$3\mathrm{.}1$ Prime Number Detector

In task $2\mathrm{.}1,$ we saw how to perform multiplication via repeated add instructions, however, this becomes very slow for performing multiplications on large numbers. As such, the MIPS ISA supports special instructions for both multiplication and division, named mult and div.

These are special instructions, as they use special hardware to perform the operations, and the results of these instructions are always stored in the $HI$ and $LO$ registers. To access these $HI$ and $LO$ registers, two more special instructions are used: mfhi, to move from the $HI$ register into a GP register, and $mfl$ o$,$ to move from the LO register.

They can be used as follows: