APPLICATION ARCHITECTURE

implements a "top of loop" test that allows the loop to be executed zero times.

2.3.3.3 Miscellaneous Instructions

The 80386 Bound instruction can be used to verify that an array subscript is within the bounds of the array. There are instructions for setting and clearing flags, and for loading and storing the status byte of the Flags register. The 80287 and 80387 supply the instructions that an operating system needs to initialize the coprocessor, handle coprocessor exceptions, and save and restore the coprocessor's state. Finally, of course, the 80386 has a No Opera- tion instruction.

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Intel 80386 manual Miscellaneous Instructions