cprover
value_set_dereference.h
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1 /*******************************************************************\
2 
3 Module: Pointer Dereferencing
4 
5 Author: Daniel Kroening, kroening@kroening.com
6 
7 \*******************************************************************/
8 
11 
12 #ifndef CPROVER_POINTER_ANALYSIS_VALUE_SET_DEREFERENCE_H
13 #define CPROVER_POINTER_ANALYSIS_VALUE_SET_DEREFERENCE_H
14 
15 #include <util/std_expr.h>
16 
18 class messaget;
19 class symbol_tablet;
20 
23 {
24 public:
32  // given dereference may follow a null pointer
35  const namespacet &_ns,
36  symbol_tablet &_new_symbol_table,
37  dereference_callbackt &_dereference_callback,
38  const irep_idt _language_mode,
39  bool _exclude_null_derefs,
40  const messaget &_log)
41  : ns(_ns),
42  new_symbol_table(_new_symbol_table),
43  dereference_callback(_dereference_callback),
44  language_mode(_language_mode),
45  exclude_null_derefs(_exclude_null_derefs),
46  log(_log)
47  { }
48 
50 
55  exprt dereference(const exprt &pointer, bool display_points_to_sets = false);
56 
61  try_add_offset_to_indices(const exprt &expr, const exprt &offset);
62 
64  class valuet
65  {
66  public:
70 
73  {
74  }
75  };
76 
77  static bool should_ignore_value(
78  const exprt &what,
80  const irep_idt &language_mode);
81 
82  static valuet build_reference_to(
83  const exprt &what,
84  const exprt &pointer,
85  const namespacet &ns);
86 
87  static bool dereference_type_compare(
88  const typet &object_type,
89  const typet &dereference_type,
90  const namespacet &ns);
91 
92  static bool memory_model(
93  exprt &value,
94  const typet &type,
95  const exprt &offset,
96  const namespacet &ns);
97 
98  static bool memory_model_bytes(
99  exprt &value,
100  const typet &type,
101  const exprt &offset,
102  const namespacet &ns);
103 
104 private:
105  const namespacet &ns;
114  const messaget &log;
115  valuet get_failure_value(const exprt &pointer, const typet &type);
117  const exprt &pointer,
118  bool display_points_to_sets);
119 };
120 
121 #endif // CPROVER_POINTER_ANALYSIS_VALUE_SET_DEREFERENCE_H
Base class for pointer value set analysis.
dstringt has one field, an unsigned integer no which is an index into a static table of strings.
Definition: dstring.h:37
Base class for all expressions.
Definition: expr.h:54
The Boolean constant false.
Definition: std_expr.h:2811
Class that provides messages with a built-in verbosity 'level'.
Definition: message.h:155
A namespacet is essentially one or two symbol tables bound together, to allow for symbol lookups in t...
Definition: namespace.h:91
The NIL expression.
Definition: std_expr.h:2820
The symbol table.
Definition: symbol_table.h:14
The type of an expression, extends irept.
Definition: type.h:28
Return value for build_reference_to; see that method for documentation.
Wrapper for a function dereferencing pointer expressions using a value set.
static bool memory_model_bytes(exprt &value, const typet &type, const exprt &offset, const namespacet &ns)
Replace value by an expression of type to_type corresponding to the value at memory address value + o...
valuet get_failure_value(const exprt &pointer, const typet &type)
exprt handle_dereference_base_case(const exprt &pointer, bool display_points_to_sets)
value_set_dereferencet(const namespacet &_ns, symbol_tablet &_new_symbol_table, dereference_callbackt &_dereference_callback, const irep_idt _language_mode, bool _exclude_null_derefs, const messaget &_log)
const bool exclude_null_derefs
Flag indicating whether value_set_dereferencet::dereference should disregard an apparent attempt to d...
static bool dereference_type_compare(const typet &object_type, const typet &dereference_type, const namespacet &ns)
Check if the two types have matching number of ID_pointer levels, with the dereference type eventuall...
dereference_callbackt & dereference_callback
exprt dereference(const exprt &pointer, bool display_points_to_sets=false)
Dereference the given pointer-expression.
const irep_idt language_mode
language_mode: ID_java, ID_C or another language identifier if we know the source language in use,...
static valuet build_reference_to(const exprt &what, const exprt &pointer, const namespacet &ns)
optionalt< exprt > try_add_offset_to_indices(const exprt &expr, const exprt &offset)
If expr is of the form (c1 ? e1[o1] : c2 ? e2[o2] : c3 ? ...) then return c1 ? e1[o1 + offset] : e2[o...
static bool should_ignore_value(const exprt &what, bool exclude_null_derefs, const irep_idt &language_mode)
Determine whether possible alias what should be ignored when replacing a pointer by its referees.
static bool memory_model(exprt &value, const typet &type, const exprt &offset, const namespacet &ns)
Replace value by an expression of type to_type corresponding to the value at memory address value + o...
nonstd::optional< T > optionalt
Definition: optional.h:35
API to expression classes.