Question

Rewrite the loop from Exercise 2.29 to reduce the number of MIPS instructions executed

Short answer

The reduce number of Mips instructions are:

addi$\$t1,\$s0,400$

LOOP: lw$\$s1,0\left(\$t1\right)$

add$\$s2,\$s2,\$s1$

addi$\$t1,\$t1,-4$

bne $\$t1,\$s0,$LOOP

Step-by-step solution

MIPS instructions used in Exercise 2.29

addi: It is short for add immediate

lw: It is short for load word

add: It is an arithmetic operation used to add

slti: It is short for set on less than or equal

bne: it is short for the branch on not equal it test if registers are not equal

Step 2:Given MIPS instruction

addi$\$t1,\$0,\$0$

LOOP: lw$\$s1,0\left(\$s0\right)$

add$\$t2,\$s0,$

addi$\$s0,\$s0,4$

addi$\$t1,\$t1,1$

slti$\$t2,\$t1,100$

bne$\$t2,\$s0,$ LOOP

Rewrite the loop to Minimize the number of MIPS instruction

Here, we used variable only for loop control

Now, reduce the number of MIPS instruction

addi$\$t1,\$s0,400$ # add a constant number

LOOP: lw $\$s1,0\left(\$t1\right)$# load word

add $\$s2,\$s2,\$s1$# add first element

addi $\$t1,\$t1,-4$# add immediate and immediate means a constant no.

bne$\$t2,\$s0,$ LOOP #Loop until the pointer reaches limit