Arguments reach_in_exported_tgt {b m args} j _.

Lemma safe_match_target_step cd j c m d tm z tr :
(forall n, safeN tr_source geS n (z,tr,c) m) ->
match_state cd j c m d tm ->
~TraceSemantics.yielded target d ->
exists c' m' d' tm' n tn,
corestepN source geS n c m c' m'
/\ corestepN target geT (S tn) d tm d' tm'
/\ exists cd' j', match_state cd' j' c' m' d' tm'.