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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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 *

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 *  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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 *

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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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/*

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 * An IEC 61131-3 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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/*

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 * Array dimension iterator.

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 * Iterate through the dimensions of array specification.

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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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/* Given a array_specification_c, iterate through

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 * each subrange, returning the symbol of each subrange

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 * ...array_dimension_iterator_c

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 */

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#include "array_dimension_iterator.hh"

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

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//#define DEBUG

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#ifdef DEBUG

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

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#else

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#define TRACE(classname)

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#endif

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void* array_dimension_iterator_c::iterate_list(list_c *list) {

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  void *res;

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

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    res = list->elements[i]->accept(*this);

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    if (res != NULL)

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        return res;

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  }

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  return NULL;

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}

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/* start off at the first case element once again... */

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void array_dimension_iterator_c::reset(void) {

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  current_array_dimension = NULL;

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}

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/* initialize the iterator object.

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 * We must be given a reference to a array_specification_c that will be analyzed...

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 */

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array_dimension_iterator_c::array_dimension_iterator_c(symbol_c *symbol) {

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  /* do some consistency check... */

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  /* NOTE: We comment out the consistency check so the compiler does not bork when it encounters buggy source code.

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   *        e.g. Code that handles a non array variable as an array!

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   *               VAR  v1, v2: int; END_VAR

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   *               v1 := v2[33, 45];

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   *       The above error will be caught by the datatype checking algorithms!

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   */

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  array_spec_init_c    * array_spec_init = dynamic_cast<array_spec_init_c    *>(symbol); 

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  if (NULL != array_spec_init)    symbol = array_spec_init->array_specification;

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  array_specification_c* array_spec      = dynamic_cast<array_specification_c*>(symbol);

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  // if (NULL == array_spec) ERROR;

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  /* OK. Now initialize this object... */

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  this->array_specification = array_spec; // Set to array_spec and not symbol => will be NULL if not an array_specification_c* !!

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  reset();

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}

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/* Skip to the next subrange. After object creation,

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 * the object references on subrange _before_ the first, so

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 * this function must be called once to get the object to

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 * reference the first subrange...

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 *

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 * Returns the subrange symbol!

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 */

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subrange_c *array_dimension_iterator_c::next(void) {

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  if (NULL == array_specification) return NULL; /* The source code probably has a bug which will be caught somewhere else! */

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  void *res = array_specification->accept(*this);

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  if (NULL == res)                 return NULL;

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  return current_array_dimension;

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}

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

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/* B 1.3.3 - Derived data types */

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

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/*  signed_integer DOTDOT signed_integer */

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void *array_dimension_iterator_c::visit(subrange_c *symbol) {

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  if (current_array_dimension == symbol) {

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	current_array_dimension = NULL;

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  }

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  else if (current_array_dimension == NULL) {

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	current_array_dimension = symbol;

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	return symbol;

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  }

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  /* Not found! */

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  return NULL;

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}

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

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void *array_dimension_iterator_c::visit(array_specification_c *symbol) {

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

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}

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/* array_subrange_list ',' subrange */

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void *array_dimension_iterator_c::visit(array_subrange_list_c *symbol) {

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  return iterate_list(symbol);

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}

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