Add call operand

bin/example.wasm

@@ -39,7 +39,7 @@ int $0;
 pushi $68; # D
 pushi $76; # L
 pushi $82; # R
-pushi $79; # O 
+pushi $79; # O
 pushi $87; # W
 
 seti %B $5;
@@ -72,17 +72,23 @@ seti %A [$1024];
 int $2;
 
 # Push the string "hell" into register A
-seti %A $108;
+seti %A $108;    # l
 shli %A $8 %A;
-addi %A $108 %A;
+addi %A $108 %A; # l
 shli %A $8 %A;
-addi %A $101 %A;
+addi %A $101 %A; # e
 shli %A $8 %A;
-addi %A $104 %A;
+addi %A $104 %A; # h
 
-# Store A at 900
+# Store A at memory location 900
 seti [$900] %A;
+
 # Setup to print a string from position 900
 seti %A $900;
 seti %B $4;
-int $3;
+int $3;
+
+# Jump over the interrupt
+call program_exit;
+int $3;
+program_exit: