Question

Solve the problems as directed. Each problem worth 15 points. Use the data declaration on the first page of this Review the SPIM program on the right. Then answer the following questions: What does the program do and how does it accomplish its goal? What is the last operation the program performs before halting? Write down the exact console output.. text main: la St1 str next Ib St0, (St1) beqz Sto, off sub Ssp, Ssp, 4 sw St0, (Ssp) addi St1, St1, 1 addi St2, St2, 1 j next off: sub St1, St1, 1. cap Iw St0, (Ssp) addi Ssp, Ssp, 4 bit St0, 0x61, getlet bgt St0, 0x7a, getlet sub St0, St0, 0x20 getlet: sb St0, 0(St1) sub St1, St1, 1 sub St2, St2, 1 beqz St2, over j cap over: la Sa0, str li Sv0, 4 syscall. Note ASCII Codes li Sv0, 10 syscall. data str .asciiz "hello world\n'' Note ASCII CODES: 0x30="0" 0x41="A" 0x5a="Z" 0x61="a" 0x7a="z" 0x30="0" 0x39="9" 0x 0a =\n (carriage return/line feed).

Answer 1

Solution: 1. The program converts the lower case letters given in string to upper case and displays it. It definesa procedure cap to convert into capital letters 2. The program checks whether each character in string is converted into upper case until end of string and it displays string before halting 3. The code is shown below: #De fine text section .text #De fine ma in method main: la Ştl, str #De fine next method next lb $t0, (Şt1) #Check if equal beqz Şto,off #Sub sub $sp, $sp, 4 #Store value #Add instruction addi $t1, Ştl,1 #Add instruction addi $t2, Şt2,1 #Jump to label j next #De fine off procedure off sub Ştl, Ştl,1 #De fine cap procedure

#Add instruction addi Şsp, $sp, 4 #Branch If less than blt Şt0, 0x61,getlet #Branch if greater than bgt $t0,0x7a, getlet #sub instruction sub Şt0, $t0,0x20 #De fine getlet procedure getlet sb $t0,0 (Ştl) #Sub instruction sub Şt1, $tl,1 #Sub instruction sub $t2, $t2,1 #Branch if matches beqz Şt2,over #Jump to label cap #De fine procedure over over: la Şa0,str #Load li $v0,4 #syscall syscall #Load li Sv0,10 #system call syscall

#Data data #Display string str: .asciiz "hello world \n'" Sample Output: HELLO WORLD -program is finished running --

Code:

#Define text section

.text

#Define main method

main: la $t1, str

#Define next method

next: lb $t0,($t1)

#Check if equal

beqz $t0,off

  

#Sub

sub $sp,$sp,4

  

#Store value

sw $t0,($sp)

  

#Add instruction

addi $t1,$t1,1

  

#Add instruction

addi $t2,$t2,1

  

#Jump to label

j next

   

#Define off procedure

off: sub $t1,$t1,1

   

#Define cap procedure

cap: lw $t0,($sp)

    

#Add instruction

addi $sp,$sp,4

    

#Branch if less than

blt $t0,0x61,getlet

     

#Branch if greater than

bgt $t0,0x7a,getlet

      

#sub instruction

sub $t0,$t0,0x20

      

   #Define getlet procedure

    getlet: sb $t0,0($t1)

      

    #Sub instruction

    sub $t1,$t1,1

      

    #Sub instruction

    sub $t2,$t2,1

    

    #Branch if matches

    beqz $t2,over

       

    #Jump to label

    j cap

       

     #Define procedure over

     over: la $a0,str

       

     #Load

     li $v0,4

       

     #Syscall

     syscall

       

     #Load

     li $v0,10

        

      #System call

      syscall

        

      #Data

      .data

      

       #Display string

        str: .asciiz "hello world \n"