Start to implement constant propagation algorithm.
/*
* matiec - a compiler for the programming languages defined in IEC 61131-3
*
* Copyright (C) 2003-2011 Mario de Sousa (msousa@fe.up.pt)
* Copyright (C) 2007-2011 Laurent Bessard and Edouard Tisserant
*
* 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)
*
*/
/*
* Function call parameter iterator.
*
* This is part of the 4th stage that generates
* a c++ source program equivalent to the IL and ST
* code.
*/
#include "../absyntax/visitor.hh"
/* given a function_body_c, iterate through each
* function/FB call in that code.
*/
class function_call_iterator_c : public iterator_visitor_c {
private:
symbol_c *start_symbol;
int next_fcall, fcall_count;
symbol_c *current_fcall_name;
symbol_c *current_finvocation;
public:
/* initialise the iterator object.
* We must be given a reference to the function declaration
* that will be analysed...
*/
function_call_iterator_c(symbol_c *symbol);
/* Skip to the next function call. After object creation,
* the object references _before_ the first, so
* this function must be called once to get the object to
* reference the first function call...
*
* Returns the function_invocation_c!
*/
symbol_c *next(void);
/* Returns the name of the currently referenced function invocation */
identifier_c *fname(void);
private:
/***************************************/
/* B.3 - Language ST (Structured Text) */
/***************************************/
/***********************/
/* B 3.1 - Expressions */
/***********************/
void *visit(function_invocation_c *symbol);
/****************************************/
/* B.2 - Language IL (Instruction List) */
/****************************************/
/***********************************/
/* B 2.1 Instructions and Operands */
/***********************************/
/* | function_name [il_operand_list] */
// SYM_REF2(il_function_call_c, function_name, il_operand_list)
void *visit(il_function_call_c *symbol);
/* | function_name '(' eol_list [il_param_list] ')' */
// SYM_REF2(il_formal_funct_call_c, function_name, il_param_list)
void *visit(il_formal_funct_call_c *symbol);
}; // class function_call_iterator_c