Name: Box: Date:

HW23

(20 points) We wish to add a variant of the lw (load word) instruction, which increments the index register after loading the word from memory. This instruction (l_inc) corresponds to the following two instructions:

lw   $rt, L($rs)
addi $rs, $rs, 4

Add any necessary datapaths and control signals to the single-cycle datapath of Figure 4.17 on page 265 and show the necessary additions to Figure 4.18 on page 266.

  1. Write the RTL for this new instruction. It may be helpful to review the RTL on the course website.
  1. Adjust the datapth figure (attached) to execute your RTL.
  1. Provide an updated set of control signals for the new instruction.
Instruction name RegDst ALUSrc ALUOp MemtoReg RegWrite MemRead MemWrite Branch

Modify this figure for your instruction.