Export of internal Abseil changes.

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906c47420646d510edd2479d5542c56f5fa31b65 by CJ Johnson <johnsoncj@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 216573923

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74560d4afd2b605909e677c6fc3076049fb3010a by Eric Fiselier <ericwf@google.com>:

Avoid -Wformat-pedantic in benchmark.

PiperOrigin-RevId: 216523769

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9bcc9da8b03e6d1ea43ee78931256c5541cb9686 by Eric Fiselier <ericwf@google.com>:

Delete unused CityHash functions.

PiperOrigin-RevId: 216464492

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a42563b394c89fbb4c55cb5a6a5edbf96d271eea by Abseil Team <absl-team@google.com>:

Introduce new Abseil interfaces for converting between civil
times and absolute times.s

Deprecates absl::ConvertDateTime() and absl::FromDateTime().

PiperOrigin-RevId: 216424948

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088e11235124267517d7f137854fa5554679c24f by Eric Fiselier <ericwf@google.com>:

Remove unneeded break statements in test.

PiperOrigin-RevId: 216403321
GitOrigin-RevId: 906c47420646d510edd2479d5542c56f5fa31b65
Change-Id: Idb44420be623e369c66f5a9c92bdc9ab46d3ec92

1 files changed, 57 insertions, 0 deletions

diff --git a/absl/time/civil_time_benchmark.cc b/absl/time/civil_time_benchmark.cc
new file mode 100644
index 00000000..567c2a33
--- /dev/null
+++ b/absl/time/civil_time_benchmark.cc
@@ -0,0 +1,57 @@
+// 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/time/civil_time.h"
+
+#include "benchmark/benchmark.h"
+
+namespace {
+
+// Benchmark                            Time(ns)       CPU(ns)    Iterations
+// -------------------------------------------------------------------------
+// BM_Difference_Days                         20            20      34542508
+// BM_Step_Days                               15            15      48098146
+// BM_Format                                 688           687       1019803
+// BM_Parse                                  921           920        762788
+// BM_RoundTripFormatParse                  1766          1764        396092
+
+void BM_Difference_Days(benchmark::State& state) {
+  const absl::CivilDay c(2014, 8, 22);
+  const absl::CivilDay epoch(1970, 1, 1);
+  while (state.KeepRunning()) {
+    const absl::civil_diff_t n = c - epoch;
+    benchmark::DoNotOptimize(n);
+  }
+}
+BENCHMARK(BM_Difference_Days);
+
+void BM_Step_Days(benchmark::State& state) {
+  const absl::CivilDay kStart(2014, 8, 22);
+  absl::CivilDay c = kStart;
+  while (state.KeepRunning()) {
+    benchmark::DoNotOptimize(++c);
+  }
+}
+BENCHMARK(BM_Step_Days);
+
+void BM_Format(benchmark::State& state) {
+  const absl::CivilSecond c(2014, 1, 2, 3, 4, 5);
+  while (state.KeepRunning()) {
+    const std::string s = absl::FormatCivilTime(c);
+    benchmark::DoNotOptimize(s);
+  }
+}
+BENCHMARK(BM_Format);
+
+}  // namespace