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constant_abstract_value.cpp
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1/*******************************************************************\
2
3 Module: analyses variable-sensitivity
4
5 Author: Thomas Kiley, thomas.kiley@diffblue.com
6
7\*******************************************************************/
8
10
11#include <util/interval.h>
12#include <util/std_expr.h>
13
16
19
33
36{
37 return std::make_unique<constant_index_ranget>(val);
38}
39
44
46 const typet &t,
47 bool tp,
48 bool bttm)
49 : abstract_value_objectt(t, tp, bttm), value()
50{
51}
52
54 const exprt &e,
55 const abstract_environmentt &environment,
56 const namespacet &ns)
57 : abstract_value_objectt(e.type(), false, false), value(e)
58{
59}
60
70
76
78{
79 if(!is_top() && !is_bottom())
80 {
81 return this->value;
82 }
83 else
84 {
86 }
87}
88
93
95 std::ostream &out,
96 const ai_baset &ai,
97 const namespacet &ns) const
98{
99 if(!is_top() && !is_bottom())
100 {
102 }
103 else
104 {
106 }
107}
108
110 const abstract_value_pointert &other,
111 const widen_modet &widen_mode) const
112{
113 auto other_expr = other->to_constant();
114 if(is_bottom() && other_expr.is_constant())
115 return std::make_shared<constant_abstract_valuet>(other_expr);
116
117 if(value == other_expr) // Can we actually merge these value
118 return shared_from_this();
119
120 return abstract_objectt::merge(other, widen_mode);
121}
122
124 const abstract_value_pointert &other) const
125{
127 auto other_interval = other->to_interval();
128
129 if(other_interval.contains(value_as_interval)) // Do they actually meet
130 return shared_from_this();
131
132 return abstract_objectt::meet(other);
133}
134
136 const exprt &lower,
137 const exprt &upper) const
138{
139 return as_value(mutable_clone());
140}
141
143{
144 return equal_exprt(name, value);
145}
146
148 abstract_object_statisticst &statistics,
151 const namespacet &ns) const
152{
153 abstract_objectt::get_statistics(statistics, visited, env, ns);
154 ++statistics.number_of_constants;
155 statistics.objects_memory_usage += memory_sizet::from_bytes(sizeof(*this));
156}
std::set< abstract_object_pointert > abstract_object_visitedt
sharing_ptrt< class abstract_objectt > abstract_object_pointert
Statistics gathering for the variable senstivity domain.
index_range_implementation_ptrt make_indeterminate_index_range()
value_range_implementation_ptrt make_single_value_range(const abstract_object_pointert &value)
std::unique_ptr< index_range_implementationt > index_range_implementation_ptrt
std::unique_ptr< value_range_implementationt > value_range_implementation_ptrt
virtual exprt to_constant() const
Converts to a constant expression if possible.
virtual bool is_top() const
Find out if the abstract object is top.
virtual bool is_bottom() const
Find out if the abstract object is bottom.
static combine_result merge(const abstract_object_pointert &op1, const abstract_object_pointert &op2, const locationt &merge_location, const widen_modet &widen_mode)
virtual void output(std::ostream &out, const class ai_baset &ai, const namespacet &ns) const
Print the value of the abstract object.
static combine_result meet(const abstract_object_pointert &op1, const abstract_object_pointert &op2)
Interface method for the meet operation.
virtual void get_statistics(abstract_object_statisticst &statistics, abstract_object_visitedt &visited, const abstract_environmentt &env, const namespacet &ns) const
sharing_ptrt< const abstract_value_objectt > as_value(const abstract_object_pointert &obj) const
sharing_ptrt< const abstract_value_objectt > abstract_value_pointert
This is the basic interface of the abstract interpreter with default implementations of the core func...
Definition ai.h:117
ait supplies three of the four components needed: an abstract interpreter (in this case handling func...
Definition ai.h:562
void output(std::ostream &out, const class ai_baset &ai, const class namespacet &ns) const override
void get_statistics(abstract_object_statisticst &statistics, abstract_object_visitedt &visited, const abstract_environmentt &env, const namespacet &ns) const override
value_range_implementation_ptrt value_range_implementation() const override
constant_interval_exprt to_interval() const override
index_range_implementation_ptrt index_range_implementation(const namespacet &ns) const override
abstract_value_pointert constrain(const exprt &lower, const exprt &upper) const override
internal_abstract_object_pointert mutable_clone() const override
exprt to_constant() const override
Converts to a constant expression if possible.
exprt to_predicate_internal(const exprt &name) const override
to_predicate implementation - derived classes will override
abstract_object_pointert merge_with_value(const abstract_value_pointert &other, const widen_modet &widen_mode) const override
Merges another abstract value into this one.
abstract_object_pointert meet_with_value(const abstract_value_pointert &other) const override
index_range_implementation_ptrt reset() const override
constant_index_ranget(const exprt &val)
Represents an interval of values.
Definition interval.h:52
Equality.
Definition std_expr.h:1366
Base class for all expressions.
Definition expr.h:56
static memory_sizet from_bytes(std::size_t bytes)
A namespacet is essentially one or two symbol tables bound together, to allow for symbol lookups in t...
Definition namespace.h:91
The type of an expression, extends irept.
Definition type.h:29
static index_range_implementation_ptrt make_constant_index_range(const exprt &val)
An abstraction of a single value that just stores a constant.
std::string from_expr(const namespacet &ns, const irep_idt &identifier, const exprt &expr)
API to expression classes.
const constant_exprt & to_constant_expr(const exprt &expr)
Cast an exprt to a constant_exprt.
Definition std_expr.h:3172
memory_sizet objects_memory_usage
An underestimation of the memory usage of the abstract objects.