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 "gc.h"
  31 #include "gc-internal.h"
  32 #include "thread.h"
  33 #include "genesis/primitive-objects.h"
  34 #include "genesis/static-symbols.h"
  35
  36 #define PRINTNOISE
  37
  38 #if defined(LISP_FEATURE_GENCGC)
  39 /* this is another artifact of the poor integration between gencgc and
  40  * the rest of the runtime: on cheney gc there is a global
  41  * dynamic_space_free_pointer which is valid whenever foreign function
  42  * call is active, but in gencgc there's no such variable and we have
  43  * to keep our own
  44  */
  45 static lispobj *dynamic_space_free_pointer;
  46 #endif
  47 extern unsigned long bytes_consed_between_gcs;
  48
  49 #define gc_abort() \
  50   lose("GC invariant lost, file \"%s\", line %d", __FILE__, __LINE__)
  51
  52 #if 1
  53 #define gc_assert(ex) do { \
  54         if (!(ex)) gc_abort(); \
  55 } while (0)
  56 #else
  57 #define gc_assert(ex)
  58 #endif
  59
  60 \f
  61 /* These hold the original end of the read_only and static spaces so
  62  * we can tell what are forwarding pointers. */
  63
  64 static lispobj *read_only_end, *static_end;
  65
  66 static lispobj *read_only_free, *static_free;
  67
  68 static lispobj *pscav(lispobj *addr, int nwords, boolean constant);
  69
  70 #define LATERBLOCKSIZE 1020
  71 #define LATERMAXCOUNT 10
  72
  73 static struct
  74 later {
  75     struct later *next;
  76     union {
  77         lispobj *ptr;
  78         int count;
  79     } u[LATERBLOCKSIZE];
  80 } *later_blocks = NULL;
  81 static int later_count = 0;
  82
  83 #define CEILING(x,y) (((x) + ((y) - 1)) & (~((y) - 1)))
  84 #define NWORDS(x,y) (CEILING((x),(y)) / (y))
  85
  86 /* FIXME: Shouldn't this be defined in sbcl.h?  See also notes in
  87  * cheneygc.c */
  88
  89 #ifdef sparc
  90 #define FUN_RAW_ADDR_OFFSET 0
  91 #else
  92 #define FUN_RAW_ADDR_OFFSET (6*sizeof(lispobj) - FUN_POINTER_LOWTAG)
  93 #endif
  94 \f
  95 static boolean
  96 forwarding_pointer_p(lispobj obj)
  97 {
  98     lispobj *ptr = native_pointer(obj);
  99
 100     return ((static_end <= ptr && ptr <= static_free) ||
 101             (read_only_end <= ptr && ptr <= read_only_free));
 102 }
 103
 104 static boolean
 105 dynamic_pointer_p(lispobj ptr)
 106 {
 107 #ifndef LISP_FEATURE_GENCGC
 108     return (ptr >= (lispobj)current_dynamic_space
 109             &&
 110             ptr < (lispobj)dynamic_space_free_pointer);
 111 #else
 112     /* Be more conservative, and remember, this is a maybe. */
 113     return (ptr >= (lispobj)DYNAMIC_SPACE_START
 114             &&
 115             ptr < (lispobj)dynamic_space_free_pointer);
 116 #endif
 117 }
 118
 119 static inline lispobj *
 120 newspace_alloc(int nwords, int constantp)
 121 {
 122     lispobj *ret;
 123     nwords=CEILING(nwords,2);
 124     if(constantp) {
 125         ret=read_only_free;
 126         read_only_free+=nwords;
 127     } else {
 128         ret=static_free;
 129         static_free+=nwords;
 130     }
 131     return ret;
 132 }
 133
 134
 135 \f
 136 #ifdef LISP_FEATURE_X86
 137
 138 #ifdef LISP_FEATURE_GENCGC
 139 /*
 140  * enhanced x86/GENCGC stack scavenging by Douglas Crosher
 141  *
 142  * Scavenging the stack on the i386 is problematic due to conservative
 143  * roots and raw return addresses. Here it is handled in two passes:
 144  * the first pass runs before any objects are moved and tries to
 145  * identify valid pointers and return address on the stack, the second
 146  * pass scavenges these.
 147  */
 148
 149 static unsigned pointer_filter_verbose = 0;
 150
 151 /* FIXME: This is substantially the same code as
 152  * possibly_valid_dynamic_space_pointer in gencgc.c.  The only
 153  * relevant difference seems to be that the gencgc code also checks
 154  * for raw pointers into Code objects, whereas in purify these are
 155  * checked separately in setup_i386_stack_scav - they go onto
 156  * valid_stack_ra_locations instead of just valid_stack_locations */
 157
 158 static int
 159 valid_dynamic_space_pointer(lispobj *pointer, lispobj *start_addr)
 160 {
 161     /* If it's not a return address then it needs to be a valid Lisp
 162      * pointer. */
 163     if (!is_lisp_pointer((lispobj)pointer))
 164         return 0;
 165
 166     /* Check that the object pointed to is consistent with the pointer
 167      * low tag. */
 168     switch (lowtag_of((lispobj)pointer)) {
 169     case FUN_POINTER_LOWTAG:
 170         /* Start_addr should be the enclosing code object, or a closure
 171          * header. */
 172         switch (widetag_of(*start_addr)) {
 173         case CODE_HEADER_WIDETAG:
 174             /* This case is probably caught above. */
 175             break;
 176         case CLOSURE_HEADER_WIDETAG:
 177         case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
 178             if ((int)pointer != ((int)start_addr+FUN_POINTER_LOWTAG)) {
 179                 if (pointer_filter_verbose) {
 180                     fprintf(stderr,"*Wf2: %x %x %x\n", (unsigned int) pointer,
 181                             (unsigned int) start_addr, *start_addr);
 182                 }
 183                 return 0;
 184             }
 185             break;
 186         default:
 187             if (pointer_filter_verbose) {
 188                 fprintf(stderr,"*Wf3: %x %x %x\n", (unsigned int) pointer,
 189                         (unsigned int) start_addr, *start_addr);
 190             }
 191             return 0;
 192         }
 193         break;
 194     case LIST_POINTER_LOWTAG:
 195         if ((int)pointer != ((int)start_addr+LIST_POINTER_LOWTAG)) {
 196             if (pointer_filter_verbose)
 197                 fprintf(stderr,"*Wl1: %x %x %x\n", (unsigned int) pointer,
 198                         (unsigned int) start_addr, *start_addr);
 199             return 0;
 200         }
 201         /* Is it plausible cons? */
 202         if ((is_lisp_pointer(start_addr[0])
 203             || ((start_addr[0] & 3) == 0) /* fixnum */
 204             || (widetag_of(start_addr[0]) == BASE_CHAR_WIDETAG)
 205             || (widetag_of(start_addr[0]) == UNBOUND_MARKER_WIDETAG))
 206            && (is_lisp_pointer(start_addr[1])
 207                || ((start_addr[1] & 3) == 0) /* fixnum */
 208                || (widetag_of(start_addr[1]) == BASE_CHAR_WIDETAG)
 209                || (widetag_of(start_addr[1]) == UNBOUND_MARKER_WIDETAG))) {
 210             break;
 211         } else {
 212             if (pointer_filter_verbose) {
 213                 fprintf(stderr,"*Wl2: %x %x %x\n", (unsigned int) pointer,
 214                         (unsigned int) start_addr, *start_addr);
 215             }
 216             return 0;
 217         }
 218     case INSTANCE_POINTER_LOWTAG:
 219         if ((int)pointer != ((int)start_addr+INSTANCE_POINTER_LOWTAG)) {
 220             if (pointer_filter_verbose) {
 221                 fprintf(stderr,"*Wi1: %x %x %x\n", (unsigned int) pointer,
 222                         (unsigned int) start_addr, *start_addr);
 223             }
 224             return 0;
 225         }
 226         if (widetag_of(start_addr[0]) != INSTANCE_HEADER_WIDETAG) {
 227             if (pointer_filter_verbose) {
 228                 fprintf(stderr,"*Wi2: %x %x %x\n", (unsigned int) pointer,
 229                         (unsigned int) start_addr, *start_addr);
 230             }
 231             return 0;
 232         }
 233         break;
 234     case OTHER_POINTER_LOWTAG:
 235         if ((int)pointer != ((int)start_addr+OTHER_POINTER_LOWTAG)) {
 236             if (pointer_filter_verbose) {
 237                 fprintf(stderr,"*Wo1: %x %x %x\n", (unsigned int) pointer,
 238                         (unsigned int) start_addr, *start_addr);
 239             }
 240             return 0;
 241         }
 242         /* Is it plausible? Not a cons. XXX should check the headers. */
 243         if (is_lisp_pointer(start_addr[0]) || ((start_addr[0] & 3) == 0)) {
 244             if (pointer_filter_verbose) {
 245                 fprintf(stderr,"*Wo2: %x %x %x\n", (unsigned int) pointer,
 246                         (unsigned int) start_addr, *start_addr);
 247             }
 248             return 0;
 249         }
 250         switch (widetag_of(start_addr[0])) {
 251         case UNBOUND_MARKER_WIDETAG:
 252         case BASE_CHAR_WIDETAG:
 253             if (pointer_filter_verbose) {
 254                 fprintf(stderr,"*Wo3: %x %x %x\n", (unsigned int) pointer,
 255                         (unsigned int) start_addr, *start_addr);
 256             }
 257             return 0;
 258
 259             /* only pointed to by function pointers? */
 260         case CLOSURE_HEADER_WIDETAG:
 261         case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
 262             if (pointer_filter_verbose) {
 263                 fprintf(stderr,"*Wo4: %x %x %x\n", (unsigned int) pointer,
 264                         (unsigned int) start_addr, *start_addr);
 265             }
 266             return 0;
 267
 268         case INSTANCE_HEADER_WIDETAG:
 269             if (pointer_filter_verbose) {
 270                 fprintf(stderr,"*Wo5: %x %x %x\n", (unsigned int) pointer,
 271                         (unsigned int) start_addr, *start_addr);
 272             }
 273             return 0;
 274
 275             /* the valid other immediate pointer objects */
 276         case SIMPLE_VECTOR_WIDETAG:
 277         case RATIO_WIDETAG:
 278         case COMPLEX_WIDETAG:
 279 #ifdef COMPLEX_SINGLE_FLOAT_WIDETAG
 280         case COMPLEX_SINGLE_FLOAT_WIDETAG:
 281 #endif
 282 #ifdef COMPLEX_DOUBLE_FLOAT_WIDETAG
 283         case COMPLEX_DOUBLE_FLOAT_WIDETAG:
 284 #endif
 285 #ifdef COMPLEX_LONG_FLOAT_WIDETAG
 286         case COMPLEX_LONG_FLOAT_WIDETAG:
 287 #endif
 288         case SIMPLE_ARRAY_WIDETAG:
 289         case COMPLEX_BASE_STRING_WIDETAG:
 290         case COMPLEX_VECTOR_NIL_WIDETAG:
 291         case COMPLEX_BIT_VECTOR_WIDETAG:
 292         case COMPLEX_VECTOR_WIDETAG:
 293         case COMPLEX_ARRAY_WIDETAG:
 294         case VALUE_CELL_HEADER_WIDETAG:
 295         case SYMBOL_HEADER_WIDETAG:
 296         case FDEFN_WIDETAG:
 297         case CODE_HEADER_WIDETAG:
 298         case BIGNUM_WIDETAG:
 299         case SINGLE_FLOAT_WIDETAG:
 300         case DOUBLE_FLOAT_WIDETAG:
 301 #ifdef LONG_FLOAT_WIDETAG
 302         case LONG_FLOAT_WIDETAG:
 303 #endif
 304         case SIMPLE_ARRAY_NIL_WIDETAG:
 305         case SIMPLE_BASE_STRING_WIDETAG:
 306         case SIMPLE_BIT_VECTOR_WIDETAG:
 307         case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
 308         case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
 309         case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
 310         case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
 311         case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
 312         case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
 313         case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
 314         case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
 315         case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
 316 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
 317         case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
 318 #endif
 319 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
 320         case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
 321 #endif
 322 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
 323         case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
 324 #endif
 325 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
 326         case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
 327 #endif
 328         case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
 329         case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
 330 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
 331         case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
 332 #endif
 333 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
 334         case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
 335 #endif
 336 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
 337         case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
 338 #endif
 339 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
 340         case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
 341 #endif
 342         case SAP_WIDETAG:
 343         case WEAK_POINTER_WIDETAG:
 344             break;
 345
 346         default:
 347             if (pointer_filter_verbose) {
 348                 fprintf(stderr,"*Wo6: %x %x %x\n", (unsigned int) pointer,
 349                         (unsigned int) start_addr, *start_addr);
 350             }
 351             return 0;
 352         }
 353         break;
 354     default:
 355         if (pointer_filter_verbose) {
 356             fprintf(stderr,"*W?: %x %x %x\n", (unsigned int) pointer,
 357                     (unsigned int) start_addr, *start_addr);
 358         }
 359         return 0;
 360     }
 361
 362     /* looks good */
 363     return 1;
 364 }
 365
 366 #define MAX_STACK_POINTERS 256
 367 lispobj *valid_stack_locations[MAX_STACK_POINTERS];
 368 unsigned int num_valid_stack_locations;
 369
 370 #define MAX_STACK_RETURN_ADDRESSES 128
 371 lispobj *valid_stack_ra_locations[MAX_STACK_RETURN_ADDRESSES];
 372 lispobj *valid_stack_ra_code_objects[MAX_STACK_RETURN_ADDRESSES];
 373 unsigned int num_valid_stack_ra_locations;
 374
 375 /* Identify valid stack slots. */
 376 static void
 377 setup_i386_stack_scav(lispobj *lowaddr, lispobj *base)
 378 {
 379     lispobj *sp = lowaddr;
 380     num_valid_stack_locations = 0;
 381     num_valid_stack_ra_locations = 0;
 382     for (sp = lowaddr; sp < base; sp++) {
 383         lispobj thing = *sp;
 384         /* Find the object start address */
 385         lispobj *start_addr = search_dynamic_space((void *)thing);
 386         if (start_addr) {
 387             /* We need to allow raw pointers into Code objects for
 388              * return addresses. This will also pick up pointers to
 389              * functions in code objects. */
 390             if (widetag_of(*start_addr) == CODE_HEADER_WIDETAG) {
 391                 /* FIXME asserting here is a really dumb thing to do.
 392                  * If we've overflowed some arbitrary static limit, we
 393                  * should just refuse to purify, instead of killing
 394                  * the whole lisp session
 395                  */
 396                 gc_assert(num_valid_stack_ra_locations <
 397                           MAX_STACK_RETURN_ADDRESSES);
 398                 valid_stack_ra_locations[num_valid_stack_ra_locations] = sp;
 399                 valid_stack_ra_code_objects[num_valid_stack_ra_locations++] =
 400                     (lispobj *)((int)start_addr + OTHER_POINTER_LOWTAG);
 401             } else {
 402                 if (valid_dynamic_space_pointer((void *)thing, start_addr)) {
 403                     gc_assert(num_valid_stack_locations < MAX_STACK_POINTERS);
 404                     valid_stack_locations[num_valid_stack_locations++] = sp;
 405                 }
 406             }
 407         }
 408     }
 409     if (pointer_filter_verbose) {
 410         fprintf(stderr, "number of valid stack pointers = %d\n",
 411                 num_valid_stack_locations);
 412         fprintf(stderr, "number of stack return addresses = %d\n",
 413                 num_valid_stack_ra_locations);
 414     }
 415 }
 416
 417 static void
 418 pscav_i386_stack(void)
 419 {
 420     int i;
 421
 422     for (i = 0; i < num_valid_stack_locations; i++)
 423         pscav(valid_stack_locations[i], 1, 0);
 424
 425     for (i = 0; i < num_valid_stack_ra_locations; i++) {
 426         lispobj code_obj = (lispobj)valid_stack_ra_code_objects[i];
 427         pscav(&code_obj, 1, 0);
 428         if (pointer_filter_verbose) {
 429             fprintf(stderr,"*C moved RA %x to %x; for code object %x to %x\n",
 430                     *valid_stack_ra_locations[i],
 431                     (int)(*valid_stack_ra_locations[i])
 432                     - ((int)valid_stack_ra_code_objects[i] - (int)code_obj),
 433                     (unsigned int) valid_stack_ra_code_objects[i], code_obj);
 434         }
 435         *valid_stack_ra_locations[i] =
 436             ((int)(*valid_stack_ra_locations[i])
 437              - ((int)valid_stack_ra_code_objects[i] - (int)code_obj));
 438     }
 439 }
 440 #endif
 441 #endif
 442
 443 \f
 444 static void
 445 pscav_later(lispobj *where, int count)
 446 {
 447     struct later *new;
 448
 449     if (count > LATERMAXCOUNT) {
 450         while (count > LATERMAXCOUNT) {
 451             pscav_later(where, LATERMAXCOUNT);
 452             count -= LATERMAXCOUNT;
 453             where += LATERMAXCOUNT;
 454         }
 455     }
 456     else {
 457         if (later_blocks == NULL || later_count == LATERBLOCKSIZE ||
 458             (later_count == LATERBLOCKSIZE-1 && count > 1)) {
 459             new  = (struct later *)malloc(sizeof(struct later));
 460             new->next = later_blocks;
 461             if (later_blocks && later_count < LATERBLOCKSIZE)
 462                 later_blocks->u[later_count].ptr = NULL;
 463             later_blocks = new;
 464             later_count = 0;
 465         }
 466
 467         if (count != 1)
 468             later_blocks->u[later_count++].count = count;
 469         later_blocks->u[later_count++].ptr = where;
 470     }
 471 }
 472
 473 static lispobj
 474 ptrans_boxed(lispobj thing, lispobj header, boolean constant)
 475 {
 476     int nwords;
 477     lispobj result, *new, *old;
 478
 479     nwords = 1 + HeaderValue(header);
 480
 481     /* Allocate it */
 482     old = (lispobj *)native_pointer(thing);
 483     new = newspace_alloc(nwords,constant);
 484
 485     /* Copy it. */
 486     bcopy(old, new, nwords * sizeof(lispobj));
 487
 488     /* Deposit forwarding pointer. */
 489     result = make_lispobj(new, lowtag_of(thing));
 490     *old = result;
 491
 492     /* Scavenge it. */
 493     pscav(new, nwords, constant);
 494
 495     return result;
 496 }
 497
 498 /* We need to look at the layout to see whether it is a pure structure
 499  * class, and only then can we transport as constant. If it is pure,
 500  * we can ALWAYS transport as a constant. */
 501 static lispobj
 502 ptrans_instance(lispobj thing, lispobj header, boolean /* ignored */ constant)
 503 {
 504     lispobj layout = ((struct instance *)native_pointer(thing))->slots[0];
 505     lispobj pure = ((struct instance *)native_pointer(layout))->slots[15];
 506
 507     switch (pure) {
 508     case T:
 509         return (ptrans_boxed(thing, header, 1));
 510     case NIL:
 511         return (ptrans_boxed(thing, header, 0));
 512     case 0:
 513         {
 514             /* Substructure: special case for the COMPACT-INFO-ENVs,
 515              * where the instance may have a point to the dynamic
 516              * space placed into it (e.g. the cache-name slot), but
 517              * the lists and arrays at the time of a purify can be
 518              * moved to the RO space. */
 519             int nwords;
 520             lispobj result, *new, *old;
 521
 522             nwords = 1 + HeaderValue(header);
 523
 524             /* Allocate it */
 525             old = (lispobj *)native_pointer(thing);
 526             new = newspace_alloc(nwords, 0); /*  inconstant */
 527
 528             /* Copy it. */
 529             bcopy(old, new, nwords * sizeof(lispobj));
 530
 531             /* Deposit forwarding pointer. */
 532             result = make_lispobj(new, lowtag_of(thing));
 533             *old = result;
 534
 535             /* Scavenge it. */
 536             pscav(new, nwords, 1);
 537
 538             return result;
 539         }
 540     default:
 541         gc_abort();
 542         return NIL; /* dummy value: return something ... */
 543     }
 544 }
 545
 546 static lispobj
 547 ptrans_fdefn(lispobj thing, lispobj header)
 548 {
 549     int nwords;
 550     lispobj result, *new, *old, oldfn;
 551     struct fdefn *fdefn;
 552
 553     nwords = 1 + HeaderValue(header);
 554
 555     /* Allocate it */
 556     old = (lispobj *)native_pointer(thing);
 557     new = newspace_alloc(nwords, 0);    /* inconstant */
 558
 559     /* Copy it. */
 560     bcopy(old, new, nwords * sizeof(lispobj));
 561
 562     /* Deposit forwarding pointer. */
 563     result = make_lispobj(new, lowtag_of(thing));
 564     *old = result;
 565
 566     /* Scavenge the function. */
 567     fdefn = (struct fdefn *)new;
 568     oldfn = fdefn->fun;
 569     pscav(&fdefn->fun, 1, 0);
 570     if ((char *)oldfn + FUN_RAW_ADDR_OFFSET == fdefn->raw_addr)
 571         fdefn->raw_addr = (char *)fdefn->fun + FUN_RAW_ADDR_OFFSET;
 572
 573     return result;
 574 }
 575
 576 static lispobj
 577 ptrans_unboxed(lispobj thing, lispobj header)
 578 {
 579     int nwords;
 580     lispobj result, *new, *old;
 581
 582     nwords = 1 + HeaderValue(header);
 583
 584     /* Allocate it */
 585     old = (lispobj *)native_pointer(thing);
 586     new = newspace_alloc(nwords,1);     /* always constant */
 587
 588     /* copy it. */
 589     bcopy(old, new, nwords * sizeof(lispobj));
 590
 591     /* Deposit forwarding pointer. */
 592     result = make_lispobj(new , lowtag_of(thing));
 593     *old = result;
 594
 595     return result;
 596 }
 597
 598 static lispobj
 599 ptrans_vector(lispobj thing, int bits, int extra,
 600               boolean boxed, boolean constant)
 601 {
 602     struct vector *vector;
 603     int nwords;
 604     lispobj result, *new;
 605
 606     vector = (struct vector *)native_pointer(thing);
 607     nwords = 2 + (CEILING((fixnum_value(vector->length)+extra)*bits,32)>>5);
 608
 609     new=newspace_alloc(nwords, (constant || !boxed));
 610     bcopy(vector, new, nwords * sizeof(lispobj));
 611
 612     result = make_lispobj(new, lowtag_of(thing));
 613     vector->header = result;
 614
 615     if (boxed)
 616         pscav(new, nwords, constant);
 617
 618     return result;
 619 }
 620
 621 #ifdef LISP_FEATURE_X86
 622 static void
 623 apply_code_fixups_during_purify(struct code *old_code, struct code *new_code)
 624 {
 625     int nheader_words, ncode_words, nwords;
 626     void  *constants_start_addr, *constants_end_addr;
 627     void  *code_start_addr, *code_end_addr;
 628     lispobj fixups = NIL;
 629     unsigned  displacement = (unsigned)new_code - (unsigned)old_code;
 630     struct vector *fixups_vector;
 631
 632     ncode_words = fixnum_value(new_code->code_size);
 633     nheader_words = HeaderValue(*(lispobj *)new_code);
 634     nwords = ncode_words + nheader_words;
 635
 636     constants_start_addr = (void *)new_code + 5*4;
 637     constants_end_addr = (void *)new_code + nheader_words*4;
 638     code_start_addr = (void *)new_code + nheader_words*4;
 639     code_end_addr = (void *)new_code + nwords*4;
 640
 641     /* The first constant should be a pointer to the fixups for this
 642      * code objects. Check. */
 643     fixups = new_code->constants[0];
 644
 645     /* It will be 0 or the unbound-marker if there are no fixups, and
 646      * will be an other-pointer to a vector if it is valid. */
 647     if ((fixups==0) ||
 648         (fixups==UNBOUND_MARKER_WIDETAG) ||
 649         !is_lisp_pointer(fixups)) {
 650 #ifdef LISP_FEATURE_GENCGC
 651         /* Check for a possible errors. */
 652         sniff_code_object(new_code,displacement);
 653 #endif
 654         return;
 655     }
 656
 657     fixups_vector = (struct vector *)native_pointer(fixups);
 658
 659     /* Could be pointing to a forwarding pointer. */
 660     if (is_lisp_pointer(fixups) && (dynamic_pointer_p(fixups))
 661         && forwarding_pointer_p(*(lispobj *)fixups_vector)) {
 662         /* If so then follow it. */
 663         fixups_vector =
 664             (struct vector *)native_pointer(*(lispobj *)fixups_vector);
 665     }
 666
 667     if (widetag_of(fixups_vector->header) ==
 668         SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG) {
 669         /* We got the fixups for the code block. Now work through the
 670          * vector, and apply a fixup at each address. */
 671         int length = fixnum_value(fixups_vector->length);
 672         int i;
 673         for (i=0; i<length; i++) {
 674             unsigned offset = fixups_vector->data[i];
 675             /* Now check the current value of offset. */
 676             unsigned old_value =
 677                 *(unsigned *)((unsigned)code_start_addr + offset);
 678
 679             /* If it's within the old_code object then it must be an
 680              * absolute fixup (relative ones are not saved) */
 681             if ((old_value>=(unsigned)old_code)
 682                 && (old_value<((unsigned)old_code + nwords*4)))
 683                 /* So add the dispacement. */
 684                 *(unsigned *)((unsigned)code_start_addr + offset) = old_value
 685                     + displacement;
 686             else
 687                 /* It is outside the old code object so it must be a relative
 688                  * fixup (absolute fixups are not saved). So subtract the
 689                  * displacement. */
 690                 *(unsigned *)((unsigned)code_start_addr + offset) = old_value
 691                     - displacement;
 692         }
 693     }
 694
 695     /* No longer need the fixups. */
 696     new_code->constants[0] = 0;
 697
 698 #ifdef LISP_FEATURE_GENCGC
 699     /* Check for possible errors. */
 700     sniff_code_object(new_code,displacement);
 701 #endif
 702 }
 703 #endif
 704
 705 static lispobj
 706 ptrans_code(lispobj thing)
 707 {
 708     struct code *code, *new;
 709     int nwords;
 710     lispobj func, result;
 711
 712     code = (struct code *)native_pointer(thing);
 713     nwords = HeaderValue(code->header) + fixnum_value(code->code_size);
 714
 715     new = (struct code *)newspace_alloc(nwords,1); /* constant */
 716
 717     bcopy(code, new, nwords * sizeof(lispobj));
 718
 719 #ifdef LISP_FEATURE_X86
 720     apply_code_fixups_during_purify(code,new);
 721 #endif
 722
 723     result = make_lispobj(new, OTHER_POINTER_LOWTAG);
 724
 725     /* Stick in a forwarding pointer for the code object. */
 726     *(lispobj *)code = result;
 727
 728     /* Put in forwarding pointers for all the functions. */
 729     for (func = code->entry_points;
 730          func != NIL;
 731          func = ((struct simple_fun *)native_pointer(func))->next) {
 732
 733         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
 734
 735         *(lispobj *)native_pointer(func) = result + (func - thing);
 736     }
 737
 738     /* Arrange to scavenge the debug info later. */
 739     pscav_later(&new->debug_info, 1);
 740
 741     /* FIXME: why would this be a fixnum? */
 742     /* "why" is a hard word, but apparently for compiled functions the
 743        trace_table_offset contains the length of the instructions, as
 744        a fixnum.  See CODE-INST-AREA-LENGTH in
 745        src/compiler/target-disassem.lisp.  -- CSR, 2004-01-08 */
 746     if (!(fixnump(new->trace_table_offset)))
 747 #if 0
 748         pscav(&new->trace_table_offset, 1, 0);
 749 #else
 750         new->trace_table_offset = NIL; /* limit lifetime */
 751 #endif
 752
 753     /* Scavenge the constants. */
 754     pscav(new->constants, HeaderValue(new->header)-5, 1);
 755
 756     /* Scavenge all the functions. */
 757     pscav(&new->entry_points, 1, 1);
 758     for (func = new->entry_points;
 759          func != NIL;
 760          func = ((struct simple_fun *)native_pointer(func))->next) {
 761         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
 762         gc_assert(!dynamic_pointer_p(func));
 763
 764 #ifdef LISP_FEATURE_X86
 765         /* Temporarily convert the self pointer to a real function pointer. */
 766         ((struct simple_fun *)native_pointer(func))->self
 767             -= FUN_RAW_ADDR_OFFSET;
 768 #endif
 769         pscav(&((struct simple_fun *)native_pointer(func))->self, 2, 1);
 770 #ifdef LISP_FEATURE_X86
 771         ((struct simple_fun *)native_pointer(func))->self
 772             += FUN_RAW_ADDR_OFFSET;
 773 #endif
 774         pscav_later(&((struct simple_fun *)native_pointer(func))->name, 3);
 775     }
 776
 777     return result;
 778 }
 779
 780 static lispobj
 781 ptrans_func(lispobj thing, lispobj header)
 782 {
 783     int nwords;
 784     lispobj code, *new, *old, result;
 785     struct simple_fun *function;
 786
 787     /* Thing can either be a function header, a closure function
 788      * header, a closure, or a funcallable-instance. If it's a closure
 789      * or a funcallable-instance, we do the same as ptrans_boxed.
 790      * Otherwise we have to do something strange, 'cause it is buried
 791      * inside a code object. */
 792
 793     if (widetag_of(header) == SIMPLE_FUN_HEADER_WIDETAG) {
 794
 795         /* We can only end up here if the code object has not been
 796          * scavenged, because if it had been scavenged, forwarding pointers
 797          * would have been left behind for all the entry points. */
 798
 799         function = (struct simple_fun *)native_pointer(thing);
 800         code =
 801             make_lispobj
 802             ((native_pointer(thing) -
 803               (HeaderValue(function->header))), OTHER_POINTER_LOWTAG);
 804
 805         /* This will cause the function's header to be replaced with a
 806          * forwarding pointer. */
 807
 808         ptrans_code(code);
 809
 810         /* So we can just return that. */
 811         return function->header;
 812     }
 813     else {
 814         /* It's some kind of closure-like thing. */
 815         nwords = 1 + HeaderValue(header);
 816         old = (lispobj *)native_pointer(thing);
 817
 818         /* Allocate the new one.  FINs *must* not go in read_only
 819          * space.  Closures can; they never change */
 820
 821         new = newspace_alloc
 822             (nwords,(widetag_of(header)!=FUNCALLABLE_INSTANCE_HEADER_WIDETAG));
 823
 824         /* Copy it. */
 825         bcopy(old, new, nwords * sizeof(lispobj));
 826
 827         /* Deposit forwarding pointer. */
 828         result = make_lispobj(new, lowtag_of(thing));
 829         *old = result;
 830
 831         /* Scavenge it. */
 832         pscav(new, nwords, 0);
 833
 834         return result;
 835     }
 836 }
 837
 838 static lispobj
 839 ptrans_returnpc(lispobj thing, lispobj header)
 840 {
 841     lispobj code, new;
 842
 843     /* Find the corresponding code object. */
 844     code = thing - HeaderValue(header)*sizeof(lispobj);
 845
 846     /* Make sure it's been transported. */
 847     new = *(lispobj *)native_pointer(code);
 848     if (!forwarding_pointer_p(new))
 849         new = ptrans_code(code);
 850
 851     /* Maintain the offset: */
 852     return new + (thing - code);
 853 }
 854
 855 #define WORDS_PER_CONS CEILING(sizeof(struct cons) / sizeof(lispobj), 2)
 856
 857 static lispobj
 858 ptrans_list(lispobj thing, boolean constant)
 859 {
 860     struct cons *old, *new, *orig;
 861     int length;
 862
 863     orig = (struct cons *) newspace_alloc(0,constant);
 864     length = 0;
 865
 866     do {
 867         /* Allocate a new cons cell. */
 868         old = (struct cons *)native_pointer(thing);
 869         new = (struct cons *) newspace_alloc(WORDS_PER_CONS,constant);
 870
 871         /* Copy the cons cell and keep a pointer to the cdr. */
 872         new->car = old->car;
 873         thing = new->cdr = old->cdr;
 874
 875         /* Set up the forwarding pointer. */
 876         *(lispobj *)old = make_lispobj(new, LIST_POINTER_LOWTAG);
 877
 878         /* And count this cell. */
 879         length++;
 880     } while (lowtag_of(thing) == LIST_POINTER_LOWTAG &&
 881              dynamic_pointer_p(thing) &&
 882              !(forwarding_pointer_p(*(lispobj *)native_pointer(thing))));
 883
 884     /* Scavenge the list we just copied. */
 885     pscav((lispobj *)orig, length * WORDS_PER_CONS, constant);
 886
 887     return make_lispobj(orig, LIST_POINTER_LOWTAG);
 888 }
 889
 890 static lispobj
 891 ptrans_otherptr(lispobj thing, lispobj header, boolean constant)
 892 {
 893     switch (widetag_of(header)) {
 894         /* FIXME: this needs a reindent */
 895       case BIGNUM_WIDETAG:
 896       case SINGLE_FLOAT_WIDETAG:
 897       case DOUBLE_FLOAT_WIDETAG:
 898 #ifdef LONG_FLOAT_WIDETAG
 899       case LONG_FLOAT_WIDETAG:
 900 #endif
 901 #ifdef COMPLEX_SINGLE_FLOAT_WIDETAG
 902       case COMPLEX_SINGLE_FLOAT_WIDETAG:
 903 #endif
 904 #ifdef COMPLEX_DOUBLE_FLOAT_WIDETAG
 905       case COMPLEX_DOUBLE_FLOAT_WIDETAG:
 906 #endif
 907 #ifdef COMPLEX_LONG_FLOAT_WIDETAG
 908       case COMPLEX_LONG_FLOAT_WIDETAG:
 909 #endif
 910       case SAP_WIDETAG:
 911           return ptrans_unboxed(thing, header);
 912
 913       case RATIO_WIDETAG:
 914       case COMPLEX_WIDETAG:
 915       case SIMPLE_ARRAY_WIDETAG:
 916       case COMPLEX_BASE_STRING_WIDETAG:
 917       case COMPLEX_BIT_VECTOR_WIDETAG:
 918       case COMPLEX_VECTOR_NIL_WIDETAG:
 919       case COMPLEX_VECTOR_WIDETAG:
 920       case COMPLEX_ARRAY_WIDETAG:
 921         return ptrans_boxed(thing, header, constant);
 922
 923       case VALUE_CELL_HEADER_WIDETAG:
 924       case WEAK_POINTER_WIDETAG:
 925         return ptrans_boxed(thing, header, 0);
 926
 927       case SYMBOL_HEADER_WIDETAG:
 928         return ptrans_boxed(thing, header, 0);
 929
 930       case SIMPLE_ARRAY_NIL_WIDETAG:
 931         return ptrans_vector(thing, 0, 0, 0, constant);
 932
 933       case SIMPLE_BASE_STRING_WIDETAG:
 934         return ptrans_vector(thing, 8, 1, 0, constant);
 935
 936       case SIMPLE_BIT_VECTOR_WIDETAG:
 937         return ptrans_vector(thing, 1, 0, 0, constant);
 938
 939       case SIMPLE_VECTOR_WIDETAG:
 940         return ptrans_vector(thing, 32, 0, 1, constant);
 941
 942       case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
 943         return ptrans_vector(thing, 2, 0, 0, constant);
 944
 945       case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
 946         return ptrans_vector(thing, 4, 0, 0, constant);
 947
 948       case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
 949 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
 950       case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
 951       case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
 952 #endif
 953         return ptrans_vector(thing, 8, 0, 0, constant);
 954
 955       case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
 956 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
 957       case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
 958       case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
 959 #endif
 960         return ptrans_vector(thing, 16, 0, 0, constant);
 961
 962       case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
 963 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
 964       case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
 965       case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
 966 #endif
 967 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
 968       case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
 969       case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
 970 #endif
 971         return ptrans_vector(thing, 32, 0, 0, constant);
 972
 973       case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
 974         return ptrans_vector(thing, 32, 0, 0, constant);
 975
 976       case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
 977         return ptrans_vector(thing, 64, 0, 0, constant);
 978
 979 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
 980       case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
 981 #ifdef LISP_FEATURE_X86
 982         return ptrans_vector(thing, 96, 0, 0, constant);
 983 #endif
 984 #ifdef sparc
 985         return ptrans_vector(thing, 128, 0, 0, constant);
 986 #endif
 987 #endif
 988
 989 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
 990       case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
 991         return ptrans_vector(thing, 64, 0, 0, constant);
 992 #endif
 993
 994 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
 995       case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
 996         return ptrans_vector(thing, 128, 0, 0, constant);
 997 #endif
 998
 999 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
1000       case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
1001 #ifdef LISP_FEATURE_X86
1002         return ptrans_vector(thing, 192, 0, 0, constant);
1003 #endif
1004 #ifdef sparc
1005         return ptrans_vector(thing, 256, 0, 0, constant);
1006 #endif
1007 #endif
1008
1009       case CODE_HEADER_WIDETAG:
1010         return ptrans_code(thing);
1011
1012       case RETURN_PC_HEADER_WIDETAG:
1013         return ptrans_returnpc(thing, header);
1014
1015       case FDEFN_WIDETAG:
1016         return ptrans_fdefn(thing, header);
1017
1018       default:
1019         /* Should only come across other pointers to the above stuff. */
1020         gc_abort();
1021         return NIL;
1022     }
1023 }
1024
1025 static int
1026 pscav_fdefn(struct fdefn *fdefn)
1027 {
1028     boolean fix_func;
1029
1030     fix_func = ((char *)(fdefn->fun+FUN_RAW_ADDR_OFFSET) == fdefn->raw_addr);
1031     pscav(&fdefn->name, 1, 1);
1032     pscav(&fdefn->fun, 1, 0);
1033     if (fix_func)
1034         fdefn->raw_addr = (char *)(fdefn->fun + FUN_RAW_ADDR_OFFSET);
1035     return sizeof(struct fdefn) / sizeof(lispobj);
1036 }
1037
1038 #ifdef LISP_FEATURE_X86
1039 /* now putting code objects in static space */
1040 static int
1041 pscav_code(struct code*code)
1042 {
1043     int nwords;
1044     lispobj func;
1045     nwords = HeaderValue(code->header) + fixnum_value(code->code_size);
1046
1047     /* Arrange to scavenge the debug info later. */
1048     pscav_later(&code->debug_info, 1);
1049
1050     /* Scavenge the constants. */
1051     pscav(code->constants, HeaderValue(code->header)-5, 1);
1052
1053     /* Scavenge all the functions. */
1054     pscav(&code->entry_points, 1, 1);
1055     for (func = code->entry_points;
1056          func != NIL;
1057          func = ((struct simple_fun *)native_pointer(func))->next) {
1058         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
1059         gc_assert(!dynamic_pointer_p(func));
1060
1061 #ifdef LISP_FEATURE_X86
1062         /* Temporarily convert the self pointer to a real function
1063          * pointer. */
1064         ((struct simple_fun *)native_pointer(func))->self
1065             -= FUN_RAW_ADDR_OFFSET;
1066 #endif
1067         pscav(&((struct simple_fun *)native_pointer(func))->self, 2, 1);
1068 #ifdef LISP_FEATURE_X86
1069         ((struct simple_fun *)native_pointer(func))->self
1070             += FUN_RAW_ADDR_OFFSET;
1071 #endif
1072         pscav_later(&((struct simple_fun *)native_pointer(func))->name, 3);
1073     }
1074
1075     return CEILING(nwords,2);
1076 }
1077 #endif
1078
1079 static lispobj *
1080 pscav(lispobj *addr, int nwords, boolean constant)
1081 {
1082     lispobj thing, *thingp, header;
1083     int count = 0; /* (0 = dummy init value to stop GCC warning) */
1084     struct vector *vector;
1085
1086     while (nwords > 0) {
1087         thing = *addr;
1088         if (is_lisp_pointer(thing)) {
1089             /* It's a pointer. Is it something we might have to move? */
1090             if (dynamic_pointer_p(thing)) {
1091                 /* Maybe. Have we already moved it? */
1092                 thingp = (lispobj *)native_pointer(thing);
1093                 header = *thingp;
1094                 if (is_lisp_pointer(header) && forwarding_pointer_p(header))
1095                     /* Yep, so just copy the forwarding pointer. */
1096                     thing = header;
1097                 else {
1098                     /* Nope, copy the object. */
1099                     switch (lowtag_of(thing)) {
1100                       case FUN_POINTER_LOWTAG:
1101                         thing = ptrans_func(thing, header);
1102                         break;
1103
1104                       case LIST_POINTER_LOWTAG:
1105                         thing = ptrans_list(thing, constant);
1106                         break;
1107
1108                       case INSTANCE_POINTER_LOWTAG:
1109                         thing = ptrans_instance(thing, header, constant);
1110                         break;
1111
1112                       case OTHER_POINTER_LOWTAG:
1113                         thing = ptrans_otherptr(thing, header, constant);
1114                         break;
1115
1116                       default:
1117                         /* It was a pointer, but not one of them? */
1118                         gc_abort();
1119                     }
1120                 }
1121                 *addr = thing;
1122             }
1123             count = 1;
1124         }
1125         else if (thing & 3) {   /* FIXME: 3?  not 2? */
1126             /* It's an other immediate. Maybe the header for an unboxed */
1127             /* object. */
1128             switch (widetag_of(thing)) {
1129               case BIGNUM_WIDETAG:
1130               case SINGLE_FLOAT_WIDETAG:
1131               case DOUBLE_FLOAT_WIDETAG:
1132 #ifdef LONG_FLOAT_WIDETAG
1133               case LONG_FLOAT_WIDETAG:
1134 #endif
1135               case SAP_WIDETAG:
1136                 /* It's an unboxed simple object. */
1137                 count = HeaderValue(thing)+1;
1138                 break;
1139
1140               case SIMPLE_VECTOR_WIDETAG:
1141                   if (HeaderValue(thing) == subtype_VectorValidHashing) {
1142                     *addr = (subtype_VectorMustRehash << N_WIDETAG_BITS) |
1143                         SIMPLE_VECTOR_WIDETAG;
1144                   }
1145                 count = 1;
1146                 break;
1147
1148               case SIMPLE_ARRAY_NIL_WIDETAG:
1149                 count = 2;
1150                 break;
1151
1152               case SIMPLE_BASE_STRING_WIDETAG:
1153                 vector = (struct vector *)addr;
1154                 count = CEILING(NWORDS(fixnum_value(vector->length)+1,4)+2,2);
1155                 break;
1156
1157               case SIMPLE_BIT_VECTOR_WIDETAG:
1158                 vector = (struct vector *)addr;
1159                 count = CEILING(NWORDS(fixnum_value(vector->length),32)+2,2);
1160                 break;
1161
1162               case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
1163                 vector = (struct vector *)addr;
1164                 count = CEILING(NWORDS(fixnum_value(vector->length),16)+2,2);
1165                 break;
1166
1167               case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
1168                 vector = (struct vector *)addr;
1169                 count = CEILING(NWORDS(fixnum_value(vector->length),8)+2,2);
1170                 break;
1171
1172               case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
1173 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
1174               case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
1175               case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
1176 #endif
1177                 vector = (struct vector *)addr;
1178                 count = CEILING(NWORDS(fixnum_value(vector->length),4)+2,2);
1179                 break;
1180
1181               case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
1182 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
1183               case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
1184               case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
1185 #endif
1186                 vector = (struct vector *)addr;
1187                 count = CEILING(NWORDS(fixnum_value(vector->length),2)+2,2);
1188                 break;
1189
1190               case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
1191 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
1192               case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
1193               case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
1194 #endif
1195 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
1196               case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
1197               case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
1198 #endif
1199                 vector = (struct vector *)addr;
1200                 count = CEILING(fixnum_value(vector->length)+2,2);
1201                 break;
1202
1203               case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
1204                 vector = (struct vector *)addr;
1205                 count = CEILING(fixnum_value(vector->length)+2,2);
1206                 break;
1207
1208               case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
1209 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
1210               case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
1211 #endif
1212                 vector = (struct vector *)addr;
1213                 count = fixnum_value(vector->length)*2+2;
1214                 break;
1215
1216 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
1217               case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
1218                 vector = (struct vector *)addr;
1219 #ifdef LISP_FEATURE_X86
1220                 count = fixnum_value(vector->length)*3+2;
1221 #endif
1222 #ifdef sparc
1223                 count = fixnum_value(vector->length)*4+2;
1224 #endif
1225                 break;
1226 #endif
1227
1228 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
1229               case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
1230                 vector = (struct vector *)addr;
1231                 count = fixnum_value(vector->length)*4+2;
1232                 break;
1233 #endif
1234
1235 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
1236               case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
1237                 vector = (struct vector *)addr;
1238 #ifdef LISP_FEATURE_X86
1239                 count = fixnum_value(vector->length)*6+2;
1240 #endif
1241 #ifdef sparc
1242                 count = fixnum_value(vector->length)*8+2;
1243 #endif
1244                 break;
1245 #endif
1246
1247               case CODE_HEADER_WIDETAG:
1248 #ifndef LISP_FEATURE_X86
1249                 gc_abort(); /* no code headers in static space */
1250 #else
1251                 count = pscav_code((struct code*)addr);
1252 #endif
1253                 break;
1254
1255               case SIMPLE_FUN_HEADER_WIDETAG:
1256               case RETURN_PC_HEADER_WIDETAG:
1257                 /* We should never hit any of these, 'cause they occur
1258                  * buried in the middle of code objects. */
1259                 gc_abort();
1260                 break;
1261
1262 #ifdef LISP_FEATURE_X86
1263               case CLOSURE_HEADER_WIDETAG:
1264               case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
1265                 /* The function self pointer needs special care on the
1266                  * x86 because it is the real entry point. */
1267                 {
1268                   lispobj fun = ((struct closure *)addr)->fun
1269                     - FUN_RAW_ADDR_OFFSET;
1270                   pscav(&fun, 1, constant);
1271                   ((struct closure *)addr)->fun = fun + FUN_RAW_ADDR_OFFSET;
1272                 }
1273                 count = 2;
1274                 break;
1275 #endif
1276
1277               case WEAK_POINTER_WIDETAG:
1278                 /* Weak pointers get preserved during purify, 'cause I
1279                  * don't feel like figuring out how to break them. */
1280                 pscav(addr+1, 2, constant);
1281                 count = 4;
1282                 break;
1283
1284               case FDEFN_WIDETAG:
1285                 /* We have to handle fdefn objects specially, so we
1286                  * can fix up the raw function address. */
1287                 count = pscav_fdefn((struct fdefn *)addr);
1288                 break;
1289
1290               default:
1291                 count = 1;
1292                 break;
1293             }
1294         }
1295         else {
1296             /* It's a fixnum. */
1297             count = 1;
1298         }
1299
1300         addr += count;
1301         nwords -= count;
1302     }
1303
1304     return addr;
1305 }
1306
1307 int
1308 purify(lispobj static_roots, lispobj read_only_roots)
1309 {
1310     lispobj *clean;
1311     int count, i;
1312     struct later *laters, *next;
1313     struct thread *thread;
1314
1315     if(all_threads->next) {
1316         /* FIXME: there should be _some_ sensible error reporting
1317          * convention.  See following comment too */
1318         fprintf(stderr,"Can't purify when more than one thread exists\n");
1319         fflush(stderr);
1320         return 0;
1321     }
1322
1323 #ifdef PRINTNOISE
1324     printf("[doing purification:");
1325     fflush(stdout);
1326 #endif
1327 #ifdef LISP_FEATURE_GENCGC
1328     gc_alloc_update_all_page_tables();
1329 #endif
1330     for_each_thread(thread)
1331         if (fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread)) != 0) {
1332         /* FIXME: 1. What does this mean? 2. It shouldn't be reporting
1333          * its error simply by a. printing a string b. to stdout instead
1334          * of stderr. */
1335         printf(" Ack! Can't purify interrupt contexts. ");
1336         fflush(stdout);
1337         return 0;
1338     }
1339
1340 #if defined(LISP_FEATURE_X86)
1341     dynamic_space_free_pointer =
1342       (lispobj*)SymbolValue(ALLOCATION_POINTER,0);
1343 #endif
1344
1345     read_only_end = read_only_free =
1346         (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER,0);
1347     static_end = static_free =
1348         (lispobj *)SymbolValue(STATIC_SPACE_FREE_POINTER,0);
1349
1350 #ifdef PRINTNOISE
1351     printf(" roots");
1352     fflush(stdout);
1353 #endif
1354
1355 #if (defined(LISP_FEATURE_GENCGC) && defined(LISP_FEATURE_X86))
1356     /* note this expects only one thread to be active.  We'd have to
1357      * stop all the others in the same way as GC does if we wanted
1358      * PURIFY to work when >1 thread exists */
1359     setup_i386_stack_scav(((&static_roots)-2),
1360                           ((void *)all_threads->control_stack_end));
1361 #endif
1362
1363     pscav(&static_roots, 1, 0);
1364     pscav(&read_only_roots, 1, 1);
1365
1366 #ifdef PRINTNOISE
1367     printf(" handlers");
1368     fflush(stdout);
1369 #endif
1370     pscav((lispobj *) all_threads->interrupt_data->interrupt_handlers,
1371           sizeof(all_threads->interrupt_data->interrupt_handlers)
1372           / sizeof(lispobj),
1373           0);
1374
1375 #ifdef PRINTNOISE
1376     printf(" stack");
1377     fflush(stdout);
1378 #endif
1379 #ifndef LISP_FEATURE_X86
1380     pscav((lispobj *)all_threads->control_stack_start,
1381           current_control_stack_pointer -
1382           all_threads->control_stack_start,
1383           0);
1384 #else
1385 #ifdef LISP_FEATURE_GENCGC
1386     pscav_i386_stack();
1387 #endif
1388 #endif
1389
1390 #ifdef PRINTNOISE
1391     printf(" bindings");
1392     fflush(stdout);
1393 #endif
1394 #if !defined(LISP_FEATURE_X86)
1395     pscav( (lispobj *)all_threads->binding_stack_start,
1396           (lispobj *)current_binding_stack_pointer -
1397            all_threads->binding_stack_start,
1398           0);
1399 #else
1400     for_each_thread(thread) {
1401         pscav( (lispobj *)thread->binding_stack_start,
1402                (lispobj *)SymbolValue(BINDING_STACK_POINTER,thread) -
1403                (lispobj *)thread->binding_stack_start,
1404           0);
1405         pscav( (lispobj *) (thread+1),
1406                fixnum_value(SymbolValue(FREE_TLS_INDEX,0)) -
1407                (sizeof (struct thread))/(sizeof (lispobj)),
1408           0);
1409     }
1410
1411
1412 #endif
1413
1414     /* The original CMU CL code had scavenge-read-only-space code
1415      * controlled by the Lisp-level variable
1416      * *SCAVENGE-READ-ONLY-SPACE*. It was disabled by default, and it
1417      * wasn't documented under what circumstances it was useful or
1418      * safe to turn it on, so it's been turned off in SBCL. If you
1419      * want/need this functionality, and can test and document it,
1420      * please submit a patch. */
1421 #if 0
1422     if (SymbolValue(SCAVENGE_READ_ONLY_SPACE) != UNBOUND_MARKER_WIDETAG
1423         && SymbolValue(SCAVENGE_READ_ONLY_SPACE) != NIL) {
1424       unsigned  read_only_space_size =
1425           (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER) -
1426           (lispobj *)READ_ONLY_SPACE_START;
1427       fprintf(stderr,
1428               "scavenging read only space: %d bytes\n",
1429               read_only_space_size * sizeof(lispobj));
1430       pscav( (lispobj *)READ_ONLY_SPACE_START, read_only_space_size, 0);
1431     }
1432 #endif
1433
1434 #ifdef PRINTNOISE
1435     printf(" static");
1436     fflush(stdout);
1437 #endif
1438     clean = (lispobj *)STATIC_SPACE_START;
1439     do {
1440         while (clean != static_free)
1441             clean = pscav(clean, static_free - clean, 0);
1442         laters = later_blocks;
1443         count = later_count;
1444         later_blocks = NULL;
1445         later_count = 0;
1446         while (laters != NULL) {
1447             for (i = 0; i < count; i++) {
1448                 if (laters->u[i].count == 0) {
1449                     ;
1450                 } else if (laters->u[i].count <= LATERMAXCOUNT) {
1451                     pscav(laters->u[i+1].ptr, laters->u[i].count, 1);
1452                     i++;
1453                 } else {
1454                     pscav(laters->u[i].ptr, 1, 1);
1455                 }
1456             }
1457             next = laters->next;
1458             free(laters);
1459             laters = next;
1460             count = LATERBLOCKSIZE;
1461         }
1462     } while (clean != static_free || later_blocks != NULL);
1463
1464 #ifdef PRINTNOISE
1465     printf(" cleanup");
1466     fflush(stdout);
1467 #endif
1468
1469     os_zero((os_vm_address_t) current_dynamic_space,
1470             (os_vm_size_t) DYNAMIC_SPACE_SIZE);
1471
1472     /* Zero the stack. Note that the stack is also zeroed by SUB-GC
1473      * calling SCRUB-CONTROL-STACK - this zeros the stack on the x86. */
1474 #ifndef LISP_FEATURE_X86
1475     os_zero((os_vm_address_t) current_control_stack_pointer,
1476             (os_vm_size_t)
1477             ((all_threads->control_stack_end -
1478               current_control_stack_pointer) * sizeof(lispobj)));
1479 #endif
1480
1481     /* It helps to update the heap free pointers so that free_heap can
1482      * verify after it's done. */
1483     SetSymbolValue(READ_ONLY_SPACE_FREE_POINTER, (lispobj)read_only_free,0);
1484     SetSymbolValue(STATIC_SPACE_FREE_POINTER, (lispobj)static_free,0);
1485
1486 #if !defined(ALLOCATION_POINTER)
1487     dynamic_space_free_pointer = current_dynamic_space;
1488     set_auto_gc_trigger(bytes_consed_between_gcs);
1489 #else
1490 #if defined LISP_FEATURE_GENCGC
1491     gc_free_heap();
1492 #else
1493 #error unsupported case /* in CMU CL, was "ibmrt using GC" */
1494 #endif
1495 #endif
1496
1497 #ifdef PRINTNOISE
1498     printf(" done]\n");
1499     fflush(stdout);
1500 #endif
1501     return 0;
1502 }