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Unformatted text preview: r runs (4) handler returns to next instruction Figure 8.5: Interrupt handling. The interrupt handler returns control to the next instruction in the application program’s control ﬂow. After the current instruction ﬁnishes executing, the processor notices that the interrupt pin has gone high, reads the exception number from the system bus, and then calls the appropriate interrupt handler. When the handler returns, it returns control to the next instruction (i.e., the instruction that would have followed the current instruction in the control ﬂow had the interrupt not occurred). The effect is that the program continues executing as though the interrupt had never happened. The remaining classes of exceptions (traps, faults, and aborts) occur synchronously as a result of executing the current instruction. We refer to this instruction as the faulting instruction. Traps
Traps are intentional exceptions that occur as a result of executing an instruction. Like interrupt handlers, trap handlers return control to the next instr...
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- Spring '10
- The American