msousa@677: /*
msousa@677:  *  matiec - a compiler for the programming languages defined in IEC 61131-3
msousa@677:  *
msousa@677:  *  Copyright (C) 2012  Mario de Sousa (msousa@fe.up.pt)
msousa@677:  *
msousa@677:  *  This program is free software: you can redistribute it and/or modify
msousa@677:  *  it under the terms of the GNU General Public License as published by
msousa@677:  *  the Free Software Foundation, either version 3 of the License, or
msousa@677:  *  (at your option) any later version.
msousa@677:  *
msousa@677:  *  This program is distributed in the hope that it will be useful,
msousa@677:  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
msousa@677:  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
msousa@677:  *  GNU General Public License for more details.
msousa@677:  *
msousa@677:  *  You should have received a copy of the GNU General Public License
msousa@677:  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
msousa@677:  *
msousa@677:  *
msousa@677:  * This code is made available on the understanding that it will not be
msousa@677:  * used in safety-critical situations without a full and competent review.
msousa@677:  */
msousa@677: 
msousa@677: /*
msousa@677:  * An IEC 61131-3 compiler.
msousa@677:  *
msousa@677:  * Based on the
msousa@677:  * FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
msousa@677:  *
msousa@677:  */
msousa@677: 
msousa@677: 
msousa@677: /*
msousa@677:  *  Data type analysis of IL code may leave some IL instructions with an undefined datatype.
msousa@677:  *  This visitor will set the datatype for all these symbols, so that all symbols have a well 
msousa@677:  *  defined datatype when we reach stage4.
msousa@677:  *
msousa@677:  *  Example:
msousa@677:  * =========
msousa@677:  *
msousa@677:  *  VAR 
msousa@677:  *     N   : INT := 99 ;    
msousa@677:  *     tonv: TON;
msousa@677:  *     byte_var: BYTE;
msousa@677:  *     tonv : TON;
msousa@677:  *     a : BYTE;
msousa@677:  *     t : time;
msousa@677:  *     tod1: tod;
msousa@677:  *  END_VAR
msousa@677:  *  
msousa@677:  * (0) --> Data type before executing forced_narrow_candidate_datatypes_c
msousa@677:  * (1) --> Data type after executing 1st pass of forced_narrow_candidate_datatypes_c
msousa@677:  * (2) --> Data type after executing 2nd pass of forced_narrow_candidate_datatypes_c
msousa@677:  * 
msousa@677:  * --- --> NULL (undefined datatype)
msousa@677:  * *** --> invalid_type_name_c (invalid datatype)
msousa@677:  *
msousa@681:  * (0)   PASS1   (1)    PASS2   (2)
msousa@677:  *      
msousa@681:  * ---     (e)   ***            ***       CAL tonv (                          
msousa@681:  *                                               PT := T#1s                   
msousa@681:  *                                            )                               
msousa@681:  * ---     (e)   ***            ***       JMP l4                              
msousa@681:  *
msousa@681:  * ---     (e)   sint           sint  l0: LD  1                               
msousa@681:  * ---     (e)   sint           sint      ADD 2                               
msousa@681:  * ---  (c)      sint           sint      CAL tonv (                          
msousa@681:  *                                            PT := T#1s                      
msousa@681:  *                                            )                               
msousa@681:  *                                                                            
msousa@681:  * ---     (e)   sint           sint      LD  45                              
msousa@681:  * ---  (c)      sint           sint      ADD 45                              
msousa@681:  *
msousa@681:  *
msousa@681:  * ---     (e)   sint           sint      LD  3                               
msousa@681:  * ---     (e)   sint           sint  l1:                                     
msousa@681:  * ---  (c)      sint           sint  l2: ADD 4                               
msousa@681:  * int           int            int       LD  5                               
msousa@681:  * int           int            int       ST  n                               
msousa@681:  * int           int            int       JMP l3                              
msousa@681:  *                                                                            
msousa@681:  * ---  (d)      ---      (e)   sint      LD  5                               
msousa@681:  * ---  (d)      ---      (e)   sint      SUB 6                               
msousa@681:  * ---  (d)(e)   sint           sint      JMP l1                              
msousa@681:  *
msousa@681:  * ---     (e)   bool           bool      LD  FALSE                           
msousa@681:  * ---     (e)   bool           bool      NOT                                 
msousa@681:  * ---  (b)      bool           bool      RET                                 
msousa@681:  *
msousa@681:  * int           int            int   l3:                                     
msousa@681:  * int           int            int       ST  n                               
msousa@681:  * ---  (b)      int            int       RET                                 
msousa@681:  *
msousa@681:  * ---     (e)   ***            ***   l4:                                     
msousa@681:  * ---     (e)   ***            ***       CAL tonv (                          
msousa@681:  *                                               PT := T#1s                   
msousa@681:  *                                            )                               
msousa@681:  * ---  (a)      ***            ***       JMP l0                              
msousa@681:  * ---  (b)      byte           byte      LD  88                              
msousa@677:  *
msousa@677:  *
msousa@677:  *   
msousa@677:  */
msousa@677: 
msousa@677: 
msousa@677: 
msousa@677: #include "forced_narrow_candidate_datatypes.hh"
msousa@677: #include "datatype_functions.hh"
msousa@677: 
msousa@677: 
msousa@677: /* set to 1 to see debug info during execution */
msousa@677: static int debug = 0;
msousa@677: 
msousa@677: forced_narrow_candidate_datatypes_c::forced_narrow_candidate_datatypes_c(symbol_c *ignore) 
msousa@677:  :narrow_candidate_datatypes_c(ignore) {
msousa@677: }
msousa@677: 
msousa@677: forced_narrow_candidate_datatypes_c::~forced_narrow_candidate_datatypes_c(void) {
msousa@677: }
msousa@677: 
msousa@677: 
msousa@677: 
msousa@677: 
msousa@677: 
msousa@681: 
msousa@677: /****************************************/
msousa@677: /* B.2 - Language IL (Instruction List) */
msousa@677: /****************************************/
msousa@677: /***********************************/
msousa@677: /* B 2.1 Instructions and Operands */
msousa@677: /***********************************/
msousa@677: 
msousa@677: /*| instruction_list il_instruction */
msousa@677: // SYM_LIST(instruction_list_c)
msousa@677: void *forced_narrow_candidate_datatypes_c::visit(instruction_list_c *symbol) {
msousa@677:   for(int j = 0; j < 2; j++) {
msousa@677:     for(int i = symbol->n-1; i >= 0; i--) {
msousa@677:       symbol->elements[i]->accept(*this);
msousa@677:     }
msousa@677:   }
msousa@677: 
msousa@677:   /* Assert that this algorithm managed to remove all NULL datatypes! */
msousa@684:   /* NOTE: The forced_narrow_candidate_datatypes_c assumes that the original IEC 61131-3 source code does not have any bugs!
msousa@684:    *       This means we cannot run this assertion here, as the compiler will bork in the presence of bug in the code being compiled! Not good!!
msousa@684:    */
msousa@684:   /*
msousa@677:   for(int i = symbol->n-1; i >= 0; i--) {
msousa@677:     if (NULL == symbol->elements[i]->datatype)
msousa@677:       ERROR;
msousa@677:   }
msousa@684:   */
msousa@686:   
msousa@677:   return NULL;
msousa@677: }
msousa@677: 
msousa@677: 
msousa@677:   
msousa@677: /* | label ':' [il_incomplete_instruction] eol_list */
msousa@677: // SYM_REF2(il_instruction_c, label, il_instruction)
msousa@677: // void *visit(instruction_list_c *symbol);
msousa@677: void *forced_narrow_candidate_datatypes_c::visit(il_instruction_c *symbol) {
msousa@677:   if (NULL == symbol->datatype) {
msousa@677:     if (symbol->candidate_datatypes.empty()) {
msousa@677:       symbol->datatype = &(search_constant_type_c::invalid_type_name); // This will occur in the situations (a) in the above example
msousa@677:       // return NULL; // No need to return control to the visit() method of the base class... But we do so, just to be safe (called at the end of this function)!
msousa@677:     } else {
msousa@677:       if (symbol->next_il_instruction.empty()) {
msousa@677:         symbol->datatype = symbol->candidate_datatypes[0]; // This will occur in the situations (b) in the above example
msousa@677:       } else {
msousa@677:         symbol_c *next_datatype = NULL;
msousa@677: 
msousa@677:         /* find the datatype of the following IL instructions (they should all be identical by now, but we don't have an assertion checking for this. */
msousa@677:         for (unsigned int i=0; i < symbol->next_il_instruction.size(); i++)
msousa@677:           if (NULL != symbol->next_il_instruction[i]->datatype)
msousa@677:             next_datatype = symbol->next_il_instruction[i]->datatype;
msousa@677:         if (get_datatype_info_c::is_type_valid(next_datatype)) {
msousa@681:           //  This will occur in the situations (c) in the above example
msousa@677:           symbol->datatype = symbol->candidate_datatypes[0]; 
msousa@677:         } else {
msousa@681:           //  This will occur in the situations (d) in the above example
msousa@677:           // it is not possible to determine the exact situation in the current pass, so we can't do anything just yet. Leave it for the next time around!
msousa@677:         }
msousa@677:       }
msousa@677:     }
msousa@677:   }
msousa@677:   
msousa@677:   /* return control to the visit() method of the base class! */
msousa@681:   narrow_candidate_datatypes_c::visit(symbol);  //  This handle the situations (e) in the above example
msousa@677:   
msousa@677:   return NULL;
msousa@677: }
msousa@677: 
msousa@677: 
msousa@677: 
msousa@677: 
msousa@677: 
msousa@677: /* | il_simple_operator [il_operand] */
msousa@677: // SYM_REF2(il_simple_operation_c, il_simple_operator, il_operand)
msousa@677: // void *forced_narrow_candidate_datatypes_c::visit(il_simple_operation_c *symbol)
msousa@677: 
msousa@677: /* | function_name [il_operand_list] */
msousa@677: /* NOTE: The parameters 'called_function_declaration' and 'extensible_param_count' are used to pass data between the stage 3 and stage 4. */
msousa@677: // SYM_REF2(il_function_call_c, function_name, il_operand_list, symbol_c *called_function_declaration; int extensible_param_count;)
msousa@677: // void *forced_narrow_candidate_datatypes_c::visit(il_function_call_c *symbol) 
msousa@677: 
msousa@677: /* | il_expr_operator '(' [il_operand] eol_list [simple_instr_list] ')' */
msousa@677: // SYM_REF3(il_expression_c, il_expr_operator, il_operand, simple_instr_list);
msousa@677: // void *forced_narrow_candidate_datatypes_c::visit(il_expression_c *symbol)
msousa@677: 
msousa@677: /*  il_jump_operator label */
msousa@677: // SYM_REF2(il_jump_operation_c, il_jump_operator, label)
msousa@677: // void *forced_narrow_candidate_datatypes_c::visit(il_jump_operation_c *symbol)
msousa@677: 
msousa@677: /*   il_call_operator prev_declared_fb_name
msousa@677:  * | il_call_operator prev_declared_fb_name '(' ')'
msousa@677:  * | il_call_operator prev_declared_fb_name '(' eol_list ')'
msousa@677:  * | il_call_operator prev_declared_fb_name '(' il_operand_list ')'
msousa@677:  * | il_call_operator prev_declared_fb_name '(' eol_list il_param_list ')'
msousa@677:  */
msousa@677: /* NOTE: The parameter 'called_fb_declaration'is used to pass data between stage 3 and stage4 (although currently it is not used in stage 4 */
msousa@677: // SYM_REF4(il_fb_call_c, il_call_operator, fb_name, il_operand_list, il_param_list, symbol_c *called_fb_declaration)
msousa@677: // void *forced_narrow_candidate_datatypes_c::visit(il_fb_call_c *symbol)
msousa@677: 
msousa@677: /* | function_name '(' eol_list [il_param_list] ')' */
msousa@677: /* NOTE: The parameter 'called_function_declaration' is used to pass data between the stage 3 and stage 4. */
msousa@677: // SYM_REF2(il_formal_funct_call_c, function_name, il_param_list, symbol_c *called_function_declaration; int extensible_param_count;)
msousa@677: // void *forced_narrow_candidate_datatypes_c::visit(il_formal_funct_call_c *symbol)
msousa@677: 
msousa@677: // void *visit(il_operand_list_c *symbol);
msousa@677: // void *forced_narrow_candidate_datatypes_c::visit(simple_instr_list_c *symbol)
msousa@677: 
msousa@677: // SYM_REF1(il_simple_instruction_c, il_simple_instruction, symbol_c *prev_il_instruction;)
msousa@677: // void *forced_narrow_candidate_datatypes_c::visit(il_simple_instruction_c*symbol)
msousa@677: 
msousa@677: /*
msousa@677:     void *visit(il_param_list_c *symbol);
msousa@677:     void *visit(il_param_assignment_c *symbol);
msousa@677:     void *visit(il_param_out_assignment_c *symbol);
msousa@677:  */
msousa@677: 
msousa@681: 
msousa@681: 
msousa@681: /***************************************/
msousa@681: /* B.3 - Language ST (Structured Text) */
msousa@681: /***************************************/
msousa@681: // SYM_LIST(statement_list_c)
msousa@681: /* The normal narrow_candidate_datatypes_c algorithm does not leave any symbol, in an ST code, with an undefined datatype.
msousa@681:  * There is therefore no need to re-run the narrow algorithm here, so we overide the narrow_candidate_datatypes_c visitor,
msousa@681:  * and simply bug out!
msousa@681:  */
msousa@681: void *forced_narrow_candidate_datatypes_c::visit(statement_list_c *symbol) {return NULL;}
msousa@681: