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context_abstract_object.cpp
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1/*******************************************************************\
2
3 Module: analyses variable-sensitivity context_abstract_object
4
5 Author: Diffblue Ltd
6
7\*******************************************************************/
8
10
12
13#include <algorithm>
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54 abstract_environmentt &environment,
55 const namespacet &ns,
56 const std::stack<exprt> &stack,
57 const exprt &specifier,
58 const abstract_object_pointert &value,
59 bool merging_write) const
60{
62 environment, ns, stack, specifier, value, merging_write);
63
64 // Only perform an update if the write to the child has in fact changed it...
66 return shared_from_this();
67
68 return envelop(updated_child);
69}
70
84 const exprt &expr,
85 const std::vector<abstract_object_pointert> &operands,
86 const abstract_environmentt &environment,
87 const namespacet &ns) const
88{
89 PRECONDITION(expr.operands().size() == operands.size());
90 std::vector<abstract_object_pointert> child_operands;
91
92 std::transform(
93 operands.begin(),
94 operands.end(),
95 std::back_inserter(child_operands),
96 [](const abstract_object_pointert &op) {
97 PRECONDITION(op != nullptr);
98 auto p = std::dynamic_pointer_cast<const context_abstract_objectt>(op);
99 INVARIANT(p, "Operand shall be of type context_abstract_objectt");
100 return p->child_abstract_object;
101 });
102
103 auto result = child_abstract_object->expression_transform(
104 expr, child_operands, environment, ns);
105 return envelop(result);
106}
107
109 const locationt &location) const
110{
111 auto result = update_location_context_internal({location});
112
113 auto updated_child = child_abstract_object->write_location_context(location);
114 result->set_child(updated_child);
115
116 return result;
117}
118
121{
122 if(
123 std::dynamic_pointer_cast<const context_abstract_objectt>(object) !=
124 nullptr)
125 return object;
126
127 const auto &envelope =
128 std::dynamic_pointer_cast<context_abstract_objectt>(mutable_clone());
129 envelope->set_child(object);
130 return envelope;
131}
132
142 std::ostream &out,
143 const ai_baset &ai,
144 const namespacet &ns) const
145{
147}
148
158 const abstract_object_pointert &before) const
159{
160 // Default implementation, with no other information to go on
161 // falls back to relying on copy-on-write and pointer inequality
162 // to indicate if an abstract_objectt has been modified
163 auto before_context =
164 std::dynamic_pointer_cast<const context_abstract_objectt>(before);
165
166 return this->child_abstract_object != before_context->child_abstract_object;
167}
168
173
175{
176 return child_abstract_object->to_predicate(name);
177}
178
180 abstract_object_statisticst &statistics,
183 const namespacet &ns) const
184{
185 abstract_objectt::get_statistics(statistics, visited, env, ns);
186 if(visited.find(child_abstract_object) == visited.end())
187 {
188 child_abstract_object->get_statistics(statistics, visited, env, ns);
189 }
190 statistics.objects_memory_usage += memory_sizet::from_bytes(sizeof(*this));
191}
std::set< abstract_object_pointert > abstract_object_visitedt
sharing_ptrt< class abstract_objectt > abstract_object_pointert
Statistics gathering for the variable senstivity domain.
virtual internal_abstract_object_pointert mutable_clone() const
goto_programt::const_targett locationt
virtual void get_statistics(abstract_object_statisticst &statistics, abstract_object_visitedt &visited, const abstract_environmentt &env, const namespacet &ns) const
This is the basic interface of the abstract interpreter with default implementations of the core func...
Definition ai.h:117
virtual void output(const namespacet &ns, const irep_idt &function_id, const goto_programt &goto_program, std::ostream &out) const
Output the abstract states for a single function.
Definition ai.cpp:39
ait supplies three of the four components needed: an abstract interpreter (in this case handling func...
Definition ai.h:562
virtual context_abstract_object_ptrt update_location_context_internal(const locationst &locations) const =0
abstract_object_pointert write_location_context(const locationt &location) const override
Update the location context for an abstract object.
abstract_object_pointert envelop(abstract_object_pointert &child) const
void output(std::ostream &out, const class ai_baset &ai, const namespacet &ns) const override
Output a representation of the value of this abstract object.
bool has_been_modified(const abstract_object_pointert &before) const override
Determine whether 'this' abstract_object has been modified in comparison to a previous 'before' state...
abstract_object_pointert child_abstract_object
void set_child(const abstract_object_pointert &child)
void get_statistics(abstract_object_statisticst &statistics, abstract_object_visitedt &visited, const abstract_environmentt &env, const namespacet &ns) const override
abstract_object_pointert expression_transform(const exprt &expr, const std::vector< abstract_object_pointert > &operands, const abstract_environmentt &environment, const namespacet &ns) const override
Try to resolve an expression with the maximum level of precision available.
abstract_object_pointert write(abstract_environmentt &environment, const namespacet &ns, const std::stack< exprt > &stack, const exprt &specifier, const abstract_object_pointert &value, bool merging_write) const override
A helper function to evaluate writing to a component of an abstract object.
abstract_object_pointert get_child() const
abstract_object_pointert unwrap_context() const override
exprt to_predicate_internal(const exprt &name) const override
to_predicate implementation - derived classes will override
Base class for all expressions.
Definition expr.h:56
operandst & operands()
Definition expr.h:94
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
General implementation of a an abstract_objectt which can track side information in the form of a 'co...
#define PRECONDITION(CONDITION)
Definition invariant.h:463
memory_sizet objects_memory_usage
An underestimation of the memory usage of the abstract objects.