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/*******************************************************************\
Module: Unit tests for byte_extract/byte_update lowering
Author: Michael Tautschnig
\*******************************************************************/
#include <util/arith_tools.h>
#include <util/byte_operators.h>
#include <util/c_types.h>
#include <util/cmdline.h>
#include <util/config.h>
#include <util/expr_util.h>
#include <util/namespace.h>
#include <util/pointer_offset_size.h>
#include <util/simplify_expr.h>
#include <util/simplify_utils.h>
#include <util/std_types.h>
#include <util/string_constant.h>
#include <util/symbol_table.h>
#include <testing-utils/use_catch.h>
TEST_CASE("byte extract and bits", "[core][util][lowering][byte_extract]")
{
// this test does require a proper architecture to be set so that byte extract
// uses adequate endianness
cmdlinet cmdline;
config.set(cmdline);
const symbol_tablet symbol_table;
const namespacet ns(symbol_table);
const unsignedbv_typet u16{16};
const exprt sixteen_bits = from_integer(0x1234, u16);
const array_typet bit_array_type{bv_typet{1}, from_integer(16, size_type())};
bool little_endian;
GIVEN("Little endian")
{
little_endian = true;
const auto bit_string = expr2bits(sixteen_bits, little_endian, ns);
REQUIRE(bit_string.has_value());
REQUIRE(bit_string->size() == 16);
const auto array_of_bits =
bits2expr(*bit_string, bit_array_type, little_endian, ns);
REQUIRE(array_of_bits.has_value());
const auto bit_string2 = expr2bits(*array_of_bits, little_endian, ns);
REQUIRE(bit_string2.has_value());
REQUIRE(*bit_string == *bit_string2);
const byte_extract_exprt be1{
little_endian ? ID_byte_extract_little_endian
: ID_byte_extract_big_endian,
sixteen_bits,
from_integer(0, c_index_type()),
config.ansi_c.char_width,
bit_array_type};
const exprt lower_be1 = lower_byte_extract(be1, ns);
REQUIRE(lower_be1 == *array_of_bits);
}
GIVEN("Big endian")
{
little_endian = false;
const auto bit_string = expr2bits(sixteen_bits, little_endian, ns);
REQUIRE(bit_string.has_value());
REQUIRE(bit_string->size() == 16);
const auto array_of_bits =
bits2expr(*bit_string, bit_array_type, little_endian, ns);
REQUIRE(array_of_bits.has_value());
const auto bit_string2 = expr2bits(*array_of_bits, little_endian, ns);
REQUIRE(bit_string2.has_value());
REQUIRE(*bit_string == *bit_string2);
const byte_extract_exprt be1{
little_endian ? ID_byte_extract_little_endian
: ID_byte_extract_big_endian,
sixteen_bits,
from_integer(0, c_index_type()),
config.ansi_c.char_width,
bit_array_type};
const exprt lower_be1 = lower_byte_extract(be1, ns);
REQUIRE(lower_be1 == *array_of_bits);
}
}
SCENARIO("byte_extract_lowering", "[core][util][lowering][byte_extract]")
{
// this test does require a proper architecture to be set so that byte extract
// uses adequate endianness
cmdlinet cmdline;
config.set(cmdline);
const symbol_tablet symbol_table;
const namespacet ns(symbol_table);
GIVEN("A byte_extract over a POD")
{
const exprt deadbeef = from_integer(0xdeadbeef, unsignedbv_typet(32));
const byte_extract_exprt be1(
ID_byte_extract_little_endian,
deadbeef,
from_integer(1, c_index_type()),
config.ansi_c.char_width,
signedbv_typet(config.ansi_c.char_width));
THEN("byte_extract lowering yields the expected value")
{
const exprt lower_be1 = lower_byte_extract(be1, ns);
const exprt lower_be1_s = simplify_expr(lower_be1, ns);
REQUIRE(!has_subexpr(lower_be1, ID_byte_extract_little_endian));
REQUIRE(lower_be1.type() == be1.type());
REQUIRE(lower_be1_s == from_integer(0xbe, signedbv_typet(8)));
byte_extract_exprt be2 = be1;
be2.id(ID_byte_extract_big_endian);
const exprt lower_be2 = lower_byte_extract(be2, ns);
const exprt lower_be2_s = simplify_expr(lower_be2, ns);
REQUIRE(!has_subexpr(lower_be2, ID_byte_extract_big_endian));
REQUIRE(lower_be2.type() == be2.type());
REQUIRE(lower_be2_s == from_integer(0xad, signedbv_typet(8)));
}
}
GIVEN("A an unbounded byte_extract over a bounded operand")
{
const exprt deadbeef = from_integer(0xdeadbeef, unsignedbv_typet(32));
const byte_extract_exprt be1(
ID_byte_extract_little_endian,
deadbeef,
from_integer(1, c_index_type()),
config.ansi_c.char_width,
struct_typet(
{{"unbounded_array",
array_typet(
unsignedbv_typet(16), exprt(ID_infinity, size_type()))}}));
THEN("byte_extract lowering does not raise an exception")
{
const exprt lower_be1 = lower_byte_extract(be1, ns);
REQUIRE(!has_subexpr(lower_be1, ID_byte_extract_little_endian));
REQUIRE(lower_be1.type() == be1.type());
byte_extract_exprt be2 = be1;
be2.id(ID_byte_extract_big_endian);
const exprt lower_be2 = lower_byte_extract(be2, ns);
REQUIRE(!has_subexpr(lower_be2, ID_byte_extract_big_endian));
REQUIRE(lower_be2.type() == be2.type());
}
}
GIVEN("A an unbounded union byte_extract over a bounded operand")
{
const exprt deadbeef = from_integer(0xdeadbeef, unsignedbv_typet(32));
const byte_extract_exprt be1(
ID_byte_extract_little_endian,
deadbeef,
from_integer(1, c_index_type()),
config.ansi_c.char_width,
union_typet(
{{"unbounded_array",
array_typet(
unsignedbv_typet(16), exprt(ID_infinity, size_type()))}}));
THEN("byte_extract lowering does not raise an exception")
{
const exprt lower_be1 = lower_byte_extract(be1, ns);
REQUIRE(!has_subexpr(lower_be1, ID_byte_extract_little_endian));
REQUIRE(lower_be1.type() == be1.type());
byte_extract_exprt be2 = be1;
be2.id(ID_byte_extract_big_endian);
const exprt lower_be2 = lower_byte_extract(be2, ns);
REQUIRE(!has_subexpr(lower_be2, ID_byte_extract_big_endian));
REQUIRE(lower_be2.type() == be2.type());
}
}
GIVEN("A an empty union byte_extract over a bounded operand")
{
const exprt deadbeef = from_integer(0xdeadbeef, unsignedbv_typet(32));
const byte_extract_exprt be1(
ID_byte_extract_little_endian,
deadbeef,
from_integer(1, c_index_type()),
config.ansi_c.char_width,
union_typet{});
THEN("byte_extract lowering does not raise an exception")
{
const exprt lower_be1 = lower_byte_extract(be1, ns);
REQUIRE(!has_subexpr(lower_be1, ID_byte_extract_little_endian));
REQUIRE(lower_be1.type() == be1.type());
byte_extract_exprt be2 = be1;
be2.id(ID_byte_extract_big_endian);
const exprt lower_be2 = lower_byte_extract(be2, ns);
REQUIRE(!has_subexpr(lower_be2, ID_byte_extract_big_endian));
REQUIRE(lower_be2.type() == be2.type());
}
}
GIVEN("A a byte_extract from a string constant")
{
string_constantt s("ABCD");
const byte_extract_exprt be1(
ID_byte_extract_little_endian,
s,
from_integer(1, c_index_type()),
config.ansi_c.char_width,
unsignedbv_typet(16));
THEN("byte_extract lowering yields the expected value")
{
const exprt lower_be1 = lower_byte_extract(be1, ns);
REQUIRE(!has_subexpr(lower_be1, ID_byte_extract_little_endian));
REQUIRE(lower_be1.type() == be1.type());
REQUIRE(
lower_be1 == from_integer((int{'C'} << 8) + 'B', unsignedbv_typet(16)));
byte_extract_exprt be2 = be1;
be2.id(ID_byte_extract_big_endian);
const exprt lower_be2 = lower_byte_extract(be2, ns);
REQUIRE(!has_subexpr(lower_be2, ID_byte_extract_big_endian));
REQUIRE(lower_be2.type() == be2.type());
REQUIRE(
lower_be2 == from_integer((int{'B'} << 8) + 'C', unsignedbv_typet(16)));
}
}
GIVEN("A collection of types")
{
unsignedbv_typet u8(8);
signedbv_typet s8(8);
unsignedbv_typet u16(16);
signedbv_typet s16(16);
unsignedbv_typet u32(32);
signedbv_typet s32(32);
unsignedbv_typet u64(64);
signedbv_typet s64(64);
constant_exprt size = from_integer(8, size_type());
std::vector<typet> types = {
struct_typet({{"comp1", u16}, {"comp2", u16}}),
struct_typet({{"comp1", u32}, {"comp2", u64}}),
struct_typet(
{{"comp1", u32},
{"compX", c_bit_field_typet(u8, 4)},
{"pad", c_bit_field_typet(u8, 4)},
{"comp2", u8}}),
union_typet({{"compA", u32}, {"compB", u64}}),
c_enum_typet(u16),
c_enum_typet(unsignedbv_typet(128)),
array_typet(u8, size),
array_typet(s32, size),
array_typet(u64, size),
unsignedbv_typet(24),
unsignedbv_typet(128),
signedbv_typet(24),
signedbv_typet(128),
ieee_float_spect::single_precision().to_type(),
// generates the correct value, but remains wrapped in a typecast
// pointer_typet(u64, sizeof(void *) * CHAR_BIT),
vector_typet(size_type(), u8, size),
vector_typet(size_type(), u64, size),
complex_typet(s16),
complex_typet(u64)};
THEN("byte_extract lowering yields the expected value")
{
for(const auto &endianness :
{ID_byte_extract_little_endian, ID_byte_extract_big_endian})
{
for(const auto &t1 : types)
{
std::ostringstream oss;
for(int i = 0; i < 64; ++i)
{
std::string bits = integer2binary(i, 8);
std::reverse(bits.begin(), bits.end());
oss << bits;
}
const auto type_bits = pointer_offset_bits(t1, ns);
REQUIRE(type_bits);
const auto type_bits_int = numeric_cast_v<std::size_t>(*type_bits);
REQUIRE(type_bits_int <= oss.str().size());
const auto s = bits2expr(
oss.str().substr(0, type_bits_int),
t1,
endianness == ID_byte_extract_little_endian,
ns);
REQUIRE(s.has_value());
for(const auto &t2 : types)
{
oss.str("");
for(int i = 2; i < 64; ++i)
{
std::string bits = integer2binary(i, 8);
std::reverse(bits.begin(), bits.end());
oss << bits;
}
const auto type_bits_2 = pointer_offset_bits(t2, ns);
REQUIRE(type_bits_2);
// for now only extract within bounds
if(*type_bits_2 + 16 > *type_bits)
continue;
const auto type_bits_2_int =
numeric_cast_v<std::size_t>(*type_bits_2);
REQUIRE(type_bits_2_int <= oss.str().size());
const auto r = bits2expr(
oss.str().substr(0, type_bits_2_int),
t2,
endianness == ID_byte_extract_little_endian,
ns);
REQUIRE(r.has_value());
const byte_extract_exprt be(
endianness,
*s,
from_integer(2, c_index_type()),
config.ansi_c.char_width,
t2);
const exprt lower_be = lower_byte_extract(be, ns);
const exprt lower_be_s = simplify_expr(lower_be, ns);
REQUIRE(!has_subexpr(lower_be, ID_byte_extract_little_endian));
REQUIRE(!has_subexpr(lower_be, ID_byte_extract_big_endian));
REQUIRE(lower_be.type() == be.type());
REQUIRE(lower_be == *r);
REQUIRE(lower_be_s == *r);
}
}
}
}
}
}
SCENARIO("byte_update_lowering", "[core][util][lowering][byte_update]")
{
// this test does require a proper architecture to be set so that byte extract
// uses adequate endianness
cmdlinet cmdline;
config.set(cmdline);
const symbol_tablet symbol_table;
const namespacet ns(symbol_table);
GIVEN("A byte_update of a POD")
{
const exprt deadbeef = from_integer(0xdeadbeef, unsignedbv_typet(32));
const byte_update_exprt bu1(
ID_byte_update_little_endian,
deadbeef,
from_integer(1, c_index_type()),
from_integer(0x42, unsignedbv_typet(8)),
config.ansi_c.char_width);
THEN("byte_update lowering yields the expected value")
{
const exprt lower_bu1 = lower_byte_operators(bu1, ns);
const exprt lower_bu1_s = simplify_expr(lower_bu1, ns);
REQUIRE(!has_subexpr(lower_bu1, ID_byte_extract_little_endian));
REQUIRE(!has_subexpr(lower_bu1, ID_byte_update_little_endian));
REQUIRE(lower_bu1.type() == bu1.type());
REQUIRE(lower_bu1_s == from_integer(0xdead42ef, unsignedbv_typet(32)));
byte_update_exprt bu2 = bu1;
bu2.id(ID_byte_update_big_endian);
const exprt lower_bu2 = lower_byte_operators(bu2, ns);
const exprt lower_bu2_s = simplify_expr(lower_bu2, ns);
REQUIRE(!has_subexpr(lower_bu2, ID_byte_extract_big_endian));
REQUIRE(!has_subexpr(lower_bu2, ID_byte_update_big_endian));
REQUIRE(lower_bu2.type() == bu2.type());
REQUIRE(lower_bu2_s == from_integer(0xde42beef, unsignedbv_typet(32)));
}
}
GIVEN("A collection of types")
{
unsignedbv_typet u8(8);
signedbv_typet s8(8);
unsignedbv_typet u16(16);
signedbv_typet s16(16);
unsignedbv_typet u32(32);
signedbv_typet s32(32);
unsignedbv_typet u64(64);
signedbv_typet s64(64);
constant_exprt size = from_integer(8, size_type());
std::vector<typet> types = {
struct_typet({{"comp1", u16}, {"comp2", u16}}),
struct_typet({{"comp1", u32}, {"comp2", u64}}),
struct_typet(
{{"comp1", u32},
{"compX", c_bit_field_typet(u8, 4)},
{"pad", c_bit_field_typet(u8, 4)},
{"comp2", u8}}),
union_typet({{"compA", u32}, {"compB", u64}}),
c_enum_typet(u16),
c_enum_typet(unsignedbv_typet(128)),
array_typet(u8, size),
array_typet(s32, size),
array_typet(u64, size),
unsignedbv_typet(24),
unsignedbv_typet(128),
signedbv_typet(24),
signedbv_typet(128),
ieee_float_spect::single_precision().to_type(),
// generates the correct value, but remains wrapped in a typecast
// pointer_typet(u64, sizeof(void *) * CHAR_BIT),
vector_typet(size_type(), u8, size),
vector_typet(size_type(), u64, size),
// complex_typet(s16),
// complex_typet(u64)
};
THEN("byte_update lowering yields the expected value")
{
for(const auto &endianness :
{ID_byte_update_little_endian, ID_byte_update_big_endian})
{
for(const auto &t1 : types)
{
std::ostringstream oss;
for(int i = 0; i < 64; ++i)
{
std::string bits = integer2binary(i, 8);
std::reverse(bits.begin(), bits.end());
oss << bits;
}
const auto type_bits = pointer_offset_bits(t1, ns);
REQUIRE(type_bits);
const auto type_bits_int = numeric_cast_v<std::size_t>(*type_bits);
REQUIRE(type_bits_int <= oss.str().size());
const std::string s_string = oss.str().substr(0, type_bits_int);
const auto s = bits2expr(
s_string, t1, endianness == ID_byte_update_little_endian, ns);
REQUIRE(s.has_value());
for(const auto &t2 : types)
{
oss.str("");
for(int i = 64; i < 128; ++i)
{
std::string bits = integer2binary(i, 8);
std::reverse(bits.begin(), bits.end());
oss << bits;
}
const auto type_bits_2 = pointer_offset_bits(t2, ns);
REQUIRE(type_bits_2);
// for now only update within bounds
if(*type_bits_2 + 16 > *type_bits)
continue;
const auto type_bits_2_int =
numeric_cast_v<std::size_t>(*type_bits_2);
REQUIRE(type_bits_2_int <= oss.str().size());
const std::string u_string = oss.str().substr(0, type_bits_2_int);
const auto u = bits2expr(
u_string, t2, endianness == ID_byte_update_little_endian, ns);
REQUIRE(u.has_value());
std::string r_string = s_string;
r_string.replace(16, u_string.size(), u_string);
const auto r = bits2expr(
r_string, t1, endianness == ID_byte_update_little_endian, ns);
REQUIRE(r.has_value());
const byte_update_exprt bu(
endianness,
*s,
from_integer(2, c_index_type()),
*u,
config.ansi_c.char_width);
const exprt lower_bu = lower_byte_operators(bu, ns);
const exprt lower_bu_s = simplify_expr(lower_bu, ns);
REQUIRE(!has_subexpr(lower_bu, endianness));
REQUIRE(!has_subexpr(lower_bu, ID_byte_extract_big_endian));
REQUIRE(!has_subexpr(lower_bu, ID_byte_extract_little_endian));
REQUIRE(lower_bu.type() == bu.type());
REQUIRE(lower_bu == *r);
REQUIRE(lower_bu_s == *r);
}
}
}
}
}
}
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