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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.

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 *

    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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 *

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 */

    27

    28

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/*

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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

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 * code.

    35

 */

    36

    37

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

    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,

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      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.

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     *

    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;

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    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) {

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      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

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      s4o.print(GET_VAR_BY_REF);

   130

  }

   131

  else {

   132

	if (vartype == search_var_instance_decl_c::external_vt)

   133

	  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;

   142

  wanted_variablegeneration = complextype_base_vg;

   143

  symbol->accept(*this);

   144

  if (search_varfb_instance_type->type_is_complex())

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    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

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

   159

  if (vartype == search_var_instance_decl_c::external_vt) {

   160

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

   161

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

   162

    if (variable != NULL) {

   163

      s4o.print(SET_EXTERNAL);

   164

      s4o.print("(");

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

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      s4o.print(",");

   167

    }

   168

    else {

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      s4o.print(SET_COMPLEX_EXTERNAL);

   170

      s4o.print("(");

   171

    }

   172

  }

   173

  else {

   174

    if (vartype == search_var_instance_decl_c::located_vt)

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      s4o.print(SET_LOCATED);

   176

    else

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      s4o.print(SET_VAR);

   178

    s4o.print("(");

   179

  }

   180

   181

  if (fb_symbol != NULL) {

   182

    print_variable_prefix();

   183

    fb_symbol->accept(*this);

   184

    s4o.print(".");

   185

  }

   186

  else

   187

    wanted_variablegeneration = complextype_base_vg;

   188

  symbol->accept(*this);

   189

  s4o.print(",");

   190

  wanted_variablegeneration = expression_vg;

   191

  print_check_function(type, value, fb_value);

   192

  if (search_varfb_instance_type->type_is_complex()) {

   193

    s4o.print(",");

   194

    wanted_variablegeneration = complextype_suffix_vg;

   195

    symbol->accept(*this);

   196

  }

   197

  s4o.print(")");

   198

  wanted_variablegeneration = expression_vg;

   199

  return NULL;

   200

}

   201

   202

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

   203

/* B 1.4 - Variables */

   204

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

   205

void *visit(symbolic_variable_c *symbol) {

   206

  unsigned int vartype;

   207

  if (wanted_variablegeneration == complextype_base_vg)

   208

         generate_c_base_c::visit(symbol);

   209

  else if (wanted_variablegeneration == complextype_suffix_vg)

   210

         return NULL;

   211

  else if (this->is_variable_prefix_null()) {

   212

         vartype = search_varfb_instance_type->get_vartype(symbol);

   213

         if (wanted_variablegeneration == fparam_output_vg) {

   214

           s4o.print("&(");

   215

           generate_c_base_c::visit(symbol);

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           s4o.print(")");

   217

         } 

   218

         else {

   219

           generate_c_base_c::visit(symbol);

   220

         }

   221

  }

   222

  else

   223

      print_getter(symbol);

   224

  return NULL;

   225

}

   226

   227

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

   228

/* B.1.4.1   Directly Represented Variables */

   229

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

   230

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

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void *visit(direct_variable_c *symbol) {

   232

  TRACE("direct_variable_c");

   233

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

   234

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

   235

  if (this->is_variable_prefix_null()) {

   236

    if (wanted_variablegeneration != fparam_output_vg)

   237

	  s4o.print("*(");

   238

  }

   239

  else {

   240

    switch (wanted_variablegeneration) {

   241

      case expression_vg:

   242

  	    s4o.print(GET_LOCATED);

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  	    s4o.print("(");

   244

  	    break;

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      case fparam_output_vg:

   246

        s4o.print(GET_LOCATED_BY_REF);

   247

        s4o.print("(");

   248

        break;

   249

      default:

   250

        break;

   251

    }

   252

  }

   253

  this->print_variable_prefix();

   254

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

   255

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

   256

	  wanted_variablegeneration != assignment_vg)

   257

    s4o.print(")");

   258

  return NULL;

   259

}

   260

   261

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

   262

/* B.1.4.2   Multi-element Variables */

   263

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

   264

   265

// SYM_REF2(structured_variable_c, record_variable, field_selector)

   266

void *visit(structured_variable_c *symbol) {

   267

  TRACE("structured_variable_c");

   268

  switch (wanted_variablegeneration) {

   269

    case complextype_base_vg:

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

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      break;

   272

    case complextype_suffix_vg:

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

   274

      s4o.print(".");

   275

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

   276

      break;

   277

    default:

   278

      if (this->is_variable_prefix_null()) {

   279

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

   280

    	s4o.print(".");

   281

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

   282

      }

   283

      else

   284

    	print_getter(symbol);

   285

      break;

   286

  }

   287

  return NULL;

   288

}

   289

   290

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

   291

//SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

   292

void *visit(array_variable_c *symbol) {

   293

  switch (wanted_variablegeneration) {

   294

    case complextype_base_vg:

   295

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

   296

      break;

   297

    case complextype_suffix_vg:

   298

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

   299

   300

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

   301

      if (current_array_type == NULL) ERROR;

   302

   303

      s4o.print(".table");

   304

      wanted_variablegeneration = expression_vg;

   305

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

   306

      wanted_variablegeneration = complextype_suffix_vg;

   307

   308

      current_array_type = NULL;

   309

      break;

   310

    default:

   311

      if (this->is_variable_prefix_null()) {

   312

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

   313

   314

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

   315

    	if (current_array_type == NULL) ERROR;

   316

   317

    	s4o.print(".table");

   318

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

   319

   320

        current_array_type = NULL;

   321

      }

   322

      else

   323

    	print_getter(symbol);

   324

      break;

   325

  }

   326

  return NULL;

   327

}

   328

   329

/* subscript_list ',' subscript */

   330

void *visit(subscript_list_c *symbol) {

   331

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

   332

    s4o.print("[__");

   333

    current_array_type->accept(*this);

   334

    s4o.print("_TRANSIDX");

   335

    print_integer(i);

   336

    s4o.print("(");

   337

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

   338

    s4o.print(")]");

   339

  }

   340

  return NULL;

   341

}

   342

   343

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

   344

/* B 1.4.3 - Declaration & Initialisation */

   345

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

   346

   347

/* helper symbol for structure_initialization */

   348

/* structure_element_initialization_list ',' structure_element_initialization */

   349

void *visit(structure_element_initialization_list_c *symbol) {

   350

  generate_c_structure_initialization_c *structure_initialization = new generate_c_structure_initialization_c(&s4o);

   351

  structure_initialization->init_structure_default(this->current_param_type);

   352

  structure_initialization->init_structure_values(symbol);

   353

  delete structure_initialization;

   354

  return NULL;

   355

}

   356

   357

/* helper symbol for array_initialization */

   358

/* array_initial_elements_list ',' array_initial_elements */

   359

void *visit(array_initial_elements_list_c *symbol) {

   360

  generate_c_array_initialization_c *array_initialization = new generate_c_array_initialization_c(&s4o);

   361

  array_initialization->init_array_size(this->current_param_type);

   362

  array_initialization->init_array_values(symbol);

   363

  delete array_initialization;

   364

  return NULL;

   365

}

   366

   367

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

   368

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

   369

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

   370

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

   371

/* B 3.1 - Expressions */

   372

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

   373

void *visit(or_expression_c *symbol) {

   374

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

   375

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

   376

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

   377

      ERROR;

   378

  if (search_expression_type->is_bool_type(left_type))

   379

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

   380

  if (search_expression_type->is_binary_type(left_type))

   381

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

   382

  ERROR;

   383

  return NULL;

   384

}

   385

   386

void *visit(xor_expression_c *symbol) {

   387

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

   388

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

   389

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

   390

      ERROR;

   391

  if (search_expression_type->is_bool_type(left_type)) {

   392

    s4o.print("(");

   393

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

   394

    s4o.print(" && !");

   395

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

   396

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

   397

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

   398

    s4o.print(" && ");

   399

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

   400

    s4o.print(")");

   401

    return NULL;

   402

  }

   403

  if (search_expression_type->is_binary_type(left_type))

   404

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

   405

  ERROR;

   406

  return NULL;

   407

}

   408

   409

void *visit(and_expression_c *symbol) {

   410

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

   411

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

   412

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

   413

      ERROR;

   414

  if (search_expression_type->is_bool_type(left_type))

   415

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

   416

  if (search_expression_type->is_binary_type(left_type))

   417

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

   418

  ERROR;

   419

  return NULL;

   420

}

   421

   422

void *visit(equ_expression_c *symbol) {

   423

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

   424

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

   425

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

   426

      ERROR;

   427

  if (search_expression_type->is_time_type(left_type) ||

   428

      search_expression_type->is_string_type(left_type))

   429

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

   430

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

   431

}

   432

   433

void *visit(notequ_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))

   440

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

   441

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

   442

}

   443

   444

void *visit(lt_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))

   451

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

   452

  if (!search_base_type.type_is_enumerated(left_type))

   453

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

   454

  ERROR;

   455

  return NULL;

   456

}

   457

   458

void *visit(gt_expression_c *symbol) {

   459

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

   460

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

   461

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

   462

      ERROR;

   463

  if (search_expression_type->is_time_type(left_type) ||

   464

      search_expression_type->is_string_type(left_type))

   465

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

   466

  if (!search_base_type.type_is_enumerated(left_type))

   467

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

   468

  ERROR;

   469

  return NULL;

   470

}

   471

   472

void *visit(le_expression_c *symbol) {

   473

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

   474

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

   475

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

   476

      ERROR;

   477

  if (search_expression_type->is_time_type(left_type) ||

   478

      search_expression_type->is_string_type(left_type))

   479

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

   480

  if (!search_base_type.type_is_enumerated(left_type))

   481

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

   482

  ERROR;

   483

  return NULL;

   484

}

   485

   486

void *visit(ge_expression_c *symbol) {

   487

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

   488

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

   489

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

   490

      ERROR;

   491

  if (search_expression_type->is_time_type(left_type) ||

   492

      search_expression_type->is_string_type(left_type))

   493

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

   494

  if (!search_base_type.type_is_enumerated(left_type))

   495

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

   496

  ERROR;

   497

  return NULL;

   498

}

   499

   500

void *visit(add_expression_c *symbol) {

   501

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

   502

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

   503

	if ((typeid(*left_type) == typeid(time_type_name_c) && typeid(*right_type) == typeid(time_type_name_c)) ||