1 /*

     2  * (c) 2003 Mario de Sousa

     3  *

     4  * Offered to the public under the terms of the GNU General Public License

     5  * as published by the Free Software Foundation; either version 2 of the

     6  * License, or (at your option) any later version.

     7  *

     8  * This program is distributed in the hope that it will be useful, but

     9  * WITHOUT ANY WARRANTY; without even the implied warranty of

    10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General

    11  * Public License for more details.

    12  *

    13  * This code is made available on the understanding that it will not be

    14  * used in safety-critical situations without a full and competent review.

    15  */

    16 

    17 /*

    18  * An IEC 61131-3 IL and ST compiler.

    19  *

    20  * Based on the

    21  * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)

    22  *

    23  */

    24 

    25 /* Determine the data type of an ST expression.

    26  * A reference to the relevant type definition is returned.

    27  *

    28  * For example:

    29  *       2 + 3       -> returns reference to a int_type_name_c object.

    30  *       22.2 - 5    -> returns reference to a real_type_name_c object.

    31  *       etc...

    32  */

    33 

    34 class search_expression_type_c: public search_constant_type_c {

    35 

    36   private:

    37     search_varfb_instance_type_c *search_varfb_instance_type;

    38     search_base_type_c search_base_type;

    39 

    40 

    41   public:

    42     search_expression_type_c(symbol_c *search_scope);

    43     virtual ~search_expression_type_c(void);

    44 

    45     /* A helper function... */

    46     bool is_bool_type(symbol_c *type_symbol);

    47     bool is_time_type(symbol_c *type_symbol);

    48     bool is_string_type(symbol_c *type_symbol);

    49     bool is_integer_type(symbol_c *type_symbol);

    50     bool is_real_type(symbol_c *type_symbol);

    51     bool is_num_type(symbol_c *type_symbol);

    52     bool is_nbinary_type(symbol_c *type_symbol);

    53     bool is_binary_type(symbol_c *type_symbol);

    54 

    55     bool is_same_type(symbol_c *first_type, symbol_c *second_type);

    56     symbol_c* common_type(symbol_c *first_type, symbol_c *second_type);

    57 

    58     /*

    59     #include "search_type_code.c"

    60     */

    61     void *compute_standard_function_default(function_invocation_c *st_symbol, il_formal_funct_call_c *il_symbol);

    62     /*

    63     void *compute_standard_function_default(function_invocation_c *st_symbol = NULL, il_formal_funct_call_c *il_symbol = NULL);

    64     */

    65     void *compute_standard_function_il(il_function_call_c *symbol, symbol_c *param_data_type);

    66 

    67 

    68 

    69     /*static bool_type_name_c bool_type_name;*/

    70 

    71     /* A helper function... */

    72     void *compute_boolean_expression(symbol_c *left_type, symbol_c *right_type);

    73 

    74     /* A helper function... */

    75     void *compute_numeric_expression(symbol_c *left_type, symbol_c *right_type);

    76 

    77     /* a helper function... */

    78     symbol_c *base_type(symbol_c *symbol);

    79 

    80     /*********************/

    81     /* B 1.4 - Variables */

    82     /*********************/

    83     

    84     void *visit(symbolic_variable_c *symbol);

    85 

    86     /********************************************/

    87     /* B 1.4.1 - Directly Represented Variables */

    88     /********************************************/

    89     void *visit(direct_variable_c *symbol);

    90 

    91     /*************************************/

    92     /* B 1.4.2 - Multi-element variables */

    93     /*************************************/

    94  

    95     void *visit(array_variable_c *symbol);

    96     void *visit(structured_variable_c *symbol);

    97 

    98     /***************************************/

    99     /* B.3 - Language ST (Structured Text) */

   100     /***************************************/

   101     /***********************/

   102     /* B 3.1 - Expressions */

   103     /***********************/

   104     void *visit(or_expression_c *symbol);

   105     void *visit(xor_expression_c *symbol);

   106     void *visit(and_expression_c *symbol);

   107     void *visit(equ_expression_c *symbol);

   108     void *visit(notequ_expression_c *symbol);

   109     void *visit(lt_expression_c *symbol);

   110     void *visit(gt_expression_c *symbol);

   111     void *visit(le_expression_c *symbol);

   112     void *visit(ge_expression_c *symbol);

   113     

   114     void *visit(add_expression_c *symbol);

   115     void *visit(sub_expression_c *symbol);

   116     void *visit(mul_expression_c *symbol);

   117     void *visit(div_expression_c *symbol);

   118     void *visit(mod_expression_c *symbol);

   119     void *visit(power_expression_c *symbol);

   120     void *visit(neg_expression_c *symbol);

   121     void *visit(not_expression_c *symbol);

   122     void *visit(function_invocation_c *symbol);

   123 }; // search_expression_type_c

   124 

   125 /*bool_type_name_c     search_expression_type_c::bool_type_name;*/

   126