1

/*

     2

 *  matiec - a compiler for the programming languages defined in IEC 61131-3

     3

 *

     4

 *  Copyright (C) 2003-2011  Mario de Sousa (msousa@fe.up.pt)

     5

 *  Copyright (C) 2007-2011  Laurent Bessard and Edouard Tisserant

     6

 *

     7

 *  This program is free software: you can redistribute it and/or modify

     8

 *  it under the terms of the GNU General Public License as published by

     9

 *  the Free Software Foundation, either version 3 of the License, or

    10

 *  (at your option) any later version.

    11

 *

    12

 *  This program is distributed in the hope that it will be useful,

    13

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

    14

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    15

 *  GNU General Public License for more details.

    16

 *

    17

 *  You should have received a copy of the GNU General Public License

    18

 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.

    19

 *

    20

 * This code is made available on the understanding that it will not be

    21

 * used in safety-critical situations without a full and competent review.

    22

 *

    23

 * Based on the

    24

 * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

    25

 *

    26

 */

    27

    28

    29

/*

    30

 * Conversion of st statements (i.e. ST code).

    31

 *

    32

 * This is part of the 4th stage that generates

    33

 * a C source program equivalent to the IL and ST, or SFC

    34

 * code.

    35

 */

    36

    37

    41

/***********************************************************************/

    42

/***********************************************************************/

    43

/***********************************************************************/

    44

/***********************************************************************/

    45

    46

    47

class generate_c_st_c: public generate_c_typedecl_c {

    48

    49

  public:

    50

    typedef enum {

    51

      expression_vg,

    52

      assignment_vg,

    53

      complextype_base_vg,

    54

      complextype_suffix_vg,

    55

      fparam_output_vg

    56

    } variablegeneration_t;

    57

    58

  private:

    59

    /* When calling a function block, we must first find it's type,

    60

     * by searching through the declarations of the variables currently

    61

     * in scope.

    62

     * This class does just that...

    63

     * A new class is instantiated whenever we begin generating the code

    64

     * for a function block type declaration, or a program declaration.

    65

     * This object instance will then later be called while the

    66

     * function block's or the program's body is being handled.

    67

     *

    68

     * Note that functions cannot contain calls to function blocks,

    69

     * so we do not create an object instance when handling

    70

     * a function declaration.

    71

     */

    72

    search_fb_instance_decl_c *search_fb_instance_decl;

    73

    74

    /* When compiling st code, it becomes necessary to determine the

    75

     * data type of st expressions. To do this, we must first find the

    76

     * st operand's declaration, within the scope of the function block

    77

     * or function currently being processed.

    78

     * The following object does just that...

    79

     * This object instance will then later be called while the

    80

     * remaining st code is being handled.

    81

     */

    82

    search_expression_type_c *search_expression_type;

    83

    84

    search_varfb_instance_type_c *search_varfb_instance_type;

    85

    86

    search_base_type_c search_base_type;

    87

    88

    symbol_c* current_array_type;

    89

    symbol_c* current_param_type;

    90

    91

    int fcall_number;

    92

    symbol_c *fbname;

    93

    94

    variablegeneration_t wanted_variablegeneration;

    95

    96

  public:

    97

    generate_c_st_c(stage4out_c *s4o_ptr, symbol_c *name, symbol_c *scope, const char *variable_prefix = NULL)

    98

    : generate_c_typedecl_c(s4o_ptr) {

    99

      search_fb_instance_decl = new search_fb_instance_decl_c(scope);

   100

      search_expression_type = new search_expression_type_c(scope);

   101

      search_varfb_instance_type = new search_varfb_instance_type_c(scope);

   102

      this->set_variable_prefix(variable_prefix);

   103

      current_array_type = NULL;

   104

      current_param_type = NULL;

   105

      fcall_number = 0;

   106

      fbname = name;

   107

      wanted_variablegeneration = expression_vg;

   108

    }

   109

   110

    virtual ~generate_c_st_c(void) {

   111

      delete search_fb_instance_decl;

   112

      delete search_expression_type;

   113

      delete search_varfb_instance_type;

   114

    }

   115

   116

   117

  public:

   118

    void generate(statement_list_c *stl) {

   119

      stl->accept(*this);

   120

    }

   121

   122

  private:

   123

   124

void *print_getter(symbol_c *symbol) {

   125

  unsigned int vartype = search_varfb_instance_type->get_vartype(symbol);

   126

  if (wanted_variablegeneration == fparam_output_vg) {

   127

  	if (vartype == search_var_instance_decl_c::external_vt)

   128

      s4o.print(GET_EXTERNAL_BY_REF);

   129

    else if (vartype == search_var_instance_decl_c::located_vt)

   130

      s4o.print(GET_LOCATED_BY_REF);

   131

    else

   132

      s4o.print(GET_VAR_BY_REF);

   133

  }

   134

  else {

   135

	if (vartype == search_var_instance_decl_c::external_vt)

   136

	  s4o.print(GET_EXTERNAL);

   137

	else if (vartype == search_var_instance_decl_c::located_vt)

   138

	  s4o.print(GET_LOCATED);

   139

	else

   140

	  s4o.print(GET_VAR);

   141

  }

   142

  s4o.print("(");

   143

   144

  variablegeneration_t old_wanted_variablegeneration = wanted_variablegeneration;

   145

  wanted_variablegeneration = complextype_base_vg;

   146

  symbol->accept(*this);

   147

  if (search_varfb_instance_type->type_is_complex())

   148

    s4o.print(",");

   149

  wanted_variablegeneration = complextype_suffix_vg;

   150

  symbol->accept(*this);

   151

  s4o.print(")");

   152

  wanted_variablegeneration = old_wanted_variablegeneration;

   153

  return NULL;

   154

}

   155

   156

void *print_setter(symbol_c* symbol,

   157

		symbol_c* type,

   158

		symbol_c* value,

   159

		symbol_c* fb_symbol = NULL,

   160

		symbol_c* fb_value = NULL) {

   161

   162

  unsigned int vartype = search_varfb_instance_type->get_vartype(symbol);

   163

  if (vartype == search_var_instance_decl_c::external_vt) {

   164

    symbolic_variable_c *variable = dynamic_cast<symbolic_variable_c *>(symbol);

   165

    /* TODO Find a solution for forcing global complex variables */

   166

    if (variable != NULL) {

   167

      s4o.print(SET_EXTERNAL);

   168

      s4o.print("(");

   169

      variable->var_name->accept(*this);

   170

      s4o.print(",");

   171

    }

   172

    else {

   173

      s4o.print(SET_COMPLEX_EXTERNAL);

   174

      s4o.print("(");

   175

    }

   176

  }

   177

  else {

   178

    if (vartype == search_var_instance_decl_c::located_vt)

   179

      s4o.print(SET_LOCATED);

   180

    else

   181

      s4o.print(SET_VAR);

   182

    s4o.print("(");

   183

  }

   184

   185

  if (fb_symbol != NULL) {

   186

    print_variable_prefix();

   187

    fb_symbol->accept(*this);

   188

    s4o.print(".");

   189

  }

   190

  else

   191

    wanted_variablegeneration = complextype_base_vg;

   192

   193

  symbol->accept(*this);

   194

  s4o.print(",");

   195

  wanted_variablegeneration = expression_vg;

   196

  print_check_function(type, value, fb_value);

   197

  /* We need to call search_varfb_instance_type->get_vartype() again, as it may have been called

   198

   * again since we called it in the beginning of this print_setter() function.

   199

   * This make sure the call to search_varfb_instance_type->type_is_complex() will return

   200

   * the correct value regarding our 'symbol'.

   201

   */

   202

  search_varfb_instance_type->get_vartype(symbol);

   203

  if (search_varfb_instance_type->type_is_complex()) {

   204

    s4o.print(",");

   205

    wanted_variablegeneration = complextype_suffix_vg;

   206

    symbol->accept(*this);

   207

  }

   208

  s4o.print(")");

   209

  wanted_variablegeneration = expression_vg;

   210

  return NULL;

   211

}

   212

   213

/*********************/

   214

/* B 1.4 - Variables */

   215

/*********************/

   216

void *visit(symbolic_variable_c *symbol) {

   217

  unsigned int vartype;

   218

  if (wanted_variablegeneration == complextype_base_vg)

   219

         generate_c_base_c::visit(symbol);

   220

  else if (wanted_variablegeneration == complextype_suffix_vg)

   221

         return NULL;

   222

  else if (this->is_variable_prefix_null()) {

   223

         vartype = search_varfb_instance_type->get_vartype(symbol);

   224

         if (wanted_variablegeneration == fparam_output_vg) {

   225

           s4o.print("&(");

   226

           generate_c_base_c::visit(symbol);

   227

           s4o.print(")");

   228

         } 

   229

         else {

   230

           generate_c_base_c::visit(symbol);

   231

         }

   232

  }

   233

  else

   234

      print_getter(symbol);

   235

  return NULL;

   236

}

   237

   238

/********************************************/

   239

/* B.1.4.1   Directly Represented Variables */

   240

/********************************************/

   241

// direct_variable: direct_variable_token   {$$ = new direct_variable_c($1);};

   242

void *visit(direct_variable_c *symbol) {

   243

  TRACE("direct_variable_c");

   244

  /* Do not use print_token() as it will change everything into uppercase */

   245

  if (strlen(symbol->value) == 0) ERROR;

   246

  if (this->is_variable_prefix_null()) {

   247

    if (wanted_variablegeneration != fparam_output_vg)

   248

	  s4o.print("*(");

   249

  }

   250

  else {

   251

    switch (wanted_variablegeneration) {

   252

      case expression_vg:

   253

  	    s4o.print(GET_LOCATED);

   254

  	    s4o.print("(");

   255

  	    break;

   256

      case fparam_output_vg:

   257

        s4o.print(GET_LOCATED_BY_REF);

   258

        s4o.print("(");

   259

        break;

   260

      default:

   261

        break;

   262

    }

   263

  }

   264

  this->print_variable_prefix();

   265

  s4o.printlocation(symbol->value + 1);

   266

  if ((this->is_variable_prefix_null() && wanted_variablegeneration != fparam_output_vg) ||

   267

	  wanted_variablegeneration != assignment_vg)

   268

    s4o.print(")");

   269

  return NULL;

   270

}

   271

   272

/*************************************/

   273

/* B.1.4.2   Multi-element Variables */

   274

/*************************************/

   275

   276

// SYM_REF2(structured_variable_c, record_variable, field_selector)

   277

void *visit(structured_variable_c *symbol) {

   278

  TRACE("structured_variable_c");

   279

  switch (wanted_variablegeneration) {

   280

    case complextype_base_vg:

   281

      symbol->record_variable->accept(*this);

   282

      break;

   283

    case complextype_suffix_vg:

   284

      symbol->record_variable->accept(*this);

   285

      s4o.print(".");

   286

      symbol->field_selector->accept(*this);

   287

      break;

   288

    default:

   289

      if (this->is_variable_prefix_null()) {

   290

    	symbol->record_variable->accept(*this);

   291

    	s4o.print(".");

   292

    	symbol->field_selector->accept(*this);

   293

      }

   294

      else

   295

    	print_getter(symbol);

   296

      break;

   297

  }

   298

  return NULL;

   299

}

   300

   301

/*  subscripted_variable '[' subscript_list ']' */

   302

//SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

   303

void *visit(array_variable_c *symbol) {

   304

  switch (wanted_variablegeneration) {

   305

    case complextype_base_vg:

   306

      symbol->subscripted_variable->accept(*this);

   307

      break;

   308

    case complextype_suffix_vg:

   309

      symbol->subscripted_variable->accept(*this);

   310

   311

      current_array_type = search_varfb_instance_type->get_type_id(symbol->subscripted_variable);

   312

      if (current_array_type == NULL) ERROR;

   313

   314

      s4o.print(".table");

   315

      wanted_variablegeneration = expression_vg;

   316

      symbol->subscript_list->accept(*this);

   317

      wanted_variablegeneration = complextype_suffix_vg;

   318

   319

      current_array_type = NULL;

   320

      break;

   321

    default:

   322

      if (this->is_variable_prefix_null()) {

   323

    	symbol->subscripted_variable->accept(*this);

   324

   325

    	current_array_type = search_varfb_instance_type->get_type_id(symbol->subscripted_variable);

   326

    	if (current_array_type == NULL) ERROR;

   327

   328

    	s4o.print(".table");

   329

        symbol->subscript_list->accept(*this);

   330

   331

        current_array_type = NULL;

   332

      }

   333

      else

   334

    	print_getter(symbol);

   335

      break;

   336

  }

   337

  return NULL;

   338

}

   339

   340

/* subscript_list ',' subscript */

   341

void *visit(subscript_list_c *symbol) {

   342

  for (int i =  0; i < symbol->n; i++) {

   343

    s4o.print("[__");

   344

    current_array_type->accept(*this);

   345

    s4o.print("_TRANSIDX(");

   346

    print_integer(i);

   347

    s4o.print(",");

   348

    symbol->elements[i]->accept(*this);

   349

    s4o.print(")]");

   350

  }

   351

  return NULL;

   352

}

   353

   354

/******************************************/

   355

/* B 1.4.3 - Declaration & Initialisation */

   356

/******************************************/

   357

   358

/* helper symbol for structure_initialization */

   359

/* structure_element_initialization_list ',' structure_element_initialization */

   360

void *visit(structure_element_initialization_list_c *symbol) {

   361

  generate_c_structure_initialization_c *structure_initialization = new generate_c_structure_initialization_c(&s4o);

   362

  structure_initialization->init_structure_default(this->current_param_type);

   363

  structure_initialization->init_structure_values(symbol);

   364

  delete structure_initialization;

   365

  return NULL;

   366

}

   367

   368

/* helper symbol for array_initialization */

   369

/* array_initial_elements_list ',' array_initial_elements */

   370

void *visit(array_initial_elements_list_c *symbol) {

   371

  generate_c_array_initialization_c *array_initialization = new generate_c_array_initialization_c(&s4o);

   372

  array_initialization->init_array_size(this->current_param_type);

   373

  array_initialization->init_array_values(symbol);

   374

  delete array_initialization;

   375

  return NULL;

   376

}

   377

   378

/***************************************/

   379

/* B.3 - Language ST (Structured Text) */

   380

/***************************************/

   381

/***********************/

   382

/* B 3.1 - Expressions */

   383

/***********************/

   384

void *visit(or_expression_c *symbol) {

   385

  symbol_c *left_type = search_expression_type->get_type(symbol->l_exp);

   386

  symbol_c *right_type = search_expression_type->get_type(symbol->r_exp);

   387

  if (!search_expression_type->is_same_type(left_type, right_type))

   388

      ERROR;

   389

  if (search_expression_type->is_bool_type(left_type))

   390

    return print_binary_expression(symbol->l_exp, symbol->r_exp, " || ");

   391

  if (search_expression_type->is_binary_type(left_type))

   392

    return print_binary_expression(symbol->l_exp, symbol->r_exp, " | ");

   393

  ERROR;

   394

  return NULL;

   395

}

   396

   397

void *visit(xor_expression_c *symbol) {

   398

  symbol_c *left_type = search_expression_type->get_type(symbol->l_exp);

   399

  symbol_c *right_type = search_expression_type->get_type(symbol->r_exp);

   400

  if (!search_expression_type->is_same_type(left_type, right_type))

   401

      ERROR;

   402

  if (search_expression_type->is_bool_type(left_type)) {

   403

    s4o.print("(");

   404

    symbol->l_exp->accept(*this);

   405

    s4o.print(" && !");

   406

    symbol->r_exp->accept(*this);

   407

    s4o.print(") || (!");

   408

    symbol->l_exp->accept(*this);

   409

    s4o.print(" && ");

   410

    symbol->r_exp->accept(*this);

   411

    s4o.print(")");

   412

    return NULL;

   413

  }

   414

  if (search_expression_type->is_binary_type(left_type))

   415

    return print_binary_expression(symbol->l_exp, symbol->r_exp, " ^ ");

   416

  ERROR;

   417

  return NULL;

   418

}

   419

   420

void *visit(and_expression_c *symbol) {

   421

  symbol_c *left_type = search_expression_type->get_type(symbol->l_exp);

   422

  symbol_c *right_type = search_expression_type->get_type(symbol->r_exp);

   423

  if (!search_expression_type->is_same_type(left_type, right_type))

   424

      ERROR;

   425

  if (search_expression_type->is_bool_type(left_type))

   426

    return print_binary_expression(symbol->l_exp, symbol->r_exp, " && ");

   427

  if (search_expression_type->is_binary_type(left_type))

   428

    return print_binary_expression(symbol->l_exp, symbol->r_exp, " & ");

   429

  ERROR;

   430

  return NULL;

   431

}

   432

   433

void *visit(equ_expression_c *symbol) {

   434

  symbol_c *left_type = search_expression_type->get_type(symbol->l_exp);

   435

  symbol_c *right_type = search_expression_type->get_type(symbol->r_exp);

   436

  if (!search_expression_type->is_same_type(left_type, right_type))

   437

      ERROR;

   438

  if (search_expression_type->is_time_type(left_type) ||

   439

      search_expression_type->is_string_type(left_type))

   441

  return print_binary_expression(symbol->l_exp, symbol->r_exp, " == ");

   442

}

   443

   444

void *visit(notequ_expression_c *symbol) {

   445

  symbol_c *left_type = search_expression_type->get_type(symbol->l_exp);

   446

  symbol_c *right_type = search_expression_type->get_type(symbol->r_exp);

   447

  if (!search_expression_type->is_same_type(left_type, right_type))

   448

      ERROR;

   449

  if (search_expression_type->is_time_type(left_type) ||

   450

      search_expression_type->is_string_type(left_type))

   452

  return print_binary_expression(symbol->l_exp, symbol->r_exp, " != ");

   453

}

   454

   455

void *visit(lt_expression_c *symbol) {

   456

  symbol_c *left_type = search_expression_type->get_type(symbol->l_exp);

   457

  symbol_c *right_type = search_expression_type->get_type(symbol->r_exp);

   458

  if (!search_expression_type->is_same_type(left_type, right_type))

   459

      ERROR;

   460

  if (search_expression_type->is_time_type(left_type) ||

   461

      search_expression_type->is_string_type(left_type))

   463

  if (!search_base_type.type_is_enumerated(left_type))

   464

    return print_binary_expression(symbol->l_exp, symbol->r_exp, " < ");

   465

  ERROR;

   466

  return NULL;

   467

}

   468

   469

void *visit(gt_expression_c *symbol) {

   470

  symbol_c *left_type = search_expression_type->get_type(symbol->l_exp);

   471

  symbol_c *right_type = search_expression_type->get_type(symbol->r_exp);

   472

  if (!search_expression_type->is_same_type(left_type, right_type))

   473

      ERROR;

   474

  if (search_expression_type->is_time_type(left_type) ||

   475

      search_expression_type->is_string_type(left_type))

   477

  if (!search_base_type.type_is_enumerated(left_type))

   478

    return print_binary_expression(symbol->l_exp, symbol->r_exp, " > ");

   479

  ERROR;

   480

  return NULL;

   481

}

   482

   483

void *visit(le_expression_c *symbol) {

   484

  symbol_c *left_type = search_expression_type->get_type(symbol->l_exp);

   485

  symbol_c *right_type = search_expression_type->get_type(symbol->r_exp);

   486

  if (!search_expression_type->is_same_type(left_type, right_type))

   487

      ERROR;

   488

  if (search_expression_type->is_time_type(left_type) ||

   489

      search_expression_type->is_string_type(left_type))

   491

  if (!search_base_type.type_is_enumerated(left_type))

   492

    return print_binary_expression(symbol->l_exp, symbol->r_exp, " <= ");

   493

  ERROR;

   494

  return NULL;

   495

}

   496

   497

void *visit(ge_expression_c *symbol) {

   498

  symbol_c *left_type = search_expression_type->get_type(symbol->l_exp);

   499

  symbol_c *right_type = search_expression_type->get_type(symbol->r_exp);

   500

  if (!search_expression_type->is_same_type(left_type, right_type))

   501

      ERROR;