mario@181: /*
msousa@265:  *  matiec - a compiler for the programming languages defined in IEC 61131-3
msousa@265:  *
msousa@265:  *  Copyright (C) 2003-2011  Mario de Sousa (msousa@fe.up.pt)
Edouard@279:  *  Copyright (C) 2007-2011  Laurent Bessard and Edouard Tisserant
msousa@265:  *
msousa@265:  *  This program is free software: you can redistribute it and/or modify
msousa@265:  *  it under the terms of the GNU General Public License as published by
msousa@265:  *  the Free Software Foundation, either version 3 of the License, or
msousa@265:  *  (at your option) any later version.
msousa@265:  *
msousa@265:  *  This program is distributed in the hope that it will be useful,
msousa@265:  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
msousa@265:  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
msousa@265:  *  GNU General Public License for more details.
msousa@265:  *
msousa@265:  *  You should have received a copy of the GNU General Public License
msousa@265:  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
msousa@265:  *
mario@181:  *
mario@181:  * This code is made available on the understanding that it will not be
mario@181:  * used in safety-critical situations without a full and competent review.
mario@181:  */
mario@181: 
mario@181: /*
msousa@265:  * An IEC 61131-3 compiler.
mario@181:  *
mario@181:  * Based on the
mario@181:  * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
mario@181:  *
mario@181:  */
mario@181: 
mario@181: /*
mario@181:  * Determine the default initial value of a type declaration.
mario@181:  *
mario@181:  * This is part of the 4th stage that generates
mario@181:  * a c++ source program equivalent to the IL and ST
mario@181:  * code.
mario@181:  */
mario@181: /* Given a type definition declration, determine its default
mario@181:  * initial value. Note that types based on other types
mario@181:  * may have to iterate through each type it is based on
mario@181:  * to determine the initial value.
mario@181:  * E.g.
mario@181:  *  TYPE
mario@181:  *    A_t : INT := 10;
mario@181:  *    B_t : A_t := 20;
mario@181:  *    C_t : B_t;
mario@181:  *    D_t : C_t := 40;
mario@181:  *  END_TYPE
mario@181:  * Where the default initial value for C_t is 20!
mario@181:  */
mario@181: /* NOTE: The main program only needs one instance of
mario@181:  *       this class of object. This class
mario@181:  *       is therefore a singleton.
mario@181:  */
mario@181: 
mario@181: 
mario@181: #include "absyntax_utils.hh"
mario@181: 
mario@181: //#define DEBUG
mario@181: #ifdef DEBUG
mario@181: #define TRACE(classname) printf("\n____%s____\n",classname);
mario@181: #else
mario@181: #define TRACE(classname)
mario@181: #endif
mario@181: 
mario@181: 
mario@181: type_initial_value_c *type_initial_value_c::instance(void) {
mario@181:   if (_instance != NULL)
mario@181:     return _instance;
mario@181: 
mario@181:   _instance = new type_initial_value_c;
mario@181: 
mario@181:   real_0 = new real_c("0");
mario@181:   integer_0 = new integer_c("0");
mario@181:   integer_1 = new integer_c("1");
mario@181:   bool_0 = new boolean_literal_c(new bool_type_name_c(),new boolean_false_c());
mario@181:   /* FIXME: Our current implementation only allows dates from 1970 onwards,
mario@181:    * but the standard defines the date 0001-01-01 as the default value
mario@181:    * for the DATE data type. Untill we fix our implementation, we use 1970-01-01
mario@181:    * as our default value!!
mario@181:    */
mario@181:     date_literal_0 =  new date_literal_c(integer_1, integer_1, integer_1);
mario@181:   date_literal_0 =  new date_literal_c(new integer_c("1970"), integer_1, integer_1);
mario@181:   daytime_literal_0 = new daytime_c(integer_0, integer_0, real_0);
msousa@257:   time_0 = new duration_c(new time_type_name_c(), NULL, new seconds_c(integer_0, NULL));  // T#0S
msousa@257:   date_0 = new date_c(new date_type_name_c(), date_literal_0);  //  D#0001-01-01
msousa@257:   tod_0 = new time_of_day_c(new tod_type_name_c(), daytime_literal_0);  //  TOD#00:00:00
msousa@257:   dt_0 = new date_and_time_c(new dt_type_name_c(), date_literal_0, daytime_literal_0);  //  DT#0001-01-01-00:00:00
mario@181:   string_0  = new single_byte_character_string_c("''");
mario@181:   wstring_0 = new double_byte_character_string_c("\"\"");
mario@181: 
mario@181:   return _instance;
mario@181: }
mario@181: 
mario@181: type_initial_value_c::type_initial_value_c(void) {}
mario@181: 
mario@181: 
mario@181: 
mario@181: symbol_c *type_initial_value_c::get(identifier_c *type_name) {
mario@181:   TRACE("type_initial_value_c::get(): called ");
mario@181:   return (symbol_c *)type_name->accept(*this);
mario@181: }
mario@181: 
mario@181: 
mario@181: 
mario@181: 
mario@181: void *type_initial_value_c::handle_type_spec(symbol_c *base_type_name, symbol_c *type_spec_init) {
mario@181:   if (type_spec_init != NULL)
mario@181:      return type_spec_init;
mario@181:    /* no initial value specified, so we return
mario@181:    * the initial value of the type this type is based on...
mario@181:     */
mario@181:   return base_type_name->accept(*this);
mario@181: }
mario@181: 
mario@181: 
mario@181: 
mario@181: void *type_initial_value_c::visit(identifier_c *type_name) {
mario@181:   /* look up the type declaration... */
mario@181:   symbol_c *type_decl = type_symtable.find_value(type_name);
mario@181:   if (type_decl == type_symtable.end_value())
mario@181:     /* Type declaration not found!! */
mario@181:     /* NOTE: Variables declared out of function block 'data types',
mario@181:      *    for eg:  VAR  timer: TON; END_VAR
mario@181:      * do not have a default value, so (TON) will never be found in the
mario@181:      * type symbol table. This means we cannot simply consider this
mario@181:      * an error and abort, but must rather return a NULL.
mario@181:      */
mario@181:      return NULL;
mario@181: 
mario@181:   return type_decl->accept(*this);
mario@181: }
mario@181: 
mario@181: /***********************************/
mario@181: /* B 1.3.1 - Elementary Data Types */
mario@181: /***********************************/
msousa@257: void *type_initial_value_c::visit(time_type_name_c *symbol)         {return (void *)time_0;}
msousa@257: void *type_initial_value_c::visit(bool_type_name_c *symbol)         {return (void *)bool_0;}
msousa@257: void *type_initial_value_c::visit(sint_type_name_c *symbol)         {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(int_type_name_c *symbol)          {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(dint_type_name_c *symbol)         {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(lint_type_name_c *symbol)         {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(usint_type_name_c *symbol)        {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(uint_type_name_c *symbol)         {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(udint_type_name_c *symbol)        {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(ulint_type_name_c *symbol)        {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(real_type_name_c *symbol)         {return (void *)real_0;}
msousa@257: void *type_initial_value_c::visit(lreal_type_name_c *symbol)        {return (void *)real_0;}
msousa@257: void *type_initial_value_c::visit(date_type_name_c *symbol)         {return (void *)date_0;}
msousa@257: void *type_initial_value_c::visit(tod_type_name_c *symbol)          {return (void *)tod_0;}
msousa@257: void *type_initial_value_c::visit(dt_type_name_c *symbol)           {return (void *)dt_0;}
msousa@257: void *type_initial_value_c::visit(byte_type_name_c *symbol)         {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(word_type_name_c *symbol)         {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(dword_type_name_c *symbol)        {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(lword_type_name_c *symbol)        {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(string_type_name_c *symbol)       {return (void *)string_0;}
msousa@257: void *type_initial_value_c::visit(wstring_type_name_c *symbol)      {return (void *)wstring_0;}
msousa@257: 
msousa@257: void *type_initial_value_c::visit(safetime_type_name_c *symbol)     {return (void *)time_0;}
msousa@257: void *type_initial_value_c::visit(safebool_type_name_c *symbol)     {return (void *)bool_0;}
msousa@257: void *type_initial_value_c::visit(safesint_type_name_c *symbol)     {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safeint_type_name_c *symbol)      {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safedint_type_name_c *symbol)     {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safelint_type_name_c *symbol)     {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safeusint_type_name_c *symbol)    {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safeuint_type_name_c *symbol)     {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safeudint_type_name_c *symbol)    {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safeulint_type_name_c *symbol)    {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safereal_type_name_c *symbol)     {return (void *)real_0;}
msousa@257: void *type_initial_value_c::visit(safelreal_type_name_c *symbol)    {return (void *)real_0;}
msousa@257: void *type_initial_value_c::visit(safedate_type_name_c *symbol)     {return (void *)date_0;}
msousa@257: void *type_initial_value_c::visit(safetod_type_name_c *symbol)      {return (void *)tod_0;}
msousa@257: void *type_initial_value_c::visit(safedt_type_name_c *symbol)       {return (void *)dt_0;}
msousa@257: void *type_initial_value_c::visit(safebyte_type_name_c *symbol)     {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safeword_type_name_c *symbol)     {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safedword_type_name_c *symbol)    {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safelword_type_name_c *symbol)    {return (void *)integer_0;}
msousa@257: void *type_initial_value_c::visit(safestring_type_name_c *symbol)   {return (void *)string_0;}
msousa@257: void *type_initial_value_c::visit(safewstring_type_name_c *symbol)  {return (void *)wstring_0;}
mario@181: 
mario@181: /********************************/
mario@181: /* B 1.3.3 - Derived data types */
mario@181: /********************************/
mario@181: /*  simple_type_name ':' simple_spec_init */
mario@181: void *type_initial_value_c::visit(simple_type_declaration_c *symbol) {
mario@181:   return symbol->simple_spec_init->accept(*this);
mario@181: }
mario@181: /* simple_specification ASSIGN constant */
mario@181: void *type_initial_value_c::visit(simple_spec_init_c *symbol) {
mario@181:   return handle_type_spec(symbol->simple_specification, symbol->constant);
mario@181: }
mario@181: /*  subrange_type_name ':' subrange_spec_init */
mario@181: void *type_initial_value_c::visit(subrange_type_declaration_c *symbol) {
mario@181:   return symbol->subrange_spec_init->accept(*this);
mario@181: }
mario@181: /* subrange_specification ASSIGN signed_integer */
mario@181: void *type_initial_value_c::visit(subrange_spec_init_c *symbol) {
mario@181:   return handle_type_spec(symbol->subrange_specification, symbol->signed_integer);
mario@181: }
mario@181: /*  integer_type_name '(' subrange')' */
mario@181: void *type_initial_value_c::visit(subrange_specification_c *symbol) {
mario@181:  /* if no initial value explicitly given, then use the lowest value of the subrange */
mario@181:   if (symbol->subrange != NULL)
mario@181:     return symbol->subrange->accept(*this);
mario@181:   else
mario@181:     return symbol->integer_type_name->accept(*this);
mario@181: }
mario@181: /*  signed_integer DOTDOT signed_integer */
mario@181: void *type_initial_value_c::visit(subrange_c *symbol)	{return symbol->lower_limit;}
mario@181: /*  enumerated_type_name ':' enumerated_spec_init */
mario@181: void *type_initial_value_c::visit(enumerated_type_declaration_c *symbol) {
mario@181:   return symbol->enumerated_spec_init->accept(*this);
mario@181: }
mario@181: /* enumerated_specification ASSIGN enumerated_value */
mario@181: void *type_initial_value_c::visit(enumerated_spec_init_c *symbol) {
mario@181:   return handle_type_spec(symbol->enumerated_specification, symbol->enumerated_value);
mario@181: }
mario@181: /* helper symbol for enumerated_specification->enumerated_spec_init */
mario@181: /* enumerated_value_list ',' enumerated_value */
mario@181: void *type_initial_value_c::visit(enumerated_value_list_c *symbol) {
mario@181:  /* if no initial value explicitly given, then use the lowest value of the subrange */
mario@181:   return (void *)symbol->elements[0];
mario@181: }
mario@181: /* enumerated_type_name '#' identifier */
mario@181: // SYM_REF2(enumerated_value_c, type, value)
mario@181: void *type_initial_value_c::visit(enumerated_value_c *symbol)	{ERROR; return NULL;}
mario@181: /*  identifier ':' array_spec_init */
mario@181: void *type_initial_value_c::visit(array_type_declaration_c *symbol) {
mario@181:   return symbol->array_spec_init->accept(*this);
mario@181: }
mario@181: /* array_specification [ASSIGN array_initialization} */
mario@181: /* array_initialization may be NULL ! */
mario@181: void *type_initial_value_c::visit(array_spec_init_c *symbol) {
mario@181:   return handle_type_spec(symbol->array_specification, symbol->array_initialization);
mario@181: }
mario@181: /* ARRAY '[' array_subrange_list ']' OF non_generic_type_name */
mario@181: void *type_initial_value_c::visit(array_specification_c *symbol)	{
mario@181:   //symbol_c *init_value = (symbol_c *)symbol->non_generic_type_name->accept(*this);
mario@181: 
mario@181:   /* Now build a array_initial_elements_list_c list, and populate it
mario@181:    * with 1 element of the array_initial_elements_c class
mario@181:    */
mario@181:   /* The array_initial_elements_c will contain a reference to the init_value,
mario@181:    * and another constant representing the number of elements in the array.
mario@181:    * In essence, we are building the equivilant of the following ST/IL code:
mario@181:    *    New_array_t : ARRAY [1..30, 51..60] of INT := [40(XXX)];
mario@181:    * from the user given code
mario@181:    *    New_array_t : ARRAY [1..30, 51..60] of INT;
mario@181:    * and replacing XXX with the default initial value of INT.
mario@181:    */
mario@181:   /* now we need to determine the number of elements in the array... */
mario@181:   /* Easier said than done, as the array may have a list of subranges, as in the
mario@181:    * example given above!!
mario@181:    */
mario@181:   /* TODO !!!!!*/
mario@181:   /* For now, just assume an array with 1 element.
mario@181:    * I (Mario) want to finish off this part of the code before getting boged down
mario@181:    * in something else...
mario@181:    */
mario@181:   // NOTE: We are leaking memory, as the integer will never get free'd!!
mario@181:   //integer_c *integer = new integer_c("1");
mario@181:   // NOTE: We are leaking memory, as the array_initial_elements will never get free'd!!
mario@181:   //array_initial_elements_c *array_initial_elements = new array_initial_elements_c(integer, init_value);
mario@181:   // NOTE: We are leaking memory, as the array_initial_elements_list will never get free'd!!
mario@181:   array_initial_elements_list_c *array_initial_elements_list  = new array_initial_elements_list_c();
mario@181:   //array_initial_elements_list->add_element(array_initial_elements);
mario@181:   return array_initial_elements_list;
mario@181: }
mario@181: /* helper symbol for array_specification */
mario@181: /* array_subrange_list ',' subrange */
mario@181: void *type_initial_value_c::visit(array_subrange_list_c *symbol)	{ERROR; return NULL;}
mario@181: /* array_initialization:  '[' array_initial_elements_list ']' */
mario@181: /* helper symbol for array_initialization */
mario@181: /* array_initial_elements_list ',' array_initial_elements */
mario@181: void *type_initial_value_c::visit(array_initial_elements_list_c *symbol)	{ERROR; return NULL;}
mario@181: /* integer '(' [array_initial_element] ')' */
mario@181: /* array_initial_element may be NULL ! */
mario@181: void *type_initial_value_c::visit(array_initial_elements_c *symbol)	{ERROR; return NULL;}
mario@181: 
mario@181: 
mario@181: 
mario@181: /* TODO: from this point forward... */
mario@181: 
mario@181: /*  structure_type_name ':' structure_specification */
mario@181: void *type_initial_value_c::visit(structure_type_declaration_c *symbol) {return NULL;}
mario@181: /* structure_type_name ASSIGN structure_initialization */
mario@181: /* structure_initialization may be NULL ! */
mario@181: void *type_initial_value_c::visit(initialized_structure_c *symbol)	{
mario@181:   return handle_type_spec(symbol->structure_type_name, symbol->structure_initialization);
mario@181: }
mario@181: /* helper symbol for structure_declaration */
mario@181: /* structure_declaration:  STRUCT structure_element_declaration_list END_STRUCT */
mario@181: /* structure_element_declaration_list structure_element_declaration ';' */
mario@181: void *type_initial_value_c::visit(structure_element_declaration_list_c *symbol)	{
mario@181:   structure_element_initialization_list_c *structure_element_initialization_list = new structure_element_initialization_list_c();
mario@181:   return structure_element_initialization_list;
mario@181: }
mario@181: /*  structure_element_name ':' *_spec_init */
mario@181: void *type_initial_value_c::visit(structure_element_declaration_c *symbol)	{return NULL;}
mario@181: /* helper symbol for structure_initialization */
mario@181: /* structure_initialization: '(' structure_element_initialization_list ')' */
mario@181: /* structure_element_initialization_list ',' structure_element_initialization */
mario@181: void *type_initial_value_c::visit(structure_element_initialization_list_c *symbol)	{return NULL;}
mario@181: /*  structure_element_name ASSIGN value */
mario@181: void *type_initial_value_c::visit(structure_element_initialization_c *symbol)	{return NULL;}
mario@181: /*  string_type_name ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init */
mario@181: /*
mario@181:  * NOTE:
mario@181:  * (Summary: Contrary to what is expected, the
mario@181:  *           string_type_declaration_c is not used to store
mario@181:  *           simple string type declarations that do not include
mario@181:  *           size limits.
mario@181:  *           For e.g.:
mario@181:  *             str1_type: STRING := "hello!"
mario@181:  *           will be stored in a simple_type_declaration_c
mario@181:  *           instead of a string_type_declaration_c.
mario@181:  *           The following:
mario@181:  *             str2_type: STRING [64] := "hello!"
mario@181:  *           will be stored in a sring_type_declaration_c
mario@181:  *
mario@181:  *           Read on for why this is done...
mario@181:  * End Summary)
mario@181:  *
mario@181:  * According to the spec, the valid construct
mario@181:  * TYPE new_str_type : STRING := "hello!"; END_TYPE
mario@181:  * has two possible routes to type_declaration...
mario@181:  *
mario@181:  * Route 1:
mario@181:  * type_declaration: single_element_type_declaration
mario@181:  * single_element_type_declaration: simple_type_declaration
mario@181:  * simple_type_declaration: identifier ':' simple_spec_init
mario@181:  * simple_spec_init: simple_specification ASSIGN constant
mario@181:  * (shift:  identifier <- 'new_str_type')
mario@181:  * simple_specification: elementary_type_name
mario@181:  * elementary_type_name: STRING
mario@181:  * (shift: elementary_type_name <- STRING)
mario@181:  * (reduce: simple_specification <- elementary_type_name)
mario@181:  * (shift: constant <- "hello!")
mario@181:  * (reduce: simple_spec_init: simple_specification ASSIGN constant)
mario@181:  * (reduce: ...)
mario@181:  *
mario@181:  *
mario@181:  * Route 2:
mario@181:  * type_declaration: string_type_declaration
mario@181:  * string_type_declaration: identifier ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init
mario@181:  * (shift:  identifier <- 'new_str_type')
mario@181:  * elementary_string_type_name: STRING
mario@181:  * (shift: elementary_string_type_name <- STRING)
mario@181:  * (shift: string_type_declaration_size <-  empty )
mario@181:  * string_type_declaration_init: ASSIGN character_string
mario@181:  * (shift: character_string <- "hello!")
mario@181:  * (reduce: string_type_declaration_init <- ASSIGN character_string)
mario@181:  * (reduce: string_type_declaration <- identifier ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init )
mario@181:  * (reduce: type_declaration <- string_type_declaration)
mario@181:  *
mario@181:  *
mario@181:  * At first glance it seems that removing route 1 would make
mario@181:  * the most sense. Unfortunately the construct 'simple_spec_init'
mario@181:  * shows up multiple times in other rules, so changing this construct
mario@181:  * would also mean changing all the rules in which it appears.
mario@181:  * I (Mario) therefore chose to remove route 2 instead. This means
mario@181:  * that the above declaration gets stored in a
mario@181:  * simple_type_declaration_c, and not in a string_type_declaration_c
mario@181:  * as would be expected!
mario@181:  */
mario@181: /*  string_type_name ':' elementary_string_type_name string_type_declaration_size string_type_declaration_init */
mario@181: #if 0
mario@181: SYM_REF4(string_type_declaration_c,	string_type_name,
mario@181: 					elementary_string_type_name,
mario@181: 					string_type_declaration_size,
mario@181: 					string_type_declaration_init) /* may be == NULL! */
mario@181: #endif
msousa@432: void *type_initial_value_c::visit(string_type_declaration_c *symbol)	{
msousa@432:   return handle_type_spec(symbol->elementary_string_type_name, symbol->string_type_declaration_init);
msousa@432: }
mario@181: 
mario@181: 
mario@181: type_initial_value_c	*type_initial_value_c::_instance = NULL;
mario@181: real_c			*type_initial_value_c::real_0 = NULL;
mario@181: integer_c		*type_initial_value_c::integer_0 = NULL;
mario@181: integer_c		*type_initial_value_c::integer_1 = NULL;
mario@181: boolean_literal_c	*type_initial_value_c::bool_0 = NULL;
mario@181: date_literal_c	*type_initial_value_c::date_literal_0 = NULL;
mario@181: daytime_c	*type_initial_value_c::daytime_literal_0 = NULL;
mario@181: duration_c	*type_initial_value_c::time_0 = NULL;
mario@181: date_c	*type_initial_value_c::date_0 = NULL;
mario@181: time_of_day_c	*type_initial_value_c::tod_0 = NULL;
mario@181: date_and_time_c	*type_initial_value_c::dt_0 = NULL;
mario@181: single_byte_character_string_c *type_initial_value_c::string_0 = NULL;
mario@181: double_byte_character_string_c *type_initial_value_c::wstring_0 = NULL;