Source/JavaScriptCore/runtime/JSImmutableButterfly.cpp

/*
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#include "config.h"
#include "JSImmutableButterfly.h"

#include "ButterflyInlines.h"

namespace JSC {

const ClassInfo JSImmutableButterfly::s_info = { "Immutable Butterfly"_s, nullptr, nullptr, nullptr, CREATE_METHOD_TABLE(JSImmutableButterfly) };

template<typename Visitor>
void JSImmutableButterfly::visitChildrenImpl(JSCell* cell, Visitor& visitor)
{
    ASSERT_GC_OBJECT_INHERITS(cell, info());
    Base::visitChildren(cell, visitor);
    if (!hasContiguous(cell->indexingType())) {
        ASSERT(hasDouble(cell->indexingType()) || hasInt32(cell->indexingType()));
        return;
    }

    Butterfly* butterfly = jsCast<JSImmutableButterfly*>(cell)->toButterfly();
    visitor.appendValuesHidden(butterfly->contiguous().data(), butterfly->publicLength());
}

DEFINE_VISIT_CHILDREN(JSImmutableButterfly);

void JSImmutableButterfly::copyToArguments(JSGlobalObject*, JSValue* firstElementDest, unsigned offset, unsigned length)
{
    for (unsigned i = 0; i < length; ++i) {
        if ((i + offset) < publicLength())
            firstElementDest[i] = get(i + offset);
        else
            firstElementDest[i] = jsUndefined();
    }
}

static_assert(JSImmutableButterfly::offsetOfData() == sizeof(JSImmutableButterfly), "m_header needs to be adjacent to Data");

} // namespace JSC