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/*

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 *  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)

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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

     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

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 *  (at your option) any later version.

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 *

    13

 *  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.

    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

 *

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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.

    24

 */

    25

    26

/*

    27

 * An IEC 61131-3 compiler.

    28

 *

    29

 * Based on the

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

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 *

    32

 */

    33

    34

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/*

    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>

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#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

    58

/* Only set the symbol's desired datatype to 'datatype' if that datatype is in the candidate_datatype list */

    59

static void set_datatype(symbol_c *datatype, symbol_c *symbol) {

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	symbol->datatype = NULL;   

    61

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

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		symbol->datatype = datatype;  

    63

}

    64

    65

    66

    67

    68

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[]) {

    69

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

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

    71

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

    72

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

    73

			return true;

    74

		}

    75

	}

    76

	return false;

    77

}

    78

    79

/*

    80

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

    81

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

    82

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

    83

 */

    84

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

    85

	symbol_c *call_param_value,  *param_type;

    86

	identifier_c *param_name;

    87

	function_param_iterator_c       fp_iterator(f_decl);

    88

	function_call_param_iterator_c fcp_iterator(f_call);

    89

	int extensible_parameter_highest_index = -1;

    90

	unsigned int i;

    91

    92

	if (NULL != ext_parm_count) *ext_parm_count = -1;

    93

    94

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

    95

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

    96

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

    97

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

    98

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

    99

		 */

   100

		do {

   101

			param_name = fp_iterator.next();

   102

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

   103

			/* This error should have been caught in fill_candidate_datatypes_c, but may occur here again when we handle FB invocations! 

   104

			 * In this case, we carry on analysing the code in order to be able to provide relevant error messages

   105

			 * for that code too!

   106

			 */

   107

			if(param_name == NULL) break;

   108

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

   109

   110

		/* Set the desired datatype for this parameter, and call it recursively. */

   111

		/* Note that if the call has more parameters than those declared in the function/FB declaration,

   112

		 * we may be setting this to NULL!

   113

		 */

   114

		symbol_c *desired_datatype = base_type(fp_iterator.param_type());

   115

		if ((NULL != param_name) && (NULL == desired_datatype)) ERROR;

   116

		if ((NULL == param_name) && (NULL != desired_datatype)) ERROR;

   117

   118

		/* NOTE: When we are handling a nonformal function call made from IL, the first parameter is the 'default' or 'current'

   119

		 *       il value. However, a pointer to the prev_il_instruction is pre-pended into the operand list (done in fill_candidate_datatypes_c,

   120

		 *       and later undone in print_datatypes_error_c - this class is run after the first, and before the latter!), so 

   121

		 *       the call 

   122

		 *       call_param_value->accept(*this);

   123

		 *       may actually be calling an object of the il_instruction_c class.

   124

		 *       If that is the case, that same il_instruction_c object will be called again inside the for() loop

   125

		 *       of void *narrow_candidate_datatypes_c::visit(instruction_list_c *symbol);

   129

		 */

   130

		set_datatype(desired_datatype, call_param_value);

   133

   134

		if (NULL != param_name) 

   135

			if (extensible_parameter_highest_index < fp_iterator.extensible_param_index())

   136

				extensible_parameter_highest_index = fp_iterator.extensible_param_index();

   137

	}

   138

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

   139

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

   140

	 * of the function call itself!

   141

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

   142

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

   143

	 * output code.

   144

	 */

   145

	if ((NULL != ext_parm_count) && (extensible_parameter_highest_index >=0) /* if call to extensible function */)

   146

		*ext_parm_count = 1 + extensible_parameter_highest_index - fp_iterator.first_extensible_param_index();

   147

}

   148

   149

   150

   151

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

   152

	symbol_c *call_param_value, *call_param_name, *param_type;

   153

	symbol_c *verify_duplicate_param;

   154

	identifier_c *param_name;

   155

	function_param_iterator_c       fp_iterator(f_decl);

   156

	function_call_param_iterator_c fcp_iterator(f_call);

   157

	int extensible_parameter_highest_index = -1;

   158

	identifier_c *extensible_parameter_name;

   159

	unsigned int i;

   160

   161

	if (NULL != ext_parm_count) *ext_parm_count = -1;

   162

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

   163

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

   164

   165

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

   166

		call_param_value = fcp_iterator.get_current_value();

   167

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

   168

		if (NULL == call_param_value) ERROR;

   169

   170

		/* Find the corresponding parameter in function declaration */

   171

		param_name = fp_iterator.search(call_param_name);

   172

   173

		/* Set the desired datatype for this parameter, and call it recursively. */

   174

		/* NOTE: When handling a FB call, this narrow_formal_call() may be called to analyse

   175

		 *       an invalid FB call (call with parameters that do not exist on the FB declaration).

   176

		 *       For this reason, the param_name may come out as NULL!

   177

		 */

   178

		symbol_c *desired_datatype = base_type(fp_iterator.param_type());

   179

		if ((NULL != param_name) && (NULL == desired_datatype)) ERROR;

   180

		if ((NULL == param_name) && (NULL != desired_datatype)) ERROR;

   181

   183

		set_datatype(desired_datatype, call_param_value);

   191

   192

		if (NULL != param_name) 

   193

			if (extensible_parameter_highest_index < fp_iterator.extensible_param_index())

   194

				extensible_parameter_highest_index = fp_iterator.extensible_param_index();

   195

	}

   196

	/* call is compatible! */

   197

   198

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

   199

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

   200

	 * of the function call itself!

   201

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

   202

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

   203

	 * output code.

   204

	 */

   205

	if ((NULL != ext_parm_count) && (extensible_parameter_highest_index >=0) /* if call to extensible function */)

   206

		*ext_parm_count = 1 + extensible_parameter_highest_index - fp_iterator.first_extensible_param_index();

   207

}

   208

   209

   210

/*

   211

typedef struct {

   212

  symbol_c *function_name,

   213

  symbol_c *nonformal_operand_list,

   214

  symbol_c *   formal_operand_list,

   215

   216

  std::vector <symbol_c *> &candidate_functions,  

   217

  symbol_c &*called_function_declaration,

   218

  int      &extensible_param_count

   219

} generic_function_call_t;

   220

*/

   221

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

   222

	/* set the called_function_declaration. */

   223

	fcall_data.called_function_declaration = NULL;

   224

   225

	/* set the called_function_declaration taking into account the datatype that we need to return */

   226

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

   227

		if (is_type_equal(fcall->candidate_datatypes[i], fcall->datatype)) {

   228

			fcall_data.called_function_declaration = fcall_data.candidate_functions[i];

   229

			break;

   230

		}

   231

	}

   232

   233

	/* NOTE: If we can't figure out the declaration of the function being called, this is not 

   234

	 *       necessarily an internal compiler error. It could be because the symbol->datatype is NULL

   235

	 *       (because the ST code being analysed has an error _before_ this function invocation).

   236

	 *       However, we don't just give, up, we carry on recursivly analysing the code, so as to be

   237

	 *       able to print out any error messages related to the parameters being passed in this function 

   238

	 *       invocation.

   239

	 */

   240

	/* if (NULL == symbol->called_function_declaration) ERROR; */

   241

	if (fcall->candidate_datatypes.size() == 1) {

   242

		/* If only one function declaration, then we use that (even if symbol->datatypes == NULL)

   243

		 * so we can check for errors in the expressions used to pass parameters in this

   244

		 * function invocation.

   245

		 */

   246

		fcall_data.called_function_declaration = fcall_data.candidate_functions[0];

   247

	}

   248

   249

	/* If an overloaded function is being invoked, and we cannot determine which version to use,

   250

	 * then we can not meaningfully verify the expressions used inside that function invocation.

   251

	 * We simply give up!

   252

	 */

   253

	if (NULL == fcall_data.called_function_declaration)

   254

		return;

   255

   256

	if (NULL != fcall_data.nonformal_operand_list)  narrow_nonformal_call(fcall, fcall_data.called_function_declaration, &(fcall_data.extensible_param_count));

   257

	if (NULL != fcall_data.   formal_operand_list)     narrow_formal_call(fcall, fcall_data.called_function_declaration, &(fcall_data.extensible_param_count));

   258

   259

	return;

   260

}

   261

   262

   263

   264

   265

/* narrow implicit FB call in IL.

   266

 * e.g.  CLK ton_var

   267

 *        CU counter_var

   268

 *

   269

 * The algorithm will be to build a fake il_fb_call_c equivalent to the implicit IL FB call, and let 

   270

 * the visit(il_fb_call_c *) method handle it!

   271

 */

   272

void narrow_candidate_datatypes_c::narrow_implicit_il_fb_call(symbol_c *il_instruction, const char *param_name, symbol_c *&called_fb_declaration) {

   273

	if (NULL == called_fb_declaration)

   274

		/* The fill_candidate_datatypes_c was not able to determine which FB is being called!

   275

		 * This may be because the il_operand is not the name of a FB instance, or no operand was given. 

   276

		 * In that case, we just give up!

   277

		 */

   278

		return;

   279

	if (NULL == prev_il_instruction) {

   280

		/* This IL implicit FB call (e.g. CLK ton_var) is not preceded by another IL instruction

   281

		 * (or list of instructions) that will set the IL current/default value.

   282

		 * We cannot proceed verifying type compatibility of something that does not ecist.

   283

		 */

   284

		return;

   285

	}

   286

   287

	identifier_c variable_name(param_name);

   288

	// SYM_REF1(il_assign_operator_c, variable_name)

   289

	il_assign_operator_c il_assign_operator(&variable_name);  

   290

	// SYM_REF3(il_param_assignment_c, il_assign_operator, il_operand, simple_instr_list)

   291

	il_param_assignment_c il_param_assignment(&il_assign_operator, prev_il_instruction/*il_operand*/, NULL);

   292

	il_param_list_c il_param_list;

   293

	il_param_list.add_element(&il_param_assignment);

   294

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

   295

	il_fb_call_c il_fb_call(NULL, il_operand, NULL, &il_param_list);

   296

   297

	/* A FB call does not return any datatype, but the IL instructions that come after this

   298

	 * FB call may require a specific datatype in the il current/default variable, 

   299

	 * so we must pass this information up to the IL instruction before the FB call, since it will

   300

	 * be that IL instruction that will be required to produce the desired dtataype.

   301

	 *

   302

	 * The above will be done by the visit(il_fb_call_c *) method, so we must make sure to

   303

	 * correctly set up the il_fb_call.datatype variable!

   304

	 */

   305

	copy_candidate_datatype_list(il_instruction/*from*/, &il_fb_call/*to*/);

   306

	il_fb_call.datatype = il_instruction->datatype;

   307

	il_fb_call.accept(*this);

   308

	il_instruction->datatype = il_fb_call.datatype;

   309

}

   310

   311

   312

/* a helper function... */

   313

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

   314

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

   315

	 *       in the code.

   316

	 */

   317

	if (symbol == NULL) return NULL;

   318

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

   319

}

   320

   321

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

   322

/* B 1.2 - Constants */

   323

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

   324

   325

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

   326

/* B 1.3 - Data types */

   327

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

   328

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

   329

/* B 1.3.3 - Derived data types */

   330

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

   331

/*  signed_integer DOTDOT signed_integer */

   332

// SYM_REF2(subrange_c, lower_limit, upper_limit)

   333

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

   334

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

   335

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

   336

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

   337

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

   338

	return NULL;

   339

}

   340

   341

/* simple_specification ASSIGN constant */

   342

// SYM_REF2(simple_spec_init_c, simple_specification, constant)

   343

void *narrow_candidate_datatypes_c::visit(simple_spec_init_c *symbol) {

   344

	symbol_c *datatype = base_type(symbol->simple_specification); 

   345

	if (NULL != symbol->constant) {

   346

		int typeoffset = search_in_candidate_datatype_list(datatype, symbol->constant->candidate_datatypes);

   347

		if (typeoffset >= 0)

   348

			symbol->constant->datatype = symbol->constant->candidate_datatypes[typeoffset];

   349

	}

   350

	return NULL;

   351

}

   352

   353

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

   354

/* B 1.4 - Variables */

   355

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

   356

   357

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

   358

/* B 1.4.1 - Directly Represented Variables */

   359

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

   360

   361

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

   362

/* B 1.4.2 - Multi-element variables */

   363

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

   364

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

   365

// SYM_REF2(array_variable_c, subscripted_variable, subscript_list)

   366

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

   367

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

   368

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

   369

	return NULL;

   370

}

   371

   372

   373

/* subscript_list ',' subscript */

   374

// SYM_LIST(subscript_list_c)

   375

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

   376

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

   377

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

   378

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

   379

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

   380

		}

   381

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

   382

	}

   383

	return NULL;  

   384

}

   385

   386

   387

   388

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

   389

/* B 1.5 Program organization units */

   390

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

   391

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

   392

/* B 1.5.1 Functions */

   393

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

   394

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

   395

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   396

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

   397

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

   398

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

   399

	delete search_varfb_instance_type;

   400

	search_varfb_instance_type = NULL;

   401

	return NULL;

   402

}

   403

   404

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

   405

/* B 1.5.2 Function blocks */

   406

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

   407

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

   408

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   409

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

   410

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

   411

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

   412

	delete search_varfb_instance_type;

   413

	search_varfb_instance_type = NULL;

   414

	return NULL;

   415

}

   416

   417

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

   418

/* B 1.5.3 Programs */

   419

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

   420

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

   421

	search_varfb_instance_type = new search_varfb_instance_type_c(symbol);

   422

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

   423

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

   424

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

   425

	delete search_varfb_instance_type;

   426

	search_varfb_instance_type = NULL;

   427

	return NULL;

   428

}

   429

   430

   431

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

   432

/* B 1.7 Configuration elements */

   433

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

   434

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

   435

	// TODO !!!

   436

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

   437

	return NULL;

   438

}

   439

   440

   441

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

   442

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

   443

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

   444

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

   445

/* B 2.1 Instructions and Operands */

   446

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

   447

   448

/*| instruction_list il_instruction */

   449

// SYM_LIST(instruction_list_c)

   450

void *narrow_candidate_datatypes_c::visit(instruction_list_c *symbol) {

   454

	for(int i = symbol->n-1; i >= 0; i--) {

   455

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

   456

	}

   457

	return NULL;

   458

}

   459

   460

/* | label ':' [il_incomplete_instruction] eol_list */

   461

// SYM_REF2(il_instruction_c, label, il_instruction)

   462

// void *visit(instruction_list_c *symbol);

   463

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

   464

	if (NULL == symbol->il_instruction) {

   465

		/* this empty/null il_instruction cannot generate the desired datatype. We pass on the request to the previous il instruction. */

   466

		if (NULL != symbol->prev_il_instruction)

   467

			symbol->prev_il_instruction->datatype = symbol->datatype;

   468

	} else {

   469

		/* Tell the il_instruction the datatype that it must generate - this was chosen by the next il_instruction (remember: we are iterating backwards!) */

   470

		symbol->il_instruction->datatype = symbol->datatype;

   472

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

   477

   478

   479

   480

   481

// void *visit(instruction_list_c *symbol);

   482

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

   483

	/* Tell the il_simple_operator the datatype that it must generate - this was chosen by the next il_instruction (we iterate backwards!) */

   484

	symbol->il_simple_operator->datatype = symbol->datatype;

   485

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

   486

	il_operand = symbol->il_operand;

   487

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

   488

	il_operand = NULL;

   489

	return NULL;

   490

}

   491

   492

/* | function_name [il_operand_list] */

   493

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

   494

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

   495

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

   496

	generic_function_call_t fcall_param = {

   497

		/* fcall_param.function_name               = */ symbol->function_name,

   498

		/* fcall_param.nonformal_operand_list      = */ symbol->il_operand_list,

   499

		/* fcall_param.formal_operand_list         = */ NULL,

   500

		/* enum {POU_FB, POU_function} POU_type    = */ generic_function_call_t::POU_function,

   501

		/* fcall_param.candidate_functions         = */ symbol->candidate_functions,

   502

		/* fcall_param.called_function_declaration = */ symbol->called_function_declaration,

   503

		/* fcall_param.extensible_param_count      = */ symbol->extensible_param_count

   504

	};

   505

   506

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

   507

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