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