diff -r b8a2f4c86745 -r 8ffa211b7f9a stage3/visit_expression_type.hh --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/stage3/visit_expression_type.hh Thu Aug 27 16:29:23 2009 +0100 @@ -0,0 +1,294 @@ +/* + * (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); + + /* A helper function... */ + bool is_ANY_ELEMENTARY_type(symbol_c *type_symbol); + bool is_ANY_MAGNITUDE_type(symbol_c *type_symbol); + bool is_ANY_DATE_type(symbol_c *type_symbol); + bool is_ANY_STRING_type(symbol_c *type_symbol); + bool is_ANY_INT_type(symbol_c *type_symbol); + bool is_ANY_REAL_type(symbol_c *type_symbol); + bool is_ANY_NUM_type(symbol_c *type_symbol); + bool is_ANY_BIT_type(symbol_c *type_symbol); + bool is_BOOL_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 there is a common data type, otherwise return FALSE */ + 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); + + /* 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 +