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3877f72ba2
nlookaheads is a new member. Adjust all users. * src/lalr.h (nlookaheads): Remove this orphan declaration. * src/lalr.c (initialize_lookaheads): Set nlookaheads for each state.
78 lines
2.5 KiB
C
78 lines
2.5 KiB
C
/* Compute look-ahead criteria for bison,
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Copyright 1984, 1986, 1989, 2000 Free Software Foundation, Inc.
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This file is part of Bison, the GNU Compiler Compiler.
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Bison is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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Bison is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with Bison; see the file COPYING. If not, write to
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the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#ifndef LALR_H_
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# define LALR_H_
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/* Import the definition of CORE, SHIFTS and REDUCTIONS. */
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# include "state.h"
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/* Compute how to make the finite state machine deterministic; find
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which rules need lookahead in each state, and which lookahead
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tokens they accept. */
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void lalr PARAMS ((void));
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/* lalr() builds these data structures. */
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/* GOTO_MAP, FROM_STATE and TO_STATE -- record each shift transition
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which accepts a variable (a nonterminal).
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FROM_STATE[T] -- state number which a transition leads from.
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TO_STATE[T] -- state number it leads to.
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All the transitions that accept a particular variable are grouped
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together and GOTO_MAP[I - NTOKENS] is the index in FROM_STATE and
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TO_STATE of the first of them. */
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extern short *goto_map;
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extern short *from_state;
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extern short *to_state;
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/* LARULENO is a vector which records the rules that need lookahead in
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various states. The elements of LARULENO that apply to state S are
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those from LOOKAHEADS[S] through LOOKAHEADS[S+1]-1. Each element
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of LARULENO is a rule number.
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If LR is the length of LAruleno, then a number from 0 to LR-1 can
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specify both a rule and a state where the rule might be applied.
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*/
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extern short *LAruleno;
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/* LA is a lr by ntokens matrix of bits. LA[l, i] is 1 if the rule
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LAruleno[l] is applicable in the appropriate state when the next
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token is symbol i. If LA[l, i] and LA[l, j] are both 1 for i != j,
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it is a conflict. */
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extern unsigned *LA;
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#define LA(Rule) (LA + (Rule) * tokensetsize)
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/* All the states, indexed by the state number. */
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extern state_t **state_table;
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extern int tokensetsize;
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#endif /* !LALR_H_ */
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