CSSValue Immediates: Change CSSValue to an object instead of a pointer

Source/core/css/StylePropertySet.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Research In Motion Limited. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 24 matching lines @@
 
 #ifndef NDEBUG
 #include "wtf/text/CString.h"
 #include <stdio.h>
 #endif
 
 namespace blink {
 
 static size_t sizeForImmutableStylePropertySetWithPropertyCount(unsigned count)
 {
-    return sizeof(ImmutableStylePropertySet) - sizeof(void*) + sizeof(CSSValue*) * count + sizeof(StylePropertyMetadata) * count;
+    return sizeof(ImmutableStylePropertySet) - sizeof(void*) + sizeof(CSSValue) * count + sizeof(StylePropertyMetadata) * count;
 }
 
 PassRefPtrWillBeRawPtr<ImmutableStylePropertySet> ImmutableStylePropertySet::create(const CSSProperty* properties, unsigned count, CSSParserMode cssParserMode)
 {
     ASSERT(count <= MaxArraySize);
 #if ENABLE(OILPAN)
     void* slot = Heap::allocate<StylePropertySet>(sizeForImmutableStylePropertySetWithPropertyCount(count));
 #else
     void* slot = WTF::fastMalloc(sizeForImmutableStylePropertySetWithPropertyCount(count));
 #endif // ENABLE(OILPAN)
@@ skipping 18 matching lines @@
 {
     m_propertyVector.reserveInitialCapacity(length);
     for (unsigned i = 0; i < length; ++i)
         m_propertyVector.uncheckedAppend(properties[i]);
 }
 
 ImmutableStylePropertySet::ImmutableStylePropertySet(const CSSProperty* properties, unsigned length, CSSParserMode cssParserMode)
     : StylePropertySet(cssParserMode, length)
 {
     StylePropertyMetadata* metadataArray = const_cast<StylePropertyMetadata*>(this->metadataArray());
-    RawPtrWillBeMember<CSSValue>* valueArray = const_cast<RawPtrWillBeMember<CSSValue>*>(this->valueArray());
+    CSSValue* valueArray = const_cast<CSSValue*>(this->valueArray());
     for (unsigned i = 0; i < m_arraySize; ++i) {
         metadataArray[i] = properties[i].metadata();
-        valueArray[i] = properties[i].value();
-#if !ENABLE(OILPAN)
-        valueArray[i]->ref();
-#endif
+        // Can't use operator= here since the valueArray[i] is an invalid CSSValue.
+        new(&valueArray[i]) CSSValue(properties[i].value());
     }
 }
 
 ImmutableStylePropertySet::~ImmutableStylePropertySet()
 {
 #if !ENABLE(OILPAN)
-    RawPtrWillBeMember<CSSValue>* valueArray = const_cast<RawPtrWillBeMember<CSSValue>*>(this->valueArray());
+    CSSValue* valueArray = const_cast<CSSValue*>(this->valueArray());
     for (unsigned i = 0; i < m_arraySize; ++i) {
-        // Checking for nullptr here is a workaround to prevent crashing.  http://crbug.com/449032
-        if (valueArray[i])
-            valueArray[i]->deref();
+        valueArray[i].~CSSValue();
     }
 #endif
 }
 
 int ImmutableStylePropertySet::findPropertyIndex(CSSPropertyID propertyID) const
 {
     // Convert here propertyID into an uint16_t to compare it with the metadata's m_propertyID to avoid
     // the compiler converting it to an int multiple times in the loop.
     uint16_t id = static_cast<uint16_t>(propertyID);
     for (int n = m_arraySize - 1 ; n >= 0; --n) {
         if (metadataArray()[n].m_propertyID == id) {
             // Only enabled properties should be part of the style.
             ASSERT(CSSPropertyMetadata::isEnabledProperty(propertyID));
             return n;
         }
     }
 
     return -1;
 }
 
 DEFINE_TRACE_AFTER_DISPATCH(ImmutableStylePropertySet)
 {
-    const RawPtrWillBeMember<CSSValue>* values = valueArray();
+    const CSSValue* values = valueArray();
     for (unsigned i = 0; i < m_arraySize; i++)
         visitor->trace(values[i]);
     StylePropertySet::traceAfterDispatch(visitor);
 }
 
 MutableStylePropertySet::MutableStylePropertySet(const StylePropertySet& other)
     : StylePropertySet(other.cssParserMode())
 {
     if (other.isMutable()) {
         m_propertyVector = toMutableStylePropertySet(other).m_propertyVector;
     } else {
         m_propertyVector.reserveInitialCapacity(other.propertyCount());
         for (unsigned i = 0; i < other.propertyCount(); ++i)
             m_propertyVector.uncheckedAppend(other.propertyAt(i).toCSSProperty());
     }
 }
 
 String StylePropertySet::getPropertyValue(CSSPropertyID propertyID) const
 {
-    RefPtrWillBeRawPtr<CSSValue> value = getPropertyCSSValue(propertyID);
+    NullableCSSValue value = getPropertyCSSValue(propertyID);
     if (value)
         return value->cssText();
 
     return StylePropertySerializer(*this).getPropertyValue(propertyID);
 }
 
-PassRefPtrWillBeRawPtr<CSSValue> StylePropertySet::getPropertyCSSValue(CSSPropertyID propertyID) const
+NullableCSSValue StylePropertySet::getPropertyCSSValue(CSSPropertyID propertyID) const
 {
     int foundPropertyIndex = findPropertyIndex(propertyID);
     if (foundPropertyIndex == -1)
         return nullptr;
     return propertyAt(foundPropertyIndex).value();
 }
 
 DEFINE_TRACE(StylePropertySet)
 {
     if (m_isMutable)
@@ skipping 31 matching lines @@
     }
 
     int foundPropertyIndex = findPropertyIndex(propertyID);
     if (foundPropertyIndex == -1) {
         if (returnText)
             *returnText = "";
         return false;
     }
 
     if (returnText)
-        *returnText = propertyAt(foundPropertyIndex).value()->cssText();
+        *returnText = propertyAt(foundPropertyIndex).value().cssText();
 
     // A more efficient removal strategy would involve marking entries as empty
     // and sweeping them when the vector grows too big.
     m_propertyVector.remove(foundPropertyIndex);
 
     return true;
 }
 
 bool StylePropertySet::propertyIsImportant(CSSPropertyID propertyID) const
 {
@@ skipping 33 matching lines @@
     // Setting the value to an empty string just removes the property in both IE and Gecko.
     // Setting it to null seems to produce less consistent results, but we treat it just the same.
     if (value.isEmpty())
         return removeProperty(resolveCSSPropertyID(unresolvedProperty));
 
     // When replacing an existing property value, this moves the property to the end of the list.
     // Firefox preserves the position, and MSIE moves the property to the beginning.
     return CSSParser::parseValue(this, unresolvedProperty, value, important, cssParserMode(), contextStyleSheet);
 }
 
-void MutableStylePropertySet::setProperty(CSSPropertyID propertyID, PassRefPtrWillBeRawPtr<CSSValue> prpValue, bool important)
+void MutableStylePropertySet::setProperty(CSSPropertyID propertyID, CSSValue prpValue, bool important)
 {
     StylePropertyShorthand shorthand = shorthandForProperty(propertyID);
     if (!shorthand.length()) {
         setProperty(CSSProperty(propertyID, prpValue, important));
         return;
     }
 
     removePropertiesInSet(shorthand.properties(), shorthand.length());
 
-    RefPtrWillBeRawPtr<CSSValue> value = prpValue;
+    CSSValue value = prpValue;
     for (unsigned i = 0; i < shorthand.length(); ++i)
         m_propertyVector.append(CSSProperty(shorthand.properties()[i], value, important));
 }
 
 bool MutableStylePropertySet::setProperty(const CSSProperty& property, CSSProperty* slot)
 {
     if (!removeShorthandProperty(property.id())) {
         CSSProperty* toReplace = slot ? slot : findCSSPropertyWithID(property.id());
         if (toReplace && *toReplace == property)
             return false;
@@ skipping 57 matching lines @@
             setProperty(toMerge.toCSSProperty(), old);
         else
             m_propertyVector.append(toMerge.toCSSProperty());
     }
 }
 
 bool StylePropertySet::hasFailedOrCanceledSubresources() const
 {
     unsigned size = propertyCount();
     for (unsigned i = 0; i < size; ++i) {
-        if (propertyAt(i).value()->hasFailedOrCanceledSubresources())
+        if (propertyAt(i).value().hasFailedOrCanceledSubresources())
             return true;
     }
     return false;
 }
 
 // This is the list of properties we want to copy in the copyBlockProperties() function.
 // It is the list of CSS properties that apply specially to block-level elements.
 static const CSSPropertyID staticBlockProperties[] = {
     CSSPropertyOrphans,
     CSSPropertyOverflow, // This can be also be applied to replaced elements
@@ skipping 71 matching lines @@
 }
 
 CSSProperty* MutableStylePropertySet::findCSSPropertyWithID(CSSPropertyID propertyID)
 {
     int foundPropertyIndex = findPropertyIndex(propertyID);
     if (foundPropertyIndex == -1)
         return 0;
     return &m_propertyVector.at(foundPropertyIndex);
 }
 
-bool StylePropertySet::propertyMatches(CSSPropertyID propertyID, const CSSValue* propertyValue) const
+bool StylePropertySet::propertyMatches(CSSPropertyID propertyID, const CSSValue propertyValue) const
 {
     int foundPropertyIndex = findPropertyIndex(propertyID);
     if (foundPropertyIndex == -1)
         return false;
-    return propertyAt(foundPropertyIndex).value()->equals(*propertyValue);
+    return propertyAt(foundPropertyIndex).value().equals(propertyValue);
 }
 
 void MutableStylePropertySet::removeEquivalentProperties(const StylePropertySet* style)
 {
     Vector<CSSPropertyID> propertiesToRemove;
     unsigned size = m_propertyVector.size();
     for (unsigned i = 0; i < size; ++i) {
         PropertyReference property = propertyAt(i);
         if (style->propertyMatches(property.id(), property.value()))
             propertiesToRemove.append(property.id());
@@ skipping 20 matching lines @@
 PassRefPtrWillBeRawPtr<MutableStylePropertySet> StylePropertySet::mutableCopy() const
 {
     return adoptRefWillBeNoop(new MutableStylePropertySet(*this));
 }
 
 PassRefPtrWillBeRawPtr<MutableStylePropertySet> StylePropertySet::copyPropertiesInSet(const Vector<CSSPropertyID>& properties) const
 {
     WillBeHeapVector<CSSProperty, 256> list;
     list.reserveInitialCapacity(properties.size());
     for (unsigned i = 0; i < properties.size(); ++i) {
-        RefPtrWillBeRawPtr<CSSValue> value = getPropertyCSSValue(properties[i]);
+        NullableCSSValue value = getPropertyCSSValue(properties[i]);
         if (value)
-            list.append(CSSProperty(properties[i], value.release(), false));
+            list.append(CSSProperty(properties[i], *value, false));
     }
     return MutableStylePropertySet::create(list.data(), list.size());
 }
 
 CSSStyleDeclaration* MutableStylePropertySet::ensureCSSStyleDeclaration()
 {
     // FIXME: get rid of this weirdness of a CSSStyleDeclaration inside of a
     // style property set.
     if (m_cssomWrapper) {
         ASSERT(!static_cast<CSSStyleDeclaration*>(m_cssomWrapper.get())->parentRule());
@@ skipping 53 matching lines @@
 {
     return adoptRefWillBeNoop(new MutableStylePropertySet(cssParserMode));
 }
 
 PassRefPtrWillBeRawPtr<MutableStylePropertySet> MutableStylePropertySet::create(const CSSProperty* properties, unsigned count)
 {
     return adoptRefWillBeNoop(new MutableStylePropertySet(properties, count));
 }
 
 } // namespace blink