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 "runtime.h"
  23 #include "os.h"
  24 #include "sbcl.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_X86)
  39 /* again, what's so special about the x86 that this is differently
  40  * visible there than on other platforms? -dan 20010125
  41  */
  42 static lispobj *dynamic_space_free_pointer;
  43 #endif
  44 extern unsigned long bytes_consed_between_gcs;
  45
  46 #define gc_abort() \
  47   lose("GC invariant lost, file \"%s\", line %d", __FILE__, __LINE__)
  48
  49 #if 1
  50 #define gc_assert(ex) do { \
  51         if (!(ex)) gc_abort(); \
  52 } while (0)
  53 #else
  54 #define gc_assert(ex)
  55 #endif
  56
  57 \f
  58 /* These hold the original end of the read_only and static spaces so
  59  * we can tell what are forwarding pointers. */
  60
  61 static lispobj *read_only_end, *static_end;
  62
  63 static lispobj *read_only_free, *static_free;
  64
  65 static lispobj *pscav(lispobj *addr, int nwords, boolean constant);
  66
  67 #define LATERBLOCKSIZE 1020
  68 #define LATERMAXCOUNT 10
  69
  70 static struct
  71 later {
  72     struct later *next;
  73     union {
  74         lispobj *ptr;
  75         int count;
  76     } u[LATERBLOCKSIZE];
  77 } *later_blocks = NULL;
  78 static int later_count = 0;
  79
  80 #define CEILING(x,y) (((x) + ((y) - 1)) & (~((y) - 1)))
  81 #define NWORDS(x,y) (CEILING((x),(y)) / (y))
  82
  83 /* FIXME: Shouldn't this be defined in sbcl.h?  See also notes in
  84  * cheneygc.c */
  85
  86 #ifdef sparc
  87 #define FUN_RAW_ADDR_OFFSET 0
  88 #else
  89 #define FUN_RAW_ADDR_OFFSET (6*sizeof(lispobj) - FUN_POINTER_LOWTAG)
  90 #endif
  91 \f
  92 static boolean
  93 forwarding_pointer_p(lispobj obj)
  94 {
  95     lispobj *ptr = native_pointer(obj);
  96
  97     return ((static_end <= ptr && ptr <= static_free) ||
  98             (read_only_end <= ptr && ptr <= read_only_free));
  99 }
 100
 101 static boolean
 102 dynamic_pointer_p(lispobj ptr)
 103 {
 104 #ifndef LISP_FEATURE_GENCGC
 105     return (ptr >= (lispobj)current_dynamic_space
 106             &&
 107             ptr < (lispobj)dynamic_space_free_pointer);
 108 #else
 109     /* Be more conservative, and remember, this is a maybe. */
 110     return (ptr >= (lispobj)DYNAMIC_SPACE_START
 111             &&
 112             ptr < (lispobj)dynamic_space_free_pointer);
 113 #endif
 114 }
 115
 116 static inline newspace_alloc(int nwords, int constantp)
 117 {
 118     lispobj *ret;
 119     nwords=CEILING(nwords,2);
 120     if(constantp) {
 121         ret=read_only_free;
 122         read_only_free+=nwords;
 123     } else {
 124         ret=static_free;
 125         static_free+=nwords;
 126     }
 127     return ret;
 128 }
 129
 130
 131 \f
 132 #ifdef LISP_FEATURE_X86
 133
 134 #ifdef LISP_FEATURE_GENCGC
 135 /*
 136  * enhanced x86/GENCGC stack scavenging by Douglas Crosher
 137  *
 138  * Scavenging the stack on the i386 is problematic due to conservative
 139  * roots and raw return addresses. Here it is handled in two passes:
 140  * the first pass runs before any objects are moved and tries to
 141  * identify valid pointers and return address on the stack, the second
 142  * pass scavenges these.
 143  */
 144
 145 static unsigned pointer_filter_verbose = 0;
 146
 147 /* FIXME: This is substantially the same code as
 148  * possibly_valid_dynamic_space_pointer in gencgc.c.  The only
 149  * relevant difference seems to be that the gencgc code also checks
 150  * for raw pointers into Code objects, whereas in purify these are
 151  * checked separately in setup_i386_stack_scav - they go onto
 152  * valid_stack_ra_locations instead of just valid_stack_locations */
 153
 154 static int
 155 valid_dynamic_space_pointer(lispobj *pointer, lispobj *start_addr)
 156 {
 157     /* If it's not a return address then it needs to be a valid Lisp
 158      * pointer. */
 159     if (!is_lisp_pointer((lispobj)pointer))
 160         return 0;
 161
 162     /* Check that the object pointed to is consistent with the pointer
 163      * low tag. */
 164     switch (lowtag_of((lispobj)pointer)) {
 165     case FUN_POINTER_LOWTAG:
 166         /* Start_addr should be the enclosing code object, or a closure
 167          * header. */
 168         switch (widetag_of(*start_addr)) {
 169         case CODE_HEADER_WIDETAG:
 170             /* This case is probably caught above. */
 171             break;
 172         case CLOSURE_HEADER_WIDETAG:
 173         case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
 174             if ((int)pointer != ((int)start_addr+FUN_POINTER_LOWTAG)) {
 175                 if (pointer_filter_verbose) {
 176                     fprintf(stderr,"*Wf2: %x %x %x\n", (unsigned int) pointer,
 177                             (unsigned int) start_addr, *start_addr);
 178                 }
 179                 return 0;
 180             }
 181             break;
 182         default:
 183             if (pointer_filter_verbose) {
 184                 fprintf(stderr,"*Wf3: %x %x %x\n", (unsigned int) pointer,
 185                         (unsigned int) start_addr, *start_addr);
 186             }
 187             return 0;
 188         }
 189         break;
 190     case LIST_POINTER_LOWTAG:
 191         if ((int)pointer != ((int)start_addr+LIST_POINTER_LOWTAG)) {
 192             if (pointer_filter_verbose)
 193                 fprintf(stderr,"*Wl1: %x %x %x\n", (unsigned int) pointer,
 194                         (unsigned int) start_addr, *start_addr);
 195             return 0;
 196         }
 197         /* Is it plausible cons? */
 198         if ((is_lisp_pointer(start_addr[0])
 199             || ((start_addr[0] & 3) == 0) /* fixnum */
 200             || (widetag_of(start_addr[0]) == BASE_CHAR_WIDETAG)
 201             || (widetag_of(start_addr[0]) == UNBOUND_MARKER_WIDETAG))
 202            && (is_lisp_pointer(start_addr[1])
 203                || ((start_addr[1] & 3) == 0) /* fixnum */
 204                || (widetag_of(start_addr[1]) == BASE_CHAR_WIDETAG)
 205                || (widetag_of(start_addr[1]) == UNBOUND_MARKER_WIDETAG))) {
 206             break;
 207         } else {
 208             if (pointer_filter_verbose) {
 209                 fprintf(stderr,"*Wl2: %x %x %x\n", (unsigned int) pointer,
 210                         (unsigned int) start_addr, *start_addr);
 211             }
 212             return 0;
 213         }
 214     case INSTANCE_POINTER_LOWTAG:
 215         if ((int)pointer != ((int)start_addr+INSTANCE_POINTER_LOWTAG)) {
 216             if (pointer_filter_verbose) {
 217                 fprintf(stderr,"*Wi1: %x %x %x\n", (unsigned int) pointer,
 218                         (unsigned int) start_addr, *start_addr);
 219             }
 220             return 0;
 221         }
 222         if (widetag_of(start_addr[0]) != INSTANCE_HEADER_WIDETAG) {
 223             if (pointer_filter_verbose) {
 224                 fprintf(stderr,"*Wi2: %x %x %x\n", (unsigned int) pointer,
 225                         (unsigned int) start_addr, *start_addr);
 226             }
 227             return 0;
 228         }
 229         break;
 230     case OTHER_POINTER_LOWTAG:
 231         if ((int)pointer != ((int)start_addr+OTHER_POINTER_LOWTAG)) {
 232             if (pointer_filter_verbose) {
 233                 fprintf(stderr,"*Wo1: %x %x %x\n", (unsigned int) pointer,
 234                         (unsigned int) start_addr, *start_addr);
 235             }
 236             return 0;
 237         }
 238         /* Is it plausible? Not a cons. XXX should check the headers. */
 239         if (is_lisp_pointer(start_addr[0]) || ((start_addr[0] & 3) == 0)) {
 240             if (pointer_filter_verbose) {
 241                 fprintf(stderr,"*Wo2: %x %x %x\n", (unsigned int) pointer,
 242                         (unsigned int) start_addr, *start_addr);
 243             }
 244             return 0;
 245         }
 246         switch (widetag_of(start_addr[0])) {
 247         case UNBOUND_MARKER_WIDETAG:
 248         case BASE_CHAR_WIDETAG:
 249             if (pointer_filter_verbose) {
 250                 fprintf(stderr,"*Wo3: %x %x %x\n", (unsigned int) pointer,
 251                         (unsigned int) start_addr, *start_addr);
 252             }
 253             return 0;
 254
 255             /* only pointed to by function pointers? */
 256         case CLOSURE_HEADER_WIDETAG:
 257         case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
 258             if (pointer_filter_verbose) {
 259                 fprintf(stderr,"*Wo4: %x %x %x\n", (unsigned int) pointer,
 260                         (unsigned int) start_addr, *start_addr);
 261             }
 262             return 0;
 263
 264         case INSTANCE_HEADER_WIDETAG:
 265             if (pointer_filter_verbose) {
 266                 fprintf(stderr,"*Wo5: %x %x %x\n", (unsigned int) pointer,
 267                         (unsigned int) start_addr, *start_addr);
 268             }
 269             return 0;
 270
 271             /* the valid other immediate pointer objects */
 272         case SIMPLE_VECTOR_WIDETAG:
 273         case RATIO_WIDETAG:
 274         case COMPLEX_WIDETAG:
 275 #ifdef COMPLEX_SINGLE_FLOAT_WIDETAG
 276         case COMPLEX_SINGLE_FLOAT_WIDETAG:
 277 #endif
 278 #ifdef COMPLEX_DOUBLE_FLOAT_WIDETAG
 279         case COMPLEX_DOUBLE_FLOAT_WIDETAG:
 280 #endif
 281 #ifdef COMPLEX_LONG_FLOAT_WIDETAG
 282         case COMPLEX_LONG_FLOAT_WIDETAG:
 283 #endif
 284         case SIMPLE_ARRAY_WIDETAG:
 285         case COMPLEX_BASE_STRING_WIDETAG:
 286         case COMPLEX_VECTOR_NIL_WIDETAG:
 287         case COMPLEX_BIT_VECTOR_WIDETAG:
 288         case COMPLEX_VECTOR_WIDETAG:
 289         case COMPLEX_ARRAY_WIDETAG:
 290         case VALUE_CELL_HEADER_WIDETAG:
 291         case SYMBOL_HEADER_WIDETAG:
 292         case FDEFN_WIDETAG:
 293         case CODE_HEADER_WIDETAG:
 294         case BIGNUM_WIDETAG:
 295         case SINGLE_FLOAT_WIDETAG:
 296         case DOUBLE_FLOAT_WIDETAG:
 297 #ifdef LONG_FLOAT_WIDETAG
 298         case LONG_FLOAT_WIDETAG:
 299 #endif
 300         case SIMPLE_ARRAY_NIL_WIDETAG:
 301         case SIMPLE_BASE_STRING_WIDETAG:
 302         case SIMPLE_BIT_VECTOR_WIDETAG:
 303         case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
 304         case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
 305         case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
 306         case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
 307         case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
 308         case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
 309         case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
 310         case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
 311         case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
 312 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
 313         case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
 314 #endif
 315 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
 316         case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
 317 #endif
 318 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
 319         case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
 320 #endif
 321 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
 322         case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
 323 #endif
 324         case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
 325         case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
 326 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
 327         case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
 328 #endif
 329 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
 330         case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
 331 #endif
 332 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
 333         case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
 334 #endif
 335 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
 336         case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
 337 #endif
 338         case SAP_WIDETAG:
 339         case WEAK_POINTER_WIDETAG:
 340             break;
 341
 342         default:
 343             if (pointer_filter_verbose) {
 344                 fprintf(stderr,"*Wo6: %x %x %x\n", (unsigned int) pointer,
 345                         (unsigned int) start_addr, *start_addr);
 346             }
 347             return 0;
 348         }
 349         break;
 350     default:
 351         if (pointer_filter_verbose) {
 352             fprintf(stderr,"*W?: %x %x %x\n", (unsigned int) pointer,
 353                     (unsigned int) start_addr, *start_addr);
 354         }
 355         return 0;
 356     }
 357
 358     /* looks good */
 359     return 1;
 360 }
 361
 362 #define MAX_STACK_POINTERS 256
 363 lispobj *valid_stack_locations[MAX_STACK_POINTERS];
 364 unsigned int num_valid_stack_locations;
 365
 366 #define MAX_STACK_RETURN_ADDRESSES 128
 367 lispobj *valid_stack_ra_locations[MAX_STACK_RETURN_ADDRESSES];
 368 lispobj *valid_stack_ra_code_objects[MAX_STACK_RETURN_ADDRESSES];
 369 unsigned int num_valid_stack_ra_locations;
 370
 371 /* Identify valid stack slots. */
 372 static void
 373 setup_i386_stack_scav(lispobj *lowaddr, lispobj *base)
 374 {
 375     lispobj *sp = lowaddr;
 376     num_valid_stack_locations = 0;
 377     num_valid_stack_ra_locations = 0;
 378     for (sp = lowaddr; sp < base; sp++) {
 379         lispobj thing = *sp;
 380         /* Find the object start address */
 381         lispobj *start_addr = search_dynamic_space((void *)thing);
 382         if (start_addr) {
 383             /* We need to allow raw pointers into Code objects for
 384              * return addresses. This will also pick up pointers to
 385              * functions in code objects. */
 386             if (widetag_of(*start_addr) == CODE_HEADER_WIDETAG) {
 387                 /* FIXME asserting here is a really dumb thing to do.
 388                  * If we've overflowed some arbitrary static limit, we
 389                  * should just refuse to purify, instead of killing
 390                  * the whole lisp session
 391                  */
 392                 gc_assert(num_valid_stack_ra_locations <
 393                           MAX_STACK_RETURN_ADDRESSES);
 394                 valid_stack_ra_locations[num_valid_stack_ra_locations] = sp;
 395                 valid_stack_ra_code_objects[num_valid_stack_ra_locations++] =
 396                     (lispobj *)((int)start_addr + OTHER_POINTER_LOWTAG);
 397             } else {
 398                 if (valid_dynamic_space_pointer((void *)thing, start_addr)) {
 399                     gc_assert(num_valid_stack_locations < MAX_STACK_POINTERS);
 400                     valid_stack_locations[num_valid_stack_locations++] = sp;
 401                 }
 402             }
 403         }
 404     }
 405     if (pointer_filter_verbose) {
 406         fprintf(stderr, "number of valid stack pointers = %d\n",
 407                 num_valid_stack_locations);
 408         fprintf(stderr, "number of stack return addresses = %d\n",
 409                 num_valid_stack_ra_locations);
 410     }
 411 }
 412
 413 static void
 414 pscav_i386_stack(void)
 415 {
 416     int i;
 417
 418     for (i = 0; i < num_valid_stack_locations; i++)
 419         pscav(valid_stack_locations[i], 1, 0);
 420
 421     for (i = 0; i < num_valid_stack_ra_locations; i++) {
 422         lispobj code_obj = (lispobj)valid_stack_ra_code_objects[i];
 423         pscav(&code_obj, 1, 0);
 424         if (pointer_filter_verbose) {
 425             fprintf(stderr,"*C moved RA %x to %x; for code object %x to %x\n",
 426                     *valid_stack_ra_locations[i],
 427                     (int)(*valid_stack_ra_locations[i])
 428                     - ((int)valid_stack_ra_code_objects[i] - (int)code_obj),
 429                     (unsigned int) valid_stack_ra_code_objects[i], code_obj);
 430         }
 431         *valid_stack_ra_locations[i] =
 432             ((int)(*valid_stack_ra_locations[i])
 433              - ((int)valid_stack_ra_code_objects[i] - (int)code_obj));
 434     }
 435 }
 436 #endif
 437 #endif
 438
 439 \f
 440 static void
 441 pscav_later(lispobj *where, int count)
 442 {
 443     struct later *new;
 444
 445     if (count > LATERMAXCOUNT) {
 446         while (count > LATERMAXCOUNT) {
 447             pscav_later(where, LATERMAXCOUNT);
 448             count -= LATERMAXCOUNT;
 449             where += LATERMAXCOUNT;
 450         }
 451     }
 452     else {
 453         if (later_blocks == NULL || later_count == LATERBLOCKSIZE ||
 454             (later_count == LATERBLOCKSIZE-1 && count > 1)) {
 455             new  = (struct later *)malloc(sizeof(struct later));
 456             new->next = later_blocks;
 457             if (later_blocks && later_count < LATERBLOCKSIZE)
 458                 later_blocks->u[later_count].ptr = NULL;
 459             later_blocks = new;
 460             later_count = 0;
 461         }
 462
 463         if (count != 1)
 464             later_blocks->u[later_count++].count = count;
 465         later_blocks->u[later_count++].ptr = where;
 466     }
 467 }
 468
 469 static lispobj
 470 ptrans_boxed(lispobj thing, lispobj header, boolean constant)
 471 {
 472     int nwords;
 473     lispobj result, *new, *old;
 474
 475     nwords = 1 + HeaderValue(header);
 476
 477     /* Allocate it */
 478     old = (lispobj *)native_pointer(thing);
 479     new = newspace_alloc(nwords,constant);
 480
 481     /* Copy it. */
 482     bcopy(old, new, nwords * sizeof(lispobj));
 483
 484     /* Deposit forwarding pointer. */
 485     result = make_lispobj(new, lowtag_of(thing));
 486     *old = result;
 487
 488     /* Scavenge it. */
 489     pscav(new, nwords, constant);
 490
 491     return result;
 492 }
 493
 494 /* We need to look at the layout to see whether it is a pure structure
 495  * class, and only then can we transport as constant. If it is pure,
 496  * we can ALWAYS transport as a constant. */
 497 static lispobj
 498 ptrans_instance(lispobj thing, lispobj header, boolean /* ignored */ constant)
 499 {
 500     lispobj layout = ((struct instance *)native_pointer(thing))->slots[0];
 501     lispobj pure = ((struct instance *)native_pointer(layout))->slots[15];
 502
 503     switch (pure) {
 504     case T:
 505         return (ptrans_boxed(thing, header, 1));
 506     case NIL:
 507         return (ptrans_boxed(thing, header, 0));
 508     case 0:
 509         {
 510             /* Substructure: special case for the COMPACT-INFO-ENVs,
 511              * where the instance may have a point to the dynamic
 512              * space placed into it (e.g. the cache-name slot), but
 513              * the lists and arrays at the time of a purify can be
 514              * moved to the RO space. */
 515             int nwords;
 516             lispobj result, *new, *old;
 517
 518             nwords = 1 + HeaderValue(header);
 519
 520             /* Allocate it */
 521             old = (lispobj *)native_pointer(thing);
 522             new = newspace_alloc(nwords, 0); /*  inconstant */
 523
 524             /* Copy it. */
 525             bcopy(old, new, nwords * sizeof(lispobj));
 526
 527             /* Deposit forwarding pointer. */
 528             result = make_lispobj(new, lowtag_of(thing));
 529             *old = result;
 530
 531             /* Scavenge it. */
 532             pscav(new, nwords, 1);
 533
 534             return result;
 535         }
 536     default:
 537         gc_abort();
 538         return NIL; /* dummy value: return something ... */
 539     }
 540 }
 541
 542 static lispobj
 543 ptrans_fdefn(lispobj thing, lispobj header)
 544 {
 545     int nwords;
 546     lispobj result, *new, *old, oldfn;
 547     struct fdefn *fdefn;
 548
 549     nwords = 1 + HeaderValue(header);
 550
 551     /* Allocate it */
 552     old = (lispobj *)native_pointer(thing);
 553     new = newspace_alloc(nwords, 0);    /* inconstant */
 554
 555     /* Copy it. */
 556     bcopy(old, new, nwords * sizeof(lispobj));
 557
 558     /* Deposit forwarding pointer. */
 559     result = make_lispobj(new, lowtag_of(thing));
 560     *old = result;
 561
 562     /* Scavenge the function. */
 563     fdefn = (struct fdefn *)new;
 564     oldfn = fdefn->fun;
 565     pscav(&fdefn->fun, 1, 0);
 566     if ((char *)oldfn + FUN_RAW_ADDR_OFFSET == fdefn->raw_addr)
 567         fdefn->raw_addr = (char *)fdefn->fun + FUN_RAW_ADDR_OFFSET;
 568
 569     return result;
 570 }
 571
 572 static lispobj
 573 ptrans_unboxed(lispobj thing, lispobj header)
 574 {
 575     int nwords;
 576     lispobj result, *new, *old;
 577
 578     nwords = 1 + HeaderValue(header);
 579
 580     /* Allocate it */
 581     old = (lispobj *)native_pointer(thing);
 582     new = newspace_alloc(nwords,1);     /* always constant */
 583
 584     /* copy it. */
 585     bcopy(old, new, nwords * sizeof(lispobj));
 586
 587     /* Deposit forwarding pointer. */
 588     result = make_lispobj(new , lowtag_of(thing));
 589     *old = result;
 590
 591     return result;
 592 }
 593
 594 static lispobj
 595 ptrans_vector(lispobj thing, int bits, int extra,
 596               boolean boxed, boolean constant)
 597 {
 598     struct vector *vector;
 599     int nwords;
 600     lispobj result, *new;
 601
 602     vector = (struct vector *)native_pointer(thing);
 603     nwords = 2 + (CEILING((fixnum_value(vector->length)+extra)*bits,32)>>5);
 604
 605     new=newspace_alloc(nwords, (constant || !boxed));
 606     bcopy(vector, new, nwords * sizeof(lispobj));
 607
 608     result = make_lispobj(new, lowtag_of(thing));
 609     vector->header = result;
 610
 611     if (boxed)
 612         pscav(new, nwords, constant);
 613
 614     return result;
 615 }
 616
 617 #ifdef LISP_FEATURE_X86
 618 static void
 619 apply_code_fixups_during_purify(struct code *old_code, struct code *new_code)
 620 {
 621     int nheader_words, ncode_words, nwords;
 622     void  *constants_start_addr, *constants_end_addr;
 623     void  *code_start_addr, *code_end_addr;
 624     lispobj fixups = NIL;
 625     unsigned  displacement = (unsigned)new_code - (unsigned)old_code;
 626     struct vector *fixups_vector;
 627
 628     ncode_words = fixnum_value(new_code->code_size);
 629     nheader_words = HeaderValue(*(lispobj *)new_code);
 630     nwords = ncode_words + nheader_words;
 631
 632     constants_start_addr = (void *)new_code + 5*4;
 633     constants_end_addr = (void *)new_code + nheader_words*4;
 634     code_start_addr = (void *)new_code + nheader_words*4;
 635     code_end_addr = (void *)new_code + nwords*4;
 636
 637     /* The first constant should be a pointer to the fixups for this
 638      * code objects. Check. */
 639     fixups = new_code->constants[0];
 640
 641     /* It will be 0 or the unbound-marker if there are no fixups, and
 642      * will be an other-pointer to a vector if it is valid. */
 643     if ((fixups==0) ||
 644         (fixups==UNBOUND_MARKER_WIDETAG) ||
 645         !is_lisp_pointer(fixups)) {
 646 #ifdef LISP_FEATURE_GENCGC
 647         /* Check for a possible errors. */
 648         sniff_code_object(new_code,displacement);
 649 #endif
 650         return;
 651     }
 652
 653     fixups_vector = (struct vector *)native_pointer(fixups);
 654
 655     /* Could be pointing to a forwarding pointer. */
 656     if (is_lisp_pointer(fixups) && (dynamic_pointer_p(fixups))
 657         && forwarding_pointer_p(*(lispobj *)fixups_vector)) {
 658         /* If so then follow it. */
 659         fixups_vector =
 660             (struct vector *)native_pointer(*(lispobj *)fixups_vector);
 661     }
 662
 663     if (widetag_of(fixups_vector->header) ==
 664         SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG) {
 665         /* We got the fixups for the code block. Now work through the
 666          * vector, and apply a fixup at each address. */
 667         int length = fixnum_value(fixups_vector->length);
 668         int i;
 669         for (i=0; i<length; i++) {
 670             unsigned offset = fixups_vector->data[i];
 671             /* Now check the current value of offset. */
 672             unsigned old_value =
 673                 *(unsigned *)((unsigned)code_start_addr + offset);
 674
 675             /* If it's within the old_code object then it must be an
 676              * absolute fixup (relative ones are not saved) */
 677             if ((old_value>=(unsigned)old_code)
 678                 && (old_value<((unsigned)old_code + nwords*4)))
 679                 /* So add the dispacement. */
 680                 *(unsigned *)((unsigned)code_start_addr + offset) = old_value
 681                     + displacement;
 682             else
 683                 /* It is outside the old code object so it must be a relative
 684                  * fixup (absolute fixups are not saved). So subtract the
 685                  * displacement. */
 686                 *(unsigned *)((unsigned)code_start_addr + offset) = old_value
 687                     - displacement;
 688         }
 689     }
 690
 691     /* No longer need the fixups. */
 692     new_code->constants[0] = 0;
 693
 694 #ifdef LISP_FEATURE_GENCGC
 695     /* Check for possible errors. */
 696     sniff_code_object(new_code,displacement);
 697 #endif
 698 }
 699 #endif
 700
 701 static lispobj
 702 ptrans_code(lispobj thing)
 703 {
 704     struct code *code, *new;
 705     int nwords;
 706     lispobj func, result;
 707
 708     code = (struct code *)native_pointer(thing);
 709     nwords = HeaderValue(code->header) + fixnum_value(code->code_size);
 710
 711     new = (struct code *)newspace_alloc(nwords,1); /* constant */
 712
 713     bcopy(code, new, nwords * sizeof(lispobj));
 714
 715 #ifdef LISP_FEATURE_X86
 716     apply_code_fixups_during_purify(code,new);
 717 #endif
 718
 719     result = make_lispobj(new, OTHER_POINTER_LOWTAG);
 720
 721     /* Stick in a forwarding pointer for the code object. */
 722     *(lispobj *)code = result;
 723
 724     /* Put in forwarding pointers for all the functions. */
 725     for (func = code->entry_points;
 726          func != NIL;
 727          func = ((struct simple_fun *)native_pointer(func))->next) {
 728
 729         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
 730
 731         *(lispobj *)native_pointer(func) = result + (func - thing);
 732     }
 733
 734     /* Arrange to scavenge the debug info later. */
 735     pscav_later(&new->debug_info, 1);
 736
 737     /* FIXME: why would this be a fixnum? */
 738     /* "why" is a hard word, but apparently for compiled functions the
 739        trace_table_offset contains the length of the instructions, as
 740        a fixnum.  See CODE-INST-AREA-LENGTH in
 741        src/compiler/target-disassem.lisp.  -- CSR, 2004-01-08 */
 742     if (!(fixnump(new->trace_table_offset)))
 743 #if 0
 744         pscav(&new->trace_table_offset, 1, 0);
 745 #else
 746         new->trace_table_offset = NIL; /* limit lifetime */
 747 #endif
 748
 749     /* Scavenge the constants. */
 750     pscav(new->constants, HeaderValue(new->header)-5, 1);
 751
 752     /* Scavenge all the functions. */
 753     pscav(&new->entry_points, 1, 1);
 754     for (func = new->entry_points;
 755          func != NIL;
 756          func = ((struct simple_fun *)native_pointer(func))->next) {
 757         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
 758         gc_assert(!dynamic_pointer_p(func));
 759
 760 #ifdef LISP_FEATURE_X86
 761         /* Temporarily convert the self pointer to a real function pointer. */
 762         ((struct simple_fun *)native_pointer(func))->self
 763             -= FUN_RAW_ADDR_OFFSET;
 764 #endif
 765         pscav(&((struct simple_fun *)native_pointer(func))->self, 2, 1);
 766 #ifdef LISP_FEATURE_X86
 767         ((struct simple_fun *)native_pointer(func))->self
 768             += FUN_RAW_ADDR_OFFSET;
 769 #endif
 770         pscav_later(&((struct simple_fun *)native_pointer(func))->name, 3);
 771     }
 772
 773     return result;
 774 }
 775
 776 static lispobj
 777 ptrans_func(lispobj thing, lispobj header)
 778 {
 779     int nwords;
 780     lispobj code, *new, *old, result;
 781     struct simple_fun *function;
 782
 783     /* Thing can either be a function header, a closure function
 784      * header, a closure, or a funcallable-instance. If it's a closure
 785      * or a funcallable-instance, we do the same as ptrans_boxed.
 786      * Otherwise we have to do something strange, 'cause it is buried
 787      * inside a code object. */
 788
 789     if (widetag_of(header) == SIMPLE_FUN_HEADER_WIDETAG) {
 790
 791         /* We can only end up here if the code object has not been
 792          * scavenged, because if it had been scavenged, forwarding pointers
 793          * would have been left behind for all the entry points. */
 794
 795         function = (struct simple_fun *)native_pointer(thing);
 796         code =
 797             make_lispobj
 798             ((native_pointer(thing) -
 799               (HeaderValue(function->header))), OTHER_POINTER_LOWTAG);
 800
 801         /* This will cause the function's header to be replaced with a
 802          * forwarding pointer. */
 803
 804         ptrans_code(code);
 805
 806         /* So we can just return that. */
 807         return function->header;
 808     }
 809     else {
 810         /* It's some kind of closure-like thing. */
 811         nwords = 1 + HeaderValue(header);
 812         old = (lispobj *)native_pointer(thing);
 813
 814         /* Allocate the new one.  FINs *must* not go in read_only
 815          * space.  Closures can; they never change */
 816
 817         new = newspace_alloc
 818             (nwords,(widetag_of(header)!=FUNCALLABLE_INSTANCE_HEADER_WIDETAG));
 819
 820         /* Copy it. */
 821         bcopy(old, new, nwords * sizeof(lispobj));
 822
 823         /* Deposit forwarding pointer. */
 824         result = make_lispobj(new, lowtag_of(thing));
 825         *old = result;
 826
 827         /* Scavenge it. */
 828         pscav(new, nwords, 0);
 829
 830         return result;
 831     }
 832 }
 833
 834 static lispobj
 835 ptrans_returnpc(lispobj thing, lispobj header)
 836 {
 837     lispobj code, new;
 838
 839     /* Find the corresponding code object. */
 840     code = thing - HeaderValue(header)*sizeof(lispobj);
 841
 842     /* Make sure it's been transported. */
 843     new = *(lispobj *)native_pointer(code);
 844     if (!forwarding_pointer_p(new))
 845         new = ptrans_code(code);
 846
 847     /* Maintain the offset: */
 848     return new + (thing - code);
 849 }
 850
 851 #define WORDS_PER_CONS CEILING(sizeof(struct cons) / sizeof(lispobj), 2)
 852
 853 static lispobj
 854 ptrans_list(lispobj thing, boolean constant)
 855 {
 856     struct cons *old, *new, *orig;
 857     int length;
 858
 859     orig = newspace_alloc(0,constant);
 860     length = 0;
 861
 862     do {
 863         /* Allocate a new cons cell. */
 864         old = (struct cons *)native_pointer(thing);
 865         new = (struct cons *) newspace_alloc(WORDS_PER_CONS,constant);
 866
 867         /* Copy the cons cell and keep a pointer to the cdr. */
 868         new->car = old->car;
 869         thing = new->cdr = old->cdr;
 870
 871         /* Set up the forwarding pointer. */
 872         *(lispobj *)old = make_lispobj(new, LIST_POINTER_LOWTAG);
 873
 874         /* And count this cell. */
 875         length++;
 876     } while (lowtag_of(thing) == LIST_POINTER_LOWTAG &&
 877              dynamic_pointer_p(thing) &&
 878              !(forwarding_pointer_p(*(lispobj *)native_pointer(thing))));
 879
 880     /* Scavenge the list we just copied. */
 881     pscav((lispobj *)orig, length * WORDS_PER_CONS, constant);
 882
 883     return make_lispobj(orig, LIST_POINTER_LOWTAG);
 884 }
 885
 886 static lispobj
 887 ptrans_otherptr(lispobj thing, lispobj header, boolean constant)
 888 {
 889     switch (widetag_of(header)) {
 890         /* FIXME: this needs a reindent */
 891       case BIGNUM_WIDETAG:
 892       case SINGLE_FLOAT_WIDETAG:
 893       case DOUBLE_FLOAT_WIDETAG:
 894 #ifdef LONG_FLOAT_WIDETAG
 895       case LONG_FLOAT_WIDETAG:
 896 #endif
 897 #ifdef COMPLEX_SINGLE_FLOAT_WIDETAG
 898       case COMPLEX_SINGLE_FLOAT_WIDETAG:
 899 #endif
 900 #ifdef COMPLEX_DOUBLE_FLOAT_WIDETAG
 901       case COMPLEX_DOUBLE_FLOAT_WIDETAG:
 902 #endif
 903 #ifdef COMPLEX_LONG_FLOAT_WIDETAG
 904       case COMPLEX_LONG_FLOAT_WIDETAG:
 905 #endif
 906       case SAP_WIDETAG:
 907           return ptrans_unboxed(thing, header);
 908
 909       case RATIO_WIDETAG:
 910       case COMPLEX_WIDETAG:
 911       case SIMPLE_ARRAY_WIDETAG:
 912       case COMPLEX_BASE_STRING_WIDETAG:
 913       case COMPLEX_BIT_VECTOR_WIDETAG:
 914       case COMPLEX_VECTOR_NIL_WIDETAG:
 915       case COMPLEX_VECTOR_WIDETAG:
 916       case COMPLEX_ARRAY_WIDETAG:
 917         return ptrans_boxed(thing, header, constant);
 918
 919       case VALUE_CELL_HEADER_WIDETAG:
 920       case WEAK_POINTER_WIDETAG:
 921         return ptrans_boxed(thing, header, 0);
 922
 923       case SYMBOL_HEADER_WIDETAG:
 924         return ptrans_boxed(thing, header, 0);
 925
 926       case SIMPLE_ARRAY_NIL_WIDETAG:
 927         return ptrans_vector(thing, 0, 0, 0, constant);
 928
 929       case SIMPLE_BASE_STRING_WIDETAG:
 930         return ptrans_vector(thing, 8, 1, 0, constant);
 931
 932       case SIMPLE_BIT_VECTOR_WIDETAG:
 933         return ptrans_vector(thing, 1, 0, 0, constant);
 934
 935       case SIMPLE_VECTOR_WIDETAG:
 936         return ptrans_vector(thing, 32, 0, 1, constant);
 937
 938       case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
 939         return ptrans_vector(thing, 2, 0, 0, constant);
 940
 941       case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
 942         return ptrans_vector(thing, 4, 0, 0, constant);
 943
 944       case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
 945 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
 946       case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
 947       case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
 948 #endif
 949         return ptrans_vector(thing, 8, 0, 0, constant);
 950
 951       case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
 952 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
 953       case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
 954       case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
 955 #endif
 956         return ptrans_vector(thing, 16, 0, 0, constant);
 957
 958       case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
 959 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
 960       case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
 961       case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
 962 #endif
 963 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
 964       case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
 965       case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
 966 #endif
 967         return ptrans_vector(thing, 32, 0, 0, constant);
 968
 969       case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
 970         return ptrans_vector(thing, 32, 0, 0, constant);
 971
 972       case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
 973         return ptrans_vector(thing, 64, 0, 0, constant);
 974
 975 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
 976       case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
 977 #ifdef LISP_FEATURE_X86
 978         return ptrans_vector(thing, 96, 0, 0, constant);
 979 #endif
 980 #ifdef sparc
 981         return ptrans_vector(thing, 128, 0, 0, constant);
 982 #endif
 983 #endif
 984
 985 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
 986       case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
 987         return ptrans_vector(thing, 64, 0, 0, constant);
 988 #endif
 989
 990 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
 991       case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
 992         return ptrans_vector(thing, 128, 0, 0, constant);
 993 #endif
 994
 995 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
 996       case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
 997 #ifdef LISP_FEATURE_X86
 998         return ptrans_vector(thing, 192, 0, 0, constant);
 999 #endif
1000 #ifdef sparc
1001         return ptrans_vector(thing, 256, 0, 0, constant);
1002 #endif
1003 #endif
1004
1005       case CODE_HEADER_WIDETAG:
1006         return ptrans_code(thing);
1007
1008       case RETURN_PC_HEADER_WIDETAG:
1009         return ptrans_returnpc(thing, header);
1010
1011       case FDEFN_WIDETAG:
1012         return ptrans_fdefn(thing, header);
1013
1014       default:
1015         /* Should only come across other pointers to the above stuff. */
1016         gc_abort();
1017         return NIL;
1018     }
1019 }
1020
1021 static int
1022 pscav_fdefn(struct fdefn *fdefn)
1023 {
1024     boolean fix_func;
1025
1026     fix_func = ((char *)(fdefn->fun+FUN_RAW_ADDR_OFFSET) == fdefn->raw_addr);
1027     pscav(&fdefn->name, 1, 1);
1028     pscav(&fdefn->fun, 1, 0);
1029     if (fix_func)
1030         fdefn->raw_addr = (char *)(fdefn->fun + FUN_RAW_ADDR_OFFSET);
1031     return sizeof(struct fdefn) / sizeof(lispobj);
1032 }
1033
1034 #ifdef LISP_FEATURE_X86
1035 /* now putting code objects in static space */
1036 static int
1037 pscav_code(struct code*code)
1038 {
1039     int nwords;
1040     lispobj func;
1041     nwords = HeaderValue(code->header) + fixnum_value(code->code_size);
1042
1043     /* Arrange to scavenge the debug info later. */
1044     pscav_later(&code->debug_info, 1);
1045
1046     /* Scavenge the constants. */
1047     pscav(code->constants, HeaderValue(code->header)-5, 1);
1048
1049     /* Scavenge all the functions. */
1050     pscav(&code->entry_points, 1, 1);
1051     for (func = code->entry_points;
1052          func != NIL;
1053          func = ((struct simple_fun *)native_pointer(func))->next) {
1054         gc_assert(lowtag_of(func) == FUN_POINTER_LOWTAG);
1055         gc_assert(!dynamic_pointer_p(func));
1056
1057 #ifdef LISP_FEATURE_X86
1058         /* Temporarily convert the self pointer to a real function
1059          * pointer. */
1060         ((struct simple_fun *)native_pointer(func))->self
1061             -= FUN_RAW_ADDR_OFFSET;
1062 #endif
1063         pscav(&((struct simple_fun *)native_pointer(func))->self, 2, 1);
1064 #ifdef LISP_FEATURE_X86
1065         ((struct simple_fun *)native_pointer(func))->self
1066             += FUN_RAW_ADDR_OFFSET;
1067 #endif
1068         pscav_later(&((struct simple_fun *)native_pointer(func))->name, 3);
1069     }
1070
1071     return CEILING(nwords,2);
1072 }
1073 #endif
1074
1075 static lispobj *
1076 pscav(lispobj *addr, int nwords, boolean constant)
1077 {
1078     lispobj thing, *thingp, header;
1079     int count = 0; /* (0 = dummy init value to stop GCC warning) */
1080     struct vector *vector;
1081
1082     while (nwords > 0) {
1083         thing = *addr;
1084         if (is_lisp_pointer(thing)) {
1085             /* It's a pointer. Is it something we might have to move? */
1086             if (dynamic_pointer_p(thing)) {
1087                 /* Maybe. Have we already moved it? */
1088                 thingp = (lispobj *)native_pointer(thing);
1089                 header = *thingp;
1090                 if (is_lisp_pointer(header) && forwarding_pointer_p(header))
1091                     /* Yep, so just copy the forwarding pointer. */
1092                     thing = header;
1093                 else {
1094                     /* Nope, copy the object. */
1095                     switch (lowtag_of(thing)) {
1096                       case FUN_POINTER_LOWTAG:
1097                         thing = ptrans_func(thing, header);
1098                         break;
1099
1100                       case LIST_POINTER_LOWTAG:
1101                         thing = ptrans_list(thing, constant);
1102                         break;
1103
1104                       case INSTANCE_POINTER_LOWTAG:
1105                         thing = ptrans_instance(thing, header, constant);
1106                         break;
1107
1108                       case OTHER_POINTER_LOWTAG:
1109                         thing = ptrans_otherptr(thing, header, constant);
1110                         break;
1111
1112                       default:
1113                         /* It was a pointer, but not one of them? */
1114                         gc_abort();
1115                     }
1116                 }
1117                 *addr = thing;
1118             }
1119             count = 1;
1120         }
1121         else if (thing & 3) {   /* FIXME: 3?  not 2? */
1122             /* It's an other immediate. Maybe the header for an unboxed */
1123             /* object. */
1124             switch (widetag_of(thing)) {
1125               case BIGNUM_WIDETAG:
1126               case SINGLE_FLOAT_WIDETAG:
1127               case DOUBLE_FLOAT_WIDETAG:
1128 #ifdef LONG_FLOAT_WIDETAG
1129               case LONG_FLOAT_WIDETAG:
1130 #endif
1131               case SAP_WIDETAG:
1132                 /* It's an unboxed simple object. */
1133                 count = HeaderValue(thing)+1;
1134                 break;
1135
1136               case SIMPLE_VECTOR_WIDETAG:
1137                   if (HeaderValue(thing) == subtype_VectorValidHashing) {
1138                     *addr = (subtype_VectorMustRehash << N_WIDETAG_BITS) |
1139                         SIMPLE_VECTOR_WIDETAG;
1140                   }
1141                 count = 1;
1142                 break;
1143
1144               case SIMPLE_ARRAY_NIL_WIDETAG:
1145                 count = 2;
1146                 break;
1147
1148               case SIMPLE_BASE_STRING_WIDETAG:
1149                 vector = (struct vector *)addr;
1150                 count = CEILING(NWORDS(fixnum_value(vector->length)+1,4)+2,2);
1151                 break;
1152
1153               case SIMPLE_BIT_VECTOR_WIDETAG:
1154                 vector = (struct vector *)addr;
1155                 count = CEILING(NWORDS(fixnum_value(vector->length),32)+2,2);
1156                 break;
1157
1158               case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
1159                 vector = (struct vector *)addr;
1160                 count = CEILING(NWORDS(fixnum_value(vector->length),16)+2,2);
1161                 break;
1162
1163               case SIMPLE_ARRAY_UNSIGNED_BYTE_4_WIDETAG:
1164                 vector = (struct vector *)addr;
1165                 count = CEILING(NWORDS(fixnum_value(vector->length),8)+2,2);
1166                 break;
1167
1168               case SIMPLE_ARRAY_UNSIGNED_BYTE_8_WIDETAG:
1169 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG
1170               case SIMPLE_ARRAY_SIGNED_BYTE_8_WIDETAG:
1171               case SIMPLE_ARRAY_UNSIGNED_BYTE_7_WIDETAG:
1172 #endif
1173                 vector = (struct vector *)addr;
1174                 count = CEILING(NWORDS(fixnum_value(vector->length),4)+2,2);
1175                 break;
1176
1177               case SIMPLE_ARRAY_UNSIGNED_BYTE_16_WIDETAG:
1178 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG
1179               case SIMPLE_ARRAY_SIGNED_BYTE_16_WIDETAG:
1180               case SIMPLE_ARRAY_UNSIGNED_BYTE_15_WIDETAG:
1181 #endif
1182                 vector = (struct vector *)addr;
1183                 count = CEILING(NWORDS(fixnum_value(vector->length),2)+2,2);
1184                 break;
1185
1186               case SIMPLE_ARRAY_UNSIGNED_BYTE_32_WIDETAG:
1187 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG
1188               case SIMPLE_ARRAY_SIGNED_BYTE_30_WIDETAG:
1189               case SIMPLE_ARRAY_UNSIGNED_BYTE_29_WIDETAG:
1190 #endif
1191 #ifdef SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG
1192               case SIMPLE_ARRAY_SIGNED_BYTE_32_WIDETAG:
1193               case SIMPLE_ARRAY_UNSIGNED_BYTE_31_WIDETAG:
1194 #endif
1195                 vector = (struct vector *)addr;
1196                 count = CEILING(fixnum_value(vector->length)+2,2);
1197                 break;
1198
1199               case SIMPLE_ARRAY_SINGLE_FLOAT_WIDETAG:
1200                 vector = (struct vector *)addr;
1201                 count = CEILING(fixnum_value(vector->length)+2,2);
1202                 break;
1203
1204               case SIMPLE_ARRAY_DOUBLE_FLOAT_WIDETAG:
1205 #ifdef SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG
1206               case SIMPLE_ARRAY_COMPLEX_SINGLE_FLOAT_WIDETAG:
1207 #endif
1208                 vector = (struct vector *)addr;
1209                 count = fixnum_value(vector->length)*2+2;
1210                 break;
1211
1212 #ifdef SIMPLE_ARRAY_LONG_FLOAT_WIDETAG
1213               case SIMPLE_ARRAY_LONG_FLOAT_WIDETAG:
1214                 vector = (struct vector *)addr;
1215 #ifdef LISP_FEATURE_X86
1216                 count = fixnum_value(vector->length)*3+2;
1217 #endif
1218 #ifdef sparc
1219                 count = fixnum_value(vector->length)*4+2;
1220 #endif
1221                 break;
1222 #endif
1223
1224 #ifdef SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG
1225               case SIMPLE_ARRAY_COMPLEX_DOUBLE_FLOAT_WIDETAG:
1226                 vector = (struct vector *)addr;
1227                 count = fixnum_value(vector->length)*4+2;
1228                 break;
1229 #endif
1230
1231 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
1232               case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
1233                 vector = (struct vector *)addr;
1234 #ifdef LISP_FEATURE_X86
1235                 count = fixnum_value(vector->length)*6+2;
1236 #endif
1237 #ifdef sparc
1238                 count = fixnum_value(vector->length)*8+2;
1239 #endif
1240                 break;
1241 #endif
1242
1243               case CODE_HEADER_WIDETAG:
1244 #ifndef LISP_FEATURE_X86
1245                 gc_abort(); /* no code headers in static space */
1246 #else
1247                 count = pscav_code((struct code*)addr);
1248 #endif
1249                 break;
1250
1251               case SIMPLE_FUN_HEADER_WIDETAG:
1252               case RETURN_PC_HEADER_WIDETAG:
1253                 /* We should never hit any of these, 'cause they occur
1254                  * buried in the middle of code objects. */
1255                 gc_abort();
1256                 break;
1257
1258 #ifdef LISP_FEATURE_X86
1259               case CLOSURE_HEADER_WIDETAG:
1260               case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
1261                 /* The function self pointer needs special care on the
1262                  * x86 because it is the real entry point. */
1263                 {
1264                   lispobj fun = ((struct closure *)addr)->fun
1265                     - FUN_RAW_ADDR_OFFSET;
1266                   pscav(&fun, 1, constant);
1267                   ((struct closure *)addr)->fun = fun + FUN_RAW_ADDR_OFFSET;
1268                 }
1269                 count = 2;
1270                 break;
1271 #endif
1272
1273               case WEAK_POINTER_WIDETAG:
1274                 /* Weak pointers get preserved during purify, 'cause I
1275                  * don't feel like figuring out how to break them. */
1276                 pscav(addr+1, 2, constant);
1277                 count = 4;
1278                 break;
1279
1280               case FDEFN_WIDETAG:
1281                 /* We have to handle fdefn objects specially, so we
1282                  * can fix up the raw function address. */
1283                 count = pscav_fdefn((struct fdefn *)addr);
1284                 break;
1285
1286               default:
1287                 count = 1;
1288                 break;
1289             }
1290         }
1291         else {
1292             /* It's a fixnum. */
1293             count = 1;
1294         }
1295
1296         addr += count;
1297         nwords -= count;
1298     }
1299
1300     return addr;
1301 }
1302
1303 int
1304 purify(lispobj static_roots, lispobj read_only_roots)
1305 {
1306     lispobj *clean;
1307     int count, i;
1308     struct later *laters, *next;
1309     struct thread *thread;
1310
1311     if(all_threads->next) {
1312         /* FIXME: there should be _some_ sensible error reporting
1313          * convention.  See following comment too */
1314         fprintf(stderr,"Can't purify when more than one thread exists\n");
1315         fflush(stderr);
1316         return 0;
1317     }
1318
1319 #ifdef PRINTNOISE
1320     printf("[doing purification:");
1321     fflush(stdout);
1322 #endif
1323 #ifdef LISP_FEATURE_GENCGC
1324     gc_alloc_update_all_page_tables();
1325 #endif
1326     for_each_thread(thread)
1327         if (fixnum_value(SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX,thread)) != 0) {
1328         /* FIXME: 1. What does this mean? 2. It shouldn't be reporting
1329          * its error simply by a. printing a string b. to stdout instead
1330          * of stderr. */
1331         printf(" Ack! Can't purify interrupt contexts. ");
1332         fflush(stdout);
1333         return 0;
1334     }
1335
1336 #if defined(LISP_FEATURE_X86)
1337     dynamic_space_free_pointer =
1338       (lispobj*)SymbolValue(ALLOCATION_POINTER,0);
1339 #endif
1340
1341     read_only_end = read_only_free =
1342         (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER,0);
1343     static_end = static_free =
1344         (lispobj *)SymbolValue(STATIC_SPACE_FREE_POINTER,0);
1345
1346 #ifdef PRINTNOISE
1347     printf(" roots");
1348     fflush(stdout);
1349 #endif
1350
1351 #if (defined(LISP_FEATURE_GENCGC) && defined(LISP_FEATURE_X86))
1352     /* note this expects only one thread to be active.  We'd have to
1353      * stop all the others in the same way as GC does if we wanted
1354      * PURIFY to work when >1 thread exists */
1355     setup_i386_stack_scav(((&static_roots)-2),
1356                           ((void *)all_threads->control_stack_end));
1357 #endif
1358
1359     pscav(&static_roots, 1, 0);
1360     pscav(&read_only_roots, 1, 1);
1361
1362 #ifdef PRINTNOISE
1363     printf(" handlers");
1364     fflush(stdout);
1365 #endif
1366     pscav((lispobj *) all_threads->interrupt_data->interrupt_handlers,
1367           sizeof(all_threads->interrupt_data->interrupt_handlers)
1368           / sizeof(lispobj),
1369           0);
1370
1371 #ifdef PRINTNOISE
1372     printf(" stack");
1373     fflush(stdout);
1374 #endif
1375 #ifndef LISP_FEATURE_X86
1376     pscav((lispobj *)all_threads->control_stack_start,
1377           current_control_stack_pointer -
1378           all_threads->control_stack_start,
1379           0);
1380 #else
1381 #ifdef LISP_FEATURE_GENCGC
1382     pscav_i386_stack();
1383 #endif
1384 #endif
1385
1386 #ifdef PRINTNOISE
1387     printf(" bindings");
1388     fflush(stdout);
1389 #endif
1390 #if !defined(LISP_FEATURE_X86)
1391     pscav( (lispobj *)all_threads->binding_stack_start,
1392           (lispobj *)current_binding_stack_pointer -
1393            all_threads->binding_stack_start,
1394           0);
1395 #else
1396     for_each_thread(thread) {
1397         pscav( (lispobj *)thread->binding_stack_start,
1398                (lispobj *)SymbolValue(BINDING_STACK_POINTER,thread) -
1399                (lispobj *)thread->binding_stack_start,
1400           0);
1401         pscav( (lispobj *) (thread+1),
1402                fixnum_value(SymbolValue(FREE_TLS_INDEX,0)) -
1403                (sizeof (struct thread))/(sizeof (lispobj)),
1404           0);
1405     }
1406
1407
1408 #endif
1409
1410     /* The original CMU CL code had scavenge-read-only-space code
1411      * controlled by the Lisp-level variable
1412      * *SCAVENGE-READ-ONLY-SPACE*. It was disabled by default, and it
1413      * wasn't documented under what circumstances it was useful or
1414      * safe to turn it on, so it's been turned off in SBCL. If you
1415      * want/need this functionality, and can test and document it,
1416      * please submit a patch. */
1417 #if 0
1418     if (SymbolValue(SCAVENGE_READ_ONLY_SPACE) != UNBOUND_MARKER_WIDETAG
1419         && SymbolValue(SCAVENGE_READ_ONLY_SPACE) != NIL) {
1420       unsigned  read_only_space_size =
1421           (lispobj *)SymbolValue(READ_ONLY_SPACE_FREE_POINTER) -
1422           (lispobj *)READ_ONLY_SPACE_START;
1423       fprintf(stderr,
1424               "scavenging read only space: %d bytes\n",
1425               read_only_space_size * sizeof(lispobj));
1426       pscav( (lispobj *)READ_ONLY_SPACE_START, read_only_space_size, 0);
1427     }
1428 #endif
1429
1430 #ifdef PRINTNOISE
1431     printf(" static");
1432     fflush(stdout);
1433 #endif
1434     clean = (lispobj *)STATIC_SPACE_START;
1435     do {
1436         while (clean != static_free)
1437             clean = pscav(clean, static_free - clean, 0);
1438         laters = later_blocks;
1439         count = later_count;
1440         later_blocks = NULL;
1441         later_count = 0;
1442         while (laters != NULL) {
1443             for (i = 0; i < count; i++) {
1444                 if (laters->u[i].count == 0) {
1445                     ;
1446                 } else if (laters->u[i].count <= LATERMAXCOUNT) {
1447                     pscav(laters->u[i+1].ptr, laters->u[i].count, 1);
1448                     i++;
1449                 } else {
1450                     pscav(laters->u[i].ptr, 1, 1);
1451                 }
1452             }
1453             next = laters->next;
1454             free(laters);
1455             laters = next;
1456             count = LATERBLOCKSIZE;
1457         }
1458     } while (clean != static_free || later_blocks != NULL);
1459
1460 #ifdef PRINTNOISE
1461     printf(" cleanup");
1462     fflush(stdout);
1463 #endif
1464
1465     os_zero((os_vm_address_t) current_dynamic_space,
1466             (os_vm_size_t) DYNAMIC_SPACE_SIZE);
1467
1468     /* Zero the stack. Note that the stack is also zeroed by SUB-GC
1469      * calling SCRUB-CONTROL-STACK - this zeros the stack on the x86. */
1470 #ifndef LISP_FEATURE_X86
1471     os_zero((os_vm_address_t) current_control_stack_pointer,
1472             (os_vm_size_t)
1473             ((all_threads->control_stack_end -
1474               current_control_stack_pointer) * sizeof(lispobj)));
1475 #endif
1476
1477     /* It helps to update the heap free pointers so that free_heap can
1478      * verify after it's done. */
1479     SetSymbolValue(READ_ONLY_SPACE_FREE_POINTER, (lispobj)read_only_free,0);
1480     SetSymbolValue(STATIC_SPACE_FREE_POINTER, (lispobj)static_free,0);
1481
1482 #if !defined(LISP_FEATURE_X86)
1483     dynamic_space_free_pointer = current_dynamic_space;
1484     set_auto_gc_trigger(bytes_consed_between_gcs);
1485 #else
1486 #if defined LISP_FEATURE_GENCGC
1487     gc_free_heap();
1488 #else
1489 #error unsupported case /* in CMU CL, was "ibmrt using GC" */
1490 #endif
1491 #endif
1492
1493 #ifdef PRINTNOISE
1494     printf(" done]\n");
1495     fflush(stdout);
1496 #endif
1497     return 0;
1498 }