Source/JavaScriptCore/runtime/JSSegmentedVariableObject.cpp

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#include "config.h"
#include "JSSegmentedVariableObject.h"

#include "JSCInlines.h"

namespace JSC {

ScopeOffset JSSegmentedVariableObject::findVariableIndex(void* variableAddress)
{
    ConcurrentJITLocker locker(m_lock);
    
    for (unsigned i = m_variables.size(); i--;) {
        if (&m_variables[i] != variableAddress)
            continue;
        return ScopeOffset(i);
    }
    CRASH();
    return ScopeOffset();
}

ScopeOffset JSSegmentedVariableObject::addVariables(unsigned numberOfVariablesToAdd)
{
    ConcurrentJITLocker locker(m_lock);
    
    size_t oldSize = m_variables.size();
    m_variables.grow(oldSize + numberOfVariablesToAdd);
    
    for (size_t i = numberOfVariablesToAdd; i--;)
        m_variables[oldSize + i].setWithoutWriteBarrier(jsUndefined());
    
    return ScopeOffset(oldSize);
}

void JSSegmentedVariableObject::visitChildren(JSCell* cell, SlotVisitor& slotVisitor)
{
    JSSegmentedVariableObject* thisObject = jsCast<JSSegmentedVariableObject*>(cell);
    ASSERT_GC_OBJECT_INHERITS(thisObject, info());
    JSSymbolTableObject::visitChildren(thisObject, slotVisitor);
    
    for (unsigned i = thisObject->m_variables.size(); i--;)
        slotVisitor.append(&thisObject->m_variables[i]);
}

} // namespace JSC