Remark eval_builtin_args_trivial:
forall (ge: RTL.genv) (rs: regset) sp m rl,
eval_builtin_args ge (fun r => rs#r) sp m (List.map (@BA reg) rl) rs##rl.

Lemma transl_expr_Ebuiltin_correct:
forall le ef al vl v,
eval_exprlist ge sp e m le al vl ->
transl_exprlist_prop le al vl ->
external_call ef ge vl m E0 v m ->
transl_expr_prop le (Ebuiltin ef al) v.