1

/*

     2

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

     3

 *

     4

 *  Copyright (C) 2009-2011  Mario de Sousa (msousa@fe.up.pt)

     5

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

     6

 *

     7

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

     8

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

     9

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

    10

 *  (at your option) any later version.

    11

 *

    12

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

    13

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

    14

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    15

 *  GNU General Public License for more details.

    16

 *

    17

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

    18

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

    19

 *

    20

 *

    21

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

    22

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

    23

 */

    24

    25

/*

    26

 * An IEC 61131-3 compiler.

    27

 *

    28

 * Based on the

    29

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

    30

 *

    31

 */

    32

    33

    34

/*

    35

 * This is the main stage 3a file.

    36

 *

    37

 * In stage 3a some helpful symbol tables are instanciated and populated.

    38

 * These symbol tables wll then be used by stage3b and atage4 code generators.

    39

 */

    40

    41

    42

    43

    44

    45

    46

// #include <stdio.h>  /* required for NULL */

    47

#include <string>

    48

#include <iostream>

    49

#include <sstream>

    50

#include <typeinfo>

    51

#include <list>

    52

#include <strings.h>

    53

// #include <string.h>  /* required for strlen() */

    54

// #include <stdlib.h>  /* required for atoi() */

    55

// #include <errno.h>   /* required for errno */

    56

    57

#include "../util/symtable.hh"

    58

#include "../util/dsymtable.hh"

    59

#include "../absyntax/visitor.hh"

    60

#include "../main.hh" // required for ERROR() and ERROR_MSG() macros.

    61

    62

    63

    64

//#define DEBUG

    65

#ifdef DEBUG

    66

#define TRACE(classname) printf("\n____%s____\n",classname);

    67

#else

    68

#define TRACE(classname)

    69

#endif

    70

    71

    72

    73

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

    74

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

    75

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

    76

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

    77

    78

    79

/* returns 0 if the names are equal!! */

    80

/* NOTE: it must ignore case!! */

    81

int compare_identifiers(symbol_c *ident1, symbol_c *ident2) {

    82

    83

  token_c *name1 = dynamic_cast<token_c *>(ident1);

    84

  token_c *name2 = dynamic_cast<token_c *>(ident2);

    85

    86

  if ((name1 == NULL) || (name2 == NULL))

    87

    /* invalid identifiers... */

    88

    return -1;

    89

    90

  if (strcasecmp(name1->value, name2->value) == 0)

    91

    return 0;

    92

    93

  /* identifiers do not match! */

    94

  return 1;

    95

}

    96

    97

    98

    99

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

   100

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

   101

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

   102

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

   103

   104

   105

   106

/* A symbol table with all globally declared functions... */

   107

function_declaration_c null_symbol1(NULL,NULL,NULL,NULL);

   108

dsymtable_c<function_declaration_c *, &null_symbol1> function_symtable;

   109

   110

/* A symbol table with all globally declared functions block types... */

   111

function_block_declaration_c null_symbol2(NULL,NULL,NULL);

   112

symtable_c<function_block_declaration_c *, &null_symbol2> function_block_type_symtable;

   113

   114

/* A symbol table with all globally declared program types... */

   115

program_declaration_c null_symbol3(NULL,NULL,NULL);

   116

symtable_c<program_declaration_c *, &null_symbol3> program_type_symtable;

   117

   118

/* A symbol table with all user declared type definitions... */

   119

/* Note that function block types and program types have their

   120

 * own symbol tables, so do not get placed in this symbol table!

   121

 *

   122

 * The symbol_c * associated to the value will point to the data type declaration.

   123

 */

   124

symbol_c null_symbol4;

   125

symtable_c<symbol_c *, &null_symbol4> type_symtable;

   126

   127

/* A symbol table with all values declared for enumerated type... */

   128

/* Notes:

   129

 * - if the value is defined multiple times the value

   130

 * is the null pointer.

   131

 *

   132

 * - The stored symbol_c * associated to the value points to the enumerated_type_name

   133

 * (i.e. the name of the enumerated data type) in which the the value/identifier

   134

 * is used/declared.

   135

 *

   136

 * - We could re-use the null_symbol4 object, but it is safer to use a distinct object

   137

 *   (i.e. it might make it easier to find strange bugs).

   138

 */

   139

symbol_c null_symbol5;

   140

symtable_c<symbol_c *, &null_symbol5> enumerated_value_symtable;

   141

   142

   143

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

   144

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

   145

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

   146

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

   147

   148

   149

class populate_symtables_c: public iterator_visitor_c {

   150

   151

  private:

   152

	symbol_c *current_enumerated_type;

   153

   154

  public:

   155

    populate_symtables_c(void) {

   156

    	current_enumerated_type = NULL;

   157

    };

   158

    virtual ~populate_symtables_c(void) {}

   159

   160

   161

  public:

   162

   163

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

   164

  /* B.1 - Common elements */

   165

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

   166

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

   167

  /* B 1.1 - Letters, digits and identifiers */

   168

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

   169

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

   170

  /* B 1.2 - Constants */

   171

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

   172

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

   173

  /* B 1.2.1 - Numeric Literals */

   174

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

   175

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

   176

  /* B.1.2.2   Character Strings */

   177

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

   178

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

   179

  /* B 1.2.3 - Time Literals */

   180

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

   181

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

   182

  /* B 1.2.3.1 - Duration */

   183

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

   184

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

   185

  /* B 1.2.3.2 - Time of day and Date */

   186

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

   187

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

   188

  /* B.1.3 - Data types */

   189

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

   190

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

   191

  /* B 1.3.1 - Elementary Data Types */

   192

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

   193

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

   194

  /* B.1.3.2 - Generic data types */

   195

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

   196

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

   197

  /* B 1.3.3 - Derived data types */

   198

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

   199

   200

  /*  subrange_type_name ':' subrange_spec_init */

   201

  void *visit(subrange_type_declaration_c *symbol) {

   202

    TRACE("subrange_type_declaration_c");  

   203

    type_symtable.insert(symbol->subrange_type_name, symbol->subrange_spec_init);

   204

    return NULL;

   205

  }

   206

   207

   208

  /*  enumerated_type_name ':' enumerated_spec_init */

   209

  void *visit(enumerated_type_declaration_c *symbol) {

   210

    TRACE("enumerated_type_declaration_c");

   211

    type_symtable.insert(symbol->enumerated_type_name, symbol->enumerated_spec_init);

   212

    current_enumerated_type = symbol->enumerated_type_name;

   213

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

   214

    current_enumerated_type = NULL;

   215

    return NULL;

   216

  }

   217

   218

  /* enumerated_specification ASSIGN enumerated_value */

   219

  void *visit(enumerated_spec_init_c *symbol) {

   220

    return symbol->enumerated_specification->accept(*this);

   221

  }

   222

   223

  /* [enumerated_type_name '#'] identifier */

   224

  void *visit(enumerated_value_c *symbol) {

   225

    if (current_enumerated_type != NULL) {

   226

      if (symbol->type != NULL) ERROR;

   227

   228

      symbol_c *value_type = enumerated_value_symtable.find_value(symbol->value);

   229

      /* NOTE: The following condition checks whether the same identifier is used more than once

   230

       *       when defining the enumerated values of the type declaration of the new enumerated type.

   231

       *       If this occurs, then the program beeing compiled contains a semantic error, which

   232

       *       must be caught and reported by the semantic analyser. However, since

   233

       *       this code is run before the semantic analyser, we must not yet raise the ERROR (internal

   234

       *       compiler error message).

   235

       *       For this reason, the follosing check is commented out.

   236

       */

   237

      /* if (value_type == current_enumerated_type) ERROR; */

   238

   239

      if (value_type == enumerated_value_symtable.end_value())

   240

	/* This identifier has not yet been used in any previous declaration of an enumeration data type.

   241

	 * so we add it to the symbol table.

   242

	 */

   243

        enumerated_value_symtable.insert(symbol->value, current_enumerated_type);

   244

      else if (value_type != NULL)

   245

	/* This identifier has already been used in a previous declaration of an enumeration data type.

   246

	 * so we set the symbol in symbol table pointing to NULL.

   247

	 */

   248

        enumerated_value_symtable.set(symbol->value, NULL);

   249

    }

   250

    return NULL;

   251

  }

   252

   253

  /*  identifier ':' array_spec_init */

   254

  void *visit(array_type_declaration_c *symbol) {

   255

    TRACE("array_type_declaration_c");

   256

    type_symtable.insert(symbol->identifier, symbol->array_spec_init);

   257

    return NULL;

   258

  }

   259

   260

   261

  /*  simple_type_name ':' simple_spec_init */

   262

  void *visit(simple_type_declaration_c *symbol) {

   263

    TRACE("simple_type_declaration_c");

   264

    type_symtable.insert(symbol->simple_type_name, symbol->simple_spec_init);

   265

    return NULL;

   266

  }

   267

   268

   269

  /*  structure_type_name ':' structure_specification */

   270

  void *visit(structure_type_declaration_c *symbol) {

   271

    TRACE("structure_type_declaration_c");

   272

    type_symtable.insert(symbol->structure_type_name, symbol->structure_specification);

   273

    return NULL;

   274

  }

   275

   276

   277

  /*  string_type_name ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init */

   278

  // SYM_REF4(string_type_declaration_c,	string_type_name,

   279

  //    					elementary_string_type_name,

   280

  //    					string_type_declaration_size,

   281

  //    					string_type_declaration_init) /* may be == NULL! */

   282

  void *visit(string_type_declaration_c *symbol)	{

   283

    TRACE("string_type_declaration_c");

   284

    type_symtable.insert(symbol->string_type_name, symbol);

   285

    return NULL;

   286

}

   287

   288

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

   289

  /* B 1.4 - Variables */

   290

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

   291

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

   292

  /* B.1.4.1   Directly Represented Variables */

   293

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

   294

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

   295

  /* B.1.4.2   Multi-element Variables */

   296

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

   297

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

   298

  /* B 1.4.3 - Declaration & Initialisation */

   299

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

   300

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

   301

  /* B.1.5 - Program organization units */

   302

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

   303

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

   304

  /* B 1.5.1 - Functions */

   305

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

   306

  public:

   307

  /*   FUNCTION derived_function_name ':' elementary_type_name io_OR_function_var_declarations_list function_body END_FUNCTION */

   308

  /* | FUNCTION derived_function_name ':' derived_type_name io_OR_function_var_declarations_list function_body END_FUNCTION */

   309

  void *visit(function_declaration_c *symbol) {

   310

    TRACE("function_declaration_c");

   311

    function_symtable.insert(symbol->derived_function_name, symbol);

   312

   313

    /* symbol->derived_function_name->accept(*this);  */ /* Function name */

   314

    /* symbol->type_name->accept(*this);              */ /* return data type */

   315

    /* symbol->var_declarations_list->accept(*this);  */ /* Function parameters and variables */

   316

    /* symbol->function_body->accept(*this);          */ /* Function body */

   317

    return NULL;

   318

  }

   319

   320

   321

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

   322

  /* B 1.5.2 - Function Blocks */

   323

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

   324

  public:

   325

  /*  FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */

   326

  //SYM_REF4(function_block_declaration_c, fblock_name, var_declarations, fblock_body, unused)

   327

  void *visit(function_block_declaration_c *symbol) {

   328

    TRACE("function_block_declaration_c");

   329

    function_block_type_symtable.insert(symbol->fblock_name, symbol);

   330

  /*

   331

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

   332

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

   333

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

   334

  */

   335

    return NULL;

   336

  }

   337

   338

   339

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

   340

  /* B 1.5.3 - Programs */

   341

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

   342

  public:

   343

  /*  PROGRAM program_type_name program_var_declarations_list function_block_body END_PROGRAM */

   344

  //SYM_REF4(program_declaration_c, program_type_name, var_declarations, function_block_body, unused)

   345

  void *visit(program_declaration_c *symbol) {

   346

    TRACE("program_declaration_c");

   347

    program_type_symtable.insert(symbol->program_type_name, symbol);

   348

  /*

   349

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

   350

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

   351

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

   352

  */

   353

    return NULL;

   354

  }

   355

   356

}; /* populate_symtables_c */

   357

   358

   359

   360

   361

   362

void absyntax_utils_init(symbol_c *tree_root) {

   363

  populate_symtables_c populate_symbols;

   364

   365

  tree_root->accept(populate_symbols);

   366

}

   367