bool to_integer(const exprt &expr, mp_integer &int_value)
{
if(!expr.is_constant())
return true;
const std::string &value = expr.value().as_string();
const irep_idt &type_id = expr.type().id();
if(type_id == "pointer")
{
if(value == "NULL")
{
int_value = 0;
return false;
}
}
else if(type_id == "c_enum" || type_id == "symbol")
{
int_value = string2integer(value);
return false;
}
else if(type_id == "unsignedbv")
{
int_value = binary2integer(value, false);
return false;
}
else if(type_id == "signedbv")
{
int_value = binary2integer(value, true);
return false;
}
return true;
}
void convert_integer_literal(
const std::string &src,
exprt &dest,
unsigned base)
{
bool is_unsigned=false;
unsigned long_cnt=0;
for(unsigned i=src.size(); i!=0; i--)
{
char ch=src[i-1];
if(ch=='u' || ch=='U')
is_unsigned=true;
else if(ch=='l' || ch=='L')
long_cnt++;
else
break;
}
mp_integer value;
if(base==10)
{
dest.value(src);
value=string2integer(src, 10);
}
else if(base==8)
{
dest.hex_or_oct(true);
value=string2integer(src, 8);
}
else
{
dest.hex_or_oct(true);
std::string without_prefix(src, 2, std::string::npos);
value=string2integer(without_prefix, 16);
}
typet type;
irep_idt cpp_type;
if(is_unsigned)
type=typet("unsignedbv");
else
type=typet("signedbv");
if(long_cnt==0) {
type.width(config.ansi_c.int_width);
if(!is_unsigned)
cpp_type="signed_int";
else
cpp_type="unsigned_int";
} else if(long_cnt==1) {
type.width(config.ansi_c.long_int_width);
if(!is_unsigned)
cpp_type="signed_long_int";
else
cpp_type="unsigned_long_int";
} else {
type.width(config.ansi_c.long_long_int_width);
if(!is_unsigned)
cpp_type="signed_long_long_int";
else
cpp_type="unsigned_long_long_int";
}
type.set("#cpp_type", cpp_type);
dest=from_integer(value, type);
dest.cformat(src);
}
bool c_typecheck_baset::zero_initializer(exprt &value, const typet &type) const
{
const std::string &type_id = type.id_string();
if(type_id == "bool")
{
value.make_false();
return false;
}
if(
type_id == "unsignedbv" || type_id == "signedbv" || type_id == "floatbv" ||
type_id == "fixedbv" || type_id == "pointer")
{
value = gen_zero(type);
return false;
}
else if(type_id == "code")
return false;
else if(type_id == "c_enum" || type_id == "incomplete_c_enum")
{
value = exprt("constant", type);
value.value(i2string(0));
return false;
}
else if(type_id == "array")
{
const array_typet &array_type = to_array_type(type);
exprt tmpval;
if(zero_initializer(tmpval, array_type.subtype()))
return true;
const exprt &size_expr = array_type.size();
if(size_expr.id() == "infinity")
{
}
else
{
mp_integer size;
if(to_integer(size_expr, size))
return true;
// Permit GCC zero sized arrays; disallow negative sized arrays.
// Cringe slightly when doing it though.
if(size < 0)
return true;
}
value = exprt("array_of", type);
value.move_to_operands(tmpval);
return false;
}
else if(type_id == "struct")
{
const irept::subt &components = type.components().get_sub();
value = exprt("struct", type);
forall_irep(it, components)
{
exprt tmp;
if(zero_initializer(tmp, (const typet &)it->type()))
return true;
value.move_to_operands(tmp);
}
return false;
}
void convert_float_literal(const std::string &src, exprt &dest)
{
mp_integer significand;
mp_integer exponent;
bool is_float, is_long;
unsigned base;
parse_float(src, significand, exponent, base, is_float, is_long);
dest = exprt("constant");
dest.cformat(src);
if(is_float)
{
dest.type() = float_type();
dest.type().set("#cpp_type", "float");
}
else if(is_long)
{
dest.type() = long_double_type();
dest.type().set("#cpp_type", "long_double");
}
else
{
dest.type() = double_type();
dest.type().set("#cpp_type", "double");
}
if(config.ansi_c.use_fixed_for_float)
{
unsigned width = atoi(dest.type().width().c_str());
unsigned fraction_bits;
const std::string &integer_bits = dest.type().integer_bits().as_string();
if(integer_bits == "")
fraction_bits = width / 2;
else
fraction_bits = width - atoi(integer_bits.c_str());
mp_integer factor = mp_integer(1) << fraction_bits;
mp_integer value = significand * factor;
if(value != 0)
{
if(exponent < 0)
value /= power(base, -exponent);
else
{
value *= power(base, exponent);
if(value >= power(2, width - 1))
{
// saturate: use "biggest value"
value = power(2, width - 1) - 1;
}
else if(value <= -power(2, width - 1) - 1)
{
// saturate: use "smallest value"
value = -power(2, width - 1);
}
}
}
dest.value(integer2binary(value, width));
}
else
{
ieee_floatt a;
a.spec = to_floatbv_type(dest.type());
if(base == 10)
a.from_base10(significand, exponent);
else if(base == 2) // hex
a.build(significand, exponent);
else
assert(false);
dest.value(integer2binary(a.pack(), a.spec.width()));
}
}