Export of internal Abseil changes

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f8fe0f483378c7520d8f8bdfabe4b20de4d96c7e by Andy Soffer <asoffer@google.com>:

Ensure that Invoke can support C++17 in the sense that noexcept is part of the type.

PiperOrigin-RevId: 261730155

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bf796ab71653a80498f9374bc8c5111d065c64ba by Abseil Team <absl-team@google.com>:

Fix typo in static_assert message for copy/move constructible by replacing "by" with "be".

PiperOrigin-RevId: 261713992

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8c7c17c40d03a322f304a2fd73ed34462dbf265a by Andy Soffer <asoffer@google.com>:

Add absl::is_function drop-in replacement for std::is_function. Some standard
libraries incorrectly implement std::is_function in a few corner cases. In
particular, libstdc++ functions marked noexcept.

The trick being used here is that function types decay to pointers. After
excluding cases like is_class, etc, we can distinguish function types by
testing for this decay.

Many thanks to ericwf@ for essentially writing this CL.

PiperOrigin-RevId: 261705008

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c5adf42d0a132c2525d17a719329eab2ffe0aa94 by Abseil Team <absl-team@google.com>:

Add microbenchmark for StrSplit that uses delimiter ByAnyChar.

PiperOrigin-RevId: 261424010

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66a342f9381ec56be2fe3aa5b3193dd3538a9740 by Andy Soffer <asoffer@google.com>:

CMake support for Abseil Random

This change touches almost build-related files for CMake almost exclusively. The one minor exception is random/internal/salted_seed_seq.h. The default warnings configuration for one of our CI builds requests not having named but unused parameters. The change in this file cleans up that warning.

PiperOrigin-RevId: 261192369
GitOrigin-RevId: f8fe0f483378c7520d8f8bdfabe4b20de4d96c7e
Change-Id: I05f662baacfe78750651535aa658f61c2327bc44

1 files changed, 23 insertions, 0 deletions

diff --git a/absl/strings/str_split_benchmark.cc b/absl/strings/str_split_benchmark.cc
index 28c25e8d354b..f38dfcfe5af7 100644
--- a/absl/strings/str_split_benchmark.cc
+++ b/absl/strings/str_split_benchmark.cc
@@ -44,6 +44,29 @@ void BM_Split2StringView(benchmark::State& state) {
 }
 BENCHMARK_RANGE(BM_Split2StringView, 0, 1 << 20);
 
+static const absl::string_view kDelimiters = ";:,.";
+
+std::string MakeMultiDelimiterTestString(int desired_length) {
+  static const int kAverageValueLen = 25;
+  std::string test(desired_length * kAverageValueLen, 'x');
+  for (int i = 0; i * kAverageValueLen < test.size(); ++i) {
+    // Cycle through a variety of delimiters.
+    test[i * kAverageValueLen] = kDelimiters[i % kDelimiters.size()];
+  }
+  return test;
+}
+
+// Measure StrSplit with ByAnyChar with four delimiters to choose from.
+void BM_Split2StringViewByAnyChar(benchmark::State& state) {
+  std::string test = MakeMultiDelimiterTestString(state.range(0));
+  for (auto _ : state) {
+    std::vector<absl::string_view> result =
+        absl::StrSplit(test, absl::ByAnyChar(kDelimiters));
+    benchmark::DoNotOptimize(result);
+  }
+}
+BENCHMARK_RANGE(BM_Split2StringViewByAnyChar, 0, 1 << 20);
+
 void BM_Split2StringViewLifted(benchmark::State& state) {
   std::string test = MakeTestString(state.range(0));
   std::vector<absl::string_view> result;