--- a/absyntax_utils/search_varfb_instance_type.cc Wed Sep 07 19:28:10 2011 +0200
+++ b/absyntax_utils/search_varfb_instance_type.cc Thu Sep 08 20:25:00 2011 +0200
@@ -94,12 +94,14 @@
search_varfb_instance_type_c::search_varfb_instance_type_c(symbol_c *search_scope): search_var_instance_decl(search_scope) {
this->decompose_var_instance_name = NULL;
this->current_structelement_name = NULL;
- this->current_rawtype = NULL;
-}
-
-symbol_c *search_varfb_instance_type_c::get_basetype_decl(symbol_c *variable_name) {
+ this->current_typeid = NULL;
+ this->current_basetypeid = NULL;
+}
+
+symbol_c *search_varfb_instance_type_c::get_type_decl(symbol_c *variable_name) {
this->current_structelement_name = NULL;
- this->current_rawtype = NULL;
+ this->current_typeid = NULL;
+ this->current_basetypeid = NULL;
this->decompose_var_instance_name = new decompose_var_instance_name_c(variable_name);
if (NULL == decompose_var_instance_name) ERROR;
@@ -112,10 +114,7 @@
/* Now we try to find the variable instance declaration, to determine its type... */
symbol_c *var_decl = search_var_instance_decl.get_decl(var_name_part);
- if (NULL == var_decl) {
- /* variable instance declaration not found! */
- ERROR;
- }
+ if (NULL == var_decl) ERROR;
/* if it is a struct or function block, we must search the type
* of the struct or function block member.
@@ -124,18 +123,38 @@
* decompose_var_instance_name->get_next() when and if required...
*/
symbol_c *res = (symbol_c *)var_decl->accept(*this);
- if (NULL == res) ERROR;
+ /* NOTE: A Null result is not really an internal compiler error, but rather an error in
+ * the IEC 61131-3 source code being compiled. This means we cannot just abort the compiler with ERROR.
+ * // if (NULL == res) ERROR;
+ */
+ if (NULL == res) return NULL;
/* make sure that we have decomposed all structure elements of the variable name */
symbol_c *var_name = decompose_var_instance_name->next_part();
- if (NULL != var_name) ERROR;
+ /* NOTE: A non-NULL result is not really an internal compiler error, but rather an error in
+ * the IEC 61131-3 source code being compiled.
+ * (for example, 'int_var.struct_elem' in the source code, when 'int_var' is a simple integer,
+ * and not a structure, will result in this result being non-NULL!)
+ * This means we cannot just abort the compiler with ERROR.
+ * // if (NULL != var_name) ERROR;
+ */
+ if (NULL != var_name) return NULL;
return res;
}
+
+symbol_c *search_varfb_instance_type_c::get_basetype_decl(symbol_c *variable_name) {
+ symbol_c *res = get_type_decl(variable_name);
+ if (NULL == res) return NULL;
+ return (symbol_c *)base_type(res);
+}
+
+
unsigned int search_varfb_instance_type_c::get_vartype(symbol_c *variable_name) {
this->current_structelement_name = NULL;
- this->current_rawtype = NULL;
+ this->current_typeid = NULL;
+ this->current_basetypeid = NULL;
this->is_complex = false;
this->decompose_var_instance_name = new decompose_var_instance_name_c(variable_name);
if (NULL == decompose_var_instance_name) ERROR;
@@ -171,12 +190,12 @@
}
symbol_c *search_varfb_instance_type_c::get_type_id(symbol_c *variable_name) {
- this->current_rawtype = NULL;
- symbol_c *rawtype = this->get_basetype_decl(variable_name);
- if (this->current_rawtype != NULL)
- return this->current_rawtype;
+ this->current_typeid = NULL;
+ symbol_c *vartype = this->get_type_decl(variable_name);
+ if (this->current_typeid != NULL)
+ return this->current_typeid;
else
- return rawtype;
+ return vartype;
}
bool search_varfb_instance_type_c::type_is_complex(void) {
@@ -208,23 +227,40 @@
* of a function block type...
*/
void *search_varfb_instance_type_c::visit(identifier_c *type_name) {
+ /* we only store the new type id if none had been found yet.
+ * Since we will recursively carry on looking at the base type
+ * to determine the base type declaration and id, we must only set this variable
+ * the first time.
+ * e.g. TYPE myint1_t : int := 1;
+ * myint2_t : int1_t := 2;
+ * myint3_t : int2_t := 3;
+ * END_TYPE;
+ * VAR
+ * myint1 : myint1_t;
+ * myint2 : myint2_t;
+ * myint3 : myint3_t;
+ * END_VAR
+ *
+ * If we ask for typeid of myint3, it must return myint3_t
+ * If we ask for basetypeid of myint3, it must return int
+ *
+ * When determining the data type of myint3, we will recursively go all the way
+ * down to int, but we must still only store myint3_t as the base type id.
+ */
+ if (NULL == this->current_typeid)
+ this->current_typeid = type_name;
+ this->current_basetypeid = type_name;
+
/* look up the type declaration... */
symbol_c *fb_decl = function_block_type_symtable.find_value(type_name);
if (fb_decl != function_block_type_symtable.end_value())
/* Type declaration found!! */
return fb_decl->accept(*this);
- this->current_rawtype = type_name;
-
/* No. It is not a function block, so we let
* the base class take care of it...
*/
- if (NULL == decompose_var_instance_name->next_part(false)) {
- return base_type(type_name);
- }
- else {
- return search_base_type_c::visit(type_name);
- }
+ return search_base_type_c::visit(type_name);
}
/********************************/
@@ -251,8 +287,13 @@
}
/* structure_type_name ':' structure_specification */
+/* NOTE: this is only used inside a TYPE ... END_TYPE declaration.
+ * It is never used directly when declaring a new variable!
+ */
void *search_varfb_instance_type_c::visit(structure_type_declaration_c *symbol) {
this->is_complex = true;
+
+ if (NULL == current_structelement_name) ERROR;
return symbol->structure_specification->accept(*this);
/* NOTE: structure_specification will point to either a
* initialized_structure_c
@@ -264,52 +305,12 @@
/* structure_type_name ASSIGN structure_initialization */
/* structure_initialization may be NULL ! */
// SYM_REF2(initialized_structure_c, structure_type_name, structure_initialization)
+/* NOTE: only the initialized structure is ever used when declaring a new variable instance */
void *search_varfb_instance_type_c::visit(initialized_structure_c *symbol) {
this->is_complex = true;
- /* recursively find out the data type of var_name... */
- return symbol->structure_type_name->accept(*this);
-}
-
-/* helper symbol for structure_declaration */
-/* structure_declaration: STRUCT structure_element_declaration_list END_STRUCT */
-/* structure_element_declaration_list structure_element_declaration ';' */
-void *search_varfb_instance_type_c::visit(structure_element_declaration_list_c *symbol) {
- /* make sure that we have decomposed all structure elements of the variable name */
- current_structelement_name = decompose_var_instance_name->next_part();
- /* now search the structure declaration */
- return visit_list(symbol);
-}
-
-/* structure_element_name ':' spec_init */
-void *search_varfb_instance_type_c::visit(structure_element_declaration_c *symbol) {
- if (NULL == current_structelement_name) ERROR;
-
- if (compare_identifiers(symbol->structure_element_name, current_structelement_name) == 0)
- return symbol->spec_init->accept(*this);
-
- return NULL;
-}
-
-/* helper symbol for structure_initialization */
-/* structure_initialization: '(' structure_element_initialization_list ')' */
-/* structure_element_initialization_list ',' structure_element_initialization */
-void *search_varfb_instance_type_c::visit(structure_element_initialization_list_c *symbol) {ERROR; return NULL;} /* should never get called... */
-/* structure_element_name ASSIGN value */
-void *search_varfb_instance_type_c::visit(structure_element_initialization_c *symbol) {ERROR; return NULL;} /* should never get called... */
-
-
-
-/**************************************/
-/* B.1.5 - Program organization units */
-/**************************************/
-/*****************************/
-/* B 1.5.2 - Function Blocks */
-/*****************************/
-/* FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */
-// SYM_REF4(function_block_declaration_c, fblock_name, var_declarations, fblock_body, unused)
-void *search_varfb_instance_type_c::visit(function_block_declaration_c *symbol) {
+ if (NULL != current_structelement_name) ERROR;
+
/* make sure that we have decomposed all strcuture elements of the variable name */
-
symbol_c *var_name = decompose_var_instance_name->next_part();
if (NULL == var_name) {
/* this is it... !
@@ -322,6 +323,68 @@
return (void *)symbol;
}
+ /* look for the var_name in the structure declaration */
+ current_structelement_name = var_name;
+
+ /* recursively find out the data type of current_structelement_name... */
+ return symbol->structure_type_name->accept(*this);
+}
+
+/* helper symbol for structure_declaration */
+/* structure_declaration: STRUCT structure_element_declaration_list END_STRUCT */
+/* structure_element_declaration_list structure_element_declaration ';' */
+void *search_varfb_instance_type_c::visit(structure_element_declaration_list_c *symbol) {
+ if (NULL == current_structelement_name) ERROR;
+ /* now search the structure declaration */
+ return visit_list(symbol);
+}
+
+/* structure_element_name ':' spec_init */
+void *search_varfb_instance_type_c::visit(structure_element_declaration_c *symbol) {
+ if (NULL == current_structelement_name) ERROR;
+
+ if (compare_identifiers(symbol->structure_element_name, current_structelement_name) == 0) {
+ current_structelement_name = NULL;
+ /* found the type of the element we were looking for! */
+ return symbol->spec_init->accept(*this);
+ }
+
+ /* Did not find the type of the element we were looking for! */
+ /* Will keep looking... */
+ return NULL;
+}
+
+/* helper symbol for structure_initialization */
+/* structure_initialization: '(' structure_element_initialization_list ')' */
+/* structure_element_initialization_list ',' structure_element_initialization */
+void *search_varfb_instance_type_c::visit(structure_element_initialization_list_c *symbol) {ERROR; return NULL;} /* should never get called... */
+/* structure_element_name ASSIGN value */
+void *search_varfb_instance_type_c::visit(structure_element_initialization_c *symbol) {ERROR; return NULL;} /* should never get called... */
+
+
+
+/**************************************/
+/* B.1.5 - Program organization units */
+/**************************************/
+/*****************************/
+/* B 1.5.2 - Function Blocks */
+/*****************************/
+/* FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */
+// SYM_REF4(function_block_declaration_c, fblock_name, var_declarations, fblock_body, unused)
+void *search_varfb_instance_type_c::visit(function_block_declaration_c *symbol) {
+ /* make sure that we have decomposed all strcuture elements of the variable name */
+ symbol_c *var_name = decompose_var_instance_name->next_part();
+ if (NULL == var_name) {
+ /* this is it... !
+ * No need to look any further...
+ * Note also that, unlike for the struct types, a function block may
+ * not be defined based on another (i.e. no inheritance is allowed),
+ * so this function block is already the most base type.
+ * We simply return it.
+ */
+ return (void *)symbol;
+ }
+
/* now search the function block declaration for the variable... */
search_var_instance_decl_c search_decl(symbol);
symbol_c *var_decl = search_decl.get_decl(var_name);
@@ -329,7 +392,7 @@
/* variable instance declaration not found! */
return NULL;
}
-
+#if 0
/* We have found the declaration.
* Should we look any further?
*/
@@ -342,4 +405,7 @@
current_structelement_name = var_name;
/* recursively find out the data type of var_name... */
return symbol->var_declarations->accept(*this);
-}
+#endif
+ /* carry on recursively, in case the variable has more elements to be decomposed... */
+ return var_decl->accept(*this);
+}