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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) 2009-2012  Mario de Sousa (msousa@fe.up.pt)

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 *  Copyright (C) 2012       Manuele Conti (manuele.conti@sirius-es.it)

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 *  Copyright (C) 2012       Matteo Facchinetti (matteo.facchinetti@sirius-es.it)

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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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 */

    25

    26

/*

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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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/* TODO - things yet not checked by this data type checker...

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 *

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 * - check variable declarations

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 * - check data type declarations

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 * - check inside configurations (variable declarations)

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 * - check SFC code

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 * - must fix S and R IL functions (includes potientialy fixing stage4 code!) 

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 */

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/* NOTE: The algorithm implemented here assumes that flow control analysis has already been completed!

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 *       BEFORE running this visitor, be sure to CALL the flow_control_analysis_c visitor!

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 */

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    49

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/*

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 *  Fill the candidate datatype list for all symbols that may legally 'have' a data type (e.g. variables, literals, function calls, expressions, etc.)

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 * 

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 *  The candidate datatype list will be filled with a list of all the data types that expression may legally take.

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 *  For example, the very simple literal '0' (as in foo := 0), may represent a:

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 *    BOOL, BYTE, WORD, DWORD, LWORD, USINT, SINT, UINT, INT, UDINT, DINT, ULINT, LINT (as well as the SAFE versions of these data tyes too!)

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 *

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 * WARNING: This visitor class starts off by building a map of all enumeration constants that are defined in the source code (i.e. a library_c symbol),

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 *          and this map is later used to determine the datatpe of each use of an enumeration constant. By implication, the fill_candidate_datatypes_c 

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 *          visitor class will only work corretly if it is asked to visit a symbol of class library_c!!

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 */

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#include <../main.hh>         /* required for UINT64_MAX, INT64_MAX, INT64_MIN, ... */

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#include "fill_candidate_datatypes.hh"

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#include "datatype_functions.hh"

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#include <typeinfo>

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#include <list>

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#include <string>

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#include <string.h>

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#include <strings.h>

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#define GET_CVALUE(dtype, symbol)             ((symbol)->const_value._##dtype.value)

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#define VALID_CVALUE(dtype, symbol)           (symbol_c::cs_const_value == (symbol)->const_value._##dtype.status)

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#define IS_OVERFLOW(dtype, symbol)            (symbol_c::cs_overflow == (symbol)->const_value._##dtype.status)

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/* set to 1 to see debug info during execution */

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static int debug = 0;

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

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/*                                                   */

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/*  A small helper class...                          */

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/*                                                   */

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

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/* Add to the global_enumerated_value_symtable the global enum value constants, i.e. the enum constants used in the enumerated

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 * datatypes that are defined inside a TYPE ... END_TYPE declaration.

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 */

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/* NOTE: we do not store any NULL values in this symbol table, so we can safely use NULL and the null value. */

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symbol_c null_enumvalue_symbol; /* cannot be static, so it may be used in the template!! */

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typedef dsymtable_c<symbol_c *, &null_enumvalue_symbol> enumerated_value_symtable_t;

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static enumerated_value_symtable_t global_enumerated_value_symtable;

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class populate_globalenumvalue_symtable_c: public iterator_visitor_c {

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  private:

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    symbol_c *current_enumerated_type;

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  public:

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     populate_globalenumvalue_symtable_c(void) {current_enumerated_type = NULL;};

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    ~populate_globalenumvalue_symtable_c(void) {}

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  public:

   108

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

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  /* B.1 - Common elements */

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

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

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  /* B.1.3 - Data types */

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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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  /*  enumerated_type_name ':' enumerated_spec_init */

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  void *visit(enumerated_type_declaration_c *symbol) {

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  //current_enumerated_type = symbol->enumerated_type_name;

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    current_enumerated_type = symbol;

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

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    current_enumerated_type = NULL;

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    return NULL;

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  }

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  /* enumerated_specification ASSIGN enumerated_value */

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  void *visit(enumerated_spec_init_c *symbol) {

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

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  }

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  /* [enumerated_type_name '#'] identifier */

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  void *visit(enumerated_value_c *symbol) {

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    if (current_enumerated_type == NULL) ERROR;

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

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    enumerated_value_symtable_t::iterator lower = global_enumerated_value_symtable.lower_bound(symbol->value);

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    enumerated_value_symtable_t::iterator upper = global_enumerated_value_symtable.upper_bound(symbol->value);

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    for (; lower != upper; lower++)

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      if (lower->second == current_enumerated_type) {

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        /*  The same identifier is used more than once as an enumerated value/constant inside the same enumerated datat type! */

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        return NULL; /* No need to insert it! It is already in the table! */

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      }

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

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    return NULL;

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  }

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   148

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

   149

  /* B.1.5 - Program organization units */

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

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  /* B 1.5.1 - Functions */

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  void *visit(function_declaration_c *symbol) {return NULL;}

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  /* B 1.5.2 - Function Blocks */

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  void *visit(function_block_declaration_c *symbol) {return NULL;}

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  /* B 1.5.3 - Programs */

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  void *visit(program_declaration_c *symbol) {return NULL;}

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}; /* populate_globalenumvalue_symtable_c */

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static populate_globalenumvalue_symtable_c populate_globalenumvalue_symtable;

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   162

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

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/*                                                   */

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/*  A small helper class...                          */

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/*                                                   */

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

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/* Add to the local_enumerated_value_symtable the local enum value constants */

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/* Notes:

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 * Some enumerations are 

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 *   (A) declared anonymously inside a VAR ... END_VAR declaration

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 *       (e.g. VAR enum_var : (enumvalue1, enumvalue2); END_VAR)

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 *  while others are 

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 *   (B) declared (with a name) inside a TYPE .. END_TYPE declaration.

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 *

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 *  Values in (A) are added to the enumerated_value_symtable in absyntaxt_utils.cc.

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 *  Values in (B) are only in scope inside the POU with the VAR END_VAR declaration.

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 *

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 * This class will add the enum values in (B) to the local_enumerated_value_symtable.

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 *

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 * If a locally defined enum value is identical to another locally defined enum_value, a 

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 *  duplicate entry is created.

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 *  However, if a locally defined enum value is identical to another globally defined enum_value, the

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 *  corresponding entry in local_enumerated_value_symtable is also set to the local datatype.

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 *  This is because anonynous locally feined enum datatypes are anonymous, and its enum values cannot therefore

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 *  be disambiguated using EnumType#enum_value (since the enum type does not have a name, it is anonymous!).

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 *  For this reason we implement the semantics where locally defined enum values, when in scope, will 'cover'

   189

 *  the globally defined enum value with the same name/identifier.

   190

 *  For example:

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 *

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 *  TYPE  GlobalEnumT: (xxx1, xxx2, xxx3) END_TYPE

   193

 * 

   194

 *   FUNCTION_BLOCK FOO

   195

 *    VAR_INPUT

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 *       GlobalEnumVar: GlobalEnumT;

   197

 *      LocalEnumVar : (xxx1, yyy2, yyy3);

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 *     END_VAR

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 *     LocalEnumVar  := xxx1;   <-- We consider it OK!!!     xxx1 will reference the anonymous type used for LocalEnumVar

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 *     GlobalEnumVar := xxx1;   <-- We consider it an error. xxx1 will reference the anonymous type used for LocalEnumVar

   201

 *     GlobalEnumVar := GlobalEnumT#xxx1;

   202

 *     END_FUNCTION_BLOCK

   203

 */

   204

   205

static enumerated_value_symtable_t local_enumerated_value_symtable;

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   207

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class populate_localenumvalue_symtable_c: public iterator_visitor_c {

   209

  private:

   210

    symbol_c *current_enumerated_type;

   211

   212

  public:

   213

     populate_localenumvalue_symtable_c(void) {current_enumerated_type = NULL;};

   214

    ~populate_localenumvalue_symtable_c(void) {}

   215

   216

  public:

   217

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

   218

  /* B.1 - Common elements */

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

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

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  /* B.1.3 - Data types */

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

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

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  /* B 1.3.3 - Derived data types */

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

   226

  /*  TYPE type_declaration_list END_TYPE */

   227

  void *visit(data_type_declaration_c *symbol) {return NULL;} // do not visit the type declarations!!

   228

   229

  /* enumerated_specification ASSIGN enumerated_value */

   230

  void *visit(enumerated_spec_init_c *symbol) {

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    current_enumerated_type = symbol;

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

   233

    /* DO NOT visit the symbol->enumerated_value   !!! */

   234

    current_enumerated_type = NULL;

   235

    return NULL;

   236

  }

   237

   238

  /* [enumerated_type_name '#'] identifier */

   239

  void *visit(enumerated_value_c *symbol) {

   240

    /* if the enumerated_value_c is not inside a enumerated_spec_init_c (e.g. used as the inital value of a variable), we simply return */

   241

    if (current_enumerated_type == NULL) return NULL;  

   242

    /* this is really an ERROR! The initial value may use the syntax NUM_TYPE#enum_value, but in that case we should have return'd in the above statement !! */

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

   244

   245

    enumerated_value_symtable_t::iterator lower = local_enumerated_value_symtable.lower_bound(symbol->value);

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    enumerated_value_symtable_t::iterator upper = local_enumerated_value_symtable.upper_bound(symbol->value);

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    for (; lower != upper; lower++)

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      if (lower->second == current_enumerated_type) {

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        /*  The same identifier is used more than once as an enumerated value/constant inside the same enumerated datat type! */

   250

        return NULL; /* No need to insert it! It is already in the table! */

   251

      }

   252

   253

    /* add it to the local symbol table. */

   254

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

   255

    return NULL;

   256

  }

   257

}; // class populate_enumvalue_symtable_c

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static populate_localenumvalue_symtable_c populate_enumvalue_symtable;

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

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/*                                                   */

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/*  Main  FILL candidate datatypes algorithm...      */

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/*                                                   */

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

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fill_candidate_datatypes_c::fill_candidate_datatypes_c(symbol_c *ignore) {

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	il_operand = NULL;

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	prev_il_instruction = NULL;

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	search_var_instance_decl = NULL;

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	current_enumerated_spec_type = NULL;

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	current_scope = NULL;

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}

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fill_candidate_datatypes_c::~fill_candidate_datatypes_c(void) {

   280

}

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symbol_c *fill_candidate_datatypes_c::widening_conversion(symbol_c *left_type, symbol_c *right_type, const struct widen_entry widen_table[]) {

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	int k;

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	/* find a widening table entry compatible */

   291

	for (k = 0; NULL != widen_table[k].left;  k++)

   292

		if ((typeid(*left_type) == typeid(*widen_table[k].left)) && (typeid(*right_type) == typeid(*widen_table[k].right)))

   293

                      return widen_table[k].result;

   294

	return NULL;

   295

}

   296

   297

   298

/* add a data type to a candidate data type list, while guaranteeing no duplicate entries! */

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/* Returns true if it really did add the datatype to the list, or false if it was already present in the list! */

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bool fill_candidate_datatypes_c::add_datatype_to_candidate_list(symbol_c *symbol, symbol_c *datatype) {

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  /* If it is an invalid data type, do not insert!

   302

   * NOTE: it reduces overall code size to do this test here, instead of doing every time before calling the add_datatype_to_candidate_list() function. 

   303

   */

   304

  if (!get_datatype_info_c::is_type_valid(datatype)) /* checks for NULL and invalid_type_name_c */

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    return false;

   306

   307

  if (search_in_candidate_datatype_list(datatype, symbol->candidate_datatypes) >= 0) 

   308

    /* already in the list, Just return! */

   309

    return false;

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  /* not yet in the candidate data type list, so we insert it now! */

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  symbol->candidate_datatypes.push_back(datatype);

   313

  return true;

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}

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bool fill_candidate_datatypes_c::add_2datatypes_to_candidate_list(symbol_c *symbol, symbol_c *datatype1, symbol_c *datatype2) {

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  add_datatype_to_candidate_list(symbol, datatype1);

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  add_datatype_to_candidate_list(symbol, datatype2);

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  return true;

   321

}

   322

   323

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void fill_candidate_datatypes_c::remove_incompatible_datatypes(symbol_c *symbol) {

   326

  #ifdef __REMOVE__

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    #error __REMOVE__ macro already exists. Choose another name!

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  #endif

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  #define __REMOVE__(datatype)\

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      remove_from_candidate_datatype_list(&get_datatype_info_c::datatype,       symbol->candidate_datatypes);\

   331

      remove_from_candidate_datatype_list(&get_datatype_info_c::safe##datatype, symbol->candidate_datatypes);

   332

   333

  {/* Remove unsigned data types */

   334

    uint64_t value = 0;

   335

    if (VALID_CVALUE( uint64, symbol)) value = GET_CVALUE(uint64, symbol);

   336

    if (IS_OVERFLOW ( uint64, symbol)) value = (uint64_t)UINT32_MAX + (uint64_t)1;

   337

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    if (value > 1          )          {__REMOVE__(bool_type_name);}

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    if (value > UINT8_MAX  )          {__REMOVE__(usint_type_name);  __REMOVE__( byte_type_name);}

   340

    if (value > UINT16_MAX )          {__REMOVE__( uint_type_name);  __REMOVE__( word_type_name);}

   341

    if (value > UINT32_MAX )          {__REMOVE__(udint_type_name);  __REMOVE__(dword_type_name);}

   342

    if (IS_OVERFLOW( uint64, symbol)) {__REMOVE__(ulint_type_name);  __REMOVE__(lword_type_name);}

   343

  }

   344

   345

  {/* Remove signed data types */

   346

    int64_t value = 0;

   347

    if (VALID_CVALUE(  int64, symbol)) value = GET_CVALUE(int64, symbol);

   348

    if (IS_OVERFLOW (  int64, symbol)) value = (int64_t)INT32_MAX + (int64_t)1;

   349

   350

    if ((value <  INT8_MIN) || (value >  INT8_MAX)) {__REMOVE__(sint_type_name);}

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    if ((value < INT16_MIN) || (value > INT16_MAX)) {__REMOVE__( int_type_name);}

   352

    if ((value < INT32_MIN) || (value > INT32_MAX)) {__REMOVE__(dint_type_name);}

   353

    if (IS_OVERFLOW( int64, symbol))                {__REMOVE__(lint_type_name);}

   354

  }

   355

   356

  {/* Remove floating point data types */

   357

    real64_t value = 0;

   358

    if (VALID_CVALUE( real64, symbol)) value = GET_CVALUE(real64, symbol);

   359

    if (IS_OVERFLOW ( real64, symbol)) value = (real64_t)REAL32_MAX + (real64_t)1;

   360

    if (value >  REAL32_MAX )         {__REMOVE__( real_type_name);}

   361

    if (value < -REAL32_MAX )         {__REMOVE__( real_type_name);}

   362

    if (IS_OVERFLOW( real64, symbol)) {__REMOVE__(lreal_type_name);}

   363

  }

   364

  #undef __REMOVE__

   365

}

   366

   367

   368

/* returns true if compatible function/FB invocation, otherwise returns false */

   369

/* Assumes that the candidate_datatype lists of all the parameters being passed haved already been filled in */

   370

/*

   371

 * All parameters being passed to the called function MUST be in the parameter list to which f_call points to!

   372

 * This means that, for non formal function calls in IL, de current (default value) must be artificially added to the

   373

 * beginning of the parameter list BEFORE calling handle_function_call().

   374

 */

   375

bool fill_candidate_datatypes_c::match_nonformal_call(symbol_c *f_call, symbol_c *f_decl) {

   376

	symbol_c *call_param_value,  *param_datatype;

   377

	identifier_c *param_name;

   378

	function_param_iterator_c       fp_iterator(f_decl);

   379

	function_call_param_iterator_c fcp_iterator(f_call);

   380

	int extensible_parameter_highest_index = -1;

   381

	unsigned int i;

   382

   383

	/* Iterating through the non-formal parameters of the function call */

   384

	while((call_param_value = fcp_iterator.next_nf()) != NULL) {

   385

		/* Iterate to the next parameter of the function being called.

   386

		 * Get the name of that parameter, and ignore if EN or ENO.

   387

		 */

   388

		do {

   389

			param_name = fp_iterator.next();

   390

			/* If there is no other parameter declared, then we are passing too many parameters... */

   391

			if(param_name == NULL) return false;

   392

		} while ((strcmp(param_name->value, "EN") == 0) || (strcmp(param_name->value, "ENO") == 0));

   393

   394

		/* Get the parameter type */

   395

		param_datatype = base_type(fp_iterator.param_type());

   396

   397

		/* check whether one of the candidate_data_types of the value being passed is the same as the param_type */

   398

		if (search_in_candidate_datatype_list(param_datatype, call_param_value->candidate_datatypes) < 0)

   399

			return false; /* return false if param_type not in the list! */

   400

	}

   401

	/* call is compatible! */

   402

	return true;

   403

}

   404

   405

   406

   407

/* returns true if compatible function/FB invocation, otherwise returns false */

   408

/* Assumes that the candidate_datatype lists of all the parameters being passed haved already been filled in */

   409

bool fill_candidate_datatypes_c::match_formal_call(symbol_c *f_call, symbol_c *f_decl, symbol_c **first_param_datatype) {

   410

	symbol_c *call_param_value, *call_param_name, *param_datatype;

   411

	symbol_c *verify_duplicate_param;

   412

	identifier_c *param_name;

   413

	function_param_iterator_c       fp_iterator(f_decl);

   414

	function_call_param_iterator_c fcp_iterator(f_call);

   415

	int extensible_parameter_highest_index = -1;

   416

	identifier_c *extensible_parameter_name;

   417

	unsigned int i;

   418

	bool is_first_param = true;

   419

   420

	/* Iterating through the formal parameters of the function call */

   421

	while((call_param_name = fcp_iterator.next_f()) != NULL) {

   422

		/* Obtaining the value being passed in the function call */

   423

		call_param_value = fcp_iterator.get_current_value();

   424

		/* the following should never occur. If it does, then we have a bug in our code... */

   425

		if (NULL == call_param_value) ERROR;

   426

   427

		/* Obtaining the assignment direction:  := (assign_in) or => (assign_out) */

   428

		function_call_param_iterator_c::assign_direction_t call_param_dir = fcp_iterator.get_assign_direction();

   429

   430

		/* Checking if there are duplicated parameter values */

   431

		verify_duplicate_param = fcp_iterator.search_f(call_param_name);

   432

		if(verify_duplicate_param != call_param_value)

   433

			return false;

   434

   435

		/* Obtaining the type of the value being passed in the function call */

   436

		std::vector <symbol_c *>&call_param_types = call_param_value->candidate_datatypes;

   437

   438

		/* Find the corresponding parameter in function declaration */

   439

		param_name = fp_iterator.search(call_param_name);

   440

		if(param_name == NULL) return false;

   441

		/* Get the parameter data type */

   442

		param_datatype = base_type(fp_iterator.param_type());

   443

		/* Get the parameter direction: IN, OUT, IN_OUT */

   444

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

   445

   446

		/* check whether direction (IN, OUT, IN_OUT) and assignment types (:= , =>) are compatible !!! */

   447

		if          (function_call_param_iterator_c::assign_in  == call_param_dir) {

   448

			if ((function_param_iterator_c::direction_in    != param_dir) &&

   449

			    (function_param_iterator_c::direction_inout != param_dir))

   450

				return false;

   451

		} else if   (function_call_param_iterator_c::assign_out == call_param_dir) {

   452

			if ((function_param_iterator_c::direction_out   != param_dir))

   453

				return false;

   454

		} else ERROR;

   455

   456

		/* check whether one of the candidate_data_types of the value being passed is the same as the param_type */

   457

		if (search_in_candidate_datatype_list(param_datatype, call_param_types) < 0)

   458

			return false; /* return false if param_type not in the list! */

   459

   460

		/* If this is the first parameter, then copy the datatype to *first_param_datatype */

   461

		if (is_first_param)

   462

			if (NULL != first_param_datatype)

   463

				*first_param_datatype = param_datatype;

   464

		is_first_param = false;

   465

	}

   466

	/* call is compatible! */

   467

	return true;

   468

}

   469

   470

   471

   472

   473

/* Handle a generic function call!

   474

 * Assumes that the parameter_list containing the values being passed in this function invocation

   475

 * has already had all the candidate_datatype lists filled in!

   476

 *

   477

 * All parameters being passed to the called function MUST be in the parameter list to which f_call points to!

   478

 * This means that, for non formal function calls in IL, de current (default value) must be artificially added to the

   479

 * beginning of the parameter list BEFORE calling handle_function_call().

   480

 */

   481

/*

   482

typedef struct {

   483

  symbol_c *function_name,

   484

  symbol_c *nonformal_operand_list,

   485

  symbol_c *   formal_operand_list,

   486

   487

  std::vector <symbol_c *> &candidate_functions,  

   488

  symbol_c &*called_function_declaration,

   489

  int      &extensible_param_count

   490

} generic_function_call_t;

   491

*/

   492

/*

   493

void narrow_candidate_datatypes_c::narrow_function_invocation(symbol_c *fcall, generic_function_call_t fcall_data) {

   494

void *fill_candidate_datatypes_c::handle_function_call(symbol_c *f_call, symbol_c *function_name, invocation_type_t invocation_type,

   495

                                                       std::vector <symbol_c *> *candidate_datatypes,

   496

                                                       std::vector <symbol_c *> *candidate_functions) {