Question

For this assignment, you are required to write a MIPS program that reads its own instructions and counts the number of occurrences of each type of instruction (R-type, I-type, or J-type). To accomplish this task, your program should execute the following steps:

1. First, your program should load the address of its first instruction (0x400000) into a register, and initialize three separate instruction class counters to zero.
2. Next, your program should enter a loop that reads each instruction from memory. For each instruction, examine the “op code” field to determine whether it is an R-type, I-type, or J-type instruction, and increment the appropriate instruction class counter. (For the purpose of this assignment, you may assume that all instructions with an op code of 0 are R-type instructions; all instructions with an op code equal to either 2 or 3 are J-type instructions; and all other instructions are I-type instructions.)
3. Your source program’s final two instructions should be

       li           $v0, 10

       syscall

Thus, your program should repeat step 2’s loop until the machine instructions corresponding to this sequence are detected. (Be sure to count these machine instructions as well!)

4. Finally, save the values of your instruction class counters to variables declared in the data segment of your program. (For testing purposes, I recommend also using syscalls to display the three integer counts to the screen; if you do, be careful not to halt on these additional syscall instructions.)

THE SOLUTION FOR THIS ASSIGNMENT IS ACTUALLY ON CHEGG, BUT IT DOESN'T WORK. CAN YOU PLEASE HELP ME TO FIX THE ISSUE?

.data

#Inst: .#

CountR: .word 0
CountJ: .word 0
CountI: .word 0

CountR_char : .asciiz "CountR is "
CountJ_char : .asciiz "\nCountJ is "
CountI_char : .asciiz "\nCountI is "

TypeR: .word 0x00 #should be something like this but I don't know what exactly it should be
TypeJ1: .word 0x02
TypeJ2: .word 0x03

EndI: .word 0x2402000A #last but one instruction as last instruction is syscall and not unique

#first instruction is stored in memory location 0x00400000
#and second instruction is stored in location 0x00400004 and so on.
#Every instruction's type(op code) is stored as bit 31-26 in that 32bit

.text

main:

   lw $t0, CountR
   lw $t1, CountJ
   lw $t2, CountI
   lw $t4, TypeR
   lw $t5, TypeJ1
   lw $t6, TypeJ2
   li $t3, 0x00400000 #starting address
   li $s0, 0 #instruction code
   lw $t7, EndI

Loop: #read instruction at address into $s0

   lw $s0,0($t3) #Load complete word and rotate by right by 26
   #shift it right logical by 2 ,makes it 00xxxx, $s0= bit 31-26
   srl $s0,$s0,26
   # check shifted instruction
   beq $s0, $t4, typeR #if it's typeR, then jump to typeR
   beq $s0, $t5, typeJ #if it's typeJ1, then jump to typeJ
   beq $s0, $t6, typeJ #if it's typeJ2, then jump to typeJ

TypeI: #none of above, then it's typeI

   addi $t2, $t2, 1 #countI +1
   j Next #jump to next

typeR: # bit (31-26) is 0x00 (type r)
   addi $t0, $t0, 1 #countR +1
   j Next #jump to next

typeJ: # bit (31-26) is 0x02 or 0x03
   addi $t1, $t1, 1 #countJ +1
   j Next #jump to next

Next: #after count, check if it's end instruction
   lw $s0,0($t3)
   beq $s0,$t7,Exit #if it's endI, jump to exit

#not end yet, add address to get another instruction
   addi $t3,$t3,4 #address+4
   j Loop

Exit: #one last syscall instruction is remaining that is Type R, increment CountR
   addi $t0, $t0, 1 #countR +1 for syscall
   # store the result
   sw $t0,CountR
   sw $t1,CountJ
   sw $t2,CountI

#print result

#----------

   li $v0,4 #string print
   la $a0, CountR_char
   syscall
   li $v0,1
   add $a0, $t0 ,$0

   syscall
   li $v0,4 #string print

   la $a0, CountJ_char
   syscall

    li $v0,1
   add $a0, $t1 ,$0
   syscall

   li $v0,4 #string print
   la $a0, CountI_char
   syscall

   li $v0,1
   add $a0, $t2 ,$0
   syscall

   li $v0,10
   syscall

Answer 1

.data

#Inst: .#

CountR: .word 0

CountJ: .word 0

CountI: .word 0

CountR_char : .asciiz "CountR is "

CountJ_char : .asciiz "\nCountJ is "

CountI_char : .asciiz "\nCountI is "

TypeR: .word 0x00 #should be something like this but I don't know what exactly it should be

TypeJ1: .word 0x02

TypeJ2: .word 0x03

EndI: .word 0x2402000A #last but one instruction as last instruction is syscall and not unique

#first instruction is stored in memory location 0x00400000

#and second instruction is stored in location 0x00400004 and so on.

#Every instruction's type(op code) is stored as bit 31-26 in that 32bit

.text

main:

lw $t0, CountR

lw $t1, CountJ

lw $t2, CountI

lw $t4, TypeR

lw $t5, TypeJ1

lw $t6, TypeJ2

li $t3, 0x00400000 #starting address

li $s0, 0 #instruction code

lw $t7, EndI

Loop: #read instruction at address into $s0

lw $s0,0($t3) #Load complete word and rotate by right by 26

#shift it right logical by 2 ,makes it 00xxxx, $s0= bit 31-26

srl $s0,$s0,26

# check shifted instruction

beq $s0, $t4, typeR #if it's typeR, then jump to typeR

beq $s0, $t5, typeJ #if it's typeJ1, then jump to typeJ

beq $s0, $t6, typeJ #if it's typeJ2, then jump to typeJ

TypeI: #none of above, then it's typeI

addi $t2, $t2, 1 #countI +1

j Next #jump to next

typeR: # bit (31-26) is 0x00 (type r)

addi $t0, $t0, 1 #countR +1

j Next #jump to next

typeJ: # bit (31-26) is 0x02 or 0x03

addi $t1, $t1, 1 #countJ +1

j Next #jump to next

Next: #after count, check if it's end instruction

lw $s0,0($t3)

beq $s0,$t7,Exit #if it's endI, jump to exit

#not end yet, add address to get another instruction

addi $t3,$t3,4 #address+4

j Loop

Exit: #one last syscall instruction is remaining that is Type R, increment CountR

addi $t0, $t0, 1 #countR +1 for syscall

# store the result

sw $t0,CountR

sw $t1,CountJ

sw $t2,CountI

#print result

#----------

li $v0,4 #string print

la $a0, CountR_char

syscall

li $v0,1

add $a0, $t0 ,$0

syscall

li $v0,4 #string print

la $a0, CountJ_char

syscall

li $v0,1

add $a0, $t1 ,$0

syscall

li $v0,4 #string print

la $a0, CountI_char

syscall

li $v0,1

add $a0, $t2 ,$0

syscall

#------------

li $v0,10

syscall

I have made the necessary modifications and print the results using the system call.