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/*

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

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 *

     4

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

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

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 *

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

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 *  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.

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 *

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

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

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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

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 *  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

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

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 *

    26

 */

    27

    28

    29

/*

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

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 *

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 * This is part of the 4th stage that generates

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

    34

 * code.

    35

 */

    36

    37

    38

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

    39

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

    40

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

    41

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

    42

    43

    44

class generate_c_st_c: public generate_c_typedecl_c {

    45

    46

  public:

    47

    typedef enum {

    48

      expression_vg,

    49

      assignment_vg,

    50

      complextype_base_vg,

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      complextype_suffix_vg,

    52

      fparam_output_vg

    53

    } variablegeneration_t;

    54

    55

  private:

    56

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

    57

     * by searching through the declarations of the variables currently

    58

     * in scope.

    59

     * This class does just that...

    60

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

    61

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

    62

     * This object instance will then later be called while the

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

    64

     *

    65

     * Note that functions cannot contain calls to function blocks,

    66

     * so we do not create an object instance when handling

    67

     * a function declaration.

    68

     */

    69

    search_fb_instance_decl_c *search_fb_instance_decl;

    70

    71

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

    72

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

    73

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

    74

     * or function currently being processed.

    75

     * The following object does just that...

    76

     * This object instance will then later be called while the

    77

     * remaining st code is being handled.

    78

     */

    79

    search_expression_type_c *search_expression_type;

    80

    81

    search_varfb_instance_type_c *search_varfb_instance_type;

    82

    83

    search_base_type_c search_base_type;

    84

    85

    symbol_c* current_array_type;

    86

    symbol_c* current_param_type;

    87

    88

    int fcall_number;

    89

    symbol_c *fbname;

    90

    91

    variablegeneration_t wanted_variablegeneration;

    92

    93

  public:

    94

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

    95

    : generate_c_typedecl_c(s4o_ptr) {

    96

      search_fb_instance_decl = new search_fb_instance_decl_c(scope);

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      search_expression_type = new search_expression_type_c(scope);

    98

      search_varfb_instance_type = new search_varfb_instance_type_c(scope);

    99

      this->set_variable_prefix(variable_prefix);

   100

      current_array_type = NULL;

   101

      current_param_type = NULL;

   102

      fcall_number = 0;

   103

      fbname = name;

   104

      wanted_variablegeneration = expression_vg;

   105

    }

   106

   107

    virtual ~generate_c_st_c(void) {

   108

      delete search_fb_instance_decl;

   109

      delete search_expression_type;

   110

      delete search_varfb_instance_type;

   111

    }

   112

   113

   114

  public:

   115

    void generate(statement_list_c *stl) {

   116

      stl->accept(*this);

   117

    }

   118

   119

  private:

   120

   121

void *print_getter(symbol_c *symbol) {

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

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  if (wanted_variablegeneration == fparam_output_vg) {

   124

  	if (vartype == search_var_instance_decl_c::external_vt)

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      s4o.print(GET_EXTERNAL_BY_REF);

   126

    else if (vartype == search_var_instance_decl_c::located_vt)

   127

      s4o.print(GET_LOCATED_BY_REF);

   128

    else

   129

      s4o.print(GET_VAR_BY_REF);

   130

  }

   131

  else {

   132

	if (vartype == search_var_instance_decl_c::external_vt)

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	  s4o.print(GET_EXTERNAL);

   134

	else if (vartype == search_var_instance_decl_c::located_vt)

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	  s4o.print(GET_LOCATED);

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	else

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	  s4o.print(GET_VAR);

   138

  }

   139

  s4o.print("(");

   140

   141

  variablegeneration_t old_wanted_variablegeneration = wanted_variablegeneration;

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  wanted_variablegeneration = complextype_base_vg;

   143

  symbol->accept(*this);

   144

  if (search_varfb_instance_type->type_is_complex())

   145

    s4o.print(",");

   146

  wanted_variablegeneration = complextype_suffix_vg;

   147

  symbol->accept(*this);

   148

  s4o.print(")");

   149

  wanted_variablegeneration = old_wanted_variablegeneration;

   150

  return NULL;

   151

}

   152

   153

void *print_setter(symbol_c* symbol,

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		symbol_c* type,

   155

		symbol_c* value,

   156

		symbol_c* fb_symbol = NULL,

   157

		symbol_c* fb_value = NULL) {

   158

   159

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

   160

  if (vartype == search_var_instance_decl_c::external_vt) {

   161

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

   162

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

   163

    if (variable != NULL) {

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      s4o.print(SET_EXTERNAL);

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      s4o.print("(");

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

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      s4o.print(",");

   168

    }

   169

    else {

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      s4o.print(SET_COMPLEX_EXTERNAL);

   171

      s4o.print("(");

   172

    }

   173

  }

   174

  else {

   175

    if (vartype == search_var_instance_decl_c::located_vt)

   176

      s4o.print(SET_LOCATED);

   177

    else

   178

      s4o.print(SET_VAR);

   179

    s4o.print("(");

   180

  }

   181

   182

  if (fb_symbol != NULL) {

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    print_variable_prefix();

   184

    fb_symbol->accept(*this);

   185

    s4o.print(".");

   186

  }

   187

  else

   188

    wanted_variablegeneration = complextype_base_vg;

   189

   190

  symbol->accept(*this);

   191

  s4o.print(",");

   192

  wanted_variablegeneration = expression_vg;

   193

  print_check_function(type, value, fb_value);

   194

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

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

   196

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

   197

   * the correct value regarding our 'symbol'.

   198

   */

   199

  search_varfb_instance_type->get_vartype(symbol);

   200

  if (search_varfb_instance_type->type_is_complex()) {

   201

    s4o.print(",");

   202

    wanted_variablegeneration = complextype_suffix_vg;

   203

    symbol->accept(*this);

   204

  }

   205

  s4o.print(")");

   206

  wanted_variablegeneration = expression_vg;

   207

  return NULL;

   208

}

   209

   210

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

   211

/* B 1.4 - Variables */

   212

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

   213

void *visit(symbolic_variable_c *symbol) {

   214

  unsigned int vartype;

   215

  if (wanted_variablegeneration == complextype_base_vg)

   216

         generate_c_base_c::visit(symbol);

   217

  else if (wanted_variablegeneration == complextype_suffix_vg)

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         return NULL;

   219

  else if (this->is_variable_prefix_null()) {

   220

         vartype = search_varfb_instance_type->get_vartype(symbol);

   221

         if (wanted_variablegeneration == fparam_output_vg) {

   222

           s4o.print("&(");

   223

           generate_c_base_c::visit(symbol);

   224

           s4o.print(")");

   225

         } 

   226

         else {

   227

           generate_c_base_c::visit(symbol);

   228

         }

   229

  }

   230

  else

   231

      print_getter(symbol);

   232

  return NULL;

   233

}

   234

   235

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

   236

/* B.1.4.1   Directly Represented Variables */

   237

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

   238

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

   239

void *visit(direct_variable_c *symbol) {

   240

  TRACE("direct_variable_c");

   241

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

   242

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

   243

  if (this->is_variable_prefix_null()) {

   244

    if (wanted_variablegeneration != fparam_output_vg)

   245

	  s4o.print("*(");

   246

  }

   247

  else {

   248

    switch (wanted_variablegeneration) {

   249

      case expression_vg:

   250

  	    s4o.print(GET_LOCATED);

   251

  	    s4o.print("(");

   252

  	    break;

   253

      case fparam_output_vg:

   254

        s4o.print(GET_LOCATED_BY_REF);

   255

        s4o.print("(");

   256

        break;

   257

      default:

   258

        break;

   259

    }

   260

  }

   261

  this->print_variable_prefix();

   262

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

   263

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

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	  wanted_variablegeneration != assignment_vg)

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    s4o.print(")");

   266

  return NULL;

   267

}

   268

   269

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

   270

/* B.1.4.2   Multi-element Variables */

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

   272

   273

// SYM_REF2(structured_variable_c, record_variable, field_selector)

   274

void *visit(structured_variable_c *symbol) {

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  TRACE("structured_variable_c");

   276

  switch (wanted_variablegeneration) {

   277

    case complextype_base_vg:

   278

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

   279

      break;

   280

    case complextype_suffix_vg:

   281

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

   282

      s4o.print(".");

   283

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

   284

      break;

   285

    default:

   286

      if (this->is_variable_prefix_null()) {

   287

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

   288

    	s4o.print(".");

   289

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

   290

      }

   291

      else

   292

    	print_getter(symbol);

   293

      break;

   294

  }

   295

  return NULL;

   296

}

   297

   298

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

   299

//SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

   300

void *visit(array_variable_c *symbol) {

   301

  switch (wanted_variablegeneration) {

   302

    case complextype_base_vg:

   303

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

   304

      break;

   305

    case complextype_suffix_vg:

   306

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

   307

   308

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

   309

      if (current_array_type == NULL) ERROR;

   310

   311

      s4o.print(".table");

   312

      wanted_variablegeneration = expression_vg;

   313

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

   314

      wanted_variablegeneration = complextype_suffix_vg;

   315

   316

      current_array_type = NULL;

   317

      break;

   318

    default:

   319

      if (this->is_variable_prefix_null()) {

   320

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

   321

   322

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

   323

    	if (current_array_type == NULL) ERROR;

   324

   325

    	s4o.print(".table");

   326

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

   327

   328

        current_array_type = NULL;

   329

      }

   330

      else

   331

    	print_getter(symbol);

   332

      break;

   333

  }

   334

  return NULL;

   335

}

   336

   337

/* subscript_list ',' subscript */

   338

void *visit(subscript_list_c *symbol) {

   339

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

   340

    s4o.print("[__");

   341

    current_array_type->accept(*this);

   342

    s4o.print("_TRANSIDX(");

   343

    print_integer(i);

   344

    s4o.print(",");

   345

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

   346

    s4o.print(")]");

   347

  }

   348

  return NULL;

   349

}

   350

   351

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

   352

/* B 1.4.3 - Declaration & Initialisation */

   353

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

   354

   355

/* helper symbol for structure_initialization */

   356

/* structure_element_initialization_list ',' structure_element_initialization */

   357

void *visit(structure_element_initialization_list_c *symbol) {

   358

  generate_c_structure_initialization_c *structure_initialization = new generate_c_structure_initialization_c(&s4o);

   359

  structure_initialization->init_structure_default(this->current_param_type);

   360

  structure_initialization->init_structure_values(symbol);

   361

  delete structure_initialization;

   362

  return NULL;

   363

}

   364

   365

/* helper symbol for array_initialization */

   366

/* array_initial_elements_list ',' array_initial_elements */

   367

void *visit(array_initial_elements_list_c *symbol) {

   368

  generate_c_array_initialization_c *array_initialization = new generate_c_array_initialization_c(&s4o);

   369

  array_initialization->init_array_size(this->current_param_type);

   370

  array_initialization->init_array_values(symbol);

   371

  delete array_initialization;

   372

  return NULL;

   373

}

   374

   375

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

   376

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

   377

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

   378

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

   379

/* B 3.1 - Expressions */

   380

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

   381

void *visit(or_expression_c *symbol) {

   382

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

   383

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

   384

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

   385

      ERROR;

   386

  if (search_expression_type->is_bool_type(left_type))

   387

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

   388

  if (search_expression_type->is_binary_type(left_type))

   389

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

   390

  ERROR;

   391

  return NULL;

   392

}

   393

   394

void *visit(xor_expression_c *symbol) {

   395

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

   396

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

   397

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

   398

      ERROR;

   399

  if (search_expression_type->is_bool_type(left_type)) {

   400

    s4o.print("(");

   401

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

   402

    s4o.print(" && !");

   403

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

   404

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

   405

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

   406

    s4o.print(" && ");

   407

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

   408

    s4o.print(")");

   409

    return NULL;

   410

  }

   411

  if (search_expression_type->is_binary_type(left_type))

   412

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

   413

  ERROR;

   414

  return NULL;

   415

}

   416

   417

void *visit(and_expression_c *symbol) {

   418

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

   419

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

   420

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

   421

      ERROR;

   422

  if (search_expression_type->is_bool_type(left_type))

   423

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

   424

  if (search_expression_type->is_binary_type(left_type))

   425

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

   426

  ERROR;

   427

  return NULL;

   428

}

   429

   430

void *visit(equ_expression_c *symbol) {

   431

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

   432

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

   433

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

   434

      ERROR;

   435

  if (search_expression_type->is_time_type(left_type) ||

   436

      search_expression_type->is_string_type(left_type))

   437

    return print_compare_function("__eq_", left_type, symbol->l_exp, symbol->r_exp);

   438

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

   439

}

   440

   441

void *visit(notequ_expression_c *symbol) {

   442

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

   443

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

   444

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

   445

      ERROR;

   446

  if (search_expression_type->is_time_type(left_type) ||

   447

      search_expression_type->is_string_type(left_type))

   448

    return print_compare_function("__ne_", left_type, symbol->l_exp, symbol->r_exp);

   449

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

   450

}

   451

   452

void *visit(lt_expression_c *symbol) {

   453

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

   454

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

   455

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

   456

      ERROR;

   457

  if (search_expression_type->is_time_type(left_type) ||

   458

      search_expression_type->is_string_type(left_type))

   459

    return print_compare_function("__lt_", left_type, symbol->l_exp, symbol->r_exp);

   460

  if (!search_base_type.type_is_enumerated(left_type))

   461

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

   462

  ERROR;

   463

  return NULL;

   464

}

   465

   466

void *visit(gt_expression_c *symbol) {

   467

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

   468

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

   469

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

   470

      ERROR;

   471

  if (search_expression_type->is_time_type(left_type) ||

   472

      search_expression_type->is_string_type(left_type))

   473

    return print_compare_function("__gt_", left_type, symbol->l_exp, symbol->r_exp);

   474

  if (!search_base_type.type_is_enumerated(left_type))

   475

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

   476

  ERROR;

   477

  return NULL;

   478

}

   479

   480

void *visit(le_expression_c *symbol) {

   481

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

   482

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

   483

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

   484

      ERROR;

   485

  if (search_expression_type->is_time_type(left_type) ||

   486

      search_expression_type->is_string_type(left_type))

   487

    return print_compare_function("__le_", left_type, symbol->l_exp, symbol->r_exp);

   488

  if (!search_base_type.type_is_enumerated(left_type))

   489

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

   490

  ERROR;

   491

  return NULL;

   492

}

   493

   494

void *visit(ge_expression_c *symbol) {

   495

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

   496

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

   497

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

   498

      ERROR;

   499

  if (search_expression_type->is_time_type(left_type) ||

   500

      search_expression_type->is_string_type(left_type))

   501

    return print_compare_function("__ge_", left_type, symbol->l_exp, symbol->r_exp);

   502