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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

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 * License, or (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, but

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 * WITHOUT ANY WARRANTY; without even the implied warranty of

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

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 * Public License for more details.

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 *

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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.

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 *

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 * 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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 */

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    25

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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

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 * code.

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 */

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

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

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

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

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    40

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class generate_c_st_c: public generate_c_typedecl_c {

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  private:

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    /* 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

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     * in scope.

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     * This class does just that...

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

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

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     * 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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     *

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     * Note that functions cannot contain calls to function blocks,

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     * so we do not create an object instance when handling

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     * a function declaration.

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     */

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    search_fb_instance_decl_c *search_fb_instance_decl;

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

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

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

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     * or function currently being processed.

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     * The following object does just that...

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     * This object instance will then later be called while the

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     * remaining st code is being handled.

    66

     */

    67

    search_expression_type_c *search_expression_type;

    68

    69

    search_varfb_instance_type_c *search_varfb_instance_type;

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    71

    search_base_type_c search_base_type;

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    73

    symbol_c* current_array_type;

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    bool current_param_is_pointer;

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  public:

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

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    : generate_c_typedecl_c(s4o_ptr) {

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      search_fb_instance_decl = new search_fb_instance_decl_c(scope);

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      search_expression_type = new search_expression_type_c(scope);

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      search_varfb_instance_type = new search_varfb_instance_type_c(scope);

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      this->set_variable_prefix(variable_prefix);

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      current_array_type = NULL;

    85

      current_param_is_pointer = false;

    86

    }

    87

    88

    virtual ~generate_c_st_c(void) {

    89

      delete search_fb_instance_decl;

    90

      delete search_expression_type;

    91

      delete search_varfb_instance_type;

    92

    }

    93

    94

    95

  private:

    96

    /* Some function calls in the body of functions or function blocks

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     * may leave some parameters to their default values, and

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     * ignore some output parameters of the function being called.

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     * Our conversion of ST functions to C++ does not contemplate that,

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     * i.e. each called function must get all it's input and output

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     * parameters set correctly.

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     * For input parameters we merely need to call the function with

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     * the apropriate default value, but for output parameters

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     * we must create temporary variables to hold the output value.

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     *

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     * We declare all the temporary output variables at the begining of

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     * the body of each function or function block, and use them as

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     * in function calls later on as they become necessary...

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     * Note that we cannot create these variables just before a function

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     * call, as the function call itself may be integrated within an

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     * expression, or another function call!

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     *

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     * The variables are declared in the exact same order in which they

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     * will be used later on during the function calls, which allows us

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     * to simply re-create the name that was used for the temporary variable

   116

     * instead of keeping it in some list.

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     * The names are recreated by the temp_var_name_factory, after reset()

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     * has been called!

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     *

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     * This function will genertae code similar to...

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     *

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     *     INT __TMP_0 = 23;

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     *     REAL __TMP_1 = 45.5;

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     *     ...

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     */

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    temp_var_name_c temp_var_name_factory;

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   128

  public:

   129

    void generate(statement_list_c *stl) {

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      generate_c_tempvardecl_c generate_c_tempvardecl(&s4o);

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      generate_c_tempvardecl.generate(stl, &temp_var_name_factory);

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      stl->accept(*this);

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    }

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  private:

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   137

void *visit(eno_param_c *symbol) {

   138

  if (this->is_variable_prefix_null()) {

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    s4o.print("*");

   140

  }

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  else {

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    this->print_variable_prefix();

   143

  }

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  s4o.print("ENO");

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  return NULL;

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}

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

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/* B 1.4 - Variables */

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

   151

void *visit(symbolic_variable_c *symbol) {

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

   153

  if (!current_param_is_pointer && (vartype == search_var_instance_decl_c::external_vt || vartype == search_var_instance_decl_c::located_vt)) {

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    s4o.print("*(");

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    generate_c_base_c::visit(symbol);

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    s4o.print(")");

   157

  }

   158

  else if (current_param_is_pointer && vartype != search_var_instance_decl_c::external_vt && vartype != search_var_instance_decl_c::located_vt) {

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    s4o.print("&(");

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    generate_c_base_c::visit(symbol);

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    s4o.print(")");

   162

  }

   163

  else {

   164

    generate_c_base_c::visit(symbol);

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  }

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  return NULL;

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}

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

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/* B.1.4.1   Directly Represented Variables */

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

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

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void *visit(direct_variable_c *symbol) {

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  TRACE("direct_variable_c");

   175

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

   176

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

   177

  if (!current_param_is_pointer) {

   178

    s4o.print("*(");

   179

  }

   180

  this->print_variable_prefix();

   181

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

   182

  if (!current_param_is_pointer) {

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    s4o.print(")");

   184

  }

   185

  return NULL;

   186

}

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   188

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

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/* B.1.4.2   Multi-element Variables */

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

   191

   192

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

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//SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

   194

void *visit(array_variable_c *symbol) {

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  current_array_type = search_varfb_instance_type->get_type(symbol->subscripted_variable, false);

   196

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

   197

  if (current_array_type != NULL) {

   198

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

   199

    current_array_type = NULL;

   200

  }

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  return NULL;

   202

}

   203

   204

/* subscript_list ',' subscript */

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void *visit(subscript_list_c *symbol) {

   206

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

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    s4o.print("[__");

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    current_array_type->accept(*this);

   209

    s4o.print("_TRANSIDX");

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    print_integer(i);

   211

    s4o.print("(");

   212

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

   213

    s4o.print(")]");

   214

  }

   215

  return NULL;

   216

}

   217

   218

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

   220

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

   221

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

   222

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

   223

/* B 3.1 - Expressions */

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

   225

void *visit(or_expression_c *symbol) {

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

   227

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

   228

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

   229

      ERROR;

   230

  if (search_expression_type->is_bool_type(left_type))

   231

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

   232

  if (search_expression_type->is_binary_type(left_type))

   233

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

   234

  ERROR;

   235

  return NULL;

   236

}

   237

   238

void *visit(xor_expression_c *symbol) {

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

   240

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

   241

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

   242

      ERROR;

   243

  if (search_expression_type->is_bool_type(left_type)) {

   244

    s4o.print("(");

   245

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

   246

    s4o.print(" && !");

   247

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

   248

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

   249

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

   250

    s4o.print(" && ");

   251

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

   252

    s4o.print(")");

   253

    return NULL;

   254

  }

   255

  if (search_expression_type->is_binary_type(left_type))

   256

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

   257

  ERROR;

   258

  return NULL;

   259

}

   260

   261

void *visit(and_expression_c *symbol) {

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

   263

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

   264

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

   265

      ERROR;

   266

  if (search_expression_type->is_bool_type(left_type))

   267

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

   268

  if (search_expression_type->is_binary_type(left_type))

   269

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

   270

  ERROR;

   271

  return NULL;

   272

}

   273

   274

void *visit(equ_expression_c *symbol) {

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

   276

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

   277

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

   278

      ERROR;

   279

  if (search_expression_type->is_time_type(left_type) ||

   280

      search_expression_type->is_string_type(left_type))

   281

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

   282

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

   283

}

   284

   285

void *visit(notequ_expression_c *symbol) {

   286

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

   287

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

   288

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

   289

      ERROR;

   290

  if (search_expression_type->is_time_type(left_type) ||

   291

      search_expression_type->is_string_type(left_type))

   292

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

   293

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

   294

}

   295

   296

void *visit(lt_expression_c *symbol) {

   297

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

   298

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

   299

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

   300

      ERROR;

   301

  if (search_expression_type->is_time_type(left_type) ||

   302

      search_expression_type->is_string_type(left_type))

   303

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

   304

  if (!search_base_type.type_is_enumerated(left_type))

   305

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

   306

  ERROR;

   307

  return NULL;

   308

}

   309

   310

void *visit(gt_expression_c *symbol) {

   311

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

   312

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

   313

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

   314

      ERROR;

   315

  if (search_expression_type->is_time_type(left_type) ||

   316

      search_expression_type->is_string_type(left_type))

   317

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

   318

  if (!search_base_type.type_is_enumerated(left_type))

   319

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

   320

  ERROR;

   321

  return NULL;

   322

}

   323

   324

void *visit(le_expression_c *symbol) {

   325

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

   326

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

   327

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

   328

      ERROR;

   329

  if (search_expression_type->is_time_type(left_type) ||

   330

      search_expression_type->is_string_type(left_type))

   331

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

   332

  if (!search_base_type.type_is_enumerated(left_type))

   333

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

   334

  ERROR;

   335

  return NULL;

   336

}

   337

   338

void *visit(ge_expression_c *symbol) {

   339

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

   340

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

   341

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

   342

      ERROR;

   343

  if (search_expression_type->is_time_type(left_type) ||

   344

      search_expression_type->is_string_type(left_type))

   345

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

   346

  if (!search_base_type.type_is_enumerated(left_type))

   347

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

   348

  ERROR;

   349

  return NULL;

   350

}

   351

   352

void *visit(add_expression_c *symbol) {

   353

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

   354

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

   355

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

   356

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

   357

      (typeid(*left_type) == typeid(dt_type_name_c) && typeid(*right_type) == typeid(time_type_name_c)))

   358

    return print_binary_function("__TIME_ADD", symbol->l_exp, symbol->r_exp);

   359

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

   360

      ERROR;

   361

  if (search_expression_type->is_integer_type(left_type) || search_expression_type->is_real_type(left_type))

   362

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

   363

  ERROR;

   364

  return NULL;

   365

}

   366

   367

void *visit(sub_expression_c *symbol) {

   368

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

   369

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

   370

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

   371

      (typeid(*left_type) == typeid(date_type_name_c) && typeid(*right_type) == typeid(date_type_name_c)) ||

   372

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

   373

      (typeid(*left_type) == typeid(tod_type_name_c) && typeid(*right_type) == typeid(tod_type_name_c)) ||

   374

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

   375

      (typeid(*left_type) == typeid(dt_type_name_c) && typeid(*right_type) == typeid(dt_type_name_c)))

   376

    return print_binary_function("__TIME_SUB", symbol->l_exp, symbol->r_exp);

   377

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

   378

      ERROR;

   379

  if (search_expression_type->is_integer_type(left_type) || search_expression_type->is_real_type(left_type))

   380

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

   381

  ERROR;

   382

  return NULL;

   383

}

   384

   385

void *visit(mul_expression_c *symbol) {

   386

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

   387

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

   388

  if ((typeid(*left_type) == typeid(time_type_name_c) && search_expression_type->is_integer_type(right_type)) ||

   389

      (typeid(*left_type) == typeid(time_type_name_c) && search_expression_type->is_real_type(right_type)))

   390

    return print_binary_function("__TIME_MUL", symbol->l_exp, symbol->r_exp);

   391

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

   392

      ERROR;

   393

  if (search_expression_type->is_integer_type(left_type) || search_expression_type->is_real_type(left_type))

   394

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

   395

  ERROR;

   396

  return NULL;

   397

}

   398

   399

void *visit(div_expression_c *symbol) {

   400

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

   401

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

   402

  if ((typeid(*left_type) == typeid(time_type_name_c) && search_expression_type->is_integer_type(right_type)) ||

   403

      (typeid(*left_type) == typeid(time_type_name_c) && search_expression_type->is_real_type(right_type)))

   404

    return print_binary_function("__TIME_DIV", symbol->l_exp, symbol->r_exp);

   405

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

   406

      ERROR;

   407

  if (search_expression_type->is_integer_type(left_type) || search_expression_type->is_real_type(left_type))

   408

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

   409

  ERROR;

   410

  return NULL;

   411

}

   412

   413

void *visit(mod_expression_c *symbol) {

   414

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

   415

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

   416

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

   417

      ERROR;

   418

  if (search_expression_type->is_integer_type(left_type) || search_expression_type->is_real_type(left_type)) {

   419

    s4o.print("((");

   420

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

   421

    s4o.print(" == 0)?0:");

   422

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

   423

    s4o.print(")");

   424

    return NULL;

   425

  }

   426

  ERROR;

   427

  return NULL;

   428

}

   429

   430

/* TODO: power expression... */

   431

void *visit(power_expression_c *symbol) {ERROR; return print_binary_expression(symbol->l_exp, symbol->r_exp, " ** ");}

   432

void *visit(neg_expression_c *symbol) {

   433

  symbol_c *exp_type = search_expression_type->get_type(symbol->exp);

   434

  if (search_expression_type->is_integer_type(exp_type) || search_expression_type->is_real_type(exp_type))

   435

    return print_unary_expression(symbol->exp, " -");

   436

  ERROR;

   437

  return NULL;

   438

}

   439

   440

void *visit(not_expression_c *symbol) {

   441

  symbol_c *exp_type = search_expression_type->get_type(symbol->exp);

   442

  if (search_expression_type->is_binary_type(exp_type))

   443

    return print_unary_expression(symbol->exp, search_expression_type->is_bool_type(exp_type)?"!":"~");

   444

  ERROR;

   445

  return NULL;

   446

}

   447

   448

void *visit(function_invocation_c *symbol) {

   449

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

   450

   451

  symbol_c* function_type_prefix = NULL;

   452

  symbol_c* function_name = NULL;

   453

  symbol_c* function_type_suffix = NULL;

   454

  std::list<FUNCTION_PARAM> param_list;

   455

  FUNCTION_PARAM *param;

   456

   457

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

   458

    /* The function called is not in the symtable, so we test if it is a

   459

     * standard function defined in standard */

   460

   461

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

   462

    if (current_function_type == function_none) ERROR;

   463

   464

    symbol_c *function_return_type = search_expression_type->get_type(symbol);

   465

   466

    function_call_param_iterator_c function_call_param_iterator(symbol);

   467

   468

    identifier_c en_param_name("EN");

   469

    /* Get the value from EN param */

   470

    symbol_c *EN_param_value = function_call_param_iterator.search(&en_param_name);

   471

    if (EN_param_value == NULL)

   472

      EN_param_value = (symbol_c*)(new boolean_literal_c((symbol_c*)(new bool_type_name_c()), new boolean_true_c()));

   473

    ADD_PARAM_LIST(EN_param_value, (symbol_c*)(new bool_type_name_c()), function_param_iterator_c::direction_in)

   474

   476

    /* Get the value from ENO param */

   477

    symbol_c *ENO_param_value = function_call_param_iterator.search(&eno_param_name);

   478

    ADD_PARAM_LIST(ENO_param_value, (symbol_c*)(new bool_type_name_c()), function_param_iterator_c::direction_out)

   479

   480

    int nb_param = ((list_c *)symbol->parameter_assignment_list)->n;

   481

   482

    #include "st_code_gen.c"

   483

   484

  }

   485

  else {

   486

    /* loop through each function parameter, find the value we should pass

   487

     * to it, and then output the c equivalent...

   488

     */

   489

    function_param_iterator_c fp_iterator(f_decl);

   490

   491

    function_name = symbol->function_name;

   492

   493

    identifier_c *param_name;

   494

    function_call_param_iterator_c function_call_param_iterator(symbol);

   495

    for(int i = 1; (param_name = fp_iterator.next()) != NULL; i++) {

   496

   497

      function_param_iterator_c::param_direction_t param_direction = fp_iterator.param_direction();

   498

   499

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

   500

      symbol_c *param_value = function_call_param_iterator.search(param_name);

   501

   502

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

   503

      if (param_value == NULL)

   504

        param_value = function_call_param_iterator.next();

   505

   506

      if (param_value == NULL && param_direction == function_param_iterator_c::direction_in) {

   507

        /* No value given for parameter, so we must use the default... */

   508

        /* First check whether default value specified in function declaration...*/

   509

        param_value = fp_iterator.default_value();

   510

      }

   511

   512

      symbol_c *param_type = fp_iterator.param_type();

   513

      if (param_type == NULL) ERROR;

   514

   515

      ADD_PARAM_LIST(param_value, param_type, param_direction)

   516