/*
* matiec - a compiler for the programming languages defined in IEC 61131-3
*
* Copyright (C) 2009-2012 Mario de Sousa (msousa@fe.up.pt)
* Copyright (C) 2012 Manuele Conti (conti.ma@alice.it)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*
* 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 compiler.
*
* Based on the
* FINAL DRAFT - IEC 61131-3, 2nd Ed. (2001-12-10)
*
*/
/* Determine the value of an constant expression.
* A reference to the relevant type definition is returned.
*
* For example:
* 2 + 3 -> returns reference
* 22.2 - 5 -> returns reference
* etc...
*/
#include <vector>
#include "../absyntax_utils/absyntax_utils.hh"
/* For the moment we disable constant propagation algorithm as it is not yet complete,
* and due to this is currently brocken and producing incorrect results!
*/
#define DO_CONSTANT_PROPAGATION__ 0
class constant_folding_c : public iterator_visitor_c {
search_varfb_instance_type_c *search_varfb_instance_type;
int error_count;
bool warning_found;
int current_display_error_level;
/* Pointer to the previous IL instruction, which contains the current cvalue of the data stored in the IL stack, i.e. the default variable, a.k.a. accumulator */
symbol_c *prev_il_instruction;
/* the current IL operand being analyzed */
symbol_c *il_operand;
public:
constant_folding_c(symbol_c *symbol = NULL);
virtual ~constant_folding_c(void);
int get_error_count();
#if 0
// not currently needed, so comment it out!...
/* utility functions for other stage3 algorithms to access the contant folded values */
/* written as static since we do not need to iteratively visit the symbols! */
// returns true if both symbols have the same value in all the cvalues
static bool is_equal_cvalue(symbol_c *symbol_1, symbol_c *symbol_2);
#endif
private:
/*********************/
/* B 1.2 - Constants */
/*********************/
/******************************/
/* B 1.2.1 - Numeric Literals */
/******************************/
void *visit(real_c *symbol);
void *visit(integer_c *symbol);
void *visit(neg_real_c *symbol);
void *visit(neg_integer_c *symbol);
void *visit(binary_integer_c *symbol);
void *visit(octal_integer_c *symbol);
void *visit(hex_integer_c *symbol);
void *visit(integer_literal_c *symbol);
void *visit(real_literal_c *symbol);
void *visit(bit_string_literal_c *symbol);
void *visit(boolean_literal_c *symbol);
void *visit(boolean_true_c *symbol);
void *visit(boolean_false_c *symbol);
/************************/
/* B 1.2.3.1 - Duration */
/********* **************/
void *visit(fixed_point_c *symbol);
/*********************/
/* B 1.4 - Variables */
/*********************/
#if DO_CONSTANT_PROPAGATION__
void *visit(symbolic_variable_c *symbol);
#endif
/**********************/
/* B 1.5.3 - Programs */
/**********************/
#if DO_CONSTANT_PROPAGATION__
void *visit(program_declaration_c *symbol);
#endif
/****************************************/
/* B.2 - Language IL (Instruction List) */
/****************************************/
/***********************************/
/* B 2.1 Instructions and Operands */
/***********************************/
// void *visit(instruction_list_c *symbol); /* Not needed, since we inherit from iterator_visitor_c */
void *visit(il_instruction_c *symbol);
void *visit(il_simple_operation_c *symbol);
//void *visit(il_function_call_c *symbol); /* TODO */
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); /* TODO */
//void *visit(il_operand_list_c *symbol); /* Not needed, since we inherit from iterator_visitor_c */
void *visit(simple_instr_list_c *symbol);
void *visit(il_simple_instruction_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); /* TODO */
#if DO_CONSTANT_PROPAGATION__
/*********************************/
/* B 3.2.1 Assignment Statements */
/*********************************/
void *visit(assignment_statement_c *symbol);
/********************************/
/* B 3.2.3 Selection Statements */
/********************************/
void *visit(if_statement_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);
#endif // DO_CONSTANT_PROPAGATION__
};