/*
* (c) 2003 Mario de Sousa
*
* Offered to the public under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2 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.
*
* 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 IL and ST compiler.
*
* Based on the
* FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
*
*/
/* Verify whether the semantic rules of data type compatibility are being followed.
*
* For example:
*/
#include "../absyntax_utils/absyntax_utils.hh"
class visit_expression_type_c: public search_constant_type_c {
private:
search_varfb_instance_type_c *search_varfb_instance_type;
search_base_type_c search_base_type;
/* When calling a function block, we must first find it's type,
* by searching through the declarations of the variables currently
* in scope.
* This class does just that...
* A new bject instance is instantiated whenever we start checking semantics
* for a function block type declaration, or a program declaration.
* This object instance will then later be called while the
* function block's or the program's body is being handled.
*
* Note that functions cannot contain calls to function blocks,
* so we do not create an object instance when handling
* a function declaration.
*/
// search_var_instance_decl_c *search_var_instance_decl;
/* This variable was created to pass information from
* visit_expression_type_c::visit(case_statement_c *symbol) function to
* visit_expression_type_c::visit(case_list_c *symbol) function.
*/
symbol_c *case_expression_type;
/* In IL code, once we find a type mismatch error, it is best to
* ignore any further errors until the end of the logicl operation,
* i.e. until the next LD.
* However, we cannot clear the il_error flag on all LD operations,
* as these may also be used within parenthesis. LD operations
* within parenthesis may not clear the error flag.
* We therefore need a counter to know how deep inside a parenthesis
* structure we are.
*/
int il_parenthesis_level;
bool il_error;
symbol_c *il_default_variable_type;
symbol_c *il_operand_type;
public:
visit_expression_type_c(symbol_c *search_scope);
virtual ~visit_expression_type_c(void);
typedef struct {
symbol_c *value;
symbol_c *type;
} value_and_type_t;
/* A helper function... */
bool is_ANY_ELEMENTARY_type (symbol_c *type_symbol);
bool is_ANY_SAFEELEMENTARY_type (symbol_c *type_symbol);
bool is_ANY_ELEMENTARY_compatible (symbol_c *type_symbol);
bool is_ANY_MAGNITUDE_type (symbol_c *type_symbol);
bool is_ANY_SAFEMAGNITUDE_type (symbol_c *type_symbol);
bool is_ANY_MAGNITUDE_compatible (symbol_c *type_symbol);
bool is_ANY_DATE_type (symbol_c *type_symbol);
bool is_ANY_SAFEDATE_type (symbol_c *type_symbol);
bool is_ANY_DATE_compatible (symbol_c *type_symbol);
bool is_ANY_STRING_type (symbol_c *type_symbol);
bool is_ANY_SAFESTRING_type (symbol_c *type_symbol);
bool is_ANY_STRING_compatible (symbol_c *type_symbol);
bool is_ANY_INT_type (symbol_c *type_symbol);
bool is_ANY_SAFEINT_type (symbol_c *type_symbol);
bool is_ANY_INT_compatible (symbol_c *type_symbol);
bool is_ANY_REAL_type (symbol_c *type_symbol);
bool is_ANY_SAFEREAL_type (symbol_c *type_symbol);
bool is_ANY_REAL_compatible (symbol_c *type_symbol);
bool is_ANY_NUM_type (symbol_c *type_symbol);
bool is_ANY_SAFENUM_type (symbol_c *type_symbol);
bool is_ANY_NUM_compatible (symbol_c *type_symbol);
bool is_ANY_BIT_type (symbol_c *type_symbol);
bool is_ANY_SAFEBIT_type (symbol_c *type_symbol);
bool is_ANY_BIT_compatible (symbol_c *type_symbol);
bool is_BOOL_type (symbol_c *type_symbol);
bool is_SAFEBOOL_type (symbol_c *type_symbol);
bool is_ANY_BOOL_compatible (symbol_c *type_symbol);
bool is_nonneg_literal_integer_type (symbol_c *type_symbol);
bool is_literal_integer_type (symbol_c *type_symbol);
bool is_literal_real_type (symbol_c *type_symbol);
bool is_literal_bool_type (symbol_c *type_symbol);
/* Determine the common data type between two data types.
* If no common data type found, return NULL.
*
* If data types are identical, return the first (any would do...).
* If any of the datat types is a literal, we confirm that
* the literal uses less bits than the fixed size data type.
* e.g. BYTE and 1024 returns NULL
* BYTE and 255 returns BYTE
*
* If two literals, then return the literal that requires more bits...
*/
symbol_c *common_type__(symbol_c *first_type, symbol_c *second_type);
/* Determine the common data type between two data types.
* Unlike the common_type__() function, we stop the compiler with an ERROR
* if no common data type is found.
*/
symbol_c *common_type(symbol_c *first_type, symbol_c *second_type);
/* Return TRUE if the second (value) data type may be assigned to a variable of the first (variable) data type
* such as:
* var_type value_type
* BOOL BYTE#7 -> returns false
* INT INT#7 -> returns true
* INT 7 -> returns true
* REAL 7.89 -> returns true
* REAL 7 -> returns true
* INT 7.89 -> returns false
* SAFEBOOL BOOL#1 -> returns false !!!
* etc...
*
* NOTE: It is assumed that the var_type is the data type of an lvalue
*/
bool is_valid_assignment(symbol_c *var_type, symbol_c *value_type);
/* Return TRUE if there is a common data type, otherwise return FALSE
* i.e., return TRUE if both data types may be used simultaneously in an expression
* such as:
* BOOL#0 AND BYTE#7 -> returns false
* 0 AND BYTE#7 -> returns true
* INT#10 AND INT#7 -> returns true
* INT#10 AND 7 -> returns true
* REAL#34.3 AND 7.89 -> returns true
* REAL#34.3 AND 7 -> returns true
* INT#10 AND 7.89 -> returns false
* SAFEBOOL#0 AND BOOL#1 -> returns true !!!
* etc...
*/
bool is_compatible_type(symbol_c *first_type, symbol_c *second_type);
void compute_input_operatores(symbol_c *symbol, const char *input_operator);
void check_formal_parameter(symbol_c *call_param_name, symbol_c *call_param_type, symbol_c *f_decl);
/* check the semantics of a FB or Function non-formal call */
/* e.g. foo(1, 2, 3, 4); */
void check_nonformal_call(symbol_c *f_call, symbol_c *f_decl, bool use_il_defvar = false);
/* check the semantics of a FB or Function formal call */
/* e.g. foo(IN1 := 1, OUT1 =>x, EN := true); */
void check_formal_call(symbol_c *f_call, symbol_c *f_decl);
void *compute_standard_function_default(function_invocation_c *st_symbol, il_formal_funct_call_c *il_symbol);
void *compute_standard_function_il(il_function_call_c *symbol, symbol_c *param_data_type);
/* A helper function... */
typedef bool (visit_expression_type_c::*is_data_type_t)(symbol_c *type_symbol); /* a pointer to a function! */
// symbol_c *compute_boolean_expression(symbol_c *left_exp, symbol_c *right_exp, is_data_type_t is_data_type);
// symbol_c *compute_numeric_expression(symbol_c *left_exp, symbol_c *right_exp, is_data_type_t is_data_type);
symbol_c *compute_expression(symbol_c *left_exp, symbol_c *right_exp, is_data_type_t is_data_type);
/* a helper function... */
symbol_c *base_type(symbol_c *symbol);
/* a helper function... */
void *verify_null(symbol_c *symbol);
/*********************/
/* B 1.4 - Variables */
/*********************/
void *visit(symbolic_variable_c *symbol);
/********************************************/
/* B 1.4.1 - Directly Represented Variables */
/********************************************/
void *visit(direct_variable_c *symbol);
/*************************************/
/* B 1.4.2 - Multi-element variables */
/*************************************/
void *visit(array_variable_c *symbol);
void *visit(structured_variable_c *symbol);
/****************************************/
/* B.2 - Language IL (Instruction List) */
/****************************************/
/***********************************/
/* B 2.1 Instructions and Operands */
/***********************************/
// void *visit(instruction_list_c *symbol);
void *visit(il_simple_operation_c *symbol);
void *visit(il_function_call_c *symbol);
void *visit(il_expression_c *symbol);
// void *visit(il_jump_operation_c *symbol);
void *visit(il_fb_call_c *symbol);
void *visit(il_formal_funct_call_c *symbol);
/*
void *visit(il_operand_list_c *symbol);
void *visit(simple_instr_list_c *symbol);
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 *visit(LD_operator_c *symbol);
void *visit(LDN_operator_c *symbol);
void *visit(ST_operator_c *symbol);
void *visit(STN_operator_c *symbol);
void *visit(NOT_operator_c *symbol);
void *visit(S_operator_c *symbol);
void *visit(R_operator_c *symbol);
void *visit(S1_operator_c *symbol);
void *visit(R1_operator_c *symbol);
void *visit(CLK_operator_c *symbol);
void *visit(CU_operator_c *symbol);
void *visit(CD_operator_c *symbol);
void *visit(PV_operator_c *symbol);
void *visit(IN_operator_c *symbol);
void *visit(PT_operator_c *symbol);
void *visit(AND_operator_c *symbol);
void *visit(OR_operator_c *symbol);
void *visit(XOR_operator_c *symbol);
void *visit(ANDN_operator_c *symbol);
void *visit(ORN_operator_c *symbol);
void *visit(XORN_operator_c *symbol);
void *visit(ADD_operator_c *symbol);
void *visit(SUB_operator_c *symbol);
void *visit(MUL_operator_c *symbol);
void *visit(DIV_operator_c *symbol);
void *visit(MOD_operator_c *symbol);
void *visit(GT_operator_c *symbol);
void *visit(GE_operator_c *symbol);
void *visit(EQ_operator_c *symbol);
void *visit(LT_operator_c *symbol);
void *visit(LE_operator_c *symbol);
void *visit(NE_operator_c *symbol);
void *visit(CAL_operator_c *symbol);
void *visit(CALC_operator_c *symbol);
void *visit(CALCN_operator_c *symbol);
void *visit(RET_operator_c *symbol);
void *visit(RETC_operator_c *symbol);
void *visit(RETCN_operator_c *symbol);
void *visit(JMP_operator_c *symbol);
void *visit(JMPC_operator_c *symbol);
void *visit(JMPCN_operator_c *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 *visit(or_expression_c *symbol);
void *visit(xor_expression_c *symbol);
void *visit(and_expression_c *symbol);
void *visit(equ_expression_c *symbol);
void *visit(notequ_expression_c *symbol);
void *visit(lt_expression_c *symbol);
void *visit(gt_expression_c *symbol);
void *visit(le_expression_c *symbol);
void *visit(ge_expression_c *symbol);
void *visit(add_expression_c *symbol);
void *visit(sub_expression_c *symbol);
void *visit(mul_expression_c *symbol);
void *visit(div_expression_c *symbol);
void *visit(mod_expression_c *symbol);
void *visit(power_expression_c *symbol);
void *visit(neg_expression_c *symbol);
void *visit(not_expression_c *symbol);
void *visit(function_invocation_c *symbol);
/*********************************/
/* B 3.2.1 Assignment Statements */
/*********************************/
void *visit(assignment_statement_c *symbol);
/*****************************************/
/* B 3.2.2 Subprogram Control Statements */
/*****************************************/
void *visit(fb_invocation_c *symbol);
/********************************/
/* B 3.2.3 Selection Statements */
/********************************/
void *visit(if_statement_c *symbol);
// void *visit(elseif_statement_list_c *symbol);
void *visit(elseif_statement_c *symbol);
void *visit(case_statement_c *symbol);
// void *visit(case_element_list_c *symbol);
// void *visit(case_element_c *symbol);
void *visit(case_list_c *symbol);
/********************************/
/* B 3.2.4 Iteration Statements */
/********************************/
void *visit(for_statement_c *symbol);
void *visit(while_statement_c *symbol);
void *visit(repeat_statement_c *symbol);
//TODO: delete this functions. Why are they needed?
void *visit(program_declaration_c *symbol);
void *visit(function_declaration_c *symbol);
void *visit(function_block_declaration_c *symbol);
}; // visit_expression_type_c