Ltac go_lower0 :=
intros ?rho;
try (simple apply grab_tc_environ; intro);
repeat (progress unfold_for_go_lower; simpl).
Ltac old_go_lower :=
go_lower0;
autorewrite with go_lower;
try findvars;
simpl;
autorewrite with go_lower;
try match goal with H: tc_environ _ ?rho |- _ => clear H rho end.
Hint Rewrite eval_id_same : go_lower.
Hint Rewrite eval_id_other using solve [clear; intro Hx; inversion Hx] : go_lower.
(*Hint Rewrite Vint_inj' : go_lower.*)
(*** New go_lower stuff ****)

Lemma lower_one_lvar:
forall t rho Delta P i v Q R S,
(headptr v -> lvar_denote i t v rho ->
(local (tc_environ Delta) && PROPx P (LOCALx Q (SEPx R))) rho |-- S) ->
(local (tc_environ Delta) && PROPx P (LOCALx (lvar i t v :: Q) (SEPx R))) rho |-- S.