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  (conti.ma@alice.it)

     6

 *

     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

/* Expressions on the left hand side of assignment statements have aditional restrictions on their datatype.

    37

 * For example, they cannot be literals, CONSTANT type variables, function invocations, etc...

    38

 * This class wil do those checks.

    39

 * 

    40

 * Note that assignment may also be done when passing variables to OUTPUT or IN_OUT function parameters,so we check those too.

    41

 */

    42

    43

    44

    45

#include "lvalue_check.hh"

    46

    47

#define FIRST_(symbol1, symbol2) (((symbol1)->first_order < (symbol2)->first_order)   ? (symbol1) : (symbol2))

    48

#define  LAST_(symbol1, symbol2) (((symbol1)->last_order  > (symbol2)->last_order)    ? (symbol1) : (symbol2))

    49

    50

#define STAGE3_ERROR(error_level, symbol1, symbol2, ...) {                                                                  \

    51

  if (current_display_error_level >= error_level) {                                                                         \

    52

    fprintf(stderr, "%s:%d-%d..%d-%d: error: ",                                                                             \

    53

            FIRST_(symbol1,symbol2)->first_file, FIRST_(symbol1,symbol2)->first_line, FIRST_(symbol1,symbol2)->first_column,\

    54

                                                 LAST_(symbol1,symbol2) ->last_line,  LAST_(symbol1,symbol2) ->last_column);\

    55

    fprintf(stderr, __VA_ARGS__);                                                                                           \

    56

    fprintf(stderr, "\n");                                                                                                  \

    57

    error_count++;                                                                                                     \

    58

  }                                                                                                                         \

    59

}

    60

    61

    62

#define STAGE3_WARNING(symbol1, symbol2, ...) {                                                                             \

    63

    fprintf(stderr, "%s:%d-%d..%d-%d: warning: ",                                                                           \

    64

            FIRST_(symbol1,symbol2)->first_file, FIRST_(symbol1,symbol2)->first_line, FIRST_(symbol1,symbol2)->first_column,\

    65

                                                 LAST_(symbol1,symbol2) ->last_line,  LAST_(symbol1,symbol2) ->last_column);\

    66

    fprintf(stderr, __VA_ARGS__);                                                                                           \

    67

    fprintf(stderr, "\n");                                                                                                  \

    68

    warning_found = true;                                                                                                   \

    69

}

    70

    71

    72

lvalue_check_c::lvalue_check_c(symbol_c *ignore) {

    73

	error_count = 0;

    74

	current_display_error_level = 0;

    75

	current_il_operand = NULL;

    76

	search_varfb_instance_type = NULL;

    77

	search_var_instance_decl = NULL;

    78

}

    79

    80

lvalue_check_c::~lvalue_check_c(void) {

    81

}

    82

    83

int lvalue_check_c::get_error_count() {

    84

	return error_count;

    85

}

    86

    87

    88

#include <strings.h>

    89

/* No writing to iterator variables (used in FOR loops) inside the loop itself */

    90

void lvalue_check_c::check_assignment_to_controlvar(symbol_c *lvalue) {

    91

	for (unsigned int i = 0; i < control_variables.size(); i++) {

    92

		token_c *lvalue_name = get_var_name_c::get_name(lvalue);

    93

		if (compare_identifiers(lvalue_name, control_variables[i]) == 0) {

    94

			STAGE3_ERROR(0, lvalue, lvalue, "Assignment to FOR control variable is not allowed.");

    95

			break;

    96

		}

    97

	}

    98

}

    99

   100

   101

/* fb_instance.var := ...  is not valid if var is output variable */

   102

/* NOTE, if a fb_instance1.fb_instance2.fb_instance3.var is used, we must iteratively check that none of the 

   103

 *       FB records are declared as OUTPUT variables!!  

   104

 *       This is the reason why we have the while() loop in this function!

   105

 * 

   106

 *       Note, however, that the first record (fb_instance1 in the above example) may be an output variable!

   107

 */

   108

void lvalue_check_c::check_assignment_to_output(symbol_c *lvalue) {

   109

	decompose_var_instance_name_c decompose_lvalue(lvalue);

   110

   111

	/* Get the first element/record of the potentially structured variable symbol */

   112

	/* Note that if symbol is pointing to an expression (or simply a literal value), it will return a NULL.

   113

	 * Once we have implemented the check_assignment_to_expression() method, and abort calling the other checks (including this one)

   114

	 * when an expression is found, we may replace this check with an assertion...

   115

	 * if (NULL == struct_elem) ERROR;

   116

	 */

   117

	symbol_c *struct_elem = decompose_lvalue.get_next();

   118

	if (NULL == struct_elem) return;

   119

   120

	symbol_c *type_decl   = search_var_instance_decl->get_decl(struct_elem);

   121

	// symbol_c *type_id  = spec_init_sperator_c::get_spec(type_decl); /* this is not required! search_base_type_c can handle spec_init symbols! */

   122

	symbol_c *basetype_id = search_base_type_c::get_basetype_id(/*type_id*/ type_decl);

   123

	/* If we can not determine the data type of the element, then the code must have a data type semantic error.

   124

	 * This will have been caught by the data type semantic verifier, so we do not bother with this anymore!

   125

	 */

   126

	if (NULL == basetype_id) return;

   127

   128

	/* Determine if the record/structure element is of a FB type. */

   129

	/* NOTE: If the structure element is not a FB type, then we can quit this check.

   130

	 *       Remember that the standard does not allow a STRUCT data type to have elements that are FB instances!

   131

	 *       Similarly, arrays of FB instances is also not allowed.

   132

	 *       So, as soon as we find one record/structure element that is not a FB, no other record/structure element

   133

	 *       will be of FB type, which means we can quit this check!

   134

	 */

   135

	function_block_declaration_c *fb_decl = function_block_type_symtable.find_value(basetype_id);

   136

	if (function_block_type_symtable.end_value() == fb_decl) return;

   137

   138

	while (NULL != (struct_elem = decompose_lvalue.get_next())) {

   139

		search_var_instance_decl_c   fb_search_var_instance_decl(fb_decl);

   140

		if (search_var_instance_decl_c::output_vt == fb_search_var_instance_decl.get_vartype(struct_elem)) {

   141

			STAGE3_ERROR(0, struct_elem, struct_elem, "Assignment to FB output variable is not allowed.");

   142

			return; /* no need to carry on checking once the first error is found! */

   143

		}

   144

   145

		/* prepare for any possible further record/structure elements */

   146

		type_decl   = fb_search_var_instance_decl.get_decl(struct_elem);

   147

		basetype_id = search_base_type_c::get_basetype_id(type_decl);

   148

		if (NULL == basetype_id) return; /* same comment as above... */

   149

		fb_decl = function_block_type_symtable.find_value(basetype_id);

   150

		if (function_block_type_symtable.end_value() == fb_decl) return; /* same comment as above... */

   151

	}

   152

}

   153

   154

   155

/*  No writing to CONSTANTs */

   156

void lvalue_check_c::check_assignment_to_constant(symbol_c *lvalue) {

   157

	unsigned int option = search_var_instance_decl->get_option(lvalue);

   158

	if (option == search_var_instance_decl_c::constant_opt) {

   159

		STAGE3_ERROR(0, lvalue, lvalue, "Assignment to CONSTANT variables is not allowed.");

   160

	}

   161

}

   162

   163

   164

/*  No assigning values to expressions. */

   165

void lvalue_check_c::check_assignment_to_expression(symbol_c *lvalue) {

   166

	/* This may occur in function invocations, when passing values (possibly an expression) to one

   167

	 * of the function's OUTPUT or IN_OUT parameters.

   168

	 */

   169

	if ( 

   170

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

   171

	     /* B 1.2 - Constants */

   172

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

   173

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

   174

	     /* B 1.2.1 - Numeric Literals */

   175

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

   176

	     (typeid( *lvalue ) == typeid( real_c                         )) ||

   177

	     (typeid( *lvalue ) == typeid( integer_c                      )) ||

   178

	     (typeid( *lvalue ) == typeid( binary_integer_c               )) ||

   179

	     (typeid( *lvalue ) == typeid( octal_integer_c                )) ||

   180

	     (typeid( *lvalue ) == typeid( hex_integer_c                  )) ||

   181

	     (typeid( *lvalue ) == typeid( neg_real_c                     )) ||

   182

	     (typeid( *lvalue ) == typeid( neg_integer_c                  )) ||

   183

	     (typeid( *lvalue ) == typeid( integer_literal_c              )) ||

   184

	     (typeid( *lvalue ) == typeid( real_literal_c                 )) ||

   185

	     (typeid( *lvalue ) == typeid( bit_string_literal_c           )) ||

   186

	     (typeid( *lvalue ) == typeid( boolean_literal_c              )) ||

   187

	     (typeid( *lvalue ) == typeid( boolean_true_c                 )) || /* should not really be needed */

   188

	     (typeid( *lvalue ) == typeid( boolean_false_c                )) || /* should not really be needed */

   189

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

   190

	     /* B.1.2.2   Character Strings */

   191

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

   192

	     (typeid( *lvalue ) == typeid( double_byte_character_string_c )) ||

   193

	     (typeid( *lvalue ) == typeid( single_byte_character_string_c )) ||

   194

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

   195

	     /* B 1.2.3 - Time Literals */

   196

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

   197

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

   198

	     /* B 1.2.3.1 - Duration */

   199

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

   200

	     (typeid( *lvalue ) == typeid( duration_c                     )) ||

   201

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

   202

	     /* B 1.2.3.2 - Time of day and Date */

   203

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

   204

	     (typeid( *lvalue ) == typeid( time_of_day_c                  )) ||

   205

	     (typeid( *lvalue ) == typeid( daytime_c                      )) || /* should not really be needed */

   206

	     (typeid( *lvalue ) == typeid( date_c                         )) || /* should not really be needed */

   207

	     (typeid( *lvalue ) == typeid( date_literal_c                 )) ||

   208

	     (typeid( *lvalue ) == typeid( date_and_time_c                )) ||

   209

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

   210

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

   211

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

   212

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

   213

	     /* B 3.1 - Expressions */

   214

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

   215

	     (typeid( *lvalue ) == typeid( or_expression_c                )) ||

   216

	     (typeid( *lvalue ) == typeid( xor_expression_c               )) ||

   217

	     (typeid( *lvalue ) == typeid( and_expression_c               )) ||

   218

	     (typeid( *lvalue ) == typeid( equ_expression_c               )) ||

   219

	     (typeid( *lvalue ) == typeid( notequ_expression_c            )) ||

   220

	     (typeid( *lvalue ) == typeid( lt_expression_c                )) ||

   221

	     (typeid( *lvalue ) == typeid( gt_expression_c                )) ||

   222

	     (typeid( *lvalue ) == typeid( le_expression_c                )) ||

   223

	     (typeid( *lvalue ) == typeid( ge_expression_c                )) ||

   224

	     (typeid( *lvalue ) == typeid( add_expression_c               )) ||

   225

	     (typeid( *lvalue ) == typeid( sub_expression_c               )) ||

   226

	     (typeid( *lvalue ) == typeid( mul_expression_c               )) ||

   227

	     (typeid( *lvalue ) == typeid( div_expression_c               )) ||

   228

	     (typeid( *lvalue ) == typeid( mod_expression_c               )) ||

   229

	     (typeid( *lvalue ) == typeid( power_expression_c             )) ||

   230

	     (typeid( *lvalue ) == typeid( neg_expression_c               )) ||

   231

	     (typeid( *lvalue ) == typeid( not_expression_c               )) ||

   232

	     (typeid( *lvalue ) == typeid( function_invocation_c          )))

   233

		STAGE3_ERROR(0, lvalue, lvalue, "Assignment to an expression or a literal value is not allowed.");

   234

}                                                                  

   235

   236

   237

   238

/*  No assigning values to IL lists. */

   239

void lvalue_check_c::check_assignment_to_il_list(symbol_c *lvalue) {

   240

	/* This may occur in formal invocations in IL, where an embedded IL list may be used instead of a symbolic_variable

   241

	 * when passing an IN_OUT parameter! Note that it will never occur to OUT parameters, as the syntax does not allow it,

   242

	 * although this does not affect out algorithm here!

   243

	 */

   244

	if ( 

   245

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

   246

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

   247

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

   248

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

   249

	     /* B 2.1 Instructions and Operands */

   250

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

   251

	     (typeid( *lvalue ) == typeid( simple_instr_list_c)))

   252

		STAGE3_ERROR(0, lvalue, lvalue, "Assigning an IL list to an IN_OUT parameter is not allowed.");

   253

}                                                                  

   254

   255

   256

   257

   258

void lvalue_check_c::verify_is_lvalue(symbol_c *lvalue) {

   259

	if (NULL == lvalue) return; // missing operand in source code being compiled. Error will be caught and reported by datatype checking!

   260

	int init_error_count = error_count;  /* stop the checks once an error has been found... */

   261

	if (error_count == init_error_count)  check_assignment_to_expression(lvalue);

   262

	if (error_count == init_error_count)  check_assignment_to_il_list   (lvalue);

   263

	if (error_count == init_error_count)  check_assignment_to_controlvar(lvalue);

   264

	if (error_count == init_error_count)  check_assignment_to_output    (lvalue);

   265

	if (error_count == init_error_count)  check_assignment_to_constant  (lvalue);

   266

}

   267

   268

   269

   270

   271

/* check whether all values passed to OUT or IN_OUT parameters are legal lvalues. */

   272

/*

   273

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

   274

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

   275

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

   276

 */

   277

#include <string.h> /* required for strcmp() */

   278

void lvalue_check_c::check_nonformal_call(symbol_c *f_call, symbol_c *f_decl) {

   279

	/* if data type semantic verification was unable to determine which function is being called,

   280

	 * then it does not make sense to go ahead and check for lvalues to unknown parameters.

   281

	 * We simply bug out!

   282

	 */

   283

	if (NULL == f_decl) return;

   284

   285

	symbol_c *call_param_value;

   286

	identifier_c *param_name;

   287

	function_param_iterator_c       fp_iterator(f_decl);

   288

	function_call_param_iterator_c fcp_iterator(f_call);

   289

   290

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

   291

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

   292

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

   293

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

   294

		 */

   295

		do {

   296

			param_name = fp_iterator.next();

   297

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

   298

			/* This error should have been caught in data type verification, so we simply abandon our check! */

   299

			if(param_name == NULL) return;

   300

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

   301

   302

		/* Determine the direction (IN, OUT, IN_OUT) of the parameter... */

   303

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

   304

   305

		/* We only process the parameter value if the paramater itself is valid... */

   306

		if (param_name != NULL) {

   307

			/* If the parameter is either OUT or IN_OUT, we check if 'call_param_value' is a valid lvalue */

   308

			if ((function_param_iterator_c::direction_out == param_direction) || (function_param_iterator_c::direction_inout == param_direction)) 

   309

				verify_is_lvalue(call_param_value);

   310

			/* parameter values to IN  parameters may be expressions with function invocations that must also be checked! */

   311

			/* parameter values to OUT or IN_OUT parameters may contain arrays, whose subscripts contain expressions that must be checked! */

   312

			call_param_value->accept(*this);  

   313

		}

   314

	}

   315

}

   316

   317

   318

   319

   320

   321

   322

/* check whether all values passed to OUT or IN_OUT parameters are legal lvalues. */

   323

void lvalue_check_c::check_formal_call(symbol_c *f_call, symbol_c *f_decl) {

   324

	/* if data type semantic verification was unable to determine which function is being called,

   325

	 * then it does not make sense to go ahead and check for lvalues to unknown parameters.

   326

	 * We simply bug out!

   327

	 */

   328

	if (NULL == f_decl) return;

   329

   330

	symbol_c *call_param_name;

   331

	function_param_iterator_c       fp_iterator(f_decl);

   332

	function_call_param_iterator_c fcp_iterator(f_call);

   333

   334

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

   335

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

   336

   337

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

   338

		symbol_c *call_param_value = fcp_iterator.get_current_value();

   339

		if (NULL == call_param_value) ERROR;

   340

   341

		/* Find the corresponding parameter in function declaration, and it's direction (IN, OUT, IN_OUT) */

   342

		identifier_c *param_name = fp_iterator.search(call_param_name);

   343

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

   344

   345

		/* We only process the parameter value if the paramater itself is valid... */

   346

		if (param_name != NULL) {

   347

			/* If the parameter is either OUT or IN_OUT, we check if 'call_param_value' is a valid lvalue */

   348

			if ((function_param_iterator_c::direction_out == param_direction) || (function_param_iterator_c::direction_inout == param_direction)) 

   349

				verify_is_lvalue(call_param_value);

   350

			/* parameter values to IN  parameters may be expressions with function invocations that must also be checked! */

   351

			/* parameter values to OUT or IN_OUT parameters may contain arrays, whose subscripts contain expressions that must be checked! */

   352

			call_param_value->accept(*this);  

   353

 		}

   354

	}

   355

}

   356

   357

   358

   359

   360

   361

   362

   363

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

   364

/* B 1.5 - Program organisation units */

   365

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

   366

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

   367

/* B 1.5.1 - Functions */

   368

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

   369

void *lvalue_check_c::visit(function_declaration_c *symbol) {

   370

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   371

	search_var_instance_decl = new search_var_instance_decl_c(symbol);

   372

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

   373

	delete search_varfb_instance_type;

   374

	delete search_var_instance_decl;

   375

	search_varfb_instance_type = NULL;

   376

	search_var_instance_decl = NULL;

   377

	return NULL;

   378

}

   379

   380

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

   381

/* B 1.5.2 - Function blocks */

   382

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

   383

void *lvalue_check_c::visit(function_block_declaration_c *symbol) {

   384

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   385

	search_var_instance_decl = new search_var_instance_decl_c(symbol);

   386

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

   387

	delete search_varfb_instance_type;

   388

	delete search_var_instance_decl;

   389

	search_varfb_instance_type = NULL;

   390

	search_var_instance_decl = NULL;

   391

	return NULL;

   392

}

   393

   394

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

   395

/* B 1.5.3 - Programs */

   396

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

   397

void *lvalue_check_c::visit(program_declaration_c *symbol) {

   398

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   399

	search_var_instance_decl = new search_var_instance_decl_c(symbol);

   400

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

   401

	delete search_varfb_instance_type;

   402

	delete search_var_instance_decl;

   403

	search_varfb_instance_type = NULL;

   404

	search_var_instance_decl = NULL;

   405

	return NULL;

   406

}

   407

   408

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

   409

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

   410

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

   411

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

   412

/* B 2.1 Instructions and Operands */

   413

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

   414

void *lvalue_check_c::visit(il_instruction_c *symbol) {

   415

	/* il_instruction will be NULL when parsing a label with no instruction

   416

	 * e.g.:   label1:          <---- il_instruction = NULL!

   417

	 *                 LD 33

   418

	 *                 ...

   419

	 */

   420

	if (NULL != symbol->il_instruction)

   421

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

   422

	return NULL;

   423

}

   424

   425

void *lvalue_check_c::visit(il_simple_operation_c *symbol) {

   426

	current_il_operand = symbol->il_operand;

   427

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

   428

	current_il_operand = NULL;

   429

	return NULL;

   430

}

   431

   432

   433

   434

   435

/* | function_name [il_operand_list] */

   436

/* NOTE: The parameters 'called_function_declaration' and 'extensible_param_count' are used to pass data between the stage 3 and stage 4. */

   437

// SYM_REF2(il_function_call_c, function_name, il_operand_list, symbol_c *called_function_declaration; int extensible_param_count;)

   438

void *lvalue_check_c::visit(il_function_call_c *symbol) {

   439

	/* The first parameter of a non formal function call in IL will be the 'current value' (i.e. the prev_il_instruction)

   440

	 * In order to be able to handle this without coding special cases, we will simply prepend that symbol

   441

	 * to the il_operand_list, and remove it after calling handle_function_call().

   442

	 *

   443

	 * However, if no further paramters are given, then il_operand_list will be NULL, and we will

   444

	 * need to create a new object to hold the pointer to prev_il_instruction.

   445

	 * This change will also be undone at the end of this method.

   446

	 */

   447

	/* TODO: Copying the location data will result in confusing error message. 

   448

	 *       We need to make this better, by inserting code to handle this special situation explicitly!

   449

	 */

   450

	/* NOTE: When calling a function, using the 'current value' as the first parameter of the function invocation

   451

	 *       implies that we can only call functions whose first parameter is IN. It would not do to pass

   452

	 *       the 'current value' to an OUT or IN_OUT parameter.

   453

	 *       In order to make sure that this will be caught by the check_nonformal_call() function,

   454

	 *       we add a symbol that cannot be an lvalue; in this case, a real_c (REAL literal).

   455

	 */

   456

	real_c param_value(NULL);

   457

	*((symbol_c *)(&param_value)) = *((symbol_c *)symbol); /* copy the symbol location (file, line, offset) data */

   458

	if (NULL == symbol->il_operand_list)  symbol->il_operand_list = new il_operand_list_c;

   459

	if (NULL == symbol->il_operand_list)  ERROR;

   460

	((list_c *)symbol->il_operand_list)->insert_element(&param_value, 0);

   461

   462

	check_nonformal_call(symbol, symbol->called_function_declaration);

   463

   464

	/* Undo the changes to the abstract syntax tree we made above... */

   465

	((list_c *)symbol->il_operand_list)->remove_element(0);

   466

	if (((list_c *)symbol->il_operand_list)->n == 0) {

   467

		/* if the list becomes empty, then that means that it did not exist before we made these changes, so we delete it! */

   468

		delete 	symbol->il_operand_list;

   469

		symbol->il_operand_list = NULL;

   470

	}

   471

   472

	return NULL;

   473

}

   474

   475

   476

   477

   478

   479

   480

/*   il_call_operator prev_declared_fb_name

   481

 * | il_call_operator prev_declared_fb_name '(' ')'

   482

 * | il_call_operator prev_declared_fb_name '(' eol_list ')'

   483

 * | il_call_operator prev_declared_fb_name '(' il_operand_list ')'

   484

 * | il_call_operator prev_declared_fb_name '(' eol_list il_param_list ')'

   485

 */

   486

/* NOTE: The parameter 'called_fb_declaration'is used to pass data between stage 3 and stage4 (although currently it is not used in stage 4 */

   487

// SYM_REF4(il_fb_call_c, il_call_operator, fb_name, il_operand_list, il_param_list, symbol_c *called_fb_declaration)

   488

void *lvalue_check_c::visit(il_fb_call_c *symbol) {

   489

	if (NULL != symbol->il_operand_list)  check_nonformal_call(symbol, symbol->called_fb_declaration);

   490

	if (NULL != symbol->  il_param_list)     check_formal_call(symbol, symbol->called_fb_declaration);

   491

	return NULL;

   492

}

   493

   494

   495

/* | function_name '(' eol_list [il_param_list] ')' */

   496

/* NOTE: The parameter 'called_function_declaration' is used to pass data between the stage 3 and stage 4. */

   497

// SYM_REF2(il_formal_funct_call_c, function_name, il_param_list, symbol_c *called_function_declaration; int extensible_param_count;)

   498

void *lvalue_check_c::visit(il_formal_funct_call_c *symbol) {

   499

	check_formal_call(symbol, symbol->called_function_declaration);

   500

	return NULL;