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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

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

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 *  (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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 *

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 */

    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

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 * code.

    35

 */

    36

    37

    38

    39

#include "../../util/strdup.hh"

    40

    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,

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      complextype_base_vg,

    54

      complextype_suffix_vg,

    55

      fparam_output_vg

    56

    } variablegeneration_t;

    57

    58

    typedef enum {

    59

      single_cg,

    60

      subrange_cg,

    61

      none_cg

    62

    } casegeneration_t;

    63

    64

  private:

    65

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

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     * by searching through the declarations of the variables currently

    67

     * in scope.

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     * This class does just that...

    69

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

    70

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

    71

     * This object instance will then later be called while the

    72

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

    73

     *

    74

     * Note that functions cannot contain calls to function blocks,

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     * so we do not create an object instance when handling

    76

     * a function declaration.

    77

     */

    78

    search_fb_instance_decl_c *search_fb_instance_decl;

    79

    80

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

    81

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

    82

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

    83

     * or function currently being processed.

    84

     * The following object does just that...

    85

     * This object instance will then later be called while the

    86

     * remaining st code is being handled.

    87

     */

    88

    search_expression_type_c *search_expression_type;

    89

    90

    search_varfb_instance_type_c *search_varfb_instance_type;

    91

    92

    search_base_type_c search_base_type;

    93

    94

    symbol_c* current_array_type;

    95

    symbol_c* current_param_type;

    96

    97

    int fcall_number;

    98

    symbol_c *fbname;

    99

   100

    bool first_subrange_case_list;

   101

   102

    variablegeneration_t wanted_variablegeneration;

   103

    casegeneration_t wanted_casegeneration;

   104

   105

  public:

   106

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

   107

    : generate_c_typedecl_c(s4o_ptr) {

   108

      search_fb_instance_decl = new search_fb_instance_decl_c(scope);

   109

      search_expression_type = new search_expression_type_c(scope);

   110

      search_varfb_instance_type = new search_varfb_instance_type_c(scope);

   111

      this->set_variable_prefix(variable_prefix);

   112

      current_array_type = NULL;

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      current_param_type = NULL;

   114

      fcall_number = 0;

   115

      fbname = name;

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      wanted_variablegeneration = expression_vg;

   117

      wanted_casegeneration = none_cg;

   118

    }

   119

   120

    virtual ~generate_c_st_c(void) {

   121

      delete search_fb_instance_decl;

   122

      delete search_expression_type;

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      delete search_varfb_instance_type;

   124

    }

   125

   126

   127

  public:

   128

    void generate(statement_list_c *stl) {

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      stl->accept(*this);

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    }

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   132

  private:

   133

   134

void *print_getter(symbol_c *symbol) {

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

   136

  if (wanted_variablegeneration == fparam_output_vg) {

   137

  	if (vartype == search_var_instance_decl_c::external_vt)

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      s4o.print(GET_EXTERNAL_BY_REF);

   139

    else if (vartype == search_var_instance_decl_c::located_vt)

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      s4o.print(GET_LOCATED_BY_REF);

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    else

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      s4o.print(GET_VAR_BY_REF);

   143

  }

   144

  else {

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	if (vartype == search_var_instance_decl_c::external_vt)

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	  s4o.print(GET_EXTERNAL);

   147

	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);

   151

  }

   152

  s4o.print("(");

   153

   154

  variablegeneration_t old_wanted_variablegeneration = wanted_variablegeneration;

   155

  wanted_variablegeneration = complextype_base_vg;

   156

  symbol->accept(*this);

   157

  if (search_varfb_instance_type->type_is_complex())

   158

    s4o.print(",");

   159

  wanted_variablegeneration = complextype_suffix_vg;

   160

  symbol->accept(*this);

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  s4o.print(")");

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  wanted_variablegeneration = old_wanted_variablegeneration;

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  return NULL;

   164

}

   165

   166

void *print_setter(symbol_c* symbol,

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		symbol_c* type,

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		symbol_c* value,

   169

		symbol_c* fb_symbol = NULL,

   170

		symbol_c* fb_value = NULL) {

   171

   172

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

   173

  if (vartype == search_var_instance_decl_c::external_vt) {

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

   175

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

   176

    if (variable != NULL) {

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      s4o.print(SET_EXTERNAL);

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      s4o.print("(");

   179

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

   180

      s4o.print(",");

   181

    }

   182

    else {

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      s4o.print(SET_COMPLEX_EXTERNAL);

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      s4o.print("(");

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    }

   186

  }

   187

  else {

   188

    if (vartype == search_var_instance_decl_c::located_vt)

   189

      s4o.print(SET_LOCATED);

   190

    else

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      s4o.print(SET_VAR);

   192

    s4o.print("(");

   193

  }

   194

   195

  if (fb_symbol != NULL) {

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    print_variable_prefix();

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    fb_symbol->accept(*this);

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    s4o.print(".");

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  }

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  else

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    wanted_variablegeneration = complextype_base_vg;

   202

   203

  symbol->accept(*this);

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  s4o.print(",");

   205

  wanted_variablegeneration = expression_vg;

   206

  print_check_function(type, value, fb_value);

   207

  /* 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.

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

   210

   * the correct value regarding our 'symbol'.

   211

   */

   212

  search_varfb_instance_type->get_vartype(symbol);

   213

  if (search_varfb_instance_type->type_is_complex()) {

   214

    s4o.print(",");

   215

    wanted_variablegeneration = complextype_suffix_vg;

   216

    symbol->accept(*this);

   217

  }

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  s4o.print(")");

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  wanted_variablegeneration = expression_vg;

   220

  return NULL;

   221

}

   222

   223

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

   224

/* B 1.3.3 - Derived data types */

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

   226

/*  signed_integer DOTDOT signed_integer */

   227

void *visit(subrange_c *symbol) {

   228

  switch (wanted_casegeneration) {

   229

    case subrange_cg:

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      s4o.print("case_expression >= ");

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

   232

      s4o.print(" && case_expression <= ");

   233

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

   234

      break;

   235

    default:

   236

      break;

   237

  }

   238

  return NULL;

   239

}

   240

   241

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

   242

/* B 1.4 - Variables */

   243

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

   244

void *visit(symbolic_variable_c *symbol) {

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  unsigned int vartype;

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  if (wanted_variablegeneration == complextype_base_vg)

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         generate_c_base_c::visit(symbol);

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  else if (wanted_variablegeneration == complextype_suffix_vg)

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         return NULL;

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  else if (this->is_variable_prefix_null()) {

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         vartype = search_varfb_instance_type->get_vartype(symbol);

   252

         if (wanted_variablegeneration == fparam_output_vg) {

   253

           s4o.print("&(");

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           generate_c_base_c::visit(symbol);

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           s4o.print(")");

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         } 

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         else {

   258

           generate_c_base_c::visit(symbol);

   259

         }

   260

  }

   261

  else

   262

      print_getter(symbol);

   263

  return NULL;

   264

}

   265

   266

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

   267

/* B.1.4.1   Directly Represented Variables */

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

   269

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

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void *visit(direct_variable_c *symbol) {

   271

  TRACE("direct_variable_c");

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

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

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  if (this->is_variable_prefix_null()) {

   275

    if (wanted_variablegeneration != fparam_output_vg)

   276

	  s4o.print("*(");

   277

  }

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  else {

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    switch (wanted_variablegeneration) {

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      case expression_vg:

   281

  	    s4o.print(GET_LOCATED);

   282

  	    s4o.print("(");

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  	    break;

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      case fparam_output_vg:

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        s4o.print(GET_LOCATED_BY_REF);

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        s4o.print("(");

   287

        break;

   288

      default:

   289

        break;

   290

    }

   291

  }

   292

  this->print_variable_prefix();

   293

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

   294

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

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	  wanted_variablegeneration != assignment_vg)

   296

    s4o.print(")");

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  return NULL;

   298

}

   299

   300

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

   301

/* B.1.4.2   Multi-element Variables */

   302

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

   303

   304

// SYM_REF2(structured_variable_c, record_variable, field_selector)

   305

void *visit(structured_variable_c *symbol) {

   306

  TRACE("structured_variable_c");

   307

  switch (wanted_variablegeneration) {

   308

    case complextype_base_vg:

   309

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

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      break;

   311

    case complextype_suffix_vg:

   312

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

   313

      s4o.print(".");

   314

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

   315

      break;

   316

    default:

   317

      if (this->is_variable_prefix_null()) {

   318

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

   319

    	s4o.print(".");

   320

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

   321

      }

   322

      else

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    	print_getter(symbol);

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      break;

   325

  }

   326

  return NULL;

   327

}

   328

   329

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

   330

//SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

   331

void *visit(array_variable_c *symbol) {

   332

  switch (wanted_variablegeneration) {

   333

    case complextype_base_vg:

   334

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

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      break;

   336

    case complextype_suffix_vg:

   337

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

   338

   339

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

   340

      if (current_array_type == NULL) ERROR;

   341

   342

      s4o.print(".table");

   343

      wanted_variablegeneration = expression_vg;

   344

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

   345

      wanted_variablegeneration = complextype_suffix_vg;

   346

   347

      current_array_type = NULL;

   348

      break;

   349

    default:

   350

      if (this->is_variable_prefix_null()) {

   351

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

   352

   353

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

   354

    	if (current_array_type == NULL) ERROR;

   355

   356

    	s4o.print(".table");

   357

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

   358

   359

        current_array_type = NULL;

   360

      }

   361

      else

   362

    	print_getter(symbol);

   363

      break;

   364

  }

   365

  return NULL;

   366

}

   367

   368

/* subscript_list ',' subscript */

   369

void *visit(subscript_list_c *symbol) {

   370

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

   371

    s4o.print("[__");

   372

    current_array_type->accept(*this);

   373

    s4o.print("_TRANSIDX(");

   374

    print_integer(i);

   375

    s4o.print(",");

   376

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

   377

    s4o.print(")]");

   378

  }

   379

  return NULL;

   380

}

   381

   382

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

   383

/* B 1.4.3 - Declaration & Initialisation */

   384

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

   385

   386

/* helper symbol for structure_initialization */

   387

/* structure_element_initialization_list ',' structure_element_initialization */

   388

void *visit(structure_element_initialization_list_c *symbol) {

   389

  generate_c_structure_initialization_c *structure_initialization = new generate_c_structure_initialization_c(&s4o);

   390

  structure_initialization->init_structure_default(this->current_param_type);

   391

  structure_initialization->init_structure_values(symbol);

   392

  delete structure_initialization;

   393

  return NULL;

   394

}

   395

   396

/* helper symbol for array_initialization */

   397

/* array_initial_elements_list ',' array_initial_elements */

   398

void *visit(array_initial_elements_list_c *symbol) {

   399

  generate_c_array_initialization_c *array_initialization = new generate_c_array_initialization_c(&s4o);

   400

  array_initialization->init_array_size(this->current_param_type);

   401

  array_initialization->init_array_values(symbol);

   402

  delete array_initialization;

   403

  return NULL;

   404

}

   405

   406

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

   407

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

   408

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

   409

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

   410

/* B 3.1 - Expressions */

   411

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

   412

void *visit(or_expression_c *symbol) {

   413

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

   414

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

   415

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

   416

      ERROR;

   417

  if (search_expression_type->is_bool_type(left_type))

   418

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

   419

  if (search_expression_type->is_binary_type(left_type))

   420

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

   421

  ERROR;

   422

  return NULL;

   423

}

   424

   425

void *visit(xor_expression_c *symbol) {

   426

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

   427

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

   428

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

   429

      ERROR;

   430

  if (search_expression_type->is_bool_type(left_type)) {

   431

    s4o.print("(");

   432

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

   433

    s4o.print(" && !");

   434

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

   435

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

   436

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

   437

    s4o.print(" && ");

   438

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

   439

    s4o.print(")");

   440

    return NULL;

   441

  }

   442

  if (search_expression_type->is_binary_type(left_type))

   443

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

   444

  ERROR;

   445

  return NULL;

   446

}

   447

   448

void *visit(and_expression_c *symbol) {

   449

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

   450

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

   451

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

   452

      ERROR;

   453

  if (search_expression_type->is_bool_type(left_type))

   454

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

   455

  if (search_expression_type->is_binary_type(left_type))

   456

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

   457

  ERROR;

   458

  return NULL;

   459

}

   460

   461

void *visit(equ_expression_c *symbol) {

   462

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

   463

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

   464

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

   465

      ERROR;

   466

  if (search_expression_type->is_time_type(left_type) ||

   467

      search_expression_type->is_string_type(left_type))

   468

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

   469

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

   470

}

   471

   472

void *visit(notequ_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("NE_", left_type, symbol->l_exp, symbol->r_exp);

   480

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

   481

}

   482

   483

void *visit(lt_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))

   490

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

   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(gt_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))