Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.Record fsim_properties_ext: Type :=
  {
    Extindex: Type;
    Extorder: Extindex -> Extindex -> Prop;
    Extmatch_states: Extindex -> state L1 -> state L2 -> Prop;  
    Extfsim_order_wf: well_founded Extorder;
    Extfsim_match_meminj: forall i s1 s2, Extmatch_states i s1 s2 ->  Mem.extends (get_mem1 s1) (get_mem2 s2);
    Extfsim_match_start_stacks:
      forall s1 f arg m0, start_stack L1 m0 s1 f arg  ->
                     exists i s2, start_stack L2 m0 s2 f arg /\ Extmatch_states i s1 s2;
    Extfsim_match_initial_states:
      forall s1, initial_state L1 s1 -> 
               exists i s2, initial_state L2 s2 /\ Extmatch_states i s1 s2;
    Extfsim_match_final_states:
      forall i s1 s2 r ,
      Extmatch_states i s1 s2 -> final_state L1 s1 r -> (final_state L2 s2 r);
    Extfsim_simulation:
      forall s1 t s1', Step L1 s1 t s1' ->
      forall i s2, Extmatch_states i s1 s2 ->
      exists i', exists s2',
         (Plus L2 s2 t s2' \/ (Star L2 s2 t s2' /\ Extorder i' i))
         /\ Extmatch_states i' s1' s2';
    Extfsim_public_preserved:
      forall id, Senv.public_symbol (symbolenv L2) id = Senv.public_symbol (symbolenv L1) id
  }.

Lemma Extsimulation_plus: forall (SIM: fsim_properties_ext), forall s1 t s1', Plus L1 s1 t s1' -> forall i s2, Extmatch_states SIM i s1 s2 -> (exists i', exists s2', Plus L2 s2 t s2' /\ Extmatch_states SIM i' s1' s2') \/ (exists i', clos_trans _ (Extorder SIM) i' i /\ t = E0 /\ Extmatch_states SIM i' s1' s2).