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/*

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 * (c) 2003 Mario de Sousa

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 *

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 * Offered to the public under the terms of the GNU General Public License

     5

 * as published by the Free Software Foundation; either version 2 of the

     6

 * License, or (at your option) any later version.

     7

 *

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

     9

 * WITHOUT ANY WARRANTY; without even the implied warranty of

    10

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General

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 * Public License for more details.

    12

 *

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

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

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 */

    16

    17

/*

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 * An IEC 61131-3 IL and ST compiler.

    19

 *

    20

 * 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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 */

    24

    25

    26

/* Determine the data type of an ST expression.

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 * A reference to the relevant type definition is returned.

    28

 *

    29

 * For example:

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 *       2 + 3       -> returns reference to a int_type_name_c object.

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 *       22.2 - 5    -> returns reference to a real_type_name_c object.

    32

 *       etc...

    33

 */

    34

    39

typedef enum {function_add,

    40

              function_sub,

    41

              function_and,

    42

              function_or,

    43

              function_sqrt,

    44

              function_none} function_type_t;

    45

    46

    47

function_type_t get_function_type(identifier_c *function_name) {

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  if (!strcasecmp(function_name->value, "ADD"))

    49

    return function_add;

    50

  else if (!strcasecmp(function_name->value, "SUB"))

    51

    return function_sub;

    52

  else if (!strcasecmp(function_name->value, "AND"))

    53

    return function_and;

    54

  else if (!strcasecmp(function_name->value, "OR"))

    55

    return function_or;

    56

  else if (!strcasecmp(function_name->value, "SQRT"))

    57

    return function_sqrt;

    58

  else return function_none;

    59

}

    61

    62

    63

symbol_c *generate_param_name(const char *name) {

    64

  symbol_c *param_name = new identifier_c(name);

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  return param_name;

    66

}

    67

    68

    69

symbol_c *generate_param_name(const char *format, int number) {

    70

  char name[10];

    71

  sprintf(name, format, number);

    72

  symbol_c *param_name = new identifier_c(name);

    73

  return param_name;

    74

}

    75

    76

    77

class search_expression_type_c: public search_constant_type_c {

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  private:

    79

    search_varfb_instance_type_c *search_varfb_instance_type;

    80

    search_base_type_c search_base_type;

    81

    82

  public:

    83

    search_expression_type_c(symbol_c *search_scope) {

    84

      search_varfb_instance_type = new search_varfb_instance_type_c(search_scope);

    85

    }

    86

    87

    virtual ~search_expression_type_c(void) {

    88

      delete search_varfb_instance_type;

    89

    }

    90

    91

    /* A helper function... */

    92

    bool is_bool_type(symbol_c *type_symbol) {

    93

      return (typeid(*type_symbol) == typeid(bool_type_name_c));

    94

    }

    95

    96

    /* A helper function... */

    97

    bool is_time_type(symbol_c *type_symbol) {

    98

      if (typeid(*type_symbol) == typeid(time_type_name_c)) {return true;}

    99

      if (typeid(*type_symbol) == typeid(date_type_name_c)) {return true;}

   100

      if (typeid(*type_symbol) == typeid(tod_type_name_c)) {return true;}

   101

      if (typeid(*type_symbol) == typeid(dt_type_name_c)) {return true;}

   102

      return false;

   103

    }

   104

   105

    /* A helper function... */

   106

    bool is_integer_type(symbol_c *type_symbol) {

   107

      if (typeid(*type_symbol) == typeid(sint_type_name_c)) {return true;}

   108

      if (typeid(*type_symbol) == typeid(int_type_name_c)) {return true;}

   109

      if (typeid(*type_symbol) == typeid(dint_type_name_c)) {return true;}

   110

      if (typeid(*type_symbol) == typeid(lint_type_name_c)) {return true;}

   111

      if (typeid(*type_symbol) == typeid(usint_type_name_c)) {return true;}

   112

      if (typeid(*type_symbol) == typeid(uint_type_name_c)) {return true;}

   113

      if (typeid(*type_symbol) == typeid(udint_type_name_c)) {return true;}

   114

      if (typeid(*type_symbol) == typeid(ulint_type_name_c)) {return true;}

   115

      if (typeid(*type_symbol) == typeid(constant_int_type_name_c)) {return true;}

   116

      return false;

   117

    }

   118

   119

    bool is_real_type(symbol_c *type_symbol) {

   120

      if (typeid(*type_symbol) == typeid(real_type_name_c)) {return true;}

   121

      if (typeid(*type_symbol) == typeid(lreal_type_name_c)) {return true;}

   122

      if (typeid(*type_symbol) == typeid(constant_real_type_name_c)) {return true;}

   123

      return false;

   124

    }

   125

   126

    bool is_num_type(symbol_c *type_symbol) {

   127

      return is_real_type(type_symbol) || is_integer_type(type_symbol);

   128

    }

   129

   130

    bool is_binary_type(symbol_c *type_symbol) {

   131

      if (typeid(*type_symbol) == typeid(bool_type_name_c)) {return true;}

   132

      if (typeid(*type_symbol) == typeid(byte_type_name_c)) {return true;}

   133

      if (typeid(*type_symbol) == typeid(word_type_name_c)) {return true;}

   134

      if (typeid(*type_symbol) == typeid(dword_type_name_c)) {return true;}

   135

      if (typeid(*type_symbol) == typeid(lword_type_name_c)) {return true;}

   136

      if (typeid(*type_symbol) == typeid(constant_int_type_name_c)) {return true;}

   137

      return false;

   138

    }

   139

   140

    bool is_same_type(symbol_c *first_type, symbol_c *second_type) {

   141

      if (typeid(*first_type) == typeid(*second_type)) {return true;}

   142

      if (is_integer_type(first_type) && (typeid(*second_type) == typeid(constant_int_type_name_c))) {return true;}

   143

      if ((typeid(*first_type) == typeid(constant_int_type_name_c) && is_integer_type(second_type))) {return true;}

   144

      if (is_binary_type(first_type) && (typeid(*second_type) == typeid(constant_int_type_name_c))) {return true;}

   145

      if ((typeid(*first_type) == typeid(constant_int_type_name_c) && is_binary_type(second_type))) {return true;}

   146

      if (is_real_type(first_type) && (typeid(*second_type) == typeid(constant_real_type_name_c))) {return true;}

   147

      if ((typeid(*first_type) == typeid(constant_real_type_name_c) && is_real_type(second_type))) {return true;}

   148

      return false;

   149

    }

   150

   151

    symbol_c* common_type(symbol_c *first_type, symbol_c *second_type) {

   152

      if (typeid(*first_type) == typeid(*second_type)) {return first_type;}

   153

      if (is_integer_type(first_type) && (typeid(*second_type) == typeid(constant_int_type_name_c))) {return first_type;}

   154

      if ((typeid(*first_type) == typeid(constant_int_type_name_c) && is_integer_type(second_type))) {return second_type;}

   155

      if (is_binary_type(first_type) && (typeid(*second_type) == typeid(constant_int_type_name_c))) {return first_type;}

   156

      if ((typeid(*first_type) == typeid(constant_int_type_name_c) && is_binary_type(second_type))) {return second_type;}

   157

      if (is_real_type(first_type) && (typeid(*second_type) == typeid(constant_real_type_name_c))) {return first_type;}

   158

      if ((typeid(*first_type) == typeid(constant_real_type_name_c) && is_real_type(second_type))) {return second_type;}

   159

      return NULL;

   160

    }

   161

   162

  private:

   163

   164

  void *compute_standard_function_st(function_invocation_c *symbol) {

   166

    symbol_c *current_type = NULL;

   167

    symbol_c *return_type = NULL;

   170

    function_type_t current_function_type = get_function_type((identifier_c *)symbol->function_name);

   171

    function_call_param_iterator_c function_call_param_iterator(symbol);

   176

    for(int current_param = 0; current_param < ((list_c *)symbol->parameter_assignment_list)->n; current_param++) {

   177

      symbol_c *param_name = NULL;

   178

      switch (current_function_type) {

   179

        case function_add:

   180

        case function_and:

   181

        case function_or:

   182

          param_name = generate_param_name("IN%d", current_param + 1);

   183

          break;

   184

        case function_sub:

   185

          if (current_param < 2)

   186

            param_name = generate_param_name("IN%d", current_param + 1);

   187

          else ERROR;

   188

          break;

   189

        default: ERROR;

   190

      }

   191

   192

      /* Get the value from a foo(<param_name> = <param_value>) style call */

   193

      symbol_c *param_value = function_call_param_iterator.search(param_name);

   194

      delete param_name;

   195

   196

      /* Get the value from a foo(<param_value>) style call */

   197

      if (param_value == NULL)

   198

        param_value = function_call_param_iterator.next();

   199

   200

      if (param_value == NULL) ERROR;

   201

   202

      symbol_c *param_type = (symbol_c *)param_value->accept(*this);

   203

   204

      switch (current_function_type) {

   205

        case function_add:

   206

          if (current_param == 0)

   207

            current_type = param_type;

   208

          else if (current_param == 1) {

   209

            if ((is_integer_type(current_type) && is_same_type(current_type, param_type)) ||

   210

                (is_real_type(current_type) && is_same_type(current_type, param_type))) {

   211

              current_type = common_type(current_type, param_type);

   212

              return_type = current_type;

   213

            }

   214

            else if (is_time_type(current_type)) {

   215

              if ((typeid(*current_type) == typeid(time_type_name_c)) && (typeid(*param_type) == typeid(time_type_name_c))) {return_type = (symbol_c *)&time_type_name;}

   216

              else if (typeid(*current_type) == typeid(tod_type_name_c) && typeid(*param_type) == typeid(time_type_name_c)) {return_type = (symbol_c *)&tod_type_name;}

   217

              else if (typeid(*current_type) == typeid(dt_type_name_c) && typeid(*param_type) == typeid(time_type_name_c)) {return_type = (symbol_c *)&dt_type_name;}

   218

              else ERROR;

   219

            }

   220

            else ERROR;

   221

          }

   222

          else if (!is_time_type(current_type) && is_same_type(current_type, param_type)) {

   223

            current_type = common_type(current_type, param_type);

   224

            return_type = current_type;

   225

          }

   226

          else ERROR;

   227

          break;

   228

        case function_sub:

   229

          if (current_param == 0)

   230

            current_type = param_type;

   231

          else if (current_param == 1) {

   232

            if ((is_integer_type(current_type) && is_same_type(current_type, param_type)) ||

   233

                (is_real_type(current_type) && is_same_type(current_type, param_type)))

   234

              return_type = common_type(current_type, param_type);

   235

            else if (is_time_type(current_type)) {

   236

              if (typeid(*current_type) == typeid(time_type_name_c) && typeid(*param_type) == typeid(time_type_name_c)) {return_type = (symbol_c *)&time_type_name;}

   237

              else if (typeid(*current_type) == typeid(date_type_name_c) && typeid(*param_type) == typeid(date_type_name_c)) {return_type = (symbol_c *)&time_type_name;}

   238

              else if (typeid(*current_type) == typeid(tod_type_name_c) && typeid(*param_type) == typeid(time_type_name_c)) {return_type = (symbol_c *)&tod_type_name;}

   239

              else if (typeid(*current_type) == typeid(tod_type_name_c) && typeid(*param_type) == typeid(tod_type_name_c)) {return_type = (symbol_c *)&time_type_name;}

   240

              else if (typeid(*current_type) == typeid(dt_type_name_c) && typeid(*param_type) == typeid(time_type_name_c)) {return_type = (symbol_c *)&dt_type_name;}

   241

              else if (typeid(*current_type) == typeid(dt_type_name_c) && typeid(*param_type) == typeid(dt_type_name_c)) {return_type = (symbol_c *)&time_type_name;}

   242

              else ERROR;

   243

            }

   244

            else ERROR;

   245

          }

   246

          else ERROR;

   247

          break;

   248

        case function_and:

   249

        case function_or:

   250

          if (current_param == 0)

   251

            if (is_binary_type(param_type))

   252

              current_type = param_type;

   253

            else ERROR;

   254

          else if (is_same_type(current_type, param_type))

   255

            return_type = common_type(current_type, param_type);

   256

          else ERROR;

   257

          break;

   258

        default: ERROR;

   259

      }

   260

    }

   261

    return (void *)return_type;

   264

  }

   265

   266

  public:

   267

   268

  void *compute_standard_function_il(il_function_call_c *symbol, symbol_c *param_type) {

   270

    symbol_c *return_type = NULL;

   271

    function_type_t current_function_type = get_function_type((identifier_c *)symbol->function_name);

   272

    if (current_function_type == function_none) ERROR;

   273

   274

    function_call_param_iterator_c function_call_param_iterator(symbol);

   275

   276

    int nb_param = 1;

   277

    if (symbol->il_operand_list != NULL)

   278

      nb_param += ((list_c *)symbol->il_operand_list)->n;

   279

   280

    for(int current_param = 0; current_param < nb_param; current_param++) {

   281

   282

      if (current_param != 0) {

   283

        symbol_c *param_name = NULL;

   284

        switch (current_function_type) {

   285

          default: ERROR;

   286

        }

   287

   288

        /* Get the value from a foo(<param_name> = <param_value>) style call */

   289

        symbol_c *param_value = function_call_param_iterator.search(param_name);

   290

        delete param_name;

   291

   292

        /* Get the value from a foo(<param_value>) style call */

   293

        if (param_value == NULL)

   294

          param_value = function_call_param_iterator.next();

   295

   296

        if (param_value == NULL) ERROR;

   297

   298

        param_type = (symbol_c *)param_value->accept(*this);

   299

      }

   300

   301

      switch (current_function_type) {

   302

        case function_sqrt:

   303

          if (current_param == 0 && is_real_type(param_type))

   304

            return_type = param_type;

   305

          else ERROR;

   306

          break;

   307

        default: ERROR;

   308

      }

   309

    }

   310

   311

    return (void *)return_type;

   312

  }

   313

   315

   316

  /* A helper function... */

   317

  void *compute_boolean_expression(symbol_c *left_type, symbol_c *right_type) {

   318

    if (!is_same_type(left_type, right_type))

   319

      ERROR;

   320

    if (!is_bool_type(left_type) && !is_binary_type(left_type))

   321

      ERROR;

   322

    if (typeid(*left_type) == typeid(constant_int_type_name_c)) {return (void *)right_type;}

   323

    else {return (void *)left_type;}

   324

  }

   325

   326

  /* A helper function... */

   327

  void *compute_numeric_expression(symbol_c *left_type, symbol_c *right_type) {

   328

    if (!is_same_type(left_type, right_type))

   329

      ERROR;

   330

    if (!is_integer_type(left_type) && !is_real_type(left_type))

   331

      ERROR;

   332

    if ((typeid(*left_type) == typeid(constant_int_type_name_c)) || (typeid(*left_type) == typeid(constant_real_type_name_c))) {return (void *)right_type;}

   333

    else {return (void *)left_type;}

   334

    return NULL;

   335

  }

   336

   337

  /* a helper function... */

   338

  symbol_c *base_type(symbol_c *symbol) {

   339

    return (symbol_c *)symbol->accept(search_base_type);

   340

  }

   341

   342

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

   343

/* B 1.4 - Variables */

   344

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

   345

   346

  void *visit(symbolic_variable_c *symbol) {

   347

    symbol_c *res;

   348

   349

    /* Nope, now we assume it is a variable, and determine its type... */

   350

    res = search_varfb_instance_type->get_type(symbol);

   351

    if (NULL != res) return res;

   352

   353

    return NULL;

   354

  }

   355

   356

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

   357

/* B 1.4.2 - Multi-element variables */

   358

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

   359

   360

  void *visit(array_variable_c *symbol) {

   361

    symbol_c *res;

   362

   363

    /* Nope, now we assume it is a variable, and determine its type... */

   364

    res = search_varfb_instance_type->get_type(symbol);

   365

    if (NULL != res) return res;

   366

   367

    return NULL;

   368

  }

   369

   370

  void *visit(structured_variable_c *symbol) {

   371

    symbol_c *res;

   372

   373

    /* Nope, now we assume it is a variable, and determine its type... */

   374

    res = search_varfb_instance_type->get_type(symbol);

   375

    if (NULL != res) return res;

   376

   377

    return NULL;

   378

  }

   379

   380

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

   381

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

   382

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

   383

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

   384

/* B 3.1 - Expressions */

   385

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

   386

  void *visit(or_expression_c *symbol) {

   387

    symbol_c *left_type = base_type((symbol_c *)symbol->l_exp->accept(*this));

   388

    symbol_c *right_type = base_type((symbol_c *)symbol->r_exp->accept(*this));

   389

    return compute_boolean_expression(left_type, right_type);

   390

  }

   391

   392

  void *visit(xor_expression_c *symbol) {

   393

    symbol_c *left_type = base_type((symbol_c *)symbol->l_exp->accept(*this));

   394

    symbol_c *right_type = base_type((symbol_c *)symbol->r_exp->accept(*this));

   395

    return compute_boolean_expression(left_type, right_type);

   396

  }

   397

   398

  void *visit(and_expression_c *symbol) {

   399

    symbol_c *left_type = base_type((symbol_c *)symbol->l_exp->accept(*this));

   400

    symbol_c *right_type = base_type((symbol_c *)symbol->r_exp->accept(*this));

   401

    return compute_boolean_expression(left_type, right_type); 

   402

  }

   403

   404

  void *visit(equ_expression_c *symbol) {return (void *)&bool_type_name;}

   405

  void *visit(notequ_expression_c *symbol) {return (void *)&bool_type_name;}

   406

  void *visit(lt_expression_c *symbol) {return (void *)&bool_type_name;}

   407

  void *visit(gt_expression_c *symbol) {return (void *)&bool_type_name;}

   408

  void *visit(le_expression_c *symbol) {return (void *)&bool_type_name;}

   409

  void *visit(ge_expression_c *symbol) {return (void *)&bool_type_name;}

   410

   411

  void *visit(add_expression_c *symbol) {

   412

    symbol_c *left_type = base_type((symbol_c *)symbol->l_exp->accept(*this));

   413

    symbol_c *right_type = base_type((symbol_c *)symbol->r_exp->accept(*this));

   414

    if (typeid(*left_type) == typeid(time_type_name_c) && typeid(*right_type) == typeid(time_type_name_c)) {return (void *)&time_type_name;}

   415

    if (typeid(*left_type) == typeid(tod_type_name_c) && typeid(*right_type) == typeid(time_type_name_c)) {return (void *)&tod_type_name;}

   416

    if (typeid(*left_type) == typeid(dt_type_name_c) && typeid(*right_type) == typeid(time_type_name_c)) {return (void *)&dt_type_name;}

   417

    return compute_numeric_expression(left_type, right_type);

   418

  }

   419

   420

  void *visit(sub_expression_c *symbol) {

   421

    symbol_c *left_type = base_type((symbol_c *)symbol->l_exp->accept(*this));

   422

    symbol_c *right_type = base_type((symbol_c *)symbol->r_exp->accept(*this));

   423

    if (typeid(*left_type) == typeid(time_type_name_c) && typeid(*right_type) == typeid(time_type_name_c)) {return (void *)&time_type_name;}

   424

    if (typeid(*left_type) == typeid(date_type_name_c) && typeid(*right_type) == typeid(date_type_name_c)) {return (void *)&time_type_name;}

   425

    if (typeid(*left_type) == typeid(tod_type_name_c) && typeid(*right_type) == typeid(time_type_name_c)) {return (void *)&tod_type_name;}

   426

    if (typeid(*left_type) == typeid(tod_type_name_c) && typeid(*right_type) == typeid(tod_type_name_c)) {return (void *)&time_type_name;}

   427

    if (typeid(*left_type) == typeid(dt_type_name_c) && typeid(*right_type) == typeid(time_type_name_c)) {return (void *)&dt_type_name;}

   428

    if (typeid(*left_type) == typeid(dt_type_name_c) && typeid(*right_type) == typeid(dt_type_name_c)) {return (void *)&time_type_name;}

   429

    return compute_numeric_expression(left_type, right_type);

   430

  }

   431

   432

  void *visit(mul_expression_c *symbol) {

   433

    symbol_c *left_type = base_type((symbol_c *)symbol->l_exp->accept(*this));

   434

    symbol_c *right_type = base_type((symbol_c *)symbol->r_exp->accept(*this));

   435

    if (typeid(*left_type) == typeid(time_type_name_c) && is_integer_type(right_type)) {return (void *)&time_type_name;}

   436

    if (typeid(*left_type) == typeid(time_type_name_c) && is_real_type(right_type)) {return (void *)&time_type_name;}

   437

    return compute_numeric_expression(left_type, right_type);

   438

  }

   439

   440

  void *visit(div_expression_c *symbol) {

   441

    symbol_c *left_type = base_type((symbol_c *)symbol->l_exp->accept(*this));

   442

    symbol_c *right_type = base_type((symbol_c *)symbol->r_exp->accept(*this));

   443

    if (typeid(*left_type) == typeid(time_type_name_c) && is_integer_type(right_type)) {return (void *)&time_type_name;}

   444

    if (typeid(*left_type) == typeid(time_type_name_c) && is_real_type(right_type)) {return (void *)&time_type_name;}

   445

    return compute_numeric_expression(left_type, right_type);

   446

  }

   447

   448

  void *visit(mod_expression_c *symbol) {

   449

    symbol_c *left_type = base_type((symbol_c *)symbol->l_exp->accept(*this));

   450

    symbol_c *right_type = base_type((symbol_c *)symbol->r_exp->accept(*this));

   451

    return compute_numeric_expression(left_type, right_type);

   452

  }

   453

   454

  void *visit(power_expression_c *symbol) {

   455

    symbol_c *left_type = base_type((symbol_c *)symbol->l_exp->accept(*this));

   456

    symbol_c *right_type = base_type((symbol_c *)symbol->r_exp->accept(*this));

   457

    if (typeid(*left_type) == typeid(real_type_name_c) and typeid(*right_type) == typeid(sint_type_name_c)) {return (void *)left_type;}

   458

    if (typeid(*left_type) == typeid(real_type_name_c) and typeid(*right_type) == typeid(int_type_name_c)) {return (void *)left_type;}

   459

    if (typeid(*left_type) == typeid(real_type_name_c) and typeid(*right_type) == typeid(dint_type_name_c)) {return (void *)left_type;}

   460

    if (typeid(*left_type) == typeid(real_type_name_c) and typeid(*right_type) == typeid(lint_type_name_c)) {return (void *)left_type;}

   461

    if (typeid(*left_type) == typeid(real_type_name_c) and typeid(*right_type) == typeid(usint_type_name_c)) {return (void *)left_type;}

   462

    if (typeid(*left_type) == typeid(real_type_name_c) and typeid(*right_type) == typeid(uint_type_name_c)) {return (void *)left_type;}

   463

    if (typeid(*left_type) == typeid(real_type_name_c) and typeid(*right_type) == typeid(udint_type_name_c)) {return (void *)left_type;}

   464

    if (typeid(*left_type) == typeid(real_type_name_c) and typeid(*right_type) == typeid(ulint_type_name_c)) {return (void *)left_type;}

   465

    if (typeid(*left_type) == typeid(lreal_type_name_c) and typeid(*right_type) == typeid(sint_type_name_c)) {return (void *)left_type;}

   466

    if (typeid(*left_type) == typeid(lreal_type_name_c) and typeid(*right_type) == typeid(int_type_name_c)) {return (void *)left_type;}

   467

    if (typeid(*left_type) == typeid(lreal_type_name_c) and typeid(*right_type) == typeid(dint_type_name_c)) {return (void *)left_type;}

   468

    if (typeid(*left_type) == typeid(lreal_type_name_c) and typeid(*right_type) == typeid(lint_type_name_c)) {return (void *)left_type;}

   469

    if (typeid(*left_type) == typeid(lreal_type_name_c) and typeid(*right_type) == typeid(usint_type_name_c)) {return (void *)left_type;}

   470

    if (typeid(*left_type) == typeid(lreal_type_name_c) and typeid(*right_type) == typeid(uint_type_name_c)) {return (void *)left_type;}

   471

    if (typeid(*left_type) == typeid(lreal_type_name_c) and typeid(*right_type) == typeid(udint_type_name_c)) {return (void *)left_type;}

   472

    if (typeid(*left_type) == typeid(lreal_type_name_c) and typeid(*right_type) == typeid(ulint_type_name_c)) {return (void *)left_type;}

   473

    ERROR;

   474

    return NULL;

   475

  }

   476

   477

  void *visit(neg_expression_c *symbol) {

   478

    symbol_c *exp_type = base_type((symbol_c *)symbol->exp->accept(*this));

   479

    if (typeid(*exp_type) == typeid(sint_type_name_c)) {return (void *)exp_type;}

   480

    if (typeid(*exp_type) == typeid(int_type_name_c)) {return (void *)exp_type;}

   481

    if (typeid(*exp_type) == typeid(dint_type_name_c)) {return (void *)exp_type;}

   482

    if (typeid(*exp_type) == typeid(lint_type_name_c)) {return (void *)exp_type;}

   483

    if (typeid(*exp_type) == typeid(usint_type_name_c)) {return (void *)exp_type;}

   484

    if (typeid(*exp_type) == typeid(uint_type_name_c)) {return (void *)exp_type;}

   485

    if (typeid(*exp_type) == typeid(udint_type_name_c)) {return (void *)exp_type;}

   486

    if (typeid(*exp_type) == typeid(ulint_type_name_c)) {return (void *)exp_type;}

   487

    if (typeid(*exp_type) == typeid(real_type_name_c)) {return (void *)exp_type;}

   488

    if (typeid(*exp_type) == typeid(lreal_type_name_c)) {return (void *)exp_type;}

   489

    if (typeid(*exp_type) == typeid(time_type_name_c)) {return (void *)exp_type;}

   490

    ERROR;

   491

    return NULL;

   492

  }

   493

   494

  void *visit(not_expression_c *symbol) {

   495

    symbol_c *exp_type = base_type((symbol_c *)symbol->exp->accept(*this));

   496

    if (typeid(*exp_type) == typeid(bool_type_name_c)) {return (void *)exp_type;}

   497

    ERROR;

   498

    return NULL;

   499

  }

   500

   501

  void *visit(function_invocation_c *symbol) {

   502

	  function_declaration_c *f_decl = function_symtable.find_value(symbol->function_name);

   503

   504

	  if (f_decl == function_symtable.end_value()) {

   505

      void *res = compute_standard_function_st(symbol);

   506

	    if (res == NULL)

   507

        ERROR;