NtGetTickCount64 - NtDoc

#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)

FORCEINLINE
ULONGLONG
NtGetTickCount64(
    VOID
    )
{
    ULARGE_INTEGER tickCount;

#ifdef _WIN64

    tickCount.QuadPart = USER_SHARED_DATA->TickCountQuad;

#else

    while (TRUE)
    {
        tickCount.HighPart = (ULONG)USER_SHARED_DATA->TickCount.High1Time;
        tickCount.LowPart = USER_SHARED_DATA->TickCount.LowPart;

        if (tickCount.HighPart == (ULONG)USER_SHARED_DATA->TickCount.High2Time)
            break;

        YieldProcessor();
    }

#endif

    return (UInt32x32To64(tickCount.LowPart, USER_SHARED_DATA->TickCountMultiplier) >> 24) +
        (UInt32x32To64(tickCount.HighPart, USER_SHARED_DATA->TickCountMultiplier) << 8);
}

#endif
#endif
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