bool remove_function_pointerst::is_type_compatible(
bool return_value_used,
const code_typet &call_type,
const code_typet &function_type)
{
// we are willing to ignore anything that's returned
// if we call with 'void'
if(!return_value_used)
{
}
else if(type_eq(call_type.return_type(), empty_typet(), ns))
{
// ok
}
else
{
if(!arg_is_type_compatible(call_type.return_type(),
function_type.return_type()))
return false;
}
// let's look at the parameters
const code_typet::parameterst &call_parameters=call_type.parameters();
const code_typet::parameterst &function_parameters=function_type.parameters();
if(function_type.has_ellipsis() &&
function_parameters.empty())
{
// always ok
}
else if(call_type.has_ellipsis() &&
call_parameters.empty())
{
// always ok
}
else
{
// we are quite strict here, could be much more generous
if(call_parameters.size()!=function_parameters.size())
return false;
for(unsigned i=0; i<call_parameters.size(); i++)
if(!arg_is_type_compatible(call_parameters[i].type(),
function_parameters[i].type()))
return false;
}
return true;
}
void goto_inlinet::parameter_destruction(
const source_locationt &source_location,
const irep_idt &function_name,
const code_typet &code_type,
goto_programt &dest)
{
const code_typet::parameterst ¶meter_types=
code_type.parameters();
// iterates over the types of the parameters
for(code_typet::parameterst::const_iterator
it=parameter_types.begin();
it!=parameter_types.end();
it++)
{
const code_typet::parametert ¶meter=*it;
const irep_idt &identifier=parameter.get_identifier();
if(identifier==irep_idt())
{
error().source_location=source_location;
error() << "no identifier for function parameter" << eom;
throw 0;
}
{
const symbolt &symbol=ns.lookup(identifier);
goto_programt::targett dead=dest.add_instruction();
dead->make_dead();
dead->code=code_deadt(symbol.symbol_expr());
dead->code.add_source_location()=source_location;
dead->source_location=source_location;
dead->function=function_name;
}
}
}
void c_typecheck_baset::typecheck_code_type(code_typet &type)
{
// the return type is still 'subtype()'
type.return_type()=type.subtype();
type.remove_subtype();
code_typet::parameterst ¶meters=type.parameters();
// if we don't have any parameters, we assume it's (...)
if(parameters.empty())
{
type.make_ellipsis();
}
else // we do have parameters
{
// is the last one ellipsis?
if(type.parameters().back().id()==ID_ellipsis)
{
type.make_ellipsis();
type.parameters().pop_back();
}
parameter_map.clear();
for(auto ¶m : type.parameters())
{
// turn the declarations into parameters
if(param.id()==ID_declaration)
{
ansi_c_declarationt &declaration=
to_ansi_c_declaration(param);
code_typet::parametert parameter;
// first fix type
typet &type=parameter.type();
type=declaration.full_type(declaration.declarator());
std::list<codet> tmp_clean_code;
tmp_clean_code.swap(clean_code); // ignore side-effects
typecheck_type(type);
tmp_clean_code.swap(clean_code);
adjust_function_parameter(type);
// adjust the identifier
irep_idt identifier=declaration.declarator().get_name();
// abstract or not?
if(identifier==irep_idt())
{
// abstract
parameter.add_source_location()=declaration.type().source_location();
}
else
{
// make visible now, later parameters might use it
parameter_map[identifier]=type;
parameter.set_base_name(declaration.declarator().get_base_name());
parameter.add_source_location()=
declaration.declarator().source_location();
}
// put the parameter in place of the declaration
param.swap(parameter);
}
}
parameter_map.clear();
if(parameters.size()==1 &&
follow(parameters[0].type()).id()==ID_empty)
{
// if we just have one parameter of type void, remove it
parameters.clear();
}
}
typecheck_type(type.return_type());
// 6.7.6.3:
// "A function declarator shall not specify a return type that
// is a function type or an array type."
const typet &return_type=follow(type.return_type());
if(return_type.id()==ID_array)
{
error().source_location=type.source_location();
error() << "function must not return array" << eom;
throw 0;
}
if(return_type.id()==ID_code)
{
error().source_location=type.source_location();
error() << "function must not return function type" << eom;
throw 0;
}
}
void c_typecheck_baset::typecheck_code_type(code_typet &type)
{
code_typet::parameterst ¶meters=type.parameters();
// if we don't have any parameters, we assume it's (...)
if(parameters.empty())
{
type.make_ellipsis();
}
else
{
// we do have parameters
parameter_map.clear();
for(unsigned i=0; i<type.parameters().size(); i++)
{
code_typet::parametert ¶meter=type.parameters()[i];
// first fix type
typet &type=parameter.type();
typecheck_type(type);
adjust_function_parameter(type);
// adjust the identifier
irep_idt identifier=parameter.get_identifier();
if(identifier!=irep_idt())
{
identifier=add_language_prefix(identifier);
id_replace_mapt::const_iterator
m_it=id_replace_map.find(identifier);
if(m_it!=id_replace_map.end())
identifier=m_it->second;
parameter.set_identifier(identifier);
// make visible now, later parameters might use it
parameter_map[identifier]=type;
}
}
parameter_map.clear();
if(parameters.size()==1 &&
follow(parameters[0].type()).id()==ID_empty)
{
// if we just have one parameter of type void, remove it
parameters.clear();
}
}
typecheck_type(type.return_type());
// 6.7.6.3:
// "A function declarator shall not specify a return type that
// is a function type or an array type."
const typet &return_type=follow(type.return_type());
if(return_type.id()==ID_array)
{
err_location(type);
throw "function must not return array";
}
if(return_type.id()==ID_code)
{
err_location(type);
throw "function must not return function type";
}
}
void goto_inlinet::parameter_assignments(
const source_locationt &source_location,
const irep_idt &function_name,
const code_typet &code_type,
const exprt::operandst &arguments,
goto_programt &dest)
{
// iterates over the operands
exprt::operandst::const_iterator it1=arguments.begin();
const code_typet::parameterst ¶meter_types=
code_type.parameters();
// iterates over the types of the parameters
for(code_typet::parameterst::const_iterator
it2=parameter_types.begin();
it2!=parameter_types.end();
it2++)
{
const code_typet::parametert ¶meter=*it2;
// this is the type the n-th argument should be
const typet &par_type=ns.follow(parameter.type());
const irep_idt &identifier=parameter.get_identifier();
if(identifier==irep_idt())
{
error().source_location=source_location;
error() << "no identifier for function parameter" << eom;
throw 0;
}
{
const symbolt &symbol=ns.lookup(identifier);
goto_programt::targett decl=dest.add_instruction();
decl->make_decl();
decl->code=code_declt(symbol.symbol_expr());
decl->code.add_source_location()=source_location;
decl->source_location=source_location;
decl->function=function_name;
}
// this is the actual parameter
exprt actual;
// if you run out of actual arguments there was a mismatch
if(it1==arguments.end())
{
warning().source_location=source_location;
warning() << "call to `" << function_name << "': "
<< "not enough arguments, "
<< "inserting non-deterministic value" << eom;
actual=side_effect_expr_nondett(par_type);
}
else
actual=*it1;
// nil means "don't assign"
if(actual.is_nil())
{
}
else
{
// it should be the same exact type as the parameter,
// subject to some exceptions
if(!base_type_eq(par_type, actual.type(), ns))
{
const typet &f_partype = ns.follow(par_type);
const typet &f_acttype = ns.follow(actual.type());
// we are willing to do some conversion
if((f_partype.id()==ID_pointer &&
f_acttype.id()==ID_pointer) ||
(f_partype.id()==ID_pointer &&
f_acttype.id()==ID_array &&
f_partype.subtype()==f_acttype.subtype()))
{
actual.make_typecast(par_type);
}
else if((f_partype.id()==ID_signedbv ||
f_partype.id()==ID_unsignedbv ||
f_partype.id()==ID_bool) &&
(f_acttype.id()==ID_signedbv ||
f_acttype.id()==ID_unsignedbv ||
f_acttype.id()==ID_bool))
{
actual.make_typecast(par_type);
}
else
{
error().source_location=actual.find_source_location();
error() << "function call: argument `" << identifier
<< "' type mismatch: argument is `"
// << from_type(ns, identifier, actual.type())
<< actual.type().pretty()
<< "', parameter is `"
<< from_type(ns, identifier, par_type)
<< "'" << eom;
throw 0;
}
}
// adds an assignment of the actual parameter to the formal parameter
code_assignt assignment(symbol_exprt(identifier, par_type), actual);
assignment.add_source_location()=source_location;
dest.add_instruction(ASSIGN);
dest.instructions.back().source_location=source_location;
dest.instructions.back().code.swap(assignment);
dest.instructions.back().function=function_name;
}
if(it1!=arguments.end())
++it1;
}
if(it1!=arguments.end())
{
// too many arguments -- we just ignore that, no harm done
}
}
bool cpp_typecheck_fargst::match(
const code_typet &code_type,
unsigned &distance,
cpp_typecheckt &cpp_typecheck) const
{
distance=0;
exprt::operandst ops = operands;
const code_typet::parameterst ¶meters=code_type.parameters();
if(parameters.size()>ops.size())
{
// Check for default values.
ops.reserve(parameters.size());
for(std::size_t i=ops.size(); i<parameters.size(); i++)
{
const exprt &default_value=
parameters[i].default_value();
if(default_value.is_nil())
return false;
ops.push_back(default_value);
}
}
else if(parameters.size()<ops.size())
{
// check for ellipsis
if(!code_type.has_ellipsis())
return false;
}
for(std::size_t i=0; i<ops.size(); i++)
{
// read
// http://publib.boulder.ibm.com/infocenter/comphelp/v8v101/topic/com.ibm.xlcpp8a.doc/language/ref/implicit_conversion_sequences.htm
//
// The following are the three categories of conversion sequences in order from best to worst:
// * Standard conversion sequences
// * User-defined conversion sequences
// * Ellipsis conversion sequences
if(i>=parameters.size())
{
// Ellipsis is the 'worst' of the conversion sequences
distance+=1000;
continue;
}
exprt parameter=parameters[i];
exprt &operand=ops[i];
#if 0
// unclear, todo
if(is_reference(operand.type()))
std::cout << "O: " << operand.pretty() << std::endl;
assert(!is_reference(operand.type()));
#endif
// "this" is a special case -- we turn the pointer type
// into a reference type to do the type matching
if(i==0 && parameter.get(ID_C_base_name)==ID_this)
{
parameter.type().set(ID_C_reference, true);
parameter.type().set("#this", true);
}
unsigned rank = 0;
exprt new_expr;
#if 0
std::cout << "C: " << cpp_typecheck.to_string(operand.type())
<< " -> " << cpp_typecheck.to_string(parameter.type()) << std::endl;
#endif
// can we do the standard conversion sequence?
if(cpp_typecheck.implicit_conversion_sequence(
operand, parameter.type(), new_expr, rank))
{
// ok
distance+=rank;
#if 0
std::cout << "OK " << rank << std::endl;
#endif
}
else
{
#if 0
std::cout << "NOT OK" << std::endl;
#endif
return false; // no conversion possible
}
}
return true;
}