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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
4 */
5
6#include <ctype.h>
7#include <errno.h>
8#include <stdio.h>
9#include <stdlib.h>
10#include <string.h>
11
12#include "lkc.h"
13
14#define DEBUG_EXPR 0
15
16static struct expr *expr_eliminate_yn(struct expr *e);
17
18struct expr *expr_alloc_symbol(struct symbol *sym)
19{
20 struct expr *e = xcalloc(1, sizeof(*e));
21 e->type = E_SYMBOL;
22 e->left.sym = sym;
23 return e;
24}
25
26struct expr *expr_alloc_one(enum expr_type type, struct expr *ce)
27{
28 struct expr *e = xcalloc(1, sizeof(*e));
29 e->type = type;
30 e->left.expr = ce;
31 return e;
32}
33
34struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2)
35{
36 struct expr *e = xcalloc(1, sizeof(*e));
37 e->type = type;
38 e->left.expr = e1;
39 e->right.expr = e2;
40 return e;
41}
42
43struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2)
44{
45 struct expr *e = xcalloc(1, sizeof(*e));
46 e->type = type;
47 e->left.sym = s1;
48 e->right.sym = s2;
49 return e;
50}
51
52struct expr *expr_alloc_and(struct expr *e1, struct expr *e2)
53{
54 if (!e1)
55 return e2;
56 return e2 ? expr_alloc_two(E_AND, e1, e2) : e1;
57}
58
59struct expr *expr_alloc_or(struct expr *e1, struct expr *e2)
60{
61 if (!e1)
62 return e2;
63 return e2 ? expr_alloc_two(E_OR, e1, e2) : e1;
64}
65
66struct expr *expr_copy(const struct expr *org)
67{
68 struct expr *e;
69
70 if (!org)
71 return NULL;
72
73 e = xmalloc(sizeof(*org));
74 memcpy(e, org, sizeof(*org));
75 switch (org->type) {
76 case E_SYMBOL:
77 e->left = org->left;
78 break;
79 case E_NOT:
80 e->left.expr = expr_copy(org->left.expr);
81 break;
82 case E_EQUAL:
83 case E_GEQ:
84 case E_GTH:
85 case E_LEQ:
86 case E_LTH:
87 case E_UNEQUAL:
88 e->left.sym = org->left.sym;
89 e->right.sym = org->right.sym;
90 break;
91 case E_AND:
92 case E_OR:
93 case E_LIST:
94 e->left.expr = expr_copy(org->left.expr);
95 e->right.expr = expr_copy(org->right.expr);
96 break;
97 default:
98 fprintf(stderr, "can't copy type %d\n", e->type);
99 free(e);
100 e = NULL;
101 break;
102 }
103
104 return e;
105}
106
107void expr_free(struct expr *e)
108{
109 if (!e)
110 return;
111
112 switch (e->type) {
113 case E_SYMBOL:
114 break;
115 case E_NOT:
116 expr_free(e->left.expr);
117 break;
118 case E_EQUAL:
119 case E_GEQ:
120 case E_GTH:
121 case E_LEQ:
122 case E_LTH:
123 case E_UNEQUAL:
124 break;
125 case E_OR:
126 case E_AND:
127 expr_free(e->left.expr);
128 expr_free(e->right.expr);
129 break;
130 default:
131 fprintf(stderr, "how to free type %d?\n", e->type);
132 break;
133 }
134 free(e);
135}
136
137static int trans_count;
138
139#define e1 (*ep1)
140#define e2 (*ep2)
141
142/*
143 * expr_eliminate_eq() helper.
144 *
145 * Walks the two expression trees given in 'ep1' and 'ep2'. Any node that does
146 * not have type 'type' (E_OR/E_AND) is considered a leaf, and is compared
147 * against all other leaves. Two equal leaves are both replaced with either 'y'
148 * or 'n' as appropriate for 'type', to be eliminated later.
149 */
150static void __expr_eliminate_eq(enum expr_type type, struct expr **ep1, struct expr **ep2)
151{
152 /* Recurse down to leaves */
153
154 if (e1->type == type) {
155 __expr_eliminate_eq(type, &e1->left.expr, &e2);
156 __expr_eliminate_eq(type, &e1->right.expr, &e2);
157 return;
158 }
159 if (e2->type == type) {
160 __expr_eliminate_eq(type, &e1, &e2->left.expr);
161 __expr_eliminate_eq(type, &e1, &e2->right.expr);
162 return;
163 }
164
165 /* e1 and e2 are leaves. Compare them. */
166
167 if (e1->type == E_SYMBOL && e2->type == E_SYMBOL &&
168 e1->left.sym == e2->left.sym &&
169 (e1->left.sym == &symbol_yes || e1->left.sym == &symbol_no))
170 return;
171 if (!expr_eq(e1, e2))
172 return;
173
174 /* e1 and e2 are equal leaves. Prepare them for elimination. */
175
176 trans_count++;
177 expr_free(e1); expr_free(e2);
178 switch (type) {
179 case E_OR:
180 e1 = expr_alloc_symbol(&symbol_no);
181 e2 = expr_alloc_symbol(&symbol_no);
182 break;
183 case E_AND:
184 e1 = expr_alloc_symbol(&symbol_yes);
185 e2 = expr_alloc_symbol(&symbol_yes);
186 break;
187 default:
188 ;
189 }
190}
191
192/*
193 * Rewrites the expressions 'ep1' and 'ep2' to remove operands common to both.
194 * Example reductions:
195 *
196 * ep1: A && B -> ep1: y
197 * ep2: A && B && C -> ep2: C
198 *
199 * ep1: A || B -> ep1: n
200 * ep2: A || B || C -> ep2: C
201 *
202 * ep1: A && (B && FOO) -> ep1: FOO
203 * ep2: (BAR && B) && A -> ep2: BAR
204 *
205 * ep1: A && (B || C) -> ep1: y
206 * ep2: (C || B) && A -> ep2: y
207 *
208 * Comparisons are done between all operands at the same "level" of && or ||.
209 * For example, in the expression 'e1 && (e2 || e3) && (e4 || e5)', the
210 * following operands will be compared:
211 *
212 * - 'e1', 'e2 || e3', and 'e4 || e5', against each other
213 * - e2 against e3
214 * - e4 against e5
215 *
216 * Parentheses are irrelevant within a single level. 'e1 && (e2 && e3)' and
217 * '(e1 && e2) && e3' are both a single level.
218 *
219 * See __expr_eliminate_eq() as well.
220 */
221void expr_eliminate_eq(struct expr **ep1, struct expr **ep2)
222{
223 if (!e1 || !e2)
224 return;
225 switch (e1->type) {
226 case E_OR:
227 case E_AND:
228 __expr_eliminate_eq(e1->type, ep1, ep2);
229 default:
230 ;
231 }
232 if (e1->type != e2->type) switch (e2->type) {
233 case E_OR:
234 case E_AND:
235 __expr_eliminate_eq(e2->type, ep1, ep2);
236 default:
237 ;
238 }
239 e1 = expr_eliminate_yn(e1);
240 e2 = expr_eliminate_yn(e2);
241}
242
243#undef e1
244#undef e2
245
246/*
247 * Returns true if 'e1' and 'e2' are equal, after minor simplification. Two
248 * &&/|| expressions are considered equal if every operand in one expression
249 * equals some operand in the other (operands do not need to appear in the same
250 * order), recursively.
251 */
252int expr_eq(struct expr *e1, struct expr *e2)
253{
254 int res, old_count;
255
256 /*
257 * A NULL expr is taken to be yes, but there's also a different way to
258 * represent yes. expr_is_yes() checks for either representation.
259 */
260 if (!e1 || !e2)
261 return expr_is_yes(e1) && expr_is_yes(e2);
262
263 if (e1->type != e2->type)
264 return 0;
265 switch (e1->type) {
266 case E_EQUAL:
267 case E_GEQ:
268 case E_GTH:
269 case E_LEQ:
270 case E_LTH:
271 case E_UNEQUAL:
272 return e1->left.sym == e2->left.sym && e1->right.sym == e2->right.sym;
273 case E_SYMBOL:
274 return e1->left.sym == e2->left.sym;
275 case E_NOT:
276 return expr_eq(e1->left.expr, e2->left.expr);
277 case E_AND:
278 case E_OR:
279 e1 = expr_copy(e1);
280 e2 = expr_copy(e2);
281 old_count = trans_count;
282 expr_eliminate_eq(&e1, &e2);
283 res = (e1->type == E_SYMBOL && e2->type == E_SYMBOL &&
284 e1->left.sym == e2->left.sym);
285 expr_free(e1);
286 expr_free(e2);
287 trans_count = old_count;
288 return res;
289 case E_LIST:
290 case E_RANGE:
291 case E_NONE:
292 /* panic */;
293 }
294
295 if (DEBUG_EXPR) {
296 expr_fprint(e1, stdout);
297 printf(" = ");
298 expr_fprint(e2, stdout);
299 printf(" ?\n");
300 }
301
302 return 0;
303}
304
305/*
306 * Recursively performs the following simplifications in-place (as well as the
307 * corresponding simplifications with swapped operands):
308 *
309 * expr && n -> n
310 * expr && y -> expr
311 * expr || n -> expr
312 * expr || y -> y
313 *
314 * Returns the optimized expression.
315 */
316static struct expr *expr_eliminate_yn(struct expr *e)
317{
318 struct expr *tmp;
319
320 if (e) switch (e->type) {
321 case E_AND:
322 e->left.expr = expr_eliminate_yn(e->left.expr);
323 e->right.expr = expr_eliminate_yn(e->right.expr);
324 if (e->left.expr->type == E_SYMBOL) {
325 if (e->left.expr->left.sym == &symbol_no) {
326 expr_free(e->left.expr);
327 expr_free(e->right.expr);
328 e->type = E_SYMBOL;
329 e->left.sym = &symbol_no;
330 e->right.expr = NULL;
331 return e;
332 } else if (e->left.expr->left.sym == &symbol_yes) {
333 free(e->left.expr);
334 tmp = e->right.expr;
335 *e = *(e->right.expr);
336 free(tmp);
337 return e;
338 }
339 }
340 if (e->right.expr->type == E_SYMBOL) {
341 if (e->right.expr->left.sym == &symbol_no) {
342 expr_free(e->left.expr);
343 expr_free(e->right.expr);
344 e->type = E_SYMBOL;
345 e->left.sym = &symbol_no;
346 e->right.expr = NULL;
347 return e;
348 } else if (e->right.expr->left.sym == &symbol_yes) {
349 free(e->right.expr);
350 tmp = e->left.expr;
351 *e = *(e->left.expr);
352 free(tmp);
353 return e;
354 }
355 }
356 break;
357 case E_OR:
358 e->left.expr = expr_eliminate_yn(e->left.expr);
359 e->right.expr = expr_eliminate_yn(e->right.expr);
360 if (e->left.expr->type == E_SYMBOL) {
361 if (e->left.expr->left.sym == &symbol_no) {
362 free(e->left.expr);
363 tmp = e->right.expr;
364 *e = *(e->right.expr);
365 free(tmp);
366 return e;
367 } else if (e->left.expr->left.sym == &symbol_yes) {
368 expr_free(e->left.expr);
369 expr_free(e->right.expr);
370 e->type = E_SYMBOL;
371 e->left.sym = &symbol_yes;
372 e->right.expr = NULL;
373 return e;
374 }
375 }
376 if (e->right.expr->type == E_SYMBOL) {
377 if (e->right.expr->left.sym == &symbol_no) {
378 free(e->right.expr);
379 tmp = e->left.expr;
380 *e = *(e->left.expr);
381 free(tmp);
382 return e;
383 } else if (e->right.expr->left.sym == &symbol_yes) {
384 expr_free(e->left.expr);
385 expr_free(e->right.expr);
386 e->type = E_SYMBOL;
387 e->left.sym = &symbol_yes;
388 e->right.expr = NULL;
389 return e;
390 }
391 }
392 break;
393 default:
394 ;
395 }
396 return e;
397}
398
399/*
400 * bool FOO!=n => FOO
401 */
402struct expr *expr_trans_bool(struct expr *e)
403{
404 if (!e)
405 return NULL;
406 switch (e->type) {
407 case E_AND:
408 case E_OR:
409 case E_NOT:
410 e->left.expr = expr_trans_bool(e->left.expr);
411 e->right.expr = expr_trans_bool(e->right.expr);
412 break;
413 case E_UNEQUAL:
414 // FOO!=n -> FOO
415 if (e->left.sym->type == S_TRISTATE) {
416 if (e->right.sym == &symbol_no) {
417 e->type = E_SYMBOL;
418 e->right.sym = NULL;
419 }
420 }
421 break;
422 default:
423 ;
424 }
425 return e;
426}
427
428/*
429 * e1 || e2 -> ?
430 */
431static struct expr *expr_join_or(struct expr *e1, struct expr *e2)
432{
433 struct expr *tmp;
434 struct symbol *sym1, *sym2;
435
436 if (expr_eq(e1, e2))
437 return expr_copy(e1);
438 if (e1->type != E_EQUAL && e1->type != E_UNEQUAL && e1->type != E_SYMBOL && e1->type != E_NOT)
439 return NULL;
440 if (e2->type != E_EQUAL && e2->type != E_UNEQUAL && e2->type != E_SYMBOL && e2->type != E_NOT)
441 return NULL;
442 if (e1->type == E_NOT) {
443 tmp = e1->left.expr;
444 if (tmp->type != E_EQUAL && tmp->type != E_UNEQUAL && tmp->type != E_SYMBOL)
445 return NULL;
446 sym1 = tmp->left.sym;
447 } else
448 sym1 = e1->left.sym;
449 if (e2->type == E_NOT) {
450 if (e2->left.expr->type != E_SYMBOL)
451 return NULL;
452 sym2 = e2->left.expr->left.sym;
453 } else
454 sym2 = e2->left.sym;
455 if (sym1 != sym2)
456 return NULL;
457 if (sym1->type != S_BOOLEAN && sym1->type != S_TRISTATE)
458 return NULL;
459 if (sym1->type == S_TRISTATE) {
460 if (e1->type == E_EQUAL && e2->type == E_EQUAL &&
461 ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_mod) ||
462 (e1->right.sym == &symbol_mod && e2->right.sym == &symbol_yes))) {
463 // (a='y') || (a='m') -> (a!='n')
464 return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_no);
465 }
466 if (e1->type == E_EQUAL && e2->type == E_EQUAL &&
467 ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_no) ||
468 (e1->right.sym == &symbol_no && e2->right.sym == &symbol_yes))) {
469 // (a='y') || (a='n') -> (a!='m')
470 return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_mod);
471 }
472 if (e1->type == E_EQUAL && e2->type == E_EQUAL &&
473 ((e1->right.sym == &symbol_mod && e2->right.sym == &symbol_no) ||
474 (e1->right.sym == &symbol_no && e2->right.sym == &symbol_mod))) {
475 // (a='m') || (a='n') -> (a!='y')
476 return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_yes);
477 }
478 }
479 if (sym1->type == S_BOOLEAN && sym1 == sym2) {
480 if ((e1->type == E_NOT && e1->left.expr->type == E_SYMBOL && e2->type == E_SYMBOL) ||
481 (e2->type == E_NOT && e2->left.expr->type == E_SYMBOL && e1->type == E_SYMBOL))
482 return expr_alloc_symbol(&symbol_yes);
483 }
484
485 if (DEBUG_EXPR) {
486 printf("optimize (");
487 expr_fprint(e1, stdout);
488 printf(") || (");
489 expr_fprint(e2, stdout);
490 printf(")?\n");
491 }
492 return NULL;
493}
494
495static struct expr *expr_join_and(struct expr *e1, struct expr *e2)
496{
497 struct expr *tmp;
498 struct symbol *sym1, *sym2;
499
500 if (expr_eq(e1, e2))
501 return expr_copy(e1);
502 if (e1->type != E_EQUAL && e1->type != E_UNEQUAL && e1->type != E_SYMBOL && e1->type != E_NOT)
503 return NULL;
504 if (e2->type != E_EQUAL && e2->type != E_UNEQUAL && e2->type != E_SYMBOL && e2->type != E_NOT)
505 return NULL;
506 if (e1->type == E_NOT) {
507 tmp = e1->left.expr;
508 if (tmp->type != E_EQUAL && tmp->type != E_UNEQUAL && tmp->type != E_SYMBOL)
509 return NULL;
510 sym1 = tmp->left.sym;
511 } else
512 sym1 = e1->left.sym;
513 if (e2->type == E_NOT) {
514 if (e2->left.expr->type != E_SYMBOL)
515 return NULL;
516 sym2 = e2->left.expr->left.sym;
517 } else
518 sym2 = e2->left.sym;
519 if (sym1 != sym2)
520 return NULL;
521 if (sym1->type != S_BOOLEAN && sym1->type != S_TRISTATE)
522 return NULL;
523
524 if ((e1->type == E_SYMBOL && e2->type == E_EQUAL && e2->right.sym == &symbol_yes) ||
525 (e2->type == E_SYMBOL && e1->type == E_EQUAL && e1->right.sym == &symbol_yes))
526 // (a) && (a='y') -> (a='y')
527 return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes);
528
529 if ((e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_no) ||
530 (e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_no))
531 // (a) && (a!='n') -> (a)
532 return expr_alloc_symbol(sym1);
533
534 if ((e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_mod) ||
535 (e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_mod))
536 // (a) && (a!='m') -> (a='y')
537 return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes);
538
539 if (sym1->type == S_TRISTATE) {
540 if (e1->type == E_EQUAL && e2->type == E_UNEQUAL) {
541 // (a='b') && (a!='c') -> 'b'='c' ? 'n' : a='b'
542 sym2 = e1->right.sym;
543 if ((e2->right.sym->flags & SYMBOL_CONST) && (sym2->flags & SYMBOL_CONST))
544 return sym2 != e2->right.sym ? expr_alloc_comp(E_EQUAL, sym1, sym2)
545 : expr_alloc_symbol(&symbol_no);
546 }
547 if (e1->type == E_UNEQUAL && e2->type == E_EQUAL) {
548 // (a='b') && (a!='c') -> 'b'='c' ? 'n' : a='b'
549 sym2 = e2->right.sym;
550 if ((e1->right.sym->flags & SYMBOL_CONST) && (sym2->flags & SYMBOL_CONST))
551 return sym2 != e1->right.sym ? expr_alloc_comp(E_EQUAL, sym1, sym2)
552 : expr_alloc_symbol(&symbol_no);
553 }
554 if (e1->type == E_UNEQUAL && e2->type == E_UNEQUAL &&
555 ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_no) ||
556 (e1->right.sym == &symbol_no && e2->right.sym == &symbol_yes)))
557 // (a!='y') && (a!='n') -> (a='m')
558 return expr_alloc_comp(E_EQUAL, sym1, &symbol_mod);
559
560 if (e1->type == E_UNEQUAL && e2->type == E_UNEQUAL &&
561 ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_mod) ||
562 (e1->right.sym == &symbol_mod && e2->right.sym == &symbol_yes)))
563 // (a!='y') && (a!='m') -> (a='n')
564 return expr_alloc_comp(E_EQUAL, sym1, &symbol_no);
565
566 if (e1->type == E_UNEQUAL && e2->type == E_UNEQUAL &&
567 ((e1->right.sym == &symbol_mod && e2->right.sym == &symbol_no) ||
568 (e1->right.sym == &symbol_no && e2->right.sym == &symbol_mod)))
569 // (a!='m') && (a!='n') -> (a='m')
570 return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes);
571
572 if ((e1->type == E_SYMBOL && e2->type == E_EQUAL && e2->right.sym == &symbol_mod) ||
573 (e2->type == E_SYMBOL && e1->type == E_EQUAL && e1->right.sym == &symbol_mod) ||
574 (e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_yes) ||
575 (e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_yes))
576 return NULL;
577 }
578
579 if (DEBUG_EXPR) {
580 printf("optimize (");
581 expr_fprint(e1, stdout);
582 printf(") && (");
583 expr_fprint(e2, stdout);
584 printf(")?\n");
585 }
586 return NULL;
587}
588
589/*
590 * expr_eliminate_dups() helper.
591 *
592 * Walks the two expression trees given in 'ep1' and 'ep2'. Any node that does
593 * not have type 'type' (E_OR/E_AND) is considered a leaf, and is compared
594 * against all other leaves to look for simplifications.
595 */
596static void expr_eliminate_dups1(enum expr_type type, struct expr **ep1, struct expr **ep2)
597{
598#define e1 (*ep1)
599#define e2 (*ep2)
600 struct expr *tmp;
601
602 /* Recurse down to leaves */
603
604 if (e1->type == type) {
605 expr_eliminate_dups1(type, &e1->left.expr, &e2);
606 expr_eliminate_dups1(type, &e1->right.expr, &e2);
607 return;
608 }
609 if (e2->type == type) {
610 expr_eliminate_dups1(type, &e1, &e2->left.expr);
611 expr_eliminate_dups1(type, &e1, &e2->right.expr);
612 return;
613 }
614
615 /* e1 and e2 are leaves. Compare and process them. */
616
617 if (e1 == e2)
618 return;
619
620 switch (e1->type) {
621 case E_OR: case E_AND:
622 expr_eliminate_dups1(e1->type, &e1, &e1);
623 default:
624 ;
625 }
626
627 switch (type) {
628 case E_OR:
629 tmp = expr_join_or(e1, e2);
630 if (tmp) {
631 expr_free(e1); expr_free(e2);
632 e1 = expr_alloc_symbol(&symbol_no);
633 e2 = tmp;
634 trans_count++;
635 }
636 break;
637 case E_AND:
638 tmp = expr_join_and(e1, e2);
639 if (tmp) {
640 expr_free(e1); expr_free(e2);
641 e1 = expr_alloc_symbol(&symbol_yes);
642 e2 = tmp;
643 trans_count++;
644 }
645 break;
646 default:
647 ;
648 }
649#undef e1
650#undef e2
651}
652
653/*
654 * Rewrites 'e' in-place to remove ("join") duplicate and other redundant
655 * operands.
656 *
657 * Example simplifications:
658 *
659 * A || B || A -> A || B
660 * A && B && A=y -> A=y && B
661 *
662 * Returns the deduplicated expression.
663 */
664struct expr *expr_eliminate_dups(struct expr *e)
665{
666 int oldcount;
667 if (!e)
668 return e;
669
670 oldcount = trans_count;
671 while (1) {
672 trans_count = 0;
673 switch (e->type) {
674 case E_OR: case E_AND:
675 expr_eliminate_dups1(e->type, &e, &e);
676 default:
677 ;
678 }
679 if (!trans_count)
680 /* No simplifications done in this pass. We're done */
681 break;
682 e = expr_eliminate_yn(e);
683 }
684 trans_count = oldcount;
685 return e;
686}
687
688/*
689 * Performs various simplifications involving logical operators and
690 * comparisons.
691 *
692 * Allocates and returns a new expression.
693 */
694struct expr *expr_transform(struct expr *e)
695{
696 struct expr *tmp;
697
698 if (!e)
699 return NULL;
700 switch (e->type) {
701 case E_EQUAL:
702 case E_GEQ:
703 case E_GTH:
704 case E_LEQ:
705 case E_LTH:
706 case E_UNEQUAL:
707 case E_SYMBOL:
708 case E_LIST:
709 break;
710 default:
711 e->left.expr = expr_transform(e->left.expr);
712 e->right.expr = expr_transform(e->right.expr);
713 }
714
715 switch (e->type) {
716 case E_EQUAL:
717 if (e->left.sym->type != S_BOOLEAN)
718 break;
719 if (e->right.sym == &symbol_no) {
720 e->type = E_NOT;
721 e->left.expr = expr_alloc_symbol(e->left.sym);
722 e->right.sym = NULL;
723 break;
724 }
725 if (e->right.sym == &symbol_mod) {
726 printf("boolean symbol %s tested for 'm'? test forced to 'n'\n", e->left.sym->name);
727 e->type = E_SYMBOL;
728 e->left.sym = &symbol_no;
729 e->right.sym = NULL;
730 break;
731 }
732 if (e->right.sym == &symbol_yes) {
733 e->type = E_SYMBOL;
734 e->right.sym = NULL;
735 break;
736 }
737 break;
738 case E_UNEQUAL:
739 if (e->left.sym->type != S_BOOLEAN)
740 break;
741 if (e->right.sym == &symbol_no) {
742 e->type = E_SYMBOL;
743 e->right.sym = NULL;
744 break;
745 }
746 if (e->right.sym == &symbol_mod) {
747 printf("boolean symbol %s tested for 'm'? test forced to 'y'\n", e->left.sym->name);
748 e->type = E_SYMBOL;
749 e->left.sym = &symbol_yes;
750 e->right.sym = NULL;
751 break;
752 }
753 if (e->right.sym == &symbol_yes) {
754 e->type = E_NOT;
755 e->left.expr = expr_alloc_symbol(e->left.sym);
756 e->right.sym = NULL;
757 break;
758 }
759 break;
760 case E_NOT:
761 switch (e->left.expr->type) {
762 case E_NOT:
763 // !!a -> a
764 tmp = e->left.expr->left.expr;
765 free(e->left.expr);
766 free(e);
767 e = tmp;
768 e = expr_transform(e);
769 break;
770 case E_EQUAL:
771 case E_UNEQUAL:
772 // !a='x' -> a!='x'
773 tmp = e->left.expr;
774 free(e);
775 e = tmp;
776 e->type = e->type == E_EQUAL ? E_UNEQUAL : E_EQUAL;
777 break;
778 case E_LEQ:
779 case E_GEQ:
780 // !a<='x' -> a>'x'
781 tmp = e->left.expr;
782 free(e);
783 e = tmp;
784 e->type = e->type == E_LEQ ? E_GTH : E_LTH;
785 break;
786 case E_LTH:
787 case E_GTH:
788 // !a<'x' -> a>='x'
789 tmp = e->left.expr;
790 free(e);
791 e = tmp;
792 e->type = e->type == E_LTH ? E_GEQ : E_LEQ;
793 break;
794 case E_OR:
795 // !(a || b) -> !a && !b
796 tmp = e->left.expr;
797 e->type = E_AND;
798 e->right.expr = expr_alloc_one(E_NOT, tmp->right.expr);
799 tmp->type = E_NOT;
800 tmp->right.expr = NULL;
801 e = expr_transform(e);
802 break;
803 case E_AND:
804 // !(a && b) -> !a || !b
805 tmp = e->left.expr;
806 e->type = E_OR;
807 e->right.expr = expr_alloc_one(E_NOT, tmp->right.expr);
808 tmp->type = E_NOT;
809 tmp->right.expr = NULL;
810 e = expr_transform(e);
811 break;
812 case E_SYMBOL:
813 if (e->left.expr->left.sym == &symbol_yes) {
814 // !'y' -> 'n'
815 tmp = e->left.expr;
816 free(e);
817 e = tmp;
818 e->type = E_SYMBOL;
819 e->left.sym = &symbol_no;
820 break;
821 }
822 if (e->left.expr->left.sym == &symbol_mod) {
823 // !'m' -> 'm'
824 tmp = e->left.expr;
825 free(e);
826 e = tmp;
827 e->type = E_SYMBOL;
828 e->left.sym = &symbol_mod;
829 break;
830 }
831 if (e->left.expr->left.sym == &symbol_no) {
832 // !'n' -> 'y'
833 tmp = e->left.expr;
834 free(e);
835 e = tmp;
836 e->type = E_SYMBOL;
837 e->left.sym = &symbol_yes;
838 break;
839 }
840 break;
841 default:
842 ;
843 }
844 break;
845 default:
846 ;
847 }
848 return e;
849}
850
851int expr_contains_symbol(struct expr *dep, struct symbol *sym)
852{
853 if (!dep)
854 return 0;
855
856 switch (dep->type) {
857 case E_AND:
858 case E_OR:
859 return expr_contains_symbol(dep->left.expr, sym) ||
860 expr_contains_symbol(dep->right.expr, sym);
861 case E_SYMBOL:
862 return dep->left.sym == sym;
863 case E_EQUAL:
864 case E_GEQ:
865 case E_GTH:
866 case E_LEQ:
867 case E_LTH:
868 case E_UNEQUAL:
869 return dep->left.sym == sym ||
870 dep->right.sym == sym;
871 case E_NOT:
872 return expr_contains_symbol(dep->left.expr, sym);
873 default:
874 ;
875 }
876 return 0;
877}
878
879bool expr_depends_symbol(struct expr *dep, struct symbol *sym)
880{
881 if (!dep)
882 return false;
883
884 switch (dep->type) {
885 case E_AND:
886 return expr_depends_symbol(dep->left.expr, sym) ||
887 expr_depends_symbol(dep->right.expr, sym);
888 case E_SYMBOL:
889 return dep->left.sym == sym;
890 case E_EQUAL:
891 if (dep->left.sym == sym) {
892 if (dep->right.sym == &symbol_yes || dep->right.sym == &symbol_mod)
893 return true;
894 }
895 break;
896 case E_UNEQUAL:
897 if (dep->left.sym == sym) {
898 if (dep->right.sym == &symbol_no)
899 return true;
900 }
901 break;
902 default:
903 ;
904 }
905 return false;
906}
907
908/*
909 * Inserts explicit comparisons of type 'type' to symbol 'sym' into the
910 * expression 'e'.
911 *
912 * Examples transformations for type == E_UNEQUAL, sym == &symbol_no:
913 *
914 * A -> A!=n
915 * !A -> A=n
916 * A && B -> !(A=n || B=n)
917 * A || B -> !(A=n && B=n)
918 * A && (B || C) -> !(A=n || (B=n && C=n))
919 *
920 * Allocates and returns a new expression.
921 */
922struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym)
923{
924 struct expr *e1, *e2;
925
926 if (!e) {
927 e = expr_alloc_symbol(sym);
928 if (type == E_UNEQUAL)
929 e = expr_alloc_one(E_NOT, e);
930 return e;
931 }
932 switch (e->type) {
933 case E_AND:
934 e1 = expr_trans_compare(e->left.expr, E_EQUAL, sym);
935 e2 = expr_trans_compare(e->right.expr, E_EQUAL, sym);
936 if (sym == &symbol_yes)
937 e = expr_alloc_two(E_AND, e1, e2);
938 if (sym == &symbol_no)
939 e = expr_alloc_two(E_OR, e1, e2);
940 if (type == E_UNEQUAL)
941 e = expr_alloc_one(E_NOT, e);
942 return e;
943 case E_OR:
944 e1 = expr_trans_compare(e->left.expr, E_EQUAL, sym);
945 e2 = expr_trans_compare(e->right.expr, E_EQUAL, sym);
946 if (sym == &symbol_yes)
947 e = expr_alloc_two(E_OR, e1, e2);
948 if (sym == &symbol_no)
949 e = expr_alloc_two(E_AND, e1, e2);
950 if (type == E_UNEQUAL)
951 e = expr_alloc_one(E_NOT, e);
952 return e;
953 case E_NOT:
954 return expr_trans_compare(e->left.expr, type == E_EQUAL ? E_UNEQUAL : E_EQUAL, sym);
955 case E_UNEQUAL:
956 case E_LTH:
957 case E_LEQ:
958 case E_GTH:
959 case E_GEQ:
960 case E_EQUAL:
961 if (type == E_EQUAL) {
962 if (sym == &symbol_yes)
963 return expr_copy(e);
964 if (sym == &symbol_mod)
965 return expr_alloc_symbol(&symbol_no);
966 if (sym == &symbol_no)
967 return expr_alloc_one(E_NOT, expr_copy(e));
968 } else {
969 if (sym == &symbol_yes)
970 return expr_alloc_one(E_NOT, expr_copy(e));
971 if (sym == &symbol_mod)
972 return expr_alloc_symbol(&symbol_yes);
973 if (sym == &symbol_no)
974 return expr_copy(e);
975 }
976 break;
977 case E_SYMBOL:
978 return expr_alloc_comp(type, e->left.sym, sym);
979 case E_LIST:
980 case E_RANGE:
981 case E_NONE:
982 /* panic */;
983 }
984 return NULL;
985}
986
987enum string_value_kind {
988 k_string,
989 k_signed,
990 k_unsigned,
991};
992
993union string_value {
994 unsigned long long u;
995 signed long long s;
996};
997
998static enum string_value_kind expr_parse_string(const char *str,
999 enum symbol_type type,
1000 union string_value *val)
1001{
1002 char *tail;
1003 enum string_value_kind kind;
1004
1005 errno = 0;
1006 switch (type) {
1007 case S_BOOLEAN:
1008 case S_TRISTATE:
1009 val->s = !strcmp(str, "n") ? 0 :
1010 !strcmp(str, "m") ? 1 :
1011 !strcmp(str, "y") ? 2 : -1;
1012 return k_signed;
1013 case S_INT:
1014 val->s = strtoll(str, &tail, 10);
1015 kind = k_signed;
1016 break;
1017 case S_HEX:
1018 val->u = strtoull(str, &tail, 16);
1019 kind = k_unsigned;
1020 break;
1021 default:
1022 val->s = strtoll(str, &tail, 0);
1023 kind = k_signed;
1024 break;
1025 }
1026 return !errno && !*tail && tail > str && isxdigit(tail[-1])
1027 ? kind : k_string;
1028}
1029
1030tristate expr_calc_value(struct expr *e)
1031{
1032 tristate val1, val2;
1033 const char *str1, *str2;
1034 enum string_value_kind k1 = k_string, k2 = k_string;
1035 union string_value lval = {}, rval = {};
1036 int res;
1037
1038 if (!e)
1039 return yes;
1040
1041 switch (e->type) {
1042 case E_SYMBOL:
1043 sym_calc_value(e->left.sym);
1044 return e->left.sym->curr.tri;
1045 case E_AND:
1046 val1 = expr_calc_value(e->left.expr);
1047 val2 = expr_calc_value(e->right.expr);
1048 return EXPR_AND(val1, val2);
1049 case E_OR:
1050 val1 = expr_calc_value(e->left.expr);
1051 val2 = expr_calc_value(e->right.expr);
1052 return EXPR_OR(val1, val2);
1053 case E_NOT:
1054 val1 = expr_calc_value(e->left.expr);
1055 return EXPR_NOT(val1);
1056 case E_EQUAL:
1057 case E_GEQ:
1058 case E_GTH:
1059 case E_LEQ:
1060 case E_LTH:
1061 case E_UNEQUAL:
1062 break;
1063 default:
1064 printf("expr_calc_value: %d?\n", e->type);
1065 return no;
1066 }
1067
1068 sym_calc_value(e->left.sym);
1069 sym_calc_value(e->right.sym);
1070 str1 = sym_get_string_value(e->left.sym);
1071 str2 = sym_get_string_value(e->right.sym);
1072
1073 if (e->left.sym->type != S_STRING || e->right.sym->type != S_STRING) {
1074 k1 = expr_parse_string(str1, e->left.sym->type, &lval);
1075 k2 = expr_parse_string(str2, e->right.sym->type, &rval);
1076 }
1077
1078 if (k1 == k_string || k2 == k_string)
1079 res = strcmp(str1, str2);
1080 else if (k1 == k_unsigned || k2 == k_unsigned)
1081 res = (lval.u > rval.u) - (lval.u < rval.u);
1082 else /* if (k1 == k_signed && k2 == k_signed) */
1083 res = (lval.s > rval.s) - (lval.s < rval.s);
1084
1085 switch(e->type) {
1086 case E_EQUAL:
1087 return res ? no : yes;
1088 case E_GEQ:
1089 return res >= 0 ? yes : no;
1090 case E_GTH:
1091 return res > 0 ? yes : no;
1092 case E_LEQ:
1093 return res <= 0 ? yes : no;
1094 case E_LTH:
1095 return res < 0 ? yes : no;
1096 case E_UNEQUAL:
1097 return res ? yes : no;
1098 default:
1099 printf("expr_calc_value: relation %d?\n", e->type);
1100 return no;
1101 }
1102}
1103
1104static int expr_compare_type(enum expr_type t1, enum expr_type t2)
1105{
1106 if (t1 == t2)
1107 return 0;
1108 switch (t1) {
1109 case E_LEQ:
1110 case E_LTH:
1111 case E_GEQ:
1112 case E_GTH:
1113 if (t2 == E_EQUAL || t2 == E_UNEQUAL)
1114 return 1;
1115 case E_EQUAL:
1116 case E_UNEQUAL:
1117 if (t2 == E_NOT)
1118 return 1;
1119 case E_NOT:
1120 if (t2 == E_AND)
1121 return 1;
1122 case E_AND:
1123 if (t2 == E_OR)
1124 return 1;
1125 case E_OR:
1126 if (t2 == E_LIST)
1127 return 1;
1128 case E_LIST:
1129 if (t2 == 0)
1130 return 1;
1131 default:
1132 return -1;
1133 }
1134 return 0;
1135}
1136
1137void expr_print(struct expr *e,
1138 void (*fn)(void *, struct symbol *, const char *),
1139 void *data, int prevtoken)
1140{
1141 if (!e) {
1142 fn(data, NULL, "y");
1143 return;
1144 }
1145
1146 if (expr_compare_type(prevtoken, e->type) > 0)
1147 fn(data, NULL, "(");
1148 switch (e->type) {
1149 case E_SYMBOL:
1150 if (e->left.sym->name)
1151 fn(data, e->left.sym, e->left.sym->name);
1152 else
1153 fn(data, NULL, "<choice>");
1154 break;
1155 case E_NOT:
1156 fn(data, NULL, "!");
1157 expr_print(e->left.expr, fn, data, E_NOT);
1158 break;
1159 case E_EQUAL:
1160 if (e->left.sym->name)
1161 fn(data, e->left.sym, e->left.sym->name);
1162 else
1163 fn(data, NULL, "<choice>");
1164 fn(data, NULL, "=");
1165 fn(data, e->right.sym, e->right.sym->name);
1166 break;
1167 case E_LEQ:
1168 case E_LTH:
1169 if (e->left.sym->name)
1170 fn(data, e->left.sym, e->left.sym->name);
1171 else
1172 fn(data, NULL, "<choice>");
1173 fn(data, NULL, e->type == E_LEQ ? "<=" : "<");
1174 fn(data, e->right.sym, e->right.sym->name);
1175 break;
1176 case E_GEQ:
1177 case E_GTH:
1178 if (e->left.sym->name)
1179 fn(data, e->left.sym, e->left.sym->name);
1180 else
1181 fn(data, NULL, "<choice>");
1182 fn(data, NULL, e->type == E_GEQ ? ">=" : ">");
1183 fn(data, e->right.sym, e->right.sym->name);
1184 break;
1185 case E_UNEQUAL:
1186 if (e->left.sym->name)
1187 fn(data, e->left.sym, e->left.sym->name);
1188 else
1189 fn(data, NULL, "<choice>");
1190 fn(data, NULL, "!=");
1191 fn(data, e->right.sym, e->right.sym->name);
1192 break;
1193 case E_OR:
1194 expr_print(e->left.expr, fn, data, E_OR);
1195 fn(data, NULL, " || ");
1196 expr_print(e->right.expr, fn, data, E_OR);
1197 break;
1198 case E_AND:
1199 expr_print(e->left.expr, fn, data, E_AND);
1200 fn(data, NULL, " && ");
1201 expr_print(e->right.expr, fn, data, E_AND);
1202 break;
1203 case E_LIST:
1204 fn(data, e->right.sym, e->right.sym->name);
1205 if (e->left.expr) {
1206 fn(data, NULL, " ^ ");
1207 expr_print(e->left.expr, fn, data, E_LIST);
1208 }
1209 break;
1210 case E_RANGE:
1211 fn(data, NULL, "[");
1212 fn(data, e->left.sym, e->left.sym->name);
1213 fn(data, NULL, " ");
1214 fn(data, e->right.sym, e->right.sym->name);
1215 fn(data, NULL, "]");
1216 break;
1217 default:
1218 {
1219 char buf[32];
1220 sprintf(buf, "<unknown type %d>", e->type);
1221 fn(data, NULL, buf);
1222 break;
1223 }
1224 }
1225 if (expr_compare_type(prevtoken, e->type) > 0)
1226 fn(data, NULL, ")");
1227}
1228
1229static void expr_print_file_helper(void *data, struct symbol *sym, const char *str)
1230{
1231 xfwrite(str, strlen(str), 1, data);
1232}
1233
1234void expr_fprint(struct expr *e, FILE *out)
1235{
1236 expr_print(e, expr_print_file_helper, out, E_NONE);
1237}
1238
1239static void expr_print_gstr_helper(void *data, struct symbol *sym, const char *str)
1240{
1241 struct gstr *gs = (struct gstr*)data;
1242 const char *sym_str = NULL;
1243
1244 if (sym)
1245 sym_str = sym_get_string_value(sym);
1246
1247 if (gs->max_width) {
1248 unsigned extra_length = strlen(str);
1249 const char *last_cr = strrchr(gs->s, '\n');
1250 unsigned last_line_length;
1251
1252 if (sym_str)
1253 extra_length += 4 + strlen(sym_str);
1254
1255 if (!last_cr)
1256 last_cr = gs->s;
1257
1258 last_line_length = strlen(gs->s) - (last_cr - gs->s);
1259
1260 if ((last_line_length + extra_length) > gs->max_width)
1261 str_append(gs, "\\\n");
1262 }
1263
1264 str_append(gs, str);
1265 if (sym && sym->type != S_UNKNOWN)
1266 str_printf(gs, " [=%s]", sym_str);
1267}
1268
1269void expr_gstr_print(struct expr *e, struct gstr *gs)
1270{
1271 expr_print(e, expr_print_gstr_helper, gs, E_NONE);
1272}
1273
1274/*
1275 * Transform the top level "||" tokens into newlines and prepend each
1276 * line with a minus. This makes expressions much easier to read.
1277 * Suitable for reverse dependency expressions.
1278 */
1279static void expr_print_revdep(struct expr *e,
1280 void (*fn)(void *, struct symbol *, const char *),
1281 void *data, tristate pr_type, const char **title)
1282{
1283 if (e->type == E_OR) {
1284 expr_print_revdep(e->left.expr, fn, data, pr_type, title);
1285 expr_print_revdep(e->right.expr, fn, data, pr_type, title);
1286 } else if (expr_calc_value(e) == pr_type) {
1287 if (*title) {
1288 fn(data, NULL, *title);
1289 *title = NULL;
1290 }
1291
1292 fn(data, NULL, " - ");
1293 expr_print(e, fn, data, E_NONE);
1294 fn(data, NULL, "\n");
1295 }
1296}
1297
1298void expr_gstr_print_revdep(struct expr *e, struct gstr *gs,
1299 tristate pr_type, const char *title)
1300{
1301 expr_print_revdep(e, expr_print_gstr_helper, gs, pr_type, &title);
1302}
1/*
2 * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
3 * Released under the terms of the GNU GPL v2.0.
4 */
5
6#include <stdio.h>
7#include <stdlib.h>
8#include <string.h>
9
10#include "lkc.h"
11
12#define DEBUG_EXPR 0
13
14struct expr *expr_alloc_symbol(struct symbol *sym)
15{
16 struct expr *e = xcalloc(1, sizeof(*e));
17 e->type = E_SYMBOL;
18 e->left.sym = sym;
19 return e;
20}
21
22struct expr *expr_alloc_one(enum expr_type type, struct expr *ce)
23{
24 struct expr *e = xcalloc(1, sizeof(*e));
25 e->type = type;
26 e->left.expr = ce;
27 return e;
28}
29
30struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2)
31{
32 struct expr *e = xcalloc(1, sizeof(*e));
33 e->type = type;
34 e->left.expr = e1;
35 e->right.expr = e2;
36 return e;
37}
38
39struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2)
40{
41 struct expr *e = xcalloc(1, sizeof(*e));
42 e->type = type;
43 e->left.sym = s1;
44 e->right.sym = s2;
45 return e;
46}
47
48struct expr *expr_alloc_and(struct expr *e1, struct expr *e2)
49{
50 if (!e1)
51 return e2;
52 return e2 ? expr_alloc_two(E_AND, e1, e2) : e1;
53}
54
55struct expr *expr_alloc_or(struct expr *e1, struct expr *e2)
56{
57 if (!e1)
58 return e2;
59 return e2 ? expr_alloc_two(E_OR, e1, e2) : e1;
60}
61
62struct expr *expr_copy(const struct expr *org)
63{
64 struct expr *e;
65
66 if (!org)
67 return NULL;
68
69 e = xmalloc(sizeof(*org));
70 memcpy(e, org, sizeof(*org));
71 switch (org->type) {
72 case E_SYMBOL:
73 e->left = org->left;
74 break;
75 case E_NOT:
76 e->left.expr = expr_copy(org->left.expr);
77 break;
78 case E_EQUAL:
79 case E_UNEQUAL:
80 e->left.sym = org->left.sym;
81 e->right.sym = org->right.sym;
82 break;
83 case E_AND:
84 case E_OR:
85 case E_LIST:
86 e->left.expr = expr_copy(org->left.expr);
87 e->right.expr = expr_copy(org->right.expr);
88 break;
89 default:
90 printf("can't copy type %d\n", e->type);
91 free(e);
92 e = NULL;
93 break;
94 }
95
96 return e;
97}
98
99void expr_free(struct expr *e)
100{
101 if (!e)
102 return;
103
104 switch (e->type) {
105 case E_SYMBOL:
106 break;
107 case E_NOT:
108 expr_free(e->left.expr);
109 return;
110 case E_EQUAL:
111 case E_UNEQUAL:
112 break;
113 case E_OR:
114 case E_AND:
115 expr_free(e->left.expr);
116 expr_free(e->right.expr);
117 break;
118 default:
119 printf("how to free type %d?\n", e->type);
120 break;
121 }
122 free(e);
123}
124
125static int trans_count;
126
127#define e1 (*ep1)
128#define e2 (*ep2)
129
130static void __expr_eliminate_eq(enum expr_type type, struct expr **ep1, struct expr **ep2)
131{
132 if (e1->type == type) {
133 __expr_eliminate_eq(type, &e1->left.expr, &e2);
134 __expr_eliminate_eq(type, &e1->right.expr, &e2);
135 return;
136 }
137 if (e2->type == type) {
138 __expr_eliminate_eq(type, &e1, &e2->left.expr);
139 __expr_eliminate_eq(type, &e1, &e2->right.expr);
140 return;
141 }
142 if (e1->type == E_SYMBOL && e2->type == E_SYMBOL &&
143 e1->left.sym == e2->left.sym &&
144 (e1->left.sym == &symbol_yes || e1->left.sym == &symbol_no))
145 return;
146 if (!expr_eq(e1, e2))
147 return;
148 trans_count++;
149 expr_free(e1); expr_free(e2);
150 switch (type) {
151 case E_OR:
152 e1 = expr_alloc_symbol(&symbol_no);
153 e2 = expr_alloc_symbol(&symbol_no);
154 break;
155 case E_AND:
156 e1 = expr_alloc_symbol(&symbol_yes);
157 e2 = expr_alloc_symbol(&symbol_yes);
158 break;
159 default:
160 ;
161 }
162}
163
164void expr_eliminate_eq(struct expr **ep1, struct expr **ep2)
165{
166 if (!e1 || !e2)
167 return;
168 switch (e1->type) {
169 case E_OR:
170 case E_AND:
171 __expr_eliminate_eq(e1->type, ep1, ep2);
172 default:
173 ;
174 }
175 if (e1->type != e2->type) switch (e2->type) {
176 case E_OR:
177 case E_AND:
178 __expr_eliminate_eq(e2->type, ep1, ep2);
179 default:
180 ;
181 }
182 e1 = expr_eliminate_yn(e1);
183 e2 = expr_eliminate_yn(e2);
184}
185
186#undef e1
187#undef e2
188
189int expr_eq(struct expr *e1, struct expr *e2)
190{
191 int res, old_count;
192
193 if (e1->type != e2->type)
194 return 0;
195 switch (e1->type) {
196 case E_EQUAL:
197 case E_UNEQUAL:
198 return e1->left.sym == e2->left.sym && e1->right.sym == e2->right.sym;
199 case E_SYMBOL:
200 return e1->left.sym == e2->left.sym;
201 case E_NOT:
202 return expr_eq(e1->left.expr, e2->left.expr);
203 case E_AND:
204 case E_OR:
205 e1 = expr_copy(e1);
206 e2 = expr_copy(e2);
207 old_count = trans_count;
208 expr_eliminate_eq(&e1, &e2);
209 res = (e1->type == E_SYMBOL && e2->type == E_SYMBOL &&
210 e1->left.sym == e2->left.sym);
211 expr_free(e1);
212 expr_free(e2);
213 trans_count = old_count;
214 return res;
215 case E_LIST:
216 case E_RANGE:
217 case E_NONE:
218 /* panic */;
219 }
220
221 if (DEBUG_EXPR) {
222 expr_fprint(e1, stdout);
223 printf(" = ");
224 expr_fprint(e2, stdout);
225 printf(" ?\n");
226 }
227
228 return 0;
229}
230
231struct expr *expr_eliminate_yn(struct expr *e)
232{
233 struct expr *tmp;
234
235 if (e) switch (e->type) {
236 case E_AND:
237 e->left.expr = expr_eliminate_yn(e->left.expr);
238 e->right.expr = expr_eliminate_yn(e->right.expr);
239 if (e->left.expr->type == E_SYMBOL) {
240 if (e->left.expr->left.sym == &symbol_no) {
241 expr_free(e->left.expr);
242 expr_free(e->right.expr);
243 e->type = E_SYMBOL;
244 e->left.sym = &symbol_no;
245 e->right.expr = NULL;
246 return e;
247 } else if (e->left.expr->left.sym == &symbol_yes) {
248 free(e->left.expr);
249 tmp = e->right.expr;
250 *e = *(e->right.expr);
251 free(tmp);
252 return e;
253 }
254 }
255 if (e->right.expr->type == E_SYMBOL) {
256 if (e->right.expr->left.sym == &symbol_no) {
257 expr_free(e->left.expr);
258 expr_free(e->right.expr);
259 e->type = E_SYMBOL;
260 e->left.sym = &symbol_no;
261 e->right.expr = NULL;
262 return e;
263 } else if (e->right.expr->left.sym == &symbol_yes) {
264 free(e->right.expr);
265 tmp = e->left.expr;
266 *e = *(e->left.expr);
267 free(tmp);
268 return e;
269 }
270 }
271 break;
272 case E_OR:
273 e->left.expr = expr_eliminate_yn(e->left.expr);
274 e->right.expr = expr_eliminate_yn(e->right.expr);
275 if (e->left.expr->type == E_SYMBOL) {
276 if (e->left.expr->left.sym == &symbol_no) {
277 free(e->left.expr);
278 tmp = e->right.expr;
279 *e = *(e->right.expr);
280 free(tmp);
281 return e;
282 } else if (e->left.expr->left.sym == &symbol_yes) {
283 expr_free(e->left.expr);
284 expr_free(e->right.expr);
285 e->type = E_SYMBOL;
286 e->left.sym = &symbol_yes;
287 e->right.expr = NULL;
288 return e;
289 }
290 }
291 if (e->right.expr->type == E_SYMBOL) {
292 if (e->right.expr->left.sym == &symbol_no) {
293 free(e->right.expr);
294 tmp = e->left.expr;
295 *e = *(e->left.expr);
296 free(tmp);
297 return e;
298 } else if (e->right.expr->left.sym == &symbol_yes) {
299 expr_free(e->left.expr);
300 expr_free(e->right.expr);
301 e->type = E_SYMBOL;
302 e->left.sym = &symbol_yes;
303 e->right.expr = NULL;
304 return e;
305 }
306 }
307 break;
308 default:
309 ;
310 }
311 return e;
312}
313
314/*
315 * bool FOO!=n => FOO
316 */
317struct expr *expr_trans_bool(struct expr *e)
318{
319 if (!e)
320 return NULL;
321 switch (e->type) {
322 case E_AND:
323 case E_OR:
324 case E_NOT:
325 e->left.expr = expr_trans_bool(e->left.expr);
326 e->right.expr = expr_trans_bool(e->right.expr);
327 break;
328 case E_UNEQUAL:
329 // FOO!=n -> FOO
330 if (e->left.sym->type == S_TRISTATE) {
331 if (e->right.sym == &symbol_no) {
332 e->type = E_SYMBOL;
333 e->right.sym = NULL;
334 }
335 }
336 break;
337 default:
338 ;
339 }
340 return e;
341}
342
343/*
344 * e1 || e2 -> ?
345 */
346static struct expr *expr_join_or(struct expr *e1, struct expr *e2)
347{
348 struct expr *tmp;
349 struct symbol *sym1, *sym2;
350
351 if (expr_eq(e1, e2))
352 return expr_copy(e1);
353 if (e1->type != E_EQUAL && e1->type != E_UNEQUAL && e1->type != E_SYMBOL && e1->type != E_NOT)
354 return NULL;
355 if (e2->type != E_EQUAL && e2->type != E_UNEQUAL && e2->type != E_SYMBOL && e2->type != E_NOT)
356 return NULL;
357 if (e1->type == E_NOT) {
358 tmp = e1->left.expr;
359 if (tmp->type != E_EQUAL && tmp->type != E_UNEQUAL && tmp->type != E_SYMBOL)
360 return NULL;
361 sym1 = tmp->left.sym;
362 } else
363 sym1 = e1->left.sym;
364 if (e2->type == E_NOT) {
365 if (e2->left.expr->type != E_SYMBOL)
366 return NULL;
367 sym2 = e2->left.expr->left.sym;
368 } else
369 sym2 = e2->left.sym;
370 if (sym1 != sym2)
371 return NULL;
372 if (sym1->type != S_BOOLEAN && sym1->type != S_TRISTATE)
373 return NULL;
374 if (sym1->type == S_TRISTATE) {
375 if (e1->type == E_EQUAL && e2->type == E_EQUAL &&
376 ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_mod) ||
377 (e1->right.sym == &symbol_mod && e2->right.sym == &symbol_yes))) {
378 // (a='y') || (a='m') -> (a!='n')
379 return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_no);
380 }
381 if (e1->type == E_EQUAL && e2->type == E_EQUAL &&
382 ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_no) ||
383 (e1->right.sym == &symbol_no && e2->right.sym == &symbol_yes))) {
384 // (a='y') || (a='n') -> (a!='m')
385 return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_mod);
386 }
387 if (e1->type == E_EQUAL && e2->type == E_EQUAL &&
388 ((e1->right.sym == &symbol_mod && e2->right.sym == &symbol_no) ||
389 (e1->right.sym == &symbol_no && e2->right.sym == &symbol_mod))) {
390 // (a='m') || (a='n') -> (a!='y')
391 return expr_alloc_comp(E_UNEQUAL, sym1, &symbol_yes);
392 }
393 }
394 if (sym1->type == S_BOOLEAN && sym1 == sym2) {
395 if ((e1->type == E_NOT && e1->left.expr->type == E_SYMBOL && e2->type == E_SYMBOL) ||
396 (e2->type == E_NOT && e2->left.expr->type == E_SYMBOL && e1->type == E_SYMBOL))
397 return expr_alloc_symbol(&symbol_yes);
398 }
399
400 if (DEBUG_EXPR) {
401 printf("optimize (");
402 expr_fprint(e1, stdout);
403 printf(") || (");
404 expr_fprint(e2, stdout);
405 printf(")?\n");
406 }
407 return NULL;
408}
409
410static struct expr *expr_join_and(struct expr *e1, struct expr *e2)
411{
412 struct expr *tmp;
413 struct symbol *sym1, *sym2;
414
415 if (expr_eq(e1, e2))
416 return expr_copy(e1);
417 if (e1->type != E_EQUAL && e1->type != E_UNEQUAL && e1->type != E_SYMBOL && e1->type != E_NOT)
418 return NULL;
419 if (e2->type != E_EQUAL && e2->type != E_UNEQUAL && e2->type != E_SYMBOL && e2->type != E_NOT)
420 return NULL;
421 if (e1->type == E_NOT) {
422 tmp = e1->left.expr;
423 if (tmp->type != E_EQUAL && tmp->type != E_UNEQUAL && tmp->type != E_SYMBOL)
424 return NULL;
425 sym1 = tmp->left.sym;
426 } else
427 sym1 = e1->left.sym;
428 if (e2->type == E_NOT) {
429 if (e2->left.expr->type != E_SYMBOL)
430 return NULL;
431 sym2 = e2->left.expr->left.sym;
432 } else
433 sym2 = e2->left.sym;
434 if (sym1 != sym2)
435 return NULL;
436 if (sym1->type != S_BOOLEAN && sym1->type != S_TRISTATE)
437 return NULL;
438
439 if ((e1->type == E_SYMBOL && e2->type == E_EQUAL && e2->right.sym == &symbol_yes) ||
440 (e2->type == E_SYMBOL && e1->type == E_EQUAL && e1->right.sym == &symbol_yes))
441 // (a) && (a='y') -> (a='y')
442 return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes);
443
444 if ((e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_no) ||
445 (e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_no))
446 // (a) && (a!='n') -> (a)
447 return expr_alloc_symbol(sym1);
448
449 if ((e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_mod) ||
450 (e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_mod))
451 // (a) && (a!='m') -> (a='y')
452 return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes);
453
454 if (sym1->type == S_TRISTATE) {
455 if (e1->type == E_EQUAL && e2->type == E_UNEQUAL) {
456 // (a='b') && (a!='c') -> 'b'='c' ? 'n' : a='b'
457 sym2 = e1->right.sym;
458 if ((e2->right.sym->flags & SYMBOL_CONST) && (sym2->flags & SYMBOL_CONST))
459 return sym2 != e2->right.sym ? expr_alloc_comp(E_EQUAL, sym1, sym2)
460 : expr_alloc_symbol(&symbol_no);
461 }
462 if (e1->type == E_UNEQUAL && e2->type == E_EQUAL) {
463 // (a='b') && (a!='c') -> 'b'='c' ? 'n' : a='b'
464 sym2 = e2->right.sym;
465 if ((e1->right.sym->flags & SYMBOL_CONST) && (sym2->flags & SYMBOL_CONST))
466 return sym2 != e1->right.sym ? expr_alloc_comp(E_EQUAL, sym1, sym2)
467 : expr_alloc_symbol(&symbol_no);
468 }
469 if (e1->type == E_UNEQUAL && e2->type == E_UNEQUAL &&
470 ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_no) ||
471 (e1->right.sym == &symbol_no && e2->right.sym == &symbol_yes)))
472 // (a!='y') && (a!='n') -> (a='m')
473 return expr_alloc_comp(E_EQUAL, sym1, &symbol_mod);
474
475 if (e1->type == E_UNEQUAL && e2->type == E_UNEQUAL &&
476 ((e1->right.sym == &symbol_yes && e2->right.sym == &symbol_mod) ||
477 (e1->right.sym == &symbol_mod && e2->right.sym == &symbol_yes)))
478 // (a!='y') && (a!='m') -> (a='n')
479 return expr_alloc_comp(E_EQUAL, sym1, &symbol_no);
480
481 if (e1->type == E_UNEQUAL && e2->type == E_UNEQUAL &&
482 ((e1->right.sym == &symbol_mod && e2->right.sym == &symbol_no) ||
483 (e1->right.sym == &symbol_no && e2->right.sym == &symbol_mod)))
484 // (a!='m') && (a!='n') -> (a='m')
485 return expr_alloc_comp(E_EQUAL, sym1, &symbol_yes);
486
487 if ((e1->type == E_SYMBOL && e2->type == E_EQUAL && e2->right.sym == &symbol_mod) ||
488 (e2->type == E_SYMBOL && e1->type == E_EQUAL && e1->right.sym == &symbol_mod) ||
489 (e1->type == E_SYMBOL && e2->type == E_UNEQUAL && e2->right.sym == &symbol_yes) ||
490 (e2->type == E_SYMBOL && e1->type == E_UNEQUAL && e1->right.sym == &symbol_yes))
491 return NULL;
492 }
493
494 if (DEBUG_EXPR) {
495 printf("optimize (");
496 expr_fprint(e1, stdout);
497 printf(") && (");
498 expr_fprint(e2, stdout);
499 printf(")?\n");
500 }
501 return NULL;
502}
503
504static void expr_eliminate_dups1(enum expr_type type, struct expr **ep1, struct expr **ep2)
505{
506#define e1 (*ep1)
507#define e2 (*ep2)
508 struct expr *tmp;
509
510 if (e1->type == type) {
511 expr_eliminate_dups1(type, &e1->left.expr, &e2);
512 expr_eliminate_dups1(type, &e1->right.expr, &e2);
513 return;
514 }
515 if (e2->type == type) {
516 expr_eliminate_dups1(type, &e1, &e2->left.expr);
517 expr_eliminate_dups1(type, &e1, &e2->right.expr);
518 return;
519 }
520 if (e1 == e2)
521 return;
522
523 switch (e1->type) {
524 case E_OR: case E_AND:
525 expr_eliminate_dups1(e1->type, &e1, &e1);
526 default:
527 ;
528 }
529
530 switch (type) {
531 case E_OR:
532 tmp = expr_join_or(e1, e2);
533 if (tmp) {
534 expr_free(e1); expr_free(e2);
535 e1 = expr_alloc_symbol(&symbol_no);
536 e2 = tmp;
537 trans_count++;
538 }
539 break;
540 case E_AND:
541 tmp = expr_join_and(e1, e2);
542 if (tmp) {
543 expr_free(e1); expr_free(e2);
544 e1 = expr_alloc_symbol(&symbol_yes);
545 e2 = tmp;
546 trans_count++;
547 }
548 break;
549 default:
550 ;
551 }
552#undef e1
553#undef e2
554}
555
556static void expr_eliminate_dups2(enum expr_type type, struct expr **ep1, struct expr **ep2)
557{
558#define e1 (*ep1)
559#define e2 (*ep2)
560 struct expr *tmp, *tmp1, *tmp2;
561
562 if (e1->type == type) {
563 expr_eliminate_dups2(type, &e1->left.expr, &e2);
564 expr_eliminate_dups2(type, &e1->right.expr, &e2);
565 return;
566 }
567 if (e2->type == type) {
568 expr_eliminate_dups2(type, &e1, &e2->left.expr);
569 expr_eliminate_dups2(type, &e1, &e2->right.expr);
570 }
571 if (e1 == e2)
572 return;
573
574 switch (e1->type) {
575 case E_OR:
576 expr_eliminate_dups2(e1->type, &e1, &e1);
577 // (FOO || BAR) && (!FOO && !BAR) -> n
578 tmp1 = expr_transform(expr_alloc_one(E_NOT, expr_copy(e1)));
579 tmp2 = expr_copy(e2);
580 tmp = expr_extract_eq_and(&tmp1, &tmp2);
581 if (expr_is_yes(tmp1)) {
582 expr_free(e1);
583 e1 = expr_alloc_symbol(&symbol_no);
584 trans_count++;
585 }
586 expr_free(tmp2);
587 expr_free(tmp1);
588 expr_free(tmp);
589 break;
590 case E_AND:
591 expr_eliminate_dups2(e1->type, &e1, &e1);
592 // (FOO && BAR) || (!FOO || !BAR) -> y
593 tmp1 = expr_transform(expr_alloc_one(E_NOT, expr_copy(e1)));
594 tmp2 = expr_copy(e2);
595 tmp = expr_extract_eq_or(&tmp1, &tmp2);
596 if (expr_is_no(tmp1)) {
597 expr_free(e1);
598 e1 = expr_alloc_symbol(&symbol_yes);
599 trans_count++;
600 }
601 expr_free(tmp2);
602 expr_free(tmp1);
603 expr_free(tmp);
604 break;
605 default:
606 ;
607 }
608#undef e1
609#undef e2
610}
611
612struct expr *expr_eliminate_dups(struct expr *e)
613{
614 int oldcount;
615 if (!e)
616 return e;
617
618 oldcount = trans_count;
619 while (1) {
620 trans_count = 0;
621 switch (e->type) {
622 case E_OR: case E_AND:
623 expr_eliminate_dups1(e->type, &e, &e);
624 expr_eliminate_dups2(e->type, &e, &e);
625 default:
626 ;
627 }
628 if (!trans_count)
629 break;
630 e = expr_eliminate_yn(e);
631 }
632 trans_count = oldcount;
633 return e;
634}
635
636struct expr *expr_transform(struct expr *e)
637{
638 struct expr *tmp;
639
640 if (!e)
641 return NULL;
642 switch (e->type) {
643 case E_EQUAL:
644 case E_UNEQUAL:
645 case E_SYMBOL:
646 case E_LIST:
647 break;
648 default:
649 e->left.expr = expr_transform(e->left.expr);
650 e->right.expr = expr_transform(e->right.expr);
651 }
652
653 switch (e->type) {
654 case E_EQUAL:
655 if (e->left.sym->type != S_BOOLEAN)
656 break;
657 if (e->right.sym == &symbol_no) {
658 e->type = E_NOT;
659 e->left.expr = expr_alloc_symbol(e->left.sym);
660 e->right.sym = NULL;
661 break;
662 }
663 if (e->right.sym == &symbol_mod) {
664 printf("boolean symbol %s tested for 'm'? test forced to 'n'\n", e->left.sym->name);
665 e->type = E_SYMBOL;
666 e->left.sym = &symbol_no;
667 e->right.sym = NULL;
668 break;
669 }
670 if (e->right.sym == &symbol_yes) {
671 e->type = E_SYMBOL;
672 e->right.sym = NULL;
673 break;
674 }
675 break;
676 case E_UNEQUAL:
677 if (e->left.sym->type != S_BOOLEAN)
678 break;
679 if (e->right.sym == &symbol_no) {
680 e->type = E_SYMBOL;
681 e->right.sym = NULL;
682 break;
683 }
684 if (e->right.sym == &symbol_mod) {
685 printf("boolean symbol %s tested for 'm'? test forced to 'y'\n", e->left.sym->name);
686 e->type = E_SYMBOL;
687 e->left.sym = &symbol_yes;
688 e->right.sym = NULL;
689 break;
690 }
691 if (e->right.sym == &symbol_yes) {
692 e->type = E_NOT;
693 e->left.expr = expr_alloc_symbol(e->left.sym);
694 e->right.sym = NULL;
695 break;
696 }
697 break;
698 case E_NOT:
699 switch (e->left.expr->type) {
700 case E_NOT:
701 // !!a -> a
702 tmp = e->left.expr->left.expr;
703 free(e->left.expr);
704 free(e);
705 e = tmp;
706 e = expr_transform(e);
707 break;
708 case E_EQUAL:
709 case E_UNEQUAL:
710 // !a='x' -> a!='x'
711 tmp = e->left.expr;
712 free(e);
713 e = tmp;
714 e->type = e->type == E_EQUAL ? E_UNEQUAL : E_EQUAL;
715 break;
716 case E_OR:
717 // !(a || b) -> !a && !b
718 tmp = e->left.expr;
719 e->type = E_AND;
720 e->right.expr = expr_alloc_one(E_NOT, tmp->right.expr);
721 tmp->type = E_NOT;
722 tmp->right.expr = NULL;
723 e = expr_transform(e);
724 break;
725 case E_AND:
726 // !(a && b) -> !a || !b
727 tmp = e->left.expr;
728 e->type = E_OR;
729 e->right.expr = expr_alloc_one(E_NOT, tmp->right.expr);
730 tmp->type = E_NOT;
731 tmp->right.expr = NULL;
732 e = expr_transform(e);
733 break;
734 case E_SYMBOL:
735 if (e->left.expr->left.sym == &symbol_yes) {
736 // !'y' -> 'n'
737 tmp = e->left.expr;
738 free(e);
739 e = tmp;
740 e->type = E_SYMBOL;
741 e->left.sym = &symbol_no;
742 break;
743 }
744 if (e->left.expr->left.sym == &symbol_mod) {
745 // !'m' -> 'm'
746 tmp = e->left.expr;
747 free(e);
748 e = tmp;
749 e->type = E_SYMBOL;
750 e->left.sym = &symbol_mod;
751 break;
752 }
753 if (e->left.expr->left.sym == &symbol_no) {
754 // !'n' -> 'y'
755 tmp = e->left.expr;
756 free(e);
757 e = tmp;
758 e->type = E_SYMBOL;
759 e->left.sym = &symbol_yes;
760 break;
761 }
762 break;
763 default:
764 ;
765 }
766 break;
767 default:
768 ;
769 }
770 return e;
771}
772
773int expr_contains_symbol(struct expr *dep, struct symbol *sym)
774{
775 if (!dep)
776 return 0;
777
778 switch (dep->type) {
779 case E_AND:
780 case E_OR:
781 return expr_contains_symbol(dep->left.expr, sym) ||
782 expr_contains_symbol(dep->right.expr, sym);
783 case E_SYMBOL:
784 return dep->left.sym == sym;
785 case E_EQUAL:
786 case E_UNEQUAL:
787 return dep->left.sym == sym ||
788 dep->right.sym == sym;
789 case E_NOT:
790 return expr_contains_symbol(dep->left.expr, sym);
791 default:
792 ;
793 }
794 return 0;
795}
796
797bool expr_depends_symbol(struct expr *dep, struct symbol *sym)
798{
799 if (!dep)
800 return false;
801
802 switch (dep->type) {
803 case E_AND:
804 return expr_depends_symbol(dep->left.expr, sym) ||
805 expr_depends_symbol(dep->right.expr, sym);
806 case E_SYMBOL:
807 return dep->left.sym == sym;
808 case E_EQUAL:
809 if (dep->left.sym == sym) {
810 if (dep->right.sym == &symbol_yes || dep->right.sym == &symbol_mod)
811 return true;
812 }
813 break;
814 case E_UNEQUAL:
815 if (dep->left.sym == sym) {
816 if (dep->right.sym == &symbol_no)
817 return true;
818 }
819 break;
820 default:
821 ;
822 }
823 return false;
824}
825
826struct expr *expr_extract_eq_and(struct expr **ep1, struct expr **ep2)
827{
828 struct expr *tmp = NULL;
829 expr_extract_eq(E_AND, &tmp, ep1, ep2);
830 if (tmp) {
831 *ep1 = expr_eliminate_yn(*ep1);
832 *ep2 = expr_eliminate_yn(*ep2);
833 }
834 return tmp;
835}
836
837struct expr *expr_extract_eq_or(struct expr **ep1, struct expr **ep2)
838{
839 struct expr *tmp = NULL;
840 expr_extract_eq(E_OR, &tmp, ep1, ep2);
841 if (tmp) {
842 *ep1 = expr_eliminate_yn(*ep1);
843 *ep2 = expr_eliminate_yn(*ep2);
844 }
845 return tmp;
846}
847
848void expr_extract_eq(enum expr_type type, struct expr **ep, struct expr **ep1, struct expr **ep2)
849{
850#define e1 (*ep1)
851#define e2 (*ep2)
852 if (e1->type == type) {
853 expr_extract_eq(type, ep, &e1->left.expr, &e2);
854 expr_extract_eq(type, ep, &e1->right.expr, &e2);
855 return;
856 }
857 if (e2->type == type) {
858 expr_extract_eq(type, ep, ep1, &e2->left.expr);
859 expr_extract_eq(type, ep, ep1, &e2->right.expr);
860 return;
861 }
862 if (expr_eq(e1, e2)) {
863 *ep = *ep ? expr_alloc_two(type, *ep, e1) : e1;
864 expr_free(e2);
865 if (type == E_AND) {
866 e1 = expr_alloc_symbol(&symbol_yes);
867 e2 = expr_alloc_symbol(&symbol_yes);
868 } else if (type == E_OR) {
869 e1 = expr_alloc_symbol(&symbol_no);
870 e2 = expr_alloc_symbol(&symbol_no);
871 }
872 }
873#undef e1
874#undef e2
875}
876
877struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym)
878{
879 struct expr *e1, *e2;
880
881 if (!e) {
882 e = expr_alloc_symbol(sym);
883 if (type == E_UNEQUAL)
884 e = expr_alloc_one(E_NOT, e);
885 return e;
886 }
887 switch (e->type) {
888 case E_AND:
889 e1 = expr_trans_compare(e->left.expr, E_EQUAL, sym);
890 e2 = expr_trans_compare(e->right.expr, E_EQUAL, sym);
891 if (sym == &symbol_yes)
892 e = expr_alloc_two(E_AND, e1, e2);
893 if (sym == &symbol_no)
894 e = expr_alloc_two(E_OR, e1, e2);
895 if (type == E_UNEQUAL)
896 e = expr_alloc_one(E_NOT, e);
897 return e;
898 case E_OR:
899 e1 = expr_trans_compare(e->left.expr, E_EQUAL, sym);
900 e2 = expr_trans_compare(e->right.expr, E_EQUAL, sym);
901 if (sym == &symbol_yes)
902 e = expr_alloc_two(E_OR, e1, e2);
903 if (sym == &symbol_no)
904 e = expr_alloc_two(E_AND, e1, e2);
905 if (type == E_UNEQUAL)
906 e = expr_alloc_one(E_NOT, e);
907 return e;
908 case E_NOT:
909 return expr_trans_compare(e->left.expr, type == E_EQUAL ? E_UNEQUAL : E_EQUAL, sym);
910 case E_UNEQUAL:
911 case E_EQUAL:
912 if (type == E_EQUAL) {
913 if (sym == &symbol_yes)
914 return expr_copy(e);
915 if (sym == &symbol_mod)
916 return expr_alloc_symbol(&symbol_no);
917 if (sym == &symbol_no)
918 return expr_alloc_one(E_NOT, expr_copy(e));
919 } else {
920 if (sym == &symbol_yes)
921 return expr_alloc_one(E_NOT, expr_copy(e));
922 if (sym == &symbol_mod)
923 return expr_alloc_symbol(&symbol_yes);
924 if (sym == &symbol_no)
925 return expr_copy(e);
926 }
927 break;
928 case E_SYMBOL:
929 return expr_alloc_comp(type, e->left.sym, sym);
930 case E_LIST:
931 case E_RANGE:
932 case E_NONE:
933 /* panic */;
934 }
935 return NULL;
936}
937
938tristate expr_calc_value(struct expr *e)
939{
940 tristate val1, val2;
941 const char *str1, *str2;
942
943 if (!e)
944 return yes;
945
946 switch (e->type) {
947 case E_SYMBOL:
948 sym_calc_value(e->left.sym);
949 return e->left.sym->curr.tri;
950 case E_AND:
951 val1 = expr_calc_value(e->left.expr);
952 val2 = expr_calc_value(e->right.expr);
953 return EXPR_AND(val1, val2);
954 case E_OR:
955 val1 = expr_calc_value(e->left.expr);
956 val2 = expr_calc_value(e->right.expr);
957 return EXPR_OR(val1, val2);
958 case E_NOT:
959 val1 = expr_calc_value(e->left.expr);
960 return EXPR_NOT(val1);
961 case E_EQUAL:
962 sym_calc_value(e->left.sym);
963 sym_calc_value(e->right.sym);
964 str1 = sym_get_string_value(e->left.sym);
965 str2 = sym_get_string_value(e->right.sym);
966 return !strcmp(str1, str2) ? yes : no;
967 case E_UNEQUAL:
968 sym_calc_value(e->left.sym);
969 sym_calc_value(e->right.sym);
970 str1 = sym_get_string_value(e->left.sym);
971 str2 = sym_get_string_value(e->right.sym);
972 return !strcmp(str1, str2) ? no : yes;
973 default:
974 printf("expr_calc_value: %d?\n", e->type);
975 return no;
976 }
977}
978
979int expr_compare_type(enum expr_type t1, enum expr_type t2)
980{
981#if 0
982 return 1;
983#else
984 if (t1 == t2)
985 return 0;
986 switch (t1) {
987 case E_EQUAL:
988 case E_UNEQUAL:
989 if (t2 == E_NOT)
990 return 1;
991 case E_NOT:
992 if (t2 == E_AND)
993 return 1;
994 case E_AND:
995 if (t2 == E_OR)
996 return 1;
997 case E_OR:
998 if (t2 == E_LIST)
999 return 1;
1000 case E_LIST:
1001 if (t2 == 0)
1002 return 1;
1003 default:
1004 return -1;
1005 }
1006 printf("[%dgt%d?]", t1, t2);
1007 return 0;
1008#endif
1009}
1010
1011static inline struct expr *
1012expr_get_leftmost_symbol(const struct expr *e)
1013{
1014
1015 if (e == NULL)
1016 return NULL;
1017
1018 while (e->type != E_SYMBOL)
1019 e = e->left.expr;
1020
1021 return expr_copy(e);
1022}
1023
1024/*
1025 * Given expression `e1' and `e2', returns the leaf of the longest
1026 * sub-expression of `e1' not containing 'e2.
1027 */
1028struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2)
1029{
1030 struct expr *ret;
1031
1032 switch (e1->type) {
1033 case E_OR:
1034 return expr_alloc_and(
1035 expr_simplify_unmet_dep(e1->left.expr, e2),
1036 expr_simplify_unmet_dep(e1->right.expr, e2));
1037 case E_AND: {
1038 struct expr *e;
1039 e = expr_alloc_and(expr_copy(e1), expr_copy(e2));
1040 e = expr_eliminate_dups(e);
1041 ret = (!expr_eq(e, e1)) ? e1 : NULL;
1042 expr_free(e);
1043 break;
1044 }
1045 default:
1046 ret = e1;
1047 break;
1048 }
1049
1050 return expr_get_leftmost_symbol(ret);
1051}
1052
1053void expr_print(struct expr *e, void (*fn)(void *, struct symbol *, const char *), void *data, int prevtoken)
1054{
1055 if (!e) {
1056 fn(data, NULL, "y");
1057 return;
1058 }
1059
1060 if (expr_compare_type(prevtoken, e->type) > 0)
1061 fn(data, NULL, "(");
1062 switch (e->type) {
1063 case E_SYMBOL:
1064 if (e->left.sym->name)
1065 fn(data, e->left.sym, e->left.sym->name);
1066 else
1067 fn(data, NULL, "<choice>");
1068 break;
1069 case E_NOT:
1070 fn(data, NULL, "!");
1071 expr_print(e->left.expr, fn, data, E_NOT);
1072 break;
1073 case E_EQUAL:
1074 if (e->left.sym->name)
1075 fn(data, e->left.sym, e->left.sym->name);
1076 else
1077 fn(data, NULL, "<choice>");
1078 fn(data, NULL, "=");
1079 fn(data, e->right.sym, e->right.sym->name);
1080 break;
1081 case E_UNEQUAL:
1082 if (e->left.sym->name)
1083 fn(data, e->left.sym, e->left.sym->name);
1084 else
1085 fn(data, NULL, "<choice>");
1086 fn(data, NULL, "!=");
1087 fn(data, e->right.sym, e->right.sym->name);
1088 break;
1089 case E_OR:
1090 expr_print(e->left.expr, fn, data, E_OR);
1091 fn(data, NULL, " || ");
1092 expr_print(e->right.expr, fn, data, E_OR);
1093 break;
1094 case E_AND:
1095 expr_print(e->left.expr, fn, data, E_AND);
1096 fn(data, NULL, " && ");
1097 expr_print(e->right.expr, fn, data, E_AND);
1098 break;
1099 case E_LIST:
1100 fn(data, e->right.sym, e->right.sym->name);
1101 if (e->left.expr) {
1102 fn(data, NULL, " ^ ");
1103 expr_print(e->left.expr, fn, data, E_LIST);
1104 }
1105 break;
1106 case E_RANGE:
1107 fn(data, NULL, "[");
1108 fn(data, e->left.sym, e->left.sym->name);
1109 fn(data, NULL, " ");
1110 fn(data, e->right.sym, e->right.sym->name);
1111 fn(data, NULL, "]");
1112 break;
1113 default:
1114 {
1115 char buf[32];
1116 sprintf(buf, "<unknown type %d>", e->type);
1117 fn(data, NULL, buf);
1118 break;
1119 }
1120 }
1121 if (expr_compare_type(prevtoken, e->type) > 0)
1122 fn(data, NULL, ")");
1123}
1124
1125static void expr_print_file_helper(void *data, struct symbol *sym, const char *str)
1126{
1127 xfwrite(str, strlen(str), 1, data);
1128}
1129
1130void expr_fprint(struct expr *e, FILE *out)
1131{
1132 expr_print(e, expr_print_file_helper, out, E_NONE);
1133}
1134
1135static void expr_print_gstr_helper(void *data, struct symbol *sym, const char *str)
1136{
1137 struct gstr *gs = (struct gstr*)data;
1138 const char *sym_str = NULL;
1139
1140 if (sym)
1141 sym_str = sym_get_string_value(sym);
1142
1143 if (gs->max_width) {
1144 unsigned extra_length = strlen(str);
1145 const char *last_cr = strrchr(gs->s, '\n');
1146 unsigned last_line_length;
1147
1148 if (sym_str)
1149 extra_length += 4 + strlen(sym_str);
1150
1151 if (!last_cr)
1152 last_cr = gs->s;
1153
1154 last_line_length = strlen(gs->s) - (last_cr - gs->s);
1155
1156 if ((last_line_length + extra_length) > gs->max_width)
1157 str_append(gs, "\\\n");
1158 }
1159
1160 str_append(gs, str);
1161 if (sym && sym->type != S_UNKNOWN)
1162 str_printf(gs, " [=%s]", sym_str);
1163}
1164
1165void expr_gstr_print(struct expr *e, struct gstr *gs)
1166{
1167 expr_print(e, expr_print_gstr_helper, gs, E_NONE);
1168}