JSSegmentedVariableObject.cpp   [plain text]

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

#include "HeapSnapshotBuilder.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, JSValue initialValue)
{
    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(initialValue);
    
    return ScopeOffset(oldSize);
}

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

void JSSegmentedVariableObject::heapSnapshot(JSCell* cell, HeapSnapshotBuilder& builder)
{
    JSSegmentedVariableObject* thisObject = jsCast<JSSegmentedVariableObject*>(cell);
    Base::heapSnapshot(cell, builder);

    ConcurrentJITLocker locker(thisObject->symbolTable()->m_lock);
    SymbolTable::Map::iterator end = thisObject->symbolTable()->end(locker);
    for (SymbolTable::Map::iterator it = thisObject->symbolTable()->begin(locker); it != end; ++it) {
        SymbolTableEntry::Fast entry = it->value;
        ASSERT(!entry.isNull());
        ScopeOffset offset = entry.scopeOffset();
        if (!thisObject->isValidScopeOffset(offset))
            continue;

        JSValue toValue = thisObject->variableAt(offset).get();
        if (toValue && toValue.isCell())
            builder.appendVariableNameEdge(thisObject, toValue.asCell(), it->key.get());
    }
}

} // namespace JSC