@ -384,295 +384,283 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
| _ ->
false
let exec_instr ( astate : Domain . astate ) ( { ProcData . extras ; tenv ; pdesc ; } as proc_data ) _ instr =
let add_reads exps loc accesses locks attribute_map proc_data =
List . fold
~ f : ( fun acc exp -> add_access exp loc Read acc locks attribute_map proc_data )
exps
~ init : accesses
let exec_instr
( astate : Domain . astate )
( { ProcData . extras ; tenv ; pdesc ; } as proc_data )
_
( instr : HilInstr . t ) =
let open Domain in
let add_reads exps loc accesses locks attribute_map proc_data =
List . fold
~ f : ( fun acc exp -> add_access exp loc Read acc locks attribute_map proc_data )
exps
~ init : accesses in
let exec_instr_ = function
| HilInstr . Call ( Some ret_base , Direct procname , actuals , _ , loc )
when acquires_ownership procname tenv ->
let accesses =
add_reads actuals loc astate . accesses astate . locks astate . attribute_map proc_data in
let attribute_map =
AttributeMapDomain . add_attribute
( ret_base , [] ) Attribute . unconditionally_owned astate . attribute_map in
{ astate with accesses ; attribute_map ; }
| HilInstr . Call ( ret_opt , Direct callee_pname , actuals , call_flags , loc ) ->
let accesses =
add_reads actuals loc astate . accesses astate . locks astate . attribute_map proc_data in
let astate = { astate with accesses ; } in
let astate_callee =
(* assuming that modeled procedures do not have useful summaries *)
if is_thread_utils_method " assertMainThread " callee_pname
then
{ astate with threads = true ; }
else
match get_lock_model callee_pname with
| Lock ->
{ astate with locks = true ; }
| Unlock ->
{ astate with locks = false ; }
| LockedIfTrue ->
begin
match ret_opt with
| Some ret_access_path ->
let attribute_map =
AttributeMapDomain . add_attribute
( ret_access_path , [] )
( Choice Choice . LockHeld )
astate . attribute_map in
{ astate with attribute_map ; }
| None ->
failwithf
" Procedure %a specified as returning boolean, but returns nothing "
Typ . Procname . pp callee_pname
end
| NoEffect ->
match get_summary pdesc callee_pname actuals loc tenv with
| Some ( callee_threads , callee_locks , callee_accesses , return_attributes ) ->
let update_caller_accesses pre callee_accesses caller_accesses =
let combined_accesses =
PathDomain . with_callsite callee_accesses ( CallSite . make callee_pname loc )
| > PathDomain . join ( AccessDomain . get_accesses pre caller_accesses ) in
AccessDomain . add pre combined_accesses caller_accesses in
let locks = callee_locks | | astate . locks in
let threads = callee_threads | | astate . threads in
let unprotected = is_unprotected locks pdesc in
(* add [ownership_accesses] to the [accesses_acc] with a protected pre if
[ exp ] is owned , and an appropriate unprotected pre otherwise * )
let add_ownership_access ownership_accesses actual_exp accesses_acc =
match actual_exp with
| HilExp . Constant _ ->
(* the actual is a constant, so it's owned in the caller. *)
accesses_acc
| HilExp . AccessPath actual_access_path ->
if is_owned actual_access_path astate . attribute_map
then
(* the actual passed to the current callee is owned. drop all the
conditional accesses for that actual , since they're all safe * )
accesses_acc
else
let pre =
if unprotected
then
let base = fst actual_access_path in
match FormalMap . get_formal_index base extras with
| Some formal_index ->
(* the actual passed to the current callee is rooted in a
formal * )
AccessPrecondition . Unprotected ( Some formal_index )
| None ->
match
AttributeMapDomain . get_conditional_ownership_index
actual_access_path
astate . attribute_map
with
| Some formal_index ->
(* access path conditionally owned if [formal_index] is
owned * )
AccessPrecondition . Unprotected ( Some formal_index )
| None ->
(* access path not rooted in a formal and not
conditionally owned * )
AccessPrecondition . unprotected
else
(* access protected by held lock *)
AccessPrecondition . Protected in
update_caller_accesses pre ownership_accesses accesses_acc
| _ ->
(* couldn't find access path, don't know if it's owned *)
update_caller_accesses
AccessPrecondition . unprotected ownership_accesses accesses_acc in
let accesses =
let update_accesses pre callee_accesses accesses_acc = match pre with
| AccessPrecondition . Protected ->
update_caller_accesses pre callee_accesses accesses_acc
| AccessPrecondition . Unprotected None ->
let pre' =
if unprotected
then pre
else AccessPrecondition . Protected in
update_caller_accesses pre' callee_accesses accesses_acc
| AccessPrecondition . Unprotected ( Some index ) ->
add_ownership_access
callee_accesses ( List . nth_exn actuals index ) accesses_acc in
AccessDomain . fold update_accesses callee_accesses astate . accesses in
match instr with
| Call ( Some ret_base , Direct procname , actuals , _ , loc )
when acquires_ownership procname tenv ->
let accesses =
add_reads actuals loc astate . accesses astate . locks astate . attribute_map proc_data in
let attribute_map =
AttributeMapDomain . add_attribute
( ret_base , [] ) Attribute . unconditionally_owned astate . attribute_map in
{ astate with accesses ; attribute_map ; }
| Call ( ret_opt , Direct callee_pname , actuals , call_flags , loc ) ->
let accesses =
add_reads actuals loc astate . accesses astate . locks astate . attribute_map proc_data in
let astate = { astate with accesses ; } in
let astate_callee =
(* assuming that modeled procedures do not have useful summaries *)
if is_thread_utils_method " assertMainThread " callee_pname
then
{ astate with threads = true ; }
else
match get_lock_model callee_pname with
| Lock ->
{ astate with locks = true ; }
| Unlock ->
{ astate with locks = false ; }
| LockedIfTrue ->
begin
match ret_opt with
| Some ret_access_path ->
let attribute_map =
propagate_return_attributes
ret_opt
return_attributes
actuals
astate . attribute_map
extras in
{ astate with locks ; threads ; accesses ; attribute_map ; }
AttributeMapDomain . add_attribute
( ret_access_path , [] )
( Choice Choice . LockHeld )
astate . attribute_map in
{ astate with attribute_map ; }
| None ->
let should_assume_returns_ownership ( call_flags : CallFlags . t ) actuals =
(* assume non-interface methods with no summary and no parameters return
ownership * )
not ( call_flags . cf_interface ) && List . is_empty actuals in
if is_box callee_pname
then
match ret_opt , actuals with
| Some ret , HilExp . AccessPath actual_ap :: _
when AttributeMapDomain . has_attribute
actual_ap Functional astate . attribute_map ->
(* TODO: check for constants, which are functional? *)
let attribute_map =
AttributeMapDomain . add_attribute
( ret , [] )
Functional
astate . attribute_map in
{ astate with attribute_map ; }
| _ ->
astate
else if should_assume_returns_ownership call_flags actuals
then
match ret_opt with
| Some ret ->
let attribute_map =
AttributeMapDomain . add_attribute
( ret , [] )
Attribute . unconditionally_owned
astate . attribute_map in
{ astate with attribute_map ; }
| None ->
astate
else
astate in
begin
match ret_opt with
| Some ( _ , { Typ . desc = Typ . Tint ILong | Tfloat FDouble } ) ->
(* writes to longs and doubles are not guaranteed to be atomic in Java, so don't
bother tracking whether a returned long or float value is functional * )
astate_callee
| Some ret ->
let add_if_annotated predicate attribute attribute_map =
if PatternMatch . override_exists predicate tenv callee_pname
then
AttributeMapDomain . add_attribute ( ret , [] ) attribute attribute_map
else
attribute_map in
let attribute_map =
add_if_annotated is_functional Functional astate_callee . attribute_map
| > add_if_annotated
( has_return_annot Annotations . ia_is_returns_ownership )
Domain . Attribute . unconditionally_owned in
{ astate_callee with attribute_map ; }
| _ ->
astate_callee
end
failwithf
" Procedure %a specified as returning boolean, but returns nothing "
Typ . Procname . pp callee_pname
end
| NoEffect ->
match get_summary pdesc callee_pname actuals loc tenv with
| Some ( callee_threads , callee_locks , callee_accesses , return_attributes ) ->
let update_caller_accesses pre callee_accesses caller_accesses =
let combined_accesses =
PathDomain . with_callsite callee_accesses ( CallSite . make callee_pname loc )
| > PathDomain . join ( AccessDomain . get_accesses pre caller_accesses ) in
AccessDomain . add pre combined_accesses caller_accesses in
let locks = callee_locks | | astate . locks in
let threads = callee_threads | | astate . threads in
let unprotected = is_unprotected locks pdesc in
(* add [ownership_accesses] to the [accesses_acc] with a protected pre if
[ exp ] is owned , and an appropriate unprotected pre otherwise * )
let add_ownership_access ownership_accesses actual_exp accesses_acc =
match actual_exp with
| HilExp . Constant _ ->
(* the actual is a constant, so it's owned in the caller. *)
accesses_acc
| HilExp . AccessPath actual_access_path ->
if is_owned actual_access_path astate . attribute_map
then
(* the actual passed to the current callee is owned. drop all the
conditional accesses for that actual , since they're all safe * )
accesses_acc
else
let pre =
if unprotected
then
let base = fst actual_access_path in
match FormalMap . get_formal_index base extras with
| Some formal_index ->
(* the actual passed to the current callee is rooted in a
formal * )
AccessPrecondition . Unprotected ( Some formal_index )
| None ->
match
AttributeMapDomain . get_conditional_ownership_index
actual_access_path
astate . attribute_map
with
| Some formal_index ->
(* access path conditionally owned if [formal_index] is
owned * )
AccessPrecondition . Unprotected ( Some formal_index )
| None ->
(* access path not rooted in a formal and not
conditionally owned * )
AccessPrecondition . unprotected
else
(* access protected by held lock *)
AccessPrecondition . Protected in
update_caller_accesses pre ownership_accesses accesses_acc
| _ ->
(* couldn't find access path, don't know if it's owned *)
update_caller_accesses
AccessPrecondition . unprotected ownership_accesses accesses_acc in
let accesses =
let update_accesses pre callee_accesses accesses_acc = match pre with
| AccessPrecondition . Protected ->
update_caller_accesses pre callee_accesses accesses_acc
| AccessPrecondition . Unprotected None ->
let pre' =
if unprotected
then pre
else AccessPrecondition . Protected in
update_caller_accesses pre' callee_accesses accesses_acc
| AccessPrecondition . Unprotected ( Some index ) ->
add_ownership_access
callee_accesses ( List . nth_exn actuals index ) accesses_acc in
AccessDomain . fold update_accesses callee_accesses astate . accesses in
let attribute_map =
propagate_return_attributes
ret_opt
return_attributes
actuals
astate . attribute_map
extras in
{ locks ; threads ; accesses ; attribute_map ; }
| None ->
let should_assume_returns_ownership ( call_flags : CallFlags . t ) actuals =
(* assume non-interface methods with no summary and no parameters return
ownership * )
not ( call_flags . cf_interface ) && List . is_empty actuals in
if is_box callee_pname
then
match ret_opt , actuals with
| Some ret , HilExp . AccessPath actual_ap :: _
when AttributeMapDomain . has_attribute
actual_ap Functional astate . attribute_map ->
(* TODO: check for constants, which are functional? *)
let attribute_map =
AttributeMapDomain . add_attribute
( ret , [] )
Functional
astate . attribute_map in
{ astate with attribute_map ; }
| _ ->
astate
else if should_assume_returns_ownership call_flags actuals
then
match ret_opt with
| Some ret ->
let attribute_map =
AttributeMapDomain . add_attribute
( ret , [] )
Attribute . unconditionally_owned
astate . attribute_map in
{ astate with attribute_map ; }
| None ->
astate
else
astate in
begin
match ret_opt with
| Some ( _ , { Typ . desc = Typ . Tint ILong | Tfloat FDouble } ) ->
(* writes to longs and doubles are not guaranteed to be atomic in Java, so don't
bother tracking whether a returned long or float value is functional * )
astate_callee
| Some ret ->
let add_if_annotated predicate attribute attribute_map =
if PatternMatch . override_exists predicate tenv callee_pname
then
AttributeMapDomain . add_attribute ( ret , [] ) attribute attribute_map
else
attribute_map in
let attribute_map =
add_if_annotated is_functional Functional astate_callee . attribute_map
| > add_if_annotated
( has_return_annot Annotations . ia_is_returns_ownership )
Domain . Attribute . unconditionally_owned in
{ astate_callee with attribute_map ; }
| _ ->
astate_callee
end
| HilInstr . Write ( lhs_access_path , rhs_exp , loc ) ->
let rhs_accesses =
| Write ( lhs_access_path , rhs_exp , loc ) ->
let rhs_accesses =
add_access
rhs_exp loc Read astate . accesses astate . locks astate . attribute_map proc_data in
let rhs_access_paths = HilExp . get_access_paths rhs_exp in
let is_functional =
not ( List . is_empty rhs_access_paths ) &&
List . for_all
~ f : ( fun access_path ->
AttributeMapDomain . has_attribute access_path Functional astate . attribute_map )
rhs_access_paths in
let accesses =
if is_functional
then
(* we want to forget about writes to @Functional fields altogether, otherwise we'll
report spurious read / write races * )
rhs_accesses
else
add_access
rhs_exp loc Read astate . accesses astate . locks astate . attribute_map proc_data in
let rhs_access_paths = HilExp . get_access_paths rhs_exp in
let is_functional =
not ( List . is_empty rhs_access_paths ) &&
List . for_all
~ f : ( fun access_path ->
AttributeMapDomain . has_attribute access_path Functional astate . attribute_map )
rhs_access_paths in
let accesses =
if is_functional
then
(* we want to forget about writes to @Functional fields altogether, otherwise we'll
report spurious read / write races * )
( AccessPath lhs_access_path )
loc
Write
rhs_accesses
else
add_access
( AccessPath lhs_access_path )
loc
Write
rhs_accesses
astate . locks
astate . attribute_map
proc_data in
let attribute_map =
propagate_attributes
lhs_access_path ( HilExp . get_access_paths rhs_exp ) astate . attribute_map extras in
{ astate with accesses ; attribute_map ; }
| HilInstr . Assume ( assume_exp , _ , _ , loc ) ->
let rec eval_binop op var e1 e2 =
match eval_bexp var e1 , eval_bexp var e2 with
| Some b1 , Some b2 -> Some ( op b1 b2 )
| _ -> None
(* return Some bool_value if the given boolean expression evaluates to bool_value when
[ var ] is set to true . return None if it has free variables that stop us from
evaluating it * )
and eval_bexp var = function
| HilExp . AccessPath ap when AccessPath . Raw . equal ap var ->
Some true
| HilExp . Constant c ->
Some ( not ( Const . iszero_int_float c ) )
| HilExp . UnaryOperator ( Unop . LNot , e , _ ) ->
let b_opt = eval_bexp var e in
Option . map ~ f : not b_opt
| HilExp . BinaryOperator ( Binop . LAnd , e1 , e2 ) ->
eval_binop ( && ) var e1 e2
| HilExp . BinaryOperator ( Binop . LOr , e1 , e2 ) ->
eval_binop ( | | ) var e1 e2
| HilExp . BinaryOperator ( Binop . Eq , e1 , e2 ) ->
eval_binop Bool . equal var e1 e2
| HilExp . BinaryOperator ( Binop . Ne , e1 , e2 ) ->
eval_binop ( < > ) var e1 e2
| _ ->
(* non-boolean expression; can't evaluate it *)
None in
let add_choice bool_value acc = function
| Choice . LockHeld ->
let locks = bool_value in
{ acc with locks ; }
| Choice . OnMainThread ->
let threads = bool_value in
{ acc with threads ; } in
let accesses =
add_access
assume_exp loc Read astate . accesses astate . locks astate . attribute_map proc_data in
let astate' =
match HilExp . get_access_paths assume_exp with
| [ access_path ] ->
let choices = AttributeMapDomain . get_choices access_path astate . attribute_map in
begin
match eval_bexp access_path assume_exp with
| Some bool_value ->
(* prune ( prune_exp ) can only evaluate to true if the choice is [bool_value].
add the constraint that the the choice must be [ bool_value ] to the state * )
List . fold ~ f : ( add_choice bool_value ) ~ init : astate choices
| None ->
astate
end
| _ ->
astate in
{ astate' with accesses ; }
| ( HilInstr . Call ( _ , Indirect _ , _ , _ , _ ) as hil_instr ) ->
failwithf " Unexpected indirect call instruction %a " HilInstr . pp hil_instr in
let f_resolve_id id =
try Some ( IdAccessPathMapDomain . find id astate . id_map )
with Not_found -> None in
match HilInstr . of_sil ~ f_resolve_id instr with
| Bind ( id , access_path ) ->
let id_map = IdAccessPathMapDomain . add id access_path astate . id_map in
{ astate with id_map ; }
| Unbind ids ->
let id_map =
List . fold
~ f : ( fun acc id -> IdAccessPathMapDomain . remove id acc ) ~ init : astate . id_map ids in
{ astate with id_map ; }
| Instr hil_instr ->
exec_instr_ hil_instr
| Ignore ->
astate
astate . locks
astate . attribute_map
proc_data in
let attribute_map =
propagate_attributes
lhs_access_path ( HilExp . get_access_paths rhs_exp ) astate . attribute_map extras in
{ astate with accesses ; attribute_map ; }
| Assume ( assume_exp , _ , _ , loc ) ->
let rec eval_binop op var e1 e2 =
match eval_bexp var e1 , eval_bexp var e2 with
| Some b1 , Some b2 -> Some ( op b1 b2 )
| _ -> None
(* return Some bool_value if the given boolean expression evaluates to bool_value when
[ var ] is set to true . return None if it has free variables that stop us from
evaluating it * )
and eval_bexp var = function
| HilExp . AccessPath ap when AccessPath . Raw . equal ap var ->
Some true
| HilExp . Constant c ->
Some ( not ( Const . iszero_int_float c ) )
| HilExp . UnaryOperator ( Unop . LNot , e , _ ) ->
let b_opt = eval_bexp var e in
Option . map ~ f : not b_opt
| HilExp . BinaryOperator ( Binop . LAnd , e1 , e2 ) ->
eval_binop ( && ) var e1 e2
| HilExp . BinaryOperator ( Binop . LOr , e1 , e2 ) ->
eval_binop ( | | ) var e1 e2
| HilExp . BinaryOperator ( Binop . Eq , e1 , e2 ) ->
eval_binop Bool . equal var e1 e2
| HilExp . BinaryOperator ( Binop . Ne , e1 , e2 ) ->
eval_binop ( < > ) var e1 e2
| _ ->
(* non-boolean expression; can't evaluate it *)
None in
let add_choice bool_value acc = function
| Choice . LockHeld ->
let locks = bool_value in
{ acc with locks ; }
| Choice . OnMainThread ->
let threads = bool_value in
{ acc with threads ; } in
let accesses =
add_access
assume_exp loc Read astate . accesses astate . locks astate . attribute_map proc_data in
let astate' =
match HilExp . get_access_paths assume_exp with
| [ access_path ] ->
let choices = AttributeMapDomain . get_choices access_path astate . attribute_map in
begin
match eval_bexp access_path assume_exp with
| Some bool_value ->
(* prune ( prune_exp ) can only evaluate to true if the choice is [bool_value].
add the constraint that the the choice must be [ bool_value ] to the state * )
List . fold ~ f : ( add_choice bool_value ) ~ init : astate choices
| None ->
astate
end
| _ ->
astate in
{ astate' with accesses ; }
| Call ( _ , Indirect _ , _ , _ , _ ) ->
failwithf " Unexpected indirect call instruction %a " HilInstr . pp instr
end
module Analyzer = AbstractInterpreter . Make ( ProcCfg . Normal ) ( TransferFunctions )
module Analyzer = AbstractInterpreter . Make ( ProcCfg . Normal ) ( LowerHil . Make ( TransferFunctions ) )
module Interprocedural = AbstractInterpreter . Interprocedural ( Summary )
@ -810,12 +798,12 @@ let analyze_procedure callback =
~ f : add_owned_formal
owned_formals
~ init : ThreadSafetyDomain . empty . attribute_map in
{ ThreadSafetyDomain . empty with attribute_map ; threads ; }
{ ThreadSafetyDomain . empty with attribute_map ; threads ; } , IdAccessPathMapDomain . empty
else
{ ThreadSafetyDomain . empty with threads ; } in
{ ThreadSafetyDomain . empty with threads ; } , IdAccessPathMapDomain . empty in
match Analyzer . compute_post proc_data ~ initial with
| Some threads ; locks ; accesses ; attribute_map ; } ->
| Some ( { threads ; locks ; accesses ; attribute_map ; } , _ ) ->
let return_var_ap =
AccessPath . of_pvar
( Pvar . get_ret_pvar ( Procdesc . get_proc_name pdesc ) )
Sam Blackshear
8 years ago
committed by
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