So this instruction stores the link register (which holds the return address) into the proper location in the calling function's stack frame.
所以该指令会将链接寄存器(存有返回地址)存储到调用函数堆栈框架的恰当位置。
3
Since you did not call any functions or use any local storage, you did not need a stack frame at all, so you can now just exit through the link register.