String *ParmList_protostr(ParmList *p) {
String *out = NewStringEmpty();
while (p) {
String *type = Getattr(p, "type");
String *pstr = SwigType_str(type ? type : get_empty_type(), 0);
Append(out, pstr);
p = nextSibling(p);
if (p) {
Append(out, ",");
}
Delete(pstr);
}
return out;
}
String *ParmList_str_defaultargs(ParmList *p) {
String *out = NewStringEmpty();
while (p) {
String *value = Getattr(p, "value");
String *type = Getattr(p, "type");
String *pstr = SwigType_str(type ? type : get_empty_type(), Getattr(p, "name"));
Append(out, pstr);
if (value) {
Printf(out, "=%s", value);
}
p = nextSibling(p);
if (p) {
Append(out, ",");
}
Delete(pstr);
}
return out;
}
expr2tc
goto_symext::symex_mem(
const bool is_malloc,
const expr2tc &lhs,
const sideeffect2t &code)
{
if (is_nil_expr(lhs))
return expr2tc(); // ignore
// size
type2tc type = code.alloctype;
expr2tc size = code.size;
bool size_is_one = false;
if (is_nil_expr(size))
size_is_one=true;
else
{
cur_state->rename(size);
mp_integer i;
if (is_constant_int2t(size) && to_constant_int2t(size).as_ulong() == 1)
size_is_one = true;
}
if (is_nil_type(type))
type = char_type2();
else if (is_union_type(type)) {
// Filter out creation of instantiated unions. They're now all byte arrays.
size_is_one = false;
type = char_type2();
}
unsigned int &dynamic_counter = get_dynamic_counter();
dynamic_counter++;
// value
symbolt symbol;
symbol.base_name = "dynamic_" + i2string(dynamic_counter) +
(size_is_one ? "_value" : "_array");
symbol.name = "symex_dynamic::" + id2string(symbol.base_name);
symbol.lvalue = true;
typet renamedtype = ns.follow(migrate_type_back(type));
if(size_is_one)
symbol.type=renamedtype;
else
{
symbol.type=typet(typet::t_array);
symbol.type.subtype()=renamedtype;
symbol.type.size(migrate_expr_back(size));
}
symbol.type.dynamic(true);
symbol.mode="C";
new_context.add(symbol);
type2tc new_type;
migrate_type(symbol.type, new_type);
address_of2tc rhs_addrof(get_empty_type(), expr2tc());
if(size_is_one)
{
rhs_addrof.get()->type = get_pointer_type(pointer_typet(symbol.type));
rhs_addrof.get()->ptr_obj = symbol2tc(new_type, symbol.name);
}
else
{
type2tc subtype;
migrate_type(symbol.type.subtype(), subtype);
expr2tc sym = symbol2tc(new_type, symbol.name);
expr2tc idx_val = zero_ulong;
expr2tc idx = index2tc(subtype, sym, idx_val);
rhs_addrof.get()->type =
get_pointer_type(pointer_typet(symbol.type.subtype()));
rhs_addrof.get()->ptr_obj = idx;
}
expr2tc rhs = rhs_addrof;
expr2tc ptr_rhs = rhs;
if (!options.get_bool_option("force-malloc-success")) {
symbol2tc null_sym(rhs->type, "NULL");
sideeffect2tc choice(get_bool_type(), expr2tc(), expr2tc(), std::vector<expr2tc>(), type2tc(), sideeffect2t::nondet);
rhs = if2tc(rhs->type, choice, rhs, null_sym);
replace_nondet(rhs);
ptr_rhs = rhs;
}
if (rhs->type != lhs->type)
rhs = typecast2tc(lhs->type, rhs);
cur_state->rename(rhs);
expr2tc rhs_copy(rhs);
guardt guard;
symex_assign_rec(lhs, rhs, guard);
pointer_object2tc ptr_obj(pointer_type2(), ptr_rhs);
track_new_pointer(ptr_obj, new_type);
dynamic_memory.push_back(allocated_obj(rhs_copy, cur_state->guard, !is_malloc));
return rhs_addrof->ptr_obj;
}
void goto_symext::symex_realloc(const expr2tc &lhs, const sideeffect2t &code)
{
expr2tc src_ptr = code.operand;
expr2tc realloc_size = code.size;
internal_deref_items.clear();
dereference2tc deref(get_empty_type(), src_ptr);
dereference(deref, dereferencet::INTERNAL);
// src_ptr is now invalidated.
// Free the given pointer. This just uses the pointer object from the pointer
// variable that's the argument to realloc. It also leads to pointer validity
// checking, and checks that the offset is zero.
code_free2tc fr(code.operand);
symex_free(fr);
// We now have a list of things to work on. Recurse into them, build a result,
// and then switch between those results afterwards.
// Result list is the address of the reallocated piece of data, and the guard.
std::list<std::pair<expr2tc, expr2tc>> result_list;
for(auto &item : internal_deref_items)
{
expr2tc guard = item.guard;
cur_state->rename_address(item.object);
cur_state->guard.guard_expr(guard);
target->renumber(guard, item.object, realloc_size, cur_state->source);
type2tc new_ptr = type2tc(new pointer_type2t(item.object->type));
address_of2tc addrof(new_ptr, item.object);
result_list.emplace_back(addrof, item.guard);
// Bump the realloc-numbering of the object. This ensures that, after
// renaming, the address_of we just generated compares differently to
// previous address_of's before the realloc.
unsigned int cur_num = 0;
if(cur_state->realloc_map.find(item.object) != cur_state->realloc_map.end())
{
cur_num = cur_state->realloc_map[item.object];
}
cur_num++;
std::map<expr2tc, unsigned>::value_type v(item.object, cur_num);
cur_state->realloc_map.insert(v);
}
// Rebuild a gigantic if-then-else chain from the result list.
expr2tc result;
if(result_list.size() == 0)
{
// Nothing happened; there was nothing, or only null, to point at.
// In this case, just return right now and leave the pointer free. The
// symex_free that occurred above should trigger a dereference failure.
return;
}
result = expr2tc();
for(auto const &it : result_list)
{
if(is_nil_expr(result))
result = it.first;
else
result = if2tc(result->type, it.second, it.first, result);
}
// Install pointer modelling data into the relevant arrays.
pointer_object2tc ptr_obj(pointer_type2(), result);
track_new_pointer(ptr_obj, type2tc(), realloc_size);
symex_assign(code_assign2tc(lhs, result), true);
}
void goto_symext::symex_other()
{
const goto_programt::instructiont &instruction = *cur_state->source.pc;
expr2tc code2 = instruction.code;
if(is_code_expression2t(code2))
{
// Represents an expression that gets evaluated, but does not have any
// other effect on execution, i.e. doesn't contain a call or assignment.
// This can, however, cause the program to fail if it dereferences an
// invalid pointer. Therefore, dereference it.
const code_expression2t &expr = to_code_expression2t(code2);
expr2tc operand = expr.operand;
dereference(operand, dereferencet::READ);
}
else if(is_code_cpp_del_array2t(code2) || is_code_cpp_delete2t(code2))
{
expr2tc deref_code(code2);
replace_dynamic_allocation(deref_code);
replace_nondet(deref_code);
dereference(deref_code, dereferencet::READ);
symex_cpp_delete(deref_code);
}
else if(is_code_free2t(code2))
{
symex_free(code2);
}
else if(is_code_printf2t(code2))
{
replace_dynamic_allocation(code2);
replace_nondet(code2);
dereference(code2, dereferencet::READ);
symex_printf(expr2tc(), code2);
}
else if(is_code_decl2t(code2))
{
replace_dynamic_allocation(code2);
replace_nondet(code2);
dereference(code2, dereferencet::READ);
const code_decl2t &decl_code = to_code_decl2t(code2);
// just do the L2 renaming to preseve locality
const irep_idt &identifier = decl_code.value;
// Generate dummy symbol as a vehicle for renaming.
symbol2tc l1_sym(get_empty_type(), identifier);
cur_state->top().level1.get_ident_name(l1_sym);
symbol2t &l1_symbol = to_symbol2t(l1_sym);
// increase the frame if we have seen this declaration before
while(cur_state->top().declaration_history.find(
renaming::level2t::name_record(l1_symbol)) !=
cur_state->top().declaration_history.end())
{
unsigned &index = cur_state->variable_instance_nums[identifier];
cur_state->top().level1.rename(l1_sym, ++index);
l1_symbol.level1_num = index;
}
renaming::level2t::name_record tmp_name(l1_symbol);
cur_state->top().declaration_history.insert(tmp_name);
cur_state->top().local_variables.insert(tmp_name);
// seen it before?
// it should get a fresh value
if(cur_state->level2.current_number(l1_sym) != 0)
{
// Dummy assignment - blank constant value isn't considered for const
// propagation, variable number will be bumped to result in a new free
// variable. Invalidates l1_symbol reference?
cur_state->level2.make_assignment(l1_sym, expr2tc(), expr2tc());
}
}
else if(is_code_asm2t(code2))
{
// Assembly statement -> do nothing.
return;
}
else
throw "goto_symext: unexpected statement: " + get_expr_id(code2);
}
