void c_typecheck_baset::typecheck_switch(code_switcht &code)
{
if(code.operands().size()!=2)
{
err_location(code);
error() << "switch expects two operands" << eom;
throw 0;
}
typecheck_expr(code.value());
// this needs to be promoted
implicit_typecast_arithmetic(code.value());
// save & set flags
bool old_case_is_allowed(case_is_allowed);
bool old_break_is_allowed(break_is_allowed);
typet old_switch_op_type(switch_op_type);
switch_op_type=code.value().type();
break_is_allowed=case_is_allowed=true;
typecheck_code(code.body());
// restore flags
case_is_allowed=old_case_is_allowed;
break_is_allowed=old_break_is_allowed;
switch_op_type=old_switch_op_type;
}
void c_typecastt::implicit_typecast_arithmetic(
exprt &expr1,
exprt &expr2)
{
const typet &type1=ns.follow(expr1.type());
const typet &type2=ns.follow(expr2.type());
c_typet c_type1=get_c_type(type1),
c_type2=get_c_type(type2);
c_typet max_type=std::max(c_type1, c_type2);
// "If an int can represent all values of the original type, the
// value is converted to an int; otherwise, it is converted to
// an unsigned int."
// The second case can arise if we promote any unsigned type
// that is as large as unsigned int.
if(config.ansi_c.short_int_width==config.ansi_c.int_width &&
max_type==USHORT)
max_type=UINT;
else if(config.ansi_c.char_width==config.ansi_c.int_width &&
max_type==UCHAR)
max_type=UINT;
else
max_type=std::max(max_type, INT);
if(max_type==LARGE_SIGNED_INT || max_type==LARGE_UNSIGNED_INT)
{
// get the biggest width of both
unsigned width1=type1.get_int(ID_width);
unsigned width2=type2.get_int(ID_width);
// produce type
typet result_type;
if(width1==width2)
{
if(max_type==LARGE_SIGNED_INT)
result_type=signedbv_typet(width1);
else
result_type=unsignedbv_typet(width1);
}
else if(width1>width2)
result_type=type1;
else // width1<width2
result_type=type2;
do_typecast(expr1, result_type);
do_typecast(expr2, result_type);
return;
}
else if(max_type==COMPLEX)
{
if(c_type1==COMPLEX && c_type2==COMPLEX)
{
// promote to the one with bigger subtype
if(get_c_type(type1.subtype())>get_c_type(type2.subtype()))
do_typecast(expr2, type1);
else
do_typecast(expr1, type2);
}
else if(c_type1==COMPLEX)
{
assert(c_type1==COMPLEX && c_type2!=COMPLEX);
do_typecast(expr2, type1.subtype());
do_typecast(expr2, type1);
}
else
{
assert(c_type1!=COMPLEX && c_type2==COMPLEX);
do_typecast(expr1, type2.subtype());
do_typecast(expr1, type2);
}
return;
}
implicit_typecast_arithmetic(expr1, max_type);
implicit_typecast_arithmetic(expr2, max_type);
if(max_type==PTR)
{
if(c_type1==VOIDPTR)
do_typecast(expr1, expr2.type());
if(c_type2==VOIDPTR)
do_typecast(expr2, expr1.type());
}
}
void c_typecastt::implicit_typecast_arithmetic(exprt &expr)
{
c_typet c_type=get_c_type(expr.type());
c_type=std::max(c_type, INT); // minimum promotion
implicit_typecast_arithmetic(expr, c_type);
}
void c_typecastt::implicit_typecast_arithmetic(
exprt &expr1,
exprt &expr2)
{
const typet &type1=ns.follow(expr1.type());
const typet &type2=ns.follow(expr2.type());
c_typet c_type1=minimum_promotion(type1),
c_type2=minimum_promotion(type2);
c_typet max_type=std::max(c_type1, c_type2);
if(max_type==LARGE_SIGNED_INT || max_type==LARGE_UNSIGNED_INT)
{
// get the biggest width of both
unsigned width1=type1.get_int(ID_width);
unsigned width2=type2.get_int(ID_width);
// produce type
typet result_type;
if(width1==width2)
{
if(max_type==LARGE_SIGNED_INT)
result_type=signedbv_typet(width1);
else
result_type=unsignedbv_typet(width1);
}
else if(width1>width2)
result_type=type1;
else // width1<width2
result_type=type2;
do_typecast(expr1, result_type);
do_typecast(expr2, result_type);
return;
}
else if(max_type==COMPLEX)
{
if(c_type1==COMPLEX && c_type2==COMPLEX)
{
// promote to the one with bigger subtype
if(get_c_type(type1.subtype())>get_c_type(type2.subtype()))
do_typecast(expr2, type1);
else
do_typecast(expr1, type2);
}
else if(c_type1==COMPLEX)
{
assert(c_type1==COMPLEX && c_type2!=COMPLEX);
do_typecast(expr2, type1.subtype());
do_typecast(expr2, type1);
}
else
{
assert(c_type1!=COMPLEX && c_type2==COMPLEX);
do_typecast(expr1, type2.subtype());
do_typecast(expr1, type2);
}
return;
}
else if(max_type==SINGLE || max_type==DOUBLE ||
max_type==LONGDOUBLE || max_type==FLOAT128)
{
// Special-case optimisation:
// If we have two non-standard sized floats, don't do implicit type
// promotion if we can possibly avoid it.
if(type1==type2)
return;
}
implicit_typecast_arithmetic(expr1, max_type);
implicit_typecast_arithmetic(expr2, max_type);
if(max_type==PTR)
{
if(c_type1==VOIDPTR)
do_typecast(expr1, expr2.type());
if(c_type2==VOIDPTR)
do_typecast(expr2, expr1.type());
}
}
void c_typecastt::implicit_typecast_arithmetic(exprt &expr)
{
c_typet c_type=minimum_promotion(expr.type());
implicit_typecast_arithmetic(expr, c_type);
}
