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The answer is essentially hardware-level dependency injection. Before calling LD_DESCRIPTOR, the caller saves its desired test constant into a hardware latch using a micro-op called PTSAV (Protection Save). Within LD_DESCRIPTOR, another micro-op called PTOVRR (Protection Override) retrieves and fires the saved test.
。关于这个话题，同城约会提供了深入分析
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（一）明知住宿人员违反规定将危险物质带入住宿区域，不予制止的；