Added error codes to emitError Function

src/main/java/chocopy/pa3/CodeGenImpl.java

@@ -1192,6 +1192,10 @@ public class CodeGenImpl extends CodeGenBase
         backend.emitGlobalLabel(errLabel);
         if(errLabel==errorOob)
             backend.emitLI(A0, ERROR_OOB, "Exit code for: " + msg);
+        else if(errLabel==errorDiv)
+            backend.emitLI(A0, ERROR_DIV_ZERO, "Exit code for: " + msg);
+        else if(errLabel==errorNI)
+            backend.emitLI(A0, ERROR_NYI, "Exit code for: " + msg);    
         else    
             backend.emitLI(A0, ERROR_NONE, "Exit code for: " + msg);
         backend.emitLA(A1, constants.getStrConstant(msg), "Load error message as str");