xref: /illumos-gate/usr/src/cmd/sgs/yacc/common/y3.c (revision 445784c00080f22524a1a4659cf8b7b2e1ad84d1)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /* Copyright (c) 1988 AT&T */
27 /* All Rights Reserved */
28 
29 #include "dextern.h"
30 
31 static void go2gen(int);
32 static void precftn(int, int, int);
33 static void wract(int);
34 static void wrstate(int);
35 static void wdef(wchar_t *, int);
36 static void wrmbchars(void);
37 	/* important local variables */
38 static int lastred; /* number of the last reduction of a state */
39 int *defact;
40 extern int *toklev;
41 extern int cwp;
42 
43 /* print the output for the states */
44 void
45 output(void)
46 {
47 	int i, k, c;
48 	WSET *u, *v;
49 
50 	(void) fprintf(ftable, "static YYCONST yytabelem yyexca[] ={\n");
51 
52 	SLOOP(i) { /* output the stuff for state i */
53 		nolook = !(tystate[i] == MUSTLOOKAHEAD);
54 		closure(i);
55 		/* output actions */
56 		nolook = 1;
57 		aryfil(temp1, ntoksz+nnontersz+1, 0);
58 		WSLOOP(wsets, u) {
59 			c = *(u->pitem);
60 			if (c > 1 && c < NTBASE && temp1[c] == 0) {
61 				WSLOOP(u, v) {
62 					if (c == *(v->pitem))
63 						putitem(v->pitem + 1,
64 						    (LOOKSETS *)0);
65 				}
66 				temp1[c] = state(c);
67 			} else if (c > NTBASE &&
68 			    temp1[(c -= NTBASE) + ntokens] == 0) {
69 				temp1[c + ntokens] = amem[indgo[i] + c];
70 			}
71 		}
72 		if (i == 1)
73 			temp1[1] = ACCEPTCODE;
74 		/* now, we have the shifts; look at the reductions */
75 		lastred = 0;
76 		WSLOOP(wsets, u) {
77 			c = *(u->pitem);
78 			if (c <= 0) { /* reduction */
79 				lastred = -c;
80 				TLOOP(k) {
81 					if (BIT(u->ws.lset, k)) {
82 						if (temp1[k] == 0)
83 							temp1[k] = c;
84 						else if (temp1[k] < 0) {
85 							/*
86 							 * reduce/reduce
87 							 * conflict
88 							 */
89 							/* BEGIN CSTYLED */
90 							if (foutput != NULL)
91 					(void) fprintf(foutput,
92 				"\n%d: reduce/reduce conflict"
93 				" (red'ns %d and %d ) on %ws",
94 							i, -temp1[k],
95 							lastred, symnam(k));
96 						    if (-temp1[k] > lastred)
97 							temp1[k] = -lastred;
98 						    ++zzrrconf;
99 							/* END CSTYLED */
100 						} else
101 							/*
102 							 * potentia
103 							 * shift/reduce
104 							 * conflict.
105 							 */
106 							precftn(lastred, k, i);
107 					}
108 				}
109 			}
110 		}
111 		wract(i);
112 	}
113 
114 	(void) fprintf(ftable, "\t};\n");
115 	wdef(L"YYNPROD", nprod);
116 	if (nmbchars > 0) {
117 		wrmbchars();
118 	}
119 }
120 
121 static int pkdebug = 0;
122 int
123 apack(int *p, int n)
124 {
125 	/* pack state i from temp1 into amem */
126 	int off;
127 	int *pp, *qq;
128 	int *q, *rr;
129 	int diff;
130 
131 	/*
132 	 * we don't need to worry about checking because we
133 	 * we will only look up entries known to be there...
134 	 */
135 
136 	/* eliminate leading and trailing 0's */
137 
138 	q = p + n;
139 	for (pp = p, off = 0; *pp == 0 && pp <= q; ++pp, --off)
140 		/* NULL */;
141 	if (pp > q)
142 		return (0);  /* no actions */
143 	p = pp;
144 
145 	/* now, find a place for the elements from p to q, inclusive */
146 	/* for( rr=amem; rr<=r; ++rr,++off ){ */  /* try rr */
147 	rr = amem;
148 	for (; ; ++rr, ++off) {
149 		while (rr >= &amem[new_actsize-1])
150 			exp_act(&rr);
151 		qq = rr;
152 		for (pp = p; pp <= q; ++pp, ++qq) {
153 			if (*pp) {
154 				diff = qq - rr;
155 				while (qq >= &amem[new_actsize-1]) {
156 					exp_act(&rr);
157 					qq = diff + rr;
158 				}
159 				if (*pp != *qq && *qq != 0)
160 					goto nextk;
161 			}
162 		}
163 
164 		/* we have found an acceptable k */
165 
166 		if (pkdebug && foutput != NULL)
167 			(void) fprintf(foutput,
168 			    "off = %d, k = %" PRIdPTR "\n", off, rr-amem);
169 
170 		qq = rr;
171 		for (pp = p; pp <= q; ++pp, ++qq) {
172 			if (*pp) {
173 				diff = qq - rr;
174 				while (qq >= &amem[new_actsize-1]) {
175 					exp_act(&rr);
176 					qq = diff + rr;
177 				}
178 				if (qq > memp)
179 					memp = qq;
180 				*qq = *pp;
181 			}
182 		}
183 		if (pkdebug && foutput != NULL) {
184 			for (pp = amem; pp <= memp; pp += 10) {
185 				(void) fprintf(foutput, "\t");
186 				for (qq = pp; qq <= pp + 9; ++qq)
187 					(void) fprintf(foutput, "%d ", *qq);
188 				(void) fprintf(foutput, "\n");
189 			}
190 		}
191 		return (off);
192 		nextk:;
193 	}
194 	/* error("no space in action table" ); */
195 	/* NOTREACHED */
196 }
197 
198 void
199 go2out(void)
200 {
201 	/* output the gotos for the nontermninals */
202 	int i, j, k, best, count, cbest, times;
203 
204 	(void) fprintf(ftemp, "$\n");  /* mark begining of gotos */
205 
206 	for (i = 1; i <= nnonter; ++i) {
207 		go2gen(i);
208 		/* find the best one to make default */
209 		best = -1;
210 		times = 0;
211 		for (j = 0; j < nstate; ++j) { /* is j the most frequent */
212 			if (tystate[j] == 0)
213 				continue;
214 			if (tystate[j] == best)
215 				continue;
216 			/* is tystate[j] the most frequent */
217 			count = 0;
218 			cbest = tystate[j];
219 			for (k = j; k < nstate; ++k)
220 				if (tystate[k] == cbest)
221 					++count;
222 			if (count > times) {
223 				best = cbest;
224 				times = count;
225 			}
226 		}
227 
228 		/* best is now the default entry */
229 		zzgobest += (times-1);
230 		for (j = 0; j < nstate; ++j) {
231 			if (tystate[j] != 0 && tystate[j] != best) {
232 				(void) fprintf(ftemp, "%d,%d,", j, tystate[j]);
233 				zzgoent += 1;
234 			}
235 		}
236 
237 		/* now, the default */
238 
239 		zzgoent += 1;
240 		(void) fprintf(ftemp, "%d\n", best);
241 
242 	}
243 }
244 
245 static int g2debug = 0;
246 static void
247 go2gen(int c)
248 {
249 	/* output the gotos for nonterminal c */
250 	int i, work, cc;
251 	ITEM *p, *q;
252 
253 	/* first, find nonterminals with gotos on c */
254 	aryfil(temp1, nnonter + 1, 0);
255 	temp1[c] = 1;
256 
257 	work = 1;
258 	while (work) {
259 		work = 0;
260 		PLOOP(0, i) {
261 			if ((cc = prdptr[i][1] - NTBASE) >= 0) {
262 				/* cc is a nonterminal */
263 				if (temp1[cc] != 0) {
264 					/*
265 					 * cc has a goto on c
266 					 * thus, the left side of
267 					 * production i does too.
268 					 */
269 					cc = *prdptr[i] - NTBASE;
270 					if (temp1[cc] == 0) {
271 						work = 1;
272 						temp1[cc] = 1;
273 					}
274 				}
275 			}
276 		}
277 	}
278 
279 	/* now, we have temp1[c] = 1 if a goto on c in closure of cc */
280 
281 	if (g2debug && foutput != NULL) {
282 		(void) fprintf(foutput, "%ws: gotos on ",
283 		    nontrst[c].name);
284 		NTLOOP(i) if (temp1[i])
285 			(void) fprintf(foutput, "%ws ", nontrst[i].name);
286 		(void) fprintf(foutput, "\n");
287 	}
288 
289 	/* now, go through and put gotos into tystate */
290 	aryfil(tystate, nstate, 0);
291 	SLOOP(i) {
292 		ITMLOOP(i, p, q) {
293 			if ((cc = *p->pitem) >= NTBASE) {
294 				if (temp1[cc -= NTBASE]) {
295 					/* goto on c is possible */
296 					tystate[i] = amem[indgo[i] + c];
297 					break;
298 				}
299 			}
300 		}
301 	}
302 }
303 
304 /* decide a shift/reduce conflict by precedence.  */
305 static void
306 precftn(int r, int t, int s)
307 {
308 
309 	/*
310 	 * r is a rule number, t a token number
311 	 * the conflict is in state s
312 	 * temp1[t] is changed to reflect the action
313 	 */
314 
315 	int lp, lt, action;
316 
317 	lp = levprd[r];
318 	lt = toklev[t];
319 	if (PLEVEL(lt) == 0 || PLEVEL(lp) == 0) {
320 		/* conflict */
321 		if (foutput != NULL)
322 			(void) fprintf(foutput,
323 			    "\n%d: shift/reduce conflict"
324 			    " (shift %d, red'n %d) on %ws",
325 			    s, temp1[t], r, symnam(t));
326 		++zzsrconf;
327 		return;
328 	}
329 	if (PLEVEL(lt) == PLEVEL(lp))
330 		action = ASSOC(lt) & ~04;
331 	else if (PLEVEL(lt) > PLEVEL(lp))
332 		action = RASC;  /* shift */
333 	else
334 		action = LASC;  /* reduce */
335 
336 	switch (action) {
337 	case BASC:  /* error action */
338 		temp1[t] = ERRCODE;
339 		return;
340 	case LASC:  /* reduce */
341 		temp1[t] = -r;
342 		return;
343 	}
344 }
345 
346 static void
347 wract(int i)
348 {
349 	/* output state i */
350 	/* temp1 has the actions, lastred the default */
351 	int p, p0, p1;
352 	int ntimes, tred, count, j;
353 	int flag;
354 
355 	/* find the best choice for lastred */
356 
357 	lastred = 0;
358 	ntimes = 0;
359 	TLOOP(j) {
360 		if (temp1[j] >= 0)
361 			continue;
362 		if (temp1[j] + lastred == 0)
363 			continue;
364 		/* count the number of appearances of temp1[j] */
365 		count = 0;
366 		tred = -temp1[j];
367 		levprd[tred] |= REDFLAG;
368 		TLOOP(p) {
369 			if (temp1[p] + tred == 0)
370 				++count;
371 		}
372 		if (count > ntimes) {
373 			lastred = tred;
374 			ntimes = count;
375 		}
376 	}
377 
378 	/*
379 	 * for error recovery, arrange that, if there is a shift on the
380 	 * error recovery token, `error', that the default be the error action
381 	 */
382 	if (temp1[2] > 0)
383 		lastred = 0;
384 
385 	/* clear out entries in temp1 which equal lastred */
386 	TLOOP(p) {
387 		if (temp1[p] + lastred == 0)
388 			temp1[p] = 0;
389 	}
390 
391 	wrstate(i);
392 	defact[i] = lastred;
393 
394 	flag = 0;
395 	TLOOP(p0) {
396 		if ((p1 = temp1[p0]) != 0) {
397 			if (p1 < 0) {
398 				p1 = -p1;
399 				goto exc;
400 			} else if (p1 == ACCEPTCODE) {
401 				p1 = -1;
402 				goto exc;
403 			} else if (p1 == ERRCODE) {
404 				p1 = 0;
405 				goto exc;
406 			exc:
407 				if (flag++ == 0)
408 					(void) fprintf(ftable, "-1, %d,\n", i);
409 				(void) fprintf(ftable,
410 				    "\t%d, %d,\n", tokset[p0].value, p1);
411 				++zzexcp;
412 			} else {
413 				(void) fprintf(ftemp,
414 				    "%d,%d,", tokset[p0].value, p1);
415 				++zzacent;
416 			}
417 		}
418 	}
419 	if (flag) {
420 		defact[i] = -2;
421 		(void) fprintf(ftable, "\t-2, %d,\n", lastred);
422 	}
423 	(void) fprintf(ftemp, "\n");
424 }
425 
426 static void
427 wrstate(int i)
428 {
429 	/* writes state i */
430 	int j0, j1;
431 	register ITEM *pp, *qq;
432 	register WSET *u;
433 
434 	if (foutput == NULL)
435 		return;
436 	(void) fprintf(foutput, "\nstate %d\n", i);
437 	ITMLOOP(i, pp, qq) {
438 		(void) fprintf(foutput, "\t%ws\n", writem(pp->pitem));
439 	}
440 	if (tystate[i] == MUSTLOOKAHEAD) {
441 		/* print out empty productions in closure */
442 		WSLOOP(wsets + (pstate[i + 1] - pstate[i]), u) {
443 			if (*(u->pitem) < 0)
444 				(void) fprintf(foutput,
445 				    "\t%ws\n", writem(u->pitem));
446 		}
447 	}
448 
449 	/* check for state equal to another */
450 	TLOOP(j0) if ((j1 = temp1[j0]) != 0) {
451 		(void) fprintf(foutput, "\n\t%ws  ", symnam(j0));
452 		if (j1 > 0) { /* shift, error, or accept */
453 			if (j1 == ACCEPTCODE)
454 				(void) fprintf(foutput,  "accept");
455 			else if (j1 == ERRCODE)
456 				(void) fprintf(foutput, "error");
457 			else
458 				(void) fprintf(foutput, "shift %d", j1);
459 		}
460 		else
461 			(void) fprintf(foutput, "reduce %d", -j1);
462 	}
463 
464 	/* output the final production */
465 	if (lastred)
466 		(void) fprintf(foutput, "\n\t.  reduce %d\n\n", lastred);
467 	else
468 		(void) fprintf(foutput, "\n\t.  error\n\n");
469 
470 	/* now, output nonterminal actions */
471 	j1 = ntokens;
472 	for (j0 = 1; j0 <= nnonter; ++j0) {
473 		if (temp1[++j1])
474 			(void) fprintf(foutput,
475 			    "\t%ws  goto %d\n",
476 			    symnam(j0 + NTBASE), temp1[j1]);
477 	}
478 }
479 
480 static void
481 wdef(wchar_t *s, int n)
482 {
483 	/* output a definition of s to the value n */
484 	(void) fprintf(ftable, "# define %ws %d\n", s, n);
485 }
486 
487 void
488 warray(wchar_t *s, int *v, int n)
489 {
490 	int i;
491 	(void) fprintf(ftable, "static YYCONST yytabelem %ws[]={\n", s);
492 	for (i = 0; i < n; ) {
493 		if (i % 10 == 0)
494 			(void) fprintf(ftable, "\n");
495 		(void) fprintf(ftable, "%6d", v[i]);
496 		if (++i == n)
497 			(void) fprintf(ftable, " };\n");
498 		else
499 			(void) fprintf(ftable, ",");
500 	}
501 }
502 
503 void
504 hideprod(void)
505 {
506 	/*
507 	 * in order to free up the mem and amem arrays for the optimizer,
508 	 * and still be able to output yyr1, etc., after the sizes of
509 	 * the action array is known, we hide the nonterminals
510 	 * derived by productions in levprd.
511 	 */
512 
513 	int i, j;
514 
515 	j = 0;
516 	levprd[0] = 0;
517 	PLOOP(1, i) {
518 		if (!(levprd[i] & REDFLAG)) {
519 			++j;
520 			if (foutput != NULL) {
521 				(void) fprintf(foutput,
522 				    "Rule not reduced:   %ws\n",
523 				    writem(prdptr[i]));
524 			}
525 		}
526 		levprd[i] = *prdptr[i] - NTBASE;
527 	}
528 	if (j)
529 /*
530  * TRANSLATION_NOTE  -- This is a message from yacc.
531  *	Check how 'reduced' is translated in yacc man page/document.
532  */
533 		(void) fprintf(stderr,
534 		    gettext("%d rules never reduced\n"),
535 		    j);
536 }
537 
538 
539 static int
540 cmpmbchars(MBCLIT *p, MBCLIT *q)
541 {
542 	/* Compare two MBLITs. */
543 	return ((p->character) - (q->character));
544 }
545 
546 static void
547 wrmbchars(void)
548 {
549 	int i;
550 	wdef(L"YYNMBCHARS", nmbchars);
551 	qsort(mbchars, nmbchars, sizeof (*mbchars),
552 	    (int (*)(const void *, const void *))cmpmbchars);
553 	(void) fprintf(ftable,
554 	    "static struct{\n\twchar_t character;"
555 	    "\n\tint tvalue;\n}yymbchars[YYNMBCHARS]={\n");
556 	for (i = 0; i < nmbchars; ++i) {
557 		(void) fprintf(ftable, "\t{%#x,%d}",
558 		    (int)mbchars[i].character, mbchars[i].tvalue);
559 		if (i < nmbchars - 1) {
560 			/* Not the last. */
561 			(void) fprintf(ftable, ",\n");
562 		}
563 	}
564 	(void) fprintf(ftable, "\n};\n");
565 }
566