菜鸟求教mips archictecture设计

silverwolfman

刚开始做mips结构的processor，然后构架上面有一点不明白，为什么要在图中位置加一个shift left 2bits这个结构呢？偏移绝对地址的时候需要×4是为什么呢？有人接触过相同的设计么？可以解释一下么？谢谢！

示意图

lipizju

instruction length is 32bit, so the least 2 bits should always be zero, the offset in jump instruction omit the least significant two zero, so we should left shift 2 bits

like:   addr of inst0 in binary is 0000:         jump #10  in fact will jump to 1000 --> inst3   
          addr of inst1 in binary is 0100:         inst2
          addr of inst2 in binary is 1000:         inst3

silverwolfman

Thank you so much for the answer!  I've got it.

290058820

不断学习。