+++ /dev/null
-
-package java_cup;
-
-/** This class represents one row (corresponding to one machine state) of the
- * parse action table.
- */
-public class parse_action_row {
-
- /*-----------------------------------------------------------*/
- /*--- Constructor(s) ----------------------------------------*/
- /*-----------------------------------------------------------*/
-
- /** Simple constructor. Note: this should not be used until the number of
- * terminals in the grammar has been established.
- */
- public parse_action_row()
- {
- /* make sure the size is set */
- if (_size <= 0 ) _size = terminal.number();
-
- /* allocate the array */
- under_term = new parse_action[size()];
-
- /* set each element to an error action */
- for (int i=0; i<_size; i++)
- under_term[i] = new parse_action();
- }
-
- /*-----------------------------------------------------------*/
- /*--- (Access to) Static (Class) Variables ------------------*/
- /*-----------------------------------------------------------*/
-
- /** Number of columns (terminals) in every row. */
- protected static int _size = 0;
-
- /** Number of columns (terminals) in every row. */
- public static int size() {return _size;}
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Table of reduction counts (reused by compute_default()). */
- protected static int reduction_count[] = null;
-
- /*-----------------------------------------------------------*/
- /*--- (Access to) Instance Variables ------------------------*/
- /*-----------------------------------------------------------*/
-
- /** Actual action entries for the row. */
- public parse_action under_term[];
-
- /*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .*/
-
- /** Default (reduce) action for this row. -1 will represent default
- * of error.
- */
- public int default_reduce;
-
- /*-----------------------------------------------------------*/
- /*--- General Methods ---------------------------------------*/
- /*-----------------------------------------------------------*/
-
- /** Compute the default (reduce) action for this row and store it in
- * default_reduce. In the case of non-zero default we will have the
- * effect of replacing all errors by that reduction. This may cause
- * us to do erroneous reduces, but will never cause us to shift past
- * the point of the error and never cause an incorrect parse. -1 will
- * be used to encode the fact that no reduction can be used as a
- * default (in which case error will be used).
- */
- public void compute_default()
- {
- int i, prod, max_prod, max_red;
-
- /* if we haven't allocated the count table, do so now */
- if (reduction_count == null)
- reduction_count = new int[production.number()];
-
- /* clear the reduction count table and maximums */
- for (i = 0; i < production.number(); i++)
- reduction_count[i] = 0;
- max_prod = -1;
- max_red = 0;
-
- /* walk down the row and look at the reduces */
- for (i = 0; i < size(); i++)
- if (under_term[i].kind() == parse_action.REDUCE)
- {
- /* count the reduce in the proper production slot and keep the
- max up to date */
- prod = ((reduce_action)under_term[i]).reduce_with().index();
- reduction_count[prod]++;
- if (reduction_count[prod] > max_red)
- {
- max_red = reduction_count[prod];
- max_prod = prod;
- }
- }
-
- /* record the max as the default (or -1 for not found) */
- default_reduce = max_prod;
- }
-
- /*-----------------------------------------------------------*/
-
-}
-