.data
varA:   .word   42
str1:   .asciiz "\n"

        .text
        .globl main
main:
        subu    $sp, $sp, 32    #
        sw      $ra, 28($sp)    # save return address
        sw      $fp, 24($sp)    # save previous frame pointer (ebp)
        sw      $s0, 20($sp)    # preserve $s0
        sw      $s1, 16($sp)    # preserve $s1

        lw      $s0, varA   # load varA value into $s0

        addi    $s1, $0, 31     # $s1 holds the constant 31
        # Before Calling
        add     $a0, $0, $s0    # varA is an argv
        jal     MYADD       # jump & link
        # Return from MYADD
        add     $s1, $0, $v0    # $s1 holds returned value

        li      $v0, 1      # syscall "integer"
        add     $a0, $0, $s1    # put sum in syscall
        syscall

        li      $v0, 4      # syscall "print_string"
        la      $a0, str1   # put str1 in syscalll
        syscall

        li      $v0, 1      # syscall "integer"
        add     $a0, $0, $s0    # put varA in syscall
        syscall

        lw      $s1, 16($sp)    # restore s1
        lw      $s0, 20($sp)    # restore s0
        lw      $fp, 24($sp)    # restore old frame pointer
        lw      $ra, 28($sp)    # restore return address
        jr      $ra

MYADD:
        subu    $sp, $sp, 32    #
        sw      $ra, 28($sp)    # save return address
        sw      $fp, 24($sp)    # save previous frame pointer (ebp)
        sw      $s0, 20($sp)    # preserve $s0, varA = 42
        sw      $s1, 16($sp)    # preserve $s1, sum = 31

        li      $s1, 1      # t = 1
        add     $s0, $a0, $s1   # x = x + t  (use $s0 to store sum)
        add     $v0, $0, $s0    # add x to result register

        lw      $s1, 16($sp)    # restore s1
        lw      $s0, 20($sp)    # restore s0
        lw      $fp, 24($sp)    # restore old frame pointer
        lw      $ra, 28($sp)    # restore return address
        j       $ra