bool clang_c_convertert::convert_integer_literal(
  const clang::IntegerLiteral &integer_literal,
  exprt &dest)
{
  typet type;
  if(get_type(integer_literal.getType(), type))
    return true;

  assert(type.is_unsignedbv() || type.is_signedbv());

  llvm::APInt val = integer_literal.getValue();

  exprt the_val;
  if (type.is_unsignedbv())
  {
    the_val =
      constant_exprt(
        integer2binary(val.getZExtValue(), bv_width(type)),
        integer2string(val.getZExtValue()),
        type);
  }
  else
  {
    the_val =
      constant_exprt(
        integer2binary(val.getSExtValue(), bv_width(type)),
        integer2string(val.getSExtValue()),
        type);
  }

  dest.swap(the_val);
  return false;
}
Example #2
0
void thread_exit_instrumentation(goto_programt &goto_program)
{
  if(goto_program.instructions.empty()) return;

  // add assertion that all may flags for mutex-locked are gone
  // at the end
  goto_programt::targett end=goto_program.instructions.end();
  end--;

  assert(end->is_end_function());

  source_locationt source_location=end->source_location;
  irep_idt function=end->function;

  goto_program.insert_before_swap(end);

  exprt mutex_locked_string=
    string_constantt("mutex-locked");

  binary_exprt get_may("get_may");

  // NULL is any
  get_may.op0()=constant_exprt(ID_NULL, pointer_typet(empty_typet()));
  get_may.op1()=address_of_exprt(mutex_locked_string);

  end->make_assertion(not_exprt(get_may));

  end->source_location=source_location;
  end->source_location.set_comment("mutexes must not be locked on thread exit");
  end->function=function;
}
Example #3
0
exprt gen_one(const typet &type)
{
  const irep_idt type_id=type.id();
  exprt result=constant_exprt(type);

  if(type_id==ID_bool ||
     type_id==ID_rational ||
     type_id==ID_real ||
     type_id==ID_integer ||
     type_id==ID_natural)
  {
    result.set(ID_value, ID_1);
  }
  else if(type_id==ID_unsignedbv ||
          type_id==ID_signedbv ||
          type_id==ID_c_enum)
  {
    std::string value;
    unsigned width=to_bitvector_type(type).get_width();
    for(unsigned i=0; i<width-1; i++)
      value+='0';
    value+='1';
    result.set(ID_value, value);
  }
  else if(type_id==ID_fixedbv)
  {
    fixedbvt fixedbv;
    fixedbv.spec=to_fixedbv_type(type);
    fixedbv.from_integer(1);
    result=fixedbv.to_expr();
  }
  else if(type_id==ID_floatbv)
  {
    ieee_floatt ieee_float;
    ieee_float.spec=to_floatbv_type(type);
    ieee_float.from_integer(1);
    result=ieee_float.to_expr();
  }
  else if(type_id==ID_complex)
  {
    result=exprt(ID_complex, type);
    result.operands().resize(2);
    result.op0()=gen_one(type.subtype());
    result.op1()=gen_zero(type.subtype());
  }
  else
    result.make_nil();

  return result;
}
Example #4
0
exprt gen_zero(const typet &type)
{
  exprt result;

  const irep_idt type_id=type.id();

  result=constant_exprt(type);

  if(type_id==ID_rational ||
     type_id==ID_real ||
     type_id==ID_integer ||
     type_id==ID_natural ||
     type_id==ID_complex ||
     type_id==ID_c_enum)
  {
    result.set(ID_value, ID_0);
  }
  else if(type_id==ID_unsignedbv ||
          type_id==ID_signedbv ||
          type_id==ID_verilogbv ||
          type_id==ID_floatbv ||
          type_id==ID_fixedbv)
  {
    std::string value;
    unsigned width=to_bitvector_type(type).get_width();

    for(unsigned i=0; i<width; i++)
      value+='0';

    result.set(ID_value, value);
  }
  else if(type_id==ID_complex)
  {
    result=exprt(ID_complex, type);
    exprt sub_zero=gen_zero(type.subtype());
    result.operands().resize(2, sub_zero);
  }
  else if(type_id==ID_bool)
  {
    result.make_false();
  }
  else if(type_id==ID_pointer)
  {
    result.set(ID_value, ID_NULL);
  }
  else
    result.make_nil();

  return result;
}
bool clang_c_convertert::convert_character_literal(
  const clang::CharacterLiteral &char_literal,
  exprt &dest)
{
  typet type;
  if(get_type(char_literal.getType(), type))
    return true;

  dest =
    constant_exprt(
      integer2binary(char_literal.getValue(), bv_width(type)),
      integer2string(char_literal.getValue()),
      type);

  return false;
}
void set_class_identifier(
  struct_exprt &expr,
  const namespacet &ns,
  const symbol_typet &class_type)
{
  const struct_typet &struct_type=
    to_struct_type(ns.follow(expr.type()));
  const struct_typet::componentst &components=struct_type.components();

  if(components.empty()) return;
  assert(!expr.operands().empty());
  
  if(components.front().get_name()=="@class_identifier")
  {
    assert(expr.op0().id()==ID_constant);
    expr.op0()=constant_exprt(class_type.get_identifier(), string_typet());
  }
  else
  {
    assert(expr.op0().id()==ID_struct);
    set_class_identifier(to_struct_expr(expr.op0()), ns, class_type);
  }
}
void remove_virtual_functionst::remove_virtual_function(
  goto_programt &goto_program,
  goto_programt::targett target)
{
  const code_function_callt &code=
    to_code_function_call(target->code);

  const auto &vcall_source_loc=target->source_location;

  const exprt &function=code.function();
  assert(function.id()==ID_virtual_function);
  assert(!code.arguments().empty());

  functionst functions;
  get_functions(function, functions);

  if(functions.empty())
  {
    target->make_skip();
    return; // give up
  }

  // only one option?
  if(functions.size()==1)
  {
    assert(target->is_function_call());
    if(functions.begin()->symbol_expr==symbol_exprt())
      target->make_skip();
    else
      to_code_function_call(target->code).function()=
        functions.begin()->symbol_expr;
    return;
  }

  // the final target is a skip
  goto_programt final_skip;

  goto_programt::targett t_final=final_skip.add_instruction();
  t_final->source_location=vcall_source_loc;

  t_final->make_skip();

  // build the calls and gotos

  goto_programt new_code_calls;
  goto_programt new_code_gotos;

  exprt this_expr=code.arguments()[0];
  // If necessary, cast to the last candidate function to
  // get the object's clsid. By the structure of get_functions,
  // this is the parent of all other classes under consideration.
  const auto &base_classid=functions.back().class_id;
  const auto &base_function_symbol=functions.back().symbol_expr;
  symbol_typet suggested_type(base_classid);
  exprt c_id2=get_class_identifier_field(this_expr, suggested_type, ns);

  std::map<irep_idt, goto_programt::targett> calls;
  // Note backwards iteration, to get the least-derived candidate first.
  for(auto it=functions.crbegin(), itend=functions.crend(); it!=itend; ++it)
  {
    const auto &fun=*it;
    auto insertit=calls.insert(
      {fun.symbol_expr.get_identifier(), goto_programt::targett()});

    // Only create one call sequence per possible target:
    if(insertit.second)
    {
      goto_programt::targett t1=new_code_calls.add_instruction();
      t1->source_location=vcall_source_loc;
      if(!fun.symbol_expr.get_identifier().empty())
      {
      // call function
        t1->make_function_call(code);
        auto &newcall=to_code_function_call(t1->code);
        newcall.function()=fun.symbol_expr;
        pointer_typet need_type(symbol_typet(fun.symbol_expr.get(ID_C_class)));
        if(!type_eq(newcall.arguments()[0].type(), need_type, ns))
          newcall.arguments()[0].make_typecast(need_type);
      }
      else
      {
        // No definition for this type; shouldn't be possible...
        t1->make_assertion(false_exprt());
      }
      insertit.first->second=t1;
      // goto final
      goto_programt::targett t3=new_code_calls.add_instruction();
      t3->source_location=vcall_source_loc;
      t3->make_goto(t_final, true_exprt());
    }

    // If this calls the base function we just fall through.
    // Otherwise branch to the right call:
    if(fun.symbol_expr!=base_function_symbol)
    {
      exprt c_id1=constant_exprt(fun.class_id, string_typet());
      goto_programt::targett t4=new_code_gotos.add_instruction();
      t4->source_location=vcall_source_loc;
      t4->make_goto(insertit.first->second, equal_exprt(c_id1, c_id2));
    }
  }

  goto_programt new_code;

  // patch them all together
  new_code.destructive_append(new_code_gotos);
  new_code.destructive_append(new_code_calls);
  new_code.destructive_append(final_skip);

  // set locations
  Forall_goto_program_instructions(it, new_code)
  {
    const irep_idt property_class=it->source_location.get_property_class();
    const irep_idt comment=it->source_location.get_comment();
    it->source_location=target->source_location;
    it->function=target->function;
    if(!property_class.empty())
      it->source_location.set_property_class(property_class);
    if(!comment.empty())
      it->source_location.set_comment(comment);
  }

  goto_programt::targett next_target=target;
  next_target++;

  goto_program.destructive_insert(next_target, new_code);

  // finally, kill original invocation
  target->make_skip();
}
codet java_bytecode_convertt::convert_instructions(
  const instructionst &instructions,
  const code_typet &method_type)
{
  // Run a worklist algorithm, assuming that the bytecode has not
  // been tampered with. See "Leroy, X. (2003). Java bytecode
  // verification: algorithms and formalizations. Journal of Automated
  // Reasoning, 30(3-4), 235-269." for a more complete treatment.

  // first pass: get targets and map addresses to instructions
  
  struct converted_instructiont
  {
    converted_instructiont(
      const instructionst::const_iterator &it,
      const codet &_code):source(it), code(_code), done(false)
    {
    }

    instructionst::const_iterator source;
    std::list<unsigned> successors;
    std::set<unsigned> predecessors;
    codet code;
    stackt stack;
    bool done;
  };
  
  typedef std::map<unsigned, converted_instructiont> address_mapt;
  address_mapt address_map;
  std::set<unsigned> targets;

  for(instructionst::const_iterator
      i_it=instructions.begin();
      i_it!=instructions.end();
      i_it++)
  {
    std::pair<address_mapt::iterator, bool> a_entry=
      address_map.insert(std::make_pair(
          i_it->address,
          converted_instructiont(i_it, code_skipt())));
    assert(a_entry.second);
    // addresses are strictly increasing, hence we must have inserted
    // a new maximal key
    assert(a_entry.first==--address_map.end());

    if(i_it->statement!="goto" &&
       i_it->statement!="return" &&
       !(i_it->statement==patternt("?return")) &&
       i_it->statement!="athrow")
    {
      instructionst::const_iterator next=i_it;
      if(++next!=instructions.end())
        a_entry.first->second.successors.push_back(next->address);
    }

    if(i_it->statement=="goto" ||
       i_it->statement==patternt("if_?cmp??") ||
       i_it->statement==patternt("if??") ||
       i_it->statement=="ifnonnull" ||
       i_it->statement=="ifnull")
    {
      assert(!i_it->args.empty());

      const unsigned target=safe_string2unsigned(
        id2string(to_constant_expr(i_it->args[0]).get_value()));
      targets.insert(target);

      a_entry.first->second.successors.push_back(target);
    }
    else if(i_it->statement=="tableswitch" ||
            i_it->statement=="lookupswitch")
    {
      bool is_label=true;
      for(instructiont::argst::const_iterator
          a_it=i_it->args.begin();
          a_it!=i_it->args.end();
          a_it++, is_label=!is_label)
      {
        if(is_label)
        {
          const unsigned target=safe_string2unsigned(
            id2string(to_constant_expr(*a_it).get_value()));
          targets.insert(target);
          a_entry.first->second.successors.push_back(target);
        }
      }
    }
  }

  for(address_mapt::iterator
      it=address_map.begin();
      it!=address_map.end();
      ++it)
  {
    for(unsigned s : it->second.successors)
    {
      address_mapt::iterator a_it=address_map.find(s);
      assert(a_it!=address_map.end());

      a_it->second.predecessors.insert(it->first);
    }
  }

  std::set<unsigned> working_set;
  if(!instructions.empty())
    working_set.insert(instructions.front().address);

  while(!working_set.empty())
  {
    std::set<unsigned>::iterator cur=working_set.begin();
    address_mapt::iterator a_it=address_map.find(*cur);
    assert(a_it!=address_map.end());
    working_set.erase(cur);

    if(a_it->second.done) continue;
    working_set.insert(a_it->second.successors.begin(),
                       a_it->second.successors.end());

    instructionst::const_iterator i_it=a_it->second.source;
    stack.swap(a_it->second.stack);
    a_it->second.stack.clear();
    codet &c=a_it->second.code;

    assert(stack.empty() ||
           a_it->second.predecessors.size()<=1 ||
           has_prefix(stack.front().get_string(ID_C_base_name),
                      "$stack"));

    irep_idt statement=i_it->statement;
    exprt arg0=i_it->args.size()>=1?i_it->args[0]:nil_exprt();
    exprt arg1=i_it->args.size()>=2?i_it->args[1]:nil_exprt();

    const bytecode_infot &bytecode_info=get_bytecode_info(statement);

    // deal with _idx suffixes
    if(statement.size()>=2 &&
       statement[statement.size()-2]=='_' &&
       isdigit(statement[statement.size()-1]))
    {
      arg0=constant_exprt(
        std::string(id2string(statement), statement.size()-1, 1),
        integer_typet());
      statement=std::string(id2string(statement), 0, statement.size()-2);
    }
    
    exprt::operandst op=pop(bytecode_info.pop);
    exprt::operandst results;
    results.resize(bytecode_info.push, nil_exprt());
    
    if(statement=="aconst_null")
    {
      assert(results.size()==1);
      results[0]=gen_zero(java_reference_type(void_typet()));
    }
    else if(statement=="athrow")
    {
      assert(op.size()==1 && results.size()==1);
      side_effect_expr_throwt throw_expr;
      throw_expr.add_source_location()=i_it->source_location;
      throw_expr.copy_to_operands(op[0]);
      c=code_expressiont(throw_expr);
      results[0]=op[0];
    }
    else if(statement=="checkcast")
    {
      // checkcast throws an exception in case a cast of object
      // on stack to given type fails.
      // The stack isn't modified.
      assert(op.size()==1 && results.size()==1);
      results[0]=op[0];
    }
    else if(statement=="invokedynamic")
    {
      // not used in Java
      code_typet &code_type=to_code_type(arg0.type());
      const code_typet::parameterst &parameters(code_type.parameters());

      pop(parameters.size());

      const typet &return_type=code_type.return_type();

      if(return_type.id()!=ID_empty)
      {
        results.resize(1);
        results[0]=nil_exprt();
      }
    }
    else if(statement=="invokeinterface" ||
            statement=="invokespecial" ||
            statement=="invokevirtual" ||
            statement=="invokestatic")
    {
      const bool use_this(statement != "invokestatic");
      const bool is_virtual(
        statement == "invokevirtual" || statement == "invokeinterface");
      
      code_typet &code_type=to_code_type(arg0.type());
      code_typet::parameterst &parameters(code_type.parameters());

      if(use_this)
      {
        if(parameters.empty() || !parameters[0].get_this())
        {
          const empty_typet empty;
          pointer_typet object_ref_type(empty);
          code_typet::parametert this_p(object_ref_type);
          this_p.set_this();
          this_p.set_base_name("this");
          parameters.insert(parameters.begin(), this_p);
        }
      }

      code_function_callt call;
      call.add_source_location()=i_it->source_location;
      call.arguments() = pop(parameters.size());

      // double-check a bit      
      if(use_this)
      {
        const exprt &this_arg=call.arguments().front();
        assert(this_arg.type().id()==ID_pointer);
      }
      
      // do some type adjustment for the arguments,
      // as Java promotes arguments

      for(unsigned i=0; i<parameters.size(); i++)
      {
        const typet &type=parameters[i].type();
        if(type==java_boolean_type() ||
           type==java_char_type() ||
           type==java_byte_type() ||
           type==java_short_type())
        {
          assert(i<call.arguments().size());
          call.arguments()[i].make_typecast(type);
        }
      }
      
      // do some type adjustment for return values

      const typet &return_type=code_type.return_type();

      if(return_type.id()!=ID_empty)
      {
        // return types are promoted in Java
        call.lhs()=tmp_variable("return", return_type);
        exprt promoted=java_bytecode_promotion(call.lhs());
        results.resize(1);
        results[0]=promoted;
      }

      assert(arg0.id()==ID_virtual_function);

      // does the function symbol exist?
      irep_idt id=arg0.get(ID_identifier);

      if(symbol_table.symbols.find(id)==symbol_table.symbols.end())
      {
        // no, create stub
        symbolt symbol;
        symbol.name=id;
        symbol.base_name=arg0.get(ID_C_base_name);
        symbol.type=arg0.type();
        symbol.value.make_nil();
        symbol.mode=ID_java;
        symbol_table.add(symbol);
      }

      if(is_virtual)
      {
        // dynamic binding
        assert(use_this);
        assert(!call.arguments().empty());
        call.function()=arg0;
      }
      else
      {
        // static binding
	/*if(id == "java::java.lang.String.charAt:(I)C")
	  call.function()=symbol_exprt("java::__CPROVER_uninterpreted_char_at", arg0.type());
	  else*/
	  call.function()=symbol_exprt(arg0.get(ID_identifier), arg0.type());

      }

      call.function().add_source_location()=i_it->source_location;
      c = call;
      
    }
    else if(statement=="return")
    {
      assert(op.empty() && results.empty());
      c=code_returnt();
    }
    else if(statement==patternt("?return"))
    {
      // Return types are promoted in java, so this might need
      // conversion.
      assert(op.size()==1 && results.empty());
      exprt r=op[0];
      if(r.type()!=method_return_type) r=typecast_exprt(r, method_return_type);
      c=code_returnt(r);
    }
    else if(statement==patternt("?astore"))
    {
      assert(op.size()==3 && results.empty());
      
      char type_char=statement[0];
      
      exprt pointer=
        typecast_exprt(op[0], java_array_type(type_char));

      const dereference_exprt deref(pointer, pointer.type().subtype());

      const member_exprt data_ptr(
        deref, "data", pointer_typet(java_type_from_char(type_char)));

      plus_exprt data_plus_offset(data_ptr, op[1], data_ptr.type());
      typet element_type=data_ptr.type().subtype();
      const dereference_exprt element(data_plus_offset, element_type);

      c=code_assignt(element, op[2]);
    }
    else if(statement==patternt("?store"))
    {
      // store value into some local variable
      assert(op.size()==1 && results.empty());

      exprt var=variable(arg0, statement[0]);
      
      const bool is_array('a' == statement[0]);
      
      if(is_array)
        var.type()=op[0].type();

      c=code_assignt(var, op[0]);
    }
    else if(statement==patternt("?aload"))
    {
      assert(op.size() == 2 && results.size() == 1);
      
      char type_char=statement[0];

      exprt pointer=
        typecast_exprt(op[0], java_array_type(type_char));

      const dereference_exprt deref(pointer, pointer.type().subtype());

      const member_exprt data_ptr(
        deref, "data", pointer_typet(java_type_from_char(type_char)));

      plus_exprt data_plus_offset(data_ptr, op[1], data_ptr.type());
      typet element_type=data_ptr.type().subtype();
      dereference_exprt element(data_plus_offset, element_type);

      results[0]=java_bytecode_promotion(element);
    }
    else if(statement==patternt("?load"))
    {
      // load a value from a local variable
      results[0]=variable(arg0, statement[0]);
    }
    else if(statement=="ldc" || statement=="ldc_w" ||
            statement=="ldc2" || statement=="ldc2_w")
    {
      assert(op.empty() && results.size()==1);
      
      // 1) Pushing a String causes a reference to a java.lang.String object
      // to be constructed and pushed onto the operand stack.

      // 2) Pushing an int or a float causes a primitive value to be pushed
      // onto the stack.
      
      // 3) Pushing a Class constant causes a reference to a java.lang.Class
      // to be pushed onto the operand stack
      
      if(arg0.id()==ID_java_string_literal)
      {
        // these need to be references to java.lang.String
        results[0]=arg0;
        symbol_typet string_type("java::java.lang.String");
        results[0].type()=pointer_typet(string_type);
      }
      else if(arg0.id()==ID_type)
      {
        irep_idt class_id=arg0.type().get(ID_identifier);
        symbol_typet java_lang_Class("java::java.lang.Class");
        symbol_exprt symbol_expr(id2string(class_id)+"@class_model", java_lang_Class);
        address_of_exprt address_of_expr(symbol_expr);
        results[0]=address_of_expr;
      }
      else if(arg0.id()==ID_constant)
      {
        results[0]=arg0;
      }
      else
      {
        error() << "unexpected ldc argument" << eom;
        throw 0;
      }
      
    }
    else if(statement=="goto" || statement=="goto_w")
    {
      assert(op.empty() && results.empty());
      irep_idt number=to_constant_expr(arg0).get_value();
      code_gotot code_goto(label(number));
      c=code_goto;
    }
    else if(statement=="iconst_m1")
    {
      assert(results.size()==1);
      results[0]=from_integer(-1, java_int_type());
    }
    else if(statement==patternt("?const"))
    {
      assert(results.size() == 1);

      const char type_char=statement[0];
      const bool is_double('d' == type_char);
      const bool is_float('f' == type_char);

      if(is_double || is_float)
      {
        const ieee_float_spect spec(
            is_float ?
                ieee_float_spect::single_precision() :
                ieee_float_spect::double_precision());

        ieee_floatt value(spec);
        const typet &arg_type(arg0.type());
        if(ID_integer == arg_type.id())
          value.from_integer(arg0.get_int(ID_value));
        else
          value.from_expr(to_constant_expr(arg0));

        results[0] = value.to_expr();
      }
      else
      {
        const unsigned int value(arg0.get_unsigned_int(ID_value));
        const typet type=java_type_from_char(statement[0]);
        results[0] = as_number(value, type);
      }
    }
    else if(statement==patternt("?ipush"))
    {
      assert(results.size()==1);
      results[0]=typecast_exprt(arg0, java_int_type());
    }
    else if(statement==patternt("if_?cmp??"))
    {
      irep_idt number=to_constant_expr(arg0).get_value();
      assert(op.size()==2 && results.empty());

      code_ifthenelset code_branch;
      const irep_idt cmp_op=get_if_cmp_operator(statement);
      
      binary_relation_exprt condition(op[0], cmp_op, op[1]);

      cast_if_necessary(condition);
      code_branch.cond()=condition;
      code_branch.then_case()=code_gotot(label(number));
      code_branch.then_case().add_source_location()=i_it->source_location;
      code_branch.add_source_location()=i_it->source_location;
      
      c=code_branch;
    }
    else if(statement==patternt("if??"))
    {
      const irep_idt id=
        statement=="ifeq"?ID_equal:
        statement=="ifne"?ID_notequal:
        statement=="iflt"?ID_lt:
        statement=="ifge"?ID_ge:
        statement=="ifgt"?ID_gt:
        statement=="ifle"?ID_le:
        (assert(false), "");

      irep_idt number=to_constant_expr(arg0).get_value();
      assert(op.size()==1 && results.empty());

      code_ifthenelset code_branch;
      code_branch.cond()=binary_relation_exprt(op[0], id, gen_zero(op[0].type()));
      code_branch.cond().add_source_location()=i_it->source_location;
      code_branch.then_case()=code_gotot(label(number));
      code_branch.then_case().add_source_location()=i_it->source_location;
      code_branch.add_source_location()=i_it->source_location;

      c=code_branch;
    }
    else if(statement==patternt("ifnonnull"))
    {
      irep_idt number=to_constant_expr(arg0).get_value();
      assert(op.size()==1 && results.empty());
      code_ifthenelset code_branch;
      const typecast_exprt lhs(op[0], pointer_typet());
      const exprt rhs(gen_zero(lhs.type()));
      code_branch.cond()=binary_relation_exprt(lhs, ID_notequal, rhs);
      code_branch.then_case()=code_gotot(label(number));
      code_branch.then_case().add_source_location()=i_it->source_location;
      code_branch.add_source_location()=i_it->source_location;

      c=code_branch;
    }
    else if(statement==patternt("ifnull"))
    {
      assert(op.size()==1 && results.empty());
      irep_idt number=to_constant_expr(arg0).get_value();
      code_ifthenelset code_branch;
      const typecast_exprt lhs(op[0], pointer_typet(empty_typet()));
      const exprt rhs(gen_zero(lhs.type()));
      code_branch.cond()=binary_relation_exprt(lhs, ID_equal, rhs);
      code_branch.then_case()=code_gotot(label(number));
      code_branch.then_case().add_source_location()=i_it->source_location;
      code_branch.add_source_location()=i_it->source_location;

      c=code_branch;
    }
    else if(statement=="iinc")
    {
      code_assignt code_assign;
      code_assign.lhs()=variable(arg0, 'i');
      code_assign.rhs()=plus_exprt(
                          variable(arg0, 'i'),
                          typecast_exprt(arg1, java_int_type()));
      c=code_assign;
    }
    else if(statement==patternt("?xor"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=bitxor_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?or"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=bitor_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?and"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=bitand_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?shl"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=shl_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?shr"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=ashr_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?ushr"))
    {
      assert(op.size()==2 && results.size()==1);
      const typet type(java_type_from_char(statement[0]));

      const unsigned int width(type.get_unsigned_int(ID_width));
      typet target=unsigned_long_int_type();
      target.set(ID_width, width);

      const typecast_exprt lhs(op[0], target);
      const typecast_exprt rhs(op[1], target);

      results[0]=lshr_exprt(lhs, rhs);
    }
    else if(statement==patternt("?add"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=plus_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?sub"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=minus_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?div"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=div_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?mul"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=mult_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?neg"))
    {
      assert(op.size()==1 && results.size()==1);
      results[0]=unary_minus_exprt(op[0], op[0].type());
    }
    else if(statement==patternt("?rem"))
    {
      assert(op.size()==2 && results.size()==1);
      if(statement=="frem" || statement=="drem")
        results[0]=rem_exprt(op[0], op[1]);
      else
        results[0]=mod_exprt(op[0], op[1]);
    }
    else if(statement==patternt("?cmp"))
    {
      assert(op.size() == 2 && results.size() == 1);

      // The integer result on the stack is:
      //  0 if op[0] equals op[1]
      // -1 if op[0] is less than op[1]
      //  1 if op[0] is greater than op[1]

      const typet t=java_int_type();

      results[0]=
        if_exprt(binary_relation_exprt(op[0], ID_equal, op[1]), gen_zero(t),
        if_exprt(binary_relation_exprt(op[0], ID_gt, op[1]), from_integer(1, t),
        from_integer(-1, t)));
    }
    else if(statement==patternt("?cmp?"))
    {
      assert(op.size()==2 && results.size()==1);
      const floatbv_typet type(to_floatbv_type(java_type_from_char(statement[0])));
      const ieee_float_spect spec(type);
      const ieee_floatt nan(ieee_floatt::NaN(spec));
      const constant_exprt nan_expr(nan.to_expr());
      const int nan_value(statement[4] == 'l' ? -1 : 1);
      const typet result_type(java_int_type());
      const exprt nan_result(from_integer(nan_value, result_type));

      // (value1 == NaN || value2 == NaN) ? nan_value : value1  < value2 ? -1 : value2 < value1  1 ? 1 : 0;
      // (value1 == NaN || value2 == NaN) ? nan_value : value1 == value2 ? 0  : value1 < value2 -1 ? 1 : 0;

      results[0]=
        if_exprt(or_exprt(ieee_float_equal_exprt(nan_expr, op[0]), ieee_float_equal_exprt(nan_expr, op[1])), nan_result,
        if_exprt(ieee_float_equal_exprt(op[0], op[1]), gen_zero(result_type),
        if_exprt(binary_relation_exprt(op[0], ID_lt, op[1]), from_integer(-1, result_type), from_integer(1, result_type))));
    }
    else if(statement==patternt("?cmpl"))
    {
      assert(op.size()==2 && results.size()==1);
      results[0]=binary_relation_exprt(op[0], ID_lt, op[1]);
    }
    else if(statement=="dup")
    {
      assert(op.size()==1 && results.size()==2);
      results[0]=results[1]=op[0];
    }
    else if(statement=="dup_x1")
    {
      assert(op.size()==2 && results.size()==3);
      results[0]=op[1];
      results[1]=op[0];
      results[2]=op[1];
    }
    else if(statement=="dup_x2")
    {
      assert(op.size()==3 && results.size()==4);
      results[0]=op[2];
      results[1]=op[0];
      results[2]=op[1];
      results[3]=op[2];
    }
    // dup2* behaviour depends on the size of the operands on the
    // stack
    else if(statement=="dup2")
    {
      assert(!stack.empty() && results.empty());

      if(stack.back().type().get_unsigned_int(ID_width)==32)
        op=pop(2);
      else
        op=pop(1);

      results.insert(results.end(), op.begin(), op.end());
      results.insert(results.end(), op.begin(), op.end());
    }
    else if(statement=="dup2_x1")
    {
      assert(!stack.empty() && results.empty());

      if(stack.back().type().get_unsigned_int(ID_width)==32)
        op=pop(3);
      else
        op=pop(2);

      results.insert(results.end(), op.begin()+1, op.end());
      results.insert(results.end(), op.begin(), op.end());
    }
    else if(statement=="dup2_x2")
    {
      assert(!stack.empty() && results.empty());

      if(stack.back().type().get_unsigned_int(ID_width)==32)
        op=pop(2);
      else
        op=pop(1);

      assert(!stack.empty());
      exprt::operandst op2;

      if(stack.back().type().get_unsigned_int(ID_width)==32)
        op2=pop(2);
      else
        op2=pop(1);

      results.insert(results.end(), op.begin(), op.end());
      results.insert(results.end(), op2.begin(), op2.end());
      results.insert(results.end(), op.begin(), op.end());
    }
    else if(statement=="dconst")
    {
      assert(op.empty() && results.size()==1);
    }
    else if(statement=="fconst")
    {
      assert(op.empty() && results.size()==1);
    }
    else if(statement=="getfield")
    {
      assert(op.size()==1 && results.size()==1);
      results[0]=to_member(op[0], arg0);
    }
    else if(statement=="getstatic")
    {
      assert(op.empty() && results.size()==1);
      symbol_exprt symbol_expr(arg0.type());
      symbol_expr.set_identifier(arg0.get_string(ID_class)+"."+arg0.get_string(ID_component_name));
      results[0]=symbol_expr;
    }
    else if(statement=="putfield")
    {
      assert(op.size()==2 && results.size()==0);
      c = code_assignt(to_member(op[0], arg0), op[1]);
    }
    else if(statement=="putstatic")
    {
      assert(op.size()==1 && results.empty());
      symbol_exprt symbol_expr(arg0.type());
      symbol_expr.set_identifier(arg0.get_string(ID_class)+"."+arg0.get_string(ID_component_name));
      c=code_assignt(symbol_expr, op[0]);
    }
    else if(statement==patternt("?2?")) // i2c etc.
    {
      assert(op.size()==1 && results.size()==1);
      results[0]=typecast_exprt(op[0], java_type_from_char(statement[2]));
    }
    else if(statement=="new")
    {
      // use temporary since the stack symbol might get duplicated
      assert(op.empty() && results.size()==1);
      const pointer_typet ref_type(arg0.type());
      exprt java_new_expr=side_effect_exprt(ID_java_new, ref_type);

      if(!i_it->source_location.get_line().empty())
        java_new_expr.add_source_location()=i_it->source_location;

      const exprt tmp=tmp_variable("new", ref_type);
      c=code_assignt(tmp, java_new_expr);
      results[0]=tmp;
    }
    else if(statement=="newarray" ||
            statement=="anewarray")
    {
      // the op is the array size
      assert(op.size()==1 && results.size()==1);

      char element_type;
      
      if(statement=="newarray")
      {
        irep_idt id=arg0.type().id();

        if(id==ID_bool)
          element_type='z';
        else if(id==ID_char)
          element_type='c';
        else if(id==ID_float)
          element_type='f';
        else if(id==ID_double)
          element_type='d';
        else if(id==ID_byte)
          element_type='b';
        else if(id==ID_short)
          element_type='s';
        else if(id==ID_int)
          element_type='i';
        else if(id==ID_long)
          element_type='j';
        else
          element_type='?';
      }
      else
        element_type='a';

      const pointer_typet ref_type=java_array_type(element_type);

      side_effect_exprt java_new_array(ID_java_new_array, ref_type);
      java_new_array.copy_to_operands(op[0]);

      if(!i_it->source_location.get_line().empty())
        java_new_array.add_source_location()=i_it->source_location;

      const exprt tmp=tmp_variable("newarray", ref_type);
      c=code_assignt(tmp, java_new_array);
      results[0]=tmp;
    }
    else if(statement=="multianewarray")
    {
      // The first argument is the type, the second argument is the dimension.
      // The size of each dimension is on the stack.
      irep_idt number=to_constant_expr(arg1).get_value();
      unsigned dimension=safe_c_str2unsigned(number.c_str());

      op=pop(dimension);
      assert(results.size()==1);

      // arg0.type()
      const pointer_typet ref_type=java_array_type('a');

      side_effect_exprt java_new_array(ID_java_new_array, ref_type);
      java_new_array.operands()=op;

      if(!i_it->source_location.get_line().empty())
        java_new_array.add_source_location()=i_it->source_location;

      const exprt tmp=tmp_variable("newarray", ref_type);
      c=code_assignt(tmp, java_new_array);
      results[0]=tmp;
    }
    else if(statement=="arraylength")
    {
      assert(op.size()==1 && results.size()==1);

      exprt pointer=
        typecast_exprt(op[0], java_array_type(statement[0]));

      const dereference_exprt array(pointer, pointer.type().subtype());
      assert(pointer.type().subtype().id()==ID_symbol);

      const member_exprt length(array, "length", java_int_type());

      results[0]=length;
    }
    else if(statement=="tableswitch" ||
            statement=="lookupswitch")
    {
      assert(op.size()==1 && results.size()==0);

      // we turn into switch-case
      code_switcht code_switch;
      code_switch.add_source_location()=i_it->source_location;
      code_switch.value()=op[0];
      code_blockt code_block;
      code_block.add_source_location()=i_it->source_location;

      bool is_label=true;
      for(instructiont::argst::const_iterator
          a_it=i_it->args.begin();
          a_it!=i_it->args.end();
          a_it++, is_label=!is_label)
      {
        if(is_label)
        {
          code_switch_caset code_case;
          code_case.add_source_location()=i_it->source_location;

          irep_idt number=to_constant_expr(*a_it).get_value();
          code_case.code()=code_gotot(label(number));
          code_case.code().add_source_location()=i_it->source_location;
        
          if(a_it==i_it->args.begin())
            code_case.set_default();
          else
          {
            instructiont::argst::const_iterator prev=a_it;
            prev--;
            code_case.case_op()=typecast_exprt(*prev, op[0].type());
            code_case.case_op().add_source_location()=i_it->source_location;
          }
          
          code_block.add(code_case);
        }
      }
      
      code_switch.body()=code_block;
      c=code_switch;
    }
    else if(statement=="pop" || statement=="pop2")
    {
      // these are skips
      c=code_skipt();

      // pop2 removes two single-word items from the stack (e.g. two
      // integers, or an integer and an object reference) or one
      // two-word item (i.e. a double or a long).
      // http://cs.au.dk/~mis/dOvs/jvmspec/ref-pop2.html
      if(statement=="pop2" &&
         op[0].type().get_unsigned_int(ID_width)==32)
        pop(1);
    }
    else if(statement=="instanceof")
    {
      assert(op.size()==1 && results.size()==1);

      results[0]=
        binary_predicate_exprt(op[0], "java_instanceof", arg0);
    }
    else
    {
      c=codet(statement);
      c.operands()=op;
    }
    
    if(!i_it->source_location.get_line().empty())
      c.add_source_location()=i_it->source_location;

    push(results);

    a_it->second.done=true;
    for(std::list<unsigned>::iterator
        it=a_it->second.successors.begin();
        it!=a_it->second.successors.end();
        ++it)
    {
      address_mapt::iterator a_it2=address_map.find(*it);
      assert(a_it2!=address_map.end());

      if(!stack.empty() && a_it2->second.predecessors.size()>1)
      {
        // copy into temporaries
        code_blockt more_code;

        // introduce temporaries when successor is seen for the first
        // time
        if(a_it2->second.stack.empty())
        {
          for(stackt::iterator s_it=stack.begin();
              s_it!=stack.end();
              ++s_it)
          {
            symbol_exprt lhs=tmp_variable("$stack", s_it->type());
            code_assignt a(lhs, *s_it);
            more_code.copy_to_operands(a);

            s_it->swap(lhs);
          }
        }
        else
        {
          assert(a_it2->second.stack.size()==stack.size());
          stackt::const_iterator os_it=a_it2->second.stack.begin();
          for(stackt::iterator s_it=stack.begin();
              s_it!=stack.end();
              ++s_it)
          {
            assert(has_prefix(os_it->get_string(ID_C_base_name),
                              "$stack"));
            symbol_exprt lhs=to_symbol_expr(*os_it);
            code_assignt a(lhs, *s_it);
            more_code.copy_to_operands(a);

            s_it->swap(lhs);
            ++os_it;
          }
        }

        if(results.empty())
        {
          more_code.copy_to_operands(c);
          c.swap(more_code);
        }
        else
        {
          c.make_block();
          forall_operands(o_it, more_code)
            c.copy_to_operands(*o_it);
        }
      }

      a_it2->second.stack=stack;
    }
  }

  // TODO: add exception handlers from exception table
  // review successor computation of athrow!
  code_blockt code;
  
  // temporaries
  for(const auto & var : tmp_vars)
  {
    code.add(code_declt(var));
  }

  for(const auto & it : address_map)
  {
    const unsigned address=it.first;
    assert(it.first==it.second.source->address);
    const codet &c=it.second.code;

    if(targets.find(address)!=targets.end())
      code.add(code_labelt(label(i2string(address)), c));
    else if(c.get_statement()!=ID_skip)
      code.add(c);
  }

  return code;
}
Example #9
0
void remove_virtual_functionst::remove_virtual_function(
  goto_programt &goto_program,
  goto_programt::targett target)
{
  const code_function_callt &code=
    to_code_function_call(target->code);

  const exprt &function=code.function();
  assert(function.id()==ID_virtual_function);
  assert(!code.arguments().empty());
  
  functionst functions;
  get_functions(function, functions);
  
  if(functions.empty())
  {
    target->make_skip();
    return; // give up
  }

  // the final target is a skip
  goto_programt final_skip;

  goto_programt::targett t_final=final_skip.add_instruction();
  t_final->make_skip();
  
  // build the calls and gotos

  goto_programt new_code_calls;
  goto_programt new_code_gotos;

  for(functionst::const_iterator
      it=functions.begin();
      it!=functions.end();
      it++)
  {
    // call function
    goto_programt::targett t1=new_code_calls.add_instruction();
    t1->make_function_call(code);
    to_code_function_call(t1->code).function()=it->symbol_expr;
    
    // goto final
    goto_programt::targett t3=new_code_calls.add_instruction();
    t3->make_goto(t_final, true_exprt());

    exprt this_expr=code.arguments()[0];    
    if(this_expr.type().id()!=ID_pointer ||
       this_expr.type().id()!=ID_struct)
    {
      symbol_typet symbol_type(it->class_id);
      this_expr=typecast_exprt(this_expr, pointer_typet(symbol_type));
    }
    
    exprt deref=dereference_exprt(this_expr, this_expr.type().subtype());
    exprt c_id1=constant_exprt(it->class_id, string_typet());
    exprt c_id2=build_class_identifier(deref);
    
    goto_programt::targett t4=new_code_gotos.add_instruction();
    t4->make_goto(t1, equal_exprt(c_id1, c_id2));
  }

  goto_programt new_code;
  
  // patch them all together
  new_code.destructive_append(new_code_gotos);
  new_code.destructive_append(new_code_calls);
  new_code.destructive_append(final_skip);
  
  // set locations
  Forall_goto_program_instructions(it, new_code)
  {
    irep_idt property_class=it->source_location.get_property_class();
    irep_idt comment=it->source_location.get_comment();
    it->source_location=target->source_location;
    it->function=target->function;
    if(!property_class.empty()) it->source_location.set_property_class(property_class);
    if(!comment.empty()) it->source_location.set_comment(comment);
  }
Example #10
0
exprt boolbvt::bv_get_rec(
    const bvt &bv,
    const std::vector<bool> &unknown,
    std::size_t offset,
    const typet &type) const
{
    if(type.id()==ID_symbol)
        return bv_get_rec(bv, unknown, offset, ns.follow(type));

    std::size_t width=boolbv_width(type);

    assert(bv.size()==unknown.size());
    assert(bv.size()>=offset+width);

    if(type.id()==ID_bool)
    {
        if(!unknown[offset])
        {
            switch(prop.l_get(bv[offset]).get_value())
            {
            case tvt::tv_enumt::TV_FALSE:
                return false_exprt();
            case tvt::tv_enumt::TV_TRUE:
                return true_exprt();
            default:
                return false_exprt(); // default
            }
        }

        return nil_exprt();
    }

    bvtypet bvtype=get_bvtype(type);

    if(bvtype==IS_UNKNOWN)
    {
        if(type.id()==ID_array)
        {
            const typet &subtype=type.subtype();
            std::size_t sub_width=boolbv_width(subtype);

            if(sub_width!=0)
            {
                exprt::operandst op;
                op.reserve(width/sub_width);

                for(std::size_t new_offset=0;
                        new_offset<width;
                        new_offset+=sub_width)
                {
                    op.push_back(
                        bv_get_rec(bv, unknown, offset+new_offset, subtype));
                }

                exprt dest=exprt(ID_array, type);
                dest.operands().swap(op);
                return dest;
            }
        }
        else if(type.id()==ID_struct_tag)
        {
            return bv_get_rec(bv, unknown, offset, ns.follow_tag(to_struct_tag_type(type)));
        }
        else if(type.id()==ID_union_tag)
        {
            return bv_get_rec(bv, unknown, offset, ns.follow_tag(to_union_tag_type(type)));
        }
        else if(type.id()==ID_struct)
        {
            const struct_typet &struct_type=to_struct_type(type);
            const struct_typet::componentst &components=struct_type.components();
            std::size_t new_offset=0;
            exprt::operandst op;
            op.reserve(components.size());

            for(struct_typet::componentst::const_iterator
                    it=components.begin();
                    it!=components.end();
                    it++)
            {
                const typet &subtype=ns.follow(it->type());
                op.push_back(nil_exprt());

                std::size_t sub_width=boolbv_width(subtype);

                if(sub_width!=0)
                {
                    op.back()=bv_get_rec(bv, unknown, offset+new_offset, subtype);
                    new_offset+=sub_width;
                }
            }

            struct_exprt dest(type);
            dest.operands().swap(op);
            return dest;
        }
        else if(type.id()==ID_union)
        {
            const union_typet &union_type=to_union_type(type);
            const union_typet::componentst &components=union_type.components();

            assert(!components.empty());

            // Any idea that's better than just returning the first component?
            std::size_t component_nr=0;

            union_exprt value(union_type);

            value.set_component_name(
                components[component_nr].get_name());

            const typet &subtype=components[component_nr].type();

            value.op()=bv_get_rec(bv, unknown, offset, subtype);

            return value;
        }
        else if(type.id()==ID_vector)
        {
            const typet &subtype=ns.follow(type.subtype());
            std::size_t sub_width=boolbv_width(subtype);

            if(sub_width!=0 && width%sub_width==0)
            {
                std::size_t size=width/sub_width;
                exprt value(ID_vector, type);
                value.operands().resize(size);

                for(std::size_t i=0; i<size; i++)
                    value.operands()[i]=
                        bv_get_rec(bv, unknown, i*sub_width, subtype);

                return value;
            }
        }
        else if(type.id()==ID_complex)
        {
            const typet &subtype=ns.follow(type.subtype());
            std::size_t sub_width=boolbv_width(subtype);

            if(sub_width!=0 && width==sub_width*2)
            {
                exprt value(ID_complex, type);
                value.operands().resize(2);

                value.op0()=bv_get_rec(bv, unknown, 0*sub_width, subtype);
                value.op1()=bv_get_rec(bv, unknown, 1*sub_width, subtype);

                return value;
            }
        }
    }

    std::string value;

    for(std::size_t bit_nr=offset; bit_nr<offset+width; bit_nr++)
    {
        char ch;
        if(unknown[bit_nr])
            ch='0';
        else
            switch(prop.l_get(bv[bit_nr]).get_value())
            {
            case tvt::tv_enumt::TV_FALSE:
                ch='0';
                break;
            case tvt::tv_enumt::TV_TRUE:
                ch='1';
                break;
            case tvt::tv_enumt::TV_UNKNOWN:
                ch='0';
                break;
            default:
                assert(false);
            }

        value=ch+value;
    }

    switch(bvtype)
    {
    case IS_UNKNOWN:
        if(type.id()==ID_string)
        {
            mp_integer int_value=binary2integer(value, false);
            irep_idt s;
            if(int_value>=string_numbering.size())
                s=irep_idt();
            else
                s=string_numbering[int_value.to_long()];

            return constant_exprt(s, type);
        }
        break;

    case IS_RANGE:
    {
        mp_integer int_value=binary2integer(value, false);
        mp_integer from=string2integer(type.get_string(ID_from));

        constant_exprt value_expr(type);
        value_expr.set_value(integer2string(int_value+from));
        return value_expr;
    }
    break;

    default:
    case IS_C_ENUM:
        constant_exprt value_expr(type);
        value_expr.set_value(value);
        return value_expr;
    }

    return nil_exprt();
}
Example #11
0
constant_exprt constant_exprt::integer_constant(unsigned v)
{
  return constant_exprt(std::to_string(v), integer_typet());
}
bool clang_c_convertert::convert_float_literal(
  const clang::FloatingLiteral &floating_literal,
  exprt &dest)
{
  if(!config.ansi_c.use_fixed_for_float)
  {
    std::cerr << "floatbv unsupported, sorry" << std::endl;
    return false;
  }

  typet type;
  if(get_type(floating_literal.getType(), type))
    return true;

  llvm::APFloat val = floating_literal.getValue();

  llvm::SmallVector<char, 32> string;
  val.toString(string, 32, 0);

  unsigned width = bv_width(type);
  mp_integer value;
  std::string float_string;

  if(!val.isInfinity())
  {
    mp_integer significand;
    mp_integer exponent;

    float_string = parse_float(string, significand, exponent);

    unsigned fraction_bits;
    const std::string &integer_bits = 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;
    value = significand * factor;

    if(exponent < 0)
      value /= power(10, -exponent);
    else
    {
      value *= power(10, exponent);

      if(value <= -power(2, width - 1) - 1)
      {
        // saturate: use "smallest value"
        value = -power(2, width - 1);
      }
    }
  }
  else
  {
    // saturate: use "biggest value"
    value = power(2, width - 1) - 1;
    float_string = "2147483647.99999999976716935634613037109375";
  }

  dest =
    constant_exprt(
      integer2binary(value, bv_width(type)),
      float_string,
      type);

  return false;
}