diff --git a/src/libcoreint/interpreter.c b/src/libcoreint/interpreter.c
index 0c96e0b81..d841fdf6f 100644
--- a/src/libcoreint/interpreter.c
+++ b/src/libcoreint/interpreter.c
@@ -18,8 +18,6 @@
 void
 gen_bytecode ()
 {
-  __int_data.pos = 0;
-
   /*
    while (true) {
     LEDToggle (LED3);
@@ -34,12 +32,12 @@ gen_bytecode ()
     wait(500);
    }
    */
-  save_op_data (getop_loop_inf (1));
-  save_op_data (getop_call_1 (0, 12));
-  save_op_data (getop_call_1 (0, 13));
-  save_op_data (getop_call_1 (0, 14));
-  save_op_data (getop_call_1 (0, 15));
-  save_op_data (getop_jmp (0));
+  save_op_data (0, getop_loop_inf (1));
+  save_op_data (1, getop_call_1 (0, 12));
+  save_op_data (2, getop_call_1 (0, 13));
+  save_op_data (3, getop_call_1 (0, 14));
+  save_op_data (4, getop_call_1 (0, 15));
+  save_op_data (5, getop_jmp (0));
 
 #ifdef __MCU
   // It's mandatory to restart app!
@@ -50,10 +48,9 @@ gen_bytecode ()
 void
 init_int ()
 {
-#define INIT_OP_FUNC(name) __int_data.func[ name ] = opfunc_##name ;
+#define INIT_OP_FUNC(name) __opfuncs[ name ] = opfunc_##name ;
   JERRY_STATIC_ASSERT (sizeof (OPCODE) <= 4);
 
-  __int_data.pos = 0;
   OP_LIST (INIT_OP_FUNC)
 }
 
@@ -62,9 +59,18 @@ run_int ()
 {
   init_int ();
 
+  struct __int_data int_data;
+  int_data.pos = 0;
+
   while (true)
   {
-    OPCODE *curr = &__program[__int_data.pos];
-    __int_data.func[curr->op_idx](*curr);
+    run_int_from_pos(&int_data);
   }
 }
+
+void
+run_int_from_pos (struct __int_data *int_data)
+{
+  OPCODE *curr = &__program[int_data->pos];
+  __opfuncs[curr->op_idx](*curr, int_data);
+}
diff --git a/src/libcoreint/interpreter.h b/src/libcoreint/interpreter.h
index 545939d76..01916337f 100644
--- a/src/libcoreint/interpreter.h
+++ b/src/libcoreint/interpreter.h
@@ -26,14 +26,17 @@
 
 OPCODE __program[128];
 
-struct {
-    int pos;
-    opfunc func[LAST_OP];
-    int *root_op_addr;
-} __int_data;
+opfunc __opfuncs[LAST_OP];
 
-void gen_bytecode();
-void run_int();
+struct __int_data
+{
+  int pos;
+  int *root_op_addr;
+};
+
+void gen_bytecode ();
+void run_int ();
+void run_int_from_pos (struct __int_data *);
 
 #endif	/* INTERPRETER_H */
 
diff --git a/src/libcoreint/opcode-structures.h b/src/libcoreint/opcode-structures.h
index 592c27377..3416e012f 100644
--- a/src/libcoreint/opcode-structures.h
+++ b/src/libcoreint/opcode-structures.h
@@ -17,7 +17,12 @@
 #define	OPCODE_STRUCTURES_H
 
 // Jerry bytecode ver:07/04/2014 
-#define OP_DEF(name, list) struct __op_##name { list ;  }
+#define OP_DEF(name, list) struct __op_##name { list ;  } ;
+
+
+#define OP_CODE_DECL_VOID(name) \
+        struct __op_##name { }; \
+        OPCODE getop_##name ();
 
 #define OP_CODE_DECL(name, type, ... ) \
         OP_DEF (name, type##_DECL( __VA_ARGS__ ) ); \
@@ -321,6 +326,7 @@ OP_CODE_DECL (varg_3_end, T_IDX_IDX_IDX,
 /** return value; */
 OP_CODE_DECL (retval, T_IDX,
               ret_value);
+OP_CODE_DECL_VOID (ret);
 
 // LOOPS
 // Lately, all loops should be translated into different JMPs in an optimizer.
@@ -363,7 +369,6 @@ OP_CODE_DECL (loop_postcond, T_IDX_IDX,
               condition,
               body_root);
 
-//// TODO
 ///** for vars...in iter, state, ctl */
 //OP_CODE_DECL (loop_init, T_IDX_IDX_IDX,             
 //              start_idx, stop_idx, step_idx);
@@ -374,6 +379,7 @@ OP_CODE_DECL (loop_postcond, T_IDX_IDX,
 //OP_CODE_DECL (loop_cond_pre_end, T_IDX,             
 //              iterator, body_root);
 
+// Property accessors (array, objects, strings)
 /** Array ops for ILMIR*/
 //OP_CODE_DECL (array_copy, T_IDX_IDX,                /** L = R */
 //              var_left, var_right);
@@ -382,5 +388,15 @@ OP_CODE_DECL (loop_postcond, T_IDX_IDX,
 //OP_CODE_DECL (array_get, T_IDX_IDX_IDX,             /** dst = array[index] */
 //              dst, array, index);
 
+//// TODO
+
+// Variable declarations
+// TODO New constructor
+
+
+
+
+
+
 #endif	/* OPCODE_STRUCTURES_H */
 
diff --git a/src/libcoreint/opcodes.c b/src/libcoreint/opcodes.c
index 4eb2f9ec1..50b2e1070 100644
--- a/src/libcoreint/opcodes.c
+++ b/src/libcoreint/opcodes.c
@@ -18,100 +18,101 @@
 #include "interpreter.h"
 
 void
-save_op_data (OPCODE opdata)
+save_op_data (int pos, OPCODE opdata)
 {
-  __program[__int_data.pos++] = opdata;
+  __program[pos] = opdata;
 }
 
-void opfunc_loop_init_num (OPCODE opdata) { unreachable (); }
-void opfunc_loop_precond_begin_num (OPCODE opdata) { unreachable (); }
-void opfunc_loop_precond_end_num (OPCODE opdata) { unreachable (); }
-void opfunc_loop_postcond (OPCODE opdata) { unreachable (); }
-void opfunc_call_2 (OPCODE opdata) { unreachable (); }
-void opfunc_call_n (OPCODE opdata) { unreachable (); }
-void opfunc_func_decl_1 (OPCODE opdata) { unreachable (); }
-void opfunc_func_decl_2 (OPCODE opdata) { unreachable (); }
-void opfunc_func_decl_n (OPCODE opdata) { unreachable (); }
-void opfunc_varg_1 (OPCODE opdata) { unreachable (); }
-void opfunc_varg_1_end (OPCODE opdata) { unreachable (); }
-void opfunc_varg_2 (OPCODE opdata) { unreachable (); }
-void opfunc_varg_2_end (OPCODE opdata) { unreachable (); }
-void opfunc_varg_3 (OPCODE opdata) { unreachable (); }
-void opfunc_varg_3_end (OPCODE opdata) { unreachable (); }
-void opfunc_retval (OPCODE opdata) { unreachable (); }
-void opfunc_assignment (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_multiplication (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_devision (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_remainder (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_addition (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_substruction (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_shift_left (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_shift_right (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_shift_uright (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_b_and (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_b_xor (OPCODE opdata) { unreachable (); }
-void opfunc_assignment_b_or (OPCODE opdata) { unreachable (); }
-void opfunc_logical_and (OPCODE opdata) { unreachable (); }
-void opfunc_logical_or (OPCODE opdata) { unreachable (); }
-void opfunc_b_and (OPCODE opdata) { unreachable (); }
-void opfunc_b_or (OPCODE opdata) { unreachable (); }
-void opfunc_b_xor (OPCODE opdata) { unreachable (); }
-void opfunc_b_shift_left (OPCODE opdata) { unreachable (); }
-void opfunc_b_shift_right (OPCODE opdata) { unreachable (); }
-void opfunc_b_shift_uright (OPCODE opdata) { unreachable (); }
-void opfunc_addition (OPCODE opdata) { unreachable (); }
-void opfunc_substraction (OPCODE opdata) { unreachable (); }
-void opfunc_division (OPCODE opdata) { unreachable (); }
-void opfunc_multiplication (OPCODE opdata) { unreachable (); }
-void opfunc_remainder (OPCODE opdata) { unreachable (); }
-void opfunc_jmp_up (OPCODE opdata) { unreachable (); }
-void opfunc_jmp_down (OPCODE opdata) { unreachable (); }
-void opfunc_is_true_jmp (OPCODE opdata) { unreachable (); }
-void opfunc_is_false_jmp (OPCODE opdata) { unreachable (); }
-void opfunc_is_less_than (OPCODE opdata) { unreachable (); }
-void opfunc_is_less_or_equal (OPCODE opdata) { unreachable (); }
-void opfunc_is_greater_than (OPCODE opdata) { unreachable (); }
-void opfunc_is_greater_or_equal (OPCODE opdata) { unreachable (); }
-void opfunc_is_equal_value (OPCODE opdata) { unreachable (); }
-void opfunc_is_not_equal_value (OPCODE opdata) { unreachable (); }
-void opfunc_is_equal_value_type (OPCODE opdata) { unreachable (); }
-void opfunc_is_not_equal_value_type (OPCODE opdata) { unreachable (); }
+void opfunc_loop_init_num (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_loop_precond_begin_num (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_loop_precond_end_num (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_loop_postcond (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_call_2 (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_call_n (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_func_decl_1 (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_func_decl_2 (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_func_decl_n (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_varg_1 (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_varg_1_end (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_varg_2 (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_varg_2_end (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_varg_3 (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_varg_3_end (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_retval (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_ret (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_multiplication (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_devision (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_remainder (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_addition (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_substruction (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_shift_left (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_shift_right (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_shift_uright (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_b_and (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_b_xor (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_assignment_b_or (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_logical_and (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_logical_or (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_b_and (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_b_or (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_b_xor (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_b_shift_left (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_b_shift_right (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_b_shift_uright (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_addition (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_substraction (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_division (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_multiplication (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_remainder (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_jmp_up (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_jmp_down (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_true_jmp (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_false_jmp (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_less_than (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_less_or_equal (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_greater_than (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_greater_or_equal (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_equal_value (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_not_equal_value (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_equal_value_type (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
+void opfunc_is_not_equal_value_type (OPCODE opdata, struct __int_data *int_data) { unreachable (); }
 
 void
-opfunc_loop_inf (OPCODE opdata)
+opfunc_loop_inf (OPCODE opdata, struct __int_data *int_data)
 {
 #ifdef __HOST
   printf ("%d::loop_inf:idx:%d\n",
-          __int_data.pos,
+          int_data->pos,
           opdata.data.loop_inf.loop_root);
 #endif
 
-  __int_data.pos = opdata.data.loop_inf.loop_root;
+  int_data->pos = opdata.data.loop_inf.loop_root;
 }
 
 void
-opfunc_call_1 (OPCODE opdata)
+opfunc_call_1 (OPCODE opdata, struct __int_data *int_data)
 {
 #ifdef __HOST
   printf ("%d::op_call_1:idx:%d:%d\n",
-          __int_data.pos,
+          int_data->pos,
           opdata.data.call_1.name_lit_idx,
           opdata.data.call_1.arg1_lit_idx);
 #endif
 
-  __int_data.pos++;
+  int_data->pos++;
 }
 
 void
-opfunc_jmp (OPCODE opdata)
+opfunc_jmp (OPCODE opdata, struct __int_data *int_data)
 {
 #ifdef __HOST
   printf ("%d::op_jmp:idx:%d\n",
-          __int_data.pos,
+          int_data->pos,
           opdata.data.jmp.opcode_idx);
 #endif
 
-  __int_data.pos = opdata.data.jmp.opcode_idx;
+  int_data->pos = opdata.data.jmp.opcode_idx;
 }
 
 OPCODE
diff --git a/src/libcoreint/opcodes.h b/src/libcoreint/opcodes.h
index a48ba9e26..fd027e7c8 100644
--- a/src/libcoreint/opcodes.h
+++ b/src/libcoreint/opcodes.h
@@ -23,10 +23,11 @@
 #include "globals.h"
 
 #define OPCODE struct __opcode
+struct __int_data;
 
 #define OP_STRUCT_FIELD(name) struct __op_##name name;
 #define OP_ENUM_FIELD(name) name ,
-#define OP_FUNC_DECL(name) void opfunc_##name  (OPCODE);
+#define OP_FUNC_DECL(name) void opfunc_##name  (OPCODE, struct __int_data *);
 
 /** A single bytecode instruction is 32bit wide and has an 8bit opcode field
  and several operand of 8 of 16 bit.*/
@@ -35,7 +36,7 @@
 #define T_IDX uint8_t /** index values */
 
 OPCODE;
-typedef void (*opfunc)(OPCODE);
+typedef void (*opfunc)(OPCODE, struct __int_data *);
 
 #define OP_LOOPS(op)                    \
     op(loop_inf)                        \
@@ -57,7 +58,8 @@ typedef void (*opfunc)(OPCODE);
     op(varg_2_end)                      \
     op(varg_3)                          \
     op(varg_3_end)                      \
-    op(retval)
+    op(retval)\
+    op(ret)
 
 #define OP_ASSIGNMENTS(op)              \
     op(assignment)                      \
@@ -147,7 +149,7 @@ OPCODE
 }
 __packed;
 
-void save_op_data (OPCODE);
+void save_op_data (int, OPCODE);
 
 #endif	/* OPCODES_H */