pghs975uc
/
infer_clone
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

refactor pruning code in symExec.ml

Browse Source 
Summary: public
Refactor how propositions are created from prune nodes, especially for
inequalities.

Reviewed By: cristianoc

Differential Revision: D2700119

fb-gh-sync-id: 86a70a3
master
Jules Villard 9 years ago committed by facebook-github-bot-1
parent 5a4f5fa444
commit f7ecf30739
1 changed files with 44 additions and 48 deletions
Show Stats Download Patch File Download Diff File

92
infer/src/backend/symExec.ml
Unescape View File

@ -395,14 +395,44 @@ let prune_ne tenv positive e1 e2 prop =
let is_inconsistent =
if positive then Prover.check_equal prop e1 e2
else Prover.check_disequal prop e1 e2 in
if is_inconsistent then Propset.empty else
let new_prop =
if positive then Prop.conjoin_neq ~footprint: (!Config.footprint) e1 e2 prop
else Prop.conjoin_eq ~footprint: (!Config.footprint) e1 e2 prop
in if Prover.check_inconsistency new_prop then Propset.empty
if is_inconsistent then Propset.empty
else
let conjoin = if positive then Prop.conjoin_neq else Prop.conjoin_eq in
let new_prop = conjoin ~footprint: (!Config.footprint) e1 e2 prop in
if Prover.check_inconsistency new_prop then Propset.empty
else Propset.singleton new_prop
let rec prune_polarity tenv positive (condition : Sil.exp) (prop : Prop.normal Prop.t) = match condition with
(** Do pruning for conditional "if ([e1] CMP [e2])" if [positive] is
true and "if (!([e1] CMP [e2]))" if [positive] is false, where CMP
is "<" if [is_strict] is true and "<=" if [is_strict] is false.
*)
let prune_ineq ~is_strict positive prop e1 e2 =
if Sil.exp_equal e1 e2 then
if (positive && not is_strict) || (not positive && is_strict) then
Propset.singleton prop
else Propset.empty
else
(* build the pruning condition and its negation, as explained in
the comment above *)
(* build [e1] CMP [e2] *)
let cmp = if is_strict then Sil.Lt else Sil.Le in
let e1_cmp_e2 = Sil.BinOp (cmp, e1, e2) in
(* build !([e1] CMP [e2]) *)
let dual_cmp = if is_strict then Sil.Le else Sil.Lt in
let not_e1_cmp_e2 = Sil.BinOp (dual_cmp, e2, e1) in
(* take polarity into account *)
let (prune_cond, not_prune_cond) =
if positive then (e1_cmp_e2, not_e1_cmp_e2)
else (not_e1_cmp_e2, e1_cmp_e2) in
let is_inconsistent = Prover.check_atom prop (Prop.mk_inequality not_prune_cond) in
if is_inconsistent then Propset.empty
else
let footprint = !Config.footprint in
let prop_with_ineq = Prop.conjoin_eq ~footprint prune_cond Sil.exp_one prop in
Propset.singleton prop_with_ineq
let rec prune_polarity tenv positive condition prop =
match condition with
| Sil.Var _ | Sil.Lvar _ ->
prune_ne tenv positive condition Sil.exp_zero prop
| Sil.Const (Sil.Cint i) when Sil.Int.iszero i ->
@ -428,49 +458,15 @@ let rec prune_polarity tenv positive (condition : Sil.exp) (prop : Prop.normal P
| Sil.BinOp (Sil.Ne, e1, e2) ->
prune_ne tenv positive e1 e2 prop
| Sil.BinOp (Sil.Ge, e2, e1) | Sil.BinOp (Sil.Le, e1, e2) ->
(* e1<=e2 Case. Encode it as (e1<=e2)=1 *)
if Sil.exp_equal e1 e2 then
if positive then Propset.singleton prop else Propset.empty
else
let e2_lt_e1 = Sil.BinOp (Sil.Lt, e2, e1) in (* e2 < e1 *)
let e1_le_e2 = Sil.BinOp (Sil.Le, e1, e2) in (* e1 <= e2 *)
let is_inconsistent =
if positive then Prover.check_atom prop (Prop.mk_inequality e2_lt_e1) (* e2 < e1 *)
else Prover.check_atom prop (Prop.mk_inequality e1_le_e2) (* e1 <= e2 *) in
begin
if is_inconsistent then
Propset.empty
else if positive then
Propset.singleton
(Prop.conjoin_eq ~footprint: (!Config.footprint) e1_le_e2 Sil.exp_one prop)
else
Propset.singleton
(Prop.conjoin_eq ~footprint: (!Config.footprint) e2_lt_e1 Sil.exp_one prop)
end
prune_ineq ~is_strict:false positive prop e1 e2
| Sil.BinOp (Sil.Gt, e2, e1) | Sil.BinOp (Sil.Lt, e1, e2) ->
(* e1 < e2 Case. Encode it as (e1<e2)=1 *)
if Sil.exp_equal e1 e2 then
if positive then Propset.empty else Propset.singleton prop
else
let e1_lt_e2 = Sil.BinOp(Sil.Lt, e1, e2) in (* e1 < e2 *)
let e2_le_e1 = Sil.BinOp(Sil.Le, e2, e1) in (* e2 <= e1 *)
let is_inconsistent =
if positive then Prover.check_atom prop (Prop.mk_inequality e2_le_e1) (* e2 <= e1 *)
else Prover.check_atom prop (Prop.mk_inequality e1_lt_e2) (* e1 < e2 *) in
begin
if is_inconsistent then
Propset.empty
else if positive then
Propset.singleton
(Prop.conjoin_eq ~footprint: (!Config.footprint) e1_lt_e2 Sil.exp_one prop)
else
Propset.singleton
(Prop.conjoin_eq ~footprint: (!Config.footprint) e2_le_e1 Sil.exp_one prop)
end
prune_ineq ~is_strict:true positive prop e1 e2
| Sil.BinOp (Sil.LAnd, condition1, condition2) ->
(if positive then prune_polarity_inter else prune_polarity_union) tenv positive condition1 condition2 prop
let pruner = if positive then prune_polarity_inter else prune_polarity_union in
pruner tenv positive condition1 condition2 prop
| Sil.BinOp (Sil.LOr, condition1, condition2) ->
(if positive then prune_polarity_union else prune_polarity_inter) tenv positive condition1 condition2 prop
let pruner = if positive then prune_polarity_union else prune_polarity_inter in
pruner tenv positive condition1 condition2 prop
| Sil.BinOp _ | Sil.Lfield _ | Sil.Lindex _ ->
prune_ne tenv positive condition Sil.exp_zero prop
@ -1620,8 +1616,8 @@ module ModelBuiltins = struct
let prop''= Prop.normalize prop'' in
prop''
| None -> prop in
let sil_is_null = Sil.BinOp (Sil.Eq, n_lexp, (Sil.exp_zero)) in
let sil_is_nonnull = Sil.UnOp(Sil.LNot, sil_is_null, None) in
let sil_is_null = Sil.BinOp (Sil.Eq, n_lexp, Sil.exp_zero) in
let sil_is_nonnull = Sil.UnOp (Sil.LNot, sil_is_null, None) in
let null_case = Propset.to_proplist (prune_prop tenv sil_is_null prop) in
let non_null_case = Propset.to_proplist (prune_prop tenv sil_is_nonnull prop_type) in
if ((IList.length non_null_case) > 0) && (!Config.footprint) then

Write Preview
Loading…
Cancel
Save