Design a MIPS processor supporting only the R-type and the jset rs, rt, rd instruction. The jset rs, rt, rd instruction does the following:

If rs is not equal to rt, the next PC is the memory content at rs-rt and rd is set to be rs-rt; otherwise, the next PC is PC+4 and register $ra is set to be PC+4.

Recall that $ra is the special register used in the jal instruction.

For example,

- if rs and rt are 20 and 8 respectively, rd will be 12, and PC will be the memory content at 12.

- if rs and rt are 20 and 20 respectively, rd will not be changed, PC will be PC+4, and $ra will be PC+4.

For this problem, assume that the opcode of R-type is 000000 and the opcode of jset is 100000.

- (30 points) Show the data path of this processor, add 2-1 MUX when necessary. Besides a group of wires, please show clearly the indices of the bits.

- (20 points) Consider the control signals for the 2-1 MUX. Please fill in the table (you should not need more than 4 2-1 MUXes). In case of "don’t care," write down 0. Then write down the logic functions. Certain bits in the instruction can be denoted as, for example, ins[31]. The ALU zero output can be referred to simply as "z."

R-type jset (rs != rt) jset (rs == rt)

MUXCtrl1

MUXCtrl2

MUXCtrl3

MUXCtrl4