Question

2. Translate the following C/Java code to MIPS assembly code. Assume that the values of a, i, and j are in registers $s0, $t0, and $t1, respectively. Assume that register $s2 holds the base address of the array A (add comments to your MIPS code). j = 0;

for(i=0 ; i<a ; i++)

A[i]=i+j++;

Answer 1

C Code:-

for (i=0;i<a; i++)
A[i] = i + j++;

MIPS Code:-

• MIPS is the short form for Microprocessor without Interlocked Pipelined Stages.
• It is a RISC (reduced instruction set computer) instruction set architecture,
• It is still used in many old networking equipment like switches, routers, modems, NICs and wireless APs/extenders.

# s0 --> a

# t0 --> i

# t1 -->  j

# s2 --> base address of array A, i.e. A[0]

# s3 --> A[i]

#START

li $t0,0 #load immediate $t0 with 0 We are assigning i=0

li $t1,0 #load immediate $t1 with 0 We are assigning j=0

loop: #for (i=0;i<a; i++)

bgt $t0, $s0, end # if $t0 > $s0, means if i>a then the loop moves to end.

lw $s3, 4($s2)   # here we load the contents of the word in to address of $s2. 4 is an offset here.

addi $t1, $t1, 1 # j++

  addi $s3, $t0, $t1 # A[i] = i + j++

addi $s2, $s2, 4   # next element A[i+1]

addi $t0, $t0, 1 # add 1 to $t0

j loop # jump back to the top

end:

syscall # End program