src/runtime/purify.c

   1 /*
   2  * C-level stuff to implement Lisp-level PURIFY
   3  */
   4
   5 /*
   6  * This software is part of the SBCL system. See the README file for
   7  * more information.
   8  *
   9  * This software is derived from the CMU CL system, which was
  10  * written at Carnegie Mellon University and released into the
  11  * public domain. The software is in the public domain and is
  12  * provided with absolutely no warranty. See the COPYING and CREDITS
  13  * files for more information.
  14  */
  15
  16 #include <stdio.h>
  17 #include <sys/types.h>
  18 #include <stdlib.h>
  19 #include <strings.h>
  20 #include <errno.h>
  21
  22 #include "sbcl.h"
  23 #include "runtime.h"
  24 #include "os.h"
  25 #include "globals.h"
  26 #include "validate.h"
  27 #include "interrupt.h"
  28 #include "purify.h"
  29 #include "interr.h"
  30 #include "fixnump.h"
  31 #include "gc.h"
  32 #include "gc-internal.h"
  33 #include "thread.h"
  34 #include "genesis/primitive-objects.h"
  35 #include "genesis/static-symbols.h"
  36 #include "genesis/layout.h"
  37
  38 /* We don't ever do purification with GENCGC as of 1.0.5.*. There was
  39  * a lot of hairy and fragile ifdeffage in here to support purify on
  40  * x86oids, which has now been removed. So this code can't even be
  41  * compiled with GENCGC any more.  -- JES, 2007-04-30.
  42  */
  43 #ifndef LISP_FEATURE_GENCGC
  44
  45 #define PRINTNOISE
  46
  47 static lispobj *dynamic_space_purify_pointer;
  48
  49 \f
  50 /* These hold the original end of the read_only and static spaces so
  51  * we can tell what are forwarding pointers. */
  52
  53 static lispobj *read_only_end, *static_end;
  54
  55 static lispobj *read_only_free, *static_free;
  56
  57 static lispobj *pscav(lispobj *addr, long nwords, boolean constant);
  58
  59 #define LATERBLOCKSIZE 1020
  60 #define LATERMAXCOUNT 10
  61
  62 static struct
  63 later {
  64     struct later *next;
  65     union {
  66         lispobj *ptr;
  67         long count;
  68     } u[LATERBLOCKSIZE];
  69 } *later_blocks = NULL;
  70 static long later_count = 0;
  71
  72 #if N_WORD_BITS == 32
  73  #define SIMPLE_ARRAY_WORD_WIDETAG SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG
  74 #elif N_WORD_BITS == 64
  75  #define SIMPLE_ARRAY_WORD_WIDETAG SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG
  76 #endif
  77
  78 \f
  79 static boolean
  80 forwarding_pointer_p(lispobj obj)
  81 {
  82     lispobj *ptr = native_pointer(obj);
  83
  84     return ((static_end <= ptr && ptr <= static_free) ||
  85             (read_only_end <= ptr && ptr <= read_only_free));
  86 }
  87
  88 static boolean
  89 dynamic_pointer_p(lispobj ptr)
  90 {
  91     return (ptr >= (lispobj)current_dynamic_space
  92             &&
  93             ptr < (lispobj)dynamic_space_purify_pointer);
  94 }
  95
  96 static inline lispobj *
  97 newspace_alloc(long nwords, int constantp)
  98 {
  99     lispobj *ret;
 100     nwords=CEILING(nwords,2);
 101     if(constantp) {
 102         if(read_only_free + nwords >= (lispobj *)READ_ONLY_SPACE_END) {
 103             lose("Ran out of read-only space while purifying!\n");
 104         }
 105         ret=read_only_free;
 106         read_only_free+=nwords;
 107     } else {
 108         if(static_free + nwords >= (lispobj *)STATIC_SPACE_END) {
 109             lose("Ran out of static space while purifying!\n");
 110         }
 111         ret=static_free;
 112         static_free+=nwords;
 113     }
 114     return ret;
 115 }
 116
 117 \f
 118 static void
 119 pscav_later(lispobj *where, long count)
 120 {
 121     struct later *new;
 122
 123     if (count > LATERMAXCOUNT) {
 124         while (count > LATERMAXCOUNT) {
 125             pscav_later(where, LATERMAXCOUNT);
 126             count -= LATERMAXCOUNT;
 127             where += LATERMAXCOUNT;
 128         }
 129     }
 130     else {
 131         if (later_blocks == NULL || later_count == LATERBLOCKSIZE ||
 132             (later_count == LATERBLOCKSIZE-1 && count > 1)) {
 133             new  = (struct later *)malloc(sizeof(struct later));
 134             new->next = later_blocks;
 135             if (later_blocks && later_count < LATERBLOCKSIZE)
 136                 later_blocks->u[later_count].ptr = NULL;
 137             later_blocks = new;
 138             later_count = 0;
 139         }
 140
 141         if (count != 1)
 142             later_blocks->u[later_count++].count = count;
 143         later_blocks->u[later_count++].ptr = where;
 144     }
 145 }
 146
 147 static lispobj
 148 ptrans_boxed(lispobj thing, lispobj header, boolean constant)
 149 {
 150     long nwords;
 151     lispobj result, *new, *old;
 152
 153     nwords = CEILING(1 + HeaderValue(header), 2);
 154
 155     /* Allocate it */
 156     old = (lispobj *)native_pointer(thing);
 157     new = newspace_alloc(nwords,constant);
 158
 159     /* Copy it. */
 160     bcopy(old, new, nwords * sizeof(lispobj));
 161
 162     /* Deposit forwarding pointer. */
 163     result = make_lispobj(new, lowtag_of(thing));
 164     *old = result;
 165
 166     /* Scavenge it. */
 167     pscav(new, nwords, constant);
 168
 169     return result;
 170 }
 171
 172 /* We need to look at the layout to see whether it is a pure structure
 173  * class, and only then can we transport as constant. If it is pure,
 174  * we can ALWAYS transport as a constant. */
 175 static lispobj
 176 ptrans_instance(lispobj thing, lispobj header, boolean /* ignored */ constant)
 177 {
 178     struct layout *layout =
 179       (struct layout *) native_pointer(((struct instance *)native_pointer(thing))->slots[0]);
 180     lispobj pure = layout->pure;
 181
 182     switch (pure) {
 183     case T:
 184         return (ptrans_boxed(thing, header, 1));
 185     case NIL:
 186         return (ptrans_boxed(thing, header, 0));
 187     case 0:
 188         {
 189             /* Substructure: special case for the COMPACT-INFO-ENVs,
 190              * where the instance may have a point to the dynamic
 191              * space placed into it (e.g. the cache-name slot), but
 192              * the lists and arrays at the time of a purify can be
 193              * moved to the RO space. */
 194             long nwords;
 195             lispobj result, *new, *old;
 196
 197             nwords = CEILING(1 + HeaderValue(header), 2);
 198
 199             /* Allocate it */
 200             old = (lispobj *)native_pointer(thing);
 201             new = newspace_alloc(nwords, 0); /*  inconstant */
 202
 203             /* Copy it. */
 204             bcopy(old, new, nwords * sizeof(lispobj));
 205
 206             /* Deposit forwarding pointer. */
 207             result = make_lispobj(new, lowtag_of(thing));
 208             *old = result;
 209
 210             /* Scavenge it. */
 211             pscav(new, nwords, 1);
 212
 213             return result;
 214         }
 215     default:
 216         gc_abort();
 217         return NIL; /* dummy value: return something ... */
 218     }
 219 }
 220
 221 static lispobj
 222 ptrans_fdefn(lispobj thing, lispobj header)
 223 {
 224     long nwords;
 225     lispobj result, *new, *old, oldfn;
 226     struct fdefn *fdefn;
 227
 228     nwords = CEILING(1 + HeaderValue(header), 2);
 229
 230     /* Allocate it */
 231     old = (lispobj *)native_pointer(thing);
 232     new = newspace_alloc(nwords, 0);    /* inconstant */
 233
 234     /* Copy it. */
 235     bcopy(old, new, nwords * sizeof(lispobj));
 236
 237     /* Deposit forwarding pointer. */
 238     result = make_lispobj(new, lowtag_of(thing));
 239     *old = result;
 240
 241     /* Scavenge the function. */
 242     fdefn = (struct fdefn *)new;
 243     oldfn = fdefn->fun;
 244     pscav(&fdefn->fun, 1, 0);
 245     if ((char *)oldfn + FUN_RAW_ADDR_OFFSET == fdefn->raw_addr)
 246         fdefn->raw_addr = (char *)fdefn->fun + FUN_RAW_ADDR_OFFSET;
 247
 248     return result;
 249 }
 250
 251 static lispobj
 252 ptrans_unboxed(lispobj thing, lispobj header)
 253 {
 254     long nwords;
 255     lispobj result, *new, *old;
 256
 257     nwords = CEILING(1 + HeaderValue(header), 2);
 258
 259     /* Allocate it */
 260     old = (lispobj *)native_pointer(thing);
 261     new = newspace_alloc(nwords,1);     /* always constant */
 262
 263     /* copy it. */
 264     bcopy(old, new, nwords * sizeof(lispobj));
 265
 266     /* Deposit forwarding pointer. */
 267     result = make_lispobj(new , lowtag_of(thing));
 268     *old = result;
 269
 270     return result;
 271 }
 272
 273 static lispobj
 274 ptrans_vector(lispobj thing, long bits, long extra,
 275               boolean boxed, boolean constant)
 276 {
 277     struct vector *vector;
 278     long nwords;
 279     lispobj result, *new;
 280     long length;
 281
 282     vector = (struct vector *)native_pointer(thing);
 283     length = fixnum_value(vector->length)+extra;
 284     // Argh, handle simple-vector-nil separately.
 285     if (bits == 0) {
 286       nwords = 2;
 287     } else {
 288       nwords = CEILING(NWORDS(length, bits) + 2, 2);
 289     }
 290
 291     new=newspace_alloc(nwords, (constant || !boxed));
 292     bcopy(vector, new, nwords * sizeof(lispobj));
 293
 294     result = make_lispobj(new, lowtag_of(thing));
 295     vector->header = result;
 296
 297     if (boxed)
 298         pscav(new, nwords, constant);
 299
 300     return result;
 301 }
 302
 303 static lispobj
 304 ptrans_code(lispobj thing)
 305 {
 306     struct code *code, *new;
 307     long nwords;
 308     lispobj func, result;
 309
 310     code = (struct code *)native_pointer(thing);
 311     nwords = CEILING(HeaderValue(code->header) + fixnum_value(code->code_size),
 312                      2);
 313
 314     new = (struct code *)newspace_alloc(nwords,1); /* constant */
 315
 316     bcopy(code, new, nwords * sizeof(lispobj));
 317
 318     result = make_lispobj(new, OTHER_POINTER_LOWTAG);
 319
 320     /* Stick in a forwarding pointer for the code object. */
 321     *(lispobj *)code = result;
 322
 323     /* Put in forwarding pointers for all the functions. */
 324     for (func = code->entry_points;
 325          func != NIL;
 326          func = ((struct simple_fun *)native_pointer(func))->next) {
 327
 328         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
 329
 330         *(lispobj *)native_pointer(func) = result + (func - thing);
 331     }
 332
 333     /* Arrange to scavenge the debug info later. */
 334     pscav_later(&new->debug_info, 1);
 335
 336     /* FIXME: why would this be a fixnum? */
 337     /* "why" is a hard word, but apparently for compiled functions the
 338        trace_table_offset contains the length of the instructions, as
 339        a fixnum.  See CODE-INST-AREA-LENGTH in
 340        src/compiler/target-disassem.lisp.  -- CSR, 2004-01-08 */
 341     if (!(fixnump(new->trace_table_offset)))
 342 #if 0
 343         pscav(&new->trace_table_offset, 1, 0);
 344 #else
 345         new->trace_table_offset = NIL; /* limit lifetime */
 346 #endif
 347
 348     /* Scavenge the constants. */
 349     pscav(new->constants, HeaderValue(new->header)-5, 1);
 350
 351     /* Scavenge all the functions. */
 352     pscav(&new->entry_points, 1, 1);
 353     for (func = new->entry_points;
 354          func != NIL;
 355          func = ((struct simple_fun *)native_pointer(func))->next) {
 356         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
 357         gc_assert(!dynamic_pointer_p(func));
 358
 359         pscav(&((struct simple_fun *)native_pointer(func))->self, 2, 1);
 360         pscav_later(&((struct simple_fun *)native_pointer(func))->name, 4);
 361     }
 362
 363     return result;
 364 }
 365
 366 static lispobj
 367 ptrans_func(lispobj thing, lispobj header)
 368 {
 369     long nwords;
 370     lispobj code, *new, *old, result;
 371     struct simple_fun *function;
 372
 373     /* Thing can either be a function header, a closure function
 374      * header, a closure, or a funcallable-instance. If it's a closure
 375      * or a funcallable-instance, we do the same as ptrans_boxed.
 376      * Otherwise we have to do something strange, 'cause it is buried
 377      * inside a code object. */
 378
 379     if (widetag_of(header) == SIMPLE_FUN_HEADER_WIDETAG) {
 380
 381         /* We can only end up here if the code object has not been
 382          * scavenged, because if it had been scavenged, forwarding pointers
 383          * would have been left behind for all the entry points. */
 384
 385         function = (struct simple_fun *)native_pointer(thing);
 386         code =
 387             make_lispobj
 388             ((native_pointer(thing) -
 389               (HeaderValue(function->header))), OTHER_POINTER_LOWTAG);
 390
 391         /* This will cause the function's header to be replaced with a
 392          * forwarding pointer. */
 393
 394         ptrans_code(code);
 395
 396         /* So we can just return that. */
 397         return function->header;
 398     }
 399     else {
 400         /* It's some kind of closure-like thing. */
 401         nwords = CEILING(1 + HeaderValue(header), 2);
 402         old = (lispobj *)native_pointer(thing);
 403
 404         /* Allocate the new one.  FINs *must* not go in read_only
 405          * space.  Closures can; they never change */
 406
 407         new = newspace_alloc
 408             (nwords,(widetag_of(header)!=FUNCALLABLE_INSTANCE_HEADER_WIDETAG));
 409
 410         /* Copy it. */
 411         bcopy(old, new, nwords * sizeof(lispobj));
 412
 413         /* Deposit forwarding pointer. */
 414         result = make_lispobj(new, lowtag_of(thing));
 415         *old = result;
 416
 417         /* Scavenge it. */
 418         pscav(new, nwords, 0);
 419
 420         return result;
 421     }
 422 }
 423
 424 static lispobj
 425 ptrans_returnpc(lispobj thing, lispobj header)
 426 {
 427     lispobj code, new;
 428
 429     /* Find the corresponding code object. */
 430     code = thing - HeaderValue(header)*sizeof(lispobj);
 431
 432     /* Make sure it's been transported. */
 433     new = *(lispobj *)native_pointer(code);
 434     if (!forwarding_pointer_p(new))
 435         new = ptrans_code(code);
 436
 437     /* Maintain the offset: */
 438     return new + (thing - code);
 439 }
 440
 441 #define WORDS_PER_CONS CEILING(sizeof(struct cons) / sizeof(lispobj), 2)
 442
 443 static lispobj
 444 ptrans_list(lispobj thing, boolean constant)
 445 {
 446     struct cons *old, *new, *orig;
 447     long length;
 448
 449     orig = (struct cons *) newspace_alloc(0,constant);
 450     length = 0;
 451
 452     do {
 453         /* Allocate a new cons cell. */
 454         old = (struct cons *)native_pointer(thing);
 455         new = (struct cons *) newspace_alloc(WORDS_PER_CONS,constant);
 456
 457         /* Copy the cons cell and keep a pointer to the cdr. */
 458         new->car = old->car;
 459         thing = new->cdr = old->cdr;
 460
 461         /* Set up the forwarding pointer. */
 462         *(lispobj *)old = make_lispobj(new, LIST_POINTER_LOWTAG);
 463
 464         /* And count this cell. */
 465         length++;
 466     } while (lowtag_of(thing) == LIST_POINTER_LOWTAG &&
 467              dynamic_pointer_p(thing) &&
 468              !(forwarding_pointer_p(*(lispobj *)native_pointer(thing))));
 469
 470     /* Scavenge the list we just copied. */
 471     pscav((lispobj *)orig, length * WORDS_PER_CONS, constant);
 472
 473     return make_lispobj(orig, LIST_POINTER_LOWTAG);
 474 }
 475
 476 static lispobj
 477 ptrans_otherptr(lispobj thing, lispobj header, boolean constant)
 478 {
 479     switch (widetag_of(header)) {
 480         /* FIXME: this needs a reindent */
 481       case BIGNUM_WIDETAG:
 482       case SINGLE_FLOAT_WIDETAG:
 483       case DOUBLE_FLOAT_WIDETAG:
 484 #ifdef LONG_FLOAT_WIDETAG
 485       case LONG_FLOAT_WIDETAG:
 486 #endif
 487 #ifdef COMPLEX_SINGLE_FLOAT_WIDETAG
 488       case COMPLEX_SINGLE_FLOAT_WIDETAG:
 489 #endif
 490 #ifdef COMPLEX_DOUBLE_FLOAT_WIDETAG
 491       case COMPLEX_DOUBLE_FLOAT_WIDETAG:
 492 #endif
 493 #ifdef COMPLEX_LONG_FLOAT_WIDETAG
 494       case COMPLEX_LONG_FLOAT_WIDETAG:
 495 #endif
 496       case SAP_WIDETAG:
 497           return ptrans_unboxed(thing, header);
 498 #ifdef LUTEX_WIDETAG
 499       case LUTEX_WIDETAG:
 500           gencgc_unregister_lutex(native_pointer(thing));
 501           return ptrans_unboxed(thing, header);
 502 #endif
 503
 504       case RATIO_WIDETAG:
 505       case COMPLEX_WIDETAG:
 506       case SIMPLE_ARRAY_WIDETAG:
 507       case COMPLEX_BASE_STRING_WIDETAG:
 508 #ifdef COMPLEX_CHARACTER_STRING_WIDETAG
 509     case COMPLEX_CHARACTER_STRING_WIDETAG:
 510 #endif
 511       case COMPLEX_BIT_VECTOR_WIDETAG:
 512       case COMPLEX_VECTOR_NIL_WIDETAG:
 513       case COMPLEX_VECTOR_WIDETAG:
 514       case COMPLEX_ARRAY_WIDETAG:
 515         return ptrans_boxed(thing, header, constant);
 516
 517       case VALUE_CELL_HEADER_WIDETAG:
 518       case WEAK_POINTER_WIDETAG:
 519         return ptrans_boxed(thing, header, 0);
 520
 521       case SYMBOL_HEADER_WIDETAG:
 522         return ptrans_boxed(thing, header, 0);
 523
 524       case SIMPLE_ARRAY_NIL_WIDETAG:
 525         return ptrans_vector(thing, 0, 0, 0, constant);
 526
 527       case SIMPLE_BASE_STRING_WIDETAG:
 528         return ptrans_vector(thing, 8, 1, 0, constant);
 529
 530 #ifdef SIMPLE_CHARACTER_STRING_WIDETAG
 531     case SIMPLE_CHARACTER_STRING_WIDETAG:
 532         return ptrans_vector(thing, 32, 1, 0, constant);
 533 #endif
 534
 535       case SIMPLE_BIT_VECTOR_WIDETAG:
 536         return ptrans_vector(thing, 1, 0, 0, constant);
 537
 538       case SIMPLE_VECTOR_WIDETAG:
 539         return ptrans_vector(thing, N_WORD_BITS, 0, 1, constant);
 540
 541       case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
 542         return ptrans_vector(thing, 2, 0, 0, constant);
 543
 544       case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
 545         return ptrans_vector(thing, 4, 0, 0, constant);
 546
 547       case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
 548 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
 549       case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
 550       case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
 551 #endif
 552         return ptrans_vector(thing, 8, 0, 0, constant);
 553
 554       case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
 555 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
 556       case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
 557       case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
 558 #endif
 559         return ptrans_vector(thing, 16, 0, 0, constant);
 560
 561       case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
 562 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
 563       case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
 564       case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
 565 #endif
 566 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
 567       case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
 568       case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
 569 #endif
 570         return ptrans_vector(thing, 32, 0, 0, constant);
 571
 572 #if N_WORD_BITS == 64
 573 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_60_WIDETAG
 574       case SIMPLE_ARRAY_UNSIGNED_BYTE_60_WIDETAG:
 575 #endif
 576 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_63_WIDETAG
 577       case SIMPLE_ARRAY_UNSIGNED_BYTE_63_WIDETAG:
 578 #endif
 579 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG
 580       case SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG:
 581 #endif
 582 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG
 583       case SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG:
 584 #endif
 585 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG
 586       case SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG:
 587 #endif
 588         return ptrans_vector(thing, 64, 0, 0, constant);
 589 #endif
 590
 591       case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
 592         return ptrans_vector(thing, 32, 0, 0, constant);
 593
 594       case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
 595         return ptrans_vector(thing, 64, 0, 0, constant);
 596
 597 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
 598       case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
 599 #ifdef LISP_FEATURE_SPARC
 600         return ptrans_vector(thing, 128, 0, 0, constant);
 601 #endif
 602 #endif
 603
 604 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
 605       case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
 606         return ptrans_vector(thing, 64, 0, 0, constant);
 607 #endif
 608
 609 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
 610       case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
 611         return ptrans_vector(thing, 128, 0, 0, constant);
 612 #endif
 613
 614 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
 615       case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
 616 #ifdef LISP_FEATURE_SPARC
 617         return ptrans_vector(thing, 256, 0, 0, constant);
 618 #endif
 619 #endif
 620
 621       case CODE_HEADER_WIDETAG:
 622         return ptrans_code(thing);
 623
 624       case RETURN_PC_HEADER_WIDETAG:
 625         return ptrans_returnpc(thing, header);
 626
 627       case FDEFN_WIDETAG:
 628         return ptrans_fdefn(thing, header);
 629
 630       default:
 631         fprintf(stderr, "Invalid widetag: %d\n", widetag_of(header));
 632         /* Should only come across other pointers to the above stuff. */
 633         gc_abort();
 634         return NIL;
 635     }
 636 }
 637
 638 static long
 639 pscav_fdefn(struct fdefn *fdefn)
 640 {
 641     boolean fix_func;
 642
 643     fix_func = ((char *)(fdefn->fun+FUN_RAW_ADDR_OFFSET) == fdefn->raw_addr);
 644     pscav(&fdefn->name, 1, 1);
 645     pscav(&fdefn->fun, 1, 0);
 646     if (fix_func)
 647         fdefn->raw_addr = (char *)(fdefn->fun + FUN_RAW_ADDR_OFFSET);
 648     return sizeof(struct fdefn) / sizeof(lispobj);
 649 }
 650
 651 static lispobj *
 652 pscav(lispobj *addr, long nwords, boolean constant)
 653 {
 654     lispobj thing, *thingp, header;
 655     long count = 0; /* (0 = dummy init value to stop GCC warning) */
 656     struct vector *vector;
 657
 658     while (nwords > 0) {
 659         thing = *addr;
 660         if (is_lisp_pointer(thing)) {
 661             /* It's a pointer. Is it something we might have to move? */
 662             if (dynamic_pointer_p(thing)) {
 663                 /* Maybe. Have we already moved it? */
 664                 thingp = (lispobj *)native_pointer(thing);
 665                 header = *thingp;
 666                 if (is_lisp_pointer(header) && forwarding_pointer_p(header))
 667                     /* Yep, so just copy the forwarding pointer. */
 668                     thing = header;
 669                 else {
 670                     /* Nope, copy the object. */
 671                     switch (lowtag_of(thing)) {
 672                       case FUN_POINTER_LOWTAG:
 673                         thing = ptrans_func(thing, header);
 674                         break;
 675
 676                       case LIST_POINTER_LOWTAG:
 677                         thing = ptrans_list(thing, constant);
 678                         break;
 679
 680                       case INSTANCE_POINTER_LOWTAG:
 681                         thing = ptrans_instance(thing, header, constant);
 682                         break;
 683
 684                       case OTHER_POINTER_LOWTAG:
 685                         thing = ptrans_otherptr(thing, header, constant);
 686                         break;
 687
 688                       default:
 689                         /* It was a pointer, but not one of them? */
 690                         gc_abort();
 691                     }
 692                 }
 693                 *addr = thing;
 694             }
 695             count = 1;
 696         }
 697 #if N_WORD_BITS == 64
 698         else if (widetag_of(thing) == SINGLE_FLOAT_WIDETAG) {
 699             count = 1;
 700         }
 701 #endif
 702         else if (thing & FIXNUM_TAG_MASK) {
 703             /* It's an other immediate. Maybe the header for an unboxed */
 704             /* object. */
 705             switch (widetag_of(thing)) {
 706               case BIGNUM_WIDETAG:
 707               case SINGLE_FLOAT_WIDETAG:
 708               case DOUBLE_FLOAT_WIDETAG:
 709 #ifdef LONG_FLOAT_WIDETAG
 710               case LONG_FLOAT_WIDETAG:
 711 #endif
 712               case SAP_WIDETAG:
 713                 /* It's an unboxed simple object. */
 714                 count = CEILING(HeaderValue(thing)+1, 2);
 715                 break;
 716
 717               case SIMPLE_VECTOR_WIDETAG:
 718                   if (HeaderValue(thing) == subtype_VectorValidHashing) {
 719                     *addr = (subtype_VectorMustRehash << N_WIDETAG_BITS) |
 720                         SIMPLE_VECTOR_WIDETAG;
 721                   }
 722                 count = 2;
 723                 break;
 724
 725               case SIMPLE_ARRAY_NIL_WIDETAG:
 726                 count = 2;
 727                 break;
 728
 729               case SIMPLE_BASE_STRING_WIDETAG:
 730                 vector = (struct vector *)addr;
 731                 count = CEILING(NWORDS(fixnum_value(vector->length)+1,8)+2,2);
 732                 break;
 733
 734 #ifdef SIMPLE_CHARACTER_STRING_WIDETAG
 735             case SIMPLE_CHARACTER_STRING_WIDETAG:
 736                 vector = (struct vector *)addr;
 737                 count = CEILING(NWORDS(fixnum_value(vector->length)+1,32)+2,2);
 738                 break;
 739 #endif
 740
 741               case SIMPLE_BIT_VECTOR_WIDETAG:
 742                 vector = (struct vector *)addr;
 743                 count = CEILING(NWORDS(fixnum_value(vector->length),1)+2,2);
 744                 break;
 745
 746               case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
 747                 vector = (struct vector *)addr;
 748                 count = CEILING(NWORDS(fixnum_value(vector->length),2)+2,2);
 749                 break;
 750
 751               case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
 752                 vector = (struct vector *)addr;
 753                 count = CEILING(NWORDS(fixnum_value(vector->length),4)+2,2);
 754                 break;
 755
 756               case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
 757 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
 758               case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
 759               case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
 760 #endif
 761                 vector = (struct vector *)addr;
 762                 count = CEILING(NWORDS(fixnum_value(vector->length),8)+2,2);
 763                 break;
 764
 765               case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
 766 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
 767               case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
 768               case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
 769 #endif
 770                 vector = (struct vector *)addr;
 771                 count = CEILING(NWORDS(fixnum_value(vector->length),16)+2,2);
 772                 break;
 773
 774               case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
 775 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
 776               case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
 777               case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
 778 #endif
 779 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
 780               case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
 781               case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
 782 #endif
 783                 vector = (struct vector *)addr;
 784                 count = CEILING(NWORDS(fixnum_value(vector->length),32)+2,2);
 785                 break;
 786
 787 #if N_WORD_BITS == 64
 788               case SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG:
 789 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG
 790               case SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG:
 791               case SIMPLE_ARRAY_UNSIGNED_BYTE_60_WIDETAG:
 792 #endif
 793 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG
 794               case SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG:
 795               case SIMPLE_ARRAY_UNSIGNED_BYTE_63_WIDETAG:
 796 #endif
 797                 vector = (struct vector *)addr;
 798                 count = CEILING(NWORDS(fixnum_value(vector->length),64)+2,2);
 799                 break;
 800 #endif
 801
 802               case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
 803                 vector = (struct vector *)addr;
 804                 count = CEILING(NWORDS(fixnum_value(vector->length), 32) + 2,
 805                                 2);
 806                 break;
 807
 808               case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
 809 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
 810               case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
 811 #endif
 812                 vector = (struct vector *)addr;
 813                 count = CEILING(NWORDS(fixnum_value(vector->length), 64) + 2,
 814                                 2);
 815                 break;
 816
 817 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
 818               case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
 819                 vector = (struct vector *)addr;
 820 #ifdef LISP_FEATURE_SPARC
 821                 count = fixnum_value(vector->length)*4+2;
 822 #endif
 823                 break;
 824 #endif
 825
 826 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
 827               case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
 828                 vector = (struct vector *)addr;
 829                 count = CEILING(NWORDS(fixnum_value(vector->length), 128) + 2,
 830                                 2);
 831                 break;
 832 #endif
 833
 834 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
 835               case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
 836                 vector = (struct vector *)addr;
 837 #ifdef LISP_FEATURE_SPARC
 838                 count = fixnum_value(vector->length)*8+2;
 839 #endif
 840                 break;
 841 #endif
 842
 843               case CODE_HEADER_WIDETAG:
 844                 gc_abort(); /* no code headers in static space */
 845                 break;
 846
 847               case SIMPLE_FUN_HEADER_WIDETAG:
 848               case RETURN_PC_HEADER_WIDETAG:
 849                 /* We should never hit any of these, 'cause they occur
 850                  * buried in the middle of code objects. */
 851                 gc_abort();
 852                 break;
 853
 854               case WEAK_POINTER_WIDETAG:
 855                 /* Weak pointers get preserved during purify, 'cause I
 856                  * don't feel like figuring out how to break them. */
 857                 pscav(addr+1, 2, constant);
 858                 count = 4;
 859                 break;
 860
 861               case FDEFN_WIDETAG:
 862                 /* We have to handle fdefn objects specially, so we
 863                  * can fix up the raw function address. */
 864                 count = pscav_fdefn((struct fdefn *)addr);
 865                 break;
 866
 867               case INSTANCE_HEADER_WIDETAG:
 868                 {
 869                     struct instance *instance = (struct instance *) addr;
 870                     struct layout *layout
 871                         = (struct layout *) native_pointer(instance->slots[0]);
 872                     long nuntagged = fixnum_value(layout->n_untagged_slots);
 873                     long nslots = HeaderValue(*addr);
 874                     pscav(addr + 1, nslots - nuntagged, constant);
 875                     count = CEILING(1 + nslots, 2);
 876                 }
 877                 break;
 878
 879               default:
 880                 count = 1;
 881                 break;
 882             }
 883         }
 884         else {
 885             /* It's a fixnum. */
 886             count = 1;
 887         }
 888
 889         addr += count;
 890         nwords -= count;
 891     }
 892
 893     return addr;
 894 }
 895
 896 int
 897 purify(lispobj static_roots, lispobj read_only_roots)
 898 {
 899     lispobj *clean;
 900     long count, i;
 901     struct later *laters, *next;
 902     struct thread *thread;
 903
 904     if(all_threads->next) {
 905         /* FIXME: there should be _some_ sensible error reporting
 906          * convention.  See following comment too */
 907         fprintf(stderr,"Can't purify when more than one thread exists\n");
 908         fflush(stderr);
 909         return 0;
 910     }
 911
 912 #ifdef PRINTNOISE
 913     printf("[doing purification:");
 914     fflush(stdout);
 915 #endif
 916
 917     for_each_thread(thread)
 918         if (fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread)) != 0) {
 919         /* FIXME: 1. What does this mean? 2. It shouldn't be reporting
 920          * its error simply by a. printing a string b. to stdout instead
 921          * of stderr. */
 922         printf(" Ack! Can't purify interrupt contexts. ");
 923         fflush(stdout);
 924         return 0;
 925     }
 926
 927     dynamic_space_purify_pointer = dynamic_space_free_pointer;
 928
 929     read_only_end = read_only_free =
 930         (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER,0);
 931     static_end = static_free =
 932         (lispobj *)SymbolValue(STATIC_SPACE_FREE_POINTER,0);
 933
 934 #ifdef PRINTNOISE
 935     printf(" roots");
 936     fflush(stdout);
 937 #endif
 938
 939     pscav(&static_roots, 1, 0);
 940     pscav(&read_only_roots, 1, 1);
 941
 942 #ifdef PRINTNOISE
 943     printf(" handlers");
 944     fflush(stdout);
 945 #endif
 946     pscav((lispobj *) interrupt_handlers,
 947           sizeof(interrupt_handlers) / sizeof(lispobj),
 948           0);
 949
 950 #ifdef PRINTNOISE
 951     printf(" stack");
 952     fflush(stdout);
 953 #endif
 954     pscav((lispobj *)all_threads->control_stack_start,
 955           current_control_stack_pointer -
 956           all_threads->control_stack_start,
 957           0);
 958
 959 #ifdef PRINTNOISE
 960     printf(" bindings");
 961     fflush(stdout);
 962 #endif
 963
 964     pscav( (lispobj *)all_threads->binding_stack_start,
 965           (lispobj *)current_binding_stack_pointer -
 966            all_threads->binding_stack_start,
 967           0);
 968
 969     /* The original CMU CL code had scavenge-read-only-space code
 970      * controlled by the Lisp-level variable
 971      * *SCAVENGE-READ-ONLY-SPACE*. It was disabled by default, and it
 972      * wasn't documented under what circumstances it was useful or
 973      * safe to turn it on, so it's been turned off in SBCL. If you
 974      * want/need this functionality, and can test and document it,
 975      * please submit a patch. */
 976 #if 0
 977     if (SymbolValue(SCAVENGE_READ_ONLY_SPACE) != UNBOUND_MARKER_WIDETAG
 978         && SymbolValue(SCAVENGE_READ_ONLY_SPACE) != NIL) {
 979       unsigned  read_only_space_size =
 980           (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER) -
 981           (lispobj *)READ_ONLY_SPACE_START;
 982       fprintf(stderr,
 983               "scavenging read only space: %d bytes\n",
 984               read_only_space_size * sizeof(lispobj));
 985       pscav( (lispobj *)READ_ONLY_SPACE_START, read_only_space_size, 0);
 986     }
 987 #endif
 988
 989 #ifdef PRINTNOISE
 990     printf(" static");
 991     fflush(stdout);
 992 #endif
 993     clean = (lispobj *)STATIC_SPACE_START;
 994     do {
 995         while (clean != static_free)
 996             clean = pscav(clean, static_free - clean, 0);
 997         laters = later_blocks;
 998         count = later_count;
 999         later_blocks = NULL;
1000         later_count = 0;
1001         while (laters != NULL) {
1002             for (i = 0; i < count; i++) {
1003                 if (laters->u[i].count == 0) {
1004                     ;
1005                 } else if (laters->u[i].count <= LATERMAXCOUNT) {
1006                     pscav(laters->u[i+1].ptr, laters->u[i].count, 1);
1007                     i++;
1008                 } else {
1009                     pscav(laters->u[i].ptr, 1, 1);
1010                 }
1011             }
1012             next = laters->next;
1013             free(laters);
1014             laters = next;
1015             count = LATERBLOCKSIZE;
1016         }
1017     } while (clean != static_free || later_blocks != NULL);
1018
1019 #ifdef PRINTNOISE
1020     printf(" cleanup");
1021     fflush(stdout);
1022 #endif
1023
1024     os_zero((os_vm_address_t) current_dynamic_space,
1025             (os_vm_size_t) dynamic_space_size);
1026
1027     /* Zero the stack. */
1028     os_zero((os_vm_address_t) current_control_stack_pointer,
1029             (os_vm_size_t)
1030             ((all_threads->control_stack_end -
1031               current_control_stack_pointer) * sizeof(lispobj)));
1032
1033     /* It helps to update the heap free pointers so that free_heap can
1034      * verify after it's done. */
1035     SetSymbolValue(READ_ONLY_SPACE_FREE_POINTER, (lispobj)read_only_free,0);
1036     SetSymbolValue(STATIC_SPACE_FREE_POINTER, (lispobj)static_free,0);
1037
1038     dynamic_space_free_pointer = current_dynamic_space;
1039     set_auto_gc_trigger(bytes_consed_between_gcs);
1040
1041     /* Blast away instruction cache */
1042     os_flush_icache((os_vm_address_t)READ_ONLY_SPACE_START, READ_ONLY_SPACE_SIZE);
1043     os_flush_icache((os_vm_address_t)STATIC_SPACE_START, STATIC_SPACE_SIZE);
1044
1045 #ifdef PRINTNOISE
1046     printf(" done]\n");
1047     fflush(stdout);
1048 #endif
1049     return 0;
1050 }
1051 #else /* LISP_FEATURE_GENCGC */
1052 int
1053 purify(lispobj static_roots, lispobj read_only_roots)
1054 {
1055     lose("purify called for GENCGC. This should not happen.");
1056 }
1057 #endif /* LISP_FEATURE_GENCGC */