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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

 *

     8

 * 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.

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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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 */

    24

    25

    26

/*

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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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 */

    33

    34

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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_cc_st_c: public generate_cc_typedecl_c {

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    43

  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...

    64

     * This object instance will then later be called while the

    65

     * 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

  public:

    72

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

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    : generate_cc_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);

    78

    }

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    80

    virtual ~generate_cc_st_c(void) {

    81

      delete search_fb_instance_decl;

    82

      delete search_expression_type;

    83

      delete search_varfb_instance_type;

    84

    }

    85

    86

    87

  private:

    88

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

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     * may leave some parameters to their default values, and

    90

     * ignore some output parameters of the function being called.

    91

     * 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...

   101

     * 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

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     * 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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     *

   112

     * 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;

   116

     *     ...

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     */

   118

    temp_var_name_c temp_var_name_factory;

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   120

  public:

   121

    void generate(statement_list_c *stl) {

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      generate_cc_tempvardecl_c generate_cc_tempvardecl(&s4o);

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      generate_cc_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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/*********************/

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/* B 1.4 - Variables */

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

   132

void *visit(symbolic_variable_c *symbol) {

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

   134

  if (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_cc_base_c::visit(symbol);

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    s4o.print(")");

   138

  }

   139

  else {

   140

    generate_cc_base_c::visit(symbol);

   141

  }

   142

  return NULL;

   143

}

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

   146

/* B.1.4.1   Directly Represented Variables */

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

   148

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

   149

void *visit(direct_variable_c *symbol) {

   150

  TRACE("direct_variable_c");

   151

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

   152

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

   153

  s4o.print("*(");

   154

  this->print_variable_prefix();

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

   156

  s4o.print(")");

   157

  return NULL;

   158

}

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   160

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

   161

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

   162

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

   163

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

   164

/* B 3.1 - Expressions */

   165

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

   166

void *visit(or_expression_c *symbol) {

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

   168

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

   169

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

   170

      ERROR;

   171

  if (search_expression_type->is_bool_type(left_type))

   172

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

   173

  if (search_expression_type->is_binary_type(left_type))

   174

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

   175

  ERROR;

   176

  return NULL;

   177

}

   178

   179

void *visit(xor_expression_c *symbol) {

   180

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

   181

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

   182

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

   183

      ERROR;

   184

  if (search_expression_type->is_bool_type(left_type)) {

   185

    s4o.print("(");

   186

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

   187

    s4o.print(" && !");

   188

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

   189

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

   190

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

   191

    s4o.print(" && ");

   192

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

   193

    s4o.print(")");

   194

  }

   195

  if (search_expression_type->is_binary_type(left_type))

   196

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

   197

  ERROR;

   198

  return NULL;

   199

}

   200

   201

void *visit(and_expression_c *symbol) {

   202

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

   203

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

   204

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

   205

      ERROR;

   206

  if (search_expression_type->is_bool_type(left_type))

   207

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

   208

  if (search_expression_type->is_binary_type(left_type))

   209

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

   210

  ERROR;

   211

  return NULL;

   212

}

   213

   214

void *visit(equ_expression_c *symbol) {

   215

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

   216

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

   217

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

   218

      ERROR;

   219

  if (search_expression_type->is_time_type(left_type))

   220

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

   221

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

   222

}

   223

   224

void *visit(notequ_expression_c *symbol) {

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

   226

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

   227

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

   228

      ERROR;

   229

  if (search_expression_type->is_time_type(left_type))

   230

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

   231

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

   232

}

   233

   234

void *visit(lt_expression_c *symbol) {

   235

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

   236

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

   237

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

   238

      ERROR;

   239

  if (search_expression_type->is_time_type(left_type))

   240

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

   241

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

   242

}

   243

   244

void *visit(gt_expression_c *symbol) {

   245

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

   246

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

   247

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

   248

      ERROR;

   249

  if (search_expression_type->is_time_type(left_type))

   250

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

   251

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

   252

}

   253

   254

void *visit(le_expression_c *symbol) {

   255

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

   256

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

   257

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

   258

      ERROR;

   259

  if (search_expression_type->is_time_type(left_type))

   260

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

   261

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

   262

}

   263

   264

void *visit(ge_expression_c *symbol) {

   265

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

   266

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

   267

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

   268

      ERROR;

   269

  if (search_expression_type->is_time_type(left_type))

   270

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

   271

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

   272

}

   273

   274

void *visit(add_expression_c *symbol) {

   275

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

   278

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

   279

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

   280

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

   281

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

   282

      ERROR;

   283

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

   284

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

   285

  ERROR;

   286

  return NULL;

   287

}

   288

   289

void *visit(sub_expression_c *symbol) {

   290

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

   291

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

   292

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

   293

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

   294

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

   295

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

   296

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

   297

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

   298

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

   299

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

   300

      ERROR;

   301

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

   302

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

   303

  ERROR;

   304

  return NULL;

   305

}

   306

   307

void *visit(mul_expression_c *symbol) {

   308

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

   309

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

   310

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

   311

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

   312

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

   313

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

   314

      ERROR;

   315

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

   316

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

   317

  ERROR;

   318

  return NULL;

   319

}

   320

   321

void *visit(div_expression_c *symbol) {

   322

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

   323

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

   324

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

   325

      ERROR;

   326

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

   327

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

   328

  ERROR;

   329

  return NULL;

   330

}

   331

   332

void *visit(mod_expression_c *symbol) {

   333

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

   334

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

   335

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

   336

      ERROR;

   337

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

   338

    s4o.print("((");

   339

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

   340

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

   341

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

   342

    s4o.print(")");

   343

    return NULL;

   344

  }

   345

  ERROR;

   346

  return NULL;

   347

}

   348

   349

/* TODO: power expression... */

   350

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

   351

void *visit(neg_expression_c *symbol) {return print_unary_expression(symbol->exp, " -");}

   353

   354

void *visit(function_invocation_c *symbol) {

   355

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

   356

   357

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

   358

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

   359

     * standard function defined in standard */

   360

   361

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

   362

    if (current_function_type == function_none) ERROR;

   363

   364

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

   365

   366

    function_call_param_iterator_c function_call_param_iterator(symbol);

   367

   368

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

   369

   370

#include "st_code_gen.c"

   371

   372

#if 0

   373

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

   374

      symbol_c *param_name = NULL;

   375

      switch (current_function_type) {

   376

        case function_add:

   377

        case function_and:

   378

        case function_or:

   379

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

   380

          break;

   381

        case function_sub:

   382

          if (current_param < 2)

   383

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

   384

          else

   385

            ERROR;

   386

          break;

   387

        default: ERROR;

   388

      }

   389

   390

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

   391

      symbol_c *param_value = function_call_param_iterator.search(param_name);

   392

      delete param_name;

   393

   394

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

   395

      if (param_value == NULL)

   396

        param_value = function_call_param_iterator.next();

   397

   398

      if (param_value == NULL) ERROR;

   399

   400

      switch (current_function_type) {

   401

        case function_add:

   402

          if (search_expression_type->is_time_type(function_return_type)) {

   403

            if (current_param == 0) {

   404

              s4o.print("__time_add(");

   405

              param_value->accept(*this);

   406

            }

   407

            else if (current_param == 1) {

   408

              s4o.print(", ");

   409

              param_value->accept(*this);

   410

              s4o.print(")");

   411

            }

   412

            else ERROR;

   413

          }

   414

          else {

   415

            if (current_param == 0)

   416

              s4o.print("(");

   417

            else

   418

              s4o.print(" + ");

   419

            param_value->accept(*this);

   420

            if (current_param == nb_param - 1)

   421

              s4o.print(")");

   422

          }

   423

          break;

   424

        case function_sub:

   425

          if (search_expression_type->is_time_type(function_return_type)) {

   426

            if (current_param == 0) {

   427

              s4o.print("__time_sub(");

   428

              param_value->accept(*this);

   429

            }

   430

            else if (current_param == 1) {

   431

              s4o.print(", ");

   432

              param_value->accept(*this);

   433

              s4o.print(")");

   434

            }

   435

            else ERROR;

   436

          }

   437

          else {

   438

            if (current_param == 0) {

   439

              s4o.print("(");

   440

              param_value->accept(*this);

   441

            }

   442

            else if (current_param == 1) {

   443

              s4o.print(" - ");

   444

              param_value->accept(*this);

   445

              s4o.print(")");

   446

            }

   447

            else ERROR;

   448

          }

   449

          break;

   450

        case function_and:

   451

          if (current_param == 0)

   452

            s4o.print("(");

   453

          else

   454

            if (search_expression_type->is_bool_type(function_return_type))

   455

              s4o.print(" && ");

   456

            else

   457

              s4o.print(" & ");

   458

          param_value->accept(*this);

   459

          if (current_param == nb_param - 1)

   460

            s4o.print(")");

   461

          break;

   462

        case function_or:

   463

          if (current_param == 0)

   464

            s4o.print("(");

   465

          else

   466

            if (search_expression_type->is_bool_type(function_return_type))

   467

              s4o.print(" || ");

   468

            else

   469

              s4o.print(" | ");

   470

          param_value->accept(*this);

   471

          if (current_param == nb_param - 1)

   472

            s4o.print(")");

   473

          break;

   474

        default: ERROR;

   475

      }

   476

    } /* for(...) */

   477

#endif

   478

  }

   479

  else {

   480

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

   481

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

   482

     */

   483

    function_param_iterator_c fp_iterator(f_decl);

   484

   485

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

   486

    s4o.print("(");

   487

    s4o.indent_right();

   488

   489

    identifier_c *param_name;

   490

    function_call_param_iterator_c function_call_param_iterator(symbol);

   491

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

   492

      if (i != 1)

   493

        s4o.print(",\n"+s4o.indent_spaces);

   494

   495

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

   496

   497

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

   498

      symbol_c *param_value = function_call_param_iterator.search(param_name);

   499

   500

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