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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

/*

    27

 * 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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    34

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/*

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 *  Fill candidate list of data types for all symbols

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 */

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#include "fill_candidate_datatypes.hh"

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#include "datatype_functions.hh"

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#include <typeinfo>

    42

#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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    47

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

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static int debug = 0;

    49

    50

fill_candidate_datatypes_c::fill_candidate_datatypes_c(symbol_c *ignore) {

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}

    52

    53

fill_candidate_datatypes_c::~fill_candidate_datatypes_c(void) {

    54

}

    55

    56

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 */

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

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

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			return widen_table[k].result;

    62

	return NULL;

    63

}

    64

    65

    66

/* 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 (search_in_candidate_datatype_list(datatype, symbol->candidate_datatypes) >= 0) 

    70

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

    71

    return false;

    72

    73

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

    74

  symbol->candidate_datatypes.push_back(datatype);

    75

  return true;

    76

}

    77

    78

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    85

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

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

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/*

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

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

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

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 */

    93

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

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	symbol_c *call_param_value,  *param_datatype;

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	identifier_c *param_name;

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	function_param_iterator_c       fp_iterator(f_decl);

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	function_call_param_iterator_c fcp_iterator(f_call);

    98

	int extensible_parameter_highest_index = -1;

    99

	unsigned int i;

   100

   101

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

   102

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

   103

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

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

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		 */

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		do {

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			param_name = fp_iterator.next();

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

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			if(param_name == NULL) return false;

   110

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

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   112

		/* TODO: verify if it is lvalue when INOUT or OUTPUT parameters! */

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		/* Get the parameter type */

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		param_datatype = base_type(fp_iterator.param_type());

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   116

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

   117

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

   118

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

   119

	}

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	/* call is compatible! */

   121

	return true;

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}

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

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

   128

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

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	symbol_c *call_param_value, *call_param_name, *param_datatype;

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	symbol_c *verify_duplicate_param;

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	identifier_c *param_name;

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	function_param_iterator_c       fp_iterator(f_decl);

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	function_call_param_iterator_c fcp_iterator(f_call);

   134

	int extensible_parameter_highest_index = -1;

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	identifier_c *extensible_parameter_name;

   136

	unsigned int i;

   137

	bool is_first_param = true;

   138

   139

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

   140

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

   141

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

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		call_param_value = fcp_iterator.get_current_value();

   143

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

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		if (NULL == call_param_value) ERROR;

   145

   146

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

   147

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

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		/* Checking if there are duplicated parameter values */

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		verify_duplicate_param = fcp_iterator.search_f(call_param_name);

   151

		if(verify_duplicate_param != call_param_value)

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			return false;

   153

   154

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

   155

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

   156

   157

		/* Find the corresponding parameter in function declaration */

   158

		param_name = fp_iterator.search(call_param_name);

   159

		if(param_name == NULL) return false;

   160

		/* Get the parameter data type */

   161

		param_datatype = base_type(fp_iterator.param_type());

   162

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

   163

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

   164

   165

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

   166

		if          (function_call_param_iterator_c::assign_in  == call_param_dir) {

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

   168

			    (function_param_iterator_c::direction_inout != param_dir))

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				return false;

   170

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

   171

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

   172

				return false;

   173

		} else ERROR;

   174

   175

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

   176

		if (search_in_candidate_datatype_list(param_datatype, call_param_types) < 0)

   177

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

   178

   179

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

   180

		if (is_first_param)

   181

			if (NULL != first_param_datatype)

   182

				*first_param_datatype = param_datatype;

   183

		is_first_param = false;

   184

	}

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	/* call is compatible! */

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	return true;

   187

}

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   189

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   191

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/* Handle a generic function call!

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

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 * has already had all the candidate_datatype lists filled in!

   195

 *

   196

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

   197

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

   198

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

   199

 */

   200

/*

   201

typedef struct {

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  symbol_c *function_name,

   203

  symbol_c *nonformal_operand_list,

   204

  symbol_c *   formal_operand_list,

   205

   206

  std::vector <symbol_c *> &candidate_functions,  

   207

  symbol_c &*called_function_declaration,

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  int      &extensible_param_count

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} generic_function_call_t;

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*/

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/*

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

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

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                                                       std::vector <symbol_c *> *candidate_datatypes,

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

   216

  */

   217

void fill_candidate_datatypes_c::handle_function_call(symbol_c *fcall, generic_function_call_t fcall_data) {

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	function_declaration_c *f_decl;

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	list_c *parameter_list;

   220

	list_c *parameter_candidate_datatypes;

   221

	symbol_c *returned_parameter_type;

   222

   223

	if (debug) std::cout << "function()\n";

   224

   225

	function_symtable_t::iterator lower = function_symtable.lower_bound(fcall_data.function_name);

   226

	function_symtable_t::iterator upper = function_symtable.upper_bound(fcall_data.function_name);

   227

	/* If the name of the function being called is not found in the function symbol table, then this is an invalid call */

   228

	/* Since the lexical parser already checks for this, then if this occurs then we have an internal compiler error. */

   229

	if (lower == function_symtable.end()) ERROR;

   230

   231

	/* Look for all compatible function declarations, and add their return datatypes 

   232

	 * to the candidate_datatype list of this function invocation. 

   233

	 *

   234

	 * If only one function exists, we add its return datatype to the candidate_datatype list,

   235

	 * even if the parameters passed to it are invalid.

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	 * This guarantees that the remainder of the expression in which the function call is inserted

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	 * is treated as if the function call returns correctly, and therefore does not generate

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	 * spurious error messages.

   239

	 * Even if the parameters to the function call are invalid, doing this is still safe, as the 

   240

	 * expressions inside the function call will themselves have erros and will  guarantee that 

   241

	 * compilation is aborted in stage3 (in print_datatypes_error_c).

   242

	 */

   243

	if (function_symtable.multiplicity(fcall_data.function_name) == 1) {

   244

		f_decl = function_symtable.get_value(lower);

   245

		returned_parameter_type = base_type(f_decl->type_name);

   246

		if (add_datatype_to_candidate_list(fcall, returned_parameter_type))

   247

			/* we only add it to the function declaration list if this entry was not already present in the candidate datatype list! */

   248

			fcall_data.candidate_functions.push_back(f_decl);

   249

   250

	}

   251

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

   252

		bool compatible = false;

   253

   254

		f_decl = function_symtable.get_value(lower);

   255

		/* Check if function declaration in symbol_table is compatible with parameters */

   256

		if (NULL != fcall_data.nonformal_operand_list) compatible=match_nonformal_call(fcall, f_decl);

   257

		if (NULL != fcall_data.   formal_operand_list) compatible=   match_formal_call(fcall, f_decl);

   258

		if (compatible) {

   259

			/* Add the data type returned by the called functions. 

   260

			 * However, only do this if this data type is not already present in the candidate_datatypes list_c

   261

			 */

   262

			returned_parameter_type = base_type(f_decl->type_name);		

   263

			if (add_datatype_to_candidate_list(fcall, returned_parameter_type))

   264

				/* we only add it to the function declaration list if this entry was not already present in the candidate datatype list! */

   265

				fcall_data.candidate_functions.push_back(f_decl);

   266

		}

   267

	}

   268

	if (debug) std::cout << "end_function() [" << fcall->candidate_datatypes.size() << "] result.\n";

   269

	return;

   270

}

   271

   272

   273

/* handle implicit FB call in IL.

   274

 * e.g.  CLK ton_var

   275

 *        CU counter_var

   276

 */

   277

void fill_candidate_datatypes_c::handle_implicit_il_fb_call(symbol_c *il_instruction, const char *param_name, symbol_c *&called_fb_declaration) {

   278

	symbol_c *fb_type_id = search_varfb_instance_type->get_basetype_id(il_operand);

   279

  	/* Although a call to a non-declared FB is a semantic error, this is currently caught by stage 2! */

   280

	if (NULL == fb_type_id) ERROR;

   281

   282

	function_block_declaration_c *fb_decl = function_block_type_symtable.find_value(fb_type_id);

   283

	if (function_block_type_symtable.end_value() == fb_decl)

   284

		/* The il_operand is not the name of a FB instance. Most probably it is the name of a variable of some other type.

   285

		 * this is a semantic error.

   286

		 */

   287

		fb_decl = NULL;

   288

   289

	/* The narrow_candidate_datatypes_c does not rely on this called_fb_declaration pointer being == NULL to conclude that

   290

	 * we have a datatype incompatibility error, so we set it to fb_decl to allow the print_datatype_error_c to print out

   291

	 * more informative error messages!

   292

	 */

   293

	called_fb_declaration = fb_decl;

   294

   295

	/* This implicit FB call does not change the value stored in the current/default IL variable */

   296

	/* It does, however, require that the datatype be compatible with the input parameter of the FB being called. 

   297

	 * If we were to follow the filling & narrowing algorithm correctly (implemented in fill_candidate_datatypes_c

   298

	 * & narrow_candidate_datatypes_c respectively), we should be restricting the candidate_datatpes to the datatypes

   299

	 * that are compatible to the FB call. 

   300

	 * However, doing the above will often result in some very confusing error messages for the user, especially in the case

   301

	 * in which the FB call is wrong, so the resulting cadidate datatypes is an empty list. In this case, the user would see

   302

	 * many error messages related to the IL instructions that follow the FB call, even though those IL instructions may be perfectly

   303

	 * correct.

   304

	 * For now, we will simply let the narrow_candidate_datatypes_c verify if the datatypes are compatible (something that should be done

   305

	 * here).

   306

	 */

   307

	if (NULL != prev_il_instruction)

   308

		il_instruction->candidate_datatypes = prev_il_instruction->candidate_datatypes; 

   309

   310

	if (debug) std::cout << "handle_implicit_il_fb_call() [" << prev_il_instruction->candidate_datatypes.size() << "] ==> " << il_instruction->candidate_datatypes.size() << " result.\n";

   311

}

   312

   313

   314

/* a helper function... */

   315

symbol_c *fill_candidate_datatypes_c::base_type(symbol_c *symbol) {

   316

	/* NOTE: symbol == NULL is valid. It will occur when, for e.g., an undefined/undeclared symbolic_variable is used

   317

	 *       in the code.

   318

	 */

   319

	if (symbol == NULL) return NULL;

   320

	return (symbol_c *)symbol->accept(search_base_type);

   321

}

   322

   323

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

   324

/* B 1.2 - Constants */

   325

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

   326

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

   327

/* B 1.2.1 - Numeric Literals */

   328

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

   368

void *fill_candidate_datatypes_c::visit(real_c *symbol) {

   369

	int calc_size;

   370

   371

	calc_size = sizeoftype(symbol);

   372

	if (calc_size <= sizeoftype(&search_constant_type_c::real_type_name))

   374

	if (calc_size <= sizeoftype(&search_constant_type_c::lreal_type_name))

   376

	if (debug) std::cout << "ANY_REAL [" << symbol->candidate_datatypes.size() << "]" << std::endl;

   377

	return NULL;

   378

}

   379

   382

void *fill_candidate_datatypes_c::visit(integer_c *symbol) {

   390

	int calc_size;

   391

   392

	calc_size = sizeoftype(symbol);

   397

	if (debug) std::cout << "neg ANY_REAL [" << symbol->candidate_datatypes.size() << "]" << std::endl;

   398

	return NULL;

   399

}

   400

   402

void *fill_candidate_datatypes_c::visit(neg_integer_c *symbol) {

   403

	int calc_size;

   404

   405

	calc_size = sizeoftype(symbol);

   406

	if (calc_size <= sizeoftype(&search_constant_type_c::int_type_name))

   408

	if (calc_size <= sizeoftype(&search_constant_type_c::sint_type_name))

   410

	if (calc_size <= sizeoftype(&search_constant_type_c::dint_type_name))

   412

	if (calc_size <= sizeoftype(&search_constant_type_c::lint_type_name))

   414

	if (debug) std::cout << "neg ANY_INT [" << symbol->candidate_datatypes.size() << "]" << std::endl;

   415

	return NULL;

   416

}

   417

   419

void *fill_candidate_datatypes_c::visit(binary_integer_c *symbol) {

   421

	if (debug) std::cout << "ANY_INT [" << symbol->candidate_datatypes.size()<< "]" << std::endl;

   422

	return NULL;

   423

}

   424

   427

void *fill_candidate_datatypes_c::visit(octal_integer_c *symbol) {

   429

	if (debug) std::cout << "ANY_INT [" << symbol->candidate_datatypes.size()<< "]" << std::endl;

   430

	return NULL;

   431

}

   432

   435

void *fill_candidate_datatypes_c::visit(hex_integer_c *symbol) {

   437

	if (debug) std::cout << "ANY_INT [" << symbol->candidate_datatypes.size()<< "]" << std::endl;

   438

	return NULL;

   439

}

   440

   442

// SYM_REF2(integer_literal_c, type, value)

   450

void *fill_candidate_datatypes_c::visit(integer_literal_c *symbol) {

   451

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

   452

	if (search_in_candidate_datatype_list(symbol->type, symbol->value->candidate_datatypes) >= 0)

   453

		add_datatype_to_candidate_list(symbol, symbol->type);

   454

	if (debug) std::cout << "INT_LITERAL [" << symbol->candidate_datatypes.size() << "]\n";

   455

	return NULL;

   456

}

   457

   458

void *fill_candidate_datatypes_c::visit(real_literal_c *symbol) {

   459

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

   460

	if (search_in_candidate_datatype_list(symbol->type, symbol->value->candidate_datatypes) >= 0)

   461

		add_datatype_to_candidate_list(symbol, symbol->type);

   462

	if (debug) std::cout << "REAL_LITERAL [" << symbol->candidate_datatypes.size() << "]\n";

   463

	return NULL;

   464

}

   465

   466

void *fill_candidate_datatypes_c::visit(bit_string_literal_c *symbol) {

   467

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

   468

	if (search_in_candidate_datatype_list(symbol->type, symbol->value->candidate_datatypes) >= 0)

   469

		add_datatype_to_candidate_list(symbol, symbol->type);

   470

	return NULL;

   471

}

   472

   473

void *fill_candidate_datatypes_c::visit(boolean_literal_c *symbol) {

   474

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

   475

 	if (search_in_candidate_datatype_list(symbol->type, symbol->value->candidate_datatypes) >= 0)

   476

		/* if an explicit datat type has been provided (e.g. SAFEBOOL#true), check whether

   477

		 * the possible datatypes of the value is consistent with the desired type.

   478

		 */

   479

		add_datatype_to_candidate_list(symbol, symbol->type);

   480

	else {

   481

		/* Then only a literal TRUE or FALSE was given! */

   482

		/* In this case, symbol->type will be NULL!     */

   484

	}

   485

	return NULL;

   486

}

   487

   488

void *fill_candidate_datatypes_c::visit(boolean_true_c *symbol) {

   490

	return NULL;

   491

}

   492

   493

void *fill_candidate_datatypes_c::visit(boolean_false_c *symbol) {

   495

	return NULL;

   496

}

   497

   498

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

   499

/* B.1.2.2   Character Strings */

   500

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

   501