A coroutine call instruction.The instruction pops the top of stack into temporary register, pushes program counter onto the stack, and then puts the saved top of stack in the program counter.
一种同程序访问指令,该指令把
顶弹入临时寄存器,把程序计数器推入
内,然后把保存的
顶内容存入到程序计数器内。