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 

    26 

    27 

    28 /* Returns the data type of an il_operand.

    29  *

    30  * Note that the il_operand may be a variable, in which case

    31  * we return the type of the variable instance.

    32  * The il_operand may also be a constant, in which case

    33  * we return the data type of that constant.

    34  *

    35  * The variable instance may be a member of a structured variable,

    36  * or an element in an array, or any combination of the two.

    37  *

    38  * The class constructor must be given the search scope

    39  * (function, function block or program within which

    40  * the possible il_operand variable instance was declared).

    41  */

    42 

    43 

    44 

    45 symbol_c *search_il_operand_type_c::get_type(symbol_c *il_operand) {

    46   symbol_c *res;

    47 

    48   /* We first assume that it is a constant... */

    49   res = search_constant_type.get_type(il_operand);

    50   if (res != NULL) return res;

    51 

    52   /* Nope, now we assume it is a variable, and determine its type... */

    53   res = search_varfb_instance_type.get_type(il_operand);

    54   if (NULL != res) return res;

    55 

    56   /* not found */

    57   return NULL;

    58 }