title: Negative numbers in ARM assembly
body: <p>I'm currently struggling with how to use negative numbers in ARM assembly. Let's say I have a simple code like this:</p>
  
  <pre><code>MOV R0, #0
  SUB R0, R0, #1
  SWI 4
  </code></pre>
  
  <p><code>R0</code> will obviously store the value <code>0xFFFFFFFF</code>, but <code>SWI</code> doesn't seem to treat it as a signed integer and so the number that gets displayed is 4294967295. How can I print out -1?</p>