如何在MIPS Assembly中将二进制字符串转换为其2的补码？

Question

我有一个MIPS汇编程序，该程序从用户输入中获取负整数，找到该数字的绝对值，然后将其转换为二进制字符串。我希望能够通过翻转计算的二进制字符串来找到数字的2的补码（将所有0更改为1，将1更改为0），然后将1添加到最低有效位（同时携带1到更高的位）位（如果需要）。我不确定如何执行此操作。任何帮助将不胜感激。我在下面发布了我当前的程序以供参考

.data
  #declare strings
  readMsg: asciiz "Enter a negative number:"
  printBinary: .asciiz "Binary Number :"
  space: .asciiz " "
  outOfRange: .asciiz "number is not negative!"

 .text
 .globl main
 main:
    #prompt the user to enter a negative number
    li $v0, 4
    la $a0, readMsg
    syscall
    #read integer from the user
    li $v0, 5
    syscall

    #if user input is positive, exit. if negative, find absolute value and continue
    bgt $v0, $zero, exit
    sub $v0, $zero, $v0
    blt $v0, $zero, continue

    continue:
      #move to input value to register $s0
      move $s0, $v0
      #print the string binary number
      li $v0, 4
      la $a0, printBinary
      syscall

    #jump and link to the calculateBinary
    jal calculateBinary
    #end the program
    li $v0, 10
    syscall

    #calculate the binary string of integer
    calculateBinary:
      #move input $s0 into $t0
      add $t0, $zero, $s0
      #move 0 into $t1
      add $t1, $zero, $zero
      #load 1 as a mask
      addi $t3, $zero, 1
      #shift  left the value of $t3 by 7 positions
      sll $t3, $t3, 7
      addi $t4, $zero, 8 #loop counter

      #perform AND with input and mask
    loop:
      and $t1, $t0, $t3
      #branch to print if 0
      beq $t1, $zero, printBinValue
      #move 0 into $t1
      add $t1, $zero, $zero
      #put a 1 in $t1
      addi $t1, $zero, 1
      j printBinValue

    printBinValue:
       #print value
       li $v0, 1
       move $a0, $t1
       syscall
       #putspace
       beq $t4, 5, printSpace
       j loop2

    printSpace:
      li $v0, 4
      la $a0, space
      syscall

    loop2:
      #shift right by 1 position
      srl $t3, $t3, 1
      addi $t4, $t4, -1
      bne $t4, $zero, loop
      #return to main
      jr $ra

     exit:
       li $v0, 4
       la $a0, outOfRange
       syscall