Source/JavaScriptCore/runtime/VMEntryScope.cpp

/*
 * Copyright (C) 2013-2023 Apple Inc. All rights reserved.
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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#include "config.h"
#include "VMEntryScope.h"

#include "Options.h"
#include "SamplingProfiler.h"
#include "VM.h"
#include "VMEntryScopeInlines.h"
#include "WasmCapabilities.h"
#include "WasmMachineThreads.h"
#include "Watchdog.h"
#include <wtf/WTFConfig.h>

namespace JSC {

void VMEntryScope::setUpSlow()
{
    m_vm.entryScope = this;

    auto& thread = Thread::current();
    if (UNLIKELY(!thread.isJSThread())) {
        Thread::registerJSThread(thread);

        if (Wasm::isSupported())
            Wasm::startTrackingCurrentThread();
#if HAVE(MACH_EXCEPTIONS)
        if (g_wtfConfig.signalHandlers.initState == WTF::SignalHandlers::InitState::AddedHandlers)
            registerThreadForMachExceptionHandling(thread);
#endif
    }

    if (UNLIKELY(m_vm.hasAnyEntryScopeServiceRequest() || m_vm.hasTimeZoneChange()))
        m_vm.executeEntryScopeServicesOnEntry();
}

void VMEntryScope::tearDownSlow()
{
    ASSERT_WITH_MESSAGE(!m_vm.hasCheckpointOSRSideState(), "Exitting the VM but pending checkpoint side state still available");

    m_vm.entryScope = nullptr;

    if (UNLIKELY(m_vm.hasAnyEntryScopeServiceRequest()))
        m_vm.executeEntryScopeServicesOnExit();
}

} // namespace JSC