Regs0 0 userregsxp userregsxp 4 scheduler recall

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Unformatted text preview: Regs[0] = User.Regs[0] – 1; if (User.Regs[0] != 0) { User.Regs[XP] = User.Regs[XP] – 4; Scheduler(); } } Recall that the C operator != means “not equal”. Your task is to provide documentation explaining, to an application developer, the impact of executing this SVC on a running application and on other processes running on the system. (A) (3 points) Describe, in few sentences, the effect of executing this mystery SVC by an application. Be sure to mention the role of and impact on any relevant register contents. This SVC causes the current process to “sleep” (not execute any further instructions) for the next R0 - 1 scheduler cycles. R0 will be set to 0 when the SVC completes. If R0 is 1, it has no effect beyond setting R0 to 0. We gave full credit (3 points) for all answers that included at least the first sentence. (Brief documentation of mystery SVC) END OF QUIZ! (phew!) 6.004 Spring 2009 - 4 of 4 - Quiz #4...
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