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/*

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

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 *

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 *  Copyright (C) 2003-2011  Mario de Sousa (msousa@fe.up.pt)

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

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 *

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

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

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

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 *  (at your option) any later version.

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 *

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

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

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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

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 *  GNU General Public License for more details.

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 *

    17

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

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

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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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 *

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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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 */

    27

    28

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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, or SFC

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 * code.

    35

 */

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    37

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    39

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

    40

    41

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

    42

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

    43

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

    44

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

    45

    46

    47

class generate_c_st_c: public generate_c_typedecl_c {

    48

    49

  public:

    50

    typedef enum {

    51

      expression_vg,

    52

      assignment_vg,

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      complextype_base_vg,

    54

      complextype_base_assignment_vg,

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      complextype_suffix_vg,

    56

      fparam_output_vg

    57

    } variablegeneration_t;

    58

    59

    typedef enum {

    60

      single_cg,

    61

      subrange_cg,

    62

      none_cg

    63

    } casegeneration_t;

    64

    65

  private:

    66

    /* 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...

    70

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

    71

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

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     * This object instance will then later be called while the

    73

     * 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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     */

    79

    search_fb_instance_decl_c *search_fb_instance_decl;

    80

    81

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

    82

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

    83

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

    84

     * or function currently being processed.

    85

     * The following object does just that...

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     * This object instance will then later be called while the

    87

     * remaining st code is being handled.

    88

     */

    89

    search_expression_type_c *search_expression_type;

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    91

    search_varfb_instance_type_c *search_varfb_instance_type;

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    93

    search_base_type_c search_base_type;

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    95

    symbol_c* current_array_type;

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    symbol_c* current_param_type;

    97

    98

    int fcall_number;

    99

    symbol_c *fbname;

   100

   101

    bool first_subrange_case_list;

   102

   103

    variablegeneration_t wanted_variablegeneration;

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    casegeneration_t wanted_casegeneration;

   105

   106

  public:

   107

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

   108

    : generate_c_typedecl_c(s4o_ptr) {

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      search_fb_instance_decl = new search_fb_instance_decl_c(scope);

   110

      search_expression_type = new search_expression_type_c(scope);

   111

      search_varfb_instance_type = new search_varfb_instance_type_c(scope);

   112

      this->set_variable_prefix(variable_prefix);

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      current_array_type = NULL;

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      current_param_type = NULL;

   115

      fcall_number = 0;

   116

      fbname = name;

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      wanted_variablegeneration = expression_vg;

   118

      wanted_casegeneration = none_cg;

   119

    }

   120

   121

    virtual ~generate_c_st_c(void) {

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      delete search_fb_instance_decl;

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      delete search_expression_type;

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      delete search_varfb_instance_type;

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    }

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   127

   128

  public:

   129

    void generate(statement_list_c *stl) {

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      stl->accept(*this);

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    }

   132

   133

  private:

   134

   135

void *print_getter(symbol_c *symbol) {

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

   137

  if (wanted_variablegeneration == fparam_output_vg) {

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  	if (vartype == search_var_instance_decl_c::external_vt)

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      s4o.print(GET_EXTERNAL_BY_REF);

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    else if (vartype == search_var_instance_decl_c::located_vt)

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      s4o.print(GET_LOCATED_BY_REF);

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    else

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      s4o.print(GET_VAR_BY_REF);

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  }

   145

  else {

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	if (vartype == search_var_instance_decl_c::external_vt)

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	  s4o.print(GET_EXTERNAL);

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	else if (vartype == search_var_instance_decl_c::located_vt)

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	  s4o.print(GET_LOCATED);

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	else

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	  s4o.print(GET_VAR);

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  }

   153

  s4o.print("(");

   154

   155

  variablegeneration_t old_wanted_variablegeneration = wanted_variablegeneration;

   156

  wanted_variablegeneration = complextype_base_vg;

   157

  symbol->accept(*this);

   158

  if (search_varfb_instance_type->type_is_complex())

   159

    s4o.print(",");

   160

  wanted_variablegeneration = complextype_suffix_vg;

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  symbol->accept(*this);

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  s4o.print(")");

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  wanted_variablegeneration = old_wanted_variablegeneration;

   164

  return NULL;

   165

}

   166

   167

void *print_setter(symbol_c* symbol,

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		symbol_c* type,

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		symbol_c* value,

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		symbol_c* fb_symbol = NULL,

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		symbol_c* fb_value = NULL) {

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  bool type_is_complex = false;

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  if (fb_symbol == NULL) {

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

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    type_is_complex = search_varfb_instance_type->type_is_complex();

   177

    if (vartype == search_var_instance_decl_c::external_vt)

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      s4o.print(SET_EXTERNAL);

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    else if (vartype == search_var_instance_decl_c::located_vt)

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      s4o.print(SET_LOCATED);

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    else

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      s4o.print(SET_VAR);

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  }

   184

  else

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	s4o.print(SET_VAR);

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  s4o.print("(");

   187

   188

  if (fb_symbol != NULL) {

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    print_variable_prefix();

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    fb_symbol->accept(*this);

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    s4o.print(".,");

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  }

   193

  else if (type_is_complex)

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    wanted_variablegeneration = complextype_base_assignment_vg;

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  else

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    wanted_variablegeneration = assignment_vg;

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  symbol->accept(*this);

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  s4o.print(",");

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  wanted_variablegeneration = expression_vg;

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  print_check_function(type, value, fb_value);

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  if (type_is_complex) {

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    s4o.print(",");

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    wanted_variablegeneration = complextype_suffix_vg;

   205

    symbol->accept(*this);

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  }

   207

  s4o.print(")");

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  wanted_variablegeneration = expression_vg;

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  return NULL;

   210

}

   211

   212

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

   213

/* B 1.3.3 - Derived data types */

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

   215

   216

/*  signed_integer DOTDOT signed_integer */

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void *visit(subrange_c *symbol) {

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  switch (wanted_casegeneration) {

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    case subrange_cg:

   220

      s4o.print("__case_expression >= ");

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

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

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

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      break;

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    default:

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

   227

      break;

   228

  }

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  return NULL;

   230

}

   231

   232

/* ARRAY '[' array_subrange_list ']' OF non_generic_type_name */

   233

void *visit(array_specification_c *symbol) {

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

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  return NULL;

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}

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

   239

/* B 1.4 - Variables */

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

   241

void *visit(symbolic_variable_c *symbol) {

   242

  unsigned int vartype;

   243

  switch (wanted_variablegeneration) {

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    case complextype_base_assignment_vg:

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    case assignment_vg:

   246

      this->print_variable_prefix();

   247

      s4o.print(",");

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

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      break;

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    case complextype_base_vg:

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      generate_c_base_c::visit(symbol);

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      break;

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    case complextype_suffix_vg:

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      break;

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    default:

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      if (this->is_variable_prefix_null()) {

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        vartype = search_varfb_instance_type->get_vartype(symbol);

   258

        if (wanted_variablegeneration == fparam_output_vg) {

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          s4o.print("&(");

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          generate_c_base_c::visit(symbol);

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          s4o.print(")");

   262

        }

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        else {

   264

          generate_c_base_c::visit(symbol);

   265

        }

   266

      }

   267

      else

   268

        print_getter(symbol);

   269

      break;

   270

  }

   271

  return NULL;

   272

}

   273

   274

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

   275

/* 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");

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

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

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  if (this->is_variable_prefix_null()) {

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    if (wanted_variablegeneration != fparam_output_vg)

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	  s4o.print("*(");

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  }

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  else {

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    switch (wanted_variablegeneration) {

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      case expression_vg:

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  	    s4o.print(GET_LOCATED);

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  	    s4o.print("(");

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  	    break;

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      case fparam_output_vg:

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        s4o.print(GET_LOCATED_BY_REF);

   294

        s4o.print("(");

   295

        break;

   296

      default:

   297

        break;

   298

    }

   299

  }

   300

  this->print_variable_prefix();

   301

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

   302

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

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	  wanted_variablegeneration != assignment_vg)

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    s4o.print(")");

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  return NULL;

   306

}

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

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/* B.1.4.2   Multi-element Variables */

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

   311

   312

// SYM_REF2(structured_variable_c, record_variable, field_selector)

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void *visit(structured_variable_c *symbol) {

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  TRACE("structured_variable_c");

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  switch (wanted_variablegeneration) {

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    case complextype_base_vg:

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    case complextype_base_assignment_vg:

   318

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

   319

      break;

   320

    case complextype_suffix_vg:

   321

    case assignment_vg:

   322

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

   323

      s4o.print(".");

   324

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

   325

      break;

   326

    default:

   327

      if (this->is_variable_prefix_null()) {

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

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    	s4o.print(".");

   330

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

   331

      }

   332

      else

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    	print_getter(symbol);

   334

      break;

   335

  }

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  return NULL;

   337

}

   338

   339

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

   340

//SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

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void *visit(array_variable_c *symbol) {

   342

  switch (wanted_variablegeneration) {

   343

    case complextype_base_vg:

   344

    case complextype_base_assignment_vg:

   345

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

   346

      break;

   347

    case complextype_suffix_vg:

   348

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

   349

   350

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

   351

      if (current_array_type == NULL) ERROR;

   352

   353

      s4o.print(".table");

   354

      wanted_variablegeneration = expression_vg;

   355

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

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      wanted_variablegeneration = complextype_suffix_vg;

   357

   358

      current_array_type = NULL;

   359

      break;

   360

    default:

   361

      if (this->is_variable_prefix_null()) {

   362

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

   363

   364

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

   365

    	if (current_array_type == NULL) ERROR;

   366

   367

    	s4o.print(".table");

   368

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

   369

   370

        current_array_type = NULL;

   371

      }

   372

      else

   373

    	print_getter(symbol);

   374

      break;

   375

  }

   376

  return NULL;

   377

}

   378

   379

/* subscript_list ',' subscript */

   380

void *visit(subscript_list_c *symbol) {

   381

  array_dimension_iterator_c* array_dimension_iterator = new array_dimension_iterator_c(current_array_type);

   382

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

   383

    symbol_c* dimension = array_dimension_iterator->next();

   384

	if (dimension == NULL) ERROR;

   385

   386

	s4o.print("[(");

   387

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

   388

    s4o.print(") - (");

   389

    dimension->accept(*this);

   390

    s4o.print(")]");

   391

  }

   392

  delete array_dimension_iterator;

   393

  return NULL;

   394

}

   395

   396

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

   397

/* B 1.4.3 - Declaration & Initialisation */

   398

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

   399

   400

/* helper symbol for structure_initialization */

   401

/* structure_element_initialization_list ',' structure_element_initialization */

   402

void *visit(structure_element_initialization_list_c *symbol) {

   403

  generate_c_structure_initialization_c *structure_initialization = new generate_c_structure_initialization_c(&s4o);

   404

  structure_initialization->init_structure_default(this->current_param_type);

   405

  structure_initialization->init_structure_values(symbol);

   406

  delete structure_initialization;

   407

  return NULL;

   408

}

   409

   410

/* helper symbol for array_initialization */

   411

/* array_initial_elements_list ',' array_initial_elements */

   412

void *visit(array_initial_elements_list_c *symbol) {

   413

  generate_c_array_initialization_c *array_initialization = new generate_c_array_initialization_c(&s4o);

   414

  array_initialization->init_array_size(this->current_param_type);

   415

  array_initialization->init_array_values(symbol);

   416

  delete array_initialization;

   417

  return NULL;

   418

}

   419

   420

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

   421

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

   422

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

   423

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

   424

/* B 3.1 - Expressions */

   425

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

   426

void *visit(or_expression_c *symbol) {

   427

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

   428

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

   429

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

   430

      ERROR;

   431

  if (search_expression_type->is_bool_type(left_type))

   432

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

   433

  if (search_expression_type->is_binary_type(left_type))

   434

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

   435

  ERROR;

   436

  return NULL;

   437

}

   438

   439

void *visit(xor_expression_c *symbol) {

   440

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

   441

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

   442

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

   443

      ERROR;

   444

  if (search_expression_type->is_bool_type(left_type)) {

   445

    s4o.print("(");

   446

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

   447

    s4o.print(" && !");

   448

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

   449

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

   450

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

   451

    s4o.print(" && ");

   452

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

   453

    s4o.print(")");

   454

    return NULL;

   455

  }

   456

  if (search_expression_type->is_binary_type(left_type))

   457

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

   458

  ERROR;

   459

  return NULL;

   460

}

   461

   462

void *visit(and_expression_c *symbol) {

   463

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

   464

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

   465

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

   466

      ERROR;

   467

  if (search_expression_type->is_bool_type(left_type))

   468

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

   469

  if (search_expression_type->is_binary_type(left_type))

   470

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

   471

  ERROR;

   472

  return NULL;

   473

}

   474

   475

void *visit(equ_expression_c *symbol) {

   476

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

   477

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

   478

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

   479

      ERROR;

   480

  if (search_expression_type->is_time_type(left_type) ||

   481

      search_expression_type->is_string_type(left_type))

   482

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

   483

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

   484

}

   485

   486

void *visit(notequ_expression_c *symbol) {

   487

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

   488

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

   489

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

   490

      ERROR;

   491

  if (search_expression_type->is_time_type(left_type) ||

   492

      search_expression_type->is_string_type(left_type))

   493

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

   494

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

   495

}

   496

   497

void *visit(lt_expression_c *symbol) {

   498

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

   499