_4(benchmark::State& state) {
-  StringViewMapBenchmark<EasyMap, 4>(state);
-}
-BENCHMARK(BM_StdMap_4)->Range(1 << 10, 1 << 16);
-
-void BM_StdMap_8(benchmark::State& state) {
-  StringViewMapBenchmark<EasyMap, 8>(state);
-}
-BENCHMARK(BM_StdMap_8)->Range(1 << 10, 1 << 16);
-
-void BM_CopyToStringNative(benchmark::State& state) {
-  std::string src(state.range(0), 'x');
-  absl::string_view sv(src);
-  std::string dst;
-  for (auto _ : state) {
-    dst.assign(sv.begin(), sv.end());
-  }
-}
-BENCHMARK(BM_CopyToStringNative)->Range(1 << 3, 1 << 12);
-
-void BM_AppendToStringNative(benchmark::State& state) {
-  std::string src(state.range(0), 'x');
-  absl::string_view sv(src);
-  std::string dst;
-  for (auto _ : state) {
-    dst.clear();
-    dst.insert(dst.end(), sv.begin(), sv.end());
-  }
-}
-BENCHMARK(BM_AppendToStringNative)->Range(1 << 3, 1 << 12);
-
-}  // namespace