Jump instruction
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A jump instruction is an instruction in a programming language, most commonly referring to an assembly language CPU instruction that takes a memory address as an argument and upon execution the path of control goes to that address to find more CPU instructions to execute. In assembly this argument is specified as a label that can be some variable word. In machine language this label gets translated by the assembler to some memory path(e.g. 0xFF45B4D1). An example would be as follows.
Start: mov %a1,0x61 add a1,a2 jmp Start
The "Start:" is a label. "Start" refers to the memory address where the next instruction ("mov a1, 0x61") is at. On execution the CPU would move the value of 0x61 into a1 (which is an address register), then add the contents a1 and a2, and on the jump instruction ("jmp Start") the CPU would go to the memory address "Start" where it would continue to execute the next instruction it found ("mov a1, 0x61").