1 files changed, 160 insertions, 0 deletions
diff --git a/src/qml/compiler/qv4util_p.h b/src/qml/compiler/qv4util_p.h
new file mode 100644
index 0000000000..4215003e7c
--- /dev/null
+++ b/src/qml/compiler/qv4util_p.h
@@ -0,0 +1,160 @@
+// Copyright (C) 2019 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+#ifndef QV4UTIL_H
+#define QV4UTIL_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/QBitArray>
+#include <QtCore/private/qglobal_p.h>
+#include <algorithm>
+#include <vector>
+
+QT_BEGIN_NAMESPACE
+
+namespace QV4 {
+
+#if !defined(BROKEN_STD_VECTOR_BOOL_OR_BROKEN_STD_FIND)
+// Sanity:
+class BitVector
+{
+    std::vector<bool> bits;
+
+public:
+    BitVector(int size = 0, bool value = false)
+        : bits(size, value)
+    {}
+
+    void clear()
+    { bits = std::vector<bool>(bits.size(), false); }
+
+    void reserve(int size)
+    { bits.reserve(size); }
+
+    int size() const
+    {
+        Q_ASSERT(bits.size() < INT_MAX);
+        return static_cast<int>(bits.size());
+    }
+
+    void resize(int newSize)
+    { bits.resize(newSize); }
+
+    void resize(int newSize, bool newValue)
+    { bits.resize(newSize, newValue); }
+
+    void assign(int newSize, bool value)
+    { bits.assign(newSize, value); }
+
+    int findNext(int start, bool value, bool wrapAround) const
+    {
+        // The ++operator of std::vector<bool>::iterator in libc++ has a bug when using it on an
+        // iterator pointing to the last element. It will not be set to ::end(), but beyond
+        // that. (It will be set to the first multiple of the native word size that is bigger
+        // than size().)
+        //
+        // See http://llvm.org/bugs/show_bug.cgi?id=19663
+        //
+        // The work-around is to calculate the distance, and compare it to the size() to see if it's
+        // beyond the end, or take the minimum of the distance and the size.
+
+        size_t pos = std::distance(bits.begin(),
+                                   std::find(bits.begin() + start, bits.end(), value));
+        if (wrapAround && pos >= static_cast<size_t>(size()))
+            pos = std::distance(bits.begin(),
+                                std::find(bits.begin(), bits.begin() + start, value));
+
+        pos = qMin(pos, static_cast<size_t>(size()));
+
+        Q_ASSERT(pos <= static_cast<size_t>(size()));
+        Q_ASSERT(pos < INT_MAX);
+
+        return static_cast<int>(pos);
+    }
+
+    bool at(int idx) const
+    { return bits.at(idx); }
+
+    void setBit(int idx)
+    { bits[idx] = true; }
+
+    void clearBit(int idx)
+    { bits[idx] = false; }
+};
+#else // Insanity:
+class BitVector
+{
+    QBitArray bits;
+
+public:
+    BitVector(int size = 0, bool value = false)
+        : bits(size, value)
+    {}
+
+    void clear()
+    { bits = QBitArray(bits.size(), false); }
+
+    void reserve(int size)
+    { Q_UNUSED(size); }
+
+    int size() const
+    { return bits.size(); }
+
+    void resize(int newSize)
+    { bits.resize(newSize); }
+
+    void resize(int newSize, bool newValue)
+    {
+        int oldSize = bits.size();
+        bits.resize(newSize);
+        bits.fill(newValue, oldSize, bits.size());
+    }
+
+    void assign(int newSize, bool value)
+    {
+        bits.resize(newSize);
+        bits.fill(value);
+    }
+
+    int findNext(int start, bool value, bool wrapAround) const
+    {
+        for (int i = start, ei = size(); i < ei; ++i) {
+            if (at(i) == value)
+                return i;
+        }
+
+        if (wrapAround) {
+            for (int i = 0, ei = start; i < ei; ++i) {
+                if (at(i) == value)
+                    return i;
+            }
+        }
+
+        return size();
+    }
+
+    bool at(int idx) const
+    { return bits.at(idx); }
+
+    void setBit(int idx)
+    { bits[idx] = true; }
+
+    void clearBit(int idx)
+    { bits[idx] = false; }
+};
+#endif
+
+}
+
+QT_END_NAMESPACE
+
+#endif // QV4UTIL_H