--- a/stage3/fill_candidate_datatypes.cc Mon Mar 11 12:54:25 2013 +0100
+++ b/stage3/fill_candidate_datatypes.cc Thu Apr 04 09:45:11 2013 +0900
@@ -798,6 +798,69 @@
/********************************/
/* B 1.3.3 - Derived data types */
/********************************/
+
+void *fill_candidate_datatypes_c::fill_type_decl(symbol_c *symbol, symbol_c *type_name, symbol_c *spec_init) {
+ /* NOTE: Unlike the rest of the 'fill' algorithm that works using a bottom->up approach, when handling
+ * data type declarations (section B.1.3.3 - Derived data types) we use a top->bottom approach.
+ * This is intentional, and not a bug! Explanation follows...
+ * Here we are essentially determining the base type of each defined data type. In many cases (especially structs,
+ * enumerations, arrays, etc...), the datatype is its own base type. However, the derived datatype is stored in
+ * multiple symbol_c classes (e.g. an enumeration uses enumerated_type_declaration_c, enumerated_spec_init_c,
+ * enumerated_value_list_c, enumerated_value_c, ...). Several of these could be chosen to work as the canonical base datatype
+ * symbol. Which symbol is used is really up to the search_base_type_c, and not this fill_candidate_datatypes_c.
+ * Here we must right the code to handle whatever the search_base_type_c chooses to use as the canonical symbol to represent
+ * the base datatype.
+ * Since the base datatype may be (and sometimes/often/always(?) actually is) the top level symbol_c (an enumerated_type_declaration_c
+ * in the case of the enumerations), it only makes sense to ask search_base_type_c for a basetype when we pass it the
+ * symbol in the highest level of the type declaration (the enumerated_type_declaration_c in the case of the enumerations).
+ * For this reason, we determine the basetype at the top level, and send that info down to the bottom level of the data type
+ * declaration. In summary, a top->down algorithm!
+ */
+ add_datatype_to_candidate_list(symbol, base_type(symbol));
+ type_name->candidate_datatypes = symbol->candidate_datatypes; // use top->down algorithm!!
+ spec_init->candidate_datatypes = symbol->candidate_datatypes; // use top->down algorithm!!
+ spec_init->accept(*this);
+ return NULL;
+}
+
+
+void *fill_candidate_datatypes_c::fill_spec_init(symbol_c *symbol, symbol_c *type_spec, symbol_c *init_value) {
+ /* NOTE: The note in the fill_type_decl() function is also partially valid here,
+ * i.e. here too we work using a top->down algorithm for the type_spec part, but a bottom->up algorithm
+ * for the init_value part!!
+ */
+ /* NOTE: When a variable is declared inside a POU as, for example
+ * VAR
+ * a : ARRAY[9] OF REAL;
+ * e : ENUM (black, white, gray);
+ * s : STRUCT x, y: REAL; END_STRUCT
+ * END_VAR
+ * the anonymous datatype will be defined directly by the ***_spec_init_c, and will not have an
+ * ****_type_declaration_c. In these cases, the anonymous data type is its own basetype, and the
+ * ***_spec_init_c class will act as the canonical symbol that represents the (anonymous) basetype.
+ *
+ * This method must handle the above case, as well as the case in which the ***_spec_init_c is called
+ * from an ****_type_declaration_c.
+ */
+ if (symbol->candidate_datatypes.size() == 0) // i.e., if this is an anonymous datatype!
+ add_datatype_to_candidate_list(symbol, base_type(symbol));
+
+ // use top->down algorithm!!
+ type_spec->candidate_datatypes = symbol->candidate_datatypes;
+ type_spec->accept(*this);
+
+ // use bottom->up algorithm!!
+ if (NULL != init_value) init_value->accept(*this);
+ /* NOTE: Even if the constant and the type are of incompatible data types, we let the
+ * ***_spec_init_c object inherit the data type of the type declaration (simple_specification)
+ * This will let us produce more informative error messages when checking data type compatibility
+ * with located variables (AT %QW3.4 : WORD).
+ */
+ // if (NULL != init_value) intersect_candidate_datatype_list(symbol /*origin, dest.*/, init_value /*with*/);
+ return NULL;
+}
+
+
/* TYPE type_declaration_list END_TYPE */
// SYM_REF1(data_type_declaration_c, type_declaration_list)
/* NOTE: Not required. already handled by iterator_visitor_c base class */
@@ -808,32 +871,25 @@
/* simple_type_name ':' simple_spec_init */
// SYM_REF2(simple_type_declaration_c, simple_type_name, simple_spec_init)
-/* NOTE: Not required. already handled by iterator_visitor_c base class */
+void *fill_candidate_datatypes_c::visit(simple_type_declaration_c *symbol) {return fill_type_decl(symbol, symbol->simple_type_name, symbol->simple_spec_init);}
+
/* simple_specification ASSIGN constant */
// SYM_REF2(simple_spec_init_c, simple_specification, constant)
-void *fill_candidate_datatypes_c::visit(simple_spec_init_c *symbol) {
- if (NULL != symbol->constant) symbol->constant->accept(*this);
- add_datatype_to_candidate_list(symbol->simple_specification, base_type(symbol->simple_specification));
- symbol->candidate_datatypes = symbol->simple_specification->candidate_datatypes;
- /* NOTE: Even if the constant and the type are of incompatible data types, we let the
- * simple_spec_init_c object inherit the data type of the type declaration (simple_specification)
- * This will let us produce more informative error messages when checking data type compatibility
- * with located variables (AT %QW3.4 : WORD).
- */
- // if (NULL != symbol->constant) intersect_candidate_datatype_list(symbol /*origin, dest.*/, symbol->constant /*with*/);
- return NULL;
-}
+void *fill_candidate_datatypes_c::visit(simple_spec_init_c *symbol) {return fill_spec_init(symbol, symbol->simple_specification, symbol->constant);}
/* subrange_type_name ':' subrange_spec_init */
// SYM_REF2(subrange_type_declaration_c, subrange_type_name, subrange_spec_init)
+void *fill_candidate_datatypes_c::visit(subrange_type_declaration_c *symbol) {return fill_type_decl(symbol, symbol->subrange_type_name, symbol->subrange_spec_init);}
/* subrange_specification ASSIGN signed_integer */
// SYM_REF2(subrange_spec_init_c, subrange_specification, signed_integer)
+void *fill_candidate_datatypes_c::visit(subrange_spec_init_c *symbol) {return fill_spec_init(symbol, symbol->subrange_specification, symbol->signed_integer);}
/* integer_type_name '(' subrange')' */
// SYM_REF2(subrange_specification_c, integer_type_name, subrange)
+// NOTE: not needed! Iterator visitor already handles this!
/* signed_integer DOTDOT signed_integer */
/* dimension will be filled in during stage 3 (array_range_check_c) with the number of elements in this subrange */
@@ -854,41 +910,25 @@
/* enumerated_type_name ':' enumerated_spec_init */
// SYM_REF2(enumerated_type_declaration_c, enumerated_type_name, enumerated_spec_init)
-void *fill_candidate_datatypes_c::visit(enumerated_type_declaration_c *symbol) {
- current_enumerated_spec_type = base_type(symbol);
- add_datatype_to_candidate_list(symbol, current_enumerated_spec_type);
- add_datatype_to_candidate_list(symbol->enumerated_type_name, current_enumerated_spec_type);
- symbol->enumerated_spec_init->accept(*this);
- current_enumerated_spec_type = NULL;
- return NULL;
-}
+void *fill_candidate_datatypes_c::visit(enumerated_type_declaration_c *symbol) {return fill_type_decl(symbol, symbol->enumerated_type_name, symbol->enumerated_spec_init);}
/* enumerated_specification ASSIGN enumerated_value */
// SYM_REF2(enumerated_spec_init_c, enumerated_specification, enumerated_value)
-void *fill_candidate_datatypes_c::visit(enumerated_spec_init_c *symbol) {
- /* If we are handling an anonymous datatype (i.e. a datatype implicitly declared inside a VAR ... END_VAR declaration)
- * then the symbol->datatype has not yet been set by the previous visit(enumerated_spec_init_c) method!
- */
- if (NULL == current_enumerated_spec_type)
- current_enumerated_spec_type = base_type(symbol);
- add_datatype_to_candidate_list(symbol, current_enumerated_spec_type);
- symbol->enumerated_specification->accept(*this); /* calls enumerated_value_list_c (or identifier_c, which we ignore!) visit method */
- current_enumerated_spec_type = NULL;
- if (NULL != symbol->enumerated_value) symbol->enumerated_value->accept(*this);
- return NULL;
-}
+// NOTE: enumerated_specification is either an enumerated_value_list_c or identifier_c.
+void *fill_candidate_datatypes_c::visit(enumerated_spec_init_c *symbol) {return fill_spec_init(symbol, symbol->enumerated_specification, symbol->enumerated_value);}
+
/* helper symbol for enumerated_specification->enumerated_spec_init */
/* enumerated_value_list ',' enumerated_value */
// SYM_LIST(enumerated_value_list_c)
void *fill_candidate_datatypes_c::visit(enumerated_value_list_c *symbol) {
- if (NULL == current_enumerated_spec_type) ERROR;
- add_datatype_to_candidate_list(symbol, current_enumerated_spec_type);
+ if (symbol->candidate_datatypes.size() != 1) ERROR;
+ symbol_c *current_enumerated_spec_type = symbol->candidate_datatypes[0];
/* We already know the datatype of the enumerated_value(s) in the list, so we set them directly instead of recursively calling the enumerated_value_c visit method! */
for(int i = 0; i < symbol->n; i++)
- add_datatype_to_candidate_list(symbol->elements[i], current_enumerated_spec_type);
+ add_datatype_to_candidate_list(symbol->elements[i], current_enumerated_spec_type); // top->down algorithm!!
return NULL;
}
@@ -969,10 +1009,12 @@
/* identifier ':' array_spec_init */
// SYM_REF2(array_type_declaration_c, identifier, array_spec_init)
+void *fill_candidate_datatypes_c::visit(array_type_declaration_c *symbol) {return fill_type_decl(symbol, symbol->identifier, symbol->array_spec_init);}
/* array_specification [ASSIGN array_initialization} */
/* array_initialization may be NULL ! */
// SYM_REF2(array_spec_init_c, array_specification, array_initialization)
+void *fill_candidate_datatypes_c::visit(array_spec_init_c *symbol) {return fill_spec_init(symbol, symbol->array_specification, symbol->array_initialization);}
/* ARRAY '[' array_subrange_list ']' OF non_generic_type_name */
// SYM_REF2(array_specification_c, array_subrange_list, non_generic_type_name)
@@ -992,10 +1034,12 @@
/* structure_type_name ':' structure_specification */
// SYM_REF2(structure_type_declaration_c, structure_type_name, structure_specification)
+void *fill_candidate_datatypes_c::visit(structure_type_declaration_c *symbol) {return fill_type_decl(symbol, symbol->structure_type_name, symbol->structure_specification);}
/* structure_type_name ASSIGN structure_initialization */
/* structure_initialization may be NULL ! */
// SYM_REF2(initialized_structure_c, structure_type_name, structure_initialization)
+void *fill_candidate_datatypes_c::visit(initialized_structure_c *symbol) {return fill_spec_init(symbol, symbol->structure_type_name, symbol->structure_initialization);}
/* helper symbol for structure_declaration */
/* structure_declaration: STRUCT structure_element_declaration_list END_STRUCT */
@@ -1017,6 +1061,11 @@
// SYM_REF4(string_type_declaration_c, string_type_name, elementary_string_type_name, string_type_declaration_size, string_type_declaration_init/* may be == NULL! */)
+/* function_block_type_name ASSIGN structure_initialization */
+/* structure_initialization -> may be NULL ! */
+// SYM_REF2(fb_spec_init_c, function_block_type_name, structure_initialization)
+void *fill_candidate_datatypes_c::visit(fb_spec_init_c *symbol) {return fill_spec_init(symbol, symbol->function_block_type_name, symbol->structure_initialization);}
+
/*********************/
@@ -1211,8 +1260,6 @@
-
-
/************************************/
/* B 1.5 Program organization units */
/************************************/
@@ -1249,6 +1296,12 @@
search_varfb_instance_type = NULL;
local_enumerated_value_symtable.reset();
+
+ /* The FB declaration itself may be used as a dataype! We now do the fill algorithm considering
+ * function_block_declaration_c a data type declaration...
+ */
+ // The next line is essentially equivalent to doing--> symbol->candidate_datatypes.push_back(symbol);
+ add_datatype_to_candidate_list(symbol, base_type(symbol));
return NULL;
}