lower_byte_operators.cpp File Reference

#include "arith_tools.h"
#include "bitvector_expr.h"
#include "byte_operators.h"
#include "c_types.h"
#include "endianness_map.h"
#include "expr_util.h"
#include "namespace.h"
#include "narrow.h"
#include "pointer_offset_size.h"
#include "simplify_expr.h"
#include "string_constant.h"
#include <algorithm>

Include dependency graph for lower_byte_operators.cpp:

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Classes
struct	boundst

Functions
static exprt	bv_to_expr (const exprt &bitvector_expr, const typet &target_type, const endianness_mapt &endianness_map, const namespacet &ns)
	Convert a bitvector-typed expression bitvector_expr to an expression of type target_type.
static boundst	map_bounds (const endianness_mapt &endianness_map, std::size_t lower_bound, std::size_t upper_bound)
	Map bit boundaries according to endianness.
bitvector_typet	adjust_width (const typet &src, std::size_t new_width)
	changes the width of the given bitvector type
static struct_exprt	bv_to_struct_expr (const exprt &bitvector_expr, const struct_typet &struct_type, const endianness_mapt &endianness_map, const namespacet &ns)
	Convert a bitvector-typed expression bitvector_expr to a struct-typed expression.
static exprt	bv_to_union_expr (const exprt &bitvector_expr, const union_typet &union_type, const endianness_mapt &endianness_map, const namespacet &ns)
	Convert a bitvector-typed expression bitvector_expr to a union-typed expression.
static array_exprt	bv_to_array_expr (const exprt &bitvector_expr, const array_typet &array_type, const endianness_mapt &endianness_map, const namespacet &ns)
	Convert a bitvector-typed expression bitvector_expr to an array-typed expression.
static vector_exprt	bv_to_vector_expr (const exprt &bitvector_expr, const vector_typet &vector_type, const endianness_mapt &endianness_map, const namespacet &ns)
	Convert a bitvector-typed expression bitvector_expr to a vector-typed expression.
static complex_exprt	bv_to_complex_expr (const exprt &bitvector_expr, const complex_typet &complex_type, const endianness_mapt &endianness_map, const namespacet &ns)
	Convert a bitvector-typed expression bitvector_expr to a complex-typed expression.
static exprt	unpack_rec (const exprt &src, bool little_endian, const std::optional< mp_integer > &offset_bytes, const std::optional< mp_integer > &max_bytes, const std::size_t bits_per_byte, const namespacet &ns, bool unpack_byte_array)
	Rewrite an object into its individual bytes.
static exprt::operandst	instantiate_byte_array (const exprt &src, std::size_t lower_bound, std::size_t upper_bound, const std::size_t bits_per_byte, const namespacet &ns)
	Build the individual bytes to be used in an update.
static exprt	unpack_array_vector_no_known_bounds (const exprt &src, std::size_t el_bytes, bool little_endian, const std::size_t bits_per_byte, const namespacet &ns)
	Rewrite an array or vector into its individual bytes when no maximum number of bytes is known.
static exprt	unpack_array_vector (const exprt &src, const std::optional< mp_integer > &src_size, const mp_integer &element_bits, bool little_endian, const std::optional< mp_integer > &offset_bytes, const std::optional< mp_integer > &max_bytes, const std::size_t bits_per_byte, const namespacet &ns)
	Rewrite an array or vector into its individual bytes.
static void	process_bit_fields (exprt::operandst &&bit_fields, std::size_t total_bits, exprt::operandst &dest, bool little_endian, const std::optional< mp_integer > &offset_bytes, const std::optional< mp_integer > &max_bytes, const std::size_t bits_per_byte, const namespacet &ns)
	Extract bytes from a sequence of bitvector-typed elements.
static array_exprt	unpack_struct (const exprt &src, bool little_endian, const std::optional< mp_integer > &offset_bytes, const std::optional< mp_integer > &max_bytes, const std::size_t bits_per_byte, const namespacet &ns)
	Rewrite a struct-typed expression into its individual bytes.
static array_exprt	unpack_complex (const exprt &src, bool little_endian, const std::size_t bits_per_byte, const namespacet &ns)
	Rewrite a complex_exprt into its individual bytes.
static exprt	lower_byte_extract_array_vector (const byte_extract_exprt &src, const byte_extract_exprt &unpacked, const typet &subtype, const mp_integer &element_bits, const namespacet &ns)
	Rewrite a byte extraction of an array/vector-typed result to byte extraction of the individual components that make up an array_exprt or vector_exprt.
static std::optional< exprt >	lower_byte_extract_complex (const byte_extract_exprt &src, const byte_extract_exprt &unpacked, const namespacet &ns)
	Rewrite a byte extraction of a complex-typed result to byte extraction of the individual components that make up a complex_exprt.
exprt	lower_byte_extract (const byte_extract_exprt &src, const namespacet &ns)
	rewrite byte extraction from an array to byte extraction from a concatenation of array index expressions
static exprt	lower_byte_update (const byte_update_exprt &src, const exprt &value_as_byte_array, const std::optional< exprt > &non_const_update_bound, const namespacet &ns)
	Apply a byte update src using the byte array value_as_byte_array as update value.
static exprt	lower_byte_update_byte_array_vector_non_const (const byte_update_exprt &src, const typet &subtype, const exprt &value_as_byte_array, const exprt &non_const_update_bound, const namespacet &ns)
	Apply a byte update src to an array/vector of bytes using the byte-array typed expression value_as_byte_array as update value.
static exprt	lower_byte_update_byte_array_vector (const byte_update_exprt &src, const typet &subtype, const array_exprt &value_as_byte_array, const std::optional< exprt > &non_const_update_bound, const namespacet &ns)
	Apply a byte update src to an array/vector of bytes using the byte array value_as_byte_array as update value.
static exprt	lower_byte_update_array_vector_unbounded (const byte_update_exprt &src, const typet &subtype, const exprt &subtype_size, const exprt &value_as_byte_array, const exprt &non_const_update_bound, const exprt &initial_bytes, const exprt &first_index, const exprt &first_update_value, const namespacet &ns)
	Apply a byte update src to an array/vector typed operand, using the byte array value_as_byte_array as update value, which has non-constant size.
static exprt	lower_byte_update_array_vector_non_const (const byte_update_exprt &src, const typet &subtype, const exprt &value_as_byte_array, const std::optional< exprt > &non_const_update_bound, const namespacet &ns)
	Apply a byte update src to an array/vector typed operand, using the byte array value_as_byte_array as update value, when either the size of each element or the overall array/vector size is not constant.
static exprt	lower_byte_update_single_element (const byte_update_exprt &src, const mp_integer &offset_bits, const exprt &element_to_update, const mp_integer &subtype_bits, const mp_integer &bits_already_set, const exprt &value_as_byte_array, const std::optional< exprt > &non_const_update_bound, const namespacet &ns)
	Byte update a struct/array/vector element.
static exprt	lower_byte_update_array_vector (const byte_update_exprt &src, const typet &subtype, const std::optional< mp_integer > &subtype_bits, const exprt &value_as_byte_array, const std::optional< exprt > &non_const_update_bound, const namespacet &ns)
	Apply a byte update src to an array/vector typed operand using the byte array value_as_byte_array as update value.
static exprt	lower_byte_update_struct (const byte_update_exprt &src, const struct_typet &struct_type, const exprt &value_as_byte_array, const std::optional< exprt > &non_const_update_bound, const namespacet &ns)
	Apply a byte update src to a struct typed operand using the byte array value_as_byte_array as update value.
static exprt	lower_byte_update_union (const byte_update_exprt &src, const union_typet &union_type, const exprt &value_as_byte_array, const std::optional< exprt > &non_const_update_bound, const namespacet &ns)
	Apply a byte update src to a union typed operand using the byte array value_as_byte_array as update value.
exprt	lower_byte_update (const byte_update_exprt &src, const namespacet &ns)
	Rewrite a byte update expression to more fundamental operations.
exprt	lower_byte_operators (const exprt &src, const namespacet &ns)
	Rewrite an expression possibly containing byte-extract or -update expressions to more fundamental operations.

Function Documentation

adjust_width()

bitvector_typet adjust_width	(	const typet &	src,
		std::size_t	new_width
	)

changes the width of the given bitvector type

Definition at line 59 of file lower_byte_operators.cpp.

bv_to_array_expr()

static array_exprt bv_to_array_expr ( const exprt &  bitvector_expr, const array_typet &  array_type, const endianness_mapt &  endianness_map, const namespacet &  ns  )

static

Convert a bitvector-typed expression bitvector_expr to an array-typed expression.

See bv_to_expr for an overview.

Definition at line 175 of file lower_byte_operators.cpp.

bv_to_complex_expr()

static complex_exprt bv_to_complex_expr ( const exprt &  bitvector_expr, const complex_typet &  complex_type, const endianness_mapt &  endianness_map, const namespacet &  ns  )

static

Convert a bitvector-typed expression bitvector_expr to a complex-typed expression.

See bv_to_expr for an overview.

Definition at line 275 of file lower_byte_operators.cpp.

bv_to_expr()

static exprt bv_to_expr ( const exprt &  bitvector_expr, const typet &  target_type, const endianness_mapt &  endianness_map, const namespacet &  ns  )

static

Convert a bitvector-typed expression bitvector_expr to an expression of type target_type.

If target_type is a bitvector type this may be a no-op or a typecast. For composite types such as structs, the bitvectors corresponding to the individual members are extracted and then a compound expression is built from those extracted members. When the size of a component isn't constant we fall back to computing its size based on the width of bitvector_expr.

Parameters

bitvector_expr	Bitvector-typed expression to extract from.
target_type	Type of the expression to build.
ns	Namespace to resolve tag types.
endianness_map	Endianness map.

Returns

Expression of type target_type constructed from sequences of bits from bitvector_expr.

Definition at line 330 of file lower_byte_operators.cpp.

bv_to_struct_expr()

static struct_exprt bv_to_struct_expr ( const exprt &  bitvector_expr, const struct_typet &  struct_type, const endianness_mapt &  endianness_map, const namespacet &  ns  )

static

Convert a bitvector-typed expression bitvector_expr to a struct-typed expression.

See bv_to_expr for an overview.

Definition at line 78 of file lower_byte_operators.cpp.

bv_to_union_expr()

static exprt bv_to_union_expr ( const exprt &  bitvector_expr, const union_typet &  union_type, const endianness_mapt &  endianness_map, const namespacet &  ns  )

static

Convert a bitvector-typed expression bitvector_expr to a union-typed expression.

See bv_to_expr for an overview.

Definition at line 127 of file lower_byte_operators.cpp.

bv_to_vector_expr()

static vector_exprt bv_to_vector_expr ( const exprt &  bitvector_expr, const vector_typet &  vector_type, const endianness_mapt &  endianness_map, const namespacet &  ns  )

static

Convert a bitvector-typed expression bitvector_expr to a vector-typed expression.

See bv_to_expr for an overview.

Definition at line 229 of file lower_byte_operators.cpp.

instantiate_byte_array()

static exprt::operandst instantiate_byte_array ( const exprt &  src, std::size_t  lower_bound, std::size_t  upper_bound, const std::size_t  bits_per_byte, const namespacet &  ns  )

static

Build the individual bytes to be used in an update.

Parameters

src	Source expression of array or vector type
lower_bound	First index into src to be included in the result
upper_bound	First index into src to be excluded from the result
bits_per_byte	number of bits that make up a byte
ns	Namespace

Returns

Sequence of bytes.

Definition at line 424 of file lower_byte_operators.cpp.

lower_byte_extract()

exprt lower_byte_extract	(	const byte_extract_exprt &	src,
		const namespacet &	ns
	)

rewrite byte extraction from an array to byte extraction from a concatenation of array index expressions

Rewrite a byte extract expression to more fundamental operations.

Definition at line 1215 of file lower_byte_operators.cpp.

lower_byte_extract_array_vector()

static exprt lower_byte_extract_array_vector ( const byte_extract_exprt &  src, const byte_extract_exprt &  unpacked, const typet &  subtype, const mp_integer &  element_bits, const namespacet &  ns  )

static

Rewrite a byte extraction of an array/vector-typed result to byte extraction of the individual components that make up an array_exprt or vector_exprt.

Parameters

src	Original byte extract expression
unpacked	Byte extraction with root operand expanded into array (via unpack_rec)
subtype	Array/vector element type
element_bits	bit width of array/vector elements
ns	Namespace

Returns

An array or vector expression.

Definition at line 1102 of file lower_byte_operators.cpp.

lower_byte_extract_complex()

static std::optional< exprt > lower_byte_extract_complex ( const byte_extract_exprt &  src, const byte_extract_exprt &  unpacked, const namespacet &  ns  )

static

Rewrite a byte extraction of a complex-typed result to byte extraction of the individual components that make up a complex_exprt.

Parameters

src	Original byte extract expression
unpacked	Byte extraction with root operand expanded into array (via unpack_rec)
ns	Namespace

Returns

An expression if the subtype size is known, else nullopt so that a fall-back to more generic code can be used.

Definition at line 1183 of file lower_byte_operators.cpp.

lower_byte_operators()

exprt lower_byte_operators	(	const exprt &	src,
		const namespacet &	ns
	)

Rewrite an expression possibly containing byte-extract or -update expressions to more fundamental operations.

Parameters

src	Input expression
ns	Namespace

Returns

Semantically equivalent expression that does not contain any byte_extract_exprt or byte_update_exprt.

Definition at line 2638 of file lower_byte_operators.cpp.

lower_byte_update() [1/2]

static exprt lower_byte_update ( const byte_update_exprt &  src, const exprt &  value_as_byte_array, const std::optional< exprt > &  non_const_update_bound, const namespacet &  ns  )

static

Apply a byte update src using the byte array value_as_byte_array as update value.

Parameters

src	Original byte-update expression
value_as_byte_array	Update value as an array of bytes
non_const_update_bound	If set, (symbolically) constrain updates such as to at most update non_const_update_bound elements
ns	Namespace

Returns

Expression reflecting all updates.

Definition at line 2316 of file lower_byte_operators.cpp.

lower_byte_update() [2/2]

exprt lower_byte_update	(	const byte_update_exprt &	src,
		const namespacet &	ns
	)

Rewrite a byte update expression to more fundamental operations.

Parameters

src	Byte update expression
ns	Namespace

Returns

Semantically equivalent expression such that the top-level expression no longer is a byte_extract_exprt or byte_update_exprt. Use lower_byte_operators to also remove all byte operators from any operands of src.

Definition at line 2545 of file lower_byte_operators.cpp.

lower_byte_update_array_vector()

static exprt lower_byte_update_array_vector ( const byte_update_exprt &  src, const typet &  subtype, const std::optional< mp_integer > &  subtype_bits, const exprt &  value_as_byte_array, const std::optional< exprt > &  non_const_update_bound, const namespacet &  ns  )

static

Apply a byte update src to an array/vector typed operand using the byte array value_as_byte_array as update value.

Parameters

src	Original byte-update expression
subtype	Array/vector element type
subtype_bits	Bit width of subtype
value_as_byte_array	Update value as an array of bytes
non_const_update_bound	If set, (symbolically) constrain updates such as to at most update non_const_update_bound elements
ns	Namespace

Returns

Array/vector expression reflecting all updates.

Definition at line 2096 of file lower_byte_operators.cpp.

lower_byte_update_array_vector_non_const()

static exprt lower_byte_update_array_vector_non_const ( const byte_update_exprt &  src, const typet &  subtype, const exprt &  value_as_byte_array, const std::optional< exprt > &  non_const_update_bound, const namespacet &  ns  )

static

Apply a byte update src to an array/vector typed operand, using the byte array value_as_byte_array as update value, when either the size of each element or the overall array/vector size is not constant.

Parameters

src	Original byte-update expression
subtype	Array/vector element type
value_as_byte_array	Update value as an array of bytes
non_const_update_bound	If set, (symbolically) constrain updates such as to at most update non_const_update_bound elements
ns	Namespace

Returns

Array/vector expression reflecting all updates.

Definition at line 1771 of file lower_byte_operators.cpp.

lower_byte_update_array_vector_unbounded()

static exprt lower_byte_update_array_vector_unbounded ( const byte_update_exprt &  src, const typet &  subtype, const exprt &  subtype_size, const exprt &  value_as_byte_array, const exprt &  non_const_update_bound, const exprt &  initial_bytes, const exprt &  first_index, const exprt &  first_update_value, const namespacet &  ns  )

static

Apply a byte update src to an array/vector typed operand, using the byte array value_as_byte_array as update value, which has non-constant size.

Parameters

src	Original byte-update expression
subtype	Array/vector element type
subtype_size	Size (in bytes) of subtype
value_as_byte_array	Update value as an array of bytes
non_const_update_bound	Constrain updates such as to at most update non_const_update_bound elements
initial_bytes	Number of bytes from value_as_byte_array to use to update the array/vector element at first_index
first_index	Lowest index into the target array/vector of the update
first_update_value	Combined value of partially old and updated bytes to use at first_index
ns	Namespace

Returns

Array comprehension reflecting all updates.

Definition at line 1631 of file lower_byte_operators.cpp.

lower_byte_update_byte_array_vector()

static exprt lower_byte_update_byte_array_vector ( const byte_update_exprt &  src, const typet &  subtype, const array_exprt &  value_as_byte_array, const std::optional< exprt > &  non_const_update_bound, const namespacet &  ns  )

static

Apply a byte update src to an array/vector of bytes using the byte array value_as_byte_array as update value.

Parameters

src	Original byte-update expression
subtype	Array/vector element type
value_as_byte_array	Update value as an array of bytes
non_const_update_bound	If set, (symbolically) constrain updates such as to at most update non_const_update_bound elements
ns	Namespace

Returns

Array/vector expression reflecting all updates.

Definition at line 1558 of file lower_byte_operators.cpp.

lower_byte_update_byte_array_vector_non_const()

static exprt lower_byte_update_byte_array_vector_non_const ( const byte_update_exprt &  src, const typet &  subtype, const exprt &  value_as_byte_array, const exprt &  non_const_update_bound, const namespacet &  ns  )

static

Apply a byte update src to an array/vector of bytes using the byte-array typed expression value_as_byte_array as update value.

Parameters

src	Original byte-update expression
subtype	Array/vector element type
value_as_byte_array	Update value as an array of bytes
non_const_update_bound	Constrain updates such as to at most update non_const_update_bound elements
ns	Namespace

Returns

Array comprehension reflecting all updates.

Definition at line 1489 of file lower_byte_operators.cpp.

lower_byte_update_single_element()

static exprt lower_byte_update_single_element ( const byte_update_exprt &  src, const mp_integer &  offset_bits, const exprt &  element_to_update, const mp_integer &  subtype_bits, const mp_integer &  bits_already_set, const exprt &  value_as_byte_array, const std::optional< exprt > &  non_const_update_bound, const namespacet &  ns  )

static

Byte update a struct/array/vector element.

Parameters

src	Original byte-update expression
offset_bits	Offset in src expressed as bits
element_to_update	struct/array/vector element
subtype_bits	Bit width of element_to_update
bits_already_set	Number of bits in the original target object that have been updated already
value_as_byte_array	Update value as an array of bytes
non_const_update_bound	If set, (symbolically) constrain updates such as to at most update non_const_update_bound elements
ns	Namespace

Returns

Array/vector expression reflecting all updates.

Definition at line 1921 of file lower_byte_operators.cpp.

lower_byte_update_struct()

static exprt lower_byte_update_struct ( const byte_update_exprt &  src, const struct_typet &  struct_type, const exprt &  value_as_byte_array, const std::optional< exprt > &  non_const_update_bound, const namespacet &  ns  )

static

Apply a byte update src to a struct typed operand using the byte array value_as_byte_array as update value.

Parameters

src	Original byte-update expression
struct_type	Type of the operand
value_as_byte_array	Update value as an array of bytes
non_const_update_bound	If set, (symbolically) constrain updates such as to at most update non_const_update_bound elements
ns	Namespace

Returns

Struct expression reflecting all updates.

Definition at line 2180 of file lower_byte_operators.cpp.

lower_byte_update_union()

static exprt lower_byte_update_union ( const byte_update_exprt &  src, const union_typet &  union_type, const exprt &  value_as_byte_array, const std::optional< exprt > &  non_const_update_bound, const namespacet &  ns  )

static

Apply a byte update src to a union typed operand using the byte array value_as_byte_array as update value.

Parameters

src	Original byte-update expression
union_type	Type of the operand
value_as_byte_array	Update value as an array of bytes
non_const_update_bound	If set, (symbolically) constrain updates such as to at most update non_const_update_bound elements
ns	Namespace

Returns

Union expression reflecting all updates.

Definition at line 2284 of file lower_byte_operators.cpp.

map_bounds()

static boundst map_bounds ( const endianness_mapt &  endianness_map, std::size_t  lower_bound, std::size_t  upper_bound  )

static

Map bit boundaries according to endianness.

Definition at line 36 of file lower_byte_operators.cpp.

process_bit_fields()

static void process_bit_fields ( exprt::operandst &&  bit_fields, std::size_t  total_bits, exprt::operandst &  dest, bool  little_endian, const std::optional< mp_integer > &  offset_bytes, const std::optional< mp_integer > &  max_bytes, const std::size_t  bits_per_byte, const namespacet &  ns  )

static

Extract bytes from a sequence of bitvector-typed elements.

Parameters

	bit_fields	operands to concatenate
	total_bits	total bit width of operands
[out]	dest	target to append unpacked bytes to
	little_endian	true, iff assumed endianness is little-endian
	offset_bytes	if set, bytes prior to this offset will be filled with nil values
	max_bytes	if set, use as upper bound of the number of bytes to unpack
	bits_per_byte	number of bits that make up a byte
	ns	namespace for type lookups

Definition at line 652 of file lower_byte_operators.cpp.

unpack_array_vector()

static exprt unpack_array_vector ( const exprt &  src, const std::optional< mp_integer > &  src_size, const mp_integer &  element_bits, bool  little_endian, const std::optional< mp_integer > &  offset_bytes, const std::optional< mp_integer > &  max_bytes, const std::size_t  bits_per_byte, const namespacet &  ns  )

static

Rewrite an array or vector into its individual bytes.

Parameters

src	array/vector to unpack
src_size	number of elements in src, if the array/vector size is constant; if the array/vector size is not constant (and this argument thus not set), max_bytes needs to be a known constant value to build an array expression, else we fall back to building an array comprehension
element_bits	bit width of array/vector elements
little_endian	true, iff assumed endianness is little-endian
offset_bytes	if set, bytes prior to this offset will be filled with nil values
max_bytes	if set, use as upper bound of the number of bytes to unpack
bits_per_byte	number of bits that make up a byte
ns	namespace for type lookups

Returns

Array expression holding unpacked elements or array comprehension

Definition at line 537 of file lower_byte_operators.cpp.

unpack_array_vector_no_known_bounds()

static exprt unpack_array_vector_no_known_bounds ( const exprt &  src, std::size_t  el_bytes, bool  little_endian, const std::size_t  bits_per_byte, const namespacet &  ns  )

static

Rewrite an array or vector into its individual bytes when no maximum number of bytes is known.

Parameters

src	array/vector to unpack
el_bytes	byte width of array/vector elements
little_endian	true, iff assumed endianness is little-endian
bits_per_byte	number of bits that make up a byte
ns	namespace for type lookups

Returns

Array expression holding unpacked elements or array comprehension

Definition at line 468 of file lower_byte_operators.cpp.

unpack_complex()

static array_exprt unpack_complex ( const exprt &  src, bool  little_endian, const std::size_t  bits_per_byte, const namespacet &  ns  )

static

Rewrite a complex_exprt into its individual bytes.

Parameters

src	complex-typed expression to unpack
little_endian	true, iff assumed endianness is little-endian
bits_per_byte	number of bits that make up a byte
ns	namespace for type lookups

Returns

array_exprt holding unpacked elements

Definition at line 843 of file lower_byte_operators.cpp.

unpack_rec()

static exprt unpack_rec ( const exprt &  src, bool  little_endian, const std::optional< mp_integer > &  offset_bytes, const std::optional< mp_integer > &  max_bytes, const std::size_t  bits_per_byte, const namespacet &  ns, bool  unpack_byte_array  )

static

Rewrite an object into its individual bytes.

Parameters

src	object to unpack
little_endian	true, iff assumed endianness is little-endian
offset_bytes	if set, bytes prior to this offset will be filled with nil values
max_bytes	if set, use as upper bound of the number of bytes to unpack
bits_per_byte	number of bits that make up a byte
ns	namespace for type lookups
unpack_byte_array	if true, return unmodified src iff it is an

Returns

array of bytes in the sequence found in memory

Definition at line 897 of file lower_byte_operators.cpp.

unpack_struct()

static array_exprt unpack_struct ( const exprt &  src, bool  little_endian, const std::optional< mp_integer > &  offset_bytes, const std::optional< mp_integer > &  max_bytes, const std::size_t  bits_per_byte, const namespacet &  ns  )

static

Rewrite a struct-typed expression into its individual bytes.

Parameters

src	struct-typed expression to unpack
little_endian	true, iff assumed endianness is little-endian
offset_bytes	if set, bytes prior to this offset will be filled with nil values
max_bytes	if set, use as upper bound of the number of bytes to unpack
bits_per_byte	number of bits that make up a byte
ns	namespace for type lookups

Returns

array_exprt holding unpacked elements

Definition at line 690 of file lower_byte_operators.cpp.