--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/stage3/narrow_candidate_datatypes.cc Wed Aug 22 16:46:17 2012 +0200
@@ -0,0 +1,1328 @@
+/*
+ * matiec - a compiler for the programming languages defined in IEC 61131-3
+ *
+ * Copyright (C) 2009-2012 Mario de Sousa (msousa@fe.up.pt)
+ * Copyright (C) 2012 Manuele Conti (manuele.conti@sirius-es.it)
+ * Copyright (C) 2012 Matteo Facchinetti (matteo.facchinetti@sirius-es.it)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ *
+ * This code is made available on the understanding that it will not be
+ * used in safety-critical situations without a full and competent review.
+ */
+
+/*
+ * An IEC 61131-3 compiler.
+ *
+ * Based on the
+ * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
+ *
+ */
+
+
+/* NOTE: The algorithm implemented here assumes that candidate datatype lists have already been filled!
+ * BEFORE running this visitor, be sure to CALL the fill_candidate_datatype_c visitor!
+ */
+
+
+/*
+ * Choose, from the list of all the possible datatypes each expression may take, the single datatype that it will in fact take.
+ * The resulting (chosen) datatype, will be stored in the symbol_c.datatype variable, leaving the candidate datatype list untouched!
+ *
+ * For rvalue expressions, this decision will be based on the datatype of the lvalue expression.
+ * For lvalue expressions, the candidate datatype list should have a single entry.
+ *
+ * For example, the very simple literal '0' in 'foo := 0', may represent a:
+ * BOOL, BYTE, WORD, DWORD, LWORD, USINT, SINT, UINT, INT, UDINT, DINT, ULINT, LINT (as well as the SAFE versions of these data tyes too!)
+ *
+ * In this class, the datatype of '0' will be set to the same datatype as the 'foo' variable.
+ * If the intersection of the candidate datatype lists of the left and right side expressions is empty,
+ * then a datatype error has been found, and the datatype is either left at NULL, or set to a pointer of an invalid_type_name_c object!
+ */
+
+
+#include "narrow_candidate_datatypes.hh"
+#include "datatype_functions.hh"
+#include <typeinfo>
+#include <list>
+#include <string>
+#include <string.h>
+#include <strings.h>
+
+
+/* set to 1 to see debug info during execution */
+static int debug = 0;
+
+narrow_candidate_datatypes_c::narrow_candidate_datatypes_c(symbol_c *ignore) {
+}
+
+narrow_candidate_datatypes_c::~narrow_candidate_datatypes_c(void) {
+}
+
+
+/* Only set the symbol's desired datatype to 'datatype' if that datatype is in the candidate_datatype list */
+static void set_datatype(symbol_c *datatype, symbol_c *symbol) {
+
+ /* If we are trying to set to the undefined type, and the symbol's datatype has already been set to something else,
+ * we abort the compoiler as I don't think this should ever occur.
+ * NOTE: In order to handle JMPs to labels that come before the JMP itself, we run the narrow algorithm twice.
+ * This means that this situation may legally occur, so we cannot abort the compiler here!
+ */
+// if ((NULL == datatype) && (NULL != symbol->datatype)) ERROR;
+ if ((NULL == datatype) && (NULL != symbol->datatype)) return;
+ if ((NULL == datatype) && (NULL == symbol->datatype)) return;
+
+ if (search_in_candidate_datatype_list(datatype, symbol->candidate_datatypes) < 0)
+ symbol->datatype = &(search_constant_type_c::invalid_type_name);
+ else {
+ if (NULL == symbol->datatype)
+ /* not yet set to anything, so we set it to the requested data type */
+ symbol->datatype = datatype;
+ else {
+ /* had already been set previously to some data type. Let's check if they are the same! */
+ if (!is_type_equal(symbol->datatype, datatype))
+ symbol->datatype = &(search_constant_type_c::invalid_type_name);
+// else
+ /* we leave it unchanged, as it is the same as the requested data type! */
+ }
+ }
+}
+
+
+
+/* Only set the symbol's desired datatype to 'datatype' if that datatype is in the candidate_datatype list */
+// static void set_datatype_in_prev_il_instructions(symbol_c *datatype, std::vector <symbol_c *> prev_il_instructions) {
+static void set_datatype_in_prev_il_instructions(symbol_c *datatype, il_instruction_c *symbol) {
+ if (NULL == symbol) ERROR;
+ for (unsigned int i = 0; i < symbol->prev_il_instruction.size(); i++)
+ set_datatype(datatype, symbol->prev_il_instruction[i]);
+}
+
+
+
+bool narrow_candidate_datatypes_c::is_widening_compatible(const struct widen_entry widen_table[], symbol_c *left_type, symbol_c *right_type, symbol_c *result_type, bool *deprecated_status) {
+ /* NOTE: According to our algorithm, left_type and right_type should never by NULL (if they are, we have an internal compiler error!
+ * However, result_type may be NULL if the code has a data type semantic error!
+ */
+ if ((NULL == left_type) || (NULL == right_type) || (NULL == result_type))
+ return false;
+
+ for (int k = 0; NULL != widen_table[k].left; k++) {
+ if ((typeid(*left_type) == typeid(*widen_table[k].left))
+ && (typeid(*right_type) == typeid(*widen_table[k].right))
+ && (typeid(*result_type) == typeid(*widen_table[k].result))) {
+ if (NULL != deprecated_status)
+ *deprecated_status = (widen_table[k].status == widen_entry::deprecated);
+ return true;
+ }
+ }
+ return false;
+}
+
+/*
+ * All parameters being passed to the called function MUST be in the parameter list to which f_call points to!
+ * This means that, for non formal function calls in IL, de current (default value) must be artificially added to the
+ * beginning of the parameter list BEFORE calling handle_function_call().
+ */
+void narrow_candidate_datatypes_c::narrow_nonformal_call(symbol_c *f_call, symbol_c *f_decl, int *ext_parm_count) {
+ symbol_c *call_param_value, *param_type;
+ identifier_c *param_name;
+ function_param_iterator_c fp_iterator(f_decl);
+ function_call_param_iterator_c fcp_iterator(f_call);
+ int extensible_parameter_highest_index = -1;
+ unsigned int i;
+
+ if (NULL != ext_parm_count) *ext_parm_count = -1;
+
+ /* Iterating through the non-formal parameters of the function call */
+ while((call_param_value = fcp_iterator.next_nf()) != NULL) {
+ /* Obtaining the type of the value being passed in the function call */
+ /* Iterate to the next parameter of the function being called.
+ * Get the name of that parameter, and ignore if EN or ENO.
+ */
+ do {
+ param_name = fp_iterator.next();
+ /* If there is no other parameter declared, then we are passing too many parameters... */
+ /* This error should have been caught in fill_candidate_datatypes_c, but may occur here again when we handle FB invocations!
+ * In this case, we carry on analysing the code in order to be able to provide relevant error messages
+ * for that code too!
+ */
+ if(param_name == NULL) break;
+ } while ((strcmp(param_name->value, "EN") == 0) || (strcmp(param_name->value, "ENO") == 0));
+
+ /* Set the desired datatype for this parameter, and call it recursively. */
+ /* Note that if the call has more parameters than those declared in the function/FB declaration,
+ * we may be setting this to NULL!
+ */
+ symbol_c *desired_datatype = base_type(fp_iterator.param_type());
+ if ((NULL != param_name) && (NULL == desired_datatype)) ERROR;
+ if ((NULL == param_name) && (NULL != desired_datatype)) ERROR;
+
+ /* NOTE: When we are handling a nonformal function call made from IL, the first parameter is the 'default' or 'current'
+ * il value. However, a pointer to a copy of the prev_il_instruction is pre-pended into the operand list, so
+ * the call
+ * call_param_value->accept(*this);
+ * may actually be calling an object of the base symbol_c .
+ */
+ set_datatype(desired_datatype, call_param_value);
+ call_param_value->accept(*this);
+
+ if (NULL != param_name)
+ if (extensible_parameter_highest_index < fp_iterator.extensible_param_index())
+ extensible_parameter_highest_index = fp_iterator.extensible_param_index();
+ }
+ /* In the case of a call to an extensible function, we store the highest index
+ * of the extensible parameters this particular call uses, in the symbol_c object
+ * of the function call itself!
+ * In calls to non-extensible functions, this value will be set to -1.
+ * This information is later used in stage4 to correctly generate the
+ * output code.
+ */
+ if ((NULL != ext_parm_count) && (extensible_parameter_highest_index >=0) /* if call to extensible function */)
+ *ext_parm_count = 1 + extensible_parameter_highest_index - fp_iterator.first_extensible_param_index();
+}
+
+
+
+void narrow_candidate_datatypes_c::narrow_formal_call(symbol_c *f_call, symbol_c *f_decl, int *ext_parm_count) {
+ symbol_c *call_param_value, *call_param_name, *param_type;
+ symbol_c *verify_duplicate_param;
+ identifier_c *param_name;
+ function_param_iterator_c fp_iterator(f_decl);
+ function_call_param_iterator_c fcp_iterator(f_call);
+ int extensible_parameter_highest_index = -1;
+ identifier_c *extensible_parameter_name;
+ unsigned int i;
+
+ if (NULL != ext_parm_count) *ext_parm_count = -1;
+ /* Iterating through the formal parameters of the function call */
+ while((call_param_name = fcp_iterator.next_f()) != NULL) {
+
+ /* Obtaining the value being passed in the function call */
+ call_param_value = fcp_iterator.get_current_value();
+ /* the following should never occur. If it does, then we have a bug in our code... */
+ if (NULL == call_param_value) ERROR;
+
+ /* Find the corresponding parameter in function declaration */
+ param_name = fp_iterator.search(call_param_name);
+
+ /* Set the desired datatype for this parameter, and call it recursively. */
+ /* NOTE: When handling a FB call, this narrow_formal_call() may be called to analyse
+ * an invalid FB call (call with parameters that do not exist on the FB declaration).
+ * For this reason, the param_name may come out as NULL!
+ */
+ symbol_c *desired_datatype = base_type(fp_iterator.param_type());
+ if ((NULL != param_name) && (NULL == desired_datatype)) ERROR;
+ if ((NULL == param_name) && (NULL != desired_datatype)) ERROR;
+
+ /* set the desired data type for this parameter */
+ set_datatype(desired_datatype, call_param_value);
+ /* And recursively call that parameter/expression, so it can propagate that info */
+ call_param_value->accept(*this);
+
+ /* set the extensible_parameter_highest_index, which will be needed in stage 4 */
+ /* This value says how many extensible parameters are being passed to the standard function */
+ if (NULL != param_name)
+ if (extensible_parameter_highest_index < fp_iterator.extensible_param_index())
+ extensible_parameter_highest_index = fp_iterator.extensible_param_index();
+ }
+ /* call is compatible! */
+
+ /* In the case of a call to an extensible function, we store the highest index
+ * of the extensible parameters this particular call uses, in the symbol_c object
+ * of the function call itself!
+ * In calls to non-extensible functions, this value will be set to -1.
+ * This information is later used in stage4 to correctly generate the
+ * output code.
+ */
+ if ((NULL != ext_parm_count) && (extensible_parameter_highest_index >=0) /* if call to extensible function */)
+ *ext_parm_count = 1 + extensible_parameter_highest_index - fp_iterator.first_extensible_param_index();
+}
+
+
+/*
+typedef struct {
+ symbol_c *function_name,
+ symbol_c *nonformal_operand_list,
+ symbol_c * formal_operand_list,
+
+ std::vector <symbol_c *> &candidate_functions,
+ symbol_c &*called_function_declaration,
+ int &extensible_param_count
+} generic_function_call_t;
+*/
+void narrow_candidate_datatypes_c::narrow_function_invocation(symbol_c *fcall, generic_function_call_t fcall_data) {
+ /* set the called_function_declaration. */
+ fcall_data.called_function_declaration = NULL;
+
+ /* set the called_function_declaration taking into account the datatype that we need to return */
+ for(unsigned int i = 0; i < fcall->candidate_datatypes.size(); i++) {
+ if (is_type_equal(fcall->candidate_datatypes[i], fcall->datatype)) {
+ fcall_data.called_function_declaration = fcall_data.candidate_functions[i];
+ break;
+ }
+ }
+
+ /* NOTE: If we can't figure out the declaration of the function being called, this is not
+ * necessarily an internal compiler error. It could be because the symbol->datatype is NULL
+ * (because the ST code being analysed has an error _before_ this function invocation).
+ * However, we don't just give, up, we carry on recursivly analysing the code, so as to be
+ * able to print out any error messages related to the parameters being passed in this function
+ * invocation.
+ */
+ /* if (NULL == symbol->called_function_declaration) ERROR; */
+ if (fcall->candidate_datatypes.size() == 1) {
+ /* If only one function declaration, then we use that (even if symbol->datatypes == NULL)
+ * so we can check for errors in the expressions used to pass parameters in this
+ * function invocation.
+ */
+ fcall_data.called_function_declaration = fcall_data.candidate_functions[0];
+ }
+
+ /* If an overloaded function is being invoked, and we cannot determine which version to use,
+ * then we can not meaningfully verify the expressions used inside that function invocation.
+ * We simply give up!
+ */
+ if (NULL == fcall_data.called_function_declaration)
+ return;
+
+ if (NULL != fcall_data.nonformal_operand_list) narrow_nonformal_call(fcall, fcall_data.called_function_declaration, &(fcall_data.extensible_param_count));
+ if (NULL != fcall_data. formal_operand_list) narrow_formal_call(fcall, fcall_data.called_function_declaration, &(fcall_data.extensible_param_count));
+
+ return;
+}
+
+
+
+
+/* narrow implicit FB call in IL.
+ * e.g. CLK ton_var
+ * CU counter_var
+ *
+ * The algorithm will be to build a fake il_fb_call_c equivalent to the implicit IL FB call, and let
+ * the visit(il_fb_call_c *) method handle it!
+ */
+void *narrow_candidate_datatypes_c::narrow_implicit_il_fb_call(symbol_c *il_instruction, const char *param_name, symbol_c *&called_fb_declaration) {
+
+ /* set the datatype of the il_operand, this is, the FB being called! */
+ if (NULL != il_operand) {
+ /* only set it if it is in the candidate datatypes list! */
+ set_datatype(called_fb_declaration, il_operand);
+ il_operand->accept(*this);
+ }
+ symbol_c *fb_decl = il_operand->datatype;
+
+ if (0 == fake_prev_il_instruction->prev_il_instruction.size()) {
+ /* This IL implicit FB call (e.g. CLK ton_var) is not preceded by another IL instruction
+ * (or list of instructions) that will set the IL current/default value.
+ * We cannot proceed verifying type compatibility of something that does not exist.
+ */
+ return NULL;
+ }
+
+ if (NULL == fb_decl) {
+ /* the il_operand is a not FB instance */
+ /* so we simply pass on the required datatype to the prev_il_instructions */
+ /* The invalid FB invocation will be caught in the print_datatypes_error_c by analysing NULL value in il_operand->datatype! */
+ set_datatype_in_prev_il_instructions(il_instruction->datatype, fake_prev_il_instruction);
+ return NULL;
+ }
+
+
+ /* The value being passed to the 'param_name' parameter is actually the prev_il_instruction.
+ * However, we do not place that object directly in the fake il_param_list_c that we will be
+ * creating, since the visit(il_fb_call_c *) method will recursively call every object in that list.
+ * The il_prev_intruction object will be visited once we have handled this implici IL FB call
+ * (called from the instruction_list_c for() loop that works backwards). We DO NOT want to visit it twice.
+ * (Anyway, if we let the visit(il_fb_call_c *) recursively visit the current prev_il_instruction, this pointer
+ * would be changed to the IL instruction coming before the current prev_il_instruction! => things would get all messed up!)
+ * The easiest way to work around this is to simply use a new object, and copy the relevant details to that object!
+ */
+ symbol_c param_value = *fake_prev_il_instruction; /* copy the candidate_datatypes list ! */
+
+ identifier_c variable_name(param_name);
+ // SYM_REF1(il_assign_operator_c, variable_name)
+ il_assign_operator_c il_assign_operator(&variable_name);
+ // SYM_REF3(il_param_assignment_c, il_assign_operator, il_operand, simple_instr_list)
+ il_param_assignment_c il_param_assignment(&il_assign_operator, ¶m_value/*il_operand*/, NULL);
+ il_param_list_c il_param_list;
+ il_param_list.add_element(&il_param_assignment);
+ // SYM_REF4(il_fb_call_c, il_call_operator, fb_name, il_operand_list, il_param_list, symbol_c *called_fb_declaration)
+ CAL_operator_c CAL_operator;
+ il_fb_call_c il_fb_call(&CAL_operator, il_operand, NULL, &il_param_list);
+
+ /* A FB call does not return any datatype, but the IL instructions that come after this
+ * FB call may require a specific datatype in the il current/default variable,
+ * so we must pass this information up to the IL instruction before the FB call, since it will
+ * be that IL instruction that will be required to produce the desired dtataype.
+ *
+ * The above will be done by the visit(il_fb_call_c *) method, so we must make sure to
+ * correctly set up the il_fb_call.datatype variable!
+ */
+ il_fb_call.called_fb_declaration = called_fb_declaration;
+ il_fb_call.accept(*this);
+
+ /* set the required datatype of the previous IL instruction! */
+ /* NOTE:
+ * When handling these implicit IL calls, the parameter_value being passed to the FB parameter
+ * is actually the prev_il_instruction.
+ *
+ * However, since the FB call does not change the value in the current/default IL variable, this value
+ * must also be used ny the IL instruction coming after this FB call.
+ *
+ * This means that we have two consumers/users for the same value.
+ * We must therefore check whether the datatype required by the IL instructions following this FB call
+ * is the same as that required for the first parameter. If not, then we have a semantic error,
+ * and we set it to invalid_type_name.
+ *
+ * However, we only do that if:
+ * - The IL instruction that comes after this IL FB call actually asked this FB call for a specific
+ * datatype in the current/default vairable, once this IL FB call returns.
+ * However, sometimes, (for e.g., this FB call is the last in the IL list) the subsequent FB to not aks this
+ * FB call for any datatype. In that case, then the datatype required to pass to the first parameter of the
+ * FB call must be left unchanged!
+ */
+ if ((NULL == il_instruction->datatype) || (is_type_equal(param_value.datatype, il_instruction->datatype))) {
+ set_datatype_in_prev_il_instructions(param_value.datatype, fake_prev_il_instruction);
+ } else {
+ set_datatype_in_prev_il_instructions(&search_constant_type_c::invalid_type_name, fake_prev_il_instruction);
+ }
+ return NULL;
+}
+
+
+/* a helper function... */
+symbol_c *narrow_candidate_datatypes_c::base_type(symbol_c *symbol) {
+ /* NOTE: symbol == NULL is valid. It will occur when, for e.g., an undefined/undeclared symbolic_variable is used
+ * in the code.
+ */
+ if (symbol == NULL) return NULL;
+ return (symbol_c *)symbol->accept(search_base_type);
+}
+
+/*********************/
+/* B 1.2 - Constants */
+/*********************/
+
+/**********************/
+/* B 1.3 - Data types */
+/**********************/
+/********************************/
+/* B 1.3.3 - Derived data types */
+/********************************/
+/* simple_specification ASSIGN constant */
+// SYM_REF2(simple_spec_init_c, simple_specification, constant)
+void *narrow_candidate_datatypes_c::visit(simple_spec_init_c *symbol) {
+ if (symbol->candidate_datatypes.size() == 1)
+ symbol->datatype = symbol->candidate_datatypes[0];
+
+ if (symbol->simple_specification->candidate_datatypes.size() == 1)
+ symbol->simple_specification->datatype = symbol->simple_specification->candidate_datatypes[0];
+
+ if (NULL != symbol->constant) {
+ set_datatype(symbol->datatype, symbol->constant);
+ symbol->constant->accept(*this);
+ }
+ return NULL;
+}
+
+
+
+/* signed_integer DOTDOT signed_integer */
+// SYM_REF2(subrange_c, lower_limit, upper_limit)
+void *narrow_candidate_datatypes_c::visit(subrange_c *symbol) {
+ symbol->lower_limit->datatype = symbol->datatype;
+ symbol->lower_limit->accept(*this);
+ symbol->upper_limit->datatype = symbol->datatype;
+ symbol->upper_limit->accept(*this);
+ return NULL;
+}
+
+
+/*********************/
+/* B 1.4 - Variables */
+/*********************/
+
+/********************************************/
+/* B 1.4.1 - Directly Represented Variables */
+/********************************************/
+
+/*************************************/
+/* B 1.4.2 - Multi-element variables */
+/*************************************/
+/* subscripted_variable '[' subscript_list ']' */
+// SYM_REF2(array_variable_c, subscripted_variable, subscript_list)
+void *narrow_candidate_datatypes_c::visit(array_variable_c *symbol) {
+ /* we need to check the data types of the expressions used for the subscripts... */
+ symbol->subscript_list->accept(*this);
+ return NULL;
+}
+
+
+/* subscript_list ',' subscript */
+// SYM_LIST(subscript_list_c)
+void *narrow_candidate_datatypes_c::visit(subscript_list_c *symbol) {
+ for (int i = 0; i < symbol->n; i++) {
+ for (unsigned int k = 0; k < symbol->elements[i]->candidate_datatypes.size(); k++) {
+ if (is_ANY_INT_type(symbol->elements[i]->candidate_datatypes[k]))
+ symbol->elements[i]->datatype = symbol->elements[i]->candidate_datatypes[k];
+ }
+ symbol->elements[i]->accept(*this);
+ }
+ return NULL;
+}
+
+
+
+
+/******************************************/
+/* B 1.4.3 - Declaration & Initialisation */
+/******************************************/
+
+void *narrow_candidate_datatypes_c::visit(var1_list_c *symbol) {
+#if 0 /* We don't really need to set the datatype of each variable. We just check the declaration itself! */
+ for(int i = 0; i < symbol->n; i++) {
+ if (symbol->elements[i]->candidate_datatypes.size() == 1)
+ symbol->elements[i]->datatype = symbol->elements[i]->candidate_datatypes[0];
+ }
+#endif
+ return NULL;
+}
+
+
+/* AT direct_variable */
+// SYM_REF1(location_c, direct_variable)
+void *narrow_candidate_datatypes_c::visit(location_c *symbol) {
+ set_datatype(symbol->datatype, symbol->direct_variable);
+ symbol->direct_variable->accept(*this); /* currently does nothing! */
+ return NULL;
+}
+
+
+/* [variable_name] location ':' located_var_spec_init */
+/* variable_name -> may be NULL ! */
+// SYM_REF3(located_var_decl_c, variable_name, location, located_var_spec_init)
+void *narrow_candidate_datatypes_c::visit(located_var_decl_c *symbol) {
+ /* let the var_spec_init set its own symbol->datatype value */
+ symbol->located_var_spec_init->accept(*this);
+
+ if (NULL != symbol->variable_name)
+ set_datatype(symbol->located_var_spec_init->datatype, symbol->variable_name);
+
+ set_datatype(symbol->located_var_spec_init->datatype, symbol->location);
+ symbol->location->accept(*this);
+ return NULL;
+}
+
+
+/************************************/
+/* B 1.5 Program organization units */
+/************************************/
+/*********************/
+/* B 1.5.1 Functions */
+/*********************/
+void *narrow_candidate_datatypes_c::visit(function_declaration_c *symbol) {
+ search_varfb_instance_type = new search_varfb_instance_type_c(symbol);
+ symbol->var_declarations_list->accept(*this);
+ if (debug) printf("Narrowing candidate data types list in body of function %s\n", ((token_c *)(symbol->derived_function_name))->value);
+ symbol->function_body->accept(*this);
+ delete search_varfb_instance_type;
+ search_varfb_instance_type = NULL;
+ return NULL;
+}
+
+/***************************/
+/* B 1.5.2 Function blocks */
+/***************************/
+void *narrow_candidate_datatypes_c::visit(function_block_declaration_c *symbol) {
+ search_varfb_instance_type = new search_varfb_instance_type_c(symbol);
+ symbol->var_declarations->accept(*this);
+ if (debug) printf("Narrowing candidate data types list in body of FB %s\n", ((token_c *)(symbol->fblock_name))->value);
+ symbol->fblock_body->accept(*this);
+ delete search_varfb_instance_type;
+ search_varfb_instance_type = NULL;
+ return NULL;
+}
+
+/********************/
+/* B 1.5.3 Programs */
+/********************/
+void *narrow_candidate_datatypes_c::visit(program_declaration_c *symbol) {
+ search_varfb_instance_type = new search_varfb_instance_type_c(symbol);
+ symbol->var_declarations->accept(*this);
+ if (debug) printf("Narrowing candidate data types list in body of program %s\n", ((token_c *)(symbol->program_type_name))->value);
+ symbol->function_block_body->accept(*this);
+ delete search_varfb_instance_type;
+ search_varfb_instance_type = NULL;
+ return NULL;
+}
+
+
+/********************************/
+/* B 1.7 Configuration elements */
+/********************************/
+void *narrow_candidate_datatypes_c::visit(configuration_declaration_c *symbol) {
+ // TODO !!!
+ /* for the moment we must return NULL so semantic analysis of remaining code is not interrupted! */
+ return NULL;
+}
+
+
+/****************************************/
+/* B.2 - Language IL (Instruction List) */
+/****************************************/
+/***********************************/
+/* B 2.1 Instructions and Operands */
+/***********************************/
+
+/*| instruction_list il_instruction */
+// SYM_LIST(instruction_list_c)
+void *narrow_candidate_datatypes_c::visit(instruction_list_c *symbol) {
+ /* In order to execute the narrow algoritm correctly, we need to go through the instructions backwards,
+ * so we can not use the base class' visitor
+ */
+ /* In order to execute the narrow algoritm correctly
+ * in IL instruction lists containing JMPs to labels that come before the JMP instruction
+ * itself, we need to run the narrow algorithm twice on the Instruction List.
+ * e.g.: ...
+ * ld 23
+ * label1:st byte_var
+ * ld 34
+ * JMP label1
+ *
+ * Note that the second time we run the narrow, most of the datatypes are already filled
+ * in, so it will be able to produce tha correct datatypes for the IL instruction referenced
+ * by the label, as in the 2nd pass we already know the datatypes of the JMP instruction!
+ */
+ for(int j = 0; j < 2; j++) {
+ for(int i = symbol->n-1; i >= 0; i--) {
+ symbol->elements[i]->accept(*this);
+ }
+ }
+ return NULL;
+}
+
+/* | label ':' [il_incomplete_instruction] eol_list */
+// SYM_REF2(il_instruction_c, label, il_instruction)
+// void *visit(instruction_list_c *symbol);
+void *narrow_candidate_datatypes_c::visit(il_instruction_c *symbol) {
+ if (NULL == symbol->il_instruction) {
+ /* this empty/null il_instruction cannot generate the desired datatype. We pass on the request to the previous il instruction. */
+ set_datatype_in_prev_il_instructions(symbol->datatype, symbol);
+ } else {
+ il_instruction_c tmp_prev_il_instruction(NULL, NULL);
+ /* the narrow algorithm will need access to the intersected candidate_datatype lists of all prev_il_instructions, as well as the
+ * list of the prev_il_instructions.
+ * Instead of creating two 'global' (within the class) variables, we create a single il_instruction_c variable (fake_prev_il_instruction),
+ * and shove that data into this single variable.
+ */
+ tmp_prev_il_instruction.prev_il_instruction = symbol->prev_il_instruction;
+ intersect_prev_candidate_datatype_lists(&tmp_prev_il_instruction);
+ /* Tell the il_instruction the datatype that it must generate - this was chosen by the next il_instruction (remember: we are iterating backwards!) */
+ fake_prev_il_instruction = &tmp_prev_il_instruction;
+ symbol->il_instruction->datatype = symbol->datatype;
+ symbol->il_instruction->accept(*this);
+ fake_prev_il_instruction = NULL;
+ }
+ return NULL;
+}
+
+
+
+
+// void *visit(instruction_list_c *symbol);
+void *narrow_candidate_datatypes_c::visit(il_simple_operation_c *symbol) {
+ /* Tell the il_simple_operator the datatype that it must generate - this was chosen by the next il_instruction (we iterate backwards!) */
+ symbol->il_simple_operator->datatype = symbol->datatype;
+ /* recursive call to see whether data types are compatible */
+ il_operand = symbol->il_operand;
+ symbol->il_simple_operator->accept(*this);
+ il_operand = NULL;
+ return NULL;
+}
+
+/* | function_name [il_operand_list] */
+/* NOTE: The parameters 'called_function_declaration' and 'extensible_param_count' are used to pass data between the stage 3 and stage 4. */
+// SYM_REF2(il_function_call_c, function_name, il_operand_list, symbol_c *called_function_declaration; int extensible_param_count;)
+void *narrow_candidate_datatypes_c::visit(il_function_call_c *symbol) {
+ /* The first parameter of a non formal function call in IL will be the 'current value' (i.e. the prev_il_instruction)
+ * In order to be able to handle this without coding special cases, we will simply prepend that symbol
+ * to the il_operand_list, and remove it after calling handle_function_call().
+ * However, since handle_function_call() will be recursively calling all parameter, and we don't want
+ * to do that for the prev_il_instruction (since it has already been visited by the fill_candidate_datatypes_c)
+ * we create a new ____ symbol_c ____ object, and copy the relevant info to/from that object before/after
+ * the call to handle_function_call().
+ *
+ * However, if no further paramters are given, then il_operand_list will be NULL, and we will
+ * need to create a new object to hold the pointer to prev_il_instruction.
+ * This change will also be undone at the end of this method.
+ */
+ symbol_c param_value = *fake_prev_il_instruction; /* copy the candidate_datatypes list */
+ if (NULL == symbol->il_operand_list) symbol->il_operand_list = new il_operand_list_c;
+ if (NULL == symbol->il_operand_list) ERROR;
+
+ ((list_c *)symbol->il_operand_list)->insert_element(¶m_value, 0);
+
+ generic_function_call_t fcall_param = {
+ /* fcall_param.function_name = */ symbol->function_name,
+ /* fcall_param.nonformal_operand_list = */ symbol->il_operand_list,
+ /* fcall_param.formal_operand_list = */ NULL,
+ /* enum {POU_FB, POU_function} POU_type = */ generic_function_call_t::POU_function,
+ /* fcall_param.candidate_functions = */ symbol->candidate_functions,
+ /* fcall_param.called_function_declaration = */ symbol->called_function_declaration,
+ /* fcall_param.extensible_param_count = */ symbol->extensible_param_count
+ };
+
+ narrow_function_invocation(symbol, fcall_param);
+ set_datatype_in_prev_il_instructions(param_value.datatype, fake_prev_il_instruction);
+
+ /* Undo the changes to the abstract syntax tree we made above... */
+ ((list_c *)symbol->il_operand_list)->remove_element(0);
+ if (((list_c *)symbol->il_operand_list)->n == 0) {
+ /* if the list becomes empty, then that means that it did not exist before we made these changes, so we delete it! */
+ delete symbol->il_operand_list;
+ symbol->il_operand_list = NULL;
+ }
+
+ return NULL;
+}
+
+
+/* | il_expr_operator '(' [il_operand] eol_list [simple_instr_list] ')' */
+// SYM_REF3(il_expression_c, il_expr_operator, il_operand, simple_instr_list);
+void *narrow_candidate_datatypes_c::visit(il_expression_c *symbol) {
+ /* first handle the operation (il_expr_operator) that will use the result coming from the parenthesised IL list (i.e. simple_instr_list) */
+ symbol->il_expr_operator->datatype = symbol->datatype;
+ il_operand = symbol->simple_instr_list; /* This is not a bug! The parenthesised expression will be used as the operator! */
+ symbol->il_expr_operator->accept(*this);
+
+ /* now give the parenthesised IL list a chance to narrow the datatypes */
+ /* The datatype that is must return was set by the call symbol->il_expr_operator->accept(*this) */
+ il_instruction_c *save_fake_prev_il_instruction = fake_prev_il_instruction; /*this is not really necessary, but lets play it safe */
+ symbol->simple_instr_list->accept(*this);
+ fake_prev_il_instruction = save_fake_prev_il_instruction;
+ return NULL;
+}
+
+
+
+
+/* il_jump_operator label */
+void *narrow_candidate_datatypes_c::visit(il_jump_operation_c *symbol) {
+ /* recursive call to fill the datatype */
+ symbol->il_jump_operator->datatype = symbol->datatype;
+ symbol->il_jump_operator->accept(*this);
+ return NULL;
+}
+
+
+
+
+
+
+
+/* il_call_operator prev_declared_fb_name
+ * | il_call_operator prev_declared_fb_name '(' ')'
+ * | il_call_operator prev_declared_fb_name '(' eol_list ')'
+ * | il_call_operator prev_declared_fb_name '(' il_operand_list ')'
+ * | il_call_operator prev_declared_fb_name '(' eol_list il_param_list ')'
+ */
+/* 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 */
+// SYM_REF4(il_fb_call_c, il_call_operator, fb_name, il_operand_list, il_param_list, symbol_c *called_fb_declaration)
+void *narrow_candidate_datatypes_c::visit(il_fb_call_c *symbol) {
+ symbol_c *fb_decl = symbol->called_fb_declaration;
+
+ /* Although a call to a non-declared FB is a semantic error, this is currently caught by stage 2! */
+ if (NULL == fb_decl) ERROR;
+ if (NULL != symbol->il_operand_list) narrow_nonformal_call(symbol, fb_decl);
+ if (NULL != symbol-> il_param_list) narrow_formal_call(symbol, fb_decl);
+
+ /* Let the il_call_operator (CAL, CALC, or CALCN) set the datatype of prev_il_instruction... */
+ symbol->il_call_operator->datatype = symbol->datatype;
+ symbol->il_call_operator->accept(*this);
+ return NULL;
+}
+
+
+/* | function_name '(' eol_list [il_param_list] ')' */
+/* NOTE: The parameter 'called_function_declaration' is used to pass data between the stage 3 and stage 4. */
+// SYM_REF2(il_formal_funct_call_c, function_name, il_param_list, symbol_c *called_function_declaration; int extensible_param_count;)
+void *narrow_candidate_datatypes_c::visit(il_formal_funct_call_c *symbol) {
+ generic_function_call_t fcall_param = {
+ /* fcall_param.function_name = */ symbol->function_name,
+ /* fcall_param.nonformal_operand_list = */ NULL,
+ /* fcall_param.formal_operand_list = */ symbol->il_param_list,
+ /* enum {POU_FB, POU_function} POU_type = */ generic_function_call_t::POU_function,
+ /* fcall_param.candidate_functions = */ symbol->candidate_functions,
+ /* fcall_param.called_function_declaration = */ symbol->called_function_declaration,
+ /* fcall_param.extensible_param_count = */ symbol->extensible_param_count
+ };
+
+ narrow_function_invocation(symbol, fcall_param);
+ /* The desired datatype of the previous il instruction was already set by narrow_function_invocation() */
+ return NULL;
+}
+
+
+// void *visit(il_operand_list_c *symbol);
+
+
+/* | simple_instr_list il_simple_instruction */
+/* This object is referenced by il_expression_c objects */
+void *narrow_candidate_datatypes_c::visit(simple_instr_list_c *symbol) {
+ if (symbol->n > 0)
+ symbol->elements[symbol->n - 1]->datatype = symbol->datatype;
+
+ for(int i = symbol->n-1; i >= 0; i--) {
+ symbol->elements[i]->accept(*this);
+ }
+ return NULL;
+}
+
+
+// SYM_REF1(il_simple_instruction_c, il_simple_instruction, symbol_c *prev_il_instruction;)
+void *narrow_candidate_datatypes_c::visit(il_simple_instruction_c *symbol) {
+ if (symbol->prev_il_instruction.size() > 1) ERROR; /* There should be no labeled insructions inside an IL expression! */
+
+ il_instruction_c tmp_prev_il_instruction(NULL, NULL);
+ /* the narrow algorithm will need access to the intersected candidate_datatype lists of all prev_il_instructions, as well as the
+ * list of the prev_il_instructions.
+ * Instead of creating two 'global' (within the class) variables, we create a single il_instruction_c variable (fake_prev_il_instruction),
+ * and shove that data into this single variable.
+ */
+ if (symbol->prev_il_instruction.size() > 0)
+ tmp_prev_il_instruction.candidate_datatypes = symbol->prev_il_instruction[0]->candidate_datatypes;
+ tmp_prev_il_instruction.prev_il_instruction = symbol->prev_il_instruction;
+
+ /* copy the candidate_datatypes list */
+ fake_prev_il_instruction = &tmp_prev_il_instruction;
+ symbol->il_simple_instruction->datatype = symbol->datatype;
+ symbol->il_simple_instruction->accept(*this);
+ fake_prev_il_instruction = NULL;
+ return NULL;
+}
+
+// void *visit(il_param_list_c *symbol);
+// void *visit(il_param_assignment_c *symbol);
+// void *visit(il_param_out_assignment_c *symbol);
+
+
+/*******************/
+/* B 2.2 Operators */
+/*******************/
+void *narrow_candidate_datatypes_c::narrow_binary_operator(const struct widen_entry widen_table[], symbol_c *symbol, bool *deprecated_operation) {
+ symbol_c *prev_instruction_type, *operand_type;
+ int count = 0;
+
+ if (NULL == symbol->datatype)
+ /* next IL instructions were unable to determine the datatype this instruction should produce */
+ return NULL;
+
+ if (NULL != deprecated_operation)
+ *deprecated_operation = false;
+
+ /* NOTE 1: the il_operand __may__ be pointing to a parenthesized list of IL instructions.
+ * e.g. LD 33
+ * AND ( 45
+ * OR 56
+ * )
+ * When we handle the first 'AND' IL_operator, the il_operand will point to an simple_instr_list_c.
+ * In this case, when we call il_operand->accept(*this);, the prev_il_instruction pointer will be overwritten!
+ *
+ * We must therefore set the prev_il_instruction->datatype = symbol->datatype;
+ * __before__ calling il_operand->accept(*this) !!
+ *
+ * NOTE 2: We do not need to call prev_il_instruction->accept(*this), as the object to which prev_il_instruction
+ * is pointing to will be later narrowed by the call from the for() loop of the instruction_list_c
+ * (or simple_instr_list_c), which iterates backwards.
+ */
+ for(unsigned int i = 0; i < fake_prev_il_instruction->candidate_datatypes.size(); i++) {
+ for(unsigned int j = 0; j < il_operand->candidate_datatypes.size(); j++) {
+ prev_instruction_type = fake_prev_il_instruction->candidate_datatypes[i];
+ operand_type = il_operand->candidate_datatypes[j];
+ if (is_widening_compatible(widen_table, prev_instruction_type, operand_type, symbol->datatype, deprecated_operation)) {
+ /* set the desired datatype of the previous il instruction */
+ set_datatype_in_prev_il_instructions(prev_instruction_type, fake_prev_il_instruction);
+ /* set the datatype for the operand */
+ il_operand->datatype = operand_type;
+
+ count ++;
+ }
+ }
+ }
+// if (count > 1) ERROR; /* Since we also support SAFE data types, this assertion is not necessarily always tru! */
+ if (is_type_valid(symbol->datatype) && (count <= 0)) ERROR;
+
+ il_operand->accept(*this);
+ return NULL;
+}
+
+
+
+
+
+void *narrow_candidate_datatypes_c::handle_il_instruction(symbol_c *symbol) {
+ if (NULL == symbol->datatype)
+ /* next IL instructions were unable to determine the datatype this instruction should produce */
+ return NULL;
+ /* NOTE 1: the il_operand __may__ be pointing to a parenthesized list of IL instructions.
+ * e.g. LD 33
+ * AND ( 45
+ * OR 56
+ * )
+ * When we handle the first 'AND' IL_operator, the il_operand will point to an simple_instr_list_c.
+ * In this case, when we call il_operand->accept(*this);, the prev_il_instruction pointer will be overwritten!
+ *
+ * We must therefore set the prev_il_instruction->datatype = symbol->datatype;
+ * __before__ calling il_operand->accept(*this) !!
+ *
+ * NOTE 2: We do not need to call prev_il_instruction->accept(*this), as the object to which prev_il_instruction
+ * is pointing to will be later narrowed by the call from the for() loop of the instruction_list_c
+ * (or simple_instr_list_c), which iterates backwards.
+ */
+ /* set the desired datatype of the previous il instruction */
+ set_datatype_in_prev_il_instructions(symbol->datatype, fake_prev_il_instruction);
+
+ /* set the datatype for the operand */
+ il_operand->datatype = symbol->datatype;
+ il_operand->accept(*this);
+ return NULL;
+}
+
+
+
+
+void *narrow_candidate_datatypes_c::visit(LD_operator_c *symbol) {
+ if (NULL == symbol->datatype)
+ /* next IL instructions were unable to determine the datatype this instruction should produce */
+ return NULL;
+ /* set the datatype for the operand */
+ il_operand->datatype = symbol->datatype;
+ il_operand->accept(*this);
+ return NULL;
+}
+
+
+void *narrow_candidate_datatypes_c::visit(LDN_operator_c *symbol) {
+ if (NULL == symbol->datatype)
+ /* next IL instructions were unable to determine the datatype this instruction should produce */
+ return NULL;
+ /* set the datatype for the operand */
+ il_operand->datatype = symbol->datatype;
+ il_operand->accept(*this);
+ return NULL;
+}
+
+void *narrow_candidate_datatypes_c::visit(ST_operator_c *symbol) {
+ if (symbol->candidate_datatypes.size() != 1)
+ return NULL;
+ symbol->datatype = symbol->candidate_datatypes[0];
+ /* set the datatype for the operand */
+ il_operand->datatype = symbol->datatype;
+ il_operand->accept(*this);
+ /* set the desired datatype of the previous il instruction */
+ set_datatype_in_prev_il_instructions(symbol->datatype, fake_prev_il_instruction);
+ return NULL;
+}
+
+void *narrow_candidate_datatypes_c::visit(STN_operator_c *symbol) {
+ if (symbol->candidate_datatypes.size() != 1)
+ return NULL;
+ symbol->datatype = symbol->candidate_datatypes[0];
+ /* set the datatype for the operand */
+ il_operand->datatype = symbol->datatype;
+ il_operand->accept(*this);
+ /* set the desired datatype of the previous il instruction */
+ set_datatype_in_prev_il_instructions(symbol->datatype, fake_prev_il_instruction);
+ return NULL;
+}
+
+void *narrow_candidate_datatypes_c::visit(NOT_operator_c *symbol) {
+ /* NOTE: the standard allows syntax in which the NOT operator is followed by an optional <il_operand>
+ * NOT [<il_operand>]
+ * However, it does not define the semantic of the NOT operation when the <il_operand> is specified.
+ * We therefore consider it an error if an il_operand is specified!
+ */
+ /* We do not change the data type, we simply invert the bits in bit types! */
+ /* So, we set the desired datatype of the previous il instruction */
+ set_datatype_in_prev_il_instructions(symbol->datatype, fake_prev_il_instruction);
+ return NULL;
+}
+
+void *narrow_candidate_datatypes_c::visit(S_operator_c *symbol) {
+ /* TODO: what if this is a FB call? */
+ return handle_il_instruction(symbol);
+}
+void *narrow_candidate_datatypes_c::visit(R_operator_c *symbol) {
+ /* TODO: what if this is a FB call? */
+ return handle_il_instruction(symbol);
+}
+
+
+void *narrow_candidate_datatypes_c::visit( S1_operator_c *symbol) {return narrow_implicit_il_fb_call(symbol, "S1", symbol->called_fb_declaration);}
+void *narrow_candidate_datatypes_c::visit( R1_operator_c *symbol) {return narrow_implicit_il_fb_call(symbol, "R1", symbol->called_fb_declaration);}
+void *narrow_candidate_datatypes_c::visit( CLK_operator_c *symbol) {return narrow_implicit_il_fb_call(symbol, "CLK", symbol->called_fb_declaration);}
+void *narrow_candidate_datatypes_c::visit( CU_operator_c *symbol) {return narrow_implicit_il_fb_call(symbol, "CU", symbol->called_fb_declaration);}
+void *narrow_candidate_datatypes_c::visit( CD_operator_c *symbol) {return narrow_implicit_il_fb_call(symbol, "CD", symbol->called_fb_declaration);}
+void *narrow_candidate_datatypes_c::visit( PV_operator_c *symbol) {return narrow_implicit_il_fb_call(symbol, "PV", symbol->called_fb_declaration);}
+void *narrow_candidate_datatypes_c::visit( IN_operator_c *symbol) {return narrow_implicit_il_fb_call(symbol, "IN", symbol->called_fb_declaration);}
+void *narrow_candidate_datatypes_c::visit( PT_operator_c *symbol) {return narrow_implicit_il_fb_call(symbol, "PT", symbol->called_fb_declaration);}
+
+void *narrow_candidate_datatypes_c::visit( AND_operator_c *symbol) {return narrow_binary_operator(widen_AND_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( OR_operator_c *symbol) {return narrow_binary_operator( widen_OR_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( XOR_operator_c *symbol) {return narrow_binary_operator(widen_XOR_table, symbol);}
+void *narrow_candidate_datatypes_c::visit(ANDN_operator_c *symbol) {return narrow_binary_operator(widen_AND_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( ORN_operator_c *symbol) {return narrow_binary_operator( widen_OR_table, symbol);}
+void *narrow_candidate_datatypes_c::visit(XORN_operator_c *symbol) {return narrow_binary_operator(widen_XOR_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( ADD_operator_c *symbol) {return narrow_binary_operator(widen_ADD_table, symbol, &(symbol->deprecated_operation));}
+void *narrow_candidate_datatypes_c::visit( SUB_operator_c *symbol) {return narrow_binary_operator(widen_SUB_table, symbol, &(symbol->deprecated_operation));}
+void *narrow_candidate_datatypes_c::visit( MUL_operator_c *symbol) {return narrow_binary_operator(widen_MUL_table, symbol, &(symbol->deprecated_operation));}
+void *narrow_candidate_datatypes_c::visit( DIV_operator_c *symbol) {return narrow_binary_operator(widen_DIV_table, symbol, &(symbol->deprecated_operation));}
+void *narrow_candidate_datatypes_c::visit( MOD_operator_c *symbol) {return narrow_binary_operator(widen_MOD_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( GT_operator_c *symbol) {return narrow_binary_operator(widen_CMP_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( GE_operator_c *symbol) {return narrow_binary_operator(widen_CMP_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( EQ_operator_c *symbol) {return narrow_binary_operator(widen_CMP_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( LT_operator_c *symbol) {return narrow_binary_operator(widen_CMP_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( LE_operator_c *symbol) {return narrow_binary_operator(widen_CMP_table, symbol);}
+void *narrow_candidate_datatypes_c::visit( NE_operator_c *symbol) {return narrow_binary_operator(widen_CMP_table, symbol);}
+
+
+
+
+void *narrow_candidate_datatypes_c::narrow_conditional_flow_control_IL_instruction(symbol_c *symbol) {
+ /* if the next IL instructions needs us to provide a datatype other than a bool,
+ * then we have an internal compiler error - most likely in fill_candidate_datatypes_c
+ */
+ if ((NULL != symbol->datatype) && (!is_ANY_BOOL_compatible(symbol->datatype))) ERROR;
+ if (symbol->candidate_datatypes.size() > 1) ERROR;
+
+ /* NOTE: If there is no IL instruction following this CALC, CALCN, JMPC, JMPC, ..., instruction,
+ * we must still provide a bool_type_name_c datatype (if possible, i.e. if it exists in the candidate datatype list).
+ * If it is not possible, we set it to NULL
+ */
+ if (symbol->candidate_datatypes.size() == 0) symbol->datatype = NULL;
+ else symbol->datatype = symbol->candidate_datatypes[0]; /* i.e. a bool_type_name_c! */
+ if ((NULL != symbol->datatype) && (!is_ANY_BOOL_compatible(symbol->datatype))) ERROR;
+
+ /* set the required datatype of the previous IL instruction, i.e. a bool_type_name_c! */
+ set_datatype_in_prev_il_instructions(symbol->datatype, fake_prev_il_instruction);
+ return NULL;
+}
+
+
+// SYM_REF0(CAL_operator_c)
+// SYM_REF0(CALC_operator_c)
+// SYM_REF0(CALCN_operator_c)
+/* called from visit(il_fb_call_c *) {symbol->il_call_operator->accpet(*this)} */
+/* NOTE: The CAL, JMP and RET instructions simply set the desired datatype of the previous il instruction since they do not change the value in the current/default IL variable */
+/* called from il_fb_call_c (symbol->il_call_operator->accpet(*this) ) */
+void *narrow_candidate_datatypes_c::visit( CAL_operator_c *symbol) {set_datatype_in_prev_il_instructions(symbol->datatype, fake_prev_il_instruction); return NULL;}
+void *narrow_candidate_datatypes_c::visit( RET_operator_c *symbol) {set_datatype_in_prev_il_instructions(symbol->datatype, fake_prev_il_instruction); return NULL;}
+void *narrow_candidate_datatypes_c::visit( JMP_operator_c *symbol) {set_datatype_in_prev_il_instructions(symbol->datatype, fake_prev_il_instruction); return NULL;}
+void *narrow_candidate_datatypes_c::visit( CALC_operator_c *symbol) {return narrow_conditional_flow_control_IL_instruction(symbol);}
+void *narrow_candidate_datatypes_c::visit(CALCN_operator_c *symbol) {return narrow_conditional_flow_control_IL_instruction(symbol);}
+void *narrow_candidate_datatypes_c::visit( RETC_operator_c *symbol) {return narrow_conditional_flow_control_IL_instruction(symbol);}
+void *narrow_candidate_datatypes_c::visit(RETCN_operator_c *symbol) {return narrow_conditional_flow_control_IL_instruction(symbol);}
+void *narrow_candidate_datatypes_c::visit( JMPC_operator_c *symbol) {return narrow_conditional_flow_control_IL_instruction(symbol);}
+void *narrow_candidate_datatypes_c::visit(JMPCN_operator_c *symbol) {return narrow_conditional_flow_control_IL_instruction(symbol);}
+
+/* Symbol class handled together with function call checks */
+// void *visit(il_assign_operator_c *symbol, variable_name);
+/* Symbol class handled together with function call checks */
+// void *visit(il_assign_operator_c *symbol, option, variable_name);
+
+
+/***************************************/
+/* B.3 - Language ST (Structured Text) */
+/***************************************/
+/***********************/
+/* B 3.1 - Expressions */
+/***********************/
+void *narrow_candidate_datatypes_c::narrow_binary_expression(const struct widen_entry widen_table[], symbol_c *symbol, symbol_c *l_expr, symbol_c *r_expr, bool *deprecated_operation) {
+ symbol_c *l_type, *r_type;
+ int count = 0;
+
+ if (NULL != deprecated_operation)
+ *deprecated_operation = false;
+
+ for(unsigned int i = 0; i < l_expr->candidate_datatypes.size(); i++) {
+ for(unsigned int j = 0; j < r_expr->candidate_datatypes.size(); j++) {
+ /* test widening compatibility */
+ l_type = l_expr->candidate_datatypes[i];
+ r_type = r_expr->candidate_datatypes[j];
+ if (is_widening_compatible(widen_table, l_type, r_type, symbol->datatype, deprecated_operation)) {
+ l_expr->datatype = l_type;
+ r_expr->datatype = r_type;
+ count ++;
+ }
+ }
+ }
+// if (count > 1) ERROR; /* Since we also support SAFE data types, this assertion is not necessarily always tru! */
+ if (is_type_valid(symbol->datatype) && (count <= 0)) ERROR;
+
+ l_expr->accept(*this);
+ r_expr->accept(*this);
+ return NULL;
+}
+
+
+
+void *narrow_candidate_datatypes_c::visit( or_expression_c *symbol) {return narrow_binary_expression( widen_OR_table, symbol, symbol->l_exp, symbol->r_exp);}
+void *narrow_candidate_datatypes_c::visit( xor_expression_c *symbol) {return narrow_binary_expression(widen_XOR_table, symbol, symbol->l_exp, symbol->r_exp);}
+void *narrow_candidate_datatypes_c::visit( and_expression_c *symbol) {return narrow_binary_expression(widen_AND_table, symbol, symbol->l_exp, symbol->r_exp);}
+
+void *narrow_candidate_datatypes_c::visit( equ_expression_c *symbol) {return narrow_binary_expression(widen_CMP_table, symbol, symbol->l_exp, symbol->r_exp);}
+void *narrow_candidate_datatypes_c::visit(notequ_expression_c *symbol) {return narrow_binary_expression(widen_CMP_table, symbol, symbol->l_exp, symbol->r_exp);}
+void *narrow_candidate_datatypes_c::visit( lt_expression_c *symbol) {return narrow_binary_expression(widen_CMP_table, symbol, symbol->l_exp, symbol->r_exp);}
+void *narrow_candidate_datatypes_c::visit( gt_expression_c *symbol) {return narrow_binary_expression(widen_CMP_table, symbol, symbol->l_exp, symbol->r_exp);}
+void *narrow_candidate_datatypes_c::visit( le_expression_c *symbol) {return narrow_binary_expression(widen_CMP_table, symbol, symbol->l_exp, symbol->r_exp);}
+void *narrow_candidate_datatypes_c::visit( ge_expression_c *symbol) {return narrow_binary_expression(widen_CMP_table, symbol, symbol->l_exp, symbol->r_exp);}
+
+void *narrow_candidate_datatypes_c::visit( add_expression_c *symbol) {return narrow_binary_expression(widen_ADD_table, symbol, symbol->l_exp, symbol->r_exp, &symbol->deprecated_operation);}
+void *narrow_candidate_datatypes_c::visit( sub_expression_c *symbol) {return narrow_binary_expression(widen_SUB_table, symbol, symbol->l_exp, symbol->r_exp, &symbol->deprecated_operation);}
+void *narrow_candidate_datatypes_c::visit( mul_expression_c *symbol) {return narrow_binary_expression(widen_MUL_table, symbol, symbol->l_exp, symbol->r_exp, &symbol->deprecated_operation);}
+void *narrow_candidate_datatypes_c::visit( div_expression_c *symbol) {return narrow_binary_expression(widen_DIV_table, symbol, symbol->l_exp, symbol->r_exp, &symbol->deprecated_operation);}
+void *narrow_candidate_datatypes_c::visit( mod_expression_c *symbol) {return narrow_binary_expression(widen_MOD_table, symbol, symbol->l_exp, symbol->r_exp);}
+void *narrow_candidate_datatypes_c::visit( power_expression_c *symbol) {return narrow_binary_expression(widen_EXPT_table,symbol, symbol->l_exp, symbol->r_exp);}
+
+
+void *narrow_candidate_datatypes_c::visit(neg_expression_c *symbol) {
+ symbol->exp->datatype = symbol->datatype;
+ symbol->exp->accept(*this);
+ return NULL;
+}
+
+
+void *narrow_candidate_datatypes_c::visit(not_expression_c *symbol) {
+ symbol->exp->datatype = symbol->datatype;
+ symbol->exp->accept(*this);
+ return NULL;
+}
+
+
+
+/* NOTE: The parameter 'called_function_declaration', 'extensible_param_count' and 'candidate_functions' are used to pass data between the stage 3 and stage 4. */
+/* formal_param_list -> may be NULL ! */
+/* nonformal_param_list -> may be NULL ! */
+// SYM_REF3(function_invocation_c, function_name, formal_param_list, nonformal_param_list, symbol_c *called_function_declaration; int extensible_param_count; std::vector <symbol_c *> candidate_functions;)
+void *narrow_candidate_datatypes_c::visit(function_invocation_c *symbol) {
+ generic_function_call_t fcall_param = {
+ /* fcall_param.function_name = */ symbol->function_name,
+ /* fcall_param.nonformal_operand_list = */ symbol->nonformal_param_list,
+ /* fcall_param.formal_operand_list = */ symbol->formal_param_list,
+ /* enum {POU_FB, POU_function} POU_type = */ generic_function_call_t::POU_function,
+ /* fcall_param.candidate_functions = */ symbol->candidate_functions,
+ /* fcall_param.called_function_declaration = */ symbol->called_function_declaration,
+ /* fcall_param.extensible_param_count = */ symbol->extensible_param_count
+ };
+
+ narrow_function_invocation(symbol, fcall_param);
+ return NULL;
+}
+
+/********************/
+/* B 3.2 Statements */
+/********************/
+
+
+/*********************************/
+/* B 3.2.1 Assignment Statements */
+/*********************************/
+
+void *narrow_candidate_datatypes_c::visit(assignment_statement_c *symbol) {
+ if (symbol->candidate_datatypes.size() != 1)
+ return NULL;
+ symbol->datatype = symbol->candidate_datatypes[0];
+ symbol->l_exp->datatype = symbol->datatype;
+ symbol->l_exp->accept(*this);
+ symbol->r_exp->datatype = symbol->datatype;
+ symbol->r_exp->accept(*this);
+ return NULL;
+}
+
+
+/*****************************************/
+/* B 3.2.2 Subprogram Control Statements */
+/*****************************************/
+
+void *narrow_candidate_datatypes_c::visit(fb_invocation_c *symbol) {
+ /* Note: We do not use the symbol->called_fb_declaration value (set in fill_candidate_datatypes_c)
+ * because we try to identify any other datatype errors in the expressions used in the
+ * parameters to the FB call (e.g. fb_var(var1 * 56 + func(var * 43)) )
+ * even it the call to the FB is invalid.
+ * This makes sense because it may be errors in those expressions which are
+ * making this an invalid call, so it makes sense to point them out to the user!
+ */
+ symbol_c *fb_decl = search_varfb_instance_type->get_basetype_decl(symbol->fb_name);
+
+ /* Although a call to a non-declared FB is a semantic error, this is currently caught by stage 2! */
+ if (NULL == fb_decl) ERROR;
+ if (NULL != symbol->nonformal_param_list) narrow_nonformal_call(symbol, fb_decl);
+ if (NULL != symbol-> formal_param_list) narrow_formal_call(symbol, fb_decl);
+
+ return NULL;
+}
+
+
+/********************************/
+/* B 3.2.3 Selection Statements */
+/********************************/
+
+void *narrow_candidate_datatypes_c::visit(if_statement_c *symbol) {
+ for(unsigned int i = 0; i < symbol->expression->candidate_datatypes.size(); i++) {
+ if (is_ANY_BOOL_compatible(symbol->expression->candidate_datatypes[i]))
+ symbol->expression->datatype = symbol->expression->candidate_datatypes[i];
+ }
+ symbol->expression->accept(*this);
+ if (NULL != symbol->statement_list)
+ symbol->statement_list->accept(*this);
+ if (NULL != symbol->elseif_statement_list)
+ symbol->elseif_statement_list->accept(*this);
+ if (NULL != symbol->else_statement_list)
+ symbol->else_statement_list->accept(*this);
+ return NULL;
+}
+
+
+void *narrow_candidate_datatypes_c::visit(elseif_statement_c *symbol) {
+ for (unsigned int i = 0; i < symbol->expression->candidate_datatypes.size(); i++) {
+ if (is_ANY_BOOL_compatible(symbol->expression->candidate_datatypes[i]))
+ symbol->expression->datatype = symbol->expression->candidate_datatypes[i];
+ }
+ symbol->expression->accept(*this);
+ if (NULL != symbol->statement_list)
+ symbol->statement_list->accept(*this);
+ return NULL;
+}
+
+/* CASE expression OF case_element_list ELSE statement_list END_CASE */
+// SYM_REF3(case_statement_c, expression, case_element_list, statement_list)
+void *narrow_candidate_datatypes_c::visit(case_statement_c *symbol) {
+ for (unsigned int i = 0; i < symbol->expression->candidate_datatypes.size(); i++) {
+ if ((is_ANY_INT_type(symbol->expression->candidate_datatypes[i]))
+ || (search_base_type.type_is_enumerated(symbol->expression->candidate_datatypes[i])))
+ symbol->expression->datatype = symbol->expression->candidate_datatypes[i];
+ }
+ symbol->expression->accept(*this);
+ if (NULL != symbol->statement_list)
+ symbol->statement_list->accept(*this);
+ if (NULL != symbol->case_element_list) {
+ symbol->case_element_list->datatype = symbol->expression->datatype;
+ symbol->case_element_list->accept(*this);
+ }
+ return NULL;
+}
+
+/* helper symbol for case_statement */
+// SYM_LIST(case_element_list_c)
+void *narrow_candidate_datatypes_c::visit(case_element_list_c *symbol) {
+ for (int i = 0; i < symbol->n; i++) {
+ symbol->elements[i]->datatype = symbol->datatype;
+ symbol->elements[i]->accept(*this);
+ }
+ return NULL;
+}
+
+/* case_list ':' statement_list */
+// SYM_REF2(case_element_c, case_list, statement_list)
+void *narrow_candidate_datatypes_c::visit(case_element_c *symbol) {
+ symbol->case_list->datatype = symbol->datatype;
+ symbol->case_list->accept(*this);
+ symbol->statement_list->accept(*this);
+ return NULL;
+}
+
+// SYM_LIST(case_list_c)
+void *narrow_candidate_datatypes_c::visit(case_list_c *symbol) {
+ for (int i = 0; i < symbol->n; i++) {
+ for (unsigned int k = 0; k < symbol->elements[i]->candidate_datatypes.size(); k++) {
+ if (is_type_equal(symbol->datatype, symbol->elements[i]->candidate_datatypes[k]))
+ symbol->elements[i]->datatype = symbol->elements[i]->candidate_datatypes[k];
+ }
+ /* NOTE: this may be an integer, a subrange_c, or a enumerated value! */
+ symbol->elements[i]->accept(*this);
+ }
+ return NULL;
+}
+
+
+/********************************/
+/* B 3.2.4 Iteration Statements */
+/********************************/
+void *narrow_candidate_datatypes_c::visit(for_statement_c *symbol) {
+ /* Control variable */
+ for(unsigned int i = 0; i < symbol->control_variable->candidate_datatypes.size(); i++) {
+ if (is_ANY_INT_type(symbol->control_variable->candidate_datatypes[i])) {
+ symbol->control_variable->datatype = symbol->control_variable->candidate_datatypes[i];
+ }
+ }
+ symbol->control_variable->accept(*this);
+ /* BEG expression */
+ for(unsigned int i = 0; i < symbol->beg_expression->candidate_datatypes.size(); i++) {
+ if (is_type_equal(symbol->control_variable->datatype,symbol->beg_expression->candidate_datatypes[i]) &&
+ is_ANY_INT_type(symbol->beg_expression->candidate_datatypes[i])) {
+ symbol->beg_expression->datatype = symbol->beg_expression->candidate_datatypes[i];
+ }
+ }
+ symbol->beg_expression->accept(*this);
+ /* END expression */
+ for(unsigned int i = 0; i < symbol->end_expression->candidate_datatypes.size(); i++) {
+ if (is_type_equal(symbol->control_variable->datatype,symbol->end_expression->candidate_datatypes[i]) &&
+ is_ANY_INT_type(symbol->end_expression->candidate_datatypes[i])) {
+ symbol->end_expression->datatype = symbol->end_expression->candidate_datatypes[i];
+ }
+ }
+ symbol->end_expression->accept(*this);
+ /* BY expression */
+ if (NULL != symbol->by_expression) {
+ for(unsigned int i = 0; i < symbol->by_expression->candidate_datatypes.size(); i++) {
+ if (is_type_equal(symbol->control_variable->datatype,symbol->by_expression->candidate_datatypes[i]) &&
+ is_ANY_INT_type(symbol->by_expression->candidate_datatypes[i])) {
+ symbol->by_expression->datatype = symbol->by_expression->candidate_datatypes[i];
+ }
+ }
+ symbol->by_expression->accept(*this);
+ }
+ if (NULL != symbol->statement_list)
+ symbol->statement_list->accept(*this);
+ return NULL;
+}
+
+void *narrow_candidate_datatypes_c::visit(while_statement_c *symbol) {
+ for (unsigned int i = 0; i < symbol->expression->candidate_datatypes.size(); i++) {
+ if(is_BOOL_type(symbol->expression->candidate_datatypes[i]))
+ symbol->expression->datatype = symbol->expression->candidate_datatypes[i];
+ }
+ symbol->expression->accept(*this);
+ if (NULL != symbol->statement_list)
+ symbol->statement_list->accept(*this);
+ return NULL;
+}
+
+void *narrow_candidate_datatypes_c::visit(repeat_statement_c *symbol) {
+ for (unsigned int i = 0; i < symbol->expression->candidate_datatypes.size(); i++) {
+ if(is_BOOL_type(symbol->expression->candidate_datatypes[i]))
+ symbol->expression->datatype = symbol->expression->candidate_datatypes[i];
+ }
+ symbol->expression->accept(*this);
+ if (NULL != symbol->statement_list)
+ symbol->statement_list->accept(*this);
+ return NULL;
+}
+
+
+
+
+