parser.java

我开发的一个用java语言实现的编译器,内含词法分析器,语法分析器,而且可以实现中间代码生成.用到了SLR算法和LR(1)算法

    "\001\000\002\001\001\000\002\001\001\000\002\001\001" +
    "\000\002\001\001\000\004\061\042\001\001\000\002\001" +
    "\001\000\002\001\001\000\002\001\001\000\002\001\001" +
    "\000\002\001\001\000\002\001\001\000\002\001\001\000" +
    "\002\001\001\000\002\001\001\000\002\001\001\000\002" +
    "\001\001\000\002\001\001\000\004\054\051\001\001\000" +
    "\002\001\001\000\002\001\001\000\002\001\001\000\004" +
    "\034\057\001\001\000\002\001\001\000\002\001\001\000" +
    "\002\001\001\000\002\001\001\000\006\015\114\037\113" +
    "\001\001\000\004\041\112\001\001\000\002\001\001\000" +
    "\002\001\001\000\002\001\001\000\002\001\001\000\004" +
    "\066\107\001\001\000\004\064\104\001\001\000\004\065" +
    "\072\001\001\000\012\042\077\047\074\052\100\053\075" +
    "\001\001\000\002\001\001\000\002\001\001\000\002\001" +
    "\001\000\002\001\001\000\002\001\001\000\002\001\001" +
    "\000\002\001\001\000\010\047\074\052\103\053\075\001" +
    "\001\000\002\001\001\000\012\042\105\047\074\052\100" +
    "\053\075\001\001\000\002\001\001\000\002\001\001\000" +
    "\012\042\110\047\074\052\100\053\075\001\001\000\002" +
    "\001\001\000\002\001\001\000\002\001\001\000\002\001" +
    "\001\000\010\016\126\030\127\046\124\001\001\000\002" +
    "\001\001\000\004\046\120\001\001\000\002\001\001\000" +
    "\004\067\122\001\001\000\002\001\001\000\002\001\001" +
    "\000\002\001\001\000\004\070\133\001\001\000\004\072" +
    "\131\001\001\000\006\030\130\046\124\001\001\000\002" +
    "\001\001\000\002\001\001\000\002\001\001\000\002\001" +
    "\001\000\002\001\001\000\004\071\135\001\001\000\012" +
    "\031\137\035\141\036\140\037\136\001\001\000\002\001" +
    "\001\000\006\032\150\047\147\001\001\000\002\001\001" +
    "\000\002\001\001\000\002\001\001\000\010\031\137\036" +
    "\144\037\136\001\001\000\002\001\001\000\002\001\001" +
    "\000\006\047\074\053\156\001\001\000\006\037\151\051" +
    "\152\001\001\000\002\001\001\000\002\001\001\000\002" +
    "\001\001\000\006\050\154\054\155\001\001\000\002\001" +
    "\001\000\002\001\001\000\002\001\001\000\002\001\001" +
    "\000\010\026\164\033\161\044\174\001\001\000\002\001" +
    "\001\000\004\060\172\001\001\000\002\001\001\000\004" +
    "\062\165\001\001\000\002\001\001\000\004\033\170\001" +
    "\001\000\002\001\001\000\002\001\001\000\002\001\001" +
    "\000\002\001\001\000\002\001\001\000\002\001\001\000" +
    "\002\001\001\000\006\005\203\037\204\001\001\000\006" +
    "\017\200\054\030\001\001\000\004\056\201\001\001\000" +
    "\002\001\001\000\002\001\001\000\006\007\205\020\206" +
    "\001\001\000\002\001\001\000\022\006\225\010\220\012" +
    "\012\013\217\014\227\022\221\023\216\024\007\001\001" +
    "\000\002\001\001\000\010\017\210\021\211\054\030\001" +
    "\001\000\002\001\001\000\004\057\212\001\001\000\002" +
    "\001\001\000\002\001\001\000\004\054\051\001\001\000" +
    "\002\001\001\000\002\001\001\000\002\001\001\000\002" +
    "\001\001\000\002\001\001\000\002\001\001\000\002\001" +
    "\001\000\002\001\001\000\002\001\001\000\002\001\001" +
    "\000\016\012\012\024\065\037\063\040\230\041\066\043" +
    "\062\001\001\000\006\015\231\037\113\001\001\000\010" +
    "\016\232\030\127\046\124\001\001\000\006\030\130\046" +
    "\124\001\001\000\002\001\001\000\004\011\236\001\001" +
    "\000\002\001\001\000\002\001\001\000\002\001\001\000" +
    "\004\011\241\001\001\000\002\001\001\000\002\001\001" +
    "\000\004\011\244\001\001\000\002\001\001\000\002\001" +
    "\001\000\004\011\247\001\001\000\002\001\001\000\002" +
    "\001\001" });

  /** Access to <code>reduce_goto</code> table. */
  public short[][] reduce_table() {return _reduce_table;}

  /** Instance of action encapsulation class. */
  protected CUP$parser$actions action_obj;

  /** Action encapsulation object initializer. */
  protected void init_actions()
    {
      action_obj = new CUP$parser$actions(this);
    }

  /** Invoke a user supplied parse action. */
  public java_cup.runtime.Symbol do_action(
    int                        act_num,
    java_cup.runtime.lr_parser parser,
    java.util.Stack            stack,
    int                        top)
    throws java.lang.Exception
  {
    /* call code in generated class */
    return action_obj.CUP$parser$do_action(act_num, parser, stack, top);
  }

  /** Indicates start state. */
  public int start_state() {return 0;}
  /** Indicates start production. */
  public int start_production() {return 0;}

  /** <code>EOF</code> Symbol index. */
  public int EOF_sym() {return 0;}

  /** <code>error</code> Symbol index. */
  public int error_sym() {return 1;}


  /** User initialization code. */
  public void user_init() throws java.lang.Exception
    {
 lexer.init(); 
    }

  /** Scan to get the next Symbol. */
  public java_cup.runtime.Symbol scan()
    throws java.lang.Exception
    {
 return lexer.next_token(); 
    }



  /* override error routines */

  public void report_fatal_error(
    String   message,
    Object   info)
    {
      done_parsing();
      lexer.emit_error(message);
      System.err.println("Can't recover from previous error(s), giving up.");
      System.exit(1);
    }

    public void report_error(String message, Object info)
    {
      lexer.emit_error(message);
    }

}

/** Cup generated class to encapsulate user supplied action code.*/
class CUP$parser$actions {


  /** helper routine to clone a new production part adding a given label */
  protected production_part add_lab(production_part part, String lab)
    throws internal_error
    {
      /* if there is no label, or this is an action, just return the original */
      if (lab == null || part.is_action()) return part;

      /* otherwise build a new one with the given label attached */
      return new symbol_part(((symbol_part)part).the_symbol(),lab);
    }

  /** max size of right hand side we will support */
  protected final int MAX_RHS = 200;

  /** array for accumulating right hand side parts */
  protected production_part[] rhs_parts = new production_part[MAX_RHS];

  /** where we are currently in building a right hand side */
  protected int rhs_pos = 0;

  /** start a new right hand side */
  protected void new_rhs() {rhs_pos = 0; }

  /** add a new right hand side part */
  protected void add_rhs_part(production_part part) throws java.lang.Exception
    {
      if (rhs_pos >= MAX_RHS)
	throw new Exception("Internal Error: Productions limited to " + 
			     MAX_RHS + " symbols and actions"); 

      rhs_parts[rhs_pos] = part;
      rhs_pos++;
    }

  /** string to build up multiple part names */
  protected String multipart_name = new String();

  /** append a new name segment to the accumulated multipart name */
  protected void append_multipart(String name)
    {
      String dot = "";

      /* if we aren't just starting out, put on a dot */
      if (multipart_name.length() != 0)  dot = ".";

      multipart_name = multipart_name.concat(dot + name);
    }

  /** table of declared symbols -- contains production parts indexed by name */
  protected Hashtable symbols = new Hashtable();

  /** table of just non terminals -- contains non_terminals indexed by name */
  protected Hashtable non_terms = new Hashtable();

  /** declared start non_terminal */
  protected non_terminal start_nt = null;

  /** left hand side non terminal of the current production */
  protected non_terminal lhs_nt;

  /** Current precedence number */
  int _cur_prec = 0;

  /** Current precedence side */
  int _cur_side = assoc.no_prec;

  /** update the precedences we are declaring */
  protected void update_precedence(int p) {
    _cur_side = p;
    _cur_prec++;
  }
  /** add relevant data to terminals */ 
  protected void add_precedence(String term) {
    if (term == null) {
      System.err.println("Unable to add precedence to nonexistent terminal");
    } else {
      symbol_part sp = (symbol_part)symbols.get(term);
      if (sp == null) {
	System.err.println("Could find terminal " + term + " while declaring precedence");
      } else {
	java_cup.symbol sym = sp.the_symbol();
	if (sym instanceof terminal) 
	  ((terminal)sym).set_precedence(_cur_side, _cur_prec);
	else System.err.println("Precedence declaration: Can't find terminal " + term);
      }
    }
  }

  private final parser parser;

  /** Constructor */
  CUP$parser$actions(parser parser) {
    this.parser = parser;
  }

  /** Method with the actual generated action code. */
  public final java_cup.runtime.Symbol CUP$parser$do_action(
    int                        CUP$parser$act_num,
    java_cup.runtime.lr_parser CUP$parser$parser,
    java.util.Stack            CUP$parser$stack,
    int                        CUP$parser$top)
    throws java.lang.Exception
    {
      /* Symbol object for return from actions */
      java_cup.runtime.Symbol CUP$parser$result;

      /* select the action based on the action number */
      switch (CUP$parser$act_num)
        {
          /*. . . . . . . . . . . . . . . . . . . .*/
          case 106: // empty ::= 
            {
              Object RESULT = null;

              CUP$parser$result = new java_cup.runtime.Symbol(29/*empty*/, ((java_cup.runtime.Symbol)CUP$parser$stack.elementAt(CUP$parser$top-0)).right, ((java_cup.runtime.Symbol)CUP$parser$stack.elementAt(CUP$parser$top-0)).right, RESULT);
            }
          return CUP$parser$result;

          /*. . . . . . . . . . . . . . . . . . . .*/
          case 105: // opt_semi ::= SEMI 
            {
              Object RESULT = null;

              CUP$parser$result = new java_cup.runtime.Symbol(7/*opt_semi*/, ((java_cup.runtime.Symbol)CUP$parser$stack.elementAt(CUP$parser$top-0)).left, ((java_cup.runtime.Symbol)CUP$parser$stack.elementAt(CUP$parser$top-0)).right, RESULT);
            }
          return CUP$parser$result;

          /*. . . . . . . . . . . . . . . . . . . .*/