Fix the benchmark for QList::removeAll()

The benchmark was making assumptions about number of
constructor/assignment operator calls, which are not valid in Qt 6,
after the implementation of QList has changed. Considering that we
already check number of constructions, copy constructions, etc., in
tst_qlist.cpp, remove the checks from the benchmark.

As a driveby, fix the following warning:
"warning: parameter 'i' shadows member inherited from type 'MyBase'"

Pick-to: 6.2
Fixes: QTBUG-95096
Change-Id: Ida68fa5803641c8fa84f8309c0093986ed4c0a2b
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>

1 files changed, 25 insertions, 92 deletions

diff --git a/tests/benchmarks/corelib/tools/qlist/tst_bench_qlist.cpp b/tests/benchmarks/corelib/tools/qlist/tst_bench_qlist.cpp
index 9d6126ca7b..90c1e02a81 100644
--- a/tests/benchmarks/corelib/tools/qlist/tst_bench_qlist.cpp
+++ b/tests/benchmarks/corelib/tools/qlist/tst_bench_qlist.cpp
@@ -35,88 +35,42 @@ static const int N = 1000;
 
 struct MyBase
 {
-    MyBase(int i_)
-        : isCopy(false)
-    {
-        ++liveCount;
-
-        i = i_;
-    }
+    MyBase(int i_) : i(i_) { }
 
-    MyBase(const MyBase &other)
-        : isCopy(true)
-    {
-        if (isCopy)
-            ++copyCount;
-        ++liveCount;
-
-        i = other.i;
-    }
+    MyBase(const MyBase &other) : i(other.i) { }
 
     MyBase &operator=(const MyBase &other)
     {
-        if (!isCopy) {
-            isCopy = true;
-            ++copyCount;
-        } else {
-            ++errorCount;
-        }
-
         i = other.i;
         return *this;
     }
 
-    ~MyBase()
-    {
-        if (isCopy) {
-            if (!copyCount)
-                ++errorCount;
-            else
-                --copyCount;
-        }
-        if (!liveCount)
-            ++errorCount;
-        else
-            --liveCount;
-    }
-
     bool operator==(const MyBase &other) const
     { return i == other.i; }
 
 protected:
-    ushort i;
-    bool isCopy;
-
-public:
-    static int errorCount;
-    static int liveCount;
-    static int copyCount;
+    int i;
 };
 
-int MyBase::errorCount = 0;
-int MyBase::liveCount = 0;
-int MyBase::copyCount = 0;
-
 struct MyPrimitive : public MyBase
 {
-    MyPrimitive(int i = -1) : MyBase(i)
-    { ++errorCount; }
-    MyPrimitive(const MyPrimitive &other) : MyBase(other)
-    { ++errorCount; }
+    MyPrimitive(int i_ = -1) : MyBase(i_) { }
+    MyPrimitive(const MyPrimitive &other) : MyBase(other) { }
     MyPrimitive &operator=(const MyPrimitive &other)
-    { ++errorCount; MyBase::operator=(other); return *this; }
-    ~MyPrimitive()
-    { ++errorCount; }
+    {
+        MyBase::operator=(other);
+        return *this;
+    }
 };
 
 struct MyMovable : public MyBase
 {
-    MyMovable(int i = -1) : MyBase(i) {}
+    MyMovable(int i_ = -1) : MyBase(i_) {}
 };
 
 struct MyComplex : public MyBase
 {
-    MyComplex(int i = -1) : MyBase(i) {}
+    MyComplex(int i_ = -1) : MyBase(i_) {}
 };
 
 QT_BEGIN_NAMESPACE
@@ -283,50 +237,29 @@ private:
 template <class T>
 void tst_QList::removeAll_impl() const
 {
-    QSKIP("QTBUG-95096: known to be broken (for some test-cases) since Qt 6.0");
     QFETCH(QList<int>, i10);
     QFETCH(int, itemsToRemove);
 
     constexpr int valueToRemove = 5;
-    constexpr bool isComplex = QTypeInfo<T>::isComplex;
 
-    MyBase::errorCount = 0;
-    MyBase::liveCount = 0;
-    MyBase::copyCount = 0;
-    {
-        QList<T> list;
-        QCOMPARE(MyBase::liveCount, 0);
-        QCOMPARE(MyBase::copyCount, 0);
-
-        for (int i = 0; i < 10 * N; ++i) {
-            T t(i10.at(i % 10));
-            list.append(t);
-        }
-        QCOMPARE(MyBase::liveCount, isComplex ? list.size() : 0);
-        QCOMPARE(MyBase::copyCount, isComplex ? list.size() : 0);
+    QList<T> list;
+    for (int i = 0; i < 10 * N; ++i) {
+        T t(i10.at(i % 10));
+        list.append(t);
+    }
 
-        T t(valueToRemove);
-        QCOMPARE(MyBase::liveCount, isComplex ? list.size() + 1 : 1);
-        QCOMPARE(MyBase::copyCount, isComplex ? list.size() : 0);
+    T t(valueToRemove);
 
-        int removedCount = 0; // make compiler happy by setting to 0
-        QList<T> l;
+    qsizetype removedCount = 0; // make compiler happy by setting to 0
+    QList<T> l;
 
-        QBENCHMARK {
-            l = list;
-            removedCount = l.removeAll(t);
-        }
-        QCOMPARE(removedCount, itemsToRemove * N);
-        QCOMPARE(l.size() + removedCount, list.size());
-        QVERIFY(!l.contains(valueToRemove));
-
-        QCOMPARE(MyBase::liveCount,
-                 isComplex ? l.isDetached() ? list.size() + l.size() + 1 : list.size() + 1 : 1);
-        QCOMPARE(MyBase::copyCount,
-                 isComplex ? l.isDetached() ? list.size() + l.size() : list.size() : 0);
+    QBENCHMARK {
+        l = list;
+        removedCount = l.removeAll(t);
     }
-    if (isComplex)
-        QCOMPARE(MyBase::errorCount, 0);
+    QCOMPARE(removedCount, itemsToRemove * N);
+    QCOMPARE(l.size() + removedCount, list.size());
+    QVERIFY(!l.contains(valueToRemove));
 }
 
 void tst_QList::removeAll_primitive_data()