Below is the main function for this assignment. Copy this into your file to start and change Name to your name. Stubs have been added for some of the functions so it will assemble.
.data num1: .word 0 num2: .word 0
text1: .asciiz "\nProduct " name: .asciiz "\nName" endline: .asciiz "\n"
.text
.globl main
main:
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lui $a0, 0x1001
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# get start of data
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addiu $a0, $a0, 0x0012
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# get start of name
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andi $a2, $a0, 0
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# set flag to false
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jal print
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# print name
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ori $s0, $0, 5
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# repeat 5 times
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top:
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beq $s0, $0, end
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# if counter is zero, stop loop
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lui $a0, 0x1001
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# set address of first word
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addiu $a1, $a0, 4
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# set address of second word
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jalgetinput
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# call function to get input, store into memory
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lui $t0, 0x1001
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# get address of first word
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lw $a0, 0($t0)
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# get the first value from memory
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lw $a1, 4($t0)
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# get the second value from memory
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jal multiply
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# multiply the values, result in $v0
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addi $a1, $v0, 0
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# get value to print from $v0
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lui $a0, 0x1001
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# get start of data section
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addi $a0, $a0, 8
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# get start of product output string
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ori $a2, $0, 1
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# set flag to true
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jal print
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# print result
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addi $s0, $s0, -1
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# decrement counter
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j top
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# repeat
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end: ori $v0, $0, 10
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# set command to stop program,
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syscall
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getinput: jr $ra
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#stub
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print: jr $ra
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#stub
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multiply: jr $ra
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#stub
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You are to complete the program by writing four functions. Pay particular attention to the purpose of each function, what registers to use and how the parameters and stack are to be used. If the instructions specify a particular register, then you must use it.
1. print
$a0 - address of a string to print
$a1 - value of an integer value to print
$a2 - boolean value (1 or 0)
This function must first print the string, then if $a2 holds a 1 (true) print the integer. Both outputs must be on the same line. End the output with a newline.
2. multiply
$a0 - first integer
$a1 - second integer
$v0 - first integer * second integer
This function is to calculate and return the result of multiplying the arguments together. You may assume that both arguments are greater than zero. As multiplication is really repeated addition, you can calculate the result by adding and using a loop. Using a version of the mult instruction is NOT ACCEPTABLE.
3. getpos
$a0 - prompt
$v0 - positive integer input
This function will print the prompt string by calling the print function (above) and then get input from the user. This process is repeated until a value greater than zero is input. The value is then returned in $v0. As this function calls another function so you MUSTsave the $ra on the stack (not into another register).
4. getinput
$a0 - address to store the first value
$a1 - address to store the second value
This function must call the getpos function two times and store each return value into the memory locations given in $a0 and $a1. As this function calls another function so you MUST save the $ra on the stack (not into another register).
General:
1. Do not use pseudo-instructions.
2. All calls to the functions must be done through jal and returns through jr.
3. Your code must be documented for each function. Describe which registers are used in the function and how they are used.
Submit your file with the complete program.