add2.asm

#  http://codepad.org/BDXAySsj
#  https://pastebin.com/xhKiJHSG

# Daniel J. Ellard -- 02/21/94
# add2.asm -- A program that computes and prints the sum
#             of two numbers specified at runtime by the user.

# Registers used:
#           $t0 - used to hold the first number.
#           $t1 - used to hold the second number.
#           $t2 - used to hold the sum of the $t1 and $t2.
#           $v0 - syscall parameter and return value.
#           $a0 - syscall parameter.

main:
    ## Get first number from user, put into $t0.
    li $v0, 5           # load syscall read_int into $v0.
    syscall             # make the syscall.
    move $t0, $v0       # move the number read into $t0.


    ## Get second number from user, put into $t1.
    li $v0, 5           # load syscall read_int into $v0.
    syscall             # make the syscall.
    move $t1, $v0       # move the number read into $t1.
    add $t2, $t0, $t1   # compute the sum.


    ## Print out $t2.
    move $a0, $t2       # move the number to print into $a0.
    li $v0, 1           # load syscall print_int into $v0.
    syscall             # make the syscall.

exit:
    li $v0, 10          # syscall code 10 is for exit.
    syscall             # make the syscall.
# end of add2.asm.