Make a benchmark out of tst_QObjectPerformance::emitToManyReceivers

The test has been flaky on top of QEMU. The test is clearly a sort of manually
rolled benchmark, not a regular autotest. Remove the test and replace it with a
benchmark in QObjectBenchmark.

Task-number: QTBUG-66823
Task-number: QTBUG-66216
Change-Id: I7a48293023f32141eed6fea50fbb63af18933a8f
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/tests/benchmarks/corelib/kernel/qobject/main.cpp b/tests/benchmarks/corelib/kernel/qobject/main.cpp
index c11b13b7ea..04ca69ad3b 100644
--- a/tests/benchmarks/corelib/kernel/qobject/main.cpp
+++ b/tests/benchmarks/corelib/kernel/qobject/main.cpp
@@ -43,6 +43,8 @@ Q_OBJECT
 private slots:
     void signal_slot_benchmark();
     void signal_slot_benchmark_data();
+    void signal_many_receivers();
+    void signal_many_receivers_data();
     void qproperty_benchmark_data();
     void qproperty_benchmark();
     void dynamic_property_benchmark();
@@ -127,6 +129,28 @@ void QObjectBenchmark::signal_slot_benchmark()
     }
 }
 
+void QObjectBenchmark::signal_many_receivers_data()
+{
+    QTest::addColumn<int>("receiverCount");
+    QTest::newRow("100 receivers") << 100;
+    QTest::newRow("1 000 receivers") << 1000;
+    QTest::newRow("10 000 receivers") << 10000;
+}
+
+void QObjectBenchmark::signal_many_receivers()
+{
+    QFETCH(int, receiverCount);
+    Object sender;
+    std::vector<Object> receivers(receiverCount);
+
+    for (Object &receiver : receivers)
+        QObject::connect(&sender, &Object::signal0, &receiver, &Object::slot0);
+
+    QBENCHMARK {
+        sender.emitSignal0();
+    }
+}
+
 void QObjectBenchmark::qproperty_benchmark_data()
 {
     QTest::addColumn<QByteArray>("name");