/* * Copyright (C) 2012-2014 Apple Inc. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #ifndef VariableWatchpointSet_h #define VariableWatchpointSet_h #include "Watchpoint.h" #include "WriteBarrier.h" namespace JSC { class SymbolTable; class VariableWatchpointSet : public WatchpointSet { friend class LLIntOffsetsExtractor; public: VariableWatchpointSet(SymbolTable& symbolTable) : WatchpointSet(ClearWatchpoint) , m_symbolTable(symbolTable) { } ~VariableWatchpointSet() { } // For the purpose of deciding whether or not to watch this variable, you only need // to inspect inferredValue(). If this returns something other than the empty // value, then it means that at all future safepoints, this watchpoint set will be // in one of these states: // // IsWatched: in this case, the variable's value must still be the // inferredValue. // // IsInvalidated: in this case the variable's value may be anything but you'll // either notice that it's invalidated and not install the watchpoint, or // you will have been notified that the watchpoint was fired. JSValue inferredValue() const { return m_inferredValue.get(); } inline void notifyWrite(VM&, JSValue); void invalidate() { m_inferredValue.clear(); WatchpointSet::invalidate(); } void finalizeUnconditionally() { ASSERT(!!m_inferredValue == (state() == IsWatched)); if (!m_inferredValue) return; JSValue inferredValue = m_inferredValue.get(); if (!inferredValue.isCell()) return; JSCell* cell = inferredValue.asCell(); if (Heap::isMarked(cell)) return; invalidate(); } WriteBarrier<Unknown>* addressOfInferredValue() { return &m_inferredValue; } private: SymbolTable& m_symbolTable; WriteBarrier<Unknown> m_inferredValue; }; } // namespace JSC #endif // VariableWatchpointSet_h