Move string data into subclass

Change-Id: I95dcdda8c68e2a5c36244798c8c10dcfdd69d2c2
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

7 files changed, 115 insertions, 99 deletions

diff --git a/src/qml/jsruntime/qv4identifier.cpp b/src/qml/jsruntime/qv4identifier.cpp
index 87fbd6f8e4..b78020ed13 100644
--- a/src/qml/jsruntime/qv4identifier.cpp
+++ b/src/qml/jsruntime/qv4identifier.cpp
@@ -149,8 +149,8 @@ const IdentifierHashEntry *IdentifierHashBase::lookup(String *str) const
 {
     if (!d)
         return 0;
-    if (str->identifier)
-        return lookup(str->identifier);
+    if (str->stringData()->identifier)
+        return lookup(str->stringData()->identifier);
     return lookup(str->toQString());
 }
 
diff --git a/src/qml/jsruntime/qv4identifiertable.cpp b/src/qml/jsruntime/qv4identifiertable.cpp
index 3b56b5cf9f..2d127af0e6 100644
--- a/src/qml/jsruntime/qv4identifiertable.cpp
+++ b/src/qml/jsruntime/qv4identifiertable.cpp
@@ -69,7 +69,7 @@ IdentifierTable::~IdentifierTable()
 {
     for (int i = 0; i < alloc; ++i)
         if (entries[i])
-            delete entries[i]->identifier;
+            delete entries[i]->stringData()->identifier;
     free(entries);
 }
 
@@ -80,9 +80,9 @@ void IdentifierTable::addEntry(String *str)
     if (str->subtype() == String::StringType_ArrayIndex)
         return;
 
-    str->identifier = new Identifier;
-    str->identifier->string = str->toQString();
-    str->identifier->hashValue = hash;
+    str->stringData()->identifier = new Identifier;
+    str->stringData()->identifier->string = str->toQString();
+    str->stringData()->identifier->hashValue = hash;
 
     bool grow = (alloc <= size*2);
 
@@ -95,7 +95,7 @@ void IdentifierTable::addEntry(String *str)
             String *e = entries[i];
             if (!e)
                 continue;
-            uint idx = e->stringHash % newAlloc;
+            uint idx = e->stringData()->stringHash % newAlloc;
             while (newEntries[idx]) {
                 ++idx;
                 idx %= newAlloc;
@@ -123,7 +123,7 @@ String *IdentifierTable::insertString(const QString &s)
     uint hash = String::createHashValue(s.constData(), s.length());
     uint idx = hash % alloc;
     while (String *e = entries[idx]) {
-        if (e->stringHash == hash && e->toQString() == s)
+        if (e->stringData()->stringHash == hash && e->toQString() == s)
             return e;
         ++idx;
         idx %= alloc;
@@ -137,29 +137,29 @@ String *IdentifierTable::insertString(const QString &s)
 
 Identifier *IdentifierTable::identifierImpl(const String *str)
 {
-    if (str->identifier)
-        return str->identifier;
+    if (str->stringData()->identifier)
+        return str->stringData()->identifier;
     uint hash = str->hashValue();
     if (str->subtype() == String::StringType_ArrayIndex)
         return 0;
 
     uint idx = hash % alloc;
     while (String *e = entries[idx]) {
-        if (e->stringHash == hash && e->isEqualTo(str)) {
-            str->identifier = e->identifier;
-            return e->identifier;
+        if (e->stringData()->stringHash == hash && e->isEqualTo(str)) {
+            str->stringData()->identifier = e->stringData()->identifier;
+            return e->stringData()->identifier;
         }
         ++idx;
         idx %= alloc;
     }
 
     addEntry(const_cast<QV4::String *>(str));
-    return str->identifier;
+    return str->stringData()->identifier;
 }
 
 Identifier *IdentifierTable::identifier(const QString &s)
 {
-    return insertString(s)->identifier;
+    return insertString(s)->stringData()->identifier;
 }
 
 Identifier *IdentifierTable::identifier(const char *s, int len)
@@ -171,15 +171,15 @@ Identifier *IdentifierTable::identifier(const char *s, int len)
     QLatin1String latin(s, len);
     uint idx = hash % alloc;
     while (String *e = entries[idx]) {
-        if (e->stringHash == hash && e->toQString() == latin)
-            return e->identifier;
+        if (e->stringData()->stringHash == hash && e->toQString() == latin)
+            return e->stringData()->identifier;
         ++idx;
         idx %= alloc;
     }
 
     String *str = engine->newString(QString::fromLatin1(s, len))->getPointer();
     addEntry(str);
-    return str->identifier;
+    return str->stringData()->identifier;
 }
 
 }
diff --git a/src/qml/jsruntime/qv4identifiertable_p.h b/src/qml/jsruntime/qv4identifiertable_p.h
index 2f5ba0d707..249a45811d 100644
--- a/src/qml/jsruntime/qv4identifiertable_p.h
+++ b/src/qml/jsruntime/qv4identifiertable_p.h
@@ -69,8 +69,8 @@ public:
     String *insertString(const QString &s);
 
     Identifier *identifier(const String *str) {
-        if (str->identifier)
-            return str->identifier;
+        if (str->stringData()->identifier)
+            return str->stringData()->identifier;
         return identifierImpl(str);
     }
 
@@ -82,11 +82,11 @@ public:
     void mark(ExecutionEngine *e) {
         for (int i = 0; i < alloc; ++i) {
             String *entry = entries[i];
-            if (!entry || entry->data.markBit)
+            if (!entry || entry->markBit())
                 continue;
-            entry->data.markBit = 1;
-            Q_ASSERT(entry->data.internalClass->vtable->markObjects);
-            entry->data.internalClass->vtable->markObjects(entry, e);
+            entry->managedData()->markBit = 1;
+            Q_ASSERT(entry->internalClass()->vtable->markObjects);
+            entry->internalClass()->vtable->markObjects(entry, e);
         }
     }
 };
diff --git a/src/qml/jsruntime/qv4internalclass.cpp b/src/qml/jsruntime/qv4internalclass.cpp
index cb8841e681..e86a2d344b 100644
--- a/src/qml/jsruntime/qv4internalclass.cpp
+++ b/src/qml/jsruntime/qv4internalclass.cpp
@@ -181,7 +181,7 @@ InternalClass *InternalClass::changeMember(String *string, PropertyAttributes da
     if (data == propertyData.at(idx))
         return this;
 
-    Transition t = { { string->identifier }, (int)data.flags() };
+    Transition t = { { string->stringData()->identifier }, (int)data.flags() };
     QHash<Transition, InternalClass *>::const_iterator tit = transitions.constFind(t);
     if (tit != transitions.constEnd())
         return tit.value();
@@ -280,7 +280,7 @@ void InternalClass::addMember(Object *object, String *string, PropertyAttributes
 {
     data.resolve();
     object->internalClass()->engine->identifierTable->identifier(string);
-    if (object->internalClass()->propertyTable.lookup(string->identifier) < object->internalClass()->size) {
+    if (object->internalClass()->propertyTable.lookup(string->stringData()->identifier) < object->internalClass()->size) {
         changeMember(object, string, data, index);
         return;
     }
@@ -304,7 +304,7 @@ InternalClass *InternalClass::addMember(String *string, PropertyAttributes data,
     data.resolve();
     engine->identifierTable->identifier(string);
 
-    if (propertyTable.lookup(string->identifier) < size)
+    if (propertyTable.lookup(string->stringData()->identifier) < size)
         return changeMember(string, data, index);
 
     return addMemberImpl(string, data, index);
@@ -312,7 +312,7 @@ InternalClass *InternalClass::addMember(String *string, PropertyAttributes data,
 
 InternalClass *InternalClass::addMemberImpl(String *string, PropertyAttributes data, uint *index)
 {
-    Transition t = { { string->identifier }, (int)data.flags() };
+    Transition t = { { string->stringData()->identifier }, (int)data.flags() };
     QHash<Transition, InternalClass *>::const_iterator tit = transitions.constFind(t);
 
     if (index)
@@ -322,7 +322,7 @@ InternalClass *InternalClass::addMemberImpl(String *string, PropertyAttributes d
 
     // create a new class and add it to the tree
     InternalClass *newClass = engine->newClass(*this);
-    PropertyHash::Entry e = { string->identifier, newClass->size };
+    PropertyHash::Entry e = { string->stringData()->identifier, newClass->size };
     newClass->propertyTable.addEntry(e, newClass->size);
 
     // The incoming string can come from anywhere, so make sure to
@@ -382,7 +382,7 @@ uint InternalClass::find(const StringRef string)
 uint InternalClass::find(const String *string)
 {
     engine->identifierTable->identifier(string);
-    const Identifier *id = string->identifier;
+    const Identifier *id = string->stringData()->identifier;
 
     uint index = propertyTable.lookup(id);
     if (index < size)
diff --git a/src/qml/jsruntime/qv4object.cpp b/src/qml/jsruntime/qv4object.cpp
index cc123866be..9d5a491753 100644
--- a/src/qml/jsruntime/qv4object.cpp
+++ b/src/qml/jsruntime/qv4object.cpp
@@ -828,7 +828,7 @@ bool Object::internalDeleteProperty(const StringRef name)
     uint memberIdx = internalClass()->find(name);
     if (memberIdx != UINT_MAX) {
         if (internalClass()->propertyData[memberIdx].isConfigurable()) {
-            InternalClass::removeMember(this, name->identifier);
+            InternalClass::removeMember(this, name->identifier());
             return true;
         }
         if (engine()->currentContext()->strictMode)
diff --git a/src/qml/jsruntime/qv4string.cpp b/src/qml/jsruntime/qv4string.cpp
index e88888a71e..5c21548173 100644
--- a/src/qml/jsruntime/qv4string.cpp
+++ b/src/qml/jsruntime/qv4string.cpp
@@ -133,9 +133,9 @@ void String::destroy(Managed *that)
 void String::markObjects(Managed *that, ExecutionEngine *e)
 {
     String *s = static_cast<String *>(that);
-    if (s->largestSubLength) {
-        s->left->mark(e);
-        s->right->mark(e);
+    if (s->stringData()->largestSubLength) {
+        s->stringData()->left->mark(e);
+        s->stringData()->right->mark(e);
     }
 }
 
@@ -148,7 +148,7 @@ ReturnedValue String::get(Managed *m, const StringRef name, bool *hasProperty)
     if (name->equals(v4->id_length)) {
         if (hasProperty)
             *hasProperty = true;
-        return Primitive::fromInt32(that->_text->size).asReturnedValue();
+        return Primitive::fromInt32(that->stringData()->text->size).asReturnedValue();
     }
     PropertyAttributes attrs;
     Property *pd = v4->stringObjectClass->prototype->__getPropertyDescriptor__(name, &attrs);
@@ -168,7 +168,7 @@ ReturnedValue String::getIndexed(Managed *m, uint index, bool *hasProperty)
     Scope scope(engine);
     ScopedString that(scope, static_cast<String *>(m));
 
-    if (index < static_cast<uint>(that->_text->size)) {
+    if (index < static_cast<uint>(that->stringData()->text->size)) {
         if (hasProperty)
             *hasProperty = true;
         return Encode(engine->newString(that->toQString().mid(index, 1)));
@@ -217,7 +217,7 @@ PropertyAttributes String::query(const Managed *m, StringRef name)
 PropertyAttributes String::queryIndexed(const Managed *m, uint index)
 {
     const String *that = static_cast<const String *>(m);
-    return (index < static_cast<uint>(that->_text->size)) ? Attr_NotConfigurable|Attr_NotWritable : Attr_Invalid;
+    return (index < static_cast<uint>(that->stringData()->text->size)) ? Attr_NotConfigurable|Attr_NotWritable : Attr_Invalid;
 }
 
 bool String::deleteProperty(Managed *, const StringRef)
@@ -242,7 +242,7 @@ bool String::isEqualTo(Managed *t, Managed *o)
     String *other = static_cast<String *>(o);
     if (that->hashValue() != other->hashValue())
         return false;
-    if (that->identifier && that->identifier == other->identifier)
+    if (that->identifier() && that->identifier() == other->identifier())
         return true;
     if (that->subtype() >= StringType_UInt && that->subtype() == other->subtype())
         return true;
@@ -252,30 +252,37 @@ bool String::isEqualTo(Managed *t, Managed *o)
 
 
 String::String(ExecutionEngine *engine, const QString &text)
-    : Managed(engine->stringClass), _text(const_cast<QString &>(text).data_ptr())
-    , identifier(0), stringHash(UINT_MAX)
-    , largestSubLength(0)
+    : Managed(engine->stringClass)
 {
-    _text->ref.ref();
-    len = _text->size;
+    Data *d = stringData();
+    d->text = const_cast<QString &>(text).data_ptr();
+    d->text->ref.ref();
+    d->identifier = 0;
+    d->stringHash = UINT_MAX;
+    d->largestSubLength = 0;
+    d->len = stringData()->text->size;
     setSubtype(StringType_Unknown);
 }
 
 String::String(ExecutionEngine *engine, String *l, String *r)
     : Managed(engine->stringClass)
-    , left(l), right(r)
-    , stringHash(UINT_MAX), largestSubLength(qMax(l->largestSubLength, r->largestSubLength))
-    , len(l->len + r->len)
 {
     setSubtype(StringType_Unknown);
 
-    if (!l->largestSubLength && l->len > largestSubLength)
-        largestSubLength = l->len;
-    if (!r->largestSubLength && r->len > largestSubLength)
-        largestSubLength = r->len;
+    Data *d = stringData();
+    d->left = l;
+    d->right = r;
+    d->stringHash = UINT_MAX;
+    d->largestSubLength = qMax(l->stringData()->largestSubLength, r->stringData()->largestSubLength);
+    d->len = l->stringData()->len + r->stringData()->len;
+
+    if (!l->stringData()->largestSubLength && l->stringData()->len > stringData()->largestSubLength)
+        stringData()->largestSubLength = l->stringData()->len;
+    if (!r->stringData()->largestSubLength && r->stringData()->len > stringData()->largestSubLength)
+        stringData()->largestSubLength = r->stringData()->len;
 
     // make sure we don't get excessive depth in our strings
-    if (len > 256 && len >= 2*largestSubLength)
+    if (stringData()->len > 256 && stringData()->len >= 2*stringData()->largestSubLength)
         simplifyString();
 }
 
@@ -286,7 +293,7 @@ uint String::toUInt(bool *ok) const
     if (subtype() == StringType_Unknown)
         createHashValue();
     if (subtype() >= StringType_UInt)
-        return stringHash;
+        return stringData()->stringHash;
 
     // ### this conversion shouldn't be required
     double d = RuntimeHelpers::stringToNumber(toQString());
@@ -303,7 +310,7 @@ bool String::equals(const StringRef other) const
         return true;
     if (hashValue() != other->hashValue())
         return false;
-    if (identifier && identifier == other->identifier)
+    if (identifier() && identifier() == other->identifier())
         return true;
     if (subtype() >= StringType_UInt && subtype() == other->subtype())
         return true;
@@ -313,34 +320,34 @@ bool String::equals(const StringRef other) const
 
 void String::makeIdentifierImpl() const
 {
-    if (largestSubLength)
+    if (stringData()->largestSubLength)
         simplifyString();
-    Q_ASSERT(!largestSubLength);
+    Q_ASSERT(!stringData()->largestSubLength);
     engine()->identifierTable->identifier(this);
 }
 
 void String::simplifyString() const
 {
-    Q_ASSERT(largestSubLength);
+    Q_ASSERT(stringData()->largestSubLength);
 
     int l = length();
     QString result(l, Qt::Uninitialized);
     QChar *ch = const_cast<QChar *>(result.constData());
     recursiveAppend(ch);
-    _text = result.data_ptr();
-    _text->ref.ref();
-    identifier = 0;
-    largestSubLength = 0;
+    stringData()->text = result.data_ptr();
+    stringData()->text->ref.ref();
+    stringData()->identifier = 0;
+    stringData()->largestSubLength = 0;
 }
 
 QChar *String::recursiveAppend(QChar *ch) const
 {
-    if (largestSubLength) {
-        ch = left->recursiveAppend(ch);
-        ch = right->recursiveAppend(ch);
+    if (stringData()->largestSubLength) {
+        ch = stringData()->left->recursiveAppend(ch);
+        ch = stringData()->right->recursiveAppend(ch);
     } else {
-        memcpy(ch, _text->data(), _text->size*sizeof(QChar));
-        ch += _text->size;
+        memcpy(ch, stringData()->text->data(), stringData()->text->size*sizeof(QChar));
+        ch += stringData()->text->size;
     }
     return ch;
 }
@@ -348,17 +355,17 @@ QChar *String::recursiveAppend(QChar *ch) const
 
 void String::createHashValue() const
 {
-    if (largestSubLength)
+    if (stringData()->largestSubLength)
         simplifyString();
-    Q_ASSERT(!largestSubLength);
-    const QChar *ch = reinterpret_cast<const QChar *>(_text->data());
-    const QChar *end = ch + _text->size;
+    Q_ASSERT(!stringData()->largestSubLength);
+    const QChar *ch = reinterpret_cast<const QChar *>(stringData()->text->data());
+    const QChar *end = ch + stringData()->text->size;
 
     // array indices get their number as hash value
     bool ok;
-    stringHash = ::toArrayIndex(ch, end, &ok);
+    stringData()->stringHash = ::toArrayIndex(ch, end, &ok);
     if (ok) {
-        setSubtype((stringHash == UINT_MAX) ? StringType_UInt : StringType_ArrayIndex);
+        setSubtype((stringData()->stringHash == UINT_MAX) ? StringType_UInt : StringType_ArrayIndex);
         return;
     }
 
@@ -368,7 +375,7 @@ void String::createHashValue() const
         ++ch;
     }
 
-    stringHash = h;
+    stringData()->stringHash = h;
     setSubtype(StringType_Regular);
 }
 
diff --git a/src/qml/jsruntime/qv4string_p.h b/src/qml/jsruntime/qv4string_p.h
index 5f5d00cf77..615be29496 100644
--- a/src/qml/jsruntime/qv4string_p.h
+++ b/src/qml/jsruntime/qv4string_p.h
@@ -70,8 +70,8 @@ struct Q_QML_PRIVATE_EXPORT String : public Managed {
     String(ExecutionEngine *engine, const QString &text);
     String(ExecutionEngine *engine, String *l, String *n);
     ~String() {
-        if (!largestSubLength && !_text->ref.deref())
-            QStringData::deallocate(_text);
+        if (!stringData()->largestSubLength && !stringData()->text->ref.deref())
+            QStringData::deallocate(stringData()->text);
     }
 
     bool equals(const StringRef other) const;
@@ -80,8 +80,8 @@ struct Q_QML_PRIVATE_EXPORT String : public Managed {
             return true;
         if (hashValue() != other->hashValue())
             return false;
-        Q_ASSERT(!largestSubLength);
-        if (identifier && identifier == other->identifier)
+        Q_ASSERT(!stringData()->largestSubLength);
+        if (stringData()->identifier && stringData()->identifier == other->stringData()->identifier)
             return true;
         if (subtype() >= StringType_UInt && subtype() == other->subtype())
             return true;
@@ -94,10 +94,10 @@ struct Q_QML_PRIVATE_EXPORT String : public Managed {
     }
 
     inline QString toQString() const {
-        if (largestSubLength)
+        if (stringData()->largestSubLength)
             simplifyString();
-        QStringDataPtr ptr = { _text };
-        _text->ref.ref();
+        QStringDataPtr ptr = { stringData()->text };
+        stringData()->text->ref.ref();
         return QString(ptr);
     }
 
@@ -106,22 +106,22 @@ struct Q_QML_PRIVATE_EXPORT String : public Managed {
     inline unsigned hashValue() const {
         if (subtype() == StringType_Unknown)
             createHashValue();
-        Q_ASSERT(!largestSubLength);
+        Q_ASSERT(!stringData()->largestSubLength);
 
-        return stringHash;
+        return stringData()->stringHash;
     }
     uint asArrayIndex() const {
         if (subtype() == StringType_Unknown)
             createHashValue();
-        Q_ASSERT(!largestSubLength);
+        Q_ASSERT(!stringData()->largestSubLength);
         if (subtype() == StringType_ArrayIndex)
-            return stringHash;
+            return stringData()->stringHash;
         return UINT_MAX;
     }
     uint toUInt(bool *ok) const;
 
     void makeIdentifier() const {
-        if (identifier)
+        if (stringData()->identifier)
             return;
         makeIdentifierImpl();
     }
@@ -134,27 +134,36 @@ struct Q_QML_PRIVATE_EXPORT String : public Managed {
 
     bool startsWithUpper() const {
         const String *l = this;
-        while (l->largestSubLength)
-            l = l->left;
-        return l->_text->size && QChar::isUpper(l->_text->data()[0]);
+        while (l->stringData()->largestSubLength)
+            l = l->stringData()->left;
+        return l->stringData()->text->size && QChar::isUpper(l->stringData()->text->data()[0]);
     }
     int length() const {
-        Q_ASSERT((largestSubLength && (len == left->len + right->len)) || len == (uint)_text->size);
-        return len;
+        Q_ASSERT((stringData()->largestSubLength &&
+                  (stringData()->len == stringData()->left->stringData()->len + stringData()->right->stringData()->len)) ||
+                 stringData()->len == (uint)stringData()->text->size);
+        return stringData()->len;
     }
 
-    union {
-        mutable QStringData *_text;
-        mutable String *left;
+    struct Data {
+        union {
+            mutable QStringData *text;
+            mutable String *left;
+        };
+        union {
+            mutable Identifier *identifier;
+            mutable String *right;
+        };
+        mutable uint stringHash;
+        mutable uint largestSubLength;
+        uint len;
     };
-    union {
-        mutable Identifier *identifier;
-        mutable String *right;
-    };
-    mutable uint stringHash;
-    mutable uint largestSubLength;
-    uint len;
+    Data data;
+
+    const Data *stringData() const { return &data; }
+    Data *stringData() { return &data; }
 
+    Identifier *identifier() const { return stringData()->identifier; }
 
 protected:
     static void destroy(Managed *);