Question

Problem #2 (20pts) Please write the MIPS assembly code corresponding to the following C code segment. Assume that f is assigned to register $s2 int Example int i, int j, int k) int f; f i+j-k-1: return fi

Answer 1

ScreenShot

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Program

#variable declaration
.data
       i: .asciiz "Please enter value of i:"
       j: .asciiz "Please enter value of j:"
       k: .asciiz "Please enter value of k:"
       f: .asciiz "f=i+j-k-1="
#main function
.text
.globl main
main:
       #prompt user for i value
       la $a0,i
       li $v0,4
       syscall
       #read i value
       li $v0,5
       syscall
       #store in a1
       move $a1,$v0
       #prompt user for j value
       la $a0,j
       li $v0,4
       syscall
       #read j value
       li $v0,5
       syscall
       #store in a2
       move $a2,$v0
       #prompt user for k value
       la $a0,k
       li $v0,4
       syscall
       #read i value
       li $v0,5
       syscall
       #store in a0
       move $a3,$v0
       #result prompt
       la $a0,f
       li $v0,4
       syscall
       #function call
       jal Example
       #result print
       move $a0,$v0
       li $v0,1
       syscall
       #exit
       li $v0,10
       syscall
#function definition
Example:
       #clear register s2 for f
       add $s2,$0,$0
       #s2=i+j
       add $s2,$a1,$a2
       #s2=i+j-k
       sub $s2,$s2,$a3
       #s2=i+j-k-1
       sub $s2,$s2,1
       #move value into v0 to return
       move $v0,$s2
       #return to main program
       jr $ra