2 * Copyright (c) 1989 The Regents of the University of California.
5 * This code is derived from software contributed to Berkeley by
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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39 static char sccsid[] = "@(#)mkpar.c 5.3 (Berkeley) 1/20/91";
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
62 static action *add_reduce(action *, int, int);
63 static action *add_reductions(int, action *);
64 static void defreds(void);
65 static void find_final_state(void);
66 static void free_action_row(action *);
67 static action *get_shifts(int);
68 static action *parse_actions(int);
69 static void remove_conflicts(void);
70 static int sole_reduction(int);
71 static void total_conflicts(void);
72 static void unused_rules(void);
80 parser = NEW2(nstates, action *);
81 for (i = 0; i < nstates; i++)
82 parser[i] = parse_actions(i);
87 if (SRtotal + RRtotal > 0) total_conflicts();
93 parse_actions(int stateno)
97 actions = get_shifts(stateno);
98 actions = add_reductions(stateno, actions);
104 get_shifts(int stateno)
106 action *actions, *temp;
113 sp = shift_table[stateno];
117 for (i = sp->nshifts - 1; i >= 0; i--)
120 symbol = accessing_symbol[k];
124 temp->next = actions;
125 temp->symbol = symbol;
127 temp->prec = symbol_prec[symbol];
128 temp->action_code = SHIFT;
129 temp->assoc = symbol_assoc[symbol];
138 add_reductions(int stateno, action *actions)
141 int ruleno, tokensetsize;
144 tokensetsize = WORDSIZE(ntokens);
145 m = lookaheads[stateno];
146 n = lookaheads[stateno + 1];
147 for (i = m; i < n; i++)
149 ruleno = LAruleno[i];
150 rowp = LA + i * tokensetsize;
151 for (j = ntokens - 1; j >= 0; j--)
154 actions = add_reduce(actions, ruleno, j);
162 add_reduce(action *actions, int ruleno, int symbol)
164 action *temp, *prev, *next;
167 for (next = actions; next && next->symbol < symbol; next = next->next)
170 while (next && next->symbol == symbol && next->action_code == SHIFT)
176 while (next && next->symbol == symbol &&
177 next->action_code == REDUCE && next->number < ruleno)
185 temp->symbol = symbol;
186 temp->number = ruleno;
187 temp->prec = rprec[ruleno];
188 temp->action_code = REDUCE;
189 temp->assoc = rassoc[ruleno];
201 find_final_state(void)
210 for (i = p->nshifts - 1; i >= 0; --i)
212 final_state = tostate[i];
213 if (accessing_symbol[final_state] == goal) break;
224 rules_used = malloc(nrules*sizeof(short));
225 if (rules_used == 0) no_space();
227 for (i = 0; i < nrules; ++i)
230 for (i = 0; i < nstates; ++i)
232 for (p = parser[i]; p; p = p->next)
234 if (p->action_code == REDUCE && p->suppressed == 0)
235 rules_used[p->number] = 1;
240 for (i = 3; i < nrules; ++i)
241 if (!rules_used[i]) ++nunused;
245 warnx("1 rule never reduced");
247 warnx("%d rules never reduced", nunused);
253 remove_conflicts(void)
262 SRconflicts = NEW2(nstates, short);
263 RRconflicts = NEW2(nstates, short);
264 for (i = 0; i < nstates; i++)
269 for (p = parser[i]; p; p = p->next)
271 if (p->symbol != symbol)
276 else if (i == final_state && symbol == 0)
281 else if (pref->action_code == SHIFT)
283 if (pref->prec > 0 && p->prec > 0)
285 if (pref->prec < p->prec)
287 pref->suppressed = 2;
290 else if (pref->prec > p->prec)
294 else if (pref->assoc == LEFT)
296 pref->suppressed = 2;
299 else if (pref->assoc == RIGHT)
305 pref->suppressed = 2;
323 SRconflicts[i] = SRcount;
324 RRconflicts[i] = RRcount;
330 total_conflicts(void)
332 /* Warn if s/r != expect or if any r/r */
333 if ((SRtotal != SRexpect) || RRtotal)
336 warnx("1 shift/reduce conflict");
337 else if (SRtotal > 1)
338 warnx("%d shift/reduce conflicts", SRtotal);
342 warnx("1 reduce/reduce conflict");
343 else if (RRtotal > 1)
344 warnx("%d reduce/reduce conflicts", RRtotal);
349 sole_reduction(int stateno)
356 for (p = parser[stateno]; p; p = p->next)
358 if (p->action_code == SHIFT && p->suppressed == 0)
360 else if (p->action_code == REDUCE && p->suppressed == 0)
362 if (ruleno > 0 && p->number != ruleno)
381 defred = NEW2(nstates, short);
382 for (i = 0; i < nstates; i++)
383 defred[i] = sole_reduction(i);
387 free_action_row(action *p)
404 for (i = 0; i < nstates; i++)
405 free_action_row(parser[i]);