sys/src/cmd/6l/pass.c

   1 #include        "l.h"
   2
   3 void
   4 dodata(void)
   5 {
   6         int i;
   7         Sym *s;
   8         Prog *p;
   9         long t, u;
  10
  11         if(debug['v'])
  12                 Bprint(&bso, "%5.2f dodata\n", cputime());
  13         Bflush(&bso);
  14         for(p = datap; p != P; p = p->link) {
  15                 s = p->from.sym;
  16                 if(p->as == ADYNT || p->as == AINIT)
  17                         s->value = dtype;
  18                 if(s->type == SBSS)
  19                         s->type = SDATA;
  20                 if(s->type != SDATA)
  21                         diag("initialize non-data (%d): %s\n%P",
  22                                 s->type, s->name, p);
  23                 t = p->from.offset + p->width;
  24                 if(t > s->value)
  25                         diag("initialize bounds (%lld): %s\n%P",
  26                                 s->value, s->name, p);
  27         }
  28         /* allocate small guys */
  29         datsize = 0;
  30         for(i=0; i<NHASH; i++)
  31         for(s = hash[i]; s != S; s = s->link) {
  32                 if(s->type != SDATA)
  33                 if(s->type != SBSS)
  34                         continue;
  35                 t = s->value;
  36                 if(t == 0) {
  37                         diag("%s: no size", s->name);
  38                         t = 1;
  39                 }
  40                 t = rnd(t, 4);
  41                 s->value = t;
  42                 if(t > MINSIZ)
  43                         continue;
  44                 if(t >= 8)
  45                         datsize = rnd(datsize, 8);
  46                 s->value = datsize;
  47                 datsize += t;
  48                 s->type = SDATA1;
  49         }
  50
  51         /* allocate the rest of the data */
  52         for(i=0; i<NHASH; i++)
  53         for(s = hash[i]; s != S; s = s->link) {
  54                 if(s->type != SDATA) {
  55                         if(s->type == SDATA1)
  56                                 s->type = SDATA;
  57                         continue;
  58                 }
  59                 t = s->value;
  60                 if(t >= 8)
  61                         datsize = rnd(datsize, 8);
  62                 s->value = datsize;
  63                 datsize += t;
  64         }
  65         if(datsize)
  66                 datsize = rnd(datsize, 8);
  67
  68         if(debug['j']) {
  69                 /*
  70                  * pad data with bss that fits up to next
  71                  * 8k boundary, then push data to 8k
  72                  */
  73                 u = rnd(datsize, 8192);
  74                 u -= datsize;
  75                 for(i=0; i<NHASH; i++)
  76                 for(s = hash[i]; s != S; s = s->link) {
  77                         if(s->type != SBSS)
  78                                 continue;
  79                         t = s->value;
  80                         if(t > u)
  81                                 continue;
  82                         u -= t;
  83                         s->value = datsize;
  84                         s->type = SDATA;
  85                         datsize += t;
  86                 }
  87                 datsize += u;
  88         }
  89
  90         /* now the bss */
  91         bsssize = 0;
  92         for(i=0; i<NHASH; i++)
  93         for(s = hash[i]; s != S; s = s->link) {
  94                 if(s->type != SBSS)
  95                         continue;
  96                 t = s->value;
  97                 if(t >= 8)
  98                         bsssize = rnd(bsssize, 8);
  99                 s->value = bsssize + datsize;
 100                 bsssize += t;
 101         }
 102         xdefine("edata", SBSS, datsize);
 103         xdefine("end", SBSS, bsssize + datsize);
 104 }
 105
 106 Prog*
 107 brchain(Prog *p)
 108 {
 109         int i;
 110
 111         for(i=0; i<20; i++) {
 112                 if(p == P || p->as != AJMP)
 113                         return p;
 114                 p = p->pcond;
 115         }
 116         return P;
 117 }
 118
 119 void
 120 follow(void)
 121 {
 122
 123         if(debug['v'])
 124                 Bprint(&bso, "%5.2f follow\n", cputime());
 125         Bflush(&bso);
 126         firstp = prg();
 127         lastp = firstp;
 128         xfol(textp);
 129         lastp->link = P;
 130         firstp = firstp->link;
 131 }
 132
 133 void
 134 xfol(Prog *p)
 135 {
 136         Prog *q;
 137         int i;
 138         enum as a;
 139
 140 loop:
 141         if(p == P)
 142                 return;
 143         if(p->as == ATEXT)
 144                 curtext = p;
 145         if(p->as == AJMP)
 146         if((q = p->pcond) != P) {
 147                 p->mark = 1;
 148                 p = q;
 149                 if(p->mark == 0)
 150                         goto loop;
 151         }
 152         if(p->mark) {
 153                 /* copy up to 4 instructions to avoid branch */
 154                 for(i=0,q=p; i<4; i++,q=q->link) {
 155                         if(q == P)
 156                                 break;
 157                         if(q == lastp)
 158                                 break;
 159                         a = q->as;
 160                         if(a == ANOP) {
 161                                 i--;
 162                                 continue;
 163                         }
 164                         switch(a) {
 165                         case AJMP:
 166                         case ARET:
 167                         case AIRETL:
 168                         case AIRETQ:
 169                         case AIRETW:
 170                         case ARETFL:
 171                         case ARETFQ:
 172                         case ARETFW:
 173
 174                         case APUSHL:
 175                         case APUSHFL:
 176                         case APUSHQ:
 177                         case APUSHFQ:
 178                         case APUSHW:
 179                         case APUSHFW:
 180                         case APOPL:
 181                         case APOPFL:
 182                         case APOPQ:
 183                         case APOPFQ:
 184                         case APOPW:
 185                         case APOPFW:
 186                                 goto brk;
 187                         }
 188                         if(q->pcond == P || q->pcond->mark)
 189                                 continue;
 190                         if(a == ACALL || a == ALOOP)
 191                                 continue;
 192                         for(;;) {
 193                                 if(p->as == ANOP) {
 194                                         p = p->link;
 195                                         continue;
 196                                 }
 197                                 q = copyp(p);
 198                                 p = p->link;
 199                                 q->mark = 1;
 200                                 lastp->link = q;
 201                                 lastp = q;
 202                                 if(q->as != a || q->pcond == P || q->pcond->mark)
 203                                         continue;
 204
 205                                 q->as = relinv(q->as);
 206                                 p = q->pcond;
 207                                 q->pcond = q->link;
 208                                 q->link = p;
 209                                 xfol(q->link);
 210                                 p = q->link;
 211                                 if(p->mark)
 212                                         return;
 213                                 goto loop;
 214                         }
 215                 } /* */
 216         brk:;
 217                 q = prg();
 218                 q->as = AJMP;
 219                 q->line = p->line;
 220                 q->to.type = D_BRANCH;
 221                 q->to.offset = p->pc;
 222                 q->pcond = p;
 223                 p = q;
 224         }
 225         p->mark = 1;
 226         lastp->link = p;
 227         lastp = p;
 228         a = p->as;
 229         if(a == AJMP || a == ARET || a == AIRETL || a == AIRETQ || a == AIRETW ||
 230            a == ARETFL || a == ARETFQ || a == ARETFW)
 231                 return;
 232         if(p->pcond != P)
 233         if(a != ACALL) {
 234                 q = brchain(p->link);
 235                 if(q != P && q->mark)
 236                 if(a != ALOOP && a != ATEXT) {
 237                         p->as = relinv(a);
 238                         p->link = p->pcond;
 239                         p->pcond = q;
 240                 }
 241                 xfol(p->link);
 242                 q = brchain(p->pcond);
 243                 if(q->mark) {
 244                         p->pcond = q;
 245                         return;
 246                 }
 247                 p = q;
 248                 goto loop;
 249         }
 250         p = p->link;
 251         goto loop;
 252 }
 253
 254 int
 255 relinv(int a)
 256 {
 257
 258         switch(a) {
 259         case AJEQ:      return AJNE;
 260         case AJNE:      return AJEQ;
 261         case AJLE:      return AJGT;
 262         case AJLS:      return AJHI;
 263         case AJLT:      return AJGE;
 264         case AJMI:      return AJPL;
 265         case AJGE:      return AJLT;
 266         case AJPL:      return AJMI;
 267         case AJGT:      return AJLE;
 268         case AJHI:      return AJLS;
 269         case AJCS:      return AJCC;
 270         case AJCC:      return AJCS;
 271         case AJPS:      return AJPC;
 272         case AJPC:      return AJPS;
 273         case AJOS:      return AJOC;
 274         case AJOC:      return AJOS;
 275         }
 276         diag("unknown relation: %s in %s", anames[a], TNAME);
 277         return a;
 278 }
 279
 280 void
 281 doinit(void)
 282 {
 283         Sym *s;
 284         Prog *p;
 285         int x;
 286
 287         for(p = datap; p != P; p = p->link) {
 288                 x = p->to.type;
 289                 if(x != D_EXTERN && x != D_STATIC)
 290                         continue;
 291                 s = p->to.sym;
 292                 if(s->type == 0 || s->type == SXREF)
 293                         diag("undefined %s initializer of %s",
 294                                 s->name, p->from.sym->name);
 295                 p->to.offset += s->value;
 296                 p->to.type = D_CONST;
 297                 if(s->type == SDATA || s->type == SBSS)
 298                         p->to.offset += INITDAT;
 299         }
 300 }
 301
 302 void
 303 patch(void)
 304 {
 305         long c;
 306         Prog *p, *q;
 307         Sym *s;
 308         long vexit;
 309
 310         if(debug['v'])
 311                 Bprint(&bso, "%5.2f mkfwd\n", cputime());
 312         Bflush(&bso);
 313         mkfwd();
 314         if(debug['v'])
 315                 Bprint(&bso, "%5.2f patch\n", cputime());
 316         Bflush(&bso);
 317         s = lookup("exit", 0);
 318         vexit = s->value;
 319         for(p = firstp; p != P; p = p->link) {
 320                 if(p->as == ATEXT)
 321                         curtext = p;
 322                 if(p->as == ACALL || p->as == ARET) {
 323                         s = p->to.sym;
 324                         if(s) {
 325                                 if(debug['c'])
 326                                         Bprint(&bso, "%s calls %s\n", TNAME, s->name);
 327                                 switch(s->type) {
 328                                 default:
 329                                         diag("undefined: %s in %s", s->name, TNAME);
 330                                         s->type = STEXT;
 331                                         s->value = vexit;
 332                                         break;  /* or fall through to set offset? */
 333                                 case STEXT:
 334                                         p->to.offset = s->value;
 335                                         break;
 336                                 case SUNDEF:
 337                                         p->pcond = UP;
 338                                         p->to.offset = 0;
 339                                         break;
 340                                 }
 341                                 p->to.type = D_BRANCH;
 342                         }
 343                 }
 344                 if(p->to.type != D_BRANCH || p->pcond == UP)
 345                         continue;
 346                 c = p->to.offset;
 347                 for(q = firstp; q != P;) {
 348                         if(q->forwd != P)
 349                         if(c >= q->forwd->pc) {
 350                                 q = q->forwd;
 351                                 continue;
 352                         }
 353                         if(c == q->pc)
 354                                 break;
 355                         q = q->link;
 356                 }
 357                 if(q == P) {
 358                         diag("branch out of range in %s\n%P", TNAME, p);
 359                         p->to.type = D_NONE;
 360                 }
 361                 p->pcond = q;
 362         }
 363
 364         for(p = firstp; p != P; p = p->link) {
 365                 if(p->as == ATEXT)
 366                         curtext = p;
 367                 p->mark = 0;    /* initialization for follow */
 368                 if(p->pcond != P && p->pcond != UP) {
 369                         p->pcond = brloop(p->pcond);
 370                         if(p->pcond != P)
 371                         if(p->to.type == D_BRANCH)
 372                                 p->to.offset = p->pcond->pc;
 373                 }
 374         }
 375 }
 376
 377 #define LOG     5
 378 void
 379 mkfwd(void)
 380 {
 381         Prog *p;
 382         int i;
 383         long dwn[LOG], cnt[LOG];
 384         Prog *lst[LOG];
 385
 386         for(i=0; i<LOG; i++) {
 387                 if(i == 0)
 388                         cnt[i] = 1; else
 389                         cnt[i] = LOG * cnt[i-1];
 390                 dwn[i] = 1;
 391                 lst[i] = P;
 392         }
 393         i = 0;
 394         for(p = firstp; p != P; p = p->link) {
 395                 if(p->as == ATEXT)
 396                         curtext = p;
 397                 i--;
 398                 if(i < 0)
 399                         i = LOG-1;
 400                 p->forwd = P;
 401                 dwn[i]--;
 402                 if(dwn[i] <= 0) {
 403                         dwn[i] = cnt[i];
 404                         if(lst[i] != P)
 405                                 lst[i]->forwd = p;
 406                         lst[i] = p;
 407                 }
 408         }
 409 }
 410
 411 Prog*
 412 brloop(Prog *p)
 413 {
 414         int c;
 415         Prog *q;
 416
 417         c = 0;
 418         for(q = p; q != P; q = q->pcond) {
 419                 if(q->as != AJMP)
 420                         break;
 421                 c++;
 422                 if(c >= 5000)
 423                         return P;
 424         }
 425         return q;
 426 }
 427
 428 void
 429 dostkoff(void)
 430 {
 431         Prog *p, *q;
 432         long autoffset, deltasp;
 433         int a, f, curframe, curbecome, maxbecome, pcsize;
 434
 435         curframe = 0;
 436         curbecome = 0;
 437         maxbecome = 0;
 438         curtext = 0;
 439         for(p = firstp; p != P; p = p->link) {
 440
 441                 /* find out how much arg space is used in this TEXT */
 442                 if(p->to.type == (D_INDIR+D_SP))
 443                         if(p->to.offset > curframe)
 444                                 curframe = p->to.offset;
 445
 446                 switch(p->as) {
 447                 case ATEXT:
 448                         if(curtext && curtext->from.sym) {
 449                                 curtext->from.sym->frame = curframe;
 450                                 curtext->from.sym->become = curbecome;
 451                                 if(curbecome > maxbecome)
 452                                         maxbecome = curbecome;
 453                         }
 454                         curframe = 0;
 455                         curbecome = 0;
 456
 457                         curtext = p;
 458                         break;
 459
 460                 case ARET:
 461                         /* special form of RET is BECOME */
 462                         if(p->from.type == D_CONST)
 463                                 if(p->from.offset > curbecome)
 464                                         curbecome = p->from.offset;
 465                         break;
 466                 }
 467         }
 468         if(curtext && curtext->from.sym) {
 469                 curtext->from.sym->frame = curframe;
 470                 curtext->from.sym->become = curbecome;
 471                 if(curbecome > maxbecome)
 472                         maxbecome = curbecome;
 473         }
 474
 475         if(debug['b'])
 476                 print("max become = %d\n", maxbecome);
 477         xdefine("ALEFbecome", STEXT, maxbecome);
 478
 479         curtext = 0;
 480         for(p = firstp; p != P; p = p->link) {
 481                 switch(p->as) {
 482                 case ATEXT:
 483                         curtext = p;
 484                         break;
 485                 case ACALL:
 486                         if(curtext != P && curtext->from.sym != S && curtext->to.offset >= 0) {
 487                                 f = maxbecome - curtext->from.sym->frame;
 488                                 if(f <= 0)
 489                                         break;
 490                                 /* calling a become or calling a variable */
 491                                 if(p->to.sym == S || p->to.sym->become) {
 492                                         curtext->to.offset += f;
 493                                         if(debug['b']) {
 494                                                 curp = p;
 495                                                 print("%D calling %D increase %d\n",
 496                                                         &curtext->from, &p->to, f);
 497                                         }
 498                                 }
 499                         }
 500                         break;
 501                 }
 502         }
 503
 504         autoffset = 0;
 505         deltasp = 0;
 506         for(p = firstp; p != P; p = p->link) {
 507                 if(p->as == ATEXT) {
 508                         curtext = p;
 509                         autoffset = p->to.offset;
 510                         if(autoffset < 0) {
 511                                 autoffset = 0;
 512                                 p->to.offset = 0;
 513                         }
 514                         if(autoffset) {
 515                                 p = appendp(p);
 516                                 p->as = AADJSP;
 517                                 p->from.type = D_CONST;
 518                                 p->from.offset = autoffset;
 519                         }
 520                         deltasp = autoffset;
 521                 }
 522                 pcsize = p->mode/8;
 523                 a = p->from.type;
 524                 if(a == D_AUTO)
 525                         p->from.offset += deltasp;
 526                 if(a == D_PARAM)
 527                         p->from.offset += deltasp + pcsize;
 528                 a = p->to.type;
 529                 if(a == D_AUTO)
 530                         p->to.offset += deltasp;
 531                 if(a == D_PARAM)
 532                         p->to.offset += deltasp + pcsize;
 533
 534                 switch(p->as) {
 535                 default:
 536                         continue;
 537                 case APUSHL:
 538                 case APUSHFL:
 539                         deltasp += 4;
 540                         continue;
 541                 case APUSHQ:
 542                 case APUSHFQ:
 543                         deltasp += 8;
 544                         continue;
 545                 case APUSHW:
 546                 case APUSHFW:
 547                         deltasp += 2;
 548                         continue;
 549                 case APOPL:
 550                 case APOPFL:
 551                         deltasp -= 4;
 552                         continue;
 553                 case APOPQ:
 554                 case APOPFQ:
 555                         deltasp -= 8;
 556                         continue;
 557                 case APOPW:
 558                 case APOPFW:
 559                         deltasp -= 2;
 560                         continue;
 561                 case ARET:
 562                         break;
 563                 }
 564
 565                 if(autoffset != deltasp)
 566                         diag("unbalanced PUSH/POP");
 567                 if(p->from.type == D_CONST)
 568                         goto become;
 569
 570                 if(autoffset) {
 571                         q = p;
 572                         p = appendp(p);
 573                         p->as = ARET;
 574
 575                         q->as = AADJSP;
 576                         q->from.type = D_CONST;
 577                         q->from.offset = -autoffset;
 578                 }
 579                 continue;
 580
 581         become:
 582                 q = p;
 583                 p = appendp(p);
 584                 p->as = AJMP;
 585                 p->to = q->to;
 586                 p->pcond = q->pcond;
 587
 588                 q->as = AADJSP;
 589                 q->from = zprg.from;
 590                 q->from.type = D_CONST;
 591                 q->from.offset = -autoffset;
 592                 q->to = zprg.to;
 593                 continue;
 594         }
 595 }
 596
 597 vlong
 598 atolwhex(char *s)
 599 {
 600         vlong n;
 601         int f;
 602
 603         n = 0;
 604         f = 0;
 605         while(*s == ' ' || *s == '\t')
 606                 s++;
 607         if(*s == '-' || *s == '+') {
 608                 if(*s++ == '-')
 609                         f = 1;
 610                 while(*s == ' ' || *s == '\t')
 611                         s++;
 612         }
 613         if(s[0]=='0' && s[1]){
 614                 if(s[1]=='x' || s[1]=='X'){
 615                         s += 2;
 616                         for(;;){
 617                                 if(*s >= '0' && *s <= '9')
 618                                         n = n*16 + *s++ - '0';
 619                                 else if(*s >= 'a' && *s <= 'f')
 620                                         n = n*16 + *s++ - 'a' + 10;
 621                                 else if(*s >= 'A' && *s <= 'F')
 622                                         n = n*16 + *s++ - 'A' + 10;
 623                                 else
 624                                         break;
 625                         }
 626                 } else
 627                         while(*s >= '0' && *s <= '7')
 628                                 n = n*8 + *s++ - '0';
 629         } else
 630                 while(*s >= '0' && *s <= '9')
 631                         n = n*10 + *s++ - '0';
 632         if(f)
 633                 n = -n;
 634         return n;
 635 }
 636
 637 void
 638 undef(void)
 639 {
 640         int i;
 641         Sym *s;
 642
 643         for(i=0; i<NHASH; i++)
 644         for(s = hash[i]; s != S; s = s->link)
 645                 if(s->type == SXREF)
 646                         diag("%s: not defined", s->name);
 647 }
 648
 649 void
 650 import(void)
 651 {
 652         int i;
 653         Sym *s;
 654
 655         for(i = 0; i < NHASH; i++)
 656                 for(s = hash[i]; s != S; s = s->link)
 657                         if(s->sig != 0 && s->type == SXREF && (nimports == 0 || s->subtype == SIMPORT)){
 658                                 if(s->value != 0)
 659                                         diag("value != 0 on SXREF");
 660                                 undefsym(s);
 661                                 Bprint(&bso, "IMPORT: %s sig=%lux v=%lld\n", s->name, s->sig, s->value);
 662                                 if(debug['S'])
 663                                         s->sig = 0;
 664                         }
 665 }
 666
 667 void
 668 ckoff(Sym *s, long v)
 669 {
 670         if(v < 0 || v >= 1<<Roffset)
 671                 diag("relocation offset %ld for %s out of range", v, s->name);
 672 }
 673
 674 static Prog*
 675 newdata(Sym *s, int o, int w, int t)
 676 {
 677         Prog *p;
 678
 679         p = prg();
 680         if(edatap == P)
 681                 datap = p;
 682         else
 683                 edatap->link = p;
 684         edatap = p;
 685         p->as = ADATA;
 686         p->width = w;
 687         p->from.scale = w;
 688         p->from.type = t;
 689         p->from.sym = s;
 690         p->from.offset = o;
 691         p->to.type = D_CONST;
 692         return p;
 693 }
 694
 695 void
 696 export(void)
 697 {
 698         int i, j, n, off, nb, sv, ne;
 699         Sym *s, *et, *str, **esyms;
 700         Prog *p;
 701         char buf[NSNAME], *t;
 702
 703         n = 0;
 704         for(i = 0; i < NHASH; i++)
 705                 for(s = hash[i]; s != S; s = s->link)
 706                         if(s->sig != 0 && s->type != SXREF && s->type != SUNDEF && (nexports == 0 || s->subtype == SEXPORT))
 707                                 n++;
 708         esyms = malloc(n*sizeof(Sym*));
 709         ne = n;
 710         n = 0;
 711         for(i = 0; i < NHASH; i++)
 712                 for(s = hash[i]; s != S; s = s->link)
 713                         if(s->sig != 0 && s->type != SXREF && s->type != SUNDEF && (nexports == 0 || s->subtype == SEXPORT))
 714                                 esyms[n++] = s;
 715         for(i = 0; i < ne-1; i++)
 716                 for(j = i+1; j < ne; j++)
 717                         if(strcmp(esyms[i]->name, esyms[j]->name) > 0){
 718                                 s = esyms[i];
 719                                 esyms[i] = esyms[j];
 720                                 esyms[j] = s;
 721                         }
 722
 723         nb = 0;
 724         off = 0;
 725         et = lookup(EXPTAB, 0);
 726         if(et->type != 0 && et->type != SXREF)
 727                 diag("%s already defined", EXPTAB);
 728         et->type = SDATA;
 729         str = lookup(".string", 0);
 730         if(str->type == 0)
 731                 str->type = SDATA;
 732         sv = str->value;
 733         for(i = 0; i < ne; i++){
 734                 s = esyms[i];
 735                 if(debug['S'])
 736                         s->sig = 0;
 737                 /* Bprint(&bso, "EXPORT: %s sig=%lux t=%d\n", s->name, s->sig, s->type); */
 738
 739                 /* signature */
 740                 p = newdata(et, off, sizeof(long), D_EXTERN);
 741                 off += sizeof(long);
 742                 p->to.offset = s->sig;
 743
 744                 /* address */
 745                 p = newdata(et, off, sizeof(long), D_EXTERN);
 746                 off += sizeof(long);
 747                 p->to.type = D_ADDR;
 748                 p->to.index = D_EXTERN;
 749                 p->to.sym = s;
 750
 751                 /* string */
 752                 t = s->name;
 753                 n = strlen(t)+1;
 754                 for(;;){
 755                         buf[nb++] = *t;
 756                         sv++;
 757                         if(nb >= NSNAME){
 758                                 p = newdata(str, sv-NSNAME, NSNAME, D_STATIC);
 759                                 p->to.type = D_SCONST;
 760                                 memmove(p->to.scon, buf, NSNAME);
 761                                 nb = 0;
 762                         }
 763                         if(*t++ == 0)
 764                                 break;
 765                 }
 766
 767                 /* name */
 768                 p = newdata(et, off, sizeof(long), D_EXTERN);
 769                 off += sizeof(long);
 770                 p->to.type = D_ADDR;
 771                 p->to.index = D_STATIC;
 772                 p->to.sym = str;
 773                 p->to.offset = sv-n;
 774         }
 775
 776         if(nb > 0){
 777                 p = newdata(str, sv-nb, nb, D_STATIC);
 778                 p->to.type = D_SCONST;
 779                 memmove(p->to.scon, buf, nb);
 780         }
 781
 782         for(i = 0; i < 3; i++){
 783                 newdata(et, off, sizeof(long), D_EXTERN);
 784                 off += sizeof(long);
 785         }
 786         et->value = off;
 787         if(sv == 0)
 788                 sv = 1;
 789         str->value = sv;
 790         exports = ne;
 791         free(esyms);
 792 }