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 #define PRINTNOISE
  39
  40 extern unsigned long bytes_consed_between_gcs;
  41
  42 static lispobj *dynamic_space_purify_pointer;
  43
  44 \f
  45 /* These hold the original end of the read_only and static spaces so
  46  * we can tell what are forwarding pointers. */
  47
  48 static lispobj *read_only_end, *static_end;
  49
  50 static lispobj *read_only_free, *static_free;
  51
  52 static lispobj *pscav(lispobj *addr, long nwords, boolean constant);
  53
  54 #define LATERBLOCKSIZE 1020
  55 #define LATERMAXCOUNT 10
  56
  57 static struct
  58 later {
  59     struct later *next;
  60     union {
  61         lispobj *ptr;
  62         long count;
  63     } u[LATERBLOCKSIZE];
  64 } *later_blocks = NULL;
  65 static long later_count = 0;
  66
  67 #if N_WORD_BITS == 32
  68  #define SIMPLE_ARRAY_WORD_WIDETAG SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG
  69 #elif N_WORD_BITS == 64
  70  #define SIMPLE_ARRAY_WORD_WIDETAG SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG
  71 #endif
  72
  73 /* FIXME: Shouldn't this be defined in sbcl.h?  See also notes in
  74  * cheneygc.c */
  75
  76 #ifdef LISP_FEATURE_SPARC
  77 #define FUN_RAW_ADDR_OFFSET 0
  78 #else
  79 #define FUN_RAW_ADDR_OFFSET (6*sizeof(lispobj) - FUN_POINTER_LOWTAG)
  80 #endif
  81 \f
  82 static boolean
  83 forwarding_pointer_p(lispobj obj)
  84 {
  85     lispobj *ptr = native_pointer(obj);
  86
  87     return ((static_end <= ptr && ptr <= static_free) ||
  88             (read_only_end <= ptr && ptr <= read_only_free));
  89 }
  90
  91 static boolean
  92 dynamic_pointer_p(lispobj ptr)
  93 {
  94 #ifndef LISP_FEATURE_GENCGC
  95     return (ptr >= (lispobj)current_dynamic_space
  96             &&
  97             ptr < (lispobj)dynamic_space_purify_pointer);
  98 #else
  99     /* Be more conservative, and remember, this is a maybe. */
 100     return (ptr >= (lispobj)DYNAMIC_SPACE_START
 101             &&
 102             ptr < (lispobj)dynamic_space_purify_pointer);
 103 #endif
 104 }
 105
 106 static inline lispobj *
 107 newspace_alloc(long nwords, int constantp)
 108 {
 109     lispobj *ret;
 110     nwords=CEILING(nwords,2);
 111     if(constantp) {
 112         if(read_only_free + nwords >= (lispobj *)READ_ONLY_SPACE_END) {
 113             lose("Ran out of read-only space while purifying!\n");
 114         }
 115         ret=read_only_free;
 116         read_only_free+=nwords;
 117     } else {
 118         if(static_free + nwords >= (lispobj *)STATIC_SPACE_END) {
 119             lose("Ran out of static space while purifying!\n");
 120         }
 121         ret=static_free;
 122         static_free+=nwords;
 123     }
 124     return ret;
 125 }
 126
 127
 128 \f
 129 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 130
 131 #ifdef LISP_FEATURE_GENCGC
 132 /*
 133  * enhanced x86/GENCGC stack scavenging by Douglas Crosher
 134  *
 135  * Scavenging the stack on the i386 is problematic due to conservative
 136  * roots and raw return addresses. Here it is handled in two passes:
 137  * the first pass runs before any objects are moved and tries to
 138  * identify valid pointers and return address on the stack, the second
 139  * pass scavenges these.
 140  */
 141
 142 static unsigned pointer_filter_verbose = 0;
 143
 144 /* FIXME: This is substantially the same code as
 145  * possibly_valid_dynamic_space_pointer in gencgc.c.  The only
 146  * relevant difference seems to be that the gencgc code also checks
 147  * for raw pointers into Code objects, whereas in purify these are
 148  * checked separately in setup_i386_stack_scav - they go onto
 149  * valid_stack_ra_locations instead of just valid_stack_locations */
 150
 151 static int
 152 valid_dynamic_space_pointer(lispobj *pointer, lispobj *start_addr)
 153 {
 154     /* If it's not a return address then it needs to be a valid Lisp
 155      * pointer. */
 156     if (!is_lisp_pointer((lispobj)pointer))
 157         return 0;
 158
 159     /* Check that the object pointed to is consistent with the pointer
 160      * low tag. */
 161     switch (lowtag_of((lispobj)pointer)) {
 162     case FUN_POINTER_LOWTAG:
 163         /* Start_addr should be the enclosing code object, or a closure
 164          * header. */
 165         switch (widetag_of(*start_addr)) {
 166         case CODE_HEADER_WIDETAG:
 167             /* This case is probably caught above. */
 168             break;
 169         case CLOSURE_HEADER_WIDETAG:
 170         case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
 171             if ((long)pointer != ((long)start_addr+FUN_POINTER_LOWTAG)) {
 172                 if (pointer_filter_verbose) {
 173                     fprintf(stderr,"*Wf2: %p %p %p\n",
 174                             pointer, start_addr, (void *)*start_addr);
 175                 }
 176                 return 0;
 177             }
 178             break;
 179         default:
 180             if (pointer_filter_verbose) {
 181                 fprintf(stderr,"*Wf3: %p %p %p\n",
 182                         pointer, start_addr, (void *)*start_addr);
 183             }
 184             return 0;
 185         }
 186         break;
 187     case LIST_POINTER_LOWTAG:
 188         if ((long)pointer != ((long)start_addr+LIST_POINTER_LOWTAG)) {
 189             if (pointer_filter_verbose)
 190                 fprintf(stderr,"*Wl1: %p %p %p\n",
 191                         pointer, start_addr, (void *)*start_addr);
 192             return 0;
 193         }
 194         /* Is it plausible cons? */
 195         if ((is_lisp_pointer(start_addr[0])
 196             || ((start_addr[0] & FIXNUM_TAG_MASK) == 0) /* fixnum */
 197             || (widetag_of(start_addr[0]) == CHARACTER_WIDETAG)
 198 #if N_WORD_BITS == 64
 199             || (widetag_of(start_addr[0]) == SINGLE_FLOAT_WIDETAG)
 200 #endif
 201             || (widetag_of(start_addr[0]) == UNBOUND_MARKER_WIDETAG))
 202            && (is_lisp_pointer(start_addr[1])
 203                || ((start_addr[1] & FIXNUM_TAG_MASK) == 0) /* fixnum */
 204                || (widetag_of(start_addr[1]) == CHARACTER_WIDETAG)
 205 #if N_WORD_BITS == 64
 206                || (widetag_of(start_addr[1]) == SINGLE_FLOAT_WIDETAG)
 207 #endif
 208                || (widetag_of(start_addr[1]) == UNBOUND_MARKER_WIDETAG))) {
 209             break;
 210         } else {
 211             if (pointer_filter_verbose) {
 212                 fprintf(stderr,"*Wl2: %p %p %p\n",
 213                         pointer, start_addr, (void *)*start_addr);
 214             }
 215             return 0;
 216         }
 217     case INSTANCE_POINTER_LOWTAG:
 218         if ((long)pointer != ((long)start_addr+INSTANCE_POINTER_LOWTAG)) {
 219             if (pointer_filter_verbose) {
 220                 fprintf(stderr,"*Wi1: %p %p %p\n",
 221                         pointer, start_addr, (void *)*start_addr);
 222             }
 223             return 0;
 224         }
 225         if (widetag_of(start_addr[0]) != INSTANCE_HEADER_WIDETAG) {
 226             if (pointer_filter_verbose) {
 227                 fprintf(stderr,"*Wi2: %p %p %p\n",
 228                         pointer, start_addr, (void *)*start_addr);
 229             }
 230             return 0;
 231         }
 232         break;
 233     case OTHER_POINTER_LOWTAG:
 234         if ((long)pointer != ((long)start_addr+OTHER_POINTER_LOWTAG)) {
 235             if (pointer_filter_verbose) {
 236                 fprintf(stderr,"*Wo1: %p %p %p\n",
 237                         pointer, start_addr, (void *)*start_addr);
 238             }
 239             return 0;
 240         }
 241         /* Is it plausible? Not a cons. XXX should check the headers. */
 242         if (is_lisp_pointer(start_addr[0]) || ((start_addr[0] & FIXNUM_TAG_MASK) == 0)) {
 243             if (pointer_filter_verbose) {
 244                 fprintf(stderr,"*Wo2: %p %p %p\n",
 245                         pointer, start_addr, (void *)*start_addr);
 246             }
 247             return 0;
 248         }
 249         switch (widetag_of(start_addr[0])) {
 250         case UNBOUND_MARKER_WIDETAG:
 251         case CHARACTER_WIDETAG:
 252 #if N_WORD_BITS == 64
 253         case SINGLE_FLOAT_WIDETAG:
 254 #endif
 255             if (pointer_filter_verbose) {
 256                 fprintf(stderr,"*Wo3: %p %p %p\n",
 257                         pointer, start_addr, (void *)*start_addr);
 258             }
 259             return 0;
 260
 261             /* only pointed to by function pointers? */
 262         case CLOSURE_HEADER_WIDETAG:
 263         case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
 264             if (pointer_filter_verbose) {
 265                 fprintf(stderr,"*Wo4: %p %p %p\n",
 266                         pointer, start_addr, (void *)*start_addr);
 267             }
 268             return 0;
 269
 270         case INSTANCE_HEADER_WIDETAG:
 271             if (pointer_filter_verbose) {
 272                 fprintf(stderr,"*Wo5: %p %p %p\n",
 273                         pointer, start_addr, (void *)*start_addr);
 274             }
 275             return 0;
 276
 277             /* the valid other immediate pointer objects */
 278         case SIMPLE_VECTOR_WIDETAG:
 279         case RATIO_WIDETAG:
 280         case COMPLEX_WIDETAG:
 281 #ifdef COMPLEX_SINGLE_FLOAT_WIDETAG
 282         case COMPLEX_SINGLE_FLOAT_WIDETAG:
 283 #endif
 284 #ifdef COMPLEX_DOUBLE_FLOAT_WIDETAG
 285         case COMPLEX_DOUBLE_FLOAT_WIDETAG:
 286 #endif
 287 #ifdef COMPLEX_LONG_FLOAT_WIDETAG
 288         case COMPLEX_LONG_FLOAT_WIDETAG:
 289 #endif
 290         case SIMPLE_ARRAY_WIDETAG:
 291         case COMPLEX_BASE_STRING_WIDETAG:
 292 #ifdef COMPLEX_CHARACTER_STRING_WIDETAG
 293         case COMPLEX_CHARACTER_STRING_WIDETAG:
 294 #endif
 295         case COMPLEX_VECTOR_NIL_WIDETAG:
 296         case COMPLEX_BIT_VECTOR_WIDETAG:
 297         case COMPLEX_VECTOR_WIDETAG:
 298         case COMPLEX_ARRAY_WIDETAG:
 299         case VALUE_CELL_HEADER_WIDETAG:
 300         case SYMBOL_HEADER_WIDETAG:
 301         case FDEFN_WIDETAG:
 302         case CODE_HEADER_WIDETAG:
 303         case BIGNUM_WIDETAG:
 304 #if N_WORD_BITS != 64
 305         case SINGLE_FLOAT_WIDETAG:
 306 #endif
 307         case DOUBLE_FLOAT_WIDETAG:
 308 #ifdef LONG_FLOAT_WIDETAG
 309         case LONG_FLOAT_WIDETAG:
 310 #endif
 311         case SIMPLE_ARRAY_NIL_WIDETAG:
 312         case SIMPLE_BASE_STRING_WIDETAG:
 313 #ifdef SIMPLE_CHARACTER_STRING_WIDETAG
 314         case SIMPLE_CHARACTER_STRING_WIDETAG:
 315 #endif
 316         case SIMPLE_BIT_VECTOR_WIDETAG:
 317         case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
 318         case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
 319         case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
 320         case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
 321         case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
 322         case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
 323 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG
 324         case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
 325 #endif
 326         case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
 327         case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
 328 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_60_WIDETAG
 329                 case SIMPLE_ARRAY_UNSIGNED_BYTE_60_WIDETAG:
 330 #endif
 331 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_63_WIDETAG
 332                 case SIMPLE_ARRAY_UNSIGNED_BYTE_63_WIDETAG:
 333 #endif
 334 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG
 335                 case SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG:
 336 #endif
 337 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
 338         case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
 339 #endif
 340 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
 341         case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
 342 #endif
 343 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
 344         case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
 345 #endif
 346 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
 347         case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
 348 #endif
 349 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG
 350                 case SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG:
 351 #endif
 352 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG
 353                 case SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG:
 354 #endif
 355         case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
 356         case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
 357 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
 358         case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
 359 #endif
 360 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
 361         case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
 362 #endif
 363 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
 364         case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
 365 #endif
 366 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
 367         case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
 368 #endif
 369         case SAP_WIDETAG:
 370         case WEAK_POINTER_WIDETAG:
 371             break;
 372
 373         default:
 374             if (pointer_filter_verbose) {
 375                 fprintf(stderr,"*Wo6: %p %p %p\n",
 376                         pointer, start_addr, (void *)*start_addr);
 377             }
 378             return 0;
 379         }
 380         break;
 381     default:
 382         if (pointer_filter_verbose) {
 383             fprintf(stderr,"*W?: %p %p %p\n",
 384                     pointer, start_addr, (void *)*start_addr);
 385         }
 386         return 0;
 387     }
 388
 389     /* looks good */
 390     return 1;
 391 }
 392
 393 #define MAX_STACK_POINTERS 256
 394 lispobj *valid_stack_locations[MAX_STACK_POINTERS];
 395 unsigned long num_valid_stack_locations;
 396
 397 #define MAX_STACK_RETURN_ADDRESSES 128
 398 lispobj *valid_stack_ra_locations[MAX_STACK_RETURN_ADDRESSES];
 399 lispobj *valid_stack_ra_code_objects[MAX_STACK_RETURN_ADDRESSES];
 400 unsigned long num_valid_stack_ra_locations;
 401
 402 /* Identify valid stack slots. */
 403 static void
 404 setup_i386_stack_scav(lispobj *lowaddr, lispobj *base)
 405 {
 406     lispobj *sp = lowaddr;
 407     num_valid_stack_locations = 0;
 408     num_valid_stack_ra_locations = 0;
 409     for (sp = lowaddr; sp < base; sp++) {
 410         lispobj thing = *sp;
 411         /* Find the object start address */
 412         lispobj *start_addr = search_dynamic_space((void *)thing);
 413         if (start_addr) {
 414             /* We need to allow raw pointers into Code objects for
 415              * return addresses. This will also pick up pointers to
 416              * functions in code objects. */
 417             if (widetag_of(*start_addr) == CODE_HEADER_WIDETAG) {
 418                 /* FIXME asserting here is a really dumb thing to do.
 419                  * If we've overflowed some arbitrary static limit, we
 420                  * should just refuse to purify, instead of killing
 421                  * the whole lisp session
 422                  */
 423                 gc_assert(num_valid_stack_ra_locations <
 424                           MAX_STACK_RETURN_ADDRESSES);
 425                 valid_stack_ra_locations[num_valid_stack_ra_locations] = sp;
 426                 valid_stack_ra_code_objects[num_valid_stack_ra_locations++] =
 427                     (lispobj *)((long)start_addr + OTHER_POINTER_LOWTAG);
 428             } else {
 429                 if (valid_dynamic_space_pointer((void *)thing, start_addr)) {
 430                     gc_assert(num_valid_stack_locations < MAX_STACK_POINTERS);
 431                     valid_stack_locations[num_valid_stack_locations++] = sp;
 432                 }
 433             }
 434         }
 435     }
 436     if (pointer_filter_verbose) {
 437         fprintf(stderr, "number of valid stack pointers = %ld\n",
 438                 num_valid_stack_locations);
 439         fprintf(stderr, "number of stack return addresses = %ld\n",
 440                 num_valid_stack_ra_locations);
 441     }
 442 }
 443
 444 static void
 445 pscav_i386_stack(void)
 446 {
 447     long i;
 448
 449     for (i = 0; i < num_valid_stack_locations; i++)
 450         pscav(valid_stack_locations[i], 1, 0);
 451
 452     for (i = 0; i < num_valid_stack_ra_locations; i++) {
 453         lispobj code_obj = (lispobj)valid_stack_ra_code_objects[i];
 454         pscav(&code_obj, 1, 0);
 455         if (pointer_filter_verbose) {
 456             fprintf(stderr,"*C moved RA %p to %p; for code object %p to %p\n",
 457                     (void *)*valid_stack_ra_locations[i],
 458                     (void *)(*valid_stack_ra_locations[i]) -
 459                     ((void *)valid_stack_ra_code_objects[i] -
 460                      (void *)code_obj),
 461                     valid_stack_ra_code_objects[i], (void *)code_obj);
 462         }
 463         *valid_stack_ra_locations[i] =
 464             ((long)(*valid_stack_ra_locations[i])
 465              - ((long)valid_stack_ra_code_objects[i] - (long)code_obj));
 466     }
 467 }
 468 #endif
 469 #endif
 470
 471 \f
 472 static void
 473 pscav_later(lispobj *where, long count)
 474 {
 475     struct later *new;
 476
 477     if (count > LATERMAXCOUNT) {
 478         while (count > LATERMAXCOUNT) {
 479             pscav_later(where, LATERMAXCOUNT);
 480             count -= LATERMAXCOUNT;
 481             where += LATERMAXCOUNT;
 482         }
 483     }
 484     else {
 485         if (later_blocks == NULL || later_count == LATERBLOCKSIZE ||
 486             (later_count == LATERBLOCKSIZE-1 && count > 1)) {
 487             new  = (struct later *)malloc(sizeof(struct later));
 488             new->next = later_blocks;
 489             if (later_blocks && later_count < LATERBLOCKSIZE)
 490                 later_blocks->u[later_count].ptr = NULL;
 491             later_blocks = new;
 492             later_count = 0;
 493         }
 494
 495         if (count != 1)
 496             later_blocks->u[later_count++].count = count;
 497         later_blocks->u[later_count++].ptr = where;
 498     }
 499 }
 500
 501 static lispobj
 502 ptrans_boxed(lispobj thing, lispobj header, boolean constant)
 503 {
 504     long nwords;
 505     lispobj result, *new, *old;
 506
 507     nwords = CEILING(1 + HeaderValue(header), 2);
 508
 509     /* Allocate it */
 510     old = (lispobj *)native_pointer(thing);
 511     new = newspace_alloc(nwords,constant);
 512
 513     /* Copy it. */
 514     bcopy(old, new, nwords * sizeof(lispobj));
 515
 516     /* Deposit forwarding pointer. */
 517     result = make_lispobj(new, lowtag_of(thing));
 518     *old = result;
 519
 520     /* Scavenge it. */
 521     pscav(new, nwords, constant);
 522
 523     return result;
 524 }
 525
 526 /* We need to look at the layout to see whether it is a pure structure
 527  * class, and only then can we transport as constant. If it is pure,
 528  * we can ALWAYS transport as a constant. */
 529 static lispobj
 530 ptrans_instance(lispobj thing, lispobj header, boolean /* ignored */ constant)
 531 {
 532     struct layout *layout =
 533       (struct layout *) native_pointer(((struct instance *)native_pointer(thing))->slots[0]);
 534     lispobj pure = layout->pure;
 535
 536     switch (pure) {
 537     case T:
 538         return (ptrans_boxed(thing, header, 1));
 539     case NIL:
 540         return (ptrans_boxed(thing, header, 0));
 541     case 0:
 542         {
 543             /* Substructure: special case for the COMPACT-INFO-ENVs,
 544              * where the instance may have a point to the dynamic
 545              * space placed into it (e.g. the cache-name slot), but
 546              * the lists and arrays at the time of a purify can be
 547              * moved to the RO space. */
 548             long nwords;
 549             lispobj result, *new, *old;
 550
 551             nwords = CEILING(1 + HeaderValue(header), 2);
 552
 553             /* Allocate it */
 554             old = (lispobj *)native_pointer(thing);
 555             new = newspace_alloc(nwords, 0); /*  inconstant */
 556
 557             /* Copy it. */
 558             bcopy(old, new, nwords * sizeof(lispobj));
 559
 560             /* Deposit forwarding pointer. */
 561             result = make_lispobj(new, lowtag_of(thing));
 562             *old = result;
 563
 564             /* Scavenge it. */
 565             pscav(new, nwords, 1);
 566
 567             return result;
 568         }
 569     default:
 570         gc_abort();
 571         return NIL; /* dummy value: return something ... */
 572     }
 573 }
 574
 575 static lispobj
 576 ptrans_fdefn(lispobj thing, lispobj header)
 577 {
 578     long nwords;
 579     lispobj result, *new, *old, oldfn;
 580     struct fdefn *fdefn;
 581
 582     nwords = CEILING(1 + HeaderValue(header), 2);
 583
 584     /* Allocate it */
 585     old = (lispobj *)native_pointer(thing);
 586     new = newspace_alloc(nwords, 0);    /* inconstant */
 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     /* Scavenge the function. */
 596     fdefn = (struct fdefn *)new;
 597     oldfn = fdefn->fun;
 598     pscav(&fdefn->fun, 1, 0);
 599     if ((char *)oldfn + FUN_RAW_ADDR_OFFSET == fdefn->raw_addr)
 600         fdefn->raw_addr = (char *)fdefn->fun + FUN_RAW_ADDR_OFFSET;
 601
 602     return result;
 603 }
 604
 605 static lispobj
 606 ptrans_unboxed(lispobj thing, lispobj header)
 607 {
 608     long nwords;
 609     lispobj result, *new, *old;
 610
 611     nwords = CEILING(1 + HeaderValue(header), 2);
 612
 613     /* Allocate it */
 614     old = (lispobj *)native_pointer(thing);
 615     new = newspace_alloc(nwords,1);     /* always constant */
 616
 617     /* copy it. */
 618     bcopy(old, new, nwords * sizeof(lispobj));
 619
 620     /* Deposit forwarding pointer. */
 621     result = make_lispobj(new , lowtag_of(thing));
 622     *old = result;
 623
 624     return result;
 625 }
 626
 627 static lispobj
 628 ptrans_vector(lispobj thing, long bits, long extra,
 629               boolean boxed, boolean constant)
 630 {
 631     struct vector *vector;
 632     long nwords;
 633     lispobj result, *new;
 634     long length;
 635
 636     vector = (struct vector *)native_pointer(thing);
 637     length = fixnum_value(vector->length)+extra;
 638     // Argh, handle simple-vector-nil separately.
 639     if (bits == 0) {
 640       nwords = 2;
 641     } else {
 642       nwords = CEILING(NWORDS(length, bits) + 2, 2);
 643     }
 644
 645     new=newspace_alloc(nwords, (constant || !boxed));
 646     bcopy(vector, new, nwords * sizeof(lispobj));
 647
 648     result = make_lispobj(new, lowtag_of(thing));
 649     vector->header = result;
 650
 651     if (boxed)
 652         pscav(new, nwords, constant);
 653
 654     return result;
 655 }
 656
 657 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 658 static void
 659 apply_code_fixups_during_purify(struct code *old_code, struct code *new_code)
 660 {
 661     long nheader_words, ncode_words, nwords;
 662     void  *constants_start_addr, *constants_end_addr;
 663     void  *code_start_addr, *code_end_addr;
 664     lispobj fixups = NIL;
 665     unsigned  displacement = (unsigned)new_code - (unsigned)old_code;
 666     struct vector *fixups_vector;
 667
 668     ncode_words = fixnum_value(new_code->code_size);
 669     nheader_words = HeaderValue(*(lispobj *)new_code);
 670     nwords = ncode_words + nheader_words;
 671
 672     constants_start_addr = (void *)new_code + 5 * N_WORD_BYTES;
 673     constants_end_addr = (void *)new_code + nheader_words*N_WORD_BYTES;
 674     code_start_addr = (void *)new_code + nheader_words*N_WORD_BYTES;
 675     code_end_addr = (void *)new_code + nwords*N_WORD_BYTES;
 676
 677     /* The first constant should be a pointer to the fixups for this
 678      * code objects. Check. */
 679     fixups = new_code->constants[0];
 680
 681     /* It will be 0 or the unbound-marker if there are no fixups, and
 682      * will be an other-pointer to a vector if it is valid. */
 683     if ((fixups==0) ||
 684         (fixups==UNBOUND_MARKER_WIDETAG) ||
 685         !is_lisp_pointer(fixups)) {
 686 #ifdef LISP_FEATURE_GENCGC
 687         /* Check for a possible errors. */
 688         sniff_code_object(new_code,displacement);
 689 #endif
 690         return;
 691     }
 692
 693     fixups_vector = (struct vector *)native_pointer(fixups);
 694
 695     /* Could be pointing to a forwarding pointer. */
 696     if (is_lisp_pointer(fixups) && (dynamic_pointer_p(fixups))
 697         && forwarding_pointer_p(*(lispobj *)fixups_vector)) {
 698         /* If so then follow it. */
 699         fixups_vector =
 700             (struct vector *)native_pointer(*(lispobj *)fixups_vector);
 701     }
 702
 703     if (widetag_of(fixups_vector->header) == SIMPLE_ARRAY_WORD_WIDETAG) {
 704         /* We got the fixups for the code block. Now work through the
 705          * vector, and apply a fixup at each address. */
 706         long length = fixnum_value(fixups_vector->length);
 707         long i;
 708         for (i=0; i<length; i++) {
 709             unsigned offset = fixups_vector->data[i];
 710             /* Now check the current value of offset. */
 711             unsigned old_value =
 712                 *(unsigned *)((unsigned)code_start_addr + offset);
 713
 714             /* If it's within the old_code object then it must be an
 715              * absolute fixup (relative ones are not saved) */
 716             if ((old_value>=(unsigned)old_code)
 717                 && (old_value<((unsigned)old_code + nwords * N_WORD_BYTES)))
 718                 /* So add the dispacement. */
 719                 *(unsigned *)((unsigned)code_start_addr + offset) = old_value
 720                     + displacement;
 721             else
 722                 /* It is outside the old code object so it must be a relative
 723                  * fixup (absolute fixups are not saved). So subtract the
 724                  * displacement. */
 725                 *(unsigned *)((unsigned)code_start_addr + offset) = old_value
 726                     - displacement;
 727         }
 728     }
 729
 730     /* No longer need the fixups. */
 731     new_code->constants[0] = 0;
 732
 733 #ifdef LISP_FEATURE_GENCGC
 734     /* Check for possible errors. */
 735     sniff_code_object(new_code,displacement);
 736 #endif
 737 }
 738 #endif
 739
 740 static lispobj
 741 ptrans_code(lispobj thing)
 742 {
 743     struct code *code, *new;
 744     long nwords;
 745     lispobj func, result;
 746
 747     code = (struct code *)native_pointer(thing);
 748     nwords = CEILING(HeaderValue(code->header) + fixnum_value(code->code_size),
 749                      2);
 750
 751     new = (struct code *)newspace_alloc(nwords,1); /* constant */
 752
 753     bcopy(code, new, nwords * sizeof(lispobj));
 754
 755 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 756     apply_code_fixups_during_purify(code,new);
 757 #endif
 758
 759     result = make_lispobj(new, OTHER_POINTER_LOWTAG);
 760
 761     /* Stick in a forwarding pointer for the code object. */
 762     *(lispobj *)code = result;
 763
 764     /* Put in forwarding pointers for all the functions. */
 765     for (func = code->entry_points;
 766          func != NIL;
 767          func = ((struct simple_fun *)native_pointer(func))->next) {
 768
 769         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
 770
 771         *(lispobj *)native_pointer(func) = result + (func - thing);
 772     }
 773
 774     /* Arrange to scavenge the debug info later. */
 775     pscav_later(&new->debug_info, 1);
 776
 777     /* FIXME: why would this be a fixnum? */
 778     /* "why" is a hard word, but apparently for compiled functions the
 779        trace_table_offset contains the length of the instructions, as
 780        a fixnum.  See CODE-INST-AREA-LENGTH in
 781        src/compiler/target-disassem.lisp.  -- CSR, 2004-01-08 */
 782     if (!(fixnump(new->trace_table_offset)))
 783 #if 0
 784         pscav(&new->trace_table_offset, 1, 0);
 785 #else
 786         new->trace_table_offset = NIL; /* limit lifetime */
 787 #endif
 788
 789     /* Scavenge the constants. */
 790     pscav(new->constants, HeaderValue(new->header)-5, 1);
 791
 792     /* Scavenge all the functions. */
 793     pscav(&new->entry_points, 1, 1);
 794     for (func = new->entry_points;
 795          func != NIL;
 796          func = ((struct simple_fun *)native_pointer(func))->next) {
 797         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
 798         gc_assert(!dynamic_pointer_p(func));
 799
 800 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 801         /* Temporarily convert the self pointer to a real function pointer. */
 802         ((struct simple_fun *)native_pointer(func))->self
 803             -= FUN_RAW_ADDR_OFFSET;
 804 #endif
 805         pscav(&((struct simple_fun *)native_pointer(func))->self, 2, 1);
 806 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
 807         ((struct simple_fun *)native_pointer(func))->self
 808             += FUN_RAW_ADDR_OFFSET;
 809 #endif
 810         pscav_later(&((struct simple_fun *)native_pointer(func))->name, 3);
 811     }
 812
 813     return result;
 814 }
 815
 816 static lispobj
 817 ptrans_func(lispobj thing, lispobj header)
 818 {
 819     long nwords;
 820     lispobj code, *new, *old, result;
 821     struct simple_fun *function;
 822
 823     /* Thing can either be a function header, a closure function
 824      * header, a closure, or a funcallable-instance. If it's a closure
 825      * or a funcallable-instance, we do the same as ptrans_boxed.
 826      * Otherwise we have to do something strange, 'cause it is buried
 827      * inside a code object. */
 828
 829     if (widetag_of(header) == SIMPLE_FUN_HEADER_WIDETAG) {
 830
 831         /* We can only end up here if the code object has not been
 832          * scavenged, because if it had been scavenged, forwarding pointers
 833          * would have been left behind for all the entry points. */
 834
 835         function = (struct simple_fun *)native_pointer(thing);
 836         code =
 837             make_lispobj
 838             ((native_pointer(thing) -
 839               (HeaderValue(function->header))), OTHER_POINTER_LOWTAG);
 840
 841         /* This will cause the function's header to be replaced with a
 842          * forwarding pointer. */
 843
 844         ptrans_code(code);
 845
 846         /* So we can just return that. */
 847         return function->header;
 848     }
 849     else {
 850         /* It's some kind of closure-like thing. */
 851         nwords = CEILING(1 + HeaderValue(header), 2);
 852         old = (lispobj *)native_pointer(thing);
 853
 854         /* Allocate the new one.  FINs *must* not go in read_only
 855          * space.  Closures can; they never change */
 856
 857         new = newspace_alloc
 858             (nwords,(widetag_of(header)!=FUNCALLABLE_INSTANCE_HEADER_WIDETAG));
 859
 860         /* Copy it. */
 861         bcopy(old, new, nwords * sizeof(lispobj));
 862
 863         /* Deposit forwarding pointer. */
 864         result = make_lispobj(new, lowtag_of(thing));
 865         *old = result;
 866
 867         /* Scavenge it. */
 868         pscav(new, nwords, 0);
 869
 870         return result;
 871     }
 872 }
 873
 874 static lispobj
 875 ptrans_returnpc(lispobj thing, lispobj header)
 876 {
 877     lispobj code, new;
 878
 879     /* Find the corresponding code object. */
 880     code = thing - HeaderValue(header)*sizeof(lispobj);
 881
 882     /* Make sure it's been transported. */
 883     new = *(lispobj *)native_pointer(code);
 884     if (!forwarding_pointer_p(new))
 885         new = ptrans_code(code);
 886
 887     /* Maintain the offset: */
 888     return new + (thing - code);
 889 }
 890
 891 #define WORDS_PER_CONS CEILING(sizeof(struct cons) / sizeof(lispobj), 2)
 892
 893 static lispobj
 894 ptrans_list(lispobj thing, boolean constant)
 895 {
 896     struct cons *old, *new, *orig;
 897     long length;
 898
 899     orig = (struct cons *) newspace_alloc(0,constant);
 900     length = 0;
 901
 902     do {
 903         /* Allocate a new cons cell. */
 904         old = (struct cons *)native_pointer(thing);
 905         new = (struct cons *) newspace_alloc(WORDS_PER_CONS,constant);
 906
 907         /* Copy the cons cell and keep a pointer to the cdr. */
 908         new->car = old->car;
 909         thing = new->cdr = old->cdr;
 910
 911         /* Set up the forwarding pointer. */
 912         *(lispobj *)old = make_lispobj(new, LIST_POINTER_LOWTAG);
 913
 914         /* And count this cell. */
 915         length++;
 916     } while (lowtag_of(thing) == LIST_POINTER_LOWTAG &&
 917              dynamic_pointer_p(thing) &&
 918              !(forwarding_pointer_p(*(lispobj *)native_pointer(thing))));
 919
 920     /* Scavenge the list we just copied. */
 921     pscav((lispobj *)orig, length * WORDS_PER_CONS, constant);
 922
 923     return make_lispobj(orig, LIST_POINTER_LOWTAG);
 924 }
 925
 926 static lispobj
 927 ptrans_otherptr(lispobj thing, lispobj header, boolean constant)
 928 {
 929     switch (widetag_of(header)) {
 930         /* FIXME: this needs a reindent */
 931       case BIGNUM_WIDETAG:
 932       case SINGLE_FLOAT_WIDETAG:
 933       case DOUBLE_FLOAT_WIDETAG:
 934 #ifdef LONG_FLOAT_WIDETAG
 935       case LONG_FLOAT_WIDETAG:
 936 #endif
 937 #ifdef COMPLEX_SINGLE_FLOAT_WIDETAG
 938       case COMPLEX_SINGLE_FLOAT_WIDETAG:
 939 #endif
 940 #ifdef COMPLEX_DOUBLE_FLOAT_WIDETAG
 941       case COMPLEX_DOUBLE_FLOAT_WIDETAG:
 942 #endif
 943 #ifdef COMPLEX_LONG_FLOAT_WIDETAG
 944       case COMPLEX_LONG_FLOAT_WIDETAG:
 945 #endif
 946       case SAP_WIDETAG:
 947           return ptrans_unboxed(thing, header);
 948
 949       case RATIO_WIDETAG:
 950       case COMPLEX_WIDETAG:
 951       case SIMPLE_ARRAY_WIDETAG:
 952       case COMPLEX_BASE_STRING_WIDETAG:
 953 #ifdef COMPLEX_CHARACTER_STRING_WIDETAG
 954     case COMPLEX_CHARACTER_STRING_WIDETAG:
 955 #endif
 956       case COMPLEX_BIT_VECTOR_WIDETAG:
 957       case COMPLEX_VECTOR_NIL_WIDETAG:
 958       case COMPLEX_VECTOR_WIDETAG:
 959       case COMPLEX_ARRAY_WIDETAG:
 960         return ptrans_boxed(thing, header, constant);
 961
 962       case VALUE_CELL_HEADER_WIDETAG:
 963       case WEAK_POINTER_WIDETAG:
 964         return ptrans_boxed(thing, header, 0);
 965
 966       case SYMBOL_HEADER_WIDETAG:
 967         return ptrans_boxed(thing, header, 0);
 968
 969       case SIMPLE_ARRAY_NIL_WIDETAG:
 970         return ptrans_vector(thing, 0, 0, 0, constant);
 971
 972       case SIMPLE_BASE_STRING_WIDETAG:
 973         return ptrans_vector(thing, 8, 1, 0, constant);
 974
 975 #ifdef SIMPLE_CHARACTER_STRING_WIDETAG
 976     case SIMPLE_CHARACTER_STRING_WIDETAG:
 977         return ptrans_vector(thing, 32, 1, 0, constant);
 978 #endif
 979
 980       case SIMPLE_BIT_VECTOR_WIDETAG:
 981         return ptrans_vector(thing, 1, 0, 0, constant);
 982
 983       case SIMPLE_VECTOR_WIDETAG:
 984         return ptrans_vector(thing, N_WORD_BITS, 0, 1, constant);
 985
 986       case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
 987         return ptrans_vector(thing, 2, 0, 0, constant);
 988
 989       case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
 990         return ptrans_vector(thing, 4, 0, 0, constant);
 991
 992       case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
 993 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
 994       case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
 995       case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
 996 #endif
 997         return ptrans_vector(thing, 8, 0, 0, constant);
 998
 999       case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
1000 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
1001       case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
1002       case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
1003 #endif
1004         return ptrans_vector(thing, 16, 0, 0, constant);
1005
1006       case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
1007 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
1008       case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
1009       case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
1010 #endif
1011 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
1012       case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
1013       case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
1014 #endif
1015         return ptrans_vector(thing, 32, 0, 0, constant);
1016
1017 #if N_WORD_BITS == 64
1018 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_60_WIDETAG
1019       case SIMPLE_ARRAY_UNSIGNED_BYTE_60_WIDETAG:
1020 #endif
1021 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_63_WIDETAG
1022       case SIMPLE_ARRAY_UNSIGNED_BYTE_63_WIDETAG:
1023 #endif
1024 #ifdef SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG
1025       case SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG:
1026 #endif
1027 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG
1028       case SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG:
1029 #endif
1030 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG
1031       case SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG:
1032 #endif
1033         return ptrans_vector(thing, 64, 0, 0, constant);
1034 #endif
1035
1036       case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
1037         return ptrans_vector(thing, 32, 0, 0, constant);
1038
1039       case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
1040         return ptrans_vector(thing, 64, 0, 0, constant);
1041
1042 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
1043       case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
1044 #ifdef LISP_FEATURE_X86
1045         return ptrans_vector(thing, 96, 0, 0, constant);
1046 #endif
1047 #ifdef LISP_FEATURE_SPARC
1048         return ptrans_vector(thing, 128, 0, 0, constant);
1049 #endif
1050 #endif
1051
1052 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
1053       case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
1054         return ptrans_vector(thing, 64, 0, 0, constant);
1055 #endif
1056
1057 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
1058       case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
1059         return ptrans_vector(thing, 128, 0, 0, constant);
1060 #endif
1061
1062 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
1063       case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
1064 #ifdef LISP_FEATURE_X86
1065         return ptrans_vector(thing, 192, 0, 0, constant);
1066 #endif
1067 #ifdef LISP_FEATURE_SPARC
1068         return ptrans_vector(thing, 256, 0, 0, constant);
1069 #endif
1070 #endif
1071
1072       case CODE_HEADER_WIDETAG:
1073         return ptrans_code(thing);
1074
1075       case RETURN_PC_HEADER_WIDETAG:
1076         return ptrans_returnpc(thing, header);
1077
1078       case FDEFN_WIDETAG:
1079         return ptrans_fdefn(thing, header);
1080
1081       default:
1082         fprintf(stderr, "Invalid widetag: %d\n", widetag_of(header));
1083         /* Should only come across other pointers to the above stuff. */
1084         gc_abort();
1085         return NIL;
1086     }
1087 }
1088
1089 static long
1090 pscav_fdefn(struct fdefn *fdefn)
1091 {
1092     boolean fix_func;
1093
1094     fix_func = ((char *)(fdefn->fun+FUN_RAW_ADDR_OFFSET) == fdefn->raw_addr);
1095     pscav(&fdefn->name, 1, 1);
1096     pscav(&fdefn->fun, 1, 0);
1097     if (fix_func)
1098         fdefn->raw_addr = (char *)(fdefn->fun + FUN_RAW_ADDR_OFFSET);
1099     return sizeof(struct fdefn) / sizeof(lispobj);
1100 }
1101
1102 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
1103 /* now putting code objects in static space */
1104 static long
1105 pscav_code(struct code*code)
1106 {
1107     long nwords;
1108     lispobj func;
1109     nwords = CEILING(HeaderValue(code->header) + fixnum_value(code->code_size),
1110                      2);
1111
1112     /* Arrange to scavenge the debug info later. */
1113     pscav_later(&code->debug_info, 1);
1114
1115     /* Scavenge the constants. */
1116     pscav(code->constants, HeaderValue(code->header)-5, 1);
1117
1118     /* Scavenge all the functions. */
1119     pscav(&code->entry_points, 1, 1);
1120     for (func = code->entry_points;
1121          func != NIL;
1122          func = ((struct simple_fun *)native_pointer(func))->next) {
1123         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
1124         gc_assert(!dynamic_pointer_p(func));
1125
1126 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
1127         /* Temporarily convert the self pointer to a real function
1128          * pointer. */
1129         ((struct simple_fun *)native_pointer(func))->self
1130             -= FUN_RAW_ADDR_OFFSET;
1131 #endif
1132         pscav(&((struct simple_fun *)native_pointer(func))->self, 2, 1);
1133 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
1134         ((struct simple_fun *)native_pointer(func))->self
1135             += FUN_RAW_ADDR_OFFSET;
1136 #endif
1137         pscav_later(&((struct simple_fun *)native_pointer(func))->name, 3);
1138     }
1139
1140     return CEILING(nwords,2);
1141 }
1142 #endif
1143
1144 static lispobj *
1145 pscav(lispobj *addr, long nwords, boolean constant)
1146 {
1147     lispobj thing, *thingp, header;
1148     long count = 0; /* (0 = dummy init value to stop GCC warning) */
1149     struct vector *vector;
1150
1151     while (nwords > 0) {
1152         thing = *addr;
1153         if (is_lisp_pointer(thing)) {
1154             /* It's a pointer. Is it something we might have to move? */
1155             if (dynamic_pointer_p(thing)) {
1156                 /* Maybe. Have we already moved it? */
1157                 thingp = (lispobj *)native_pointer(thing);
1158                 header = *thingp;
1159                 if (is_lisp_pointer(header) && forwarding_pointer_p(header))
1160                     /* Yep, so just copy the forwarding pointer. */
1161                     thing = header;
1162                 else {
1163                     /* Nope, copy the object. */
1164                     switch (lowtag_of(thing)) {
1165                       case FUN_POINTER_LOWTAG:
1166                         thing = ptrans_func(thing, header);
1167                         break;
1168
1169                       case LIST_POINTER_LOWTAG:
1170                         thing = ptrans_list(thing, constant);
1171                         break;
1172
1173                       case INSTANCE_POINTER_LOWTAG:
1174                         thing = ptrans_instance(thing, header, constant);
1175                         break;
1176
1177                       case OTHER_POINTER_LOWTAG:
1178                         thing = ptrans_otherptr(thing, header, constant);
1179                         break;
1180
1181                       default:
1182                         /* It was a pointer, but not one of them? */
1183                         gc_abort();
1184                     }
1185                 }
1186                 *addr = thing;
1187             }
1188             count = 1;
1189         }
1190 #if N_WORD_BITS == 64
1191         else if (widetag_of(thing) == SINGLE_FLOAT_WIDETAG) {
1192             count = 1;
1193         }
1194 #endif
1195         else if (thing & FIXNUM_TAG_MASK) {
1196             /* It's an other immediate. Maybe the header for an unboxed */
1197             /* object. */
1198             switch (widetag_of(thing)) {
1199               case BIGNUM_WIDETAG:
1200               case SINGLE_FLOAT_WIDETAG:
1201               case DOUBLE_FLOAT_WIDETAG:
1202 #ifdef LONG_FLOAT_WIDETAG
1203               case LONG_FLOAT_WIDETAG:
1204 #endif
1205               case SAP_WIDETAG:
1206                 /* It's an unboxed simple object. */
1207                 count = CEILING(HeaderValue(thing)+1, 2);
1208                 break;
1209
1210               case SIMPLE_VECTOR_WIDETAG:
1211                   if (HeaderValue(thing) == subtype_VectorValidHashing) {
1212                     *addr = (subtype_VectorMustRehash << N_WIDETAG_BITS) |
1213                         SIMPLE_VECTOR_WIDETAG;
1214                   }
1215                 count = 2;
1216                 break;
1217
1218               case SIMPLE_ARRAY_NIL_WIDETAG:
1219                 count = 2;
1220                 break;
1221
1222               case SIMPLE_BASE_STRING_WIDETAG:
1223                 vector = (struct vector *)addr;
1224                 count = CEILING(NWORDS(fixnum_value(vector->length)+1,8)+2,2);
1225                 break;
1226
1227 #ifdef SIMPLE_CHARACTER_STRING_WIDETAG
1228             case SIMPLE_CHARACTER_STRING_WIDETAG:
1229                 vector = (struct vector *)addr;
1230                 count = CEILING(NWORDS(fixnum_value(vector->length)+1,32)+2,2);
1231                 break;
1232 #endif
1233
1234               case SIMPLE_BIT_VECTOR_WIDETAG:
1235                 vector = (struct vector *)addr;
1236                 count = CEILING(NWORDS(fixnum_value(vector->length),1)+2,2);
1237                 break;
1238
1239               case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
1240                 vector = (struct vector *)addr;
1241                 count = CEILING(NWORDS(fixnum_value(vector->length),2)+2,2);
1242                 break;
1243
1244               case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
1245                 vector = (struct vector *)addr;
1246                 count = CEILING(NWORDS(fixnum_value(vector->length),4)+2,2);
1247                 break;
1248
1249               case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
1250 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
1251               case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
1252               case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
1253 #endif
1254                 vector = (struct vector *)addr;
1255                 count = CEILING(NWORDS(fixnum_value(vector->length),8)+2,2);
1256                 break;
1257
1258               case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
1259 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
1260               case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
1261               case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
1262 #endif
1263                 vector = (struct vector *)addr;
1264                 count = CEILING(NWORDS(fixnum_value(vector->length),16)+2,2);
1265                 break;
1266
1267               case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
1268 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
1269               case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
1270               case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
1271 #endif
1272 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
1273               case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
1274               case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
1275 #endif
1276                 vector = (struct vector *)addr;
1277                 count = CEILING(NWORDS(fixnum_value(vector->length),32)+2,2);
1278                 break;
1279
1280 #if N_WORD_BITS == 64
1281               case SIMPLE_ARRAY_UNSIGNED_BYTE_64_WIDETAG:
1282 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG
1283               case SIMPLE_ARRAY_SIGNED_BYTE_61_WIDETAG:
1284               case SIMPLE_ARRAY_UNSIGNED_BYTE_60_WIDETAG:
1285 #endif
1286 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG
1287               case SIMPLE_ARRAY_SIGNED_BYTE_64_WIDETAG:
1288               case SIMPLE_ARRAY_UNSIGNED_BYTE_63_WIDETAG:
1289 #endif
1290                 vector = (struct vector *)addr;
1291                 count = CEILING(NWORDS(fixnum_value(vector->length),64)+2,2);
1292                 break;
1293 #endif
1294
1295               case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
1296                 vector = (struct vector *)addr;
1297                 count = CEILING(NWORDS(fixnum_value(vector->length), 32) + 2,
1298                                 2);
1299                 break;
1300
1301               case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
1302 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
1303               case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
1304 #endif
1305                 vector = (struct vector *)addr;
1306                 count = CEILING(NWORDS(fixnum_value(vector->length), 64) + 2,
1307                                 2);
1308                 break;
1309
1310 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
1311               case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
1312                 vector = (struct vector *)addr;
1313 #ifdef LISP_FEATURE_X86
1314                 count = fixnum_value(vector->length)*3+2;
1315 #endif
1316 #ifdef LISP_FEATURE_SPARC
1317                 count = fixnum_value(vector->length)*4+2;
1318 #endif
1319                 break;
1320 #endif
1321
1322 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
1323               case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
1324                 vector = (struct vector *)addr;
1325                 count = CEILING(NWORDS(fixnum_value(vector->length), 128) + 2,
1326                                 2);
1327                 break;
1328 #endif
1329
1330 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
1331               case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
1332                 vector = (struct vector *)addr;
1333 #ifdef LISP_FEATURE_X86
1334                 count = fixnum_value(vector->length)*6+2;
1335 #endif
1336 #ifdef LISP_FEATURE_SPARC
1337                 count = fixnum_value(vector->length)*8+2;
1338 #endif
1339                 break;
1340 #endif
1341
1342               case CODE_HEADER_WIDETAG:
1343 #if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
1344                 gc_abort(); /* no code headers in static space */
1345 #else
1346                 count = pscav_code((struct code*)addr);
1347 #endif
1348                 break;
1349
1350               case SIMPLE_FUN_HEADER_WIDETAG:
1351               case RETURN_PC_HEADER_WIDETAG:
1352                 /* We should never hit any of these, 'cause they occur
1353                  * buried in the middle of code objects. */
1354                 gc_abort();
1355                 break;
1356
1357 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
1358               case CLOSURE_HEADER_WIDETAG:
1359               case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
1360                 /* The function self pointer needs special care on the
1361                  * x86 because it is the real entry point. */
1362                 {
1363                   lispobj fun = ((struct closure *)addr)->fun
1364                     - FUN_RAW_ADDR_OFFSET;
1365                   pscav(&fun, 1, constant);
1366                   ((struct closure *)addr)->fun = fun + FUN_RAW_ADDR_OFFSET;
1367                 }
1368                 count = 2;
1369                 break;
1370 #endif
1371
1372               case WEAK_POINTER_WIDETAG:
1373                 /* Weak pointers get preserved during purify, 'cause I
1374                  * don't feel like figuring out how to break them. */
1375                 pscav(addr+1, 2, constant);
1376                 count = 4;
1377                 break;
1378
1379               case FDEFN_WIDETAG:
1380                 /* We have to handle fdefn objects specially, so we
1381                  * can fix up the raw function address. */
1382                 count = pscav_fdefn((struct fdefn *)addr);
1383                 break;
1384
1385               case INSTANCE_HEADER_WIDETAG:
1386                 {
1387                     struct instance *instance = (struct instance *) addr;
1388                     struct layout *layout
1389                         = (struct layout *) native_pointer(instance->slots[0]);
1390                     long nuntagged = fixnum_value(layout->n_untagged_slots);
1391                     long nslots = HeaderValue(*addr);
1392                     pscav(addr + 1, nslots - nuntagged, constant);
1393                     count = CEILING(1 + nslots, 2);
1394                 }
1395                 break;
1396
1397               default:
1398                 count = 1;
1399                 break;
1400             }
1401         }
1402         else {
1403             /* It's a fixnum. */
1404             count = 1;
1405         }
1406
1407         addr += count;
1408         nwords -= count;
1409     }
1410
1411     return addr;
1412 }
1413
1414 int
1415 purify(lispobj static_roots, lispobj read_only_roots)
1416 {
1417     lispobj *clean;
1418     long count, i;
1419     struct later *laters, *next;
1420     struct thread *thread;
1421
1422     if(all_threads->next) {
1423         /* FIXME: there should be _some_ sensible error reporting
1424          * convention.  See following comment too */
1425         fprintf(stderr,"Can't purify when more than one thread exists\n");
1426         fflush(stderr);
1427         return 0;
1428     }
1429
1430 #ifdef PRINTNOISE
1431     printf("[doing purification:");
1432     fflush(stdout);
1433 #endif
1434 #ifdef LISP_FEATURE_GENCGC
1435     gc_alloc_update_all_page_tables();
1436 #endif
1437     for_each_thread(thread)
1438         if (fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread)) != 0) {
1439         /* FIXME: 1. What does this mean? 2. It shouldn't be reporting
1440          * its error simply by a. printing a string b. to stdout instead
1441          * of stderr. */
1442         printf(" Ack! Can't purify interrupt contexts. ");
1443         fflush(stdout);
1444         return 0;
1445     }
1446
1447 #if defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64)
1448     dynamic_space_purify_pointer =
1449       (lispobj*)SymbolValue(ALLOCATION_POINTER,0);
1450 #else
1451 #if defined(LISP_FEATURE_GENCGC)
1452     dynamic_space_purify_pointer = get_alloc_pointer();
1453 #else
1454     dynamic_space_purify_pointer = dynamic_space_free_pointer;
1455 #endif
1456 #endif
1457
1458     read_only_end = read_only_free =
1459         (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER,0);
1460     static_end = static_free =
1461         (lispobj *)SymbolValue(STATIC_SPACE_FREE_POINTER,0);
1462
1463 #ifdef PRINTNOISE
1464     printf(" roots");
1465     fflush(stdout);
1466 #endif
1467
1468 #if defined(LISP_FEATURE_GENCGC) && (defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64))
1469     /* note this expects only one thread to be active.  We'd have to
1470      * stop all the others in the same way as GC does if we wanted
1471      * PURIFY to work when >1 thread exists */
1472     setup_i386_stack_scav(((&static_roots)-2),
1473                           ((void *)all_threads->control_stack_end));
1474 #endif
1475
1476     pscav(&static_roots, 1, 0);
1477     pscav(&read_only_roots, 1, 1);
1478
1479 #ifdef PRINTNOISE
1480     printf(" handlers");
1481     fflush(stdout);
1482 #endif
1483     pscav((lispobj *) interrupt_handlers,
1484           sizeof(interrupt_handlers) / sizeof(lispobj),
1485           0);
1486
1487 #ifdef PRINTNOISE
1488     printf(" stack");
1489     fflush(stdout);
1490 #endif
1491 #if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
1492     pscav((lispobj *)all_threads->control_stack_start,
1493           current_control_stack_pointer -
1494           all_threads->control_stack_start,
1495           0);
1496 #else
1497 #ifdef LISP_FEATURE_GENCGC
1498     pscav_i386_stack();
1499 #endif
1500 #endif
1501
1502 #ifdef PRINTNOISE
1503     printf(" bindings");
1504     fflush(stdout);
1505 #endif
1506 #if !(defined(LISP_FEATURE_X86) || defined(LISP_FEATURE_X86_64))
1507     pscav( (lispobj *)all_threads->binding_stack_start,
1508           (lispobj *)current_binding_stack_pointer -
1509            all_threads->binding_stack_start,
1510           0);
1511 #else
1512     for_each_thread(thread) {
1513         pscav( (lispobj *)thread->binding_stack_start,
1514                (lispobj *)SymbolValue(BINDING_STACK_POINTER,thread) -
1515                (lispobj *)thread->binding_stack_start,
1516           0);
1517 #ifdef LISP_FEATURE_SB_THREAD
1518         pscav( (lispobj *) (thread+1),
1519                fixnum_value(SymbolValue(FREE_TLS_INDEX,0)) -
1520                (sizeof (struct thread))/(sizeof (lispobj)),
1521           0);
1522 #endif
1523     }
1524
1525
1526 #endif
1527
1528     /* The original CMU CL code had scavenge-read-only-space code
1529      * controlled by the Lisp-level variable
1530      * *SCAVENGE-READ-ONLY-SPACE*. It was disabled by default, and it
1531      * wasn't documented under what circumstances it was useful or
1532      * safe to turn it on, so it's been turned off in SBCL. If you
1533      * want/need this functionality, and can test and document it,
1534      * please submit a patch. */
1535 #if 0
1536     if (SymbolValue(SCAVENGE_READ_ONLY_SPACE) != UNBOUND_MARKER_WIDETAG
1537         && SymbolValue(SCAVENGE_READ_ONLY_SPACE) != NIL) {
1538       unsigned  read_only_space_size =
1539           (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER) -
1540           (lispobj *)READ_ONLY_SPACE_START;
1541       fprintf(stderr,
1542               "scavenging read only space: %d bytes\n",
1543               read_only_space_size * sizeof(lispobj));
1544       pscav( (lispobj *)READ_ONLY_SPACE_START, read_only_space_size, 0);
1545     }
1546 #endif
1547
1548 #ifdef PRINTNOISE
1549     printf(" static");
1550     fflush(stdout);
1551 #endif
1552     clean = (lispobj *)STATIC_SPACE_START;
1553     do {
1554         while (clean != static_free)
1555             clean = pscav(clean, static_free - clean, 0);
1556         laters = later_blocks;
1557         count = later_count;
1558         later_blocks = NULL;
1559         later_count = 0;
1560         while (laters != NULL) {
1561             for (i = 0; i < count; i++) {
1562                 if (laters->u[i].count == 0) {
1563                     ;
1564                 } else if (laters->u[i].count <= LATERMAXCOUNT) {
1565                     pscav(laters->u[i+1].ptr, laters->u[i].count, 1);
1566                     i++;
1567                 } else {
1568                     pscav(laters->u[i].ptr, 1, 1);
1569                 }
1570             }
1571             next = laters->next;
1572             free(laters);
1573             laters = next;
1574             count = LATERBLOCKSIZE;
1575         }
1576     } while (clean != static_free || later_blocks != NULL);
1577
1578 #ifdef PRINTNOISE
1579     printf(" cleanup");
1580     fflush(stdout);
1581 #endif
1582
1583     os_zero((os_vm_address_t) current_dynamic_space,
1584             (os_vm_size_t) DYNAMIC_SPACE_SIZE);
1585
1586     /* Zero the stack. Note that the stack is also zeroed by SUB-GC
1587      * calling SCRUB-CONTROL-STACK - this zeros the stack on the x86. */
1588 #if !defined(LISP_FEATURE_X86) && !defined(LISP_FEATURE_X86_64)
1589     os_zero((os_vm_address_t) current_control_stack_pointer,
1590             (os_vm_size_t)
1591             ((all_threads->control_stack_end -
1592               current_control_stack_pointer) * sizeof(lispobj)));
1593 #endif
1594
1595     /* It helps to update the heap free pointers so that free_heap can
1596      * verify after it's done. */
1597     SetSymbolValue(READ_ONLY_SPACE_FREE_POINTER, (lispobj)read_only_free,0);
1598     SetSymbolValue(STATIC_SPACE_FREE_POINTER, (lispobj)static_free,0);
1599
1600 #if defined LISP_FEATURE_GENCGC
1601     gc_free_heap();
1602 #else
1603     dynamic_space_free_pointer = current_dynamic_space;
1604     set_auto_gc_trigger(bytes_consed_between_gcs);
1605 #endif
1606
1607     /* Blast away instruction cache */
1608     os_flush_icache((os_vm_address_t)READ_ONLY_SPACE_START, READ_ONLY_SPACE_SIZE);
1609     os_flush_icache((os_vm_address_t)STATIC_SPACE_START, STATIC_SPACE_SIZE);
1610
1611 #ifdef PRINTNOISE
1612     printf(" done]\n");
1613     fflush(stdout);
1614 #endif
1615     return 0;
1616 }