void RuleFeatureSet::updateInvalidationSets(const RuleData& ruleData)
{
InvalidationSetFeatures features;
auto result = extractInvalidationSetFeatures(ruleData.selector(), features, false);
if (result.first) {
features.forceSubtree = result.second == ForceSubtree;
addFeaturesToInvalidationSets(*result.first, features);
}
// If any ::before and ::after rules specify 'content: attr(...)', we
// need to create invalidation sets for those attributes.
if (features.hasBeforeOrAfter)
updateInvalidationSetsForContentAttribute(ruleData);
}
std::pair<const CSSSelector*, RuleFeatureSet::UseFeaturesType>
RuleFeatureSet::extractInvalidationSetFeatures(const CSSSelector& selector, InvalidationSetFeatures& features, PositionType position, CSSSelector::PseudoType pseudo)
{
bool foundFeatures = false;
for (const CSSSelector* current = &selector; current; current = current->tagHistory()) {
if (pseudo != CSSSelector::PseudoNot)
foundFeatures |= extractInvalidationSetFeature(*current, features);
// Initialize the entry in the invalidation set map, if supported.
if (InvalidationSet* invalidationSet = invalidationSetForSelector(*current, InvalidateDescendants)) {
if (position == Subject)
invalidationSet->setInvalidatesSelf();
} else {
if (requiresSubtreeInvalidation(*current)) {
// Fall back to use subtree invalidations, even for features in the
// rightmost compound selector. Returning the start &selector here
// will make addFeaturesToInvalidationSets start marking invalidation
// sets for subtree recalc for features in the rightmost compound
// selector.
return std::make_pair(&selector, ForceSubtree);
}
if (const CSSSelectorList* selectorList = current->selectorList()) {
ASSERT(supportsInvalidationWithSelectorList(current->pseudoType()));
const CSSSelector* subSelector = selectorList->first();
bool allSubSelectorsHaveFeatures = !!subSelector;
for (; subSelector; subSelector = CSSSelectorList::next(*subSelector)) {
auto result = extractInvalidationSetFeatures(*subSelector, features, position, current->pseudoType());
if (result.first) {
// A non-null selector return means the sub-selector contained a
// selector which requiresSubtreeInvalidation(). Return the rightmost
// selector to mark for subtree recalcs like above.
return std::make_pair(&selector, ForceSubtree);
}
allSubSelectorsHaveFeatures &= result.second == UseFeatures;
}
foundFeatures |= allSubSelectorsHaveFeatures;
}
}
if (current->relation() == CSSSelector::SubSelector)
continue;
features.treeBoundaryCrossing = current->isShadowSelector();
features.adjacent = current->isAdjacentSelector();
if (current->relation() == CSSSelector::DirectAdjacent)
features.maxDirectAdjacentSelectors = 1;
return std::make_pair(current->tagHistory(), foundFeatures ? UseFeatures : ForceSubtree);
}
return std::make_pair(nullptr, foundFeatures ? UseFeatures : ForceSubtree);
}
RuleFeatureSet::InvalidationSetMode RuleFeatureSet::updateInvalidationSets(const CSSSelector& selector)
{
InvalidationSetMode mode = invalidationSetModeForSelector(selector);
if (mode != AddFeatures)
return mode;
InvalidationSetFeatures features;
const CSSSelector* current = extractInvalidationSetFeatures(selector, features);
if (current) {
bool wholeSubtree = current->relation() == CSSSelector::DirectAdjacent || current->relation() == CSSSelector::IndirectAdjacent;
current = current->tagHistory();
if (current)
addFeaturesToInvalidationSets(*current, features, wholeSubtree);
}
return AddFeatures;
}
const CSSSelector* RuleFeatureSet::extractInvalidationSetFeatures(const CSSSelector& selector, InvalidationSetFeatures& features)
{
const CSSSelector* lastSelector = &selector;
for (; lastSelector; lastSelector = lastSelector->tagHistory()) {
extractInvalidationSetFeature(*lastSelector, features);
// Initialize the entry in the invalidation set map, if supported.
invalidationSetForSelector(*lastSelector);
if (lastSelector->pseudoType() == CSSSelector::PseudoHost || lastSelector->pseudoType() == CSSSelector::PseudoAny) {
if (const CSSSelectorList* selectorList = lastSelector->selectorList()) {
for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(*selector))
extractInvalidationSetFeatures(*selector, features);
}
}
if (lastSelector->relation() != CSSSelector::SubSelector)
break;
}
return lastSelector;
}
// selector is the selector immediately to the left of the rightmost combinator.
// siblingFeatures is null if selector is not immediately to the left of a sibling combinator.
// descendantFeatures has the features of the rightmost compound selector.
void RuleFeatureSet::addFeaturesToInvalidationSets(const CSSSelector* selector, InvalidationSetFeatures* siblingFeatures, InvalidationSetFeatures& descendantFeatures)
{
const CSSSelector* lastCompoundSelectorInAdjacentChain = selector;
// We set siblingFeatures to &localFeatures if we find a rightmost sibling combinator.
InvalidationSetFeatures localFeatures;
for (const CSSSelector* current = selector; current; current = current->tagHistory()) {
InvalidationType type = siblingFeatures ? InvalidateSiblings : InvalidateDescendants;
if (InvalidationSet* invalidationSet = invalidationSetForSelector(*current, type)) {
if (siblingFeatures) {
SiblingInvalidationSet* siblingInvalidationSet = toSiblingInvalidationSet(invalidationSet);
siblingInvalidationSet->updateMaxDirectAdjacentSelectors(siblingFeatures->maxDirectAdjacentSelectors);
addFeaturesToInvalidationSet(*invalidationSet, *siblingFeatures);
if (siblingFeatures == &descendantFeatures)
siblingInvalidationSet->descendants().setInvalidatesSelf();
else
addFeaturesToInvalidationSet(siblingInvalidationSet->descendants(), descendantFeatures);
} else {
addFeaturesToInvalidationSet(*invalidationSet, descendantFeatures);
}
} else {
if (current->isHostPseudoClass())
descendantFeatures.treeBoundaryCrossing = true;
if (current->isInsertionPointCrossing())
descendantFeatures.insertionPointCrossing = true;
if (const CSSSelectorList* selectorList = current->selectorList()) {
ASSERT(supportsInvalidationWithSelectorList(current->pseudoType()));
for (const CSSSelector* subSelector = selectorList->first(); subSelector; subSelector = CSSSelectorList::next(*subSelector))
addFeaturesToInvalidationSets(subSelector, siblingFeatures, descendantFeatures);
}
}
if (current->relation() == CSSSelector::SubSelector)
continue;
if (current->isShadowSelector())
descendantFeatures.treeBoundaryCrossing = true;
if (!current->isAdjacentSelector()) {
lastCompoundSelectorInAdjacentChain = current->tagHistory();
siblingFeatures = nullptr;
continue;
}
if (siblingFeatures) {
if (siblingFeatures->maxDirectAdjacentSelectors == UINT_MAX)
continue;
if (current->relation() == CSSSelector::DirectAdjacent)
siblingFeatures->maxDirectAdjacentSelectors++;
else
siblingFeatures->maxDirectAdjacentSelectors = UINT_MAX;
continue;
}
localFeatures = InvalidationSetFeatures();
auto result = extractInvalidationSetFeatures(*lastCompoundSelectorInAdjacentChain, localFeatures, Ancestor);
ASSERT(result.first);
localFeatures.forceSubtree = result.second == ForceSubtree;
siblingFeatures = &localFeatures;
}
}
