diff -r bd5998ee8876 -r ff4d26b7e51d stage3/flow_control_analysis.hh
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/stage3/flow_control_analysis.hh	Thu Feb 16 10:27:52 2012 +0000
@@ -0,0 +1,161 @@
+/*
+ *  matiec - a compiler for the programming languages defined in IEC 61131-3
+ *
+ *  Copyright (C) 2012  Mario de Sousa (msousa@fe.up.pt)
+ *
+ *
+ *  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)
+ *
+ */
+
+
+/*
+ *  Do flow control analysis of the IEC 61131-3 code.
+ *
+ *  We currently only do this for IL code.
+ *  This class will annotate the abstract syntax tree, by filling in the
+ *  prev_il_instruction variable in the il_instruction_c, so it points to
+ *  the previous il_instruction_c object in the instruction list instruction_list_c.
+ */
+
+
+
+#include "../absyntax_utils/absyntax_utils.hh"
+
+
+class flow_control_analysis_c: public iterator_visitor_c {
+
+  private:
+    search_varfb_instance_type_c *search_varfb_instance_type;
+    symbol_c *prev_il_instruction;
+
+  public:
+    flow_control_analysis_c(symbol_c *ignore);
+    virtual ~flow_control_analysis_c(void);
+
+    /**************************************/
+    /* B 1.5 - Program organization units */
+    /**************************************/
+    /***********************/
+    /* B 1.5.1 - Functions */
+    /***********************/
+    void *visit(function_declaration_c *symbol);
+
+    /*****************************/
+    /* B 1.5.2 - Function blocks */
+    /*****************************/
+    void *visit(function_block_declaration_c *symbol);
+
+    /**********************/
+    /* B 1.5.3 - Programs */
+    /**********************/
+    void *visit(program_declaration_c *symbol);
+
+    /********************************/
+    /* B 1.7 Configuration elements */
+    /********************************/
+    void *visit(configuration_declaration_c *symbol);
+    
+    /****************************************/
+    /* B.2 - Language IL (Instruction List) */
+    /****************************************/
+    /***********************************/
+    /* B 2.1 Instructions and Operands */
+    /***********************************/
+    void *visit(instruction_list_c *symbol);
+    void *visit(il_instruction_c *symbol);
+//     void *visit(il_simple_operation_c *symbol);
+//     void *visit(il_function_call_c *symbol);
+//     void *visit(il_expression_c *symbol);
+//     void *visit(il_fb_call_c *symbol);
+//     void *visit(il_formal_funct_call_c *symbol);
+    /*
+        void *visit(il_operand_list_c *symbol);
+        void *visit(simple_instr_list_c *symbol);
+        void *visit(il_param_list_c *symbol);
+        void *visit(il_param_assignment_c *symbol);
+        void *visit(il_param_out_assignment_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);
+
+}; // flow_control_analysis_c
+
+
+
+
+
+
+
+