62 return (expr.
id() == ID_minus) &&
63 (expr.
operands()[0].type().id() == ID_pointer) &&
64 (expr.
operands()[1].type().id() == ID_pointer);
69 auto const &
id = expr.
id();
70 bool is_comparison =
id == ID_equal ||
id == ID_notequal ||
id == ID_lt ||
71 id == ID_le ||
id == ID_gt ||
id == ID_ge;
73 return is_comparison && (expr.
operands()[0].type().id() == ID_pointer) &&
74 (expr.
operands()[1].type().id() == ID_pointer);
79 return id == ID_member ||
id == ID_index ||
id == ID_dereference;
84 return id == ID_array ||
id == ID_struct ||
id == ID_constant ||
90 return expr.
id() == ID_side_effect && expr.
get(ID_statement) == ID_allocate;
102 const irep_idt simplified_id = simplified_expr.
id();
103 if(simplified_id == ID_symbol)
110 auto const operands =
eval_operands(simplified_expr, *
this, ns);
111 auto const &target = operands.front();
113 return target->expression_transform(simplified_expr, operands, *
this, ns);
121 typet(ID_dynamic_object),
122 exprt(ID_dynamic_object, simplified_expr.
type()),
127 if(!simplified_expr.
operands().empty())
142 if(symbol_entry.has_value())
143 return symbol_entry.value();
154 if(value->is_bottom())
156 bool bottom_at_start = this->
is_bottom();
158 return !bottom_at_start;
165 std::stack<exprt> stactions;
166 while(s.
id() != ID_symbol)
168 if(s.
id() == ID_index || s.
id() == ID_member || s.
id() == ID_dereference)
175 lhs_value =
eval(s, ns);
182 INVARIANT(s.
id() == ID_symbol,
"Have a symbol or a stack");
191 if(!stactions.empty())
194 final_value =
write(lhs_value, value, stactions, ns,
false);
201 if(s.
id() != ID_symbol)
203 throw std::runtime_error(
"invalid l-value");
209 const typet &lhs_type = ns.
follow(lhs_value->type());
210 const typet &rhs_type = ns.
follow(final_value->type());
214 lhs_type == rhs_type,
215 "Assignment types must match"
224 if(s.
id() == ID_symbol)
228 if(final_value != lhs_value)
240 std::stack<exprt> remaining_stack,
245 const exprt &next_expr = remaining_stack.top();
246 remaining_stack.pop();
248 const irep_idt &stack_head_id = next_expr.
id();
250 stack_head_id == ID_index || stack_head_id == ID_member ||
251 stack_head_id == ID_dereference,
252 "Write stack expressions must be index, member, or dereference");
254 return lhs->write(*
this, ns, remaining_stack, next_expr, rhs, merge_write);
265 auto assumption =
do_assume(simplified, ns);
267 if(assumption.id() != ID_nil)
271 assumption.type().id() == ID_bool,
"simplification preserves type");
273 if(assumption.is_false())
277 return !currently_bottom;
285 std::map<irep_idt, assume_function>{{ID_not,
assume_not},
302 auto expr_id = expr.
id();
307 return fn(*
this, expr, ns);
309 return eval(expr, ns)->to_constant();
320 type, top, bttm, empty_constant_expr, *
this, ns);
340 type, top, bttm, e, environment, ns);
366 bool modified =
false;
367 for(
const auto &entry : env.
map.get_delta_view(
map))
370 entry.get_other_map_value(), entry.m, merge_location, widen_mode);
372 modified |= merge_result.modified;
373 map.replace(entry.k, merge_result.object);
415 for(
const auto &entry :
map.get_view())
417 out << entry.first <<
" () -> ";
418 entry.second->output(out, ai, ns);
433 for(
const auto &entry :
map.get_view())
435 auto sym = entry.first;
436 auto val = entry.second;
437 auto pred = val->to_predicate(
symbol_exprt(sym, val->type()));
439 predicates.push_back(pred);
442 if(predicates.size() == 1)
443 return predicates.front();
451 for(
const auto &entry :
map.get_view())
453 if(entry.second ==
nullptr)
473 return eval_obj->expression_transform(e, operands, *
this, ns);
481std::vector<abstract_environmentt::map_keyt>
487 std::vector<abstract_environmentt::map_keyt> symbols_diff;
488 for(
const auto &entry : first.
map.get_view())
490 const auto &second_entry = second.
map.find(entry.first);
491 if(second_entry.has_value())
493 if(second_entry.value().get()->has_been_modified(entry.second))
496 symbols_diff.push_back(entry.first);
502 for(
const auto &entry : second.
map.get_view())
504 const auto &second_entry = first.
map.find(entry.first);
505 if(!second_entry.has_value())
508 symbols_diff.push_back(entry.first);
517 auto val = std::count_if(
520 [](
const symbol_tablet::const_iteratort::value_type &sym) {
521 return sym.second.is_lvalue && sym.second.is_static_lifetime;
532 for(
auto const &
object :
map.get_view())
534 if(visited.find(
object.second) == visited.end())
536 object.second->get_statistics(statistics, visited, *
this, ns);
547 std::vector<abstract_object_pointert> operands;
549 for(
const auto &op : expr.
operands())
550 operands.push_back(env.
eval(op, ns));
558 return std::dynamic_pointer_cast<const abstract_value_objectt>(
559 obj->unwrap_context());
568 std::map<irep_idt, irep_idt>{{ID_equal, ID_notequal},
569 {ID_notequal, ID_equal},
587 auto expr_id = expr.
id();
594 auto inverse_op = inverse_operation->second;
596 relation_expr.lhs(), inverse_op, relation_expr.rhs());
602 const exprt &destination,
607 std::dynamic_pointer_cast<const context_abstract_objectt>(previous);
608 if(context !=
nullptr)
609 obj = context->envelop(obj);
610 env.
assign(destination, obj, ns);
620 auto inverse_expression =
invert_expr(not_expr.op());
621 if(inverse_expression.is_not_nil())
622 return env.
do_assume(inverse_expression, ns);
624 auto result = env.
do_assume(not_expr.op(), ns);
635 for(
auto const &operand : and_expr.operands())
637 auto result = env.
do_assume(operand, ns);
638 if(result.is_false())
655 for(
auto const &operand : or_expr.operands())
680 return left ==
nullptr ||
right ==
nullptr ||
687 return left->is_top() ||
right->is_top();
698 auto lhs = relationship_expr.lhs();
699 auto rhs = relationship_expr.rhs();
700 auto left = env.
eval(lhs, ns);
701 auto right = env.
eval(rhs, ns);
703 if(left->is_top() && right->is_top())
706 return {lhs, rhs, left, right};
717 auto constrained = std::make_shared<interval_abstract_valuet>(
724 auto constrained = std::make_shared<interval_abstract_valuet>(
738 if(operands.are_bad())
741 if(operands.has_top())
744 auto meet = operands.left->meet(operands.right);
746 if(meet->is_bottom())
750 prune_assign(env, operands.left, operands.lhs, meet, ns);
752 prune_assign(env, operands.right, operands.rhs, meet, ns);
763 auto left = env.
eval(notequal_expr.lhs(), ns);
764 auto right = env.
eval(notequal_expr.rhs(), ns);
766 if(left->is_top() || right->is_top())
771 auto meet = left->meet(right);
773 if(meet->is_bottom())
790 operands.
left->type());
792 std::make_shared<interval_abstract_valuet>(pruned_expr, env, ns);
801 operands.
right->type());
803 std::make_shared<interval_abstract_valuet>(pruned_expr, env, ns);
816 if(operands.are_bad())
819 if(operands.has_top())
822 auto left_interval = operands.left_interval();
823 auto right_interval = operands.right_interval();
825 const auto &left_lower = left_interval.get_lower();
826 const auto &right_upper = right_interval.get_upper();
828 auto reduced_le_expr =
830 auto result = env.
eval(reduced_le_expr, ns)->to_constant();
836 left_interval.get_upper(), right_upper);
838 as_value(operands.left)->constrain(left_lower, pruned_upper);
839 prune_assign(env, operands.left, operands.lhs, constrained, ns);
844 left_lower, right_interval.get_lower());
846 as_value(operands.right)->constrain(pruned_lower, right_upper);
847 prune_assign(env, operands.right, operands.rhs, constrained, ns);
854 std::map<irep_idt, irep_idt>{{ID_ge, ID_le}, {ID_gt, ID_lt}};
864 auto symmetric_expr =
std::vector< abstract_object_pointert > eval_operands(const exprt &expr, const abstract_environmentt &env, const namespacet &ns)
static auto assume_functions
static bool is_value(const abstract_object_pointert &obj)
static exprt assume_not(abstract_environmentt &env, const exprt &expr, const namespacet &ns)
static auto inverse_operations
static exprt invert_expr(const exprt &expr)
static abstract_value_pointert as_value(const abstract_object_pointert &obj)
static bool is_object_creation(const irep_idt &id)
static auto symmetric_operations
static bool is_access_expr(const irep_idt &id)
left_and_right_valuest eval_operands_as_values(abstract_environmentt &env, const exprt &expr, const namespacet &ns)
static exprt assume_eq(abstract_environmentt &env, const exprt &expr, const namespacet &ns)
static exprt assume_noteq(abstract_environmentt &env, const exprt &expr, const namespacet &ns)
static std::size_t count_globals(const namespacet &ns)
static exprt assume_or(abstract_environmentt &env, const exprt &expr, const namespacet &ns)
exprt(* assume_function)(abstract_environmentt &, const exprt &, const namespacet &)
static exprt assume_less_than(abstract_environmentt &env, const exprt &expr, const namespacet &ns)
static exprt invert_result(const exprt &result)
exprt assume_less_than_unbounded(abstract_environmentt &env, const left_and_right_valuest &operands, const namespacet &ns)
static exprt assume_and(abstract_environmentt &env, const exprt &expr, const namespacet &ns)
bool is_ptr_comparison(const exprt &expr)
void prune_assign(abstract_environmentt &env, const abstract_object_pointert &previous, const exprt &destination, abstract_object_pointert obj, const namespacet &ns)
static bool is_dynamic_allocation(const exprt &expr)
exprt assume_eq_unbounded(abstract_environmentt &env, const left_and_right_valuest &operands, const namespacet &ns)
static exprt assume_greater_than(abstract_environmentt &env, const exprt &expr, const namespacet &ns)
bool is_ptr_diff(const exprt &expr)
An abstract version of a program environment.
bool is_ptr_comparison(const exprt &expr)
bool is_ptr_diff(const exprt &expr)
std::set< abstract_object_pointert > abstract_object_visitedt
sharing_ptrt< class abstract_objectt > abstract_object_pointert
Statistics gathering for the variable senstivity domain.
sharing_ptrt< const abstract_value_objectt > abstract_value_pointert
virtual bool assume(const exprt &expr, const namespacet &ns)
Reduces the domain based on a condition.
void output(std::ostream &out, const class ai_baset &ai, const namespacet &ns) const
Print out all the values in the abstract object map.
bool is_bottom() const
Gets whether the domain is bottom.
abstract_object_pointert resolve_symbol(const exprt &e, const namespacet &ns) const
exprt to_predicate() const
Gives a boolean condition that is true for all values represented by the environment.
void make_top()
Set the domain to top (i.e. everything)
virtual abstract_object_pointert eval(const exprt &expr, const namespacet &ns) const
These three are really the heart of the method.
void erase(const symbol_exprt &expr)
Delete a symbol from the map.
static std::vector< abstract_environmentt::map_keyt > modified_symbols(const abstract_environmentt &first, const abstract_environmentt &second)
For our implementation of variable sensitivity domains, we need to be able to efficiently find symbol...
bool verify() const
Check the structural invariants are maintained.
virtual void havoc(const std::string &havoc_string)
This should be used as a default case / everything else has failed The string is so that I can easily...
exprt do_assume(const exprt &e, const namespacet &ns)
const vsd_configt & configuration() const
Exposes the environment configuration.
variable_sensitivity_object_factory_ptrt object_factory
virtual abstract_object_pointert write(const abstract_object_pointert &lhs, const abstract_object_pointert &rhs, std::stack< exprt > remaining_stack, const namespacet &ns, bool merge_write)
Used within assign to do the actual dispatch.
abstract_object_statisticst gather_statistics(const namespacet &ns) const
virtual bool merge(const abstract_environmentt &env, const goto_programt::const_targett &merge_location, widen_modet widen_mode)
Computes the join between "this" and "b".
void make_bottom()
Set the domain to top (i.e. no possible states / unreachable)
bool is_top() const
Gets whether the domain is top.
virtual abstract_object_pointert abstract_object_factory(const typet &type, const namespacet &ns, bool top, bool bottom) const
Look at the configuration for the sensitivity and create an appropriate abstract_object.
virtual abstract_object_pointert eval_expression(const exprt &e, const namespacet &ns) const
virtual bool assign(const exprt &expr, const abstract_object_pointert &value, const namespacet &ns)
Assign a value to an expression.
sharing_mapt< map_keyt, abstract_object_pointert > map
static combine_result merge(const abstract_object_pointert &op1, const abstract_object_pointert &op2, const locationt &merge_location, const widen_modet &widen_mode)
This is the basic interface of the abstract interpreter with default implementations of the core func...
A base class for relations, i.e., binary predicates whose two operands have the same type.
Represents an interval of values.
static exprt get_max(const exprt &a, const exprt &b)
static exprt get_min(const exprt &a, const exprt &b)
const exprt & get_lower() const
const exprt & get_upper() const
dstringt has one field, an unsigned integer no which is an index into a static table of strings.
Base class for all expressions.
std::vector< exprt > operandst
bool is_true() const
Return whether the expression is a constant representing true.
bool is_boolean() const
Return whether the expression represents a Boolean.
typet & type()
Return the type of the expression.
The Boolean constant false.
instructionst::const_iterator const_targett
std::string pretty(unsigned indent=0, unsigned max_indent=0) const
const irep_idt & get(const irep_idt &name) const
const irep_idt & id() const
+∞ upper bound for intervals
-∞ upper bound for intervals
const typet & follow(const typet &) const
Resolve type symbol to the type it points to.
A namespacet is essentially one or two symbol tables bound together, to allow for symbol lookups in t...
const symbol_table_baset & get_symbol_table() const
Return first symbol table registered with the namespace.
Expression to hold a symbol (variable)
const irep_idt & get_identifier() const
The Boolean constant true.
The type of an expression, extends irept.
bool is_assignable(const exprt &expr)
Returns true iff the argument is one of the following:
Deprecated expression utility functions.
exprt simplify_expr(exprt src, const namespacet &ns)
bool sort_operands(exprt::operandst &operands)
sort operands of an expression according to ordering defined by operator<
#define CHECK_RETURN(CONDITION)
#define PRECONDITION(CONDITION)
#define INVARIANT(CONDITION, REASON)
This macro uses the wrapper function 'invariant_violated_string'.
const binary_relation_exprt & to_binary_relation_expr(const exprt &expr)
Cast an exprt to a binary_relation_exprt.
const and_exprt & to_and_expr(const exprt &expr)
Cast an exprt to a and_exprt.
const or_exprt & to_or_expr(const exprt &expr)
Cast an exprt to a or_exprt.
const binary_exprt & to_binary_expr(const exprt &expr)
Cast an exprt to a binary_exprt.
const not_exprt & to_not_expr(const exprt &expr)
Cast an exprt to an not_exprt.
const symbol_exprt & to_symbol_expr(const exprt &expr)
Cast an exprt to a symbol_exprt.
std::size_t number_of_globals
abstract_object_pointert right
constant_interval_exprt right_interval() const
constant_interval_exprt left_interval() const
abstract_object_pointert left
Tracks the user-supplied configuration for VSD and build the correct type of abstract object when nee...