Update some comments. (No changes to code)
/*
* matiec - a compiler for the programming languages defined in IEC 61131-3
*
* Copyright (C) 2003-2012 Mario de Sousa (msousa@fe.up.pt)
* Copyright (C) 2012 Manuele Conti (conti.ma@alice.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)
*
*/
/* Declaration sequence is a source code part needed to declare variables.
* There are some checks we need to do before start with other analysis:
*
* - Check external option redefinition.
* - Check external data type redefinition.
* - Check initial values consistently with the data types of the variables/data types being declared.
* - Check whether a function block uses a CONSTANT qualifier as described in 2.5.2.1.
*
*/
#include "declaration_check.hh"
#include "datatype_functions.hh"
#define FIRST_(symbol1, symbol2) (((symbol1)->first_order < (symbol2)->first_order) ? (symbol1) : (symbol2))
#define LAST_(symbol1, symbol2) (((symbol1)->last_order > (symbol2)->last_order) ? (symbol1) : (symbol2))
#define STAGE3_ERROR(error_level, symbol1, symbol2, ...) { \
if (current_display_error_level >= error_level) { \
fprintf(stderr, "%s:%d-%d..%d-%d: error: ", \
FIRST_(symbol1,symbol2)->first_file, FIRST_(symbol1,symbol2)->first_line, FIRST_(symbol1,symbol2)->first_column,\
LAST_(symbol1,symbol2) ->last_line, LAST_(symbol1,symbol2) ->last_column);\
fprintf(stderr, __VA_ARGS__); \
fprintf(stderr, "\n"); \
error_count++; \
} \
}
#define STAGE3_WARNING(symbol1, symbol2, ...) { \
fprintf(stderr, "%s:%d-%d..%d-%d: warning: ", \
FIRST_(symbol1,symbol2)->first_file, FIRST_(symbol1,symbol2)->first_line, FIRST_(symbol1,symbol2)->first_column,\
LAST_(symbol1,symbol2) ->last_line, LAST_(symbol1,symbol2) ->last_column);\
fprintf(stderr, __VA_ARGS__); \
fprintf(stderr, "\n"); \
warning_found = true; \
}
#include <set>
class check_extern_c: public iterator_visitor_c {
public:
private:
int current_display_error_level;
symbol_c *current_pou_decl;
symbol_c *current_resource_decl;
static std::set<symbol_c *> checked_decl; // A set with all the declarations that have already been checked, so we don't recheck it again!
public:
static int error_count;
check_extern_c(symbol_c *current_pou, symbol_c *current_resource) {
current_display_error_level = 0;
current_pou_decl = current_pou;
current_resource_decl = current_resource;
}
~check_extern_c(void) {}
void check_global_decl(symbol_c *p_decl) {
if (NULL == current_pou_decl) ERROR;
if (checked_decl.find(p_decl) != checked_decl.end()) return; // has already been checked!
checked_decl.insert(p_decl);
search_var_instance_decl_c search_var_instance_pou_glo_decl(current_pou_decl);
search_var_instance_decl_c search_var_instance_res_glo_decl(current_resource_decl);
search_var_instance_decl_c search_var_instance_ext_decl(p_decl);
function_param_iterator_c fpi(p_decl);
symbol_c *var_name;
while((var_name = fpi.next()) != NULL) {
if (fpi.param_direction() == function_param_iterator_c::direction_extref) {
/* found an external reference parameter. */
symbol_c *ext_decl = search_var_instance_ext_decl.get_decl(var_name);
// NOTE: Must check the POU first, and RESOURCE second!
symbol_c *glo_decl = search_var_instance_res_glo_decl.get_decl(var_name);
search_var_instance_decl_c *search_var_instance_glo_decl = &search_var_instance_res_glo_decl;
if (NULL == glo_decl) {
glo_decl = search_var_instance_pou_glo_decl.get_decl(var_name);
search_var_instance_glo_decl = &search_var_instance_pou_glo_decl;
}
if (NULL == glo_decl) {
STAGE3_ERROR(0, ext_decl, ext_decl, "Declaration error. The external variable does not match with any global variable.");
continue;
}
/* Check whether variable's constness (CONSTANT) is compatible.
* VAR_GLOBAL is contant => VAR_EXTERNAL must also be CONSTANT
* VAR_GLOBAL is not contant => VAR_EXTERNAL may be CONSTANT, or not!
*/
search_var_instance_decl_c::opt_t ext_opt = search_var_instance_ext_decl. get_option(var_name);
search_var_instance_decl_c::opt_t glo_opt = search_var_instance_glo_decl->get_option(var_name);
if ((glo_opt == search_var_instance_decl_c::constant_opt) && (ext_opt != search_var_instance_decl_c::constant_opt))
STAGE3_ERROR(0, glo_decl, glo_decl, "Declaration error. The external variable must be declared as constant, as it maps to a constant global variable.");
/* TODO: Check redefinition data type.
* We need a new class (like search_base_type class) to get type id by variable declaration.
* symbol_c *glo_type = ????;
* symbol_c *ext_type = fpi.param_type();
*/
/* For the moment, we will just use search_base_type_c instead... */
symbol_c *glo_type = search_base_type_c::get_basetype_decl(glo_decl);
symbol_c *ext_type = search_base_type_c::get_basetype_decl(ext_decl);
if (! get_datatype_info_c::is_type_equal(glo_type, ext_type))
STAGE3_ERROR(0, ext_decl, ext_decl, "Declaration error. Data type mismatch between external and global variable declarations.");
}
}
}
/********************************/
/* B 1.3.3 - Derived data types */
/********************************/
/* function_block_type_name ASSIGN structure_initialization */
/* structure_initialization -> may be NULL ! */
//SYM_REF2(fb_spec_init_c, function_block_type_name, structure_initialization)
/* NOTE: This class is only used when declaring FB variables, as in:
* name_list ':' function_block_type_name ASSIGN structure_initialization
* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* fb_spec_init_c
* Here, fb_spec_init_c is used whether it is an external, local, or global variable!
* Note too that we must also check the datatypes of external and global variables!!
*/
void *visit(fb_spec_init_c *symbol) {
symbol_c *fb_decl = function_block_type_symtable.find_value(symbol->function_block_type_name);
/* stage1_2 guarantees that we are sure to find a declaration in FB or Program symtable. */
if (fb_decl == function_block_type_symtable.end_value())
ERROR;
fb_decl->accept(*this);
return NULL;
}
/*****************************/
/* B 1.5.2 - Function Blocks */
/*****************************/
/* FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */
// SYM_REF3(function_block_declaration_c, fblock_name, var_declarations, fblock_body)
void *visit(function_block_declaration_c *symbol) {
check_global_decl(symbol);
/* The following two lines of code are only valid for v3 of IEC 61131-3, that allows VAR_GLOBAL declarations inside FBs!
* current_pou_decl = symbol;
* current_resource_decl = NULL;
*/
/* check if any FB declared as a VAR has any incompatible VAR_EXTERNAL declarations */
if (NULL != symbol->var_declarations)
symbol->var_declarations->accept(*this); // This will eventually call the visit(fb_spec_init_c *) method, if any FB are declared here!
return NULL;
}
/******************************************/
/* B 1.5.3 - Declaration & Initialisation */
/******************************************/
/* PROGRAM program_type_name program_var_declarations_list function_block_body END_PROGRAM */
// SYM_REF3(program_declaration_c, program_type_name, var_declarations, function_block_body)
void *visit(program_declaration_c *symbol) {
check_global_decl(symbol);
/* The following two lines of code are only valid for v3 of IEC 61131-3, that allows VAR_GLOBAL declarations inside PROGRAMs!
* current_pou_decl = symbol;
* current_resource_decl = NULL;
*/
/* check if any FB declared as a VAR has any incompatible VAR_EXTERNAL declarations */
if (NULL != symbol->var_declarations)
symbol->var_declarations->accept(*this); // This will eventually call the visit(fb_spec_init_c *) method, if any FB are declared here!
return NULL;
}
};
int check_extern_c::error_count = 0;
std::set<symbol_c *> check_extern_c::checked_decl;
declaration_check_c::declaration_check_c(symbol_c *ignore) {
current_display_error_level = 0;
current_pou_decl = NULL;
current_resource_decl = NULL;
error_count = 0;
}
declaration_check_c::~declaration_check_c(void) {
}
int declaration_check_c::get_error_count() {
return check_extern_c::error_count;
}
/*****************************/
/* B 1.5.2 - Function Blocks */
/*****************************/
/* FUNCTION_BLOCK derived_function_block_name io_OR_other_var_declarations function_block_body END_FUNCTION_BLOCK */
// SYM_REF3(function_block_declaration_c, fblock_name, var_declarations, fblock_body)
void *declaration_check_c::visit(function_block_declaration_c *symbol)
{return NULL;} // We only check the declarations that are used to instantiate variables. This is done in the configuration!
/******************************************/
/* B 1.5.3 - Declaration & Initialisation */
/******************************************/
/* PROGRAM program_type_name program_var_declarations_list function_block_body END_PROGRAM */
// SYM_REF3(program_declaration_c, program_type_name, var_declarations, function_block_body)
void *declaration_check_c::visit(program_declaration_c *symbol)
{return NULL;} // We only check the declarations that are used to instantiate variables. This is done in the configuration!
/********************************/
/* B 1.7 Configuration elements */
/********************************/
/*
* CONFIGURATION configuration_name
* optional_global_var_declarations
* (resource_declaration_list | single_resource_declaration)
* optional_access_declarations
* optional_instance_specific_initializations
* END_CONFIGURATION
*/
//SYM_REF5(configuration_declaration_c, configuration_name, global_var_declarations, resource_declarations, access_declarations, instance_specific_initializations)
void *declaration_check_c::visit(configuration_declaration_c *symbol) {
current_pou_decl = symbol;
/* check if any FB declared as a VAR has any incompatible VAR_EXTERNAL declarations */
if (NULL != symbol->resource_declarations)
symbol->resource_declarations->accept(*this);
current_pou_decl = NULL;
return NULL;
}
/*
RESOURCE resource_name ON resource_type_name
optional_global_var_declarations
single_resource_declaration
END_RESOURCE
*/
/* enumvalue_symtable is filled in by enum_declaration_check_c, during stage3 semantic verification, with a list of all enumerated constants declared inside this POU */
// SYM_REF4(resource_declaration_c, resource_name, resource_type_name, global_var_declarations, resource_declaration, enumvalue_symtable_t enumvalue_symtable;)
void *declaration_check_c::visit(resource_declaration_c *symbol) {
// check if any FB instantiated inside this resource (in a VAR_GLOBAL) has any VAR_EXTERNAL declarations incompatible with the configuration's VAR_GLOBALs
check_extern_c check_extern(current_pou_decl, current_resource_decl);
symbol->global_var_declarations->accept(check_extern);
// Now check the Programs instantiated in this resource
current_resource_decl = symbol;
symbol->resource_declaration->accept(*this);
current_resource_decl = NULL;
return NULL;
}
/* PROGRAM [RETAIN | NON_RETAIN] program_name [WITH task_name] ':' program_type_name ['(' prog_conf_elements ')'] */
void *declaration_check_c::visit(program_configuration_c *symbol) {
symbol_c *p_decl = program_type_symtable.find_value(symbol->program_type_name);
if (p_decl == program_type_symtable.end_value())
p_decl = function_block_type_symtable.find_value(symbol->program_type_name);
if (p_decl == function_block_type_symtable.end_value())
ERROR; // Should never occur! stage1_2 guarantees that we are sure to find a declaration in FB or Program symtable.
check_extern_c check_extern(current_pou_decl, current_resource_decl);
p_decl->accept(check_extern);
return NULL;
}