1 /*

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

     3  *

     4  *  Copyright (C) 2009-2012  Mario de Sousa (msousa@fe.up.pt)

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

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

     7  *

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

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

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

    11  *  (at your option) any later version.

    12  *

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

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

    15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    16  *  GNU General Public License for more details.

    17  *

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

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

    20  *

    21  *

    22  * This code is made available on the understanding that it will not be

    23  * used in safety-critical situations without a full and competent review.

    24  */

    25 

    26 /*

    27  * An IEC 61131-3 compiler.

    28  *

    29  * Based on the

    30  * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

    31  *

    32  */

    33 

    34 

    35 /*

    36  *  Narrow class select and store a data type from candidate data types list for all symbols

    37  */

    38 

    39 #include "narrow_candidate_datatypes.hh"

    40 #include "datatype_functions.hh"

    41 #include <typeinfo>

    42 #include <list>

    43 #include <string>

    44 #include <string.h>

    45 #include <strings.h>

    46 

    47 

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

    49 static int debug = 0;

    50 

    51 narrow_candidate_datatypes_c::narrow_candidate_datatypes_c(symbol_c *ignore) {

    52 }

    53 

    54 narrow_candidate_datatypes_c::~narrow_candidate_datatypes_c(void) {

    55 }

    56 

    57 bool narrow_candidate_datatypes_c::is_widening_compatible(symbol_c *left_type, symbol_c *right_type, symbol_c *result_type, const struct widen_entry widen_table[]) {

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

    59 		if        ((typeid(*left_type)   == typeid(*widen_table[k].left))

    60 		        && (typeid(*right_type)  == typeid(*widen_table[k].right))

    61 				&& (typeid(*result_type) == typeid(*widen_table[k].result))) {

    62 			return true;

    63 		}

    64 	}

    65 	return false;

    66 }

    67 

    68 void narrow_candidate_datatypes_c::narrow_nonformal_call(symbol_c *f_call, symbol_c *f_decl) {

    69 	symbol_c *call_param_value,  *param_type;

    70 	identifier_c *param_name;

    71 	function_param_iterator_c       fp_iterator(f_decl);

    72 	function_call_param_iterator_c fcp_iterator(f_call);

    73 	int extensible_parameter_highest_index = -1;

    74 	identifier_c *extensible_parameter_name;

    75 	unsigned int i;

    76 

    77 

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

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

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

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

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

    83 		 */

    84 		do {

    85 			param_name = fp_iterator.next();

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

    87 			if(param_name == NULL) {

    88 				return;

    89 			}

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

    91 

    92 		/* Get the parameter type */

    93 		call_param_value->datatype = base_type(fp_iterator.param_type());

    94 		call_param_value->accept(*this);

    95 		if (extensible_parameter_highest_index < fp_iterator.extensible_param_index()) {

    96 			extensible_parameter_highest_index = fp_iterator.extensible_param_index();

    97 			extensible_parameter_name = param_name;

    98 		}

    99 	}

   100     int extensible_param_count = -1;

   101     if (extensible_parameter_highest_index >=0) /* if call to extensible function */

   102       extensible_param_count = 1 + extensible_parameter_highest_index - fp_iterator.first_extensible_param_index();

   103     function_invocation_c  *function_invocation  = dynamic_cast<function_invocation_c  *>(f_call);

   104     if (function_invocation  != NULL) function_invocation->extensible_param_count = extensible_param_count;

   105 

   106 }

   107 

   108 void narrow_candidate_datatypes_c::narrow_formal_call(symbol_c *f_call, symbol_c *f_decl) {

   109 	symbol_c *call_param_value, *call_param_name, *param_type;

   110 	symbol_c *verify_duplicate_param;

   111 	identifier_c *param_name;

   112 	function_param_iterator_c       fp_iterator(f_decl);

   113 	function_call_param_iterator_c fcp_iterator(f_call);

   114 	int extensible_parameter_highest_index = -1;

   115 	identifier_c *extensible_parameter_name;

   116 	unsigned int i;

   117 

   118 

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

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

   121 

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

   123 		call_param_value = fcp_iterator.get_current_value();

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

   125 		if (NULL == call_param_value) ERROR;

   126 

   127 		/* Find the corresponding parameter in function declaration */

   128 		param_name = fp_iterator.search(call_param_name);

   129 

   130 		/* Get the parameter type */

   131 		call_param_name->datatype = base_type(fp_iterator.param_type());

   132 		call_param_name->accept(*this);

   133 	    /* the first parameter (il_def_variable) is correct */

   134 	    if (extensible_parameter_highest_index < fp_iterator.extensible_param_index()) {

   135 	      extensible_parameter_highest_index = fp_iterator.extensible_param_index();

   136 	    }

   137 	}

   138 	/* The function call may not have any errors! */

   139 	/* In the case of a call to an extensible function, we store the highest index

   140 	 * of the extensible parameters this particular call uses, in the symbol_c object

   141 	 * of the function call itself!

   142 	 * In calls to non-extensible functions, this value will be set to -1.

   143 	 * This information is later used in stage4 to correctly generate the

   144 	 * output code.

   145 	 */

   146 	int extensible_param_count = -1;

   147 	if (extensible_parameter_highest_index >=0) /* if call to extensible function */

   148 		extensible_param_count = 1 + extensible_parameter_highest_index - fp_iterator.first_extensible_param_index();

   149 	function_invocation_c  *function_invocation  = dynamic_cast<function_invocation_c  *>(f_call);

   150 	if (function_invocation  != NULL) function_invocation->extensible_param_count = extensible_param_count;

   151 }

   152 

   153 /* a helper function... */

   154 symbol_c *narrow_candidate_datatypes_c::base_type(symbol_c *symbol) {

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

   156 	 *       in the code.

   157 	 */

   158 	return NULL;

   159 }

   160 

   161 /*********************/

   162 /* B 1.2 - Constants */

   163 /*********************/

   164 

   165 /**********************/

   166 /* B 1.3 - Data types */

   167 /**********************/

   168 /********************************/

   169 /* B 1.3.3 - Derived data types */

   170 /********************************/

   171 /*  signed_integer DOTDOT signed_integer */

   172 // SYM_REF2(subrange_c, lower_limit, upper_limit)

   173 void *narrow_candidate_datatypes_c::visit(subrange_c *symbol) {

   174 	symbol->lower_limit->datatype = symbol->datatype;

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

   176 	symbol->upper_limit->datatype = symbol->datatype;

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

   178 	return NULL;

   179 }

   180 

   181 

   182 /*********************/

   183 /* B 1.4 - Variables */

   184 /*********************/

   185 

   186 /********************************************/

   187 /* B 1.4.1 - Directly Represented Variables */

   188 /********************************************/

   189 

   190 /*************************************/

   191 /* B 1.4.2 - Multi-element variables */

   192 /*************************************/

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

   194 // SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

   195 void *narrow_candidate_datatypes_c::visit(array_variable_c *symbol) {

   196 	/* we need to check the data types of the expressions used for the subscripts... */

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

   198 	return NULL;

   199 }

   200 

   201 

   202 /* subscript_list ',' subscript */

   203 // SYM_LIST(subscript_list_c)

   204 void *narrow_candidate_datatypes_c::visit(subscript_list_c *symbol) {

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

   206 		for (unsigned int k = 0; k < symbol->elements[i]->candidate_datatypes.size(); k++) {

   207 			if (is_ANY_INT_type(symbol->elements[i]->candidate_datatypes[k]))

   208 				symbol->elements[i]->datatype = symbol->elements[i]->candidate_datatypes[k];

   209 		}

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

   211 	}

   212 	return NULL;  

   213 }

   214 

   215 

   216 

   217 /************************************/

   218 /* B 1.5 Program organization units */

   219 /************************************/

   220 /*********************/

   221 /* B 1.5.1 Functions */

   222 /*********************/

   223 void *narrow_candidate_datatypes_c::visit(function_declaration_c *symbol) {

   224 	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   225 	if (debug) printf("Narrowing candidate data types list in body of function %s\n", ((token_c *)(symbol->derived_function_name))->value);

   226 	prev_il_instruction = NULL;

   227 	symbol->function_body->accept(*this);

   228 	prev_il_instruction = NULL;

   229 	delete search_varfb_instance_type;

   230 	search_varfb_instance_type = NULL;

   231 	return NULL;

   232 }

   233 

   234 /***************************/

   235 /* B 1.5.2 Function blocks */

   236 /***************************/

   237 void *narrow_candidate_datatypes_c::visit(function_block_declaration_c *symbol) {

   238 	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   239 	if (debug) printf("Narrowing candidate data types list in body of FB %s\n", ((token_c *)(symbol->fblock_name))->value);

   240 	prev_il_instruction = NULL;

   241 	symbol->fblock_body->accept(*this);

   242 	prev_il_instruction = NULL;

   243 	delete search_varfb_instance_type;

   244 	search_varfb_instance_type = NULL;

   245 	return NULL;

   246 }

   247 

   248 /********************/

   249 /* B 1.5.3 Programs */

   250 /********************/

   251 void *narrow_candidate_datatypes_c::visit(program_declaration_c *symbol) {

   252 	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   253 	if (debug) printf("Narrowing candidate data types list in body of program %s\n", ((token_c *)(symbol->program_type_name))->value);

   254 	prev_il_instruction = NULL;

   255 	symbol->function_block_body->accept(*this);

   256 	prev_il_instruction = NULL;

   257 	delete search_varfb_instance_type;

   258 	search_varfb_instance_type = NULL;

   259 	return NULL;

   260 }

   261 

   262 

   263 /********************************/

   264 /* B 1.7 Configuration elements */

   265 /********************************/

   266 void *narrow_candidate_datatypes_c::visit(configuration_declaration_c *symbol) {

   267 #if 0

   268 	// TODO !!!

   269 	/* for the moment we must return NULL so semantic analysis of remaining code is not interrupted! */

   270 #endif

   271 	return NULL;

   272 }

   273 

   274 

   275 /****************************************/

   276 /* B.2 - Language IL (Instruction List) */

   277 /****************************************/

   278 /***********************************/

   279 /* B 2.1 Instructions and Operands */

   280 /***********************************/

   281 // void *visit(instruction_list_c *symbol);

   282 void *narrow_candidate_datatypes_c::visit(il_simple_operation_c *symbol) {

   283 	il_operand = symbol->il_operand;

   284 	if (NULL != symbol->il_operand) {

   285 		symbol->il_operand->accept(*this);

   286 	}

   287 	/* recursive call to see whether data types are compatible */

   288 	symbol->il_simple_operator->accept(*this);

   289 	il_operand = NULL;

   290 	return NULL;

   291 }

   292 

   293 void *narrow_candidate_datatypes_c::visit(il_function_call_c *symbol) {

   294 	return NULL;

   295 }

   296 

   297 /* MJS: Manuele, could you please not delete the following 2 lines of comments. They help me understand where this class is used

   298  *     and when it is created by bison - syntax parse, and how it can show up in the abstract syntax tree.

   299  *

   300  *       Actually, it could be helpful if we could have all the similar comments already present in visit_expression_type_c

   301  *       in the 3 new classes fill/narrow/print candidate datatype 

   302  */

   303 /* | il_expr_operator '(' [il_operand] eol_list [simple_instr_list] ')' */

   304 // SYM_REF3(il_expression_c, il_expr_operator, il_operand, simple_instr_list);

   305 void *narrow_candidate_datatypes_c::visit(il_expression_c *symbol) {

   306 /* MJS: TODO... */

   307 return NULL;

   308 }

   309 

   310 void *narrow_candidate_datatypes_c::visit(il_fb_call_c *symbol) {

   311 	return NULL;

   312 }

   313 

   314 void *narrow_candidate_datatypes_c::visit(il_formal_funct_call_c *symbol) {

   315 	return NULL;

   316 }

   317 

   318 

   319 /*

   320     void *visit(il_operand_list_c *symbol);

   321     void *visit(simple_instr_list_c *symbol);

   322     void *visit(il_param_list_c *symbol);

   323     void *visit(il_param_assignment_c *symbol);

   324     void *visit(il_param_out_assignment_c *symbol);

   325  */

   326 

   327 /*******************/

   328 /* B 2.2 Operators */

   329 /*******************/

   330 void *narrow_candidate_datatypes_c::visit(LD_operator_c *symbol) {

   331 	prev_il_instruction = symbol;

   332 	return NULL;

   333 }

   334 

   335 void *narrow_candidate_datatypes_c::visit(LDN_operator_c *symbol) {

   336 	if (symbol->candidate_datatypes.size() != 1)

   337 		return NULL;

   338 	symbol->datatype = symbol->candidate_datatypes[0];

   339 	il_operand->datatype = symbol->datatype;

   340 	il_operand->accept(*this);

   341 	prev_il_instruction = symbol;

   342 	return NULL;

   343 }

   344 

   345 void *narrow_candidate_datatypes_c::visit(ST_operator_c *symbol) {

   346 	if (symbol->candidate_datatypes.size() != 1)

   347 		return NULL;

   348 	symbol->datatype = symbol->candidate_datatypes[0];

   349 	il_operand->datatype = symbol->datatype;

   350 	il_operand->accept(*this);

   351 	prev_il_instruction = symbol;

   352 	return NULL;

   353 }

   354 

   355 void *narrow_candidate_datatypes_c::visit(STN_operator_c *symbol) {

   356 	if (symbol->candidate_datatypes.size() != 1)

   357 		return NULL;

   358 	symbol->datatype = symbol->candidate_datatypes[0];

   359 	il_operand->datatype = symbol->datatype;

   360 	il_operand->accept(*this);

   361 	prev_il_instruction = symbol;

   362 	return NULL;

   363 }

   364 

   365 void *narrow_candidate_datatypes_c::visit(NOT_operator_c *symbol) {

   366 	prev_il_instruction = symbol;

   367 	return NULL;

   368 }

   369 

   370 void *narrow_candidate_datatypes_c::visit(S_operator_c *symbol) {

   371 	if (symbol->candidate_datatypes.size() != 1)

   372 		return NULL;

   373 	symbol->datatype = symbol->candidate_datatypes[0];

   374 	il_operand->datatype = symbol->datatype;

   375 	il_operand->accept(*this);

   376 	prev_il_instruction = symbol;

   377 	return NULL;

   378 }

   379 

   380 void *narrow_candidate_datatypes_c::visit(R_operator_c *symbol) {

   381 	if (symbol->candidate_datatypes.size() != 1)

   382 		return NULL;

   383 	symbol->datatype = symbol->candidate_datatypes[0];

   384 	il_operand->datatype = symbol->datatype;

   385 	il_operand->accept(*this);

   386 	prev_il_instruction = symbol;

   387 	return NULL;

   388 }

   389 

   390 void *narrow_candidate_datatypes_c::visit(S1_operator_c *symbol) {

   391 	if (symbol->candidate_datatypes.size() != 1)

   392 		return NULL;

   393 	symbol->datatype = symbol->candidate_datatypes[0];

   394 	il_operand->datatype = symbol->datatype;

   395 	il_operand->accept(*this);

   396 	prev_il_instruction = symbol;

   397 	return NULL;

   398 }

   399 

   400 void *narrow_candidate_datatypes_c::visit(R1_operator_c *symbol) {

   401 	if (symbol->candidate_datatypes.size() != 1)

   402 		return NULL;

   403 	symbol->datatype = symbol->candidate_datatypes[0];

   404 	il_operand->datatype = symbol->datatype;

   405 	il_operand->accept(*this);

   406 	prev_il_instruction = symbol;

   407 	return NULL;

   408 }

   409 

   410 void *narrow_candidate_datatypes_c::visit(CLK_operator_c *symbol) {

   411 	prev_il_instruction = symbol;

   412 	return NULL;

   413 }

   414 

   415 void *narrow_candidate_datatypes_c::visit(CU_operator_c *symbol) {

   416 	prev_il_instruction = symbol;

   417 	return NULL;

   418 }

   419 

   420 void *narrow_candidate_datatypes_c::visit(CD_operator_c *symbol) {

   421 	prev_il_instruction = symbol;

   422 	return NULL;

   423 }

   424 

   425 void *narrow_candidate_datatypes_c::visit(PV_operator_c *symbol) {

   426 	prev_il_instruction = symbol;

   427 	return NULL;

   428 }

   429 

   430 void *narrow_candidate_datatypes_c::visit(IN_operator_c *symbol) {

   431 	prev_il_instruction = symbol;

   432 	return NULL;

   433 }

   434 

   435 void *narrow_candidate_datatypes_c::visit(PT_operator_c *symbol) {

   436 	prev_il_instruction = symbol;

   437 	return NULL;

   438 }

   439 

   440 void *narrow_candidate_datatypes_c::visit(AND_operator_c *symbol) {

   441 	if (symbol->candidate_datatypes.size() != 1)

   442 		return NULL;

   443 	symbol->datatype = symbol->candidate_datatypes[0];

   444 	il_operand->datatype = symbol->datatype;

   445 	il_operand->accept(*this);

   446 	prev_il_instruction = symbol;

   447 	return NULL;

   448 }

   449 

   450 void *narrow_candidate_datatypes_c::visit(OR_operator_c *symbol) {

   451 	if (symbol->candidate_datatypes.size() != 1)

   452 		return NULL;

   453 	symbol->datatype = symbol->candidate_datatypes[0];

   454 	il_operand->datatype = symbol->datatype;

   455 	il_operand->accept(*this);

   456 	prev_il_instruction = symbol;

   457 	return NULL;

   458 }

   459 

   460 void *narrow_candidate_datatypes_c::visit(XOR_operator_c *symbol) {

   461 	if (symbol->candidate_datatypes.size() != 1)

   462 		return NULL;

   463 	symbol->datatype = symbol->candidate_datatypes[0];

   464 	il_operand->datatype = symbol->datatype;

   465 	il_operand->accept(*this);

   466 	prev_il_instruction = symbol;

   467 	return NULL;

   468 }

   469 

   470 void *narrow_candidate_datatypes_c::visit(ANDN_operator_c *symbol) {

   471 	if (symbol->candidate_datatypes.size() != 1)

   472 		return NULL;

   473 	symbol->datatype = symbol->candidate_datatypes[0];

   474 	il_operand->datatype = symbol->datatype;

   475 	il_operand->accept(*this);

   476 	prev_il_instruction = symbol;

   477 	return NULL;

   478 }

   479 

   480 void *narrow_candidate_datatypes_c::visit(ORN_operator_c *symbol) {

   481 	if (symbol->candidate_datatypes.size() != 1)

   482 		return NULL;

   483 	symbol->datatype = symbol->candidate_datatypes[0];

   484 	il_operand->datatype = symbol->datatype;

   485 	il_operand->accept(*this);

   486 	prev_il_instruction = symbol;

   487 	return NULL;

   488 }

   489 

   490 void *narrow_candidate_datatypes_c::visit(XORN_operator_c *symbol) {

   491 	if (symbol->candidate_datatypes.size() != 1)

   492 		return NULL;

   493 	symbol->datatype = symbol->candidate_datatypes[0];

   494 	il_operand->datatype = symbol->datatype;

   495 	il_operand->accept(*this);

   496 	prev_il_instruction = symbol;

   497 	return NULL;

   498 }

   499 

   500 void *narrow_candidate_datatypes_c::visit(ADD_operator_c *symbol) {

   501 	prev_il_instruction = symbol;

   502 	return NULL;

   503 }

   504 

   505 void *narrow_candidate_datatypes_c::visit(SUB_operator_c *symbol) {

   506 	prev_il_instruction = symbol;

   507 	return NULL;

   508 }

   509 

   510 void *narrow_candidate_datatypes_c::visit(MUL_operator_c *symbol) {

   511 	prev_il_instruction = symbol;

   512 	return NULL;

   513 }

   514 

   515 void *narrow_candidate_datatypes_c::visit(DIV_operator_c *symbol) {

   516 	prev_il_instruction = symbol;

   517 	return NULL;

   518 }

   519 

   520 void *narrow_candidate_datatypes_c::visit(MOD_operator_c *symbol) {

   521 	prev_il_instruction = symbol;

   522 	return NULL;

   523 }

   524 

   525 void *narrow_candidate_datatypes_c::visit(GT_operator_c *symbol) {

   526 	prev_il_instruction = symbol;

   527 	return NULL;

   528 }

   529 

   530 void *narrow_candidate_datatypes_c::visit(GE_operator_c *symbol) {

   531 	prev_il_instruction = symbol;

   532 	return NULL;

   533 }

   534 

   535 void *narrow_candidate_datatypes_c::visit(EQ_operator_c *symbol) {

   536 	prev_il_instruction = symbol;

   537 	return NULL;

   538 }

   539 

   540 void *narrow_candidate_datatypes_c::visit(LT_operator_c *symbol) {

   541 	prev_il_instruction = symbol;

   542 	return NULL;

   543 }

   544 

   545 void *narrow_candidate_datatypes_c::visit(LE_operator_c *symbol) {

   546 	prev_il_instruction = symbol;

   547 	return NULL;

   548 }

   549 

   550 void *narrow_candidate_datatypes_c::visit(NE_operator_c *symbol) {

   551 	prev_il_instruction = symbol;

   552 	return NULL;

   553 }

   554 

   555 void *narrow_candidate_datatypes_c::visit(CAL_operator_c *symbol) {

   556 	prev_il_instruction = symbol;

   557 	return NULL;

   558 }

   559 

   560 void *narrow_candidate_datatypes_c::visit(CALC_operator_c *symbol) {

   561 	prev_il_instruction = symbol;

   562 	return NULL;

   563 }

   564 

   565 void *narrow_candidate_datatypes_c::visit(CALCN_operator_c *symbol) {

   566 	prev_il_instruction = symbol;

   567 	return NULL;

   568 }

   569 

   570 void *narrow_candidate_datatypes_c::visit(RET_operator_c *symbol) {

   571 	prev_il_instruction = symbol;

   572 	return NULL;

   573 }

   574 

   575 void *narrow_candidate_datatypes_c::visit(RETC_operator_c *symbol) {

   576 	prev_il_instruction = symbol;

   577 	return NULL;

   578 }

   579 

   580 void *narrow_candidate_datatypes_c::visit(RETCN_operator_c *symbol) {

   581 	prev_il_instruction = symbol;

   582 	return NULL;

   583 }

   584 

   585 void *narrow_candidate_datatypes_c::visit(JMP_operator_c *symbol) {

   586 	prev_il_instruction = symbol;

   587 	return NULL;

   588 }

   589 

   590 void *narrow_candidate_datatypes_c::visit(JMPC_operator_c *symbol) {

   591 	prev_il_instruction = symbol;

   592 	return NULL;

   593 }

   594 

   595 void *narrow_candidate_datatypes_c::visit(JMPCN_operator_c *symbol) {

   596 	prev_il_instruction = symbol;

   597 	return NULL;

   598 }

   599 

   600 /* Symbol class handled together with function call checks */

   601 // void *visit(il_assign_operator_c *symbol, variable_name);

   602 /* Symbol class handled together with function call checks */

   603 // void *visit(il_assign_operator_c *symbol, option, variable_name);

   604 

   605 

   606 /***************************************/

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

   608 /***************************************/

   609 /***********************/

   610 /* B 3.1 - Expressions */

   611 /***********************/

   612 

   613 void *narrow_candidate_datatypes_c::visit(or_expression_c *symbol) {

   614 	symbol_c * selected_type = NULL;

   615 	for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   616 		for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   617 			if (is_type_equal(symbol->l_exp->candidate_datatypes[i], symbol->r_exp->candidate_datatypes[j])) {

   618 				selected_type = symbol->l_exp->candidate_datatypes[i];

   619 				break;

   620 			}

   621 		}

   622 	}

   623 

   624 	if (NULL != selected_type) {

   625 		symbol->l_exp->datatype = selected_type;

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

   627 		symbol->r_exp->datatype = selected_type;

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

   629 	}

   630 	else

   631 		ERROR;

   632 	return NULL;

   633 }

   634 

   635 

   636 void *narrow_candidate_datatypes_c::visit(xor_expression_c *symbol) {

   637 	symbol_c * selected_type = NULL;

   638 	for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   639 		for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   640 			if (is_type_equal(symbol->l_exp->candidate_datatypes[i], symbol->r_exp->candidate_datatypes[j])) {

   641 				selected_type = symbol->l_exp->candidate_datatypes[i];

   642 				break;

   643 			}

   644 		}

   645 	}

   646 

   647 	if (NULL != selected_type) {

   648 		symbol->l_exp->datatype = selected_type;

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

   650 		symbol->r_exp->datatype = selected_type;

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

   652 	}

   653 	else

   654 		ERROR;

   655 	return NULL;

   656 }

   657 

   658 

   659 void *narrow_candidate_datatypes_c::visit(and_expression_c *symbol) {

   660 	symbol_c * selected_type = NULL;

   661 	for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   662 		for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   663 			if (typeid(*symbol->l_exp->candidate_datatypes[i]) == typeid(*symbol->r_exp->candidate_datatypes[j])) {

   664 				selected_type = symbol->l_exp->candidate_datatypes[i];

   665 				break;

   666 			}

   667 		}

   668 	}

   669 

   670 	if (NULL != selected_type) {

   671 		symbol->l_exp->datatype = selected_type;

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

   673 		symbol->r_exp->datatype = selected_type;

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

   675 	}

   676 	else

   677 		ERROR;

   678 	return NULL;

   679 }

   680 

   681 

   682 void *narrow_candidate_datatypes_c::visit(equ_expression_c *symbol) {

   683 	/* Here symbol->datatype has already assigned to BOOL

   684 	 * In conditional symbols like =, <>, =<, <, >, >= we have to set

   685 	 * l_exp and r_exp expression matched with compatible type.

   686 	 * Example:

   687 	 * 		INT#14 = INT#81

   688 	 * 		equ_expression_c symbol->datatype = BOOL from top visit

   689 	 * 		symbol->l_exp->datatype => INT

   690 	 * 		symbol->r_exp->datatype => INT

   691 	 */

   692 	symbol_c * selected_type = NULL;

   693 	for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   694 		for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   695 			if (typeid(*symbol->l_exp->candidate_datatypes[i]) == typeid(*symbol->r_exp->candidate_datatypes[j])) {

   696 				/*

   697 				 * We do not need to check whether the type is an ANY_ELEMENTARY here.

   698 				 * That was already done in fill_candidate_datatypes_c.

   699 				 */

   700 				selected_type = symbol->l_exp->candidate_datatypes[i];

   701 				break;

   702 			}

   703 		}

   704 	}

   705 

   706 	if (NULL != selected_type) {

   707 		symbol->l_exp->datatype = selected_type;

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

   709 		symbol->r_exp->datatype = selected_type;

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

   711 	}

   712 	else

   713 		ERROR;

   714 	return NULL;

   715 }

   716 

   717 void *narrow_candidate_datatypes_c::visit(notequ_expression_c *symbol)  {

   718 	symbol_c * selected_type = NULL;

   719 	for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   720 		for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   721 			if (typeid(*symbol->l_exp->candidate_datatypes[i]) == typeid(*symbol->r_exp->candidate_datatypes[j])) {

   722 				selected_type = symbol->l_exp->candidate_datatypes[i];

   723 				break;

   724 			}

   725 		}

   726 	}

   727 

   728 	if (NULL != selected_type) {

   729 		symbol->l_exp->datatype = selected_type;

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

   731 		symbol->r_exp->datatype = selected_type;

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

   733 	}

   734 	else

   735 		ERROR;

   736 	return NULL;

   737 }

   738 

   739 

   740 void *narrow_candidate_datatypes_c::visit(lt_expression_c *symbol) {

   741 	symbol_c * selected_type = NULL;

   742 	for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   743 		for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   744 			if (typeid(*symbol->l_exp->candidate_datatypes[i]) == typeid(*symbol->r_exp->candidate_datatypes[j])

   745 					&& is_ANY_ELEMENTARY_type(symbol->l_exp->candidate_datatypes[i])) {

   746 				selected_type = symbol->l_exp->candidate_datatypes[i];

   747 				break;

   748 			}

   749 		}

   750 	}

   751 

   752 	if (NULL != selected_type) {

   753 		symbol->l_exp->datatype = selected_type;

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

   755 		symbol->r_exp->datatype = selected_type;

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

   757 	}

   758 	else

   759 		ERROR;

   760 	return NULL;

   761 }

   762 

   763 

   764 void *narrow_candidate_datatypes_c::visit(gt_expression_c *symbol) {

   765 	symbol_c * selected_type = NULL;

   766 	for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   767 		for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   768 			if (typeid(*symbol->l_exp->candidate_datatypes[i]) == typeid(*symbol->r_exp->candidate_datatypes[j])

   769 					&& is_ANY_ELEMENTARY_type(symbol->l_exp->candidate_datatypes[i])) {

   770 				selected_type = symbol->l_exp->candidate_datatypes[i];

   771 				break;

   772 			}

   773 		}

   774 	}

   775 

   776 	if (NULL != selected_type) {

   777 		symbol->l_exp->datatype = selected_type;

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

   779 		symbol->r_exp->datatype = selected_type;

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

   781 	}

   782 	else

   783 		ERROR;

   784 	return NULL;

   785 }

   786 

   787 

   788 void *narrow_candidate_datatypes_c::visit(le_expression_c *symbol) {

   789 	symbol_c * selected_type = NULL;

   790 	for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   791 		for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   792 			if (typeid(*symbol->l_exp->candidate_datatypes[i]) == typeid(*symbol->r_exp->candidate_datatypes[j])

   793 					&& is_ANY_ELEMENTARY_type(symbol->l_exp->candidate_datatypes[i])) {

   794 				selected_type = symbol->l_exp->candidate_datatypes[i];

   795 				break;

   796 			}

   797 		}

   798 	}

   799 

   800 	if (NULL != selected_type) {

   801 		symbol->l_exp->datatype = selected_type;

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

   803 		symbol->r_exp->datatype = selected_type;

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

   805 	}

   806 	else

   807 		ERROR;

   808 	return NULL;

   809 }

   810 

   811 

   812 void *narrow_candidate_datatypes_c::visit(ge_expression_c *symbol) {

   813 	symbol_c * selected_type = NULL;

   814 	for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   815 		for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   816 			if (typeid(*symbol->l_exp->candidate_datatypes[i]) == typeid(*symbol->r_exp->candidate_datatypes[j])

   817 					&& is_ANY_ELEMENTARY_type(symbol->l_exp->candidate_datatypes[i])) {

   818 				selected_type = symbol->l_exp->candidate_datatypes[i];

   819 				break;

   820 			}

   821 		}

   822 	}

   823 

   824 	if (NULL != selected_type) {

   825 		symbol->l_exp->datatype = selected_type;

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

   827 		symbol->r_exp->datatype = selected_type;

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

   829 	}

   830 	else

   831 		ERROR;

   832 	return NULL;

   833 }

   834 

   835 void *narrow_candidate_datatypes_c::visit(add_expression_c *symbol) {

   836 	int count = 0;

   837 

   838 	if (is_ANY_NUM_compatible(symbol->datatype)) {

   839 		symbol->l_exp->datatype = symbol->datatype;

   840 		symbol->r_exp->datatype = symbol->datatype;

   841 		count++;

   842 	} else {

   843 		/* TIME data type */

   844 		for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   845 			for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   846 				/* test widening compatibility */

   847 				if (is_widening_compatible(symbol->l_exp->candidate_datatypes[i],

   848 						symbol->r_exp->candidate_datatypes[j],

   849 						symbol->datatype, widen_ADD_table)) {

   850 					symbol->l_exp->datatype = symbol->l_exp->candidate_datatypes[i];

   851 					symbol->r_exp->datatype = symbol->r_exp->candidate_datatypes[j];

   852 					count ++;

   853 				}

   854 			}

   855 		}

   856 	}

   857 	if (count > 1)

   858 		ERROR;

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

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

   861 	return NULL;

   862 }

   863 

   864 

   865 

   866 void *narrow_candidate_datatypes_c::visit(sub_expression_c *symbol) {

   867 	int count = 0;

   868 

   869 	if (is_ANY_NUM_compatible(symbol->datatype)) {

   870 		symbol->l_exp->datatype = symbol->datatype;

   871 		symbol->r_exp->datatype = symbol->datatype;

   872 		count++;

   873 	} else {

   874 		/* TIME data type */

   875 		for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   876 			for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   877 				/* test widening compatibility */

   878 				if (is_widening_compatible(symbol->l_exp->candidate_datatypes[i],

   879 						symbol->r_exp->candidate_datatypes[j],

   880 						symbol->datatype, widen_SUB_table)) {

   881 					symbol->l_exp->datatype = symbol->l_exp->candidate_datatypes[i];

   882 					symbol->r_exp->datatype = symbol->r_exp->candidate_datatypes[j];

   883 					count ++;

   884 				}

   885 			}

   886 		}

   887 	}

   888 	if (count > 1)

   889 		ERROR;

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

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

   892 	return NULL;

   893 }

   894 

   895 void *narrow_candidate_datatypes_c::visit(mul_expression_c *symbol) {

   896 	int count = 0;

   897 

   898 	if (is_ANY_NUM_compatible(symbol->datatype)) {

   899 		symbol->l_exp->datatype = symbol->datatype;

   900 		symbol->r_exp->datatype = symbol->datatype;

   901 		count++;

   902 	} else {

   903 		/* TIME data type */

   904 		for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   905 			for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   906 				/* test widening compatibility */

   907 				if (is_widening_compatible(symbol->l_exp->candidate_datatypes[i],

   908 						symbol->r_exp->candidate_datatypes[j],

   909 						symbol->datatype, widen_MUL_table)) {

   910 					symbol->l_exp->datatype = symbol->l_exp->candidate_datatypes[i];

   911 					symbol->r_exp->datatype = symbol->r_exp->candidate_datatypes[j];

   912 					count ++;

   913 				}

   914 			}

   915 		}

   916 	}

   917 	if (count > 1)

   918 		ERROR;

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

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

   921 	return NULL;

   922 }

   923 

   924 void *narrow_candidate_datatypes_c::visit(div_expression_c *symbol) {

   925 	int count = 0;

   926 

   927 	if (is_ANY_NUM_compatible(symbol->datatype)) {

   928 		symbol->l_exp->datatype = symbol->datatype;

   929 		symbol->r_exp->datatype = symbol->datatype;

   930 		count++;

   931 	} else {

   932 		/* TIME data type */

   933 		for(unsigned int i = 0; i < symbol->l_exp->candidate_datatypes.size(); i++) {

   934 			for(unsigned int j = 0; j < symbol->r_exp->candidate_datatypes.size(); j++) {

   935 				/* test widening compatibility */

   936 				if (is_widening_compatible(symbol->l_exp->candidate_datatypes[i],

   937 						symbol->r_exp->candidate_datatypes[j],

   938 						symbol->datatype, widen_DIV_table)) {

   939 					symbol->l_exp->datatype = symbol->l_exp->candidate_datatypes[i];

   940 					symbol->r_exp->datatype = symbol->r_exp->candidate_datatypes[j];

   941 					count ++;

   942 				}

   943 			}

   944 		}

   945 	}

   946 	if (count > 1)

   947 		ERROR;

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

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

   950 	return NULL;

   951 }

   952 

   953 

   954 void *narrow_candidate_datatypes_c::visit(mod_expression_c *symbol) {

   955 	symbol->l_exp->datatype = symbol->datatype;

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

   957 	symbol->r_exp->datatype = symbol->datatype;

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

   959 	return NULL;

   960 }

   961 

   962 

   963 void *narrow_candidate_datatypes_c::visit(power_expression_c *symbol) {

   964 	symbol->l_exp->datatype = symbol->datatype;

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

   966 	if (! symbol->r_exp->candidate_datatypes.size()){

   967 		symbol->r_exp->datatype = symbol->r_exp->candidate_datatypes[0];

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

   969 	}

   970 	return NULL;

   971 }

   972 

   973 

   974 void *narrow_candidate_datatypes_c::visit(neg_expression_c *symbol) {

   975 	symbol->exp->datatype = symbol->datatype;

   976 	symbol->exp->accept(*this);

   977 	return NULL;

   978 }

   979 

   980 

   981 void *narrow_candidate_datatypes_c::visit(not_expression_c *symbol) {

   982 	symbol->exp->datatype = symbol->datatype;

   983 	symbol->exp->accept(*this);

   984 	return NULL;

   985 }

   986 

   987 

   988 void *narrow_candidate_datatypes_c::visit(function_invocation_c *symbol) {

   989 	function_declaration_c *f_decl;

   990 	list_c *parameter_list;

   991 	list_c *parameter_candidate_datatypes;

   992 	function_symtable_t::iterator lower = function_symtable.lower_bound(symbol->function_name);

   993 	function_symtable_t::iterator upper = function_symtable.upper_bound(symbol->function_name);

   994 

   995 	if (NULL != symbol->formal_param_list)

   996 		parameter_list = (list_c *)symbol->formal_param_list;

   997 	else if (NULL != symbol->nonformal_param_list)

   998 		parameter_list = (list_c *)symbol->nonformal_param_list;

   999 	else ERROR;

  1000 	for(; lower != upper; lower++) {

  1001 		f_decl = function_symtable.get_value(lower);

  1002 		symbol_c * return_type = base_type(f_decl->type_name);

  1003 		if (return_type && typeid(*symbol->datatype) != typeid(*return_type))

  1004 			continue;

  1005 		/* We set which function declaration it'll use in STAGE4 */

  1006 		symbol->called_function_declaration = f_decl;

  1007 		/* Check if function declaration in symbol_table is compatible with parameters */

  1008 		if (NULL != symbol->nonformal_param_list)

  1009 			/* nonformal parameter function call */

  1010 			narrow_nonformal_call(symbol, f_decl);

  1011 		else

  1012 			/* formal parameter function call */

  1013 			narrow_formal_call (symbol, f_decl);

  1014 		break;

  1015 	}

  1016 

  1017 	return NULL;

  1018 }

  1019 

  1020 /********************/

  1021 /* B 3.2 Statements */

  1022 /********************/

  1023 

  1024 

  1025 /*********************************/

  1026 /* B 3.2.1 Assignment Statements */

  1027 /*********************************/

  1028 

  1029 void *narrow_candidate_datatypes_c::visit(assignment_statement_c *symbol) {

  1030 	if (symbol->candidate_datatypes.size() != 1)

  1031 		return NULL;

  1032 	symbol->datatype = symbol->candidate_datatypes[0];

  1033 	symbol->l_exp->datatype = symbol->datatype;

  1034 	symbol->l_exp->accept(*this);

  1035 	symbol->r_exp->datatype = symbol->datatype;

  1036 	symbol->r_exp->accept(*this);

  1037 	return NULL;

  1038 }

  1039 

  1040 

  1041 /*****************************************/

  1042 /* B 3.2.2 Subprogram Control Statements */

  1043 /*****************************************/

  1044 

  1045 /********************************/

  1046 /* B 3.2.3 Selection Statements */

  1047 /********************************/

  1048 

  1049 void *narrow_candidate_datatypes_c::visit(if_statement_c *symbol) {

  1050 	for(unsigned int i = 0; i < symbol->expression->candidate_datatypes.size(); i++) {

  1051 		if (is_type(symbol->expression->candidate_datatypes[i], bool_type_name_c))

  1052 			symbol->expression->datatype = symbol->expression->candidate_datatypes[i];

  1053 	}

  1054 	symbol->expression->accept(*this);

  1055 	if (NULL != symbol->statement_list)

  1056 		symbol->statement_list->accept(*this);

  1057 	if (NULL != symbol->elseif_statement_list)

  1058 		symbol->elseif_statement_list->accept(*this);

  1059 	if (NULL != symbol->else_statement_list)

  1060 		symbol->else_statement_list->accept(*this);

  1061 	return NULL;

  1062 }

  1063 

  1064 

  1065 void *narrow_candidate_datatypes_c::visit(elseif_statement_c *symbol) {

  1066 	for (unsigned int i = 0; i < symbol->expression->candidate_datatypes.size(); i++) {

  1067 		if (is_type(symbol->expression->candidate_datatypes[i], bool_type_name_c))

  1068 			symbol->expression->datatype = symbol->expression->candidate_datatypes[i];

  1069 	}

  1070 	symbol->expression->accept(*this);

  1071 	if (NULL != symbol->statement_list)

  1072 		symbol->statement_list->accept(*this);

  1073 	return NULL;

  1074 }

  1075 

  1076 /* CASE expression OF case_element_list ELSE statement_list END_CASE */

  1077 // SYM_REF3(case_statement_c, expression, case_element_list, statement_list)

  1078 void *narrow_candidate_datatypes_c::visit(case_statement_c *symbol) {

  1079 	for (unsigned int i = 0; i < symbol->expression->candidate_datatypes.size(); i++) {

  1080 		if ((is_ANY_INT_type(symbol->expression->candidate_datatypes[i]))

  1081 				 || (search_base_type.type_is_enumerated(symbol->expression->candidate_datatypes[i])))

  1082 			symbol->expression->datatype = symbol->expression->candidate_datatypes[i];

  1083 	}

  1084 	symbol->expression->accept(*this);

  1085 	if (NULL != symbol->statement_list)

  1086 		symbol->statement_list->accept(*this);

  1087 	if (NULL != symbol->case_element_list) {

  1088 		symbol->case_element_list->datatype = symbol->expression->datatype;

  1089 		symbol->case_element_list->accept(*this);

  1090 	}

  1091 	return NULL;

  1092 }

  1093 

  1094 /* helper symbol for case_statement */

  1095 // SYM_LIST(case_element_list_c)

  1096 void *narrow_candidate_datatypes_c::visit(case_element_list_c *symbol) {

  1097 	for (int i = 0; i < symbol->n; i++) {

  1098 		symbol->elements[i]->datatype = symbol->datatype;

  1099 		symbol->elements[i]->accept(*this);

  1100 	}

  1101 	return NULL;

  1102 }

  1103 

  1104 /*  case_list ':' statement_list */

  1105 // SYM_REF2(case_element_c, case_list, statement_list)

  1106 void *narrow_candidate_datatypes_c::visit(case_element_c *symbol) {

  1107 	symbol->case_list->datatype = symbol->datatype;

  1108 	symbol->case_list->accept(*this);

  1109 	symbol->statement_list->accept(*this);

  1110 	return NULL;

  1111 }

  1112 

  1113 // SYM_LIST(case_list_c)

  1114 void *narrow_candidate_datatypes_c::visit(case_list_c *symbol) {

  1115 	for (int i = 0; i < symbol->n; i++) {

  1116 		for (unsigned int k = 0; k < symbol->elements[i]->candidate_datatypes.size(); k++) {

  1117 			if (is_type_equal(symbol->datatype, symbol->elements[i]->candidate_datatypes[k]))

  1118 				symbol->elements[i]->datatype = symbol->elements[i]->candidate_datatypes[k];

  1119 		}

  1120 		/* NOTE: this may be an integer, a subrange_c, or a enumerated value! */

  1121 		symbol->elements[i]->accept(*this);

  1122 	}

  1123 	return NULL;

  1124 }

  1125 

  1126 

  1127 /********************************/

  1128 /* B 3.2.4 Iteration Statements */

  1129 /********************************/

  1130 void *narrow_candidate_datatypes_c::visit(for_statement_c *symbol) {

  1131 	/* Control variable */

  1132 	for(unsigned int i = 0; i < symbol->control_variable->candidate_datatypes.size(); i++) {

  1133 		if (is_ANY_INT_type(symbol->control_variable->candidate_datatypes[i])) {

  1134 			symbol->control_variable->datatype = symbol->control_variable->candidate_datatypes[i];

  1135 		}

  1136 	}