how does these two instruction mean?

["Bin Chen" <binary.chen@xxxxxxxxx>]

Hi,

In my program the gcc produce two lines of binary code:

100020e0:       ffc20000        sd      v0,0(s8)
100020e4:       dfc20000        ld      v0,0(s8)

first store v0->[s8], then load from [s8]->v0, why?

Thanks.

B.C