Remove QLocalePrivate::m_localeID

It was only used for toUpper/toLower but always computed in the
constructor, including QString::toLatin1 conversion and allocations.

This needlessly slows down all other uses, including supposedly "cheap"
operations QString::toDouble, or accesses inside QResourceFileEngine.

The benchmarks indicates that doing it always when needed is bearable.
There's still a lot of improvement potential on these code paths.

Change-Id: I88b637ee11f9f7ea614f8da4ec5df0bf40664fce
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>

src/corelib/tools/qlocale.cpp

@@ -284,51 +284,51 @@ QLocaleId QLocaleId::withLikelySubtagsRemoved() const
     return max;
 }
 
-QString QLocaleId::bcp47Name() const
+QByteArray QLocaleId::name(char separator) const
 {
     if (language_id == QLocale::AnyLanguage)
-        return QString();
+        return QByteArray();
     if (language_id == QLocale::C)
-        return QStringLiteral("C");
+        return QByteArrayLiteral("C");
 
-    const unsigned char *lang = language_code_list + 3*uint(language_id);
+    const unsigned char *lang = language_code_list + 3 * language_id;
     const unsigned char *script =
-            (script_id != QLocale::AnyScript ? script_code_list + 4*uint(script_id) : 0);
+            (script_id != QLocale::AnyScript ? script_code_list + 4 * script_id : 0);
     const unsigned char *country =
-            (country_id != QLocale::AnyCountry  ? country_code_list + 3*uint(country_id) : 0);
+            (country_id != QLocale::AnyCountry ? country_code_list + 3 * country_id : 0);
     char len = (lang[2] != 0 ? 3 : 2) + (script ? 4+1 : 0) + (country ? (country[2] != 0 ? 3 : 2)+1 : 0);
-    QString name(len, Qt::Uninitialized);
-    QChar *uc = name.data();
-    *uc++ = ushort(lang[0]);
-    *uc++ = ushort(lang[1]);
+    QByteArray name(len, Qt::Uninitialized);
+    char *uc = name.data();
+    *uc++ = lang[0];
+    *uc++ = lang[1];
     if (lang[2] != 0)
-        *uc++ = ushort(lang[2]);
+        *uc++ = lang[2];
     if (script) {
-        *uc++ = QLatin1Char('-');
-        *uc++ = ushort(script[0]);
-        *uc++ = ushort(script[1]);
-        *uc++ = ushort(script[2]);
-        *uc++ = ushort(script[3]);
+        *uc++ = separator;
+        *uc++ = script[0];
+        *uc++ = script[1];
+        *uc++ = script[2];
+        *uc++ = script[3];
     }
     if (country) {
-        *uc++ = QLatin1Char('-');
-        *uc++ = ushort(country[0]);
-        *uc++ = ushort(country[1]);
+        *uc++ = separator;
+        *uc++ = country[0];
+        *uc++ = country[1];
         if (country[2] != 0)
-            *uc++ = ushort(country[2]);
+            *uc++ = country[2];
     }
     return name;
 }
 
-QString QLocalePrivate::bcp47Name() const
+QByteArray QLocalePrivate::bcp47Name(char separator) const
 {
     if (m_data->m_language_id == QLocale::AnyLanguage)
-        return QString();
+        return QByteArray();
     if (m_data->m_language_id == QLocale::C)
-        return QStringLiteral("C");
+        return QByteArrayLiteral("C");
 
     QLocaleId localeId = QLocaleId::fromIds(m_data->m_language_id, m_data->m_script_id, m_data->m_country_id);
-    return localeId.withLikelySubtagsRemoved().bcp47Name();
+    return localeId.withLikelySubtagsRemoved().name(separator);
 }
 
 const QLocaleData *QLocaleData::findLocaleData(QLocale::Language language, QLocale::Script script, QLocale::Country country)
@@ -1080,7 +1080,7 @@ QString QLocale::name() const
 */
 QString QLocale::bcp47Name() const
 {
-    return d->bcp47Name();
+    return QString::fromLatin1(d->bcp47Name());
 }
 
 /*!
@@ -2494,7 +2494,7 @@ QString QLocale::toUpper(const QString &str) const
 {
 #ifdef QT_USE_ICU
     bool ok = true;
-    QString result = QIcu::toUpper(d->m_localeID, str, &ok);
+    QString result = QIcu::toUpper(d->bcp47Name('_'), str, &ok);
     if (ok)
         return result;
     // else fall through and use Qt's toUpper
@@ -2511,7 +2511,7 @@ QString QLocale::toLower(const QString &str) const
 {
 #ifdef QT_USE_ICU
     bool ok = true;
-    QString result = QIcu::toLower(d->m_localeID, str, &ok);
+    const QString result = QIcu::toLower(d->bcp47Name('_'), str, &ok);
     if (ok)
         return result;
     // else fall through and use Qt's toUpper
@@ -3662,14 +3662,14 @@ QStringList QLocale::uiLanguages() const
     const QLocaleId min = max.withLikelySubtagsRemoved();
 
     QStringList uiLanguages;
-    uiLanguages.append(min.bcp47Name());
+    uiLanguages.append(QString::fromLatin1(min.name()));
     if (id.script_id) {
         id.script_id = 0;
         if (id != min && id.withLikelySubtagsAdded() == max)
-            uiLanguages.append(id.bcp47Name());
+            uiLanguages.append(QString::fromLatin1(id.name()));
     }
     if (max != min && max != id)
-        uiLanguages.append(max.bcp47Name());
+        uiLanguages.append(QString::fromLatin1(max.name()));
     return uiLanguages;
 }
 

src/corelib/tools/qlocale_p.h

@@ -151,7 +151,7 @@ struct QLocaleId
     QLocaleId withLikelySubtagsAdded() const;
     QLocaleId withLikelySubtagsRemoved() const;
 
-    QString bcp47Name() const;
+    QByteArray name(char separator = '-') const;
 
     ushort language_id, script_id, country_id;
 };
@@ -212,8 +212,6 @@ public:
         : m_index(index), m_numberOptions(numberOptions)
     {
         m_data = dataPointerForIndex(index);
-        m_localeID = bcp47Name().toLatin1();
-        m_localeID.replace('-','_');
     }
 
     ~QLocalePrivate()
@@ -232,7 +230,7 @@ public:
     quint16 languageId() const { return m_data->m_language_id; }
     quint16 countryId() const { return m_data->m_country_id; }
 
-    QString bcp47Name() const;
+    QByteArray bcp47Name(char separator = '-') const;
 
     // ### QByteArray::fromRawData would be more optimal
     inline QString languageCode() const { return QLocalePrivate::languageToCode(QLocale::Language(m_data->m_language_id)); }
@@ -334,11 +332,9 @@ public:
     QString dateTimeToString(const QString &format, const QDate *date, const QTime *time,
                              const QLocale *q) const;
 
-    friend class QLocale;
     quint16 m_index;
     quint16 m_numberOptions;
     const QLocaleData *m_data;
-    QByteArray m_localeID;
 };
 
 inline char QLocalePrivate::digitToCLocale(QChar in) const

tests/benchmarks/corelib/tools/qlocale/main.cpp

@@ -0,0 +1,83 @@
+/****************************************************************************
+**
+** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QLocale>
+#include <QTest>
+
+class tst_QLocale : public QObject
+{
+    Q_OBJECT
+
+private Q_SLOTS:
+    void toUpper_QLocale_1();
+    void toUpper_QLocale_2();
+    void toUpper_QString();
+};
+
+static QString data()
+{
+    return QStringLiteral("/qt-5/qtbase/tests/benchmarks/corelib/tools/qlocale");
+}
+
+#define LOOP(s) for (int i = 0; i < 5000; ++i) { s; }
+
+void tst_QLocale::toUpper_QLocale_1()
+{
+    QString s = data();
+    QBENCHMARK { LOOP(QLocale().toUpper(s)) }
+}
+
+void tst_QLocale::toUpper_QLocale_2()
+{
+    QString s = data();
+    QLocale l;
+    QBENCHMARK { LOOP(l.toUpper(s)) }
+}
+
+void tst_QLocale::toUpper_QString()
+{
+    QString s = data();
+    QBENCHMARK { LOOP(s.toUpper()) }
+}
+
+QTEST_MAIN(tst_QLocale)
+
+#include "main.moc"

tests/benchmarks/corelib/tools/qlocale/qlocale.pro

@@ -0,0 +1,5 @@
+TARGET = tst_bench_qlocale
+QT = core testlib
+
+SOURCES += main.cpp
+DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0

tests/benchmarks/corelib/tools/tools.pro

@@ -5,6 +5,7 @@ SUBDIRS = \
         qbytearray \
         qcontiguouscache \
         qlist \
+        qlocale \
         qmap \
         qrect \
         qregexp \