title: Attempt to execute non-instruction in mips assembler?
body: <pre><code>    .data
  stack: .word 3, 2
      .text
      .globl main
  main:
      la $s1, stack        #assign stack start memory to $s1
      addi $t3, $t3, 0     #clear $t3
      addi $t3, $t3, 4     #assign 4 to $t3
      add $s1, $s1, $t3    #second member of stack
      lw $t1, 0($s1)       #d2  
      addi $t3, $t3, -4    #move $t3 forward
      add $s1, $s1, $t3    #first member of stack
      lw $t0, 0($s1)       #d1
      add $t0, $t0, $t1    #d1 = d1 +d2
      sw $t0, 0($s1)       #store new d1 at d1's location
  </code></pre>
  
  <p>I'm trying to create a mips program, which gets last-1 and last member of the stack, and add them, and store it. I don't care about addi $t3, $t3, 4 or stack: .word 3, 2 it's just for test. </p>
  
  <p>However, when I run this at qtspim I got an error message "attempt to execute non-instruction at 0x0040004c" please enlighten me as to what the problem is.</p>