diff --git a/include/aefa_opcodes.hrl b/include/aefa_opcodes.hrl
index c52016e..abc189e 100644
--- a/include/aefa_opcodes.hrl
+++ b/include/aefa_opcodes.hrl
@@ -7,7 +7,7 @@
 -define('CALL_T'         , 16#04).
 -define('CALL_TR'        , 16#05).
 -define('JUMP'           , 16#06).
--define('JUMPI'          , 16#07).
+-define('JUMPIF'         , 16#07).
 -define('SWITCH'         , 16#08).
 -define('PUSH'           , 16#09).
 -define('DUP'            , 16#0a).
diff --git a/src/aefa_asm.erl b/src/aefa_asm.erl
index bcf370d..0d6f1e9 100644
--- a/src/aefa_asm.erl
+++ b/src/aefa_asm.erl
@@ -217,7 +217,7 @@ deserialize_op(Op, Rest, Code) ->
     end.
 
 
-serialize(#{functions := Functions} = Env) ->
+serialize(#{functions := Functions} =_Env) ->
     Code = [[?FUNCTION, Name, serialize_signature(Sig), C]  ||
                {Name, {Sig, C}} <- maps:to_list(Functions)],
     serialize_code(lists:flatten(Code)).
@@ -419,25 +419,13 @@ to_list_of_types(Tokens) ->
     case to_type(Tokens) of
         {Type, [{',', _} |  Rest]} ->
             {MoreTypes, Rest2} = to_list_of_types(Rest),
-            {[Type|MoreTypes], Rest2};
+            {[Type|MoreTypes], Rest2}
         {Type, [{']', _} |  Rest]} ->
             {[Type], Rest}
     end.
 
 
 
-%% Also reverses the code (back to unreversed state).
-resolve_refs([{ref, ID} | Rest], Env, Code) ->
-    Address = maps:get(ID, Env),
-    resolve_refs(Rest, Env, [Address | Code]);
-resolve_refs([Op | Rest], Env, Code) ->
-    resolve_refs(Rest, Env, [Op | Code]);
-resolve_refs([],_Env, Code) -> Code.
-
-expand_args([OP | Rest]) ->
-    [OP | expand_args(Rest)];
-expand_args([]) -> [].
-
 insert_fun(none, [], Env) -> Env;
 insert_fun({Name, Type, RetType}, Code, #{functions := Functions} = Env) ->
     {Hash, Env2} = insert_symbol(Name, Env),
diff --git a/src/aefa_asm_scan.xrl b/src/aefa_asm_scan.xrl
index 50a2575..84168e5 100644
--- a/src/aefa_asm_scan.xrl
+++ b/src/aefa_asm_scan.xrl
@@ -34,7 +34,7 @@ CALL_R         : {token, {mnemonic, TokenLine, 'CALL_R'}}.
 CALL_T         : {token, {mnemonic, TokenLine, 'CALL_T'}}.
 CALL_TR        : {token, {mnemonic, TokenLine, 'CALL_TR'}}.
 JUMP           : {token, {mnemonic, TokenLine, 'JUMP'}}.
-JUMPI          : {token, {mnemonic, TokenLine, 'JUMPI'}}.
+JUMPIF         : {token, {mnemonic, TokenLine, 'JUMPIF'}}.
 SWITCH         : {token, {mnemonic, TokenLine, 'SWITCH'}}.
 
 PUSH           : {token, {mnemonic, TokenLine, 'PUSH'}}.
diff --git a/src/aefa_opcodes.erl b/src/aefa_opcodes.erl
index f63fee9..89e44d4 100644
--- a/src/aefa_opcodes.erl
+++ b/src/aefa_opcodes.erl
@@ -28,12 +28,18 @@ mnemonic(?NOP)         -> 'NOP'        ;
 mnemonic(?RETURN)      -> 'RETURN'     ;
 mnemonic(?PUSH)        -> 'PUSH'       ;
 mnemonic(?JUMP)        -> 'JUMP'       ;
+mnemonic(?JUMPIF)      -> 'JUMPIF'     ;
 mnemonic(?INC)         -> 'INC'        ;
 mnemonic(?CALL)        -> 'CALL'       ;
 mnemonic(?CALL_T)      -> 'CALL_T'     ;
 mnemonic(?CALL_R)      -> 'CALL_R'     ;
 mnemonic(?CALL_TR)     -> 'CALL_TR'    ;
 mnemonic(?ADD)         -> 'ADD'        ;
+mnemonic(?SUB)         -> 'SUB'        ;
+mnemonic(?MUL)         -> 'MUL'        ;
+mnemonic(?DIV)         -> 'DIV'        ;
+mnemonic(?MOD)         -> 'MOD'        ;
+mnemonic(?POW)         -> 'POW'        ;
 mnemonic(?AND)         -> 'AND'        ;
 mnemonic(?OR)          -> 'OR'         ;
 mnemonic(?NOT)         -> 'NOT'        ;
@@ -50,8 +56,14 @@ m_to_op('COMMENT')     -> ?COMMENT("") ;
 m_to_op('RETURN')      -> ?RETURN      ;
 m_to_op('PUSH')        -> ?PUSH        ;
 m_to_op('JUMP')        -> ?JUMP        ;
+m_to_op('JUMPIF')      -> ?JUMPIF      ;
 m_to_op('INC')         -> ?INC         ;
 m_to_op('ADD')         -> ?ADD         ;
+m_to_op('SUB')         -> ?SUB         ;
+m_to_op('MUL')         -> ?MUL         ;
+m_to_op('DIV')         -> ?DIV         ;
+m_to_op('MOD')         -> ?MOD         ;
+m_to_op('POW')         -> ?POW         ;
 m_to_op('AND')         -> ?AND         ;
 m_to_op('OR')          -> ?OR          ;
 m_to_op('NOT')         -> ?NOT         ;
@@ -69,14 +81,23 @@ m_to_op('CALL_TR')     -> ?CALL_TR     .
 args(?NOP)     -> 0;
 args(?RETURN)  -> 0;
 args(?INC)     -> 0;
+
 args(?PUSH)    -> 1;
 args(?JUMP)    -> 1;
 args(?CALL)    -> 1;
 args(?CALL_T)  -> 1;
+
+args(?JUMPIF)  -> 2;
 args(?CALL_R)  -> 2;
 args(?CALL_TR) -> 2;
 args(?NOT)     -> 2;
+
 args(?ADD)     -> 3;
+args(?SUB)     -> 3;
+args(?MUL)     -> 3;
+args(?DIV)     -> 3;
+args(?MOD)     -> 3;
+args(?POW)     -> 3;
 args(?AND)     -> 3;
 args(?OR)      -> 3;
 args(?LT)      -> 3;
@@ -89,6 +110,7 @@ args(_) -> 0. %% TODO do not allow this
 
 end_bb(?RETURN) -> true;
 end_bb(?JUMP)   -> true;
+end_bb(?JUMPIF) -> true;
 end_bb(?CALL)   -> true;
 end_bb(?CALL_T) -> true;
 end_bb(?CALL_R) -> true;