CBMC
value_set_dereference.cpp File Reference

Symbolic Execution of ANSI-C. More...

#include "value_set_dereference.h"
#include <util/arith_tools.h>
#include <util/byte_operators.h>
#include <util/c_types.h>
#include <util/config.h>
#include <util/cprover_prefix.h>
#include <util/expr_iterator.h>
#include <util/expr_util.h>
#include <util/format_expr.h>
#include <util/fresh_symbol.h>
#include <util/json.h>
#include <util/message.h>
#include <util/namespace.h>
#include <util/pointer_expr.h>
#include <util/pointer_offset_size.h>
#include <util/pointer_predicates.h>
#include <util/range.h>
#include <util/simplify_expr.h>
#include <util/symbol.h>
#include "dereference_callback.h"
#include <deque>
+ Include dependency graph for value_set_dereference.cpp:

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Functions

static bool should_use_local_definition_for (const exprt &expr)
 Returns true if expr is complicated enough that a local definition (using a let expression) is preferable to repeating it, potentially many times. More...
 
static json_objectt value_set_dereference_stats_to_json (const exprt &pointer, const std::vector< exprt > &points_to_set, const std::vector< exprt > &retained_values, const exprt &value)
 
static std::optional< exprttry_add_offset_to_indices (const exprt &expr, const exprt &offset_elements)
 If expr is of the form (c1 ? e1[o1] : c2 ? e2[o2] : c3 ? ...) then return c1 ? e1[o1 + offset] : e2[o2 + offset] : c3 ? ... otherwise return an empty std::optional. More...
 
static bool is_a_bv_type (const typet &type)
 

Detailed Description

Symbolic Execution of ANSI-C.

Definition in file value_set_dereference.cpp.

Function Documentation

◆ is_a_bv_type()

static bool is_a_bv_type ( const typet type)
static

Definition at line 686 of file value_set_dereference.cpp.

◆ should_use_local_definition_for()

static bool should_use_local_definition_for ( const exprt expr)
static

Returns true if expr is complicated enough that a local definition (using a let expression) is preferable to repeating it, potentially many times.

Of course this is just a heuristic – currently we allow any expression that only involves one symbol, such as "x", "(type*)x", "x[0]" (but not "x[y]"). Particularly we want to make sure to insist on a local definition of expr is a large if-expression, such as p == &o1 ? o1 : p == &o2 ? o2 : ..., as can result from dereferencing a subexpression (though note that value_set_dereferencet::dereference special-cases if_exprt, and therefore handles the specific case of a double-dereference (**p) without an intervening member operator, typecast, pointer arithmetic, etc.)

Definition at line 51 of file value_set_dereference.cpp.

◆ try_add_offset_to_indices()

static std::optional<exprt> try_add_offset_to_indices ( const exprt expr,
const exprt offset_elements 
)
static

If expr is of the form (c1 ? e1[o1] : c2 ? e2[o2] : c3 ? ...) then return c1 ? e1[o1 + offset] : e2[o2 + offset] : c3 ? ... otherwise return an empty std::optional.

Definition at line 108 of file value_set_dereference.cpp.

◆ value_set_dereference_stats_to_json()

static json_objectt value_set_dereference_stats_to_json ( const exprt pointer,
const std::vector< exprt > &  points_to_set,
const std::vector< exprt > &  retained_values,
const exprt value 
)
static

Definition at line 68 of file value_set_dereference.cpp.