tst_tostring: add benchmarks for QCOMPARE vs. QCOMPARE_EQ

There's currently no statistically-significant difference between the
two, due to a huge pessimistion in QTestLib where every QCOMPARE* and
QVERIFY writes 1KiB of data onto the stack before doing anything else,
so I'm not reporting numbers in this commit message.

Pick-to: 6.4
Task-number: QTBUG-98873
Task-number: QTBUG-98874
Change-Id: I233878596f0a8fe6b96360adb839fecd72c398a2
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

1 files changed, 55 insertions, 0 deletions

diff --git a/tests/benchmarks/testlib/tostring/tst_tostring.cpp b/tests/benchmarks/testlib/tostring/tst_tostring.cpp
index 913a0337c6..c72ec220b1 100644
--- a/tests/benchmarks/testlib/tostring/tst_tostring.cpp
+++ b/tests/benchmarks/testlib/tostring/tst_tostring.cpp
@@ -25,6 +25,36 @@ private slots:
     void quint64Tst() { numeric<quint64>(); }
     void qint64Tst_data() { numeric_data<qint64>(); }
     void qint64Tst() { numeric<qint64>(); }
+
+private:
+    template <typename T> void compare();
+    template <typename T> void compare_eq();
+
+private slots:
+    void floatCompare_data() { numeric_data<float>(); }
+    void floatCompare() { compare<float>(); }
+    void floatCompareEq_data() { numeric_data<float>(); }
+    void floatCompareEq() { compare_eq<float>(); }
+    void doubleCompare_data() { numeric_data<double>(); }
+    void doubleCompare() { compare<double>(); }
+    void doubleCompareEq_data() { numeric_data<double>(); }
+    void doubleCompareEq() { compare_eq<double>(); }
+    void intCompare_data() { numeric_data<int>(); }
+    void intCompare() { compare<int>(); }
+    void intCompareEq_data() { numeric_data<int>(); }
+    void intCompareEq() { compare_eq<int>(); }
+    void unsignedCompare_data() { numeric_data<unsigned>(); }
+    void unsignedCompare() { compare<unsigned>(); }
+    void unsignedCompareEq_data() { numeric_data<unsigned>(); }
+    void unsignedCompareEq() { compare_eq<unsigned>(); }
+    void quint64Compare_data() { numeric_data<quint64>(); }
+    void quint64Compare() { compare<quint64>(); }
+    void quint64CompareEq_data() { numeric_data<quint64>(); }
+    void quint64CompareEq() { compare_eq<quint64>(); }
+    void qint64Compare_data() { numeric_data<qint64>(); }
+    void qint64Compare() { compare<qint64>(); }
+    void qint64CompareEq_data() { numeric_data<qint64>(); }
+    void qint64CompareEq() { compare_eq<qint64>(); }
 };
 
 template <typename T>
@@ -75,5 +105,30 @@ void tst_toString::numeric()
     }
 }
 
+template <typename T>
+void tst_toString::compare()
+{
+    QFETCH(T, datum);
+
+    QBENCHMARK {
+        QCOMPARE(datum, datum);
+    }
+}
+
+template <typename T>
+void tst_toString::compare_eq()
+{
+    QFETCH(T, datum);
+
+    if constexpr (std::numeric_limits<T>::has_quiet_NaN) {
+        if (qIsNaN(datum))
+            QSKIP("Unlike QCOMPARE, QCOMPARE_EQ doesn't handle NaN specially");
+    }
+
+    QBENCHMARK {
+        QCOMPARE_EQ(datum, datum);
+    }
+}
+
 QTEST_MAIN(tst_toString)
 #include "tst_tostring.moc"