----------------------------------------
- Simple Code Generation Example 1     -
- (based on the Final Project grammar) -
----------------------------------------

Source code:
{
   int i
   i = 5 
   print(i)
}
$

int i makes an entry into the stack temp table, aliasing i with location t0 xx.  If 
      we are being nice, then we could initialize i to 0 with the following code:
      A9 00 8D t0 xx.  (LDA 0, STA t0xx)

i=5 turns into A9 05 8D T0 XX (remember, t0xx will be replaced by a real value later.)

00: A9 00 8D T0 XX A9 05 8D  
08: t0 xx .. .. .. .. .. .. 
10: .. .. .. .. .. .. .. .. 

print(i) adds AC T0 XX A2 01 FF to the opcode stream

00: A9 00 8D t0 xx A9 05 8D  
08: t0 xx AC t0 xx A2 01 FF 
10: .. .. .. .. .. .. .. .. 

Then let's put a break (00) at the end.

00: A9 00 8D T0 XX A9 05 8D  
08: T0 XX AC T0 XX A2 01 FF 
10: 00 .. .. .. .. .. .. .. 

Now we can see that we can begin the stack area at location 0x11.
In the little endian convention, that's 11 00.  Backpatch that into the code.

00: A9 00 8D 11 00 A9 05 8D  
08: 11 00 AC 11 00 A2 01 FF 
10: 00 .. .. .. .. .. .. .. 

And we're done.  Looking at it as a stream: A9 00 8D 11 00 A9 05 8D 11 00 AC 11 00 A2 01 FF 00 

Try that in an OS on our class site.