BASELINE: Update Chromium to 71.0.3578.93

Change-Id: I6a32086c33670e1b033f8b10e6bf1fd4da1d105d
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

1 files changed, 119 insertions, 0 deletions

diff --git a/chromium/base/observer_list_perftest.cc b/chromium/base/observer_list_perftest.cc
new file mode 100644
index 00000000000..2e0e5e88c00
--- /dev/null
+++ b/chromium/base/observer_list_perftest.cc
@@ -0,0 +1,119 @@
+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/observer_list.h"
+
+#include <memory>
+
+#include "base/logging.h"
+#include "base/observer_list.h"
+#include "base/strings/stringprintf.h"
+#include "base/time/time.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/perf/perf_test.h"
+
+// Ask the compiler not to use a register for this counter, in case it decides
+// to do magic optimizations like |counter += kLaps|.
+volatile int g_observer_list_perf_test_counter;
+
+namespace base {
+
+class ObserverInterface {
+ public:
+  ObserverInterface() {}
+  virtual ~ObserverInterface() {}
+  virtual void Observe() const { ++g_observer_list_perf_test_counter; }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ObserverInterface);
+};
+
+class UnsafeObserver : public ObserverInterface {};
+
+class TestCheckedObserver : public CheckedObserver, public ObserverInterface {};
+
+template <class ObserverType>
+struct Pick {
+  // The ObserverList type to use. Checked observers need to be in a checked
+  // ObserverList.
+  using ObserverListType = ObserverList<ObserverType>;
+  static const char* GetName() { return "CheckedObserver"; }
+};
+template <>
+struct Pick<UnsafeObserver> {
+  using ObserverListType = ObserverList<ObserverInterface>::Unchecked;
+  static const char* GetName() { return "UnsafeObserver"; }
+};
+
+template <class ObserverType>
+class ObserverListPerfTest : public ::testing::Test {
+ public:
+  using ObserverListType = typename Pick<ObserverType>::ObserverListType;
+
+  ObserverListPerfTest() {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ObserverListPerfTest);
+};
+
+typedef ::testing::Types<UnsafeObserver, TestCheckedObserver> ObserverTypes;
+TYPED_TEST_CASE(ObserverListPerfTest, ObserverTypes);
+
+// Performance test for base::ObserverList and Checked Observers.
+TYPED_TEST(ObserverListPerfTest, NotifyPerformance) {
+  constexpr int kMaxObservers = 128;
+#if DCHECK_IS_ON()
+  // The test takes about 100x longer in debug builds, mostly due to sequence
+  // checker overheads when WeakPtr gets involved.
+  constexpr int kLaps = 1000000;
+#else
+  constexpr int kLaps = 100000000;
+#endif
+  constexpr int kWarmupLaps = 100;
+  std::vector<std::unique_ptr<TypeParam>> observers;
+
+  for (int observer_count = 0; observer_count <= kMaxObservers;
+       observer_count = observer_count ? observer_count * 2 : 1) {
+    typename TestFixture::ObserverListType list;
+    for (int i = 0; i < observer_count; ++i)
+      observers.push_back(std::make_unique<TypeParam>());
+    for (auto& o : observers)
+      list.AddObserver(o.get());
+
+    for (int i = 0; i < kWarmupLaps; ++i) {
+      for (auto& o : list)
+        o.Observe();
+    }
+    g_observer_list_perf_test_counter = 0;
+    const int weighted_laps = kLaps / (observer_count + 1);
+
+    TimeTicks start = TimeTicks::Now();
+    for (int i = 0; i < weighted_laps; ++i) {
+      for (auto& o : list)
+        o.Observe();
+    }
+    TimeDelta duration = TimeTicks::Now() - start;
+
+    const char* name = Pick<TypeParam>::GetName();
+    observers.clear();
+
+    EXPECT_EQ(observer_count * weighted_laps,
+              g_observer_list_perf_test_counter);
+    EXPECT_TRUE(observer_count == 0 || list.might_have_observers());
+
+    std::string prefix =
+        base::StringPrintf("ObserverListPerfTest_%d.", observer_count);
+
+    // A typical value is 3-20 nanoseconds per observe in Release, 1000-2000ns
+    // in an optimized build with DCHECKs and 3000-6000ns in debug builds.
+    perf_test::PrintResult(
+        prefix, name, "NotifyPerformance",
+        duration.InNanoseconds() /
+            static_cast<double>(g_observer_list_perf_test_counter +
+                                weighted_laps),
+        "ns/observe", true);
+  }
+}
+
+}  // namespace base