Write a function in MIPS assembly by using the provided test_harness.s to complete the following requirements. Modify only the "Place your function here" part!

# test_harness.s

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

# PLACE YOUR FUNCTION HERE

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

.text

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

# DO NOT MODIFY BELOW THIS COMMENT

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

# Test harness

# Ask user to enter the hex string.

# Print the resulting integer, or report overflow.

# An empty string will terminate the program.

.data

# User prompt strings

prompt_str: .asciiz "Enter your hexadecimal string. Just hit enter to

quit: "

your_str: .asciiz "Your string: "

linefeed: .asciiz " "

dbl_linefeed: .asciiz " "

value_str: .asciiz "Value : "

overflow_str: .asciiz "Overflow detected! "

all_done_str: .asciiz " Good luck with your program!. Goodbye. "

hex_str_buf: # Space for input string from user.

.space 256

.text

.globl main

.globl convert_hex_str

main:

get_input_string:

# display prompt

li $v0,4 # code for print_string

la $a0,prompt_str # point $a0 to prompt string

syscall # print the string

# get the input string from the user

li $v0,8 # code for read_string

la $a0,hex_str_buf # $a0 - input buffer address

li $a1,256 # $a1 - Input buffer length

syscall # Get the string

# The string is NUL terminated.

la $s0,hex_str_buf # Save string in $s0

# SPIM puts a closing NEW LINE (ASCII 0xa) on the end of the string.

# We need to strip that off, since that is not a legal character in

our hex format.

# We just overwrite it with NUL (ASCII 0)

move $s1, $s0 # $s1 char pointer

strip_nl:

lbu $s2, ($s1) # $s2 Get the current character

beqz $s2, remove_nl

addi $s1, $s1, 1 # Next character

j strip_nl

remove_nl:

li $s2, 10 # Expected NL = ASCII 10 (0xa)

lbu $s3, -1($s1) # Character just before the NUL terminator

bne $s3, $s2, check_for_exit

li $s2, 0 # NUL Char (0)

sb $s2, -1($s1) # Wipe out NL

check_for_exit:

# Check if the input string is empty.

lbu $s2, ($s0) # Load first byte of the string.

beq $s2, $0, all_done # Exit if first byte is NUL terminator

# print result string

# - Prompt string

li $v0,4 # code for print_string

la $a0, your_str

syscall # print the string

# - The string

li $v0,4 # code for print_string

move $a0, $s0

syscall # print the string

# - LF

li $v0,4 # code for print_string

la $a0,linefeed # point $a0 to string

syscall # print the string

# Call Hex Converter

move $a0, $s0

jal convert_hex_str

move $s1, $v0 # Save value result in $s0

move $s2, $v1 # Save error result in $s1

beq $v1, $0, no_overflow

# - Overflow detected

# Print overflow message

li $v0,4

la $a0, overflow_str

syscall # print the string

j get_input_string # Repeat

# - Value

no_overflow:

# Print value message.

li $v0,4 # code for print_string

la $a0, value_str

syscall # print value prompt

li $v0,1 # code for print_int

move $a0, $s1

syscall # print the value itself.

li $v0,4

la $a0,dbl_linefeed

syscall # print the linefeed

j get_input_string # Repeat

# - Prompt string

li $v0,4 # code for print_string

la $a0, error_str

syscall # print the string

# All done, thank you!

all_done:

li $v0,4 # code for print_string

la $a0, all_done_str

syscall # print the string

li $v0,10 # code for exit

syscall # exit program

Requirements Your code must be well-commented to receive full credit. This means any non- trivial line of code should have an accompanying comment. For examples of appropriate comments, refer to any of the code examples on Canvas. Your function must be called convert hex str Your function must accept one input value, a pointer to the string, in register $ao. You must not modify the string during processing. Your function will return two values in two registers 1. 2. 3. 4. a. $v0: The converted integer value. It must contain an integer that corresponds to the value represented by the string passed to the function. The string is considered a hexadecimal representation of an unsigned integer that fits in 31 bits. $v1: An error status. 0 means no error. 1 means overflow error. If an error is returned, the integer value in Sv0 is ignored and can be any value. b. Your function should not invoke any syscalls, You do not need to print output or read keyboard input. That is all done by the test harness. 5. 6. The input string will consist of: a. Digit characters ('O-9) b. Hexadecimal letter characters, either upper or lower case ('a'-'f, 'A'-'F') A NUL terminator c. You may assume the input string follows this format. Your function will not be tested with improperly formatted strings, and there are no behavioral requirements if the string is not properly formatted. Overflow. You are returning a normal 32b signed twos-complement integer. Even though the value will always be non-negative, $vO uses signed form. What is the largest positive value that can be represented? If the input string represents a value larger than this, your function should report an error by returning 1 in $v1. 7. 8