compilers/lcc-4.2/lburg/lburg.c

   1 #include <assert.h>
   2 #include <ctype.h>
   3 #include <stdarg.h>
   4 #include <stdlib.h>
   5 #include <stdio.h>
   6 #include <string.h>
   7 #include <time.h>
   8 #include "lburg.h"
   9
  10 static char rcsid[] = "$Id$";
  11 static char *prefix = "";
  12 static int Tflag = 0;
  13 static int ntnumber = 0;
  14 static Nonterm start = 0;
  15 static Term terms;
  16 static Nonterm nts;
  17 static Rule rules;
  18 static int nrules;
  19 static struct block {
  20         struct block *link;
  21 } *memlist;                     /* list of allocated blocks */
  22
  23 static char *stringf(char *fmt, ...);
  24 static void print(char *fmt, ...);
  25 static void ckreach(Nonterm p);
  26 static void emitclosure(Nonterm nts);
  27 static void emitcost(Tree t, char *v);
  28 static void emitdefs(Nonterm nts, int ntnumber);
  29 static void emitheader(void);
  30 static void emitkids(Rule rules, int nrules);
  31 static void emitnts(Rule rules, int nrules);
  32 static void emitrecalc(char *pre, Term root, Term kid);
  33 static void emitrecord(char *pre, Rule r, char *c, int cost);
  34 static void emitrule(Nonterm nts);
  35 static void emitlabel(Term terms, Nonterm start, int ntnumber);
  36 static void emitstring(Rule rules);
  37 static void emitstruct(Nonterm nts, int ntnumber);
  38 static void emittest(Tree t, char *v, char *suffix);
  39
  40 int main(int argc, char *argv[]) {
  41         int c, i;
  42         Nonterm p;
  43
  44         for (i = 1; i < argc; i++)
  45                 if (strcmp(argv[i], "-T") == 0)
  46                         Tflag = 1;
  47                 else if (strncmp(argv[i], "-p", 2) == 0 && argv[i][2])
  48                         prefix = &argv[i][2];
  49                 else if (strncmp(argv[i], "-p", 2) == 0 && i + 1 < argc)
  50                         prefix = argv[++i];
  51                 else if (*argv[i] == '-' && argv[i][1]) {
  52                         yyerror("usage: %s [-T | -p prefix]... [ [ input ] output ] \n",
  53                                 argv[0]);
  54                         exit(1);
  55                 } else if (infp == NULL) {
  56                         if (strcmp(argv[i], "-") == 0)
  57                                 infp = stdin;
  58                         else if ((infp = fopen(argv[i], "r")) == NULL) {
  59                                 yyerror("%s: can't read `%s'\n", argv[0], argv[i]);
  60                                 exit(1);
  61                         }
  62                 } else if (outfp == NULL) {
  63                         if (strcmp(argv[i], "-") == 0)
  64                                 outfp = stdout;
  65                         if ((outfp = fopen(argv[i], "w")) == NULL) {
  66                                 yyerror("%s: can't write `%s'\n", argv[0], argv[i]);
  67                                 exit(1);
  68                         }
  69                 }
  70         if (infp == NULL)
  71                 infp = stdin;
  72         if (outfp == NULL)
  73                 outfp = stdout;
  74         yyparse();
  75         if (start)
  76                 ckreach(start);
  77         for (p = nts; p; p = p->link) {
  78                 if (p->rules == NULL)
  79                         yyerror("undefined nonterminal `%s'\n", p->name);
  80                 if (!p->reached)
  81                         yyerror("can't reach nonterminal `%s'\n", p->name);
  82         }
  83         emitheader();
  84         emitdefs(nts, ntnumber);
  85         emitstruct(nts, ntnumber);
  86         emitnts(rules, nrules);
  87         emitstring(rules);
  88         emitrule(nts);
  89         emitclosure(nts);
  90         if (start)
  91                 emitlabel(terms, start, ntnumber);
  92         emitkids(rules, nrules);
  93         if (!feof(infp))
  94                 while ((c = getc(infp)) != EOF)
  95                         putc(c, outfp);
  96         while (memlist) {       /* for purify */
  97                 struct block *q = memlist->link;
  98                 free(memlist);
  99                 memlist = q;
 100         }
 101         return errcnt > 0;
 102 }
 103
 104 /* alloc - allocate nbytes or issue fatal error */
 105 void *alloc(int nbytes) {
 106         struct block *p = calloc(1, sizeof *p + nbytes);
 107
 108         if (p == NULL) {
 109                 yyerror("out of memory\n");
 110                 exit(1);
 111         }
 112         p->link = memlist;
 113         memlist = p;
 114         return p + 1;
 115 }
 116
 117 /* stringf - format and save a string */
 118 static char *stringf(char *fmt, ...) {
 119         va_list ap;
 120         char buf[512];
 121
 122         va_start(ap, fmt);
 123         vsprintf(buf, fmt, ap);
 124         va_end(ap);
 125         return strcpy(alloc(strlen(buf) + 1), buf);
 126 }
 127
 128 struct entry {
 129         union {
 130                 char *name;
 131                 struct term t;
 132                 struct nonterm nt;
 133         } sym;
 134         struct entry *link;
 135 } *table[211];
 136 #define HASHSIZE (sizeof table/sizeof table[0])
 137
 138 /* hash - return hash number for str */
 139 static unsigned hash(char *str) {
 140         unsigned h = 0;
 141
 142         while (*str)
 143                 h = (h<<1) + *str++;
 144         return h;
 145 }
 146
 147 /* lookup - lookup symbol name */
 148 static void *lookup(char *name) {
 149         struct entry *p = table[hash(name)%HASHSIZE];
 150
 151         for ( ; p; p = p->link)
 152                 if (strcmp(name, p->sym.name) == 0)
 153                         return &p->sym;
 154         return 0;
 155 }
 156
 157 /* install - install symbol name */
 158 static void *install(char *name) {
 159         struct entry *p = alloc(sizeof *p);
 160         int i = hash(name)%HASHSIZE;
 161
 162         p->sym.name = name;
 163         p->link = table[i];
 164         table[i] = p;
 165         return &p->sym;
 166 }
 167
 168 /* nonterm - create a new terminal id, if necessary */
 169 Nonterm nonterm(char *id) {
 170         Nonterm p = lookup(id), *q = &nts;
 171
 172         if (p && p->kind == NONTERM)
 173                 return p;
 174         if (p && p->kind == TERM)
 175                 yyerror("`%s' is a terminal\n", id);
 176         p = install(id);
 177         p->kind = NONTERM;
 178         p->number = ++ntnumber;
 179         if (p->number == 1)
 180                 start = p;
 181         while (*q && (*q)->number < p->number)
 182                 q = &(*q)->link;
 183         assert(*q == 0 || (*q)->number != p->number);
 184         p->link = *q;
 185         *q = p;
 186         return p;
 187 }
 188
 189 /* term - create a new terminal id with external symbol number esn */
 190 Term term(char *id, int esn) {
 191         Term p = lookup(id), *q = &terms;
 192
 193         if (p)
 194                 yyerror("redefinition of terminal `%s'\n", id);
 195         else
 196                 p = install(id);
 197         p->kind = TERM;
 198         p->esn = esn;
 199         p->arity = -1;
 200         while (*q && (*q)->esn < p->esn)
 201                 q = &(*q)->link;
 202         if (*q && (*q)->esn == p->esn)
 203                 yyerror("duplicate external symbol number `%s=%d'\n",
 204                         p->name, p->esn);
 205         p->link = *q;
 206         *q = p;
 207         return p;
 208 }
 209
 210 /* tree - create & initialize a tree node with the given fields */
 211 Tree tree(char *id, Tree left, Tree right) {
 212         Tree t = alloc(sizeof *t);
 213         Term p = lookup(id);
 214         int arity = 0;
 215
 216         if (left && right)
 217                 arity = 2;
 218         else if (left)
 219                 arity = 1;
 220         if (p == NULL && arity > 0) {
 221                 yyerror("undefined terminal `%s'\n", id);
 222                 p = term(id, -1);
 223         } else if (p == NULL && arity == 0)
 224                 p = (Term)nonterm(id);
 225         else if (p && p->kind == NONTERM && arity > 0) {
 226                 yyerror("`%s' is a nonterminal\n", id);
 227                 p = term(id, -1);
 228         }
 229         if (p->kind == TERM && p->arity == -1)
 230                 p->arity = arity;
 231         if (p->kind == TERM && arity != p->arity)
 232                 yyerror("inconsistent arity for terminal `%s'\n", id);
 233         t->op = p;
 234         t->nterms = p->kind == TERM;
 235         if ((t->left = left) != NULL)
 236                 t->nterms += left->nterms;
 237         if ((t->right = right) != NULL)
 238                 t->nterms += right->nterms;
 239         return t;
 240 }
 241
 242 /* rule - create & initialize a rule with the given fields */
 243 Rule rule(char *id, Tree pattern, char *template, char *code) {
 244         Rule r = alloc(sizeof *r), *q;
 245         Term p = pattern->op;
 246         char *end;
 247
 248         r->lhs = nonterm(id);
 249         r->packed = ++r->lhs->lhscount;
 250         for (q = &r->lhs->rules; *q; q = &(*q)->decode)
 251                 ;
 252         *q = r;
 253         r->pattern = pattern;
 254         r->ern = ++nrules;
 255         r->template = template;
 256         r->code = code;
 257         r->cost = strtol(code, &end, 10);
 258         if (*end) {
 259                 r->cost = -1;
 260                 r->code = stringf("(%s)", code);
 261         }
 262         if (p->kind == TERM) {
 263                 for (q = &p->rules; *q; q = &(*q)->next)
 264                         ;
 265                 *q = r;
 266         } else if (pattern->left == NULL && pattern->right == NULL) {
 267                 Nonterm p = pattern->op;
 268                 r->chain = p->chain;
 269                 p->chain = r;
 270                 if (r->cost == -1)
 271                         yyerror("illegal nonconstant cost `%s'\n", code);
 272         }
 273         for (q = &rules; *q; q = &(*q)->link)
 274                 ;
 275         r->link = *q;
 276         *q = r;
 277         return r;
 278 }
 279
 280 /* print - formatted output */
 281 static void print(char *fmt, ...) {
 282         va_list ap;
 283
 284         va_start(ap, fmt);
 285         for ( ; *fmt; fmt++)
 286                 if (*fmt == '%')
 287                         switch (*++fmt) {
 288                         case 'd': fprintf(outfp, "%d", va_arg(ap, int)); break;
 289                         case 's': fputs(va_arg(ap, char *), outfp); break;
 290                         case 'P': fprintf(outfp, "%s_", prefix); break;
 291                         case 'T': {
 292                                 Tree t = va_arg(ap, Tree);
 293                                 print("%S", t->op);
 294                                 if (t->left && t->right)
 295                                         print("(%T,%T)", t->left, t->right);
 296                                 else if (t->left)
 297                                         print("(%T)", t->left);
 298                                 break;
 299                                 }
 300                         case 'R': {
 301                                 Rule r = va_arg(ap, Rule);
 302                                 print("%S: %T", r->lhs, r->pattern);
 303                                 break;
 304                                 }
 305                         case 'S': {
 306                                 Term t = va_arg(ap, Term);
 307                                 fputs(t->name, outfp);
 308                                 break;
 309                                 }
 310                         case '1': case '2': case '3': case '4': case '5': {
 311                                 int n = *fmt - '0';
 312                                 while (n-- > 0)
 313                                         putc('\t', outfp);
 314                                 break;
 315                                 }
 316                         default: putc(*fmt, outfp); break;
 317                         }
 318                 else
 319                         putc(*fmt, outfp);
 320         va_end(ap);
 321 }
 322
 323 /* reach - mark all nonterminals in tree t as reachable */
 324 static void reach(Tree t) {
 325         Nonterm p = t->op;
 326
 327         if (p->kind == NONTERM)
 328                 if (!p->reached)
 329                         ckreach(p);
 330         if (t->left)
 331                 reach(t->left);
 332         if (t->right)
 333                 reach(t->right);
 334 }
 335
 336 /* ckreach - mark all nonterminals reachable from p */
 337 static void ckreach(Nonterm p) {
 338         Rule r;
 339
 340         p->reached = 1;
 341         for (r = p->rules; r; r = r->decode)
 342                 reach(r->pattern);
 343 }
 344
 345 /* emitcase - emit one case in function state */
 346 static void emitcase(Term p, int ntnumber) {
 347         Rule r;
 348
 349         print("%1case %d: /* %S */\n", p->esn, p);
 350         switch (p->arity) {
 351         case 0: case -1:
 352                 break;
 353         case 1:
 354                 print("%2%Plabel(LEFT_CHILD(a));\n");
 355                 break;
 356         case 2:
 357                 print("%2%Plabel(LEFT_CHILD(a));\n");
 358                 print("%2%Plabel(RIGHT_CHILD(a));\n");
 359                 break;
 360         default: assert(0);
 361         }
 362         for (r = p->rules; r; r = r->next) {
 363                 char *indent = "\t\t\0";
 364                 switch (p->arity) {
 365                 case 0: case -1:
 366                         print("%2/* %R */\n", r);
 367                         if (r->cost == -1) {
 368                                 print("%2c = %s;\n", r->code);
 369                                 emitrecord("\t\t", r, "c", 0);
 370                         } else
 371                                 emitrecord("\t\t", r, r->code, 0);
 372                         break;
 373                 case 1:
 374                         if (r->pattern->nterms > 1) {
 375                                 print("%2if (%1/* %R */\n", r);
 376                                 emittest(r->pattern->left, "LEFT_CHILD(a)", " ");
 377                                 print("%2) {\n");
 378                                 indent = "\t\t\t";
 379                         } else
 380                                 print("%2/* %R */\n", r);
 381                         if (r->pattern->nterms == 2 && r->pattern->left
 382                         &&  r->pattern->right == NULL)
 383                                 emitrecalc(indent, r->pattern->op, r->pattern->left->op);
 384                         print("%sc = ", indent);
 385                         emitcost(r->pattern->left, "LEFT_CHILD(a)");
 386                         print("%s;\n", r->code);
 387                         emitrecord(indent, r, "c", 0);
 388                         if (indent[2])
 389                                 print("%2}\n");
 390                         break;
 391                 case 2:
 392                         if (r->pattern->nterms > 1) {
 393                                 print("%2if (%1/* %R */\n", r);
 394                                 emittest(r->pattern->left,  "LEFT_CHILD(a)",
 395                                         r->pattern->right->nterms ? " && " : " ");
 396                                 emittest(r->pattern->right, "RIGHT_CHILD(a)", " ");
 397                                 print("%2) {\n");
 398                                 indent = "\t\t\t";
 399                         } else
 400                                 print("%2/* %R */\n", r);
 401                         print("%sc = ", indent);
 402                         emitcost(r->pattern->left,  "LEFT_CHILD(a)");
 403                         emitcost(r->pattern->right, "RIGHT_CHILD(a)");
 404                         print("%s;\n", r->code);
 405                         emitrecord(indent, r, "c", 0);
 406                         if (indent[2])
 407                                 print("%2}\n");
 408                         break;
 409                 default: assert(0);
 410                 }
 411         }
 412         print("%2break;\n");
 413 }
 414
 415 /* emitclosure - emit the closure functions */
 416 static void emitclosure(Nonterm nts) {
 417         Nonterm p;
 418
 419         for (p = nts; p; p = p->link)
 420                 if (p->chain)
 421                         print("static void %Pclosure_%S(NODEPTR_TYPE, int);\n", p);
 422         print("\n");
 423         for (p = nts; p; p = p->link)
 424                 if (p->chain) {
 425                         Rule r;
 426                         print("static void %Pclosure_%S(NODEPTR_TYPE a, int c) {\n"
 427 "%1struct %Pstate *p = STATE_LABEL(a);\n", p);
 428                         for (r = p->chain; r; r = r->chain)
 429                                 emitrecord("\t", r, "c", r->cost);
 430                         print("}\n\n");
 431                 }
 432 }
 433
 434 /* emitcost - emit cost computation for tree t */
 435 static void emitcost(Tree t, char *v) {
 436         Nonterm p = t->op;
 437
 438         if (p->kind == TERM) {
 439                 if (t->left)
 440                         emitcost(t->left,  stringf("LEFT_CHILD(%s)",  v));
 441                 if (t->right)
 442                         emitcost(t->right, stringf("RIGHT_CHILD(%s)", v));
 443         } else
 444                 print("((struct %Pstate *)(%s->x.state))->cost[%P%S_NT] + ", v, p);
 445 }
 446
 447 /* emitdefs - emit nonterminal defines and data structures */
 448 static void emitdefs(Nonterm nts, int ntnumber) {
 449         Nonterm p;
 450
 451         for (p = nts; p; p = p->link)
 452                 print("#define %P%S_NT %d\n", p, p->number);
 453         print("\n");
 454         print("static char *%Pntname[] = {\n%10,\n");
 455         for (p = nts; p; p = p->link)
 456                 print("%1\"%S\",\n", p);
 457         print("%10\n};\n\n");
 458 }
 459
 460 /* emitheader - emit initial definitions */
 461 static void emitheader(void) {
 462         time_t timer = time(NULL);
 463
 464         print("/*\ngenerated at %sby %s\n*/\n", ctime(&timer), rcsid);
 465         print("static void %Pkids(NODEPTR_TYPE, int, NODEPTR_TYPE[]);\n");
 466         print("static void %Plabel(NODEPTR_TYPE);\n");
 467         print("static int %Prule(void*, int);\n\n");
 468 }
 469
 470 /* computekids - compute paths to kids in tree t */
 471 static char *computekids(Tree t, char *v, char *bp, int *ip) {
 472         Term p = t->op;
 473
 474         if (p->kind == NONTERM) {
 475                 sprintf(bp, "\t\tkids[%d] = %s;\n", (*ip)++, v);
 476                 bp += strlen(bp);
 477         } else if (p->arity > 0) {
 478                 bp = computekids(t->left, stringf("LEFT_CHILD(%s)", v), bp, ip);
 479                 if (p->arity == 2)
 480                         bp = computekids(t->right, stringf("RIGHT_CHILD(%s)", v), bp, ip);
 481         }
 482         return bp;
 483 }
 484
 485 /* emitkids - emit _kids */
 486 static void emitkids(Rule rules, int nrules) {
 487         int i;
 488         Rule r, *rc = alloc((nrules + 1 + 1)*sizeof *rc);
 489         char **str  = alloc((nrules + 1 + 1)*sizeof *str);
 490
 491         for (i = 0, r = rules; r; r = r->link) {
 492                 int j = 0;
 493                 char buf[1024], *bp = buf;
 494                 *computekids(r->pattern, "p", bp, &j) = 0;
 495                 for (j = 0; str[j] && strcmp(str[j], buf); j++)
 496                         ;
 497                 if (str[j] == NULL)
 498                         str[j] = strcpy(alloc(strlen(buf) + 1), buf);
 499                 r->kids = rc[j];
 500                 rc[j] = r;
 501         }
 502         print("static void %Pkids(NODEPTR_TYPE p, int eruleno, NODEPTR_TYPE kids[]) {\n"
 503 "%1if (!p)\n%2fatal(\"%Pkids\", \"Null tree\\n\", 0);\n"
 504 "%1if (!kids)\n%2fatal(\"%Pkids\", \"Null kids\\n\", 0);\n"
 505 "%1switch (eruleno) {\n");
 506         for (i = 0; (r = rc[i]) != NULL; i++) {
 507                 for ( ; r; r = r->kids)
 508                         print("%1case %d: /* %R */\n", r->ern, r);
 509                 print("%s%2break;\n", str[i]);
 510         }
 511         print("%1default:\n%2fatal(\"%Pkids\", \"Bad rule number %%d\\n\", eruleno);\n%1}\n}\n\n");
 512 }
 513
 514 /* emitlabel - emit label function */
 515 static void emitlabel(Term terms, Nonterm start, int ntnumber) {
 516         int i;
 517         Term p;
 518
 519         print("static void %Plabel(NODEPTR_TYPE a) {\n%1int c;\n"
 520 "%1struct %Pstate *p;\n\n"
 521 "%1if (!a)\n%2fatal(\"%Plabel\", \"Null tree\\n\", 0);\n");
 522         print("%1STATE_LABEL(a) = p = allocate(sizeof *p, FUNC);\n"
 523 "%1p->rule._stmt = 0;\n");
 524         for (i = 1; i <= ntnumber; i++)
 525                 print("%1p->cost[%d] =\n", i);
 526         print("%20x7fff;\n%1switch (OP_LABEL(a)) {\n");
 527         for (p = terms; p; p = p->link)
 528                 emitcase(p, ntnumber);
 529         print("%1default:\n"
 530 "%2fatal(\"%Plabel\", \"Bad terminal %%d\\n\", OP_LABEL(a));\n%1}\n}\n\n");
 531 }
 532
 533 /* computents - fill in bp with _nts vector for tree t */
 534 static char *computents(Tree t, char *bp) {
 535         if (t) {
 536                 Nonterm p = t->op;
 537                 if (p->kind == NONTERM) {
 538                         sprintf(bp, "%s_%s_NT, ", prefix, p->name);
 539                         bp += strlen(bp);
 540                 } else
 541                         bp = computents(t->right, computents(t->left,  bp));
 542         }
 543         return bp;
 544 }
 545
 546 /* emitnts - emit _nts ragged array */
 547 static void emitnts(Rule rules, int nrules) {
 548         Rule r;
 549         int i, j, *nts = alloc((nrules + 1)*sizeof *nts);
 550         char **str = alloc((nrules + 1)*sizeof *str);
 551
 552         for (i = 0, r = rules; r; r = r->link) {
 553                 char buf[1024];
 554                 *computents(r->pattern, buf) = 0;
 555                 for (j = 0; str[j] && strcmp(str[j], buf); j++)
 556                         ;
 557                 if (str[j] == NULL) {
 558                         print("static short %Pnts_%d[] = { %s0 };\n", j, buf);
 559                         str[j] = strcpy(alloc(strlen(buf) + 1), buf);
 560                 }
 561                 nts[i++] = j;
 562         }
 563         print("\nstatic short *%Pnts[] = {\n");
 564         for (i = j = 0, r = rules; r; r = r->link) {
 565                 for ( ; j < r->ern; j++)
 566                         print("%10,%1/* %d */\n", j);
 567                 print("%1%Pnts_%d,%1/* %d */\n", nts[i++], j++);
 568         }
 569         print("};\n\n");
 570 }
 571
 572 /* emitrecalc - emit code that tests for recalculation of INDIR?(VREGP) */
 573 static void emitrecalc(char *pre, Term root, Term kid) {
 574         if (root->kind == TERM && strncmp(root->name, "INDIR", 5) == 0
 575         &&   kid->kind == TERM &&  strcmp(kid->name,  "VREGP"   ) == 0) {
 576                 Nonterm p;
 577                 print("%sif (mayrecalc(a)) {\n", pre);
 578                 print("%s%1struct %Pstate *q = a->syms[RX]->u.t.cse->x.state;\n", pre);
 579                 for (p = nts; p; p = p->link) {
 580                         print("%s%1if (q->cost[%P%S_NT] == 0) {\n", pre, p);
 581                         print("%s%2p->cost[%P%S_NT] = 0;\n", pre, p);
 582                         print("%s%2p->rule.%P%S = q->rule.%P%S;\n", pre, p, p);
 583                         print("%s%1}\n", pre);
 584                 }
 585                 print("%s}\n", pre);
 586         }
 587 }
 588
 589 /* emitrecord - emit code that tests for a winning match of rule r */
 590 static void emitrecord(char *pre, Rule r, char *c, int cost) {
 591         if (Tflag)
 592                 print("%s%Ptrace(a, %d, %s + %d, p->cost[%P%S_NT]);\n",
 593                         pre, r->ern, c, cost, r->lhs);
 594         print("%sif (", pre);
 595         print("%s + %d < p->cost[%P%S_NT]) {\n"
 596 "%s%1p->cost[%P%S_NT] = %s + %d;\n%s%1p->rule.%P%S = %d;\n",
 597                 c, cost, r->lhs, pre, r->lhs, c, cost, pre, r->lhs,
 598                 r->packed);
 599         if (r->lhs->chain)
 600                 print("%s%1%Pclosure_%S(a, %s + %d);\n", pre, r->lhs, c, cost);
 601         print("%s}\n", pre);
 602 }
 603
 604 /* emitrule - emit decoding vectors and _rule */
 605 static void emitrule(Nonterm nts) {
 606         Nonterm p;
 607
 608         for (p = nts; p; p = p->link) {
 609                 Rule r;
 610                 print("static short %Pdecode_%S[] = {\n%10,\n", p);
 611                 for (r = p->rules; r; r = r->decode)
 612                         print("%1%d,\n", r->ern);
 613                 print("};\n\n");
 614         }
 615         print("static int %Prule(void *state, int goalnt) {\n"
 616 "%1if (goalnt < 1 || goalnt > %d)\n%2fatal(\"%Prule\", \"Bad goal nonterminal %%d\\n\", goalnt);\n"
 617 "%1if (!state)\n%2return 0;\n%1switch (goalnt) {\n", ntnumber);
 618         for (p = nts; p; p = p->link)
 619                 print("%1case %P%S_NT:"
 620 "%1return %Pdecode_%S[((struct %Pstate *)state)->rule.%P%S];\n", p, p, p);
 621         print("%1default:\n%2fatal(\"%Prule\", \"Bad goal nonterminal %%d\\n\", goalnt);\n%2return 0;\n%1}\n}\n\n");
 622 }
 623
 624 /* emitstring - emit arrays of templates, instruction flags, and rules */
 625 static void emitstring(Rule rules) {
 626         Rule r;
 627
 628         print("static char *%Ptemplates[] = {\n");
 629         print("/* 0 */%10,\n");
 630         for (r = rules; r; r = r->link)
 631                 print("/* %d */%1\"%s\",%1/* %R */\n", r->ern, r->template, r);
 632         print("};\n");
 633         print("\nstatic char %Pisinstruction[] = {\n");
 634         print("/* 0 */%10,\n");
 635         for (r = rules; r; r = r->link) {
 636                 int len = strlen(r->template);
 637                 print("/* %d */%1%d,%1/* %s */\n", r->ern,
 638                         len >= 2 && r->template[len-2] == '\\' && r->template[len-1] == 'n',
 639                         r->template);
 640         }
 641         print("};\n");
 642         print("\nstatic char *%Pstring[] = {\n");
 643         print("/* 0 */%10,\n");
 644         for (r = rules; r; r = r->link)
 645                 print("/* %d */%1\"%R\",\n", r->ern, r);
 646         print("};\n\n");
 647 }
 648
 649 /* emitstruct - emit the definition of the state structure */
 650 static void emitstruct(Nonterm nts, int ntnumber) {
 651         print("struct %Pstate {\n%1short cost[%d];\n%1struct {\n", ntnumber + 1);
 652         for ( ; nts; nts = nts->link) {
 653                 int n = 1, m = nts->lhscount;
 654                 while ((m >>= 1) != 0)
 655                         n++;
 656                 print("%2unsigned int %P%S:%d;\n", nts, n);
 657         }
 658         print("%1} rule;\n};\n\n");
 659 }
 660
 661 /* emittest - emit clause for testing a match */
 662 static void emittest(Tree t, char *v, char *suffix) {
 663         Term p = t->op;
 664
 665         if (p->kind == TERM) {
 666                 print("%3%s->op == %d%s/* %S */\n", v, p->esn,
 667                         t->nterms > 1 ? " && " : suffix, p);
 668                 if (t->left)
 669                         emittest(t->left, stringf("LEFT_CHILD(%s)",  v),
 670                                 t->right && t->right->nterms ? " && " : suffix);
 671                 if (t->right)
 672                         emittest(t->right, stringf("RIGHT_CHILD(%s)", v), suffix);
 673         }
 674 }