void goto_convertt::convert_msc_leave(
const codet &code,
goto_programt &dest)
{
if(!targets.leave_set)
{
error().source_location=code.find_source_location();
error() << "leave without target" << eom;
throw 0;
}
// need to process destructor stack
for(unsigned d=targets.destructor_stack.size();
d!=targets.leave_stack_size;
d--)
{
codet d_code=targets.destructor_stack[d-1];
d_code.add_source_location()=code.source_location();
convert(d_code, dest);
}
goto_programt::targett t=dest.add_instruction();
t->make_goto(targets.leave_target);
t->source_location=code.source_location();
}
void goto_convertt::convert_CPROVER_throw(
const codet &code,
goto_programt &dest)
{
// set the 'exception' flag
{
goto_programt::targett t_set_exception=
dest.add_instruction(ASSIGN);
t_set_exception->source_location=code.source_location();
t_set_exception->code=code_assignt(exception_flag(), true_exprt());
}
// do we catch locally?
if(targets.throw_set)
{
// need to process destructor stack
unwind_destructor_stack(code.source_location(), targets.throw_stack_size, dest);
// add goto
goto_programt::targett t=dest.add_instruction();
t->make_goto(targets.throw_target);
t->source_location=code.source_location();
}
else // otherwise, we do a return
{
// need to process destructor stack
unwind_destructor_stack(code.source_location(), 0, dest);
// add goto
goto_programt::targett t=dest.add_instruction();
t->make_goto(targets.return_target);
t->source_location=code.source_location();
}
}
void goto_convertt::convert_CPROVER_try_catch(
const codet &code,
goto_programt &dest)
{
if(code.operands().size()!=2)
{
err_location(code);
throw "CPROVER_try_catch expects two arguments";
}
// this is where we go after 'throw'
goto_programt tmp;
tmp.add_instruction(SKIP)->source_location=code.source_location();
// set 'throw' target
throw_targett throw_target(targets);
targets.set_throw(tmp.instructions.begin());
// now put 'catch' code onto destructor stack
code_ifthenelset catch_code;
catch_code.cond()=exception_flag();
catch_code.add_source_location()=code.source_location();
catch_code.then_case()=to_code(code.op1());
targets.destructor_stack.push_back(catch_code);
// now convert 'try' code
convert(to_code(code.op0()), dest);
// pop 'catch' code off stack
targets.destructor_stack.pop_back();
// add 'throw' target
dest.destructive_append(tmp);
}
void goto_convertt::convert_java_try_catch(
const codet &code,
goto_programt &dest)
{
assert(!code.operands().empty());
// add the CATCH instruction to 'dest'
goto_programt::targett catch_instruction=dest.add_instruction();
catch_instruction->make_catch();
catch_instruction->code.set_statement(ID_catch);
catch_instruction->source_location=code.source_location();
catch_instruction->function=code.source_location().get_function();
// the CATCH instruction is annotated with a list of exception IDs
const irept exceptions=code.op0().find(ID_exception_list);
if(exceptions.is_not_nil())
{
irept::subt exceptions_sub=exceptions.get_sub();
irept::subt &exception_list=
catch_instruction->code.add(ID_exception_list).get_sub();
exception_list.resize(exceptions_sub.size());
for(size_t i=0; i<exceptions_sub.size(); ++i)
exception_list[i].id(exceptions_sub[i].id());
}
// the CATCH instruction is also annotated with a list of handle labels
const irept handlers=code.op0().find(ID_label);
if(handlers.is_not_nil())
{
irept::subt handlers_sub=handlers.get_sub();
irept::subt &handlers_list=
catch_instruction->code.add(ID_label).get_sub();
handlers_list.resize(handlers_sub.size());
for(size_t i=0; i<handlers_sub.size(); ++i)
handlers_list[i].id(handlers_sub[i].id());
}
// the CATCH instruction may also signal a handler
if(code.op0().has_operands())
{
catch_instruction->code.get_sub().resize(1);
catch_instruction->code.get_sub()[0]=code.op0().op0();
}
// add a SKIP target for the end of everything
goto_programt end;
goto_programt::targett end_target=end.add_instruction();
end_target->make_skip();
end_target->source_location=code.source_location();
end_target->function=code.source_location().get_function();
// add the end-target
dest.destructive_append(end);
}
void c_typecheck_baset::typecheck_return(codet &code)
{
if(code.operands().empty())
{
if(follow(return_type).id()!=ID_empty)
{
// gcc doesn't actually complain, it just warns!
// We'll put a zero here, which is dubious.
exprt zero=zero_initializer(return_type, code.source_location(), *this, get_message_handler());
code.copy_to_operands(zero);
}
}
else if(code.operands().size()==1)
{
typecheck_expr(code.op0());
if(follow(return_type).id()==ID_empty)
{
// gcc doesn't actually complain, it just warns!
if(follow(code.op0().type()).id()!=ID_empty)
{
warning().source_location=code.source_location();
warning() << "function has return void ";
warning() << "but a return statement returning ";
warning() << to_string(follow(code.op0().type()));
warning() << eom;
code.op0().make_typecast(return_type);
}
}
else
implicit_typecast(code.op0(), return_type);
}
else
{
err_location(code);
error() << "return expected to have 0 or 1 operands" << eom;
throw 0;
}
}
void goto_convertt::convert_try_catch(
const codet &code,
goto_programt &dest)
{
assert(code.operands().size()>=2);
// add the CATCH-push instruction to 'dest'
goto_programt::targett catch_push_instruction=dest.add_instruction();
catch_push_instruction->make_catch();
catch_push_instruction->code.set_statement(ID_catch);
catch_push_instruction->source_location=code.source_location();
// the CATCH-push instruction is annotated with a list of IDs,
// one per target
irept::subt &exception_list=
catch_push_instruction->code.add(ID_exception_list).get_sub();
// add a SKIP target for the end of everything
goto_programt end;
goto_programt::targett end_target=end.add_instruction();
end_target->make_skip();
// the first operand is the 'try' block
convert(to_code(code.op0()), dest);
// add the CATCH-pop to the end of the 'try' block
goto_programt::targett catch_pop_instruction=dest.add_instruction();
catch_pop_instruction->make_catch();
catch_pop_instruction->code.set_statement(ID_catch);
// add a goto to the end of the 'try' block
dest.add_instruction()->make_goto(end_target);
for(unsigned i=1; i<code.operands().size(); i++)
{
const codet &block=to_code(code.operands()[i]);
// grab the ID and add to CATCH instruction
exception_list.push_back(irept(block.get(ID_exception_id)));
goto_programt tmp;
convert(block, tmp);
catch_push_instruction->targets.push_back(tmp.instructions.begin());
dest.destructive_append(tmp);
// add a goto to the end of the 'catch' block
dest.add_instruction()->make_goto(end_target);
}
// add the end-target
dest.destructive_append(end);
}
void goto_convertt::convert_msc_try_finally(
const codet &code,
goto_programt &dest)
{
if(code.operands().size()!=2)
{
error().source_location=code.find_source_location();
error() << "msc_try_finally expects two arguments" << eom;
throw 0;
}
goto_programt tmp;
tmp.add_instruction(SKIP)->source_location=code.source_location();
{
// save 'leave' target
leave_targett leave_target(targets);
targets.set_leave(tmp.instructions.begin());
// first put 'finally' code onto destructor stack
targets.destructor_stack.push_back(to_code(code.op1()));
// do 'try' code
convert(to_code(code.op0()), dest);
// pop 'finally' from destructor stack
targets.destructor_stack.pop_back();
// 'leave' target gets restored here
}
// now add 'finally' code
convert(to_code(code.op1()), dest);
// this is the target for 'leave'
dest.destructive_append(tmp);
}
void c_typecheck_baset::typecheck_for(codet &code)
{
if(code.operands().size()!=4)
{
err_location(code);
error() << "for expected to have four operands" << eom;
throw 0;
}
// the "for" statement has an implicit block around it,
// since code.op0() may contain declarations
//
// we therefore transform
//
// for(a;b;c) d;
//
// to
//
// { a; for(;b;c) d; }
//
// if config.ansi_c.for_has_scope
if(!config.ansi_c.for_has_scope ||
code.op0().is_nil())
{
if(code.op0().is_not_nil())
typecheck_code(to_code(code.op0()));
if(code.op1().is_nil())
code.op1()=true_exprt();
else
{
typecheck_expr(code.op1());
implicit_typecast_bool(code.op1());
}
if(code.op2().is_not_nil())
typecheck_expr(code.op2());
if(code.op3().is_not_nil())
{
// save & set flags
bool old_break_is_allowed=break_is_allowed;
bool old_continue_is_allowed=continue_is_allowed;
break_is_allowed=continue_is_allowed=true;
// recursive call
if(to_code(code.op3()).get_statement()==ID_decl_block)
{
code_blockt code_block;
code_block.add_source_location()=code.op3().source_location();
code_block.move_to_operands(code.op3());
code.op3().swap(code_block);
}
typecheck_code(to_code(code.op3()));
// restore flags
break_is_allowed=old_break_is_allowed;
continue_is_allowed=old_continue_is_allowed;
}
}
else
{
code_blockt code_block;
code_block.add_source_location()=code.source_location();
if(to_code(code.op3()).get_statement()==ID_block)
code_block.set(
ID_C_end_location,
to_code_block(to_code(code.op3())).end_location());
else
code_block.set(
ID_C_end_location,
code.op3().source_location());;
code_block.reserve_operands(2);
code_block.move_to_operands(code.op0());
code.op0().make_nil();
code_block.move_to_operands(code);
code.swap(code_block);
typecheck_code(code); // recursive call
}
typecheck_spec_expr(code, ID_C_spec_loop_invariant);
}
void c_typecheck_baset::typecheck_decl(codet &code)
{
// this comes with 1 operand, which is a declaration
if(code.operands().size()!=1)
{
err_location(code);
error() << "decl expected to have 1 operand" << eom;
throw 0;
}
// op0 must be declaration
if(code.op0().id()!=ID_declaration)
{
err_location(code);
error() << "decl statement expected to have declaration as operand"
<< eom;
throw 0;
}
ansi_c_declarationt declaration;
declaration.swap(code.op0());
if(declaration.get_is_static_assert())
{
assert(declaration.operands().size()==2);
codet new_code(ID_static_assert);
new_code.add_source_location()=code.source_location();
new_code.operands().swap(declaration.operands());
code.swap(new_code);
typecheck_code(code);
return; // done
}
typecheck_declaration(declaration);
std::list<codet> new_code;
// iterate over declarators
for(ansi_c_declarationt::declaratorst::const_iterator
d_it=declaration.declarators().begin();
d_it!=declaration.declarators().end();
d_it++)
{
irep_idt identifier=d_it->get_name();
// look it up
symbol_tablet::symbolst::iterator s_it=
symbol_table.symbols.find(identifier);
if(s_it==symbol_table.symbols.end())
{
err_location(code);
error() << "failed to find decl symbol `" << identifier
<< "' in symbol table" << eom;
throw 0;
}
symbolt &symbol=s_it->second;
// This must not be an incomplete type, unless it's 'extern'
// or a typedef.
if(!symbol.is_type &&
!symbol.is_extern &&
!is_complete_type(symbol.type))
{
error().source_location=symbol.location;
error() << "incomplete type not permitted here" << eom;
throw 0;
}
// see if it's a typedef
// or a function
// or static
if(symbol.is_type ||
symbol.type.id()==ID_code ||
symbol.is_static_lifetime)
{
// we ignore
}
else
{
code_declt code;
code.add_source_location()=symbol.location;
code.symbol()=symbol.symbol_expr();
code.symbol().add_source_location()=symbol.location;
// add initializer, if any
if(symbol.value.is_not_nil())
{
code.operands().resize(2);
code.op1()=symbol.value;
}
new_code.push_back(code);
}
}
// stash away any side-effects in the declaration
new_code.splice(new_code.begin(), clean_code);
if(new_code.empty())
{
source_locationt source_location=code.source_location();
code=code_skipt();
code.add_source_location()=source_location;
}
else if(new_code.size()==1)
{
code.swap(new_code.front());
}
else
{
// build a decl-block
code_blockt code_block(new_code);
code_block.set_statement(ID_decl_block);
code.swap(code_block);
}
}