Example Program

Here is a program that does that. There are better ways to load a register with a negative integer. However, this is a nice example of bit manipulation.

## handMadeNeg.asm
## 
## Program to demonstrate two's complement negative
##
## The program adds +146 to -82, leaving the result in $10

        .text
        .globl  main

main:
        ori      $7, $0, 146        # put +146 into $7
        ori      $8, $0,  82        # put 82 into $8
        nor      $8, $8,  $0        # reflect the bits for 82
        ori      $9, $0,   1        # add 1: 
        addu     $8, $8,  $9        # $8 now contains -82 in two's comp
        addu    $10, $7,  $8        # (+146) + (-82)

## End of file

Answer:

Example Program

QUESTION 8: