Source/JavaScriptCore/runtime/ObjectAdaptiveStructureWatchpoint.h

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 #pragma once

 #include "ObjectPropertyCondition.h"
 #include "PackedCellPtr.h"
 #include "Watchpoint.h"

 namespace JSC {

 class ObjectAdaptiveStructureWatchpoint final : public Watchpoint {
 public:
     ObjectAdaptiveStructureWatchpoint(JSCell* owner, const ObjectPropertyCondition& key, InlineWatchpointSet& watchpointSet)
         : Watchpoint(Watchpoint::Type::ObjectAdaptiveStructure)
         , m_key(key)
         , m_owner(owner)
         , m_watchpointSet(watchpointSet)
     {
         RELEASE_ASSERT(key.kind() != PropertyCondition::Equivalence);
         RELEASE_ASSERT(key.watchingRequiresStructureTransitionWatchpoint());
         RELEASE_ASSERT(!key.watchingRequiresReplacementWatchpoint());
         RELEASE_ASSERT(watchpointSet.state() == IsWatched);
     }

     const ObjectPropertyCondition& key() const { return m_key; }

     void install(VM&);

     void fireInternal(VM&, const FireDetail&);

 private:
     // Own destructor may not be called. Keep members trivially destructible.
     JSC_WATCHPOINT_FIELD(ObjectPropertyCondition, m_key);
     JSC_WATCHPOINT_FIELD(JSCell*, m_owner);
     JSC_WATCHPOINT_FIELD(InlineWatchpointSet&, m_watchpointSet);
 };

 inline void ObjectAdaptiveStructureWatchpoint::install(VM&)
 {
     RELEASE_ASSERT(m_key.isWatchable(PropertyCondition::MakeNoChanges));

     m_key.object()->structure()->addTransitionWatchpoint(this);
 }

 inline void ObjectAdaptiveStructureWatchpoint::fireInternal(VM& vm, const FireDetail&)
 {
     if (!m_owner->isLive())
         return;

     if (m_key.isWatchable(PropertyCondition::EnsureWatchability)) {
         install(vm);
         return;
     }

     m_watchpointSet.fireAll(vm, StringFireDetail("Object Property is added."));
 }

 } // namespace JSC