2 * GENerational Conservative Garbage Collector for SBCL x86
6 * This software is part of the SBCL system. See the README file for
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.
17 * For a review of garbage collection techniques (e.g. generational
18 * GC) and terminology (e.g. "scavenging") see Paul R. Wilson,
19 * "Uniprocessor Garbage Collection Techniques". As of 20000618, this
20 * had been accepted for _ACM Computing Surveys_ and was available
21 * as a PostScript preprint through
22 * <http://www.cs.utexas.edu/users/oops/papers.html>
24 * <ftp://ftp.cs.utexas.edu/pub/garbage/bigsurv.ps>.
34 #include "interrupt.h"
41 /* a function defined externally in assembly language, called from
43 void do_pending_interrupt(void);
49 /* the number of actual generations. (The number of 'struct
50 * generation' objects is one more than this, because one object
51 * serves as scratch when GC'ing.) */
52 #define NUM_GENERATIONS 6
54 /* Should we use page protection to help avoid the scavenging of pages
55 * that don't have pointers to younger generations? */
56 boolean enable_page_protection = 1;
58 /* Should we unmap a page and re-mmap it to have it zero filled? */
59 #if defined(__FreeBSD__) || defined(__OpenBSD__)
60 /* comment from cmucl-2.4.8: This can waste a lot of swap on FreeBSD
61 * so don't unmap there.
63 * The CMU CL comment didn't specify a version, but was probably an
64 * old version of FreeBSD (pre-4.0), so this might no longer be true.
65 * OTOH, if it is true, this behavior might exist on OpenBSD too, so
66 * for now we don't unmap there either. -- WHN 2001-04-07 */
67 boolean gencgc_unmap_zero = 0;
69 boolean gencgc_unmap_zero = 1;
72 /* the minimum size (in bytes) for a large object*/
73 unsigned large_object_size = 4 * 4096;
79 #define gc_abort() lose("GC invariant lost, file \"%s\", line %d", \
82 /* FIXME: In CMU CL, this was "#if 0" with no explanation. Find out
83 * how much it costs to make it "#if 1". If it's not too expensive,
86 #define gc_assert(ex) do { \
87 if (!(ex)) gc_abort(); \
93 /* the verbosity level. All non-error messages are disabled at level 0;
94 * and only a few rare messages are printed at level 1. */
95 unsigned gencgc_verbose = (QSHOW ? 1 : 0);
97 /* FIXME: At some point enable the various error-checking things below
98 * and see what they say. */
100 /* We hunt for pointers to old-space, when GCing generations >= verify_gen.
101 * Set verify_gens to NUM_GENERATIONS to disable this kind of check. */
102 int verify_gens = NUM_GENERATIONS;
104 /* Should we do a pre-scan verify of generation 0 before it's GCed? */
105 boolean pre_verify_gen_0 = 0;
107 /* Should we check for bad pointers after gc_free_heap is called
108 * from Lisp PURIFY? */
109 boolean verify_after_free_heap = 0;
111 /* Should we print a note when code objects are found in the dynamic space
112 * during a heap verify? */
113 boolean verify_dynamic_code_check = 0;
115 /* Should we check code objects for fixup errors after they are transported? */
116 boolean check_code_fixups = 0;
118 /* Should we check that newly allocated regions are zero filled? */
119 boolean gencgc_zero_check = 0;
121 /* Should we check that the free space is zero filled? */
122 boolean gencgc_enable_verify_zero_fill = 0;
124 /* Should we check that free pages are zero filled during gc_free_heap
125 * called after Lisp PURIFY? */
126 boolean gencgc_zero_check_during_free_heap = 0;
129 * GC structures and variables
132 /* the total bytes allocated. These are seen by Lisp DYNAMIC-USAGE. */
133 unsigned long bytes_allocated = 0;
134 static unsigned long auto_gc_trigger = 0;
136 /* the source and destination generations. These are set before a GC starts
138 static int from_space;
139 static int new_space;
141 /* FIXME: It would be nice to use this symbolic constant instead of
142 * bare 4096 almost everywhere. We could also use an assertion that
143 * it's equal to getpagesize(). */
144 #define PAGE_BYTES 4096
146 /* An array of page structures is statically allocated.
147 * This helps quickly map between an address its page structure.
148 * NUM_PAGES is set from the size of the dynamic space. */
149 struct page page_table[NUM_PAGES];
151 /* To map addresses to page structures the address of the first page
153 static void *heap_base = NULL;
155 /* Calculate the start address for the given page number. */
157 page_address(int page_num)
159 return (heap_base + (page_num * 4096));
162 /* Find the page index within the page_table for the given
163 * address. Return -1 on failure. */
165 find_page_index(void *addr)
167 int index = addr-heap_base;
170 index = ((unsigned int)index)/4096;
171 if (index < NUM_PAGES)
178 /* a structure to hold the state of a generation */
181 /* the first page that gc_alloc() checks on its next call */
182 int alloc_start_page;
184 /* the first page that gc_alloc_unboxed() checks on its next call */
185 int alloc_unboxed_start_page;
187 /* the first page that gc_alloc_large (boxed) considers on its next
188 * call. (Although it always allocates after the boxed_region.) */
189 int alloc_large_start_page;
191 /* the first page that gc_alloc_large (unboxed) considers on its
192 * next call. (Although it always allocates after the
193 * current_unboxed_region.) */
194 int alloc_large_unboxed_start_page;
196 /* the bytes allocated to this generation */
199 /* the number of bytes at which to trigger a GC */
202 /* to calculate a new level for gc_trigger */
203 int bytes_consed_between_gc;
205 /* the number of GCs since the last raise */
208 /* the average age after which a GC will raise objects to the
212 /* the cumulative sum of the bytes allocated to this generation. It is
213 * cleared after a GC on this generations, and update before new
214 * objects are added from a GC of a younger generation. Dividing by
215 * the bytes_allocated will give the average age of the memory in
216 * this generation since its last GC. */
217 int cum_sum_bytes_allocated;
219 /* a minimum average memory age before a GC will occur helps
220 * prevent a GC when a large number of new live objects have been
221 * added, in which case a GC could be a waste of time */
222 double min_av_mem_age;
225 /* an array of generation structures. There needs to be one more
226 * generation structure than actual generations as the oldest
227 * generation is temporarily raised then lowered. */
228 static struct generation generations[NUM_GENERATIONS+1];
230 /* the oldest generation that is will currently be GCed by default.
231 * Valid values are: 0, 1, ... (NUM_GENERATIONS-1)
233 * The default of (NUM_GENERATIONS-1) enables GC on all generations.
235 * Setting this to 0 effectively disables the generational nature of
236 * the GC. In some applications generational GC may not be useful
237 * because there are no long-lived objects.
239 * An intermediate value could be handy after moving long-lived data
240 * into an older generation so an unnecessary GC of this long-lived
241 * data can be avoided. */
242 unsigned int gencgc_oldest_gen_to_gc = NUM_GENERATIONS-1;
244 /* The maximum free page in the heap is maintained and used to update
245 * ALLOCATION_POINTER which is used by the room function to limit its
246 * search of the heap. XX Gencgc obviously needs to be better
247 * integrated with the Lisp code. */
248 static int last_free_page;
249 static int last_used_page = 0;
252 * miscellaneous heap functions
255 /* Count the number of pages which are write-protected within the
256 * given generation. */
258 count_write_protect_generation_pages(int generation)
263 for (i = 0; i < last_free_page; i++)
264 if ((page_table[i].allocated != FREE_PAGE)
265 && (page_table[i].gen == generation)
266 && (page_table[i].write_protected == 1))
271 /* Count the number of pages within the given generation. */
273 count_generation_pages(int generation)
278 for (i = 0; i < last_free_page; i++)
279 if ((page_table[i].allocated != 0)
280 && (page_table[i].gen == generation))
285 /* Count the number of dont_move pages. */
287 count_dont_move_pages(void)
291 for (i = 0; i < last_free_page; i++) {
292 if ((page_table[i].allocated != 0) && (page_table[i].dont_move != 0)) {
299 /* Work through the pages and add up the number of bytes used for the
300 * given generation. */
302 count_generation_bytes_allocated (int gen)
306 for (i = 0; i < last_free_page; i++) {
307 if ((page_table[i].allocated != 0) && (page_table[i].gen == gen))
308 result += page_table[i].bytes_used;
313 /* Return the average age of the memory in a generation. */
315 gen_av_mem_age(int gen)
317 if (generations[gen].bytes_allocated == 0)
321 ((double)generations[gen].cum_sum_bytes_allocated)
322 / ((double)generations[gen].bytes_allocated);
325 /* The verbose argument controls how much to print: 0 for normal
326 * level of detail; 1 for debugging. */
328 print_generation_stats(int verbose) /* FIXME: should take FILE argument */
333 /* This code uses the FP instructions which may be set up for Lisp
334 * so they need to be saved and reset for C. */
337 /* number of generations to print */
339 gens = NUM_GENERATIONS+1;
341 gens = NUM_GENERATIONS;
343 /* Print the heap stats. */
345 " Generation Boxed Unboxed LB LUB Alloc Waste Trig WP GCs Mem-age\n");
347 for (i = 0; i < gens; i++) {
351 int large_boxed_cnt = 0;
352 int large_unboxed_cnt = 0;
354 for (j = 0; j < last_free_page; j++)
355 if (page_table[j].gen == i) {
357 /* Count the number of boxed pages within the given
359 if (page_table[j].allocated == BOXED_PAGE) {
360 if (page_table[j].large_object)
366 /* Count the number of unboxed pages within the given
368 if (page_table[j].allocated == UNBOXED_PAGE) {
369 if (page_table[j].large_object)
376 gc_assert(generations[i].bytes_allocated
377 == count_generation_bytes_allocated(i));
379 " %8d: %5d %5d %5d %5d %8d %5d %8d %4d %3d %7.4f\n",
381 boxed_cnt, unboxed_cnt, large_boxed_cnt, large_unboxed_cnt,
382 generations[i].bytes_allocated,
383 (count_generation_pages(i)*4096
384 - generations[i].bytes_allocated),
385 generations[i].gc_trigger,
386 count_write_protect_generation_pages(i),
387 generations[i].num_gc,
390 fprintf(stderr," Total bytes allocated=%ld\n", bytes_allocated);
392 fpu_restore(fpu_state);
396 * allocation routines
400 * To support quick and inline allocation, regions of memory can be
401 * allocated and then allocated from with just a free pointer and a
402 * check against an end address.
404 * Since objects can be allocated to spaces with different properties
405 * e.g. boxed/unboxed, generation, ages; there may need to be many
406 * allocation regions.
408 * Each allocation region may be start within a partly used page. Many
409 * features of memory use are noted on a page wise basis, e.g. the
410 * generation; so if a region starts within an existing allocated page
411 * it must be consistent with this page.
413 * During the scavenging of the newspace, objects will be transported
414 * into an allocation region, and pointers updated to point to this
415 * allocation region. It is possible that these pointers will be
416 * scavenged again before the allocation region is closed, e.g. due to
417 * trans_list which jumps all over the place to cleanup the list. It
418 * is important to be able to determine properties of all objects
419 * pointed to when scavenging, e.g to detect pointers to the oldspace.
420 * Thus it's important that the allocation regions have the correct
421 * properties set when allocated, and not just set when closed. The
422 * region allocation routines return regions with the specified
423 * properties, and grab all the pages, setting their properties
424 * appropriately, except that the amount used is not known.
426 * These regions are used to support quicker allocation using just a
427 * free pointer. The actual space used by the region is not reflected
428 * in the pages tables until it is closed. It can't be scavenged until
431 * When finished with the region it should be closed, which will
432 * update the page tables for the actual space used returning unused
433 * space. Further it may be noted in the new regions which is
434 * necessary when scavenging the newspace.
436 * Large objects may be allocated directly without an allocation
437 * region, the page tables are updated immediately.
439 * Unboxed objects don't contain pointers to other objects and so
440 * don't need scavenging. Further they can't contain pointers to
441 * younger generations so WP is not needed. By allocating pages to
442 * unboxed objects the whole page never needs scavenging or
443 * write-protecting. */
445 /* We are only using two regions at present. Both are for the current
446 * newspace generation. */
447 struct alloc_region boxed_region;
448 struct alloc_region unboxed_region;
450 /* XX hack. Current Lisp code uses the following. Need copying in/out. */
451 void *current_region_free_pointer;
452 void *current_region_end_addr;
454 /* The generation currently being allocated to. */
455 static int gc_alloc_generation;
457 /* Find a new region with room for at least the given number of bytes.
459 * It starts looking at the current generation's alloc_start_page. So
460 * may pick up from the previous region if there is enough space. This
461 * keeps the allocation contiguous when scavenging the newspace.
463 * The alloc_region should have been closed by a call to
464 * gc_alloc_update_page_tables(), and will thus be in an empty state.
466 * To assist the scavenging functions write-protected pages are not
467 * used. Free pages should not be write-protected.
469 * It is critical to the conservative GC that the start of regions be
470 * known. To help achieve this only small regions are allocated at a
473 * During scavenging, pointers may be found to within the current
474 * region and the page generation must be set so that pointers to the
475 * from space can be recognized. Therefore the generation of pages in
476 * the region are set to gc_alloc_generation. To prevent another
477 * allocation call using the same pages, all the pages in the region
478 * are allocated, although they will initially be empty.
481 gc_alloc_new_region(int nbytes, int unboxed, struct alloc_region *alloc_region)
493 "/alloc_new_region for %d bytes from gen %d\n",
494 nbytes, gc_alloc_generation));
497 /* Check that the region is in a reset state. */
498 gc_assert((alloc_region->first_page == 0)
499 && (alloc_region->last_page == -1)
500 && (alloc_region->free_pointer == alloc_region->end_addr));
504 generations[gc_alloc_generation].alloc_unboxed_start_page;
507 generations[gc_alloc_generation].alloc_start_page;
510 /* Search for a contiguous free region of at least nbytes with the
511 * given properties: boxed/unboxed, generation. */
513 first_page = restart_page;
515 /* First search for a page with at least 32 bytes free, which is
516 * not write-protected, and which is not marked dont_move.
518 * FIXME: This looks extremely similar, perhaps identical, to
519 * code in gc_alloc_large(). It should be shared somehow. */
520 while ((first_page < NUM_PAGES)
521 && (page_table[first_page].allocated != FREE_PAGE) /* not free page */
523 (page_table[first_page].allocated != UNBOXED_PAGE))
525 (page_table[first_page].allocated != BOXED_PAGE))
526 || (page_table[first_page].large_object != 0)
527 || (page_table[first_page].gen != gc_alloc_generation)
528 || (page_table[first_page].bytes_used >= (4096-32))
529 || (page_table[first_page].write_protected != 0)
530 || (page_table[first_page].dont_move != 0)))
532 /* Check for a failure. */
533 if (first_page >= NUM_PAGES) {
535 "Argh! gc_alloc_new_region failed on first_page, nbytes=%d.\n",
537 print_generation_stats(1);
541 gc_assert(page_table[first_page].write_protected == 0);
545 "/first_page=%d bytes_used=%d\n",
546 first_page, page_table[first_page].bytes_used));
549 /* Now search forward to calculate the available region size. It
550 * tries to keeps going until nbytes are found and the number of
551 * pages is greater than some level. This helps keep down the
552 * number of pages in a region. */
553 last_page = first_page;
554 bytes_found = 4096 - page_table[first_page].bytes_used;
556 while (((bytes_found < nbytes) || (num_pages < 2))
557 && (last_page < (NUM_PAGES-1))
558 && (page_table[last_page+1].allocated == FREE_PAGE)) {
562 gc_assert(page_table[last_page].write_protected == 0);
565 region_size = (4096 - page_table[first_page].bytes_used)
566 + 4096*(last_page-first_page);
568 gc_assert(bytes_found == region_size);
572 "/last_page=%d bytes_found=%d num_pages=%d\n",
573 last_page, bytes_found, num_pages));
576 restart_page = last_page + 1;
577 } while ((restart_page < NUM_PAGES) && (bytes_found < nbytes));
579 /* Check for a failure. */
580 if ((restart_page >= NUM_PAGES) && (bytes_found < nbytes)) {
582 "Argh! gc_alloc_new_region() failed on restart_page, nbytes=%d.\n",
584 print_generation_stats(1);
590 "/gc_alloc_new_region() gen %d: %d bytes: pages %d to %d: addr=%x\n",
595 page_address(first_page)));
598 /* Set up the alloc_region. */
599 alloc_region->first_page = first_page;
600 alloc_region->last_page = last_page;
601 alloc_region->start_addr = page_table[first_page].bytes_used
602 + page_address(first_page);
603 alloc_region->free_pointer = alloc_region->start_addr;
604 alloc_region->end_addr = alloc_region->start_addr + bytes_found;
606 if (gencgc_zero_check) {
608 for (p = (int *)alloc_region->start_addr;
609 p < (int *)alloc_region->end_addr; p++) {
611 /* KLUDGE: It would be nice to use %lx and explicit casts
612 * (long) in code like this, so that it is less likely to
613 * break randomly when running on a machine with different
614 * word sizes. -- WHN 19991129 */
615 lose("The new region at %x is not zero.", p);
620 /* Set up the pages. */
622 /* The first page may have already been in use. */
623 if (page_table[first_page].bytes_used == 0) {
625 page_table[first_page].allocated = UNBOXED_PAGE;
627 page_table[first_page].allocated = BOXED_PAGE;
628 page_table[first_page].gen = gc_alloc_generation;
629 page_table[first_page].large_object = 0;
630 page_table[first_page].first_object_offset = 0;
634 gc_assert(page_table[first_page].allocated == UNBOXED_PAGE);
636 gc_assert(page_table[first_page].allocated == BOXED_PAGE);
637 gc_assert(page_table[first_page].gen == gc_alloc_generation);
638 gc_assert(page_table[first_page].large_object == 0);
640 for (i = first_page+1; i <= last_page; i++) {
642 page_table[i].allocated = UNBOXED_PAGE;
644 page_table[i].allocated = BOXED_PAGE;
645 page_table[i].gen = gc_alloc_generation;
646 page_table[i].large_object = 0;
647 /* This may not be necessary for unboxed regions (think it was
649 page_table[i].first_object_offset =
650 alloc_region->start_addr - page_address(i);
653 /* Bump up last_free_page. */
654 if (last_page+1 > last_free_page) {
655 last_free_page = last_page+1;
656 SetSymbolValue(ALLOCATION_POINTER,
657 (lispobj)(((char *)heap_base) + last_free_page*4096));
658 if (last_page+1 > last_used_page)
659 last_used_page = last_page+1;
663 /* If the record_new_objects flag is 2 then all new regions created
666 * If it's 1 then then it is only recorded if the first page of the
667 * current region is <= new_areas_ignore_page. This helps avoid
668 * unnecessary recording when doing full scavenge pass.
670 * The new_object structure holds the page, byte offset, and size of
671 * new regions of objects. Each new area is placed in the array of
672 * these structures pointer to by new_areas. new_areas_index holds the
673 * offset into new_areas.
675 * If new_area overflows NUM_NEW_AREAS then it stops adding them. The
676 * later code must detect this and handle it, probably by doing a full
677 * scavenge of a generation. */
678 #define NUM_NEW_AREAS 512
679 static int record_new_objects = 0;
680 static int new_areas_ignore_page;
686 static struct new_area (*new_areas)[];
687 static int new_areas_index;
690 /* Add a new area to new_areas. */
692 add_new_area(int first_page, int offset, int size)
694 unsigned new_area_start,c;
697 /* Ignore if full. */
698 if (new_areas_index >= NUM_NEW_AREAS)
701 switch (record_new_objects) {
705 if (first_page > new_areas_ignore_page)
714 new_area_start = 4096*first_page + offset;
716 /* Search backwards for a prior area that this follows from. If
717 found this will save adding a new area. */
718 for (i = new_areas_index-1, c = 0; (i >= 0) && (c < 8); i--, c++) {
720 4096*((*new_areas)[i].page)
721 + (*new_areas)[i].offset
722 + (*new_areas)[i].size;
724 "/add_new_area S1 %d %d %d %d\n",
725 i, c, new_area_start, area_end));*/
726 if (new_area_start == area_end) {
728 "/adding to [%d] %d %d %d with %d %d %d:\n",
730 (*new_areas)[i].page,
731 (*new_areas)[i].offset,
732 (*new_areas)[i].size,
736 (*new_areas)[i].size += size;
740 /*FSHOW((stderr, "/add_new_area S1 %d %d %d\n", i, c, new_area_start));*/
742 (*new_areas)[new_areas_index].page = first_page;
743 (*new_areas)[new_areas_index].offset = offset;
744 (*new_areas)[new_areas_index].size = size;
746 "/new_area %d page %d offset %d size %d\n",
747 new_areas_index, first_page, offset, size));*/
750 /* Note the max new_areas used. */
751 if (new_areas_index > max_new_areas)
752 max_new_areas = new_areas_index;
755 /* Update the tables for the alloc_region. The region maybe added to
758 * When done the alloc_region is set up so that the next quick alloc
759 * will fail safely and thus a new region will be allocated. Further
760 * it is safe to try to re-update the page table of this reset
763 gc_alloc_update_page_tables(int unboxed, struct alloc_region *alloc_region)
769 int orig_first_page_bytes_used;
775 "/gc_alloc_update_page_tables() to gen %d:\n",
776 gc_alloc_generation));
779 first_page = alloc_region->first_page;
781 /* Catch an unused alloc_region. */
782 if ((first_page == 0) && (alloc_region->last_page == -1))
785 next_page = first_page+1;
787 /* Skip if no bytes were allocated. */
788 if (alloc_region->free_pointer != alloc_region->start_addr) {
789 orig_first_page_bytes_used = page_table[first_page].bytes_used;
791 gc_assert(alloc_region->start_addr == (page_address(first_page) + page_table[first_page].bytes_used));
793 /* All the pages used need to be updated */
795 /* Update the first page. */
797 /* If the page was free then set up the gen, and
798 * first_object_offset. */
799 if (page_table[first_page].bytes_used == 0)
800 gc_assert(page_table[first_page].first_object_offset == 0);
803 gc_assert(page_table[first_page].allocated == UNBOXED_PAGE);
805 gc_assert(page_table[first_page].allocated == BOXED_PAGE);
806 gc_assert(page_table[first_page].gen == gc_alloc_generation);
807 gc_assert(page_table[first_page].large_object == 0);
811 /* Calculate the number of bytes used in this page. This is not
812 * always the number of new bytes, unless it was free. */
814 if ((bytes_used = (alloc_region->free_pointer - page_address(first_page)))>4096) {
818 page_table[first_page].bytes_used = bytes_used;
819 byte_cnt += bytes_used;
822 /* All the rest of the pages should be free. We need to set their
823 * first_object_offset pointer to the start of the region, and set
827 gc_assert(page_table[next_page].allocated == UNBOXED_PAGE);
829 gc_assert(page_table[next_page].allocated == BOXED_PAGE);
830 gc_assert(page_table[next_page].bytes_used == 0);
831 gc_assert(page_table[next_page].gen == gc_alloc_generation);
832 gc_assert(page_table[next_page].large_object == 0);
834 gc_assert(page_table[next_page].first_object_offset ==
835 alloc_region->start_addr - page_address(next_page));
837 /* Calculate the number of bytes used in this page. */
839 if ((bytes_used = (alloc_region->free_pointer
840 - page_address(next_page)))>4096) {
844 page_table[next_page].bytes_used = bytes_used;
845 byte_cnt += bytes_used;
850 region_size = alloc_region->free_pointer - alloc_region->start_addr;
851 bytes_allocated += region_size;
852 generations[gc_alloc_generation].bytes_allocated += region_size;
854 gc_assert((byte_cnt- orig_first_page_bytes_used) == region_size);
856 /* Set the generations alloc restart page to the last page of
859 generations[gc_alloc_generation].alloc_unboxed_start_page =
862 generations[gc_alloc_generation].alloc_start_page = next_page-1;
864 /* Add the region to the new_areas if requested. */
866 add_new_area(first_page,orig_first_page_bytes_used, region_size);
870 "/gc_alloc_update_page_tables update %d bytes to gen %d\n",
872 gc_alloc_generation));
875 /* There are no bytes allocated. Unallocate the first_page if
876 * there are 0 bytes_used. */
877 if (page_table[first_page].bytes_used == 0)
878 page_table[first_page].allocated = FREE_PAGE;
881 /* Unallocate any unused pages. */
882 while (next_page <= alloc_region->last_page) {
883 gc_assert(page_table[next_page].bytes_used == 0);
884 page_table[next_page].allocated = FREE_PAGE;
888 /* Reset the alloc_region. */
889 alloc_region->first_page = 0;
890 alloc_region->last_page = -1;
891 alloc_region->start_addr = page_address(0);
892 alloc_region->free_pointer = page_address(0);
893 alloc_region->end_addr = page_address(0);
896 static inline void *gc_quick_alloc(int nbytes);
898 /* Allocate a possibly large object. */
900 gc_alloc_large(int nbytes, int unboxed, struct alloc_region *alloc_region)
908 int orig_first_page_bytes_used;
913 int large = (nbytes >= large_object_size);
917 FSHOW((stderr, "/alloc_large %d\n", nbytes));
922 "/gc_alloc_large() for %d bytes from gen %d\n",
923 nbytes, gc_alloc_generation));
926 /* If the object is small, and there is room in the current region
927 then allocation it in the current region. */
929 && ((alloc_region->end_addr-alloc_region->free_pointer) >= nbytes))
930 return gc_quick_alloc(nbytes);
932 /* Search for a contiguous free region of at least nbytes. If it's a
933 large object then align it on a page boundary by searching for a
936 /* To allow the allocation of small objects without the danger of
937 using a page in the current boxed region, the search starts after
938 the current boxed free region. XX could probably keep a page
939 index ahead of the current region and bumped up here to save a
940 lot of re-scanning. */
943 generations[gc_alloc_generation].alloc_large_unboxed_start_page;
945 restart_page = generations[gc_alloc_generation].alloc_large_start_page;
947 if (restart_page <= alloc_region->last_page) {
948 restart_page = alloc_region->last_page+1;
952 first_page = restart_page;
955 while ((first_page < NUM_PAGES)
956 && (page_table[first_page].allocated != FREE_PAGE))
959 /* FIXME: This looks extremely similar, perhaps identical,
960 * to code in gc_alloc_new_region(). It should be shared
962 while ((first_page < NUM_PAGES)
963 && (page_table[first_page].allocated != FREE_PAGE)
965 (page_table[first_page].allocated != UNBOXED_PAGE))
967 (page_table[first_page].allocated != BOXED_PAGE))
968 || (page_table[first_page].large_object != 0)
969 || (page_table[first_page].gen != gc_alloc_generation)
970 || (page_table[first_page].bytes_used >= (4096-32))
971 || (page_table[first_page].write_protected != 0)
972 || (page_table[first_page].dont_move != 0)))
975 if (first_page >= NUM_PAGES) {
977 "Argh! gc_alloc_large failed (first_page), nbytes=%d.\n",
979 print_generation_stats(1);
983 gc_assert(page_table[first_page].write_protected == 0);
987 "/first_page=%d bytes_used=%d\n",
988 first_page, page_table[first_page].bytes_used));
991 last_page = first_page;
992 bytes_found = 4096 - page_table[first_page].bytes_used;
994 while ((bytes_found < nbytes)
995 && (last_page < (NUM_PAGES-1))
996 && (page_table[last_page+1].allocated == FREE_PAGE)) {
1000 gc_assert(page_table[last_page].write_protected == 0);
1003 region_size = (4096 - page_table[first_page].bytes_used)
1004 + 4096*(last_page-first_page);
1006 gc_assert(bytes_found == region_size);
1010 "/last_page=%d bytes_found=%d num_pages=%d\n",
1011 last_page, bytes_found, num_pages));
1014 restart_page = last_page + 1;
1015 } while ((restart_page < NUM_PAGES) && (bytes_found < nbytes));
1017 /* Check for a failure */
1018 if ((restart_page >= NUM_PAGES) && (bytes_found < nbytes)) {
1020 "Argh! gc_alloc_large failed (restart_page), nbytes=%d.\n",
1022 print_generation_stats(1);
1029 "/gc_alloc_large() gen %d: %d of %d bytes: from pages %d to %d: addr=%x\n",
1030 gc_alloc_generation,
1035 page_address(first_page)));
1038 gc_assert(first_page > alloc_region->last_page);
1040 generations[gc_alloc_generation].alloc_large_unboxed_start_page =
1043 generations[gc_alloc_generation].alloc_large_start_page = last_page;
1045 /* Set up the pages. */
1046 orig_first_page_bytes_used = page_table[first_page].bytes_used;
1048 /* If the first page was free then set up the gen, and
1049 * first_object_offset. */
1050 if (page_table[first_page].bytes_used == 0) {
1052 page_table[first_page].allocated = UNBOXED_PAGE;
1054 page_table[first_page].allocated = BOXED_PAGE;
1055 page_table[first_page].gen = gc_alloc_generation;
1056 page_table[first_page].first_object_offset = 0;
1057 page_table[first_page].large_object = large;
1061 gc_assert(page_table[first_page].allocated == UNBOXED_PAGE);
1063 gc_assert(page_table[first_page].allocated == BOXED_PAGE);
1064 gc_assert(page_table[first_page].gen == gc_alloc_generation);
1065 gc_assert(page_table[first_page].large_object == large);
1069 /* Calc. the number of bytes used in this page. This is not
1070 * always the number of new bytes, unless it was free. */
1072 if ((bytes_used = nbytes+orig_first_page_bytes_used) > 4096) {
1076 page_table[first_page].bytes_used = bytes_used;
1077 byte_cnt += bytes_used;
1079 next_page = first_page+1;
1081 /* All the rest of the pages should be free. We need to set their
1082 * first_object_offset pointer to the start of the region, and
1083 * set the bytes_used. */
1085 gc_assert(page_table[next_page].allocated == FREE_PAGE);
1086 gc_assert(page_table[next_page].bytes_used == 0);
1088 page_table[next_page].allocated = UNBOXED_PAGE;
1090 page_table[next_page].allocated = BOXED_PAGE;
1091 page_table[next_page].gen = gc_alloc_generation;
1092 page_table[next_page].large_object = large;
1094 page_table[next_page].first_object_offset =
1095 orig_first_page_bytes_used - 4096*(next_page-first_page);
1097 /* Calculate the number of bytes used in this page. */
1099 if ((bytes_used=(nbytes+orig_first_page_bytes_used)-byte_cnt) > 4096) {
1103 page_table[next_page].bytes_used = bytes_used;
1104 byte_cnt += bytes_used;
1109 gc_assert((byte_cnt-orig_first_page_bytes_used) == nbytes);
1111 bytes_allocated += nbytes;
1112 generations[gc_alloc_generation].bytes_allocated += nbytes;
1114 /* Add the region to the new_areas if requested. */
1116 add_new_area(first_page,orig_first_page_bytes_used,nbytes);
1118 /* Bump up last_free_page */
1119 if (last_page+1 > last_free_page) {
1120 last_free_page = last_page+1;
1121 SetSymbolValue(ALLOCATION_POINTER,
1122 (lispobj)(((char *)heap_base) + last_free_page*4096));
1123 if (last_page+1 > last_used_page)
1124 last_used_page = last_page+1;
1127 return((void *)(page_address(first_page)+orig_first_page_bytes_used));
1130 /* Allocate bytes from the boxed_region. First checks whether there is
1131 * room. If not then call gc_alloc_new_region() to find a new region
1132 * with enough space. Return a pointer to the start of the region. */
1134 gc_alloc(int nbytes)
1136 void *new_free_pointer;
1138 /* FSHOW((stderr, "/gc_alloc %d\n", nbytes)); */
1140 /* Check whether there is room in the current alloc region. */
1141 new_free_pointer = boxed_region.free_pointer + nbytes;
1143 if (new_free_pointer <= boxed_region.end_addr) {
1144 /* If so then allocate from the current alloc region. */
1145 void *new_obj = boxed_region.free_pointer;
1146 boxed_region.free_pointer = new_free_pointer;
1148 /* Check whether the alloc region is almost empty. */
1149 if ((boxed_region.end_addr - boxed_region.free_pointer) <= 32) {
1150 /* If so finished with the current region. */
1151 gc_alloc_update_page_tables(0, &boxed_region);
1152 /* Set up a new region. */
1153 gc_alloc_new_region(32, 0, &boxed_region);
1155 return((void *)new_obj);
1158 /* Else not enough free space in the current region. */
1160 /* If there some room left in the current region, enough to be worth
1161 * saving, then allocate a large object. */
1162 /* FIXME: "32" should be a named parameter. */
1163 if ((boxed_region.end_addr-boxed_region.free_pointer) > 32)
1164 return gc_alloc_large(nbytes, 0, &boxed_region);
1166 /* Else find a new region. */
1168 /* Finished with the current region. */
1169 gc_alloc_update_page_tables(0, &boxed_region);
1171 /* Set up a new region. */
1172 gc_alloc_new_region(nbytes, 0, &boxed_region);
1174 /* Should now be enough room. */
1176 /* Check whether there is room in the current region. */
1177 new_free_pointer = boxed_region.free_pointer + nbytes;
1179 if (new_free_pointer <= boxed_region.end_addr) {
1180 /* If so then allocate from the current region. */
1181 void *new_obj = boxed_region.free_pointer;
1182 boxed_region.free_pointer = new_free_pointer;
1184 /* Check whether the current region is almost empty. */
1185 if ((boxed_region.end_addr - boxed_region.free_pointer) <= 32) {
1186 /* If so find, finished with the current region. */
1187 gc_alloc_update_page_tables(0, &boxed_region);
1189 /* Set up a new region. */
1190 gc_alloc_new_region(32, 0, &boxed_region);
1193 return((void *)new_obj);
1196 /* shouldn't happen */
1198 return((void *) NIL); /* dummy value: return something ... */
1201 /* Allocate space from the boxed_region. If there is not enough free
1202 * space then call gc_alloc to do the job. A pointer to the start of
1203 * the region is returned. */
1204 static inline void *
1205 gc_quick_alloc(int nbytes)
1207 void *new_free_pointer;
1209 /* Check whether there is room in the current region. */
1210 new_free_pointer = boxed_region.free_pointer + nbytes;
1212 if (new_free_pointer <= boxed_region.end_addr) {
1213 /* Allocate from the current region. */
1214 void *new_obj = boxed_region.free_pointer;
1215 boxed_region.free_pointer = new_free_pointer;
1216 return((void *)new_obj);
1218 /* Let full gc_alloc() handle it. */
1219 return gc_alloc(nbytes);
1223 /* Allocate space for the boxed object. If it is a large object then
1224 * do a large alloc else allocate from the current region. If there is
1225 * not enough free space then call gc_alloc() to do the job. A pointer
1226 * to the start of the region is returned. */
1227 static inline void *
1228 gc_quick_alloc_large(int nbytes)
1230 void *new_free_pointer;
1232 if (nbytes >= large_object_size)
1233 return gc_alloc_large(nbytes, 0, &boxed_region);
1235 /* Check whether there is room in the current region. */
1236 new_free_pointer = boxed_region.free_pointer + nbytes;
1238 if (new_free_pointer <= boxed_region.end_addr) {
1239 /* If so then allocate from the current region. */
1240 void *new_obj = boxed_region.free_pointer;
1241 boxed_region.free_pointer = new_free_pointer;
1242 return((void *)new_obj);
1244 /* Let full gc_alloc() handle it. */
1245 return gc_alloc(nbytes);
1250 gc_alloc_unboxed(int nbytes)
1252 void *new_free_pointer;
1255 FSHOW((stderr, "/gc_alloc_unboxed() %d\n", nbytes));
1258 /* Check whether there is room in the current region. */
1259 new_free_pointer = unboxed_region.free_pointer + nbytes;
1261 if (new_free_pointer <= unboxed_region.end_addr) {
1262 /* If so then allocate from the current region. */
1263 void *new_obj = unboxed_region.free_pointer;
1264 unboxed_region.free_pointer = new_free_pointer;
1266 /* Check whether the current region is almost empty. */
1267 if ((unboxed_region.end_addr - unboxed_region.free_pointer) <= 32) {
1268 /* If so finished with the current region. */
1269 gc_alloc_update_page_tables(1, &unboxed_region);
1271 /* Set up a new region. */
1272 gc_alloc_new_region(32, 1, &unboxed_region);
1275 return((void *)new_obj);
1278 /* Else not enough free space in the current region. */
1280 /* If there is a bit of room left in the current region then
1281 allocate a large object. */
1282 if ((unboxed_region.end_addr-unboxed_region.free_pointer) > 32)
1283 return gc_alloc_large(nbytes,1,&unboxed_region);
1285 /* Else find a new region. */
1287 /* Finished with the current region. */
1288 gc_alloc_update_page_tables(1, &unboxed_region);
1290 /* Set up a new region. */
1291 gc_alloc_new_region(nbytes, 1, &unboxed_region);
1293 /* (There should now be enough room.) */
1295 /* Check whether there is room in the current region. */
1296 new_free_pointer = unboxed_region.free_pointer + nbytes;
1298 if (new_free_pointer <= unboxed_region.end_addr) {
1299 /* If so then allocate from the current region. */
1300 void *new_obj = unboxed_region.free_pointer;
1301 unboxed_region.free_pointer = new_free_pointer;
1303 /* Check whether the current region is almost empty. */
1304 if ((unboxed_region.end_addr - unboxed_region.free_pointer) <= 32) {
1305 /* If so find, finished with the current region. */
1306 gc_alloc_update_page_tables(1, &unboxed_region);
1308 /* Set up a new region. */
1309 gc_alloc_new_region(32, 1, &unboxed_region);
1312 return((void *)new_obj);
1315 /* shouldn't happen? */
1317 return((void *) NIL); /* dummy value: return something ... */
1320 static inline void *
1321 gc_quick_alloc_unboxed(int nbytes)
1323 void *new_free_pointer;
1325 /* Check whether there is room in the current region. */
1326 new_free_pointer = unboxed_region.free_pointer + nbytes;
1328 if (new_free_pointer <= unboxed_region.end_addr) {
1329 /* If so then allocate from the current region. */
1330 void *new_obj = unboxed_region.free_pointer;
1331 unboxed_region.free_pointer = new_free_pointer;
1333 return((void *)new_obj);
1335 /* Let general gc_alloc_unboxed() handle it. */
1336 return gc_alloc_unboxed(nbytes);
1340 /* Allocate space for the object. If it is a large object then do a
1341 * large alloc else allocate from the current region. If there is not
1342 * enough free space then call general gc_alloc_unboxed() to do the job.
1344 * A pointer to the start of the region is returned. */
1345 static inline void *
1346 gc_quick_alloc_large_unboxed(int nbytes)
1348 void *new_free_pointer;
1350 if (nbytes >= large_object_size)
1351 return gc_alloc_large(nbytes,1,&unboxed_region);
1353 /* Check whether there is room in the current region. */
1354 new_free_pointer = unboxed_region.free_pointer + nbytes;
1355 if (new_free_pointer <= unboxed_region.end_addr) {
1356 /* Allocate from the current region. */
1357 void *new_obj = unboxed_region.free_pointer;
1358 unboxed_region.free_pointer = new_free_pointer;
1359 return((void *)new_obj);
1361 /* Let full gc_alloc() handle it. */
1362 return gc_alloc_unboxed(nbytes);
1367 * scavenging/transporting routines derived from gc.c in CMU CL ca. 18b
1370 static int (*scavtab[256])(lispobj *where, lispobj object);
1371 static lispobj (*transother[256])(lispobj object);
1372 static int (*sizetab[256])(lispobj *where);
1374 static struct weak_pointer *weak_pointers;
1376 #define CEILING(x,y) (((x) + ((y) - 1)) & (~((y) - 1)))
1382 static inline boolean
1383 from_space_p(lispobj obj)
1385 int page_index=(void*)obj - heap_base;
1386 return ((page_index >= 0)
1387 && ((page_index = ((unsigned int)page_index)/4096) < NUM_PAGES)
1388 && (page_table[page_index].gen == from_space));
1391 static inline boolean
1392 new_space_p(lispobj obj)
1394 int page_index = (void*)obj - heap_base;
1395 return ((page_index >= 0)
1396 && ((page_index = ((unsigned int)page_index)/4096) < NUM_PAGES)
1397 && (page_table[page_index].gen == new_space));
1404 /* to copy a boxed object */
1405 static inline lispobj
1406 copy_object(lispobj object, int nwords)
1410 lispobj *source, *dest;
1412 gc_assert(is_lisp_pointer(object));
1413 gc_assert(from_space_p(object));
1414 gc_assert((nwords & 0x01) == 0);
1416 /* Get tag of object. */
1417 tag = LowtagOf(object);
1419 /* Allocate space. */
1420 new = gc_quick_alloc(nwords*4);
1423 source = (lispobj *) native_pointer(object);
1425 /* Copy the object. */
1426 while (nwords > 0) {
1427 dest[0] = source[0];
1428 dest[1] = source[1];
1434 /* Return Lisp pointer of new object. */
1435 return ((lispobj) new) | tag;
1438 /* to copy a large boxed object. If the object is in a large object
1439 * region then it is simply promoted, else it is copied. If it's large
1440 * enough then it's copied to a large object region.
1442 * Vectors may have shrunk. If the object is not copied the space
1443 * needs to be reclaimed, and the page_tables corrected. */
1445 copy_large_object(lispobj object, int nwords)
1449 lispobj *source, *dest;
1452 gc_assert(is_lisp_pointer(object));
1453 gc_assert(from_space_p(object));
1454 gc_assert((nwords & 0x01) == 0);
1456 if ((nwords > 1024*1024) && gencgc_verbose) {
1457 FSHOW((stderr, "/copy_large_object: %d bytes\n", nwords*4));
1460 /* Check whether it's a large object. */
1461 first_page = find_page_index((void *)object);
1462 gc_assert(first_page >= 0);
1464 if (page_table[first_page].large_object) {
1466 /* Promote the object. */
1468 int remaining_bytes;
1473 /* Note: Any page write-protection must be removed, else a
1474 * later scavenge_newspace may incorrectly not scavenge these
1475 * pages. This would not be necessary if they are added to the
1476 * new areas, but let's do it for them all (they'll probably
1477 * be written anyway?). */
1479 gc_assert(page_table[first_page].first_object_offset == 0);
1481 next_page = first_page;
1482 remaining_bytes = nwords*4;
1483 while (remaining_bytes > 4096) {
1484 gc_assert(page_table[next_page].gen == from_space);
1485 gc_assert(page_table[next_page].allocated == BOXED_PAGE);
1486 gc_assert(page_table[next_page].large_object);
1487 gc_assert(page_table[next_page].first_object_offset==
1488 -4096*(next_page-first_page));
1489 gc_assert(page_table[next_page].bytes_used == 4096);
1491 page_table[next_page].gen = new_space;
1493 /* Remove any write-protection. We should be able to rely
1494 * on the write-protect flag to avoid redundant calls. */
1495 if (page_table[next_page].write_protected) {
1496 os_protect(page_address(next_page), 4096, OS_VM_PROT_ALL);
1497 page_table[next_page].write_protected = 0;
1499 remaining_bytes -= 4096;
1503 /* Now only one page remains, but the object may have shrunk
1504 * so there may be more unused pages which will be freed. */
1506 /* The object may have shrunk but shouldn't have grown. */
1507 gc_assert(page_table[next_page].bytes_used >= remaining_bytes);
1509 page_table[next_page].gen = new_space;
1510 gc_assert(page_table[next_page].allocated = BOXED_PAGE);
1512 /* Adjust the bytes_used. */
1513 old_bytes_used = page_table[next_page].bytes_used;
1514 page_table[next_page].bytes_used = remaining_bytes;
1516 bytes_freed = old_bytes_used - remaining_bytes;
1518 /* Free any remaining pages; needs care. */
1520 while ((old_bytes_used == 4096) &&
1521 (page_table[next_page].gen == from_space) &&
1522 (page_table[next_page].allocated == BOXED_PAGE) &&
1523 page_table[next_page].large_object &&
1524 (page_table[next_page].first_object_offset ==
1525 -(next_page - first_page)*4096)) {
1526 /* Checks out OK, free the page. Don't need to both zeroing
1527 * pages as this should have been done before shrinking the
1528 * object. These pages shouldn't be write-protected as they
1529 * should be zero filled. */
1530 gc_assert(page_table[next_page].write_protected == 0);
1532 old_bytes_used = page_table[next_page].bytes_used;
1533 page_table[next_page].allocated = FREE_PAGE;
1534 page_table[next_page].bytes_used = 0;
1535 bytes_freed += old_bytes_used;
1539 if ((bytes_freed > 0) && gencgc_verbose)
1540 FSHOW((stderr, "/copy_large_boxed bytes_freed=%d\n", bytes_freed));
1542 generations[from_space].bytes_allocated -= 4*nwords + bytes_freed;
1543 generations[new_space].bytes_allocated += 4*nwords;
1544 bytes_allocated -= bytes_freed;
1546 /* Add the region to the new_areas if requested. */
1547 add_new_area(first_page,0,nwords*4);
1551 /* Get tag of object. */
1552 tag = LowtagOf(object);
1554 /* Allocate space. */
1555 new = gc_quick_alloc_large(nwords*4);
1558 source = (lispobj *) native_pointer(object);
1560 /* Copy the object. */
1561 while (nwords > 0) {
1562 dest[0] = source[0];
1563 dest[1] = source[1];
1569 /* Return Lisp pointer of new object. */
1570 return ((lispobj) new) | tag;
1574 /* to copy unboxed objects */
1575 static inline lispobj
1576 copy_unboxed_object(lispobj object, int nwords)
1580 lispobj *source, *dest;
1582 gc_assert(is_lisp_pointer(object));
1583 gc_assert(from_space_p(object));
1584 gc_assert((nwords & 0x01) == 0);
1586 /* Get tag of object. */
1587 tag = LowtagOf(object);
1589 /* Allocate space. */
1590 new = gc_quick_alloc_unboxed(nwords*4);
1593 source = (lispobj *) native_pointer(object);
1595 /* Copy the object. */
1596 while (nwords > 0) {
1597 dest[0] = source[0];
1598 dest[1] = source[1];
1604 /* Return Lisp pointer of new object. */
1605 return ((lispobj) new) | tag;
1608 /* to copy large unboxed objects
1610 * If the object is in a large object region then it is simply
1611 * promoted, else it is copied. If it's large enough then it's copied
1612 * to a large object region.
1614 * Bignums and vectors may have shrunk. If the object is not copied
1615 * the space needs to be reclaimed, and the page_tables corrected.
1617 * KLUDGE: There's a lot of cut-and-paste duplication between this
1618 * function and copy_large_object(..). -- WHN 20000619 */
1620 copy_large_unboxed_object(lispobj object, int nwords)
1624 lispobj *source, *dest;
1627 gc_assert(is_lisp_pointer(object));
1628 gc_assert(from_space_p(object));
1629 gc_assert((nwords & 0x01) == 0);
1631 if ((nwords > 1024*1024) && gencgc_verbose)
1632 FSHOW((stderr, "/copy_large_unboxed_object: %d bytes\n", nwords*4));
1634 /* Check whether it's a large object. */
1635 first_page = find_page_index((void *)object);
1636 gc_assert(first_page >= 0);
1638 if (page_table[first_page].large_object) {
1639 /* Promote the object. Note: Unboxed objects may have been
1640 * allocated to a BOXED region so it may be necessary to
1641 * change the region to UNBOXED. */
1642 int remaining_bytes;
1647 gc_assert(page_table[first_page].first_object_offset == 0);
1649 next_page = first_page;
1650 remaining_bytes = nwords*4;
1651 while (remaining_bytes > 4096) {
1652 gc_assert(page_table[next_page].gen == from_space);
1653 gc_assert((page_table[next_page].allocated == UNBOXED_PAGE)
1654 || (page_table[next_page].allocated == BOXED_PAGE));
1655 gc_assert(page_table[next_page].large_object);
1656 gc_assert(page_table[next_page].first_object_offset==
1657 -4096*(next_page-first_page));
1658 gc_assert(page_table[next_page].bytes_used == 4096);
1660 page_table[next_page].gen = new_space;
1661 page_table[next_page].allocated = UNBOXED_PAGE;
1662 remaining_bytes -= 4096;
1666 /* Now only one page remains, but the object may have shrunk so
1667 * there may be more unused pages which will be freed. */
1669 /* Object may have shrunk but shouldn't have grown - check. */
1670 gc_assert(page_table[next_page].bytes_used >= remaining_bytes);
1672 page_table[next_page].gen = new_space;
1673 page_table[next_page].allocated = UNBOXED_PAGE;
1675 /* Adjust the bytes_used. */
1676 old_bytes_used = page_table[next_page].bytes_used;
1677 page_table[next_page].bytes_used = remaining_bytes;
1679 bytes_freed = old_bytes_used - remaining_bytes;
1681 /* Free any remaining pages; needs care. */
1683 while ((old_bytes_used == 4096) &&
1684 (page_table[next_page].gen == from_space) &&
1685 ((page_table[next_page].allocated == UNBOXED_PAGE)
1686 || (page_table[next_page].allocated == BOXED_PAGE)) &&
1687 page_table[next_page].large_object &&
1688 (page_table[next_page].first_object_offset ==
1689 -(next_page - first_page)*4096)) {
1690 /* Checks out OK, free the page. Don't need to both zeroing
1691 * pages as this should have been done before shrinking the
1692 * object. These pages shouldn't be write-protected, even if
1693 * boxed they should be zero filled. */
1694 gc_assert(page_table[next_page].write_protected == 0);
1696 old_bytes_used = page_table[next_page].bytes_used;
1697 page_table[next_page].allocated = FREE_PAGE;
1698 page_table[next_page].bytes_used = 0;
1699 bytes_freed += old_bytes_used;
1703 if ((bytes_freed > 0) && gencgc_verbose)
1705 "/copy_large_unboxed bytes_freed=%d\n",
1708 generations[from_space].bytes_allocated -= 4*nwords + bytes_freed;
1709 generations[new_space].bytes_allocated += 4*nwords;
1710 bytes_allocated -= bytes_freed;
1715 /* Get tag of object. */
1716 tag = LowtagOf(object);
1718 /* Allocate space. */
1719 new = gc_quick_alloc_large_unboxed(nwords*4);
1722 source = (lispobj *) native_pointer(object);
1724 /* Copy the object. */
1725 while (nwords > 0) {
1726 dest[0] = source[0];
1727 dest[1] = source[1];
1733 /* Return Lisp pointer of new object. */
1734 return ((lispobj) new) | tag;
1742 /* FIXME: Most calls end up going to some trouble to compute an
1743 * 'n_words' value for this function. The system might be a little
1744 * simpler if this function used an 'end' parameter instead. */
1746 scavenge(lispobj *start, long n_words)
1748 lispobj *end = start + n_words;
1749 lispobj *object_ptr;
1750 int n_words_scavenged;
1752 for (object_ptr = start;
1754 object_ptr += n_words_scavenged) {
1756 lispobj object = *object_ptr;
1758 gc_assert(object != 0x01); /* not a forwarding pointer */
1760 if (is_lisp_pointer(object)) {
1761 if (from_space_p(object)) {
1762 /* It currently points to old space. Check for a
1763 * forwarding pointer. */
1764 lispobj *ptr = (lispobj *)native_pointer(object);
1765 lispobj first_word = *ptr;
1766 if (first_word == 0x01) {
1767 /* Yes, there's a forwarding pointer. */
1768 *object_ptr = ptr[1];
1769 n_words_scavenged = 1;
1771 /* Scavenge that pointer. */
1773 (scavtab[TypeOf(object)])(object_ptr, object);
1776 /* It points somewhere other than oldspace. Leave it
1778 n_words_scavenged = 1;
1780 } else if ((object & 3) == 0) {
1781 /* It's a fixnum: really easy.. */
1782 n_words_scavenged = 1;
1784 /* It's some sort of header object or another. */
1786 (scavtab[TypeOf(object)])(object_ptr, object);
1789 gc_assert(object_ptr == end);
1793 * code and code-related objects
1796 #define RAW_ADDR_OFFSET (6*sizeof(lispobj) - type_FunctionPointer)
1798 static lispobj trans_function_header(lispobj object);
1799 static lispobj trans_boxed(lispobj object);
1802 scav_function_pointer(lispobj *where, lispobj object)
1804 lispobj *first_pointer;
1807 gc_assert(is_lisp_pointer(object));
1809 /* Object is a pointer into from space - no a FP. */
1810 first_pointer = (lispobj *) native_pointer(object);
1812 /* must transport object -- object may point to either a function
1813 * header, a closure function header, or to a closure header. */
1815 switch (TypeOf(*first_pointer)) {
1816 case type_FunctionHeader:
1817 case type_ClosureFunctionHeader:
1818 copy = trans_function_header(object);
1821 copy = trans_boxed(object);
1825 if (copy != object) {
1826 /* Set forwarding pointer */
1827 first_pointer[0] = 0x01;
1828 first_pointer[1] = copy;
1831 gc_assert(is_lisp_pointer(copy));
1832 gc_assert(!from_space_p(copy));
1839 /* Scan a x86 compiled code object, looking for possible fixups that
1840 * have been missed after a move.
1842 * Two types of fixups are needed:
1843 * 1. Absolute fixups to within the code object.
1844 * 2. Relative fixups to outside the code object.
1846 * Currently only absolute fixups to the constant vector, or to the
1847 * code area are checked. */
1849 sniff_code_object(struct code *code, unsigned displacement)
1851 int nheader_words, ncode_words, nwords;
1853 void *constants_start_addr, *constants_end_addr;
1854 void *code_start_addr, *code_end_addr;
1855 int fixup_found = 0;
1857 if (!check_code_fixups)
1860 ncode_words = fixnum_value(code->code_size);
1861 nheader_words = HeaderValue(*(lispobj *)code);
1862 nwords = ncode_words + nheader_words;
1864 constants_start_addr = (void *)code + 5*4;
1865 constants_end_addr = (void *)code + nheader_words*4;
1866 code_start_addr = (void *)code + nheader_words*4;
1867 code_end_addr = (void *)code + nwords*4;
1869 /* Work through the unboxed code. */
1870 for (p = code_start_addr; p < code_end_addr; p++) {
1871 void *data = *(void **)p;
1872 unsigned d1 = *((unsigned char *)p - 1);
1873 unsigned d2 = *((unsigned char *)p - 2);
1874 unsigned d3 = *((unsigned char *)p - 3);
1875 unsigned d4 = *((unsigned char *)p - 4);
1877 unsigned d5 = *((unsigned char *)p - 5);
1878 unsigned d6 = *((unsigned char *)p - 6);
1881 /* Check for code references. */
1882 /* Check for a 32 bit word that looks like an absolute
1883 reference to within the code adea of the code object. */
1884 if ((data >= (code_start_addr-displacement))
1885 && (data < (code_end_addr-displacement))) {
1886 /* function header */
1888 && (((unsigned)p - 4 - 4*HeaderValue(*((unsigned *)p-1))) == (unsigned)code)) {
1889 /* Skip the function header */
1893 /* the case of PUSH imm32 */
1897 "/code ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1898 p, d6, d5, d4, d3, d2, d1, data));
1899 FSHOW((stderr, "/PUSH $0x%.8x\n", data));
1901 /* the case of MOV [reg-8],imm32 */
1903 && (d2==0x40 || d2==0x41 || d2==0x42 || d2==0x43
1904 || d2==0x45 || d2==0x46 || d2==0x47)
1908 "/code ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1909 p, d6, d5, d4, d3, d2, d1, data));
1910 FSHOW((stderr, "/MOV [reg-8],$0x%.8x\n", data));
1912 /* the case of LEA reg,[disp32] */
1913 if ((d2 == 0x8d) && ((d1 & 0xc7) == 5)) {
1916 "/code ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1917 p, d6, d5, d4, d3, d2, d1, data));
1918 FSHOW((stderr,"/LEA reg,[$0x%.8x]\n", data));
1922 /* Check for constant references. */
1923 /* Check for a 32 bit word that looks like an absolute
1924 reference to within the constant vector. Constant references
1926 if ((data >= (constants_start_addr-displacement))
1927 && (data < (constants_end_addr-displacement))
1928 && (((unsigned)data & 0x3) == 0)) {
1933 "/abs const ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1934 p, d6, d5, d4, d3, d2, d1, data));
1935 FSHOW((stderr,"/MOV eax,0x%.8x\n", data));
1938 /* the case of MOV m32,EAX */
1942 "/abs const ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1943 p, d6, d5, d4, d3, d2, d1, data));
1944 FSHOW((stderr, "/MOV 0x%.8x,eax\n", data));
1947 /* the case of CMP m32,imm32 */
1948 if ((d1 == 0x3d) && (d2 == 0x81)) {
1951 "/abs const ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1952 p, d6, d5, d4, d3, d2, d1, data));
1954 FSHOW((stderr, "/CMP 0x%.8x,immed32\n", data));
1957 /* Check for a mod=00, r/m=101 byte. */
1958 if ((d1 & 0xc7) == 5) {
1963 "/abs const ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1964 p, d6, d5, d4, d3, d2, d1, data));
1965 FSHOW((stderr,"/CMP 0x%.8x,reg\n", data));
1967 /* the case of CMP reg32,m32 */
1971 "/abs const ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1972 p, d6, d5, d4, d3, d2, d1, data));
1973 FSHOW((stderr, "/CMP reg32,0x%.8x\n", data));
1975 /* the case of MOV m32,reg32 */
1979 "/abs const ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1980 p, d6, d5, d4, d3, d2, d1, data));
1981 FSHOW((stderr, "/MOV 0x%.8x,reg32\n", data));
1983 /* the case of MOV reg32,m32 */
1987 "/abs const ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1988 p, d6, d5, d4, d3, d2, d1, data));
1989 FSHOW((stderr, "/MOV reg32,0x%.8x\n", data));
1991 /* the case of LEA reg32,m32 */
1995 "abs const ref @%x: %.2x %.2x %.2x %.2x %.2x %.2x (%.8x)\n",
1996 p, d6, d5, d4, d3, d2, d1, data));
1997 FSHOW((stderr, "/LEA reg32,0x%.8x\n", data));
2003 /* If anything was found, print some information on the code
2007 "/compiled code object at %x: header words = %d, code words = %d\n",
2008 code, nheader_words, ncode_words));
2010 "/const start = %x, end = %x\n",
2011 constants_start_addr, constants_end_addr));
2013 "/code start = %x, end = %x\n",
2014 code_start_addr, code_end_addr));
2019 apply_code_fixups(struct code *old_code, struct code *new_code)
2021 int nheader_words, ncode_words, nwords;
2022 void *constants_start_addr, *constants_end_addr;
2023 void *code_start_addr, *code_end_addr;
2024 lispobj fixups = NIL;
2025 unsigned displacement = (unsigned)new_code - (unsigned)old_code;
2026 struct vector *fixups_vector;
2028 ncode_words = fixnum_value(new_code->code_size);
2029 nheader_words = HeaderValue(*(lispobj *)new_code);
2030 nwords = ncode_words + nheader_words;
2032 "/compiled code object at %x: header words = %d, code words = %d\n",
2033 new_code, nheader_words, ncode_words)); */
2034 constants_start_addr = (void *)new_code + 5*4;
2035 constants_end_addr = (void *)new_code + nheader_words*4;
2036 code_start_addr = (void *)new_code + nheader_words*4;
2037 code_end_addr = (void *)new_code + nwords*4;
2040 "/const start = %x, end = %x\n",
2041 constants_start_addr,constants_end_addr));
2043 "/code start = %x; end = %x\n",
2044 code_start_addr,code_end_addr));
2047 /* The first constant should be a pointer to the fixups for this
2048 code objects. Check. */
2049 fixups = new_code->constants[0];
2051 /* It will be 0 or the unbound-marker if there are no fixups, and
2052 * will be an other pointer if it is valid. */
2053 if ((fixups == 0) || (fixups == type_UnboundMarker) ||
2054 !is_lisp_pointer(fixups)) {
2055 /* Check for possible errors. */
2056 if (check_code_fixups)
2057 sniff_code_object(new_code, displacement);
2059 /*fprintf(stderr,"Fixups for code object not found!?\n");
2060 fprintf(stderr,"*** Compiled code object at %x: header_words=%d code_words=%d .\n",
2061 new_code, nheader_words, ncode_words);
2062 fprintf(stderr,"*** Const. start = %x; end= %x; Code start = %x; end = %x\n",
2063 constants_start_addr,constants_end_addr,
2064 code_start_addr,code_end_addr);*/
2068 fixups_vector = (struct vector *)native_pointer(fixups);
2070 /* Could be pointing to a forwarding pointer. */
2071 if (is_lisp_pointer(fixups) &&
2072 (find_page_index((void*)fixups_vector) != -1) &&
2073 (fixups_vector->header == 0x01)) {
2074 /* If so, then follow it. */
2075 /*SHOW("following pointer to a forwarding pointer");*/
2076 fixups_vector = (struct vector *)native_pointer((lispobj)fixups_vector->length);
2079 /*SHOW("got fixups");*/
2081 if (TypeOf(fixups_vector->header) == type_SimpleArrayUnsignedByte32) {
2082 /* Got the fixups for the code block. Now work through the vector,
2083 and apply a fixup at each address. */
2084 int length = fixnum_value(fixups_vector->length);
2086 for (i = 0; i < length; i++) {
2087 unsigned offset = fixups_vector->data[i];
2088 /* Now check the current value of offset. */
2089 unsigned old_value =
2090 *(unsigned *)((unsigned)code_start_addr + offset);
2092 /* If it's within the old_code object then it must be an
2093 * absolute fixup (relative ones are not saved) */
2094 if ((old_value >= (unsigned)old_code)
2095 && (old_value < ((unsigned)old_code + nwords*4)))
2096 /* So add the dispacement. */
2097 *(unsigned *)((unsigned)code_start_addr + offset) =
2098 old_value + displacement;
2100 /* It is outside the old code object so it must be a
2101 * relative fixup (absolute fixups are not saved). So
2102 * subtract the displacement. */
2103 *(unsigned *)((unsigned)code_start_addr + offset) =
2104 old_value - displacement;
2108 /* Check for possible errors. */
2109 if (check_code_fixups) {
2110 sniff_code_object(new_code,displacement);
2114 static struct code *
2115 trans_code(struct code *code)
2117 struct code *new_code;
2118 lispobj l_code, l_new_code;
2119 int nheader_words, ncode_words, nwords;
2120 unsigned long displacement;
2121 lispobj fheaderl, *prev_pointer;
2124 "\n/transporting code object located at 0x%08x\n",
2125 (unsigned long) code)); */
2127 /* If object has already been transported, just return pointer. */
2128 if (*((lispobj *)code) == 0x01)
2129 return (struct code*)(((lispobj *)code)[1]);
2131 gc_assert(TypeOf(code->header) == type_CodeHeader);
2133 /* Prepare to transport the code vector. */
2134 l_code = (lispobj) code | type_OtherPointer;
2136 ncode_words = fixnum_value(code->code_size);
2137 nheader_words = HeaderValue(code->header);
2138 nwords = ncode_words + nheader_words;
2139 nwords = CEILING(nwords, 2);
2141 l_new_code = copy_large_object(l_code, nwords);
2142 new_code = (struct code *) native_pointer(l_new_code);
2144 /* may not have been moved.. */
2145 if (new_code == code)
2148 displacement = l_new_code - l_code;
2152 "/old code object at 0x%08x, new code object at 0x%08x\n",
2153 (unsigned long) code,
2154 (unsigned long) new_code));
2155 FSHOW((stderr, "/Code object is %d words long.\n", nwords));
2158 /* Set forwarding pointer. */
2159 ((lispobj *)code)[0] = 0x01;
2160 ((lispobj *)code)[1] = l_new_code;
2162 /* Set forwarding pointers for all the function headers in the
2163 * code object. Also fix all self pointers. */
2165 fheaderl = code->entry_points;
2166 prev_pointer = &new_code->entry_points;
2168 while (fheaderl != NIL) {
2169 struct function *fheaderp, *nfheaderp;
2172 fheaderp = (struct function *) native_pointer(fheaderl);
2173 gc_assert(TypeOf(fheaderp->header) == type_FunctionHeader);
2175 /* Calculate the new function pointer and the new */
2176 /* function header. */
2177 nfheaderl = fheaderl + displacement;
2178 nfheaderp = (struct function *) native_pointer(nfheaderl);
2180 /* Set forwarding pointer. */
2181 ((lispobj *)fheaderp)[0] = 0x01;
2182 ((lispobj *)fheaderp)[1] = nfheaderl;
2184 /* Fix self pointer. */
2185 nfheaderp->self = nfheaderl + RAW_ADDR_OFFSET;
2187 *prev_pointer = nfheaderl;
2189 fheaderl = fheaderp->next;
2190 prev_pointer = &nfheaderp->next;
2193 /* sniff_code_object(new_code,displacement);*/
2194 apply_code_fixups(code,new_code);
2200 scav_code_header(lispobj *where, lispobj object)
2203 int n_header_words, n_code_words, n_words;
2204 lispobj entry_point; /* tagged pointer to entry point */
2205 struct function *function_ptr; /* untagged pointer to entry point */
2207 code = (struct code *) where;
2208 n_code_words = fixnum_value(code->code_size);
2209 n_header_words = HeaderValue(object);
2210 n_words = n_code_words + n_header_words;
2211 n_words = CEILING(n_words, 2);
2213 /* Scavenge the boxed section of the code data block. */
2214 scavenge(where + 1, n_header_words - 1);
2216 /* Scavenge the boxed section of each function object in the */
2217 /* code data block. */
2218 for (entry_point = code->entry_points;
2220 entry_point = function_ptr->next) {
2222 gc_assert(is_lisp_pointer(entry_point));
2224 function_ptr = (struct function *) native_pointer(entry_point);
2225 gc_assert(TypeOf(function_ptr->header) == type_FunctionHeader);
2227 scavenge(&function_ptr->name, 1);
2228 scavenge(&function_ptr->arglist, 1);
2229 scavenge(&function_ptr->type, 1);
2236 trans_code_header(lispobj object)
2240 ncode = trans_code((struct code *) native_pointer(object));
2241 return (lispobj) ncode | type_OtherPointer;
2245 size_code_header(lispobj *where)
2248 int nheader_words, ncode_words, nwords;
2250 code = (struct code *) where;
2252 ncode_words = fixnum_value(code->code_size);
2253 nheader_words = HeaderValue(code->header);
2254 nwords = ncode_words + nheader_words;
2255 nwords = CEILING(nwords, 2);
2261 scav_return_pc_header(lispobj *where, lispobj object)
2263 lose("attempted to scavenge a return PC header where=0x%08x object=0x%08x",
2264 (unsigned long) where,
2265 (unsigned long) object);
2266 return 0; /* bogus return value to satisfy static type checking */
2270 trans_return_pc_header(lispobj object)
2272 struct function *return_pc;
2273 unsigned long offset;
2274 struct code *code, *ncode;
2276 SHOW("/trans_return_pc_header: Will this work?");
2278 return_pc = (struct function *) native_pointer(object);
2279 offset = HeaderValue(return_pc->header) * 4;
2281 /* Transport the whole code object. */
2282 code = (struct code *) ((unsigned long) return_pc - offset);
2283 ncode = trans_code(code);
2285 return ((lispobj) ncode + offset) | type_OtherPointer;
2288 /* On the 386, closures hold a pointer to the raw address instead of the
2289 * function object. */
2292 scav_closure_header(lispobj *where, lispobj object)
2294 struct closure *closure;
2297 closure = (struct closure *)where;
2298 fun = closure->function - RAW_ADDR_OFFSET;
2300 /* The function may have moved so update the raw address. But
2301 * don't write unnecessarily. */
2302 if (closure->function != fun + RAW_ADDR_OFFSET)
2303 closure->function = fun + RAW_ADDR_OFFSET;
2310 scav_function_header(lispobj *where, lispobj object)
2312 lose("attempted to scavenge a function header where=0x%08x object=0x%08x",
2313 (unsigned long) where,
2314 (unsigned long) object);
2315 return 0; /* bogus return value to satisfy static type checking */
2319 trans_function_header(lispobj object)
2321 struct function *fheader;
2322 unsigned long offset;
2323 struct code *code, *ncode;
2325 fheader = (struct function *) native_pointer(object);
2326 offset = HeaderValue(fheader->header) * 4;
2328 /* Transport the whole code object. */
2329 code = (struct code *) ((unsigned long) fheader - offset);
2330 ncode = trans_code(code);
2332 return ((lispobj) ncode + offset) | type_FunctionPointer;
2340 scav_instance_pointer(lispobj *where, lispobj object)
2342 lispobj copy, *first_pointer;
2344 /* Object is a pointer into from space - not a FP. */
2345 copy = trans_boxed(object);
2347 gc_assert(copy != object);
2349 first_pointer = (lispobj *) native_pointer(object);
2351 /* Set forwarding pointer. */
2352 first_pointer[0] = 0x01;
2353 first_pointer[1] = copy;
2363 static lispobj trans_list(lispobj object);
2366 scav_list_pointer(lispobj *where, lispobj object)
2368 lispobj first, *first_pointer;
2370 gc_assert(is_lisp_pointer(object));
2372 /* Object is a pointer into from space - not FP. */
2374 first = trans_list(object);
2375 gc_assert(first != object);
2377 first_pointer = (lispobj *) native_pointer(object);
2379 /* Set forwarding pointer */
2380 first_pointer[0] = 0x01;
2381 first_pointer[1] = first;
2383 gc_assert(is_lisp_pointer(first));
2384 gc_assert(!from_space_p(first));
2390 trans_list(lispobj object)
2392 lispobj new_list_pointer;
2393 struct cons *cons, *new_cons;
2396 gc_assert(from_space_p(object));
2398 cons = (struct cons *) native_pointer(object);
2400 /* Copy 'object'. */
2401 new_cons = (struct cons *) gc_quick_alloc(sizeof(struct cons));
2402 new_cons->car = cons->car;
2403 new_cons->cdr = cons->cdr; /* updated later */
2404 new_list_pointer = (lispobj)new_cons | LowtagOf(object);
2406 /* Grab the cdr before it is clobbered. */
2409 /* Set forwarding pointer (clobbers start of list). */
2411 cons->cdr = new_list_pointer;
2413 /* Try to linearize the list in the cdr direction to help reduce
2417 struct cons *cdr_cons, *new_cdr_cons;
2419 if (LowtagOf(cdr) != type_ListPointer || !from_space_p(cdr)
2420 || (*((lispobj *)native_pointer(cdr)) == 0x01))
2423 cdr_cons = (struct cons *) native_pointer(cdr);
2426 new_cdr_cons = (struct cons*) gc_quick_alloc(sizeof(struct cons));
2427 new_cdr_cons->car = cdr_cons->car;
2428 new_cdr_cons->cdr = cdr_cons->cdr;
2429 new_cdr = (lispobj)new_cdr_cons | LowtagOf(cdr);
2431 /* Grab the cdr before it is clobbered. */
2432 cdr = cdr_cons->cdr;
2434 /* Set forwarding pointer. */
2435 cdr_cons->car = 0x01;
2436 cdr_cons->cdr = new_cdr;
2438 /* Update the cdr of the last cons copied into new space to
2439 * keep the newspace scavenge from having to do it. */
2440 new_cons->cdr = new_cdr;
2442 new_cons = new_cdr_cons;
2445 return new_list_pointer;
2450 * scavenging and transporting other pointers
2454 scav_other_pointer(lispobj *where, lispobj object)
2456 lispobj first, *first_pointer;
2458 gc_assert(is_lisp_pointer(object));
2460 /* Object is a pointer into from space - not FP. */
2461 first_pointer = (lispobj *) native_pointer(object);
2463 first = (transother[TypeOf(*first_pointer)])(object);
2465 if (first != object) {
2466 /* Set forwarding pointer. */
2467 first_pointer[0] = 0x01;
2468 first_pointer[1] = first;
2472 gc_assert(is_lisp_pointer(first));
2473 gc_assert(!from_space_p(first));
2479 * immediate, boxed, and unboxed objects
2483 size_pointer(lispobj *where)
2489 scav_immediate(lispobj *where, lispobj object)
2495 trans_immediate(lispobj object)
2497 lose("trying to transport an immediate");
2498 return NIL; /* bogus return value to satisfy static type checking */
2502 size_immediate(lispobj *where)
2509 scav_boxed(lispobj *where, lispobj object)
2515 trans_boxed(lispobj object)
2518 unsigned long length;
2520 gc_assert(is_lisp_pointer(object));
2522 header = *((lispobj *) native_pointer(object));
2523 length = HeaderValue(header) + 1;
2524 length = CEILING(length, 2);
2526 return copy_object(object, length);
2530 trans_boxed_large(lispobj object)
2533 unsigned long length;
2535 gc_assert(is_lisp_pointer(object));
2537 header = *((lispobj *) native_pointer(object));
2538 length = HeaderValue(header) + 1;
2539 length = CEILING(length, 2);
2541 return copy_large_object(object, length);
2545 size_boxed(lispobj *where)
2548 unsigned long length;
2551 length = HeaderValue(header) + 1;
2552 length = CEILING(length, 2);
2558 scav_fdefn(lispobj *where, lispobj object)
2560 struct fdefn *fdefn;
2562 fdefn = (struct fdefn *)where;
2564 /* FSHOW((stderr, "scav_fdefn, function = %p, raw_addr = %p\n",
2565 fdefn->function, fdefn->raw_addr)); */
2567 if ((char *)(fdefn->function + RAW_ADDR_OFFSET) == fdefn->raw_addr) {
2568 scavenge(where + 1, sizeof(struct fdefn)/sizeof(lispobj) - 1);
2570 /* Don't write unnecessarily. */
2571 if (fdefn->raw_addr != (char *)(fdefn->function + RAW_ADDR_OFFSET))
2572 fdefn->raw_addr = (char *)(fdefn->function + RAW_ADDR_OFFSET);
2574 return sizeof(struct fdefn) / sizeof(lispobj);
2581 scav_unboxed(lispobj *where, lispobj object)
2583 unsigned long length;
2585 length = HeaderValue(object) + 1;
2586 length = CEILING(length, 2);
2592 trans_unboxed(lispobj object)
2595 unsigned long length;
2598 gc_assert(is_lisp_pointer(object));
2600 header = *((lispobj *) native_pointer(object));
2601 length = HeaderValue(header) + 1;
2602 length = CEILING(length, 2);
2604 return copy_unboxed_object(object, length);
2608 trans_unboxed_large(lispobj object)
2611 unsigned long length;
2614 gc_assert(is_lisp_pointer(object));
2616 header = *((lispobj *) native_pointer(object));
2617 length = HeaderValue(header) + 1;
2618 length = CEILING(length, 2);
2620 return copy_large_unboxed_object(object, length);
2624 size_unboxed(lispobj *where)
2627 unsigned long length;
2630 length = HeaderValue(header) + 1;
2631 length = CEILING(length, 2);
2637 * vector-like objects
2640 #define NWORDS(x,y) (CEILING((x),(y)) / (y))
2643 scav_string(lispobj *where, lispobj object)
2645 struct vector *vector;
2648 /* NOTE: Strings contain one more byte of data than the length */
2649 /* slot indicates. */
2651 vector = (struct vector *) where;
2652 length = fixnum_value(vector->length) + 1;
2653 nwords = CEILING(NWORDS(length, 4) + 2, 2);
2659 trans_string(lispobj object)
2661 struct vector *vector;
2664 gc_assert(is_lisp_pointer(object));
2666 /* NOTE: A string contains one more byte of data (a terminating
2667 * '\0' to help when interfacing with C functions) than indicated
2668 * by the length slot. */
2670 vector = (struct vector *) native_pointer(object);
2671 length = fixnum_value(vector->length) + 1;
2672 nwords = CEILING(NWORDS(length, 4) + 2, 2);
2674 return copy_large_unboxed_object(object, nwords);
2678 size_string(lispobj *where)
2680 struct vector *vector;
2683 /* NOTE: A string contains one more byte of data (a terminating
2684 * '\0' to help when interfacing with C functions) than indicated
2685 * by the length slot. */
2687 vector = (struct vector *) where;
2688 length = fixnum_value(vector->length) + 1;
2689 nwords = CEILING(NWORDS(length, 4) + 2, 2);
2694 /* FIXME: What does this mean? */
2695 int gencgc_hash = 1;
2698 scav_vector(lispobj *where, lispobj object)
2700 unsigned int kv_length;
2702 unsigned int length = 0; /* (0 = dummy to stop GCC warning) */
2703 lispobj *hash_table;
2704 lispobj empty_symbol;
2705 unsigned int *index_vector = NULL; /* (NULL = dummy to stop GCC warning) */
2706 unsigned int *next_vector = NULL; /* (NULL = dummy to stop GCC warning) */
2707 unsigned int *hash_vector = NULL; /* (NULL = dummy to stop GCC warning) */
2709 unsigned next_vector_length = 0;
2711 /* FIXME: A comment explaining this would be nice. It looks as
2712 * though SB-VM:VECTOR-VALID-HASHING-SUBTYPE is set for EQ-based
2713 * hash tables in the Lisp HASH-TABLE code, and nowhere else. */
2714 if (HeaderValue(object) != subtype_VectorValidHashing)
2718 /* This is set for backward compatibility. FIXME: Do we need
2720 *where = (subtype_VectorMustRehash << type_Bits) | type_SimpleVector;
2724 kv_length = fixnum_value(where[1]);
2725 kv_vector = where + 2; /* Skip the header and length. */
2726 /*FSHOW((stderr,"/kv_length = %d\n", kv_length));*/
2728 /* Scavenge element 0, which may be a hash-table structure. */
2729 scavenge(where+2, 1);
2730 if (!is_lisp_pointer(where[2])) {
2731 lose("no pointer at %x in hash table", where[2]);
2733 hash_table = (lispobj *)native_pointer(where[2]);
2734 /*FSHOW((stderr,"/hash_table = %x\n", hash_table));*/
2735 if (TypeOf(hash_table[0]) != type_InstanceHeader) {
2736 lose("hash table not instance (%x at %x)", hash_table[0], hash_table);
2739 /* Scavenge element 1, which should be some internal symbol that
2740 * the hash table code reserves for marking empty slots. */
2741 scavenge(where+3, 1);
2742 if (!is_lisp_pointer(where[3])) {
2743 lose("not empty-hash-table-slot symbol pointer: %x", where[3]);
2745 empty_symbol = where[3];
2746 /* fprintf(stderr,"* empty_symbol = %x\n", empty_symbol);*/
2747 if (TypeOf(*(lispobj *)native_pointer(empty_symbol)) != type_SymbolHeader) {
2748 lose("not a symbol where empty-hash-table-slot symbol expected: %x",
2749 *(lispobj *)native_pointer(empty_symbol));
2752 /* Scavenge hash table, which will fix the positions of the other
2753 * needed objects. */
2754 scavenge(hash_table, 16);
2756 /* Cross-check the kv_vector. */
2757 if (where != (lispobj *)native_pointer(hash_table[9])) {
2758 lose("hash_table table!=this table %x", hash_table[9]);
2762 weak_p_obj = hash_table[10];
2766 lispobj index_vector_obj = hash_table[13];
2768 if (is_lisp_pointer(index_vector_obj) &&
2769 (TypeOf(*(lispobj *)native_pointer(index_vector_obj)) == type_SimpleArrayUnsignedByte32)) {
2770 index_vector = ((unsigned int *)native_pointer(index_vector_obj)) + 2;
2771 /*FSHOW((stderr, "/index_vector = %x\n",index_vector));*/
2772 length = fixnum_value(((unsigned int *)native_pointer(index_vector_obj))[1]);
2773 /*FSHOW((stderr, "/length = %d\n", length));*/
2775 lose("invalid index_vector %x", index_vector_obj);
2781 lispobj next_vector_obj = hash_table[14];
2783 if (is_lisp_pointer(next_vector_obj) &&
2784 (TypeOf(*(lispobj *)native_pointer(next_vector_obj)) == type_SimpleArrayUnsignedByte32)) {
2785 next_vector = ((unsigned int *)native_pointer(next_vector_obj)) + 2;
2786 /*FSHOW((stderr, "/next_vector = %x\n", next_vector));*/
2787 next_vector_length = fixnum_value(((unsigned int *)native_pointer(next_vector_obj))[1]);
2788 /*FSHOW((stderr, "/next_vector_length = %d\n", next_vector_length));*/
2790 lose("invalid next_vector %x", next_vector_obj);
2794 /* maybe hash vector */
2796 /* FIXME: This bare "15" offset should become a symbolic
2797 * expression of some sort. And all the other bare offsets
2798 * too. And the bare "16" in scavenge(hash_table, 16). And
2799 * probably other stuff too. Ugh.. */
2800 lispobj hash_vector_obj = hash_table[15];
2802 if (is_lisp_pointer(hash_vector_obj) &&
2803 (TypeOf(*(lispobj *)native_pointer(hash_vector_obj))
2804 == type_SimpleArrayUnsignedByte32)) {
2805 hash_vector = ((unsigned int *)native_pointer(hash_vector_obj)) + 2;
2806 /*FSHOW((stderr, "/hash_vector = %x\n", hash_vector));*/
2807 gc_assert(fixnum_value(((unsigned int *)native_pointer(hash_vector_obj))[1])
2808 == next_vector_length);
2811 /*FSHOW((stderr, "/no hash_vector: %x\n", hash_vector_obj));*/
2815 /* These lengths could be different as the index_vector can be a
2816 * different length from the others, a larger index_vector could help
2817 * reduce collisions. */
2818 gc_assert(next_vector_length*2 == kv_length);
2820 /* now all set up.. */
2822 /* Work through the KV vector. */
2825 for (i = 1; i < next_vector_length; i++) {
2826 lispobj old_key = kv_vector[2*i];
2827 unsigned int old_index = (old_key & 0x1fffffff)%length;
2829 /* Scavenge the key and value. */
2830 scavenge(&kv_vector[2*i],2);
2832 /* Check whether the key has moved and is EQ based. */
2834 lispobj new_key = kv_vector[2*i];
2835 unsigned int new_index = (new_key & 0x1fffffff)%length;
2837 if ((old_index != new_index) &&
2838 ((!hash_vector) || (hash_vector[i] == 0x80000000)) &&
2839 ((new_key != empty_symbol) ||
2840 (kv_vector[2*i] != empty_symbol))) {
2843 "* EQ key %d moved from %x to %x; index %d to %d\n",
2844 i, old_key, new_key, old_index, new_index));*/
2846 if (index_vector[old_index] != 0) {
2847 /*FSHOW((stderr, "/P1 %d\n", index_vector[old_index]));*/
2849 /* Unlink the key from the old_index chain. */
2850 if (index_vector[old_index] == i) {
2851 /*FSHOW((stderr, "/P2a %d\n", next_vector[i]));*/
2852 index_vector[old_index] = next_vector[i];
2853 /* Link it into the needing rehash chain. */
2854 next_vector[i] = fixnum_value(hash_table[11]);
2855 hash_table[11] = make_fixnum(i);
2858 unsigned prior = index_vector[old_index];
2859 unsigned next = next_vector[prior];
2861 /*FSHOW((stderr, "/P3a %d %d\n", prior, next));*/
2864 /*FSHOW((stderr, "/P3b %d %d\n", prior, next));*/
2867 next_vector[prior] = next_vector[next];
2868 /* Link it into the needing rehash
2871 fixnum_value(hash_table[11]);
2872 hash_table[11] = make_fixnum(next);
2877 next = next_vector[next];
2885 return (CEILING(kv_length + 2, 2));
2889 trans_vector(lispobj object)
2891 struct vector *vector;
2894 gc_assert(is_lisp_pointer(object));
2896 vector = (struct vector *) native_pointer(object);
2898 length = fixnum_value(vector->length);
2899 nwords = CEILING(length + 2, 2);
2901 return copy_large_object(object, nwords);
2905 size_vector(lispobj *where)
2907 struct vector *vector;
2910 vector = (struct vector *) where;
2911 length = fixnum_value(vector->length);
2912 nwords = CEILING(length + 2, 2);
2919 scav_vector_bit(lispobj *where, lispobj object)
2921 struct vector *vector;
2924 vector = (struct vector *) where;
2925 length = fixnum_value(vector->length);
2926 nwords = CEILING(NWORDS(length, 32) + 2, 2);
2932 trans_vector_bit(lispobj object)
2934 struct vector *vector;
2937 gc_assert(is_lisp_pointer(object));
2939 vector = (struct vector *) native_pointer(object);
2940 length = fixnum_value(vector->length);
2941 nwords = CEILING(NWORDS(length, 32) + 2, 2);
2943 return copy_large_unboxed_object(object, nwords);
2947 size_vector_bit(lispobj *where)
2949 struct vector *vector;
2952 vector = (struct vector *) where;
2953 length = fixnum_value(vector->length);
2954 nwords = CEILING(NWORDS(length, 32) + 2, 2);
2961 scav_vector_unsigned_byte_2(lispobj *where, lispobj object)
2963 struct vector *vector;
2966 vector = (struct vector *) where;
2967 length = fixnum_value(vector->length);
2968 nwords = CEILING(NWORDS(length, 16) + 2, 2);
2974 trans_vector_unsigned_byte_2(lispobj object)
2976 struct vector *vector;
2979 gc_assert(is_lisp_pointer(object));
2981 vector = (struct vector *) native_pointer(object);
2982 length = fixnum_value(vector->length);
2983 nwords = CEILING(NWORDS(length, 16) + 2, 2);
2985 return copy_large_unboxed_object(object, nwords);
2989 size_vector_unsigned_byte_2(lispobj *where)
2991 struct vector *vector;
2994 vector = (struct vector *) where;
2995 length = fixnum_value(vector->length);
2996 nwords = CEILING(NWORDS(length, 16) + 2, 2);
3003 scav_vector_unsigned_byte_4(lispobj *where, lispobj object)
3005 struct vector *vector;
3008 vector = (struct vector *) where;
3009 length = fixnum_value(vector->length);
3010 nwords = CEILING(NWORDS(length, 8) + 2, 2);
3016 trans_vector_unsigned_byte_4(lispobj object)
3018 struct vector *vector;
3021 gc_assert(is_lisp_pointer(object));
3023 vector = (struct vector *) native_pointer(object);
3024 length = fixnum_value(vector->length);
3025 nwords = CEILING(NWORDS(length, 8) + 2, 2);
3027 return copy_large_unboxed_object(object, nwords);
3031 size_vector_unsigned_byte_4(lispobj *where)
3033 struct vector *vector;
3036 vector = (struct vector *) where;
3037 length = fixnum_value(vector->length);
3038 nwords = CEILING(NWORDS(length, 8) + 2, 2);
3044 scav_vector_unsigned_byte_8(lispobj *where, lispobj object)
3046 struct vector *vector;
3049 vector = (struct vector *) where;
3050 length = fixnum_value(vector->length);
3051 nwords = CEILING(NWORDS(length, 4) + 2, 2);
3057 trans_vector_unsigned_byte_8(lispobj object)
3059 struct vector *vector;
3062 gc_assert(is_lisp_pointer(object));
3064 vector = (struct vector *) native_pointer(object);
3065 length = fixnum_value(vector->length);
3066 nwords = CEILING(NWORDS(length, 4) + 2, 2);
3068 return copy_large_unboxed_object(object, nwords);
3072 size_vector_unsigned_byte_8(lispobj *where)
3074 struct vector *vector;
3077 vector = (struct vector *) where;
3078 length = fixnum_value(vector->length);
3079 nwords = CEILING(NWORDS(length, 4) + 2, 2);
3086 scav_vector_unsigned_byte_16(lispobj *where, lispobj object)
3088 struct vector *vector;
3091 vector = (struct vector *) where;
3092 length = fixnum_value(vector->length);
3093 nwords = CEILING(NWORDS(length, 2) + 2, 2);
3099 trans_vector_unsigned_byte_16(lispobj object)
3101 struct vector *vector;
3104 gc_assert(is_lisp_pointer(object));
3106 vector = (struct vector *) native_pointer(object);
3107 length = fixnum_value(vector->length);
3108 nwords = CEILING(NWORDS(length, 2) + 2, 2);
3110 return copy_large_unboxed_object(object, nwords);
3114 size_vector_unsigned_byte_16(lispobj *where)
3116 struct vector *vector;
3119 vector = (struct vector *) where;
3120 length = fixnum_value(vector->length);
3121 nwords = CEILING(NWORDS(length, 2) + 2, 2);
3127 scav_vector_unsigned_byte_32(lispobj *where, lispobj object)
3129 struct vector *vector;
3132 vector = (struct vector *) where;
3133 length = fixnum_value(vector->length);
3134 nwords = CEILING(length + 2, 2);
3140 trans_vector_unsigned_byte_32(lispobj object)
3142 struct vector *vector;
3145 gc_assert(is_lisp_pointer(object));
3147 vector = (struct vector *) native_pointer(object);
3148 length = fixnum_value(vector->length);
3149 nwords = CEILING(length + 2, 2);
3151 return copy_large_unboxed_object(object, nwords);
3155 size_vector_unsigned_byte_32(lispobj *where)
3157 struct vector *vector;
3160 vector = (struct vector *) where;
3161 length = fixnum_value(vector->length);
3162 nwords = CEILING(length + 2, 2);
3168 scav_vector_single_float(lispobj *where, lispobj object)
3170 struct vector *vector;
3173 vector = (struct vector *) where;
3174 length = fixnum_value(vector->length);
3175 nwords = CEILING(length + 2, 2);
3181 trans_vector_single_float(lispobj object)
3183 struct vector *vector;
3186 gc_assert(is_lisp_pointer(object));
3188 vector = (struct vector *) native_pointer(object);
3189 length = fixnum_value(vector->length);
3190 nwords = CEILING(length + 2, 2);
3192 return copy_large_unboxed_object(object, nwords);
3196 size_vector_single_float(lispobj *where)
3198 struct vector *vector;
3201 vector = (struct vector *) where;
3202 length = fixnum_value(vector->length);
3203 nwords = CEILING(length + 2, 2);
3209 scav_vector_double_float(lispobj *where, lispobj object)
3211 struct vector *vector;
3214 vector = (struct vector *) where;
3215 length = fixnum_value(vector->length);
3216 nwords = CEILING(length * 2 + 2, 2);
3222 trans_vector_double_float(lispobj object)
3224 struct vector *vector;
3227 gc_assert(is_lisp_pointer(object));
3229 vector = (struct vector *) native_pointer(object);
3230 length = fixnum_value(vector->length);
3231 nwords = CEILING(length * 2 + 2, 2);
3233 return copy_large_unboxed_object(object, nwords);
3237 size_vector_double_float(lispobj *where)
3239 struct vector *vector;
3242 vector = (struct vector *) where;
3243 length = fixnum_value(vector->length);
3244 nwords = CEILING(length * 2 + 2, 2);
3249 #ifdef type_SimpleArrayLongFloat
3251 scav_vector_long_float(lispobj *where, lispobj object)
3253 struct vector *vector;
3256 vector = (struct vector *) where;
3257 length = fixnum_value(vector->length);
3258 nwords = CEILING(length * 3 + 2, 2);
3264 trans_vector_long_float(lispobj object)
3266 struct vector *vector;
3269 gc_assert(is_lisp_pointer(object));
3271 vector = (struct vector *) native_pointer(object);
3272 length = fixnum_value(vector->length);
3273 nwords = CEILING(length * 3 + 2, 2);
3275 return copy_large_unboxed_object(object, nwords);
3279 size_vector_long_float(lispobj *where)
3281 struct vector *vector;
3284 vector = (struct vector *) where;
3285 length = fixnum_value(vector->length);
3286 nwords = CEILING(length * 3 + 2, 2);
3293 #ifdef type_SimpleArrayComplexSingleFloat
3295 scav_vector_complex_single_float(lispobj *where, lispobj object)
3297 struct vector *vector;
3300 vector = (struct vector *) where;
3301 length = fixnum_value(vector->length);
3302 nwords = CEILING(length * 2 + 2, 2);
3308 trans_vector_complex_single_float(lispobj object)
3310 struct vector *vector;
3313 gc_assert(is_lisp_pointer(object));
3315 vector = (struct vector *) native_pointer(object);
3316 length = fixnum_value(vector->length);
3317 nwords = CEILING(length * 2 + 2, 2);
3319 return copy_large_unboxed_object(object, nwords);
3323 size_vector_complex_single_float(lispobj *where)
3325 struct vector *vector;
3328 vector = (struct vector *) where;
3329 length = fixnum_value(vector->length);
3330 nwords = CEILING(length * 2 + 2, 2);
3336 #ifdef type_SimpleArrayComplexDoubleFloat
3338 scav_vector_complex_double_float(lispobj *where, lispobj object)
3340 struct vector *vector;
3343 vector = (struct vector *) where;
3344 length = fixnum_value(vector->length);
3345 nwords = CEILING(length * 4 + 2, 2);
3351 trans_vector_complex_double_float(lispobj object)
3353 struct vector *vector;
3356 gc_assert(is_lisp_pointer(object));
3358 vector = (struct vector *) native_pointer(object);
3359 length = fixnum_value(vector->length);
3360 nwords = CEILING(length * 4 + 2, 2);
3362 return copy_large_unboxed_object(object, nwords);
3366 size_vector_complex_double_float(lispobj *where)
3368 struct vector *vector;
3371 vector = (struct vector *) where;
3372 length = fixnum_value(vector->length);
3373 nwords = CEILING(length * 4 + 2, 2);
3380 #ifdef type_SimpleArrayComplexLongFloat
3382 scav_vector_complex_long_float(lispobj *where, lispobj object)
3384 struct vector *vector;
3387 vector = (struct vector *) where;
3388 length = fixnum_value(vector->length);
3389 nwords = CEILING(length * 6 + 2, 2);
3395 trans_vector_complex_long_float(lispobj object)
3397 struct vector *vector;
3400 gc_assert(is_lisp_pointer(object));
3402 vector = (struct vector *) native_pointer(object);
3403 length = fixnum_value(vector->length);
3404 nwords = CEILING(length * 6 + 2, 2);
3406 return copy_large_unboxed_object(object, nwords);
3410 size_vector_complex_long_float(lispobj *where)
3412 struct vector *vector;
3415 vector = (struct vector *) where;
3416 length = fixnum_value(vector->length);
3417 nwords = CEILING(length * 6 + 2, 2);
3428 /* XX This is a hack adapted from cgc.c. These don't work too well with the
3429 * gencgc as a list of the weak pointers is maintained within the
3430 * objects which causes writes to the pages. A limited attempt is made
3431 * to avoid unnecessary writes, but this needs a re-think. */
3433 #define WEAK_POINTER_NWORDS \
3434 CEILING((sizeof(struct weak_pointer) / sizeof(lispobj)), 2)
3437 scav_weak_pointer(lispobj *where, lispobj object)
3439 struct weak_pointer *wp = weak_pointers;
3440 /* Push the weak pointer onto the list of weak pointers.
3441 * Do I have to watch for duplicates? Originally this was
3442 * part of trans_weak_pointer but that didn't work in the
3443 * case where the WP was in a promoted region.
3446 /* Check whether it's already in the list. */
3447 while (wp != NULL) {
3448 if (wp == (struct weak_pointer*)where) {
3454 /* Add it to the start of the list. */
3455 wp = (struct weak_pointer*)where;
3456 if (wp->next != weak_pointers) {
3457 wp->next = weak_pointers;
3459 /*SHOW("avoided write to weak pointer");*/
3464 /* Do not let GC scavenge the value slot of the weak pointer.
3465 * (That is why it is a weak pointer.) */
3467 return WEAK_POINTER_NWORDS;
3471 trans_weak_pointer(lispobj object)
3474 /* struct weak_pointer *wp; */
3476 gc_assert(is_lisp_pointer(object));
3478 #if defined(DEBUG_WEAK)
3479 FSHOW((stderr, "Transporting weak pointer from 0x%08x\n", object));
3482 /* Need to remember where all the weak pointers are that have */
3483 /* been transported so they can be fixed up in a post-GC pass. */
3485 copy = copy_object(object, WEAK_POINTER_NWORDS);
3486 /* wp = (struct weak_pointer *) native_pointer(copy);*/
3489 /* Push the weak pointer onto the list of weak pointers. */
3490 /* wp->next = weak_pointers;
3491 * weak_pointers = wp;*/
3497 size_weak_pointer(lispobj *where)
3499 return WEAK_POINTER_NWORDS;
3502 void scan_weak_pointers(void)
3504 struct weak_pointer *wp;
3505 for (wp = weak_pointers; wp != NULL; wp = wp->next) {
3506 lispobj value = wp->value;
3507 lispobj *first_pointer;
3509 first_pointer = (lispobj *)native_pointer(value);
3512 FSHOW((stderr, "/weak pointer at 0x%08x\n", (unsigned long) wp));
3513 FSHOW((stderr, "/value: 0x%08x\n", (unsigned long) value));
3516 if (is_lisp_pointer(value) && from_space_p(value)) {
3517 /* Now, we need to check whether the object has been forwarded. If
3518 * it has been, the weak pointer is still good and needs to be
3519 * updated. Otherwise, the weak pointer needs to be nil'ed
3521 if (first_pointer[0] == 0x01) {
3522 wp->value = first_pointer[1];
3538 scav_lose(lispobj *where, lispobj object)
3540 lose("no scavenge function for object 0x%08x", (unsigned long) object);
3541 return 0; /* bogus return value to satisfy static type checking */
3545 trans_lose(lispobj object)
3547 lose("no transport function for object 0x%08x", (unsigned long) object);
3548 return NIL; /* bogus return value to satisfy static type checking */
3552 size_lose(lispobj *where)
3554 lose("no size function for object at 0x%08x", (unsigned long) where);
3555 return 1; /* bogus return value to satisfy static type checking */
3559 gc_init_tables(void)
3563 /* Set default value in all slots of scavenge table. */
3564 for (i = 0; i < 256; i++) { /* FIXME: bare constant length, ick! */
3565 scavtab[i] = scav_lose;
3568 /* For each type which can be selected by the low 3 bits of the tag
3569 * alone, set multiple entries in our 8-bit scavenge table (one for each
3570 * possible value of the high 5 bits). */
3571 for (i = 0; i < 32; i++) { /* FIXME: bare constant length, ick! */
3572 scavtab[type_EvenFixnum|(i<<3)] = scav_immediate;
3573 scavtab[type_FunctionPointer|(i<<3)] = scav_function_pointer;
3574 /* OtherImmediate0 */
3575 scavtab[type_ListPointer|(i<<3)] = scav_list_pointer;
3576 scavtab[type_OddFixnum|(i<<3)] = scav_immediate;
3577 scavtab[type_InstancePointer|(i<<3)] = scav_instance_pointer;
3578 /* OtherImmediate1 */
3579 scavtab[type_OtherPointer|(i<<3)] = scav_other_pointer;
3582 /* Other-pointer types (those selected by all eight bits of the tag) get
3583 * one entry each in the scavenge table. */
3584 scavtab[type_Bignum] = scav_unboxed;
3585 scavtab[type_Ratio] = scav_boxed;
3586 scavtab[type_SingleFloat] = scav_unboxed;
3587 scavtab[type_DoubleFloat] = scav_unboxed;
3588 #ifdef type_LongFloat
3589 scavtab[type_LongFloat] = scav_unboxed;
3591 scavtab[type_Complex] = scav_boxed;
3592 #ifdef type_ComplexSingleFloat
3593 scavtab[type_ComplexSingleFloat] = scav_unboxed;
3595 #ifdef type_ComplexDoubleFloat
3596 scavtab[type_ComplexDoubleFloat] = scav_unboxed;
3598 #ifdef type_ComplexLongFloat
3599 scavtab[type_ComplexLongFloat] = scav_unboxed;
3601 scavtab[type_SimpleArray] = scav_boxed;
3602 scavtab[type_SimpleString] = scav_string;
3603 scavtab[type_SimpleBitVector] = scav_vector_bit;
3604 scavtab[type_SimpleVector] = scav_vector;
3605 scavtab[type_SimpleArrayUnsignedByte2] = scav_vector_unsigned_byte_2;
3606 scavtab[type_SimpleArrayUnsignedByte4] = scav_vector_unsigned_byte_4;
3607 scavtab[type_SimpleArrayUnsignedByte8] = scav_vector_unsigned_byte_8;
3608 scavtab[type_SimpleArrayUnsignedByte16] = scav_vector_unsigned_byte_16;
3609 scavtab[type_SimpleArrayUnsignedByte32] = scav_vector_unsigned_byte_32;
3610 #ifdef type_SimpleArraySignedByte8
3611 scavtab[type_SimpleArraySignedByte8] = scav_vector_unsigned_byte_8;
3613 #ifdef type_SimpleArraySignedByte16
3614 scavtab[type_SimpleArraySignedByte16] = scav_vector_unsigned_byte_16;
3616 #ifdef type_SimpleArraySignedByte30
3617 scavtab[type_SimpleArraySignedByte30] = scav_vector_unsigned_byte_32;
3619 #ifdef type_SimpleArraySignedByte32
3620 scavtab[type_SimpleArraySignedByte32] = scav_vector_unsigned_byte_32;
3622 scavtab[type_SimpleArraySingleFloat] = scav_vector_single_float;
3623 scavtab[type_SimpleArrayDoubleFloat] = scav_vector_double_float;
3624 #ifdef type_SimpleArrayLongFloat
3625 scavtab[type_SimpleArrayLongFloat] = scav_vector_long_float;
3627 #ifdef type_SimpleArrayComplexSingleFloat
3628 scavtab[type_SimpleArrayComplexSingleFloat] = scav_vector_complex_single_float;
3630 #ifdef type_SimpleArrayComplexDoubleFloat
3631 scavtab[type_SimpleArrayComplexDoubleFloat] = scav_vector_complex_double_float;
3633 #ifdef type_SimpleArrayComplexLongFloat
3634 scavtab[type_SimpleArrayComplexLongFloat] = scav_vector_complex_long_float;
3636 scavtab[type_ComplexString] = scav_boxed;
3637 scavtab[type_ComplexBitVector] = scav_boxed;
3638 scavtab[type_ComplexVector] = scav_boxed;
3639 scavtab[type_ComplexArray] = scav_boxed;
3640 scavtab[type_CodeHeader] = scav_code_header;
3641 /*scavtab[type_FunctionHeader] = scav_function_header;*/
3642 /*scavtab[type_ClosureFunctionHeader] = scav_function_header;*/
3643 /*scavtab[type_ReturnPcHeader] = scav_return_pc_header;*/
3645 scavtab[type_ClosureHeader] = scav_closure_header;
3646 scavtab[type_FuncallableInstanceHeader] = scav_closure_header;
3647 scavtab[type_ByteCodeFunction] = scav_closure_header;
3648 scavtab[type_ByteCodeClosure] = scav_closure_header;
3650 scavtab[type_ClosureHeader] = scav_boxed;
3651 scavtab[type_FuncallableInstanceHeader] = scav_boxed;
3652 scavtab[type_ByteCodeFunction] = scav_boxed;
3653 scavtab[type_ByteCodeClosure] = scav_boxed;
3655 scavtab[type_ValueCellHeader] = scav_boxed;
3656 scavtab[type_SymbolHeader] = scav_boxed;
3657 scavtab[type_BaseChar] = scav_immediate;
3658 scavtab[type_Sap] = scav_unboxed;
3659 scavtab[type_UnboundMarker] = scav_immediate;
3660 scavtab[type_WeakPointer] = scav_weak_pointer;
3661 scavtab[type_InstanceHeader] = scav_boxed;
3662 scavtab[type_Fdefn] = scav_fdefn;
3664 /* transport other table, initialized same way as scavtab */
3665 for (i = 0; i < 256; i++)
3666 transother[i] = trans_lose;
3667 transother[type_Bignum] = trans_unboxed;
3668 transother[type_Ratio] = trans_boxed;
3669 transother[type_SingleFloat] = trans_unboxed;
3670 transother[type_DoubleFloat] = trans_unboxed;
3671 #ifdef type_LongFloat
3672 transother[type_LongFloat] = trans_unboxed;
3674 transother[type_Complex] = trans_boxed;
3675 #ifdef type_ComplexSingleFloat
3676 transother[type_ComplexSingleFloat] = trans_unboxed;
3678 #ifdef type_ComplexDoubleFloat
3679 transother[type_ComplexDoubleFloat] = trans_unboxed;
3681 #ifdef type_ComplexLongFloat
3682 transother[type_ComplexLongFloat] = trans_unboxed;
3684 transother[type_SimpleArray] = trans_boxed_large;
3685 transother[type_SimpleString] = trans_string;
3686 transother[type_SimpleBitVector] = trans_vector_bit;
3687 transother[type_SimpleVector] = trans_vector;
3688 transother[type_SimpleArrayUnsignedByte2] = trans_vector_unsigned_byte_2;
3689 transother[type_SimpleArrayUnsignedByte4] = trans_vector_unsigned_byte_4;
3690 transother[type_SimpleArrayUnsignedByte8] = trans_vector_unsigned_byte_8;
3691 transother[type_SimpleArrayUnsignedByte16] = trans_vector_unsigned_byte_16;
3692 transother[type_SimpleArrayUnsignedByte32] = trans_vector_unsigned_byte_32;
3693 #ifdef type_SimpleArraySignedByte8
3694 transother[type_SimpleArraySignedByte8] = trans_vector_unsigned_byte_8;
3696 #ifdef type_SimpleArraySignedByte16
3697 transother[type_SimpleArraySignedByte16] = trans_vector_unsigned_byte_16;
3699 #ifdef type_SimpleArraySignedByte30
3700 transother[type_SimpleArraySignedByte30] = trans_vector_unsigned_byte_32;
3702 #ifdef type_SimpleArraySignedByte32
3703 transother[type_SimpleArraySignedByte32] = trans_vector_unsigned_byte_32;
3705 transother[type_SimpleArraySingleFloat] = trans_vector_single_float;
3706 transother[type_SimpleArrayDoubleFloat] = trans_vector_double_float;
3707 #ifdef type_SimpleArrayLongFloat
3708 transother[type_SimpleArrayLongFloat] = trans_vector_long_float;
3710 #ifdef type_SimpleArrayComplexSingleFloat
3711 transother[type_SimpleArrayComplexSingleFloat] = trans_vector_complex_single_float;
3713 #ifdef type_SimpleArrayComplexDoubleFloat
3714 transother[type_SimpleArrayComplexDoubleFloat] = trans_vector_complex_double_float;
3716 #ifdef type_SimpleArrayComplexLongFloat
3717 transother[type_SimpleArrayComplexLongFloat] = trans_vector_complex_long_float;
3719 transother[type_ComplexString] = trans_boxed;
3720 transother[type_ComplexBitVector] = trans_boxed;
3721 transother[type_ComplexVector] = trans_boxed;
3722 transother[type_ComplexArray] = trans_boxed;
3723 transother[type_CodeHeader] = trans_code_header;
3724 transother[type_FunctionHeader] = trans_function_header;
3725 transother[type_ClosureFunctionHeader] = trans_function_header;
3726 transother[type_ReturnPcHeader] = trans_return_pc_header;
3727 transother[type_ClosureHeader] = trans_boxed;
3728 transother[type_FuncallableInstanceHeader] = trans_boxed;
3729 transother[type_ByteCodeFunction] = trans_boxed;
3730 transother[type_ByteCodeClosure] = trans_boxed;
3731 transother[type_ValueCellHeader] = trans_boxed;
3732 transother[type_SymbolHeader] = trans_boxed;
3733 transother[type_BaseChar] = trans_immediate;
3734 transother[type_Sap] = trans_unboxed;
3735 transother[type_UnboundMarker] = trans_immediate;
3736 transother[type_WeakPointer] = trans_weak_pointer;
3737 transother[type_InstanceHeader] = trans_boxed;
3738 transother[type_Fdefn] = trans_boxed;
3740 /* size table, initialized the same way as scavtab */
3741 for (i = 0; i < 256; i++)
3742 sizetab[i] = size_lose;
3743 for (i = 0; i < 32; i++) {
3744 sizetab[type_EvenFixnum|(i<<3)] = size_immediate;
3745 sizetab[type_FunctionPointer|(i<<3)] = size_pointer;
3746 /* OtherImmediate0 */
3747 sizetab[type_ListPointer|(i<<3)] = size_pointer;
3748 sizetab[type_OddFixnum|(i<<3)] = size_immediate;
3749 sizetab[type_InstancePointer|(i<<3)] = size_pointer;
3750 /* OtherImmediate1 */
3751 sizetab[type_OtherPointer|(i<<3)] = size_pointer;
3753 sizetab[type_Bignum] = size_unboxed;
3754 sizetab[type_Ratio] = size_boxed;
3755 sizetab[type_SingleFloat] = size_unboxed;
3756 sizetab[type_DoubleFloat] = size_unboxed;
3757 #ifdef type_LongFloat
3758 sizetab[type_LongFloat] = size_unboxed;
3760 sizetab[type_Complex] = size_boxed;
3761 #ifdef type_ComplexSingleFloat
3762 sizetab[type_ComplexSingleFloat] = size_unboxed;
3764 #ifdef type_ComplexDoubleFloat
3765 sizetab[type_ComplexDoubleFloat] = size_unboxed;
3767 #ifdef type_ComplexLongFloat
3768 sizetab[type_ComplexLongFloat] = size_unboxed;
3770 sizetab[type_SimpleArray] = size_boxed;
3771 sizetab[type_SimpleString] = size_string;
3772 sizetab[type_SimpleBitVector] = size_vector_bit;
3773 sizetab[type_SimpleVector] = size_vector;
3774 sizetab[type_SimpleArrayUnsignedByte2] = size_vector_unsigned_byte_2;
3775 sizetab[type_SimpleArrayUnsignedByte4] = size_vector_unsigned_byte_4;
3776 sizetab[type_SimpleArrayUnsignedByte8] = size_vector_unsigned_byte_8;
3777 sizetab[type_SimpleArrayUnsignedByte16] = size_vector_unsigned_byte_16;
3778 sizetab[type_SimpleArrayUnsignedByte32] = size_vector_unsigned_byte_32;
3779 #ifdef type_SimpleArraySignedByte8
3780 sizetab[type_SimpleArraySignedByte8] = size_vector_unsigned_byte_8;
3782 #ifdef type_SimpleArraySignedByte16
3783 sizetab[type_SimpleArraySignedByte16] = size_vector_unsigned_byte_16;
3785 #ifdef type_SimpleArraySignedByte30
3786 sizetab[type_SimpleArraySignedByte30] = size_vector_unsigned_byte_32;
3788 #ifdef type_SimpleArraySignedByte32
3789 sizetab[type_SimpleArraySignedByte32] = size_vector_unsigned_byte_32;
3791 sizetab[type_SimpleArraySingleFloat] = size_vector_single_float;
3792 sizetab[type_SimpleArrayDoubleFloat] = size_vector_double_float;
3793 #ifdef type_SimpleArrayLongFloat
3794 sizetab[type_SimpleArrayLongFloat] = size_vector_long_float;
3796 #ifdef type_SimpleArrayComplexSingleFloat
3797 sizetab[type_SimpleArrayComplexSingleFloat] = size_vector_complex_single_float;
3799 #ifdef type_SimpleArrayComplexDoubleFloat
3800 sizetab[type_SimpleArrayComplexDoubleFloat] = size_vector_complex_double_float;
3802 #ifdef type_SimpleArrayComplexLongFloat
3803 sizetab[type_SimpleArrayComplexLongFloat] = size_vector_complex_long_float;
3805 sizetab[type_ComplexString] = size_boxed;
3806 sizetab[type_ComplexBitVector] = size_boxed;
3807 sizetab[type_ComplexVector] = size_boxed;
3808 sizetab[type_ComplexArray] = size_boxed;
3809 sizetab[type_CodeHeader] = size_code_header;
3811 /* We shouldn't see these, so just lose if it happens. */
3812 sizetab[type_FunctionHeader] = size_function_header;
3813 sizetab[type_ClosureFunctionHeader] = size_function_header;
3814 sizetab[type_ReturnPcHeader] = size_return_pc_header;
3816 sizetab[type_ClosureHeader] = size_boxed;
3817 sizetab[type_FuncallableInstanceHeader] = size_boxed;
3818 sizetab[type_ValueCellHeader] = size_boxed;
3819 sizetab[type_SymbolHeader] = size_boxed;
3820 sizetab[type_BaseChar] = size_immediate;
3821 sizetab[type_Sap] = size_unboxed;
3822 sizetab[type_UnboundMarker] = size_immediate;
3823 sizetab[type_WeakPointer] = size_weak_pointer;
3824 sizetab[type_InstanceHeader] = size_boxed;
3825 sizetab[type_Fdefn] = size_boxed;
3828 /* Scan an area looking for an object which encloses the given pointer.
3829 * Return the object start on success or NULL on failure. */
3831 search_space(lispobj *start, size_t words, lispobj *pointer)
3835 lispobj thing = *start;
3837 /* If thing is an immediate then this is a cons. */
3838 if (is_lisp_pointer(thing)
3839 || ((thing & 3) == 0) /* fixnum */
3840 || (TypeOf(thing) == type_BaseChar)
3841 || (TypeOf(thing) == type_UnboundMarker))
3844 count = (sizetab[TypeOf(thing)])(start);
3846 /* Check whether the pointer is within this object. */
3847 if ((pointer >= start) && (pointer < (start+count))) {
3849 /*FSHOW((stderr,"/found %x in %x %x\n", pointer, start, thing));*/
3853 /* Round up the count. */
3854 count = CEILING(count,2);
3863 search_read_only_space(lispobj *pointer)
3865 lispobj* start = (lispobj*)READ_ONLY_SPACE_START;
3866 lispobj* end = (lispobj*)SymbolValue(READ_ONLY_SPACE_FREE_POINTER);
3867 if ((pointer < start) || (pointer >= end))
3869 return (search_space(start, (pointer+2)-start, pointer));
3873 search_static_space(lispobj *pointer)
3875 lispobj* start = (lispobj*)STATIC_SPACE_START;
3876 lispobj* end = (lispobj*)SymbolValue(STATIC_SPACE_FREE_POINTER);
3877 if ((pointer < start) || (pointer >= end))
3879 return (search_space(start, (pointer+2)-start, pointer));
3882 /* a faster version for searching the dynamic space. This will work even
3883 * if the object is in a current allocation region. */
3885 search_dynamic_space(lispobj *pointer)
3887 int page_index = find_page_index(pointer);
3890 /* The address may be invalid, so do some checks. */
3891 if ((page_index == -1) || (page_table[page_index].allocated == FREE_PAGE))
3893 start = (lispobj *)((void *)page_address(page_index)
3894 + page_table[page_index].first_object_offset);
3895 return (search_space(start, (pointer+2)-start, pointer));
3898 /* Is there any possibility that pointer is a valid Lisp object
3899 * reference, and/or something else (e.g. subroutine call return
3900 * address) which should prevent us from moving the referred-to thing? */
3902 possibly_valid_dynamic_space_pointer(lispobj *pointer)
3904 lispobj *start_addr;
3906 /* Find the object start address. */
3907 if ((start_addr = search_dynamic_space(pointer)) == NULL) {
3911 /* We need to allow raw pointers into Code objects for return
3912 * addresses. This will also pick up pointers to functions in code
3914 if (TypeOf(*start_addr) == type_CodeHeader) {
3915 /* XXX could do some further checks here */
3919 /* If it's not a return address then it needs to be a valid Lisp
3921 if (!is_lisp_pointer((lispobj)pointer)) {
3925 /* Check that the object pointed to is consistent with the pointer
3928 * FIXME: It's not safe to rely on the result from this check
3929 * before an object is initialized. Thus, if we were interrupted
3930 * just as an object had been allocated but not initialized, the
3931 * GC relying on this result could bogusly reclaim the memory.
3932 * However, we can't really afford to do without this check. So
3933 * we should make it safe somehow.
3934 * (1) Perhaps just review the code to make sure
3935 * that WITHOUT-GCING or WITHOUT-INTERRUPTS or some such
3936 * thing is wrapped around critical sections where allocated
3937 * memory type bits haven't been set.
3938 * (2) Perhaps find some other hack to protect against this, e.g.
3939 * recording the result of the last call to allocate-lisp-memory,
3940 * and returning true from this function when *pointer is
3941 * a reference to that result. */
3942 switch (LowtagOf((lispobj)pointer)) {
3943 case type_FunctionPointer:
3944 /* Start_addr should be the enclosing code object, or a closure
3946 switch (TypeOf(*start_addr)) {
3947 case type_CodeHeader:
3948 /* This case is probably caught above. */
3950 case type_ClosureHeader:
3951 case type_FuncallableInstanceHeader:
3952 case type_ByteCodeFunction:
3953 case type_ByteCodeClosure:
3954 if ((unsigned)pointer !=
3955 ((unsigned)start_addr+type_FunctionPointer)) {
3959 pointer, start_addr, *start_addr));
3967 pointer, start_addr, *start_addr));
3971 case type_ListPointer:
3972 if ((unsigned)pointer !=
3973 ((unsigned)start_addr+type_ListPointer)) {
3977 pointer, start_addr, *start_addr));
3980 /* Is it plausible cons? */
3981 if ((is_lisp_pointer(start_addr[0])
3982 || ((start_addr[0] & 3) == 0) /* fixnum */
3983 || (TypeOf(start_addr[0]) == type_BaseChar)
3984 || (TypeOf(start_addr[0]) == type_UnboundMarker))
3985 && (is_lisp_pointer(start_addr[1])
3986 || ((start_addr[1] & 3) == 0) /* fixnum */
3987 || (TypeOf(start_addr[1]) == type_BaseChar)
3988 || (TypeOf(start_addr[1]) == type_UnboundMarker)))
3994 pointer, start_addr, *start_addr));
3997 case type_InstancePointer:
3998 if ((unsigned)pointer !=
3999 ((unsigned)start_addr+type_InstancePointer)) {
4003 pointer, start_addr, *start_addr));
4006 if (TypeOf(start_addr[0]) != type_InstanceHeader) {
4010 pointer, start_addr, *start_addr));
4014 case type_OtherPointer:
4015 if ((unsigned)pointer !=
4016 ((int)start_addr+type_OtherPointer)) {
4020 pointer, start_addr, *start_addr));
4023 /* Is it plausible? Not a cons. XXX should check the headers. */
4024 if (is_lisp_pointer(start_addr[0]) || ((start_addr[0] & 3) == 0)) {
4028 pointer, start_addr, *start_addr));
4031 switch (TypeOf(start_addr[0])) {
4032 case type_UnboundMarker:
4037 pointer, start_addr, *start_addr));
4040 /* only pointed to by function pointers? */
4041 case type_ClosureHeader:
4042 case type_FuncallableInstanceHeader:
4043 case type_ByteCodeFunction:
4044 case type_ByteCodeClosure:
4048 pointer, start_addr, *start_addr));
4051 case type_InstanceHeader:
4055 pointer, start_addr, *start_addr));
4058 /* the valid other immediate pointer objects */
4059 case type_SimpleVector:
4062 #ifdef type_ComplexSingleFloat
4063 case type_ComplexSingleFloat:
4065 #ifdef type_ComplexDoubleFloat
4066 case type_ComplexDoubleFloat:
4068 #ifdef type_ComplexLongFloat
4069 case type_ComplexLongFloat:
4071 case type_SimpleArray:
4072 case type_ComplexString:
4073 case type_ComplexBitVector:
4074 case type_ComplexVector:
4075 case type_ComplexArray:
4076 case type_ValueCellHeader:
4077 case type_SymbolHeader:
4079 case type_CodeHeader:
4081 case type_SingleFloat:
4082 case type_DoubleFloat:
4083 #ifdef type_LongFloat
4084 case type_LongFloat:
4086 case type_SimpleString:
4087 case type_SimpleBitVector:
4088 case type_SimpleArrayUnsignedByte2:
4089 case type_SimpleArrayUnsignedByte4:
4090 case type_SimpleArrayUnsignedByte8:
4091 case type_SimpleArrayUnsignedByte16:
4092 case type_SimpleArrayUnsignedByte32:
4093 #ifdef type_SimpleArraySignedByte8
4094 case type_SimpleArraySignedByte8:
4096 #ifdef type_SimpleArraySignedByte16
4097 case type_SimpleArraySignedByte16:
4099 #ifdef type_SimpleArraySignedByte30
4100 case type_SimpleArraySignedByte30:
4102 #ifdef type_SimpleArraySignedByte32
4103 case type_SimpleArraySignedByte32:
4105 case type_SimpleArraySingleFloat:
4106 case type_SimpleArrayDoubleFloat:
4107 #ifdef type_SimpleArrayLongFloat
4108 case type_SimpleArrayLongFloat:
4110 #ifdef type_SimpleArrayComplexSingleFloat
4111 case type_SimpleArrayComplexSingleFloat:
4113 #ifdef type_SimpleArrayComplexDoubleFloat
4114 case type_SimpleArrayComplexDoubleFloat:
4116 #ifdef type_SimpleArrayComplexLongFloat
4117 case type_SimpleArrayComplexLongFloat:
4120 case type_WeakPointer:
4127 pointer, start_addr, *start_addr));
4135 pointer, start_addr, *start_addr));
4143 /* Adjust large bignum and vector objects. This will adjust the
4144 * allocated region if the size has shrunk, and move unboxed objects
4145 * into unboxed pages. The pages are not promoted here, and the
4146 * promoted region is not added to the new_regions; this is really
4147 * only designed to be called from preserve_pointer(). Shouldn't fail
4148 * if this is missed, just may delay the moving of objects to unboxed
4149 * pages, and the freeing of pages. */
4151 maybe_adjust_large_object(lispobj *where)
4156 int remaining_bytes;
4163 /* Check whether it's a vector or bignum object. */
4164 switch (TypeOf(where[0])) {
4165 case type_SimpleVector:
4169 case type_SimpleString:
4170 case type_SimpleBitVector:
4171 case type_SimpleArrayUnsignedByte2:
4172 case type_SimpleArrayUnsignedByte4:
4173 case type_SimpleArrayUnsignedByte8:
4174 case type_SimpleArrayUnsignedByte16:
4175 case type_SimpleArrayUnsignedByte32:
4176 #ifdef type_SimpleArraySignedByte8
4177 case type_SimpleArraySignedByte8:
4179 #ifdef type_SimpleArraySignedByte16
4180 case type_SimpleArraySignedByte16:
4182 #ifdef type_SimpleArraySignedByte30
4183 case type_SimpleArraySignedByte30:
4185 #ifdef type_SimpleArraySignedByte32
4186 case type_SimpleArraySignedByte32:
4188 case type_SimpleArraySingleFloat:
4189 case type_SimpleArrayDoubleFloat:
4190 #ifdef type_SimpleArrayLongFloat
4191 case type_SimpleArrayLongFloat:
4193 #ifdef type_SimpleArrayComplexSingleFloat
4194 case type_SimpleArrayComplexSingleFloat:
4196 #ifdef type_SimpleArrayComplexDoubleFloat
4197 case type_SimpleArrayComplexDoubleFloat:
4199 #ifdef type_SimpleArrayComplexLongFloat
4200 case type_SimpleArrayComplexLongFloat:
4202 boxed = UNBOXED_PAGE;
4208 /* Find its current size. */
4209 nwords = (sizetab[TypeOf(where[0])])(where);
4211 first_page = find_page_index((void *)where);
4212 gc_assert(first_page >= 0);
4214 /* Note: Any page write-protection must be removed, else a later
4215 * scavenge_newspace may incorrectly not scavenge these pages.
4216 * This would not be necessary if they are added to the new areas,
4217 * but lets do it for them all (they'll probably be written
4220 gc_assert(page_table[first_page].first_object_offset == 0);
4222 next_page = first_page;
4223 remaining_bytes = nwords*4;
4224 while (remaining_bytes > 4096) {
4225 gc_assert(page_table[next_page].gen == from_space);
4226 gc_assert((page_table[next_page].allocated == BOXED_PAGE)
4227 || (page_table[next_page].allocated == UNBOXED_PAGE));
4228 gc_assert(page_table[next_page].large_object);
4229 gc_assert(page_table[next_page].first_object_offset ==
4230 -4096*(next_page-first_page));
4231 gc_assert(page_table[next_page].bytes_used == 4096);
4233 page_table[next_page].allocated = boxed;
4235 /* Shouldn't be write-protected at this stage. Essential that the
4237 gc_assert(!page_table[next_page].write_protected);
4238 remaining_bytes -= 4096;
4242 /* Now only one page remains, but the object may have shrunk so
4243 * there may be more unused pages which will be freed. */
4245 /* Object may have shrunk but shouldn't have grown - check. */
4246 gc_assert(page_table[next_page].bytes_used >= remaining_bytes);
4248 page_table[next_page].allocated = boxed;
4249 gc_assert(page_table[next_page].allocated ==
4250 page_table[first_page].allocated);
4252 /* Adjust the bytes_used. */
4253 old_bytes_used = page_table[next_page].bytes_used;
4254 page_table[next_page].bytes_used = remaining_bytes;
4256 bytes_freed = old_bytes_used - remaining_bytes;
4258 /* Free any remaining pages; needs care. */
4260 while ((old_bytes_used == 4096) &&
4261 (page_table[next_page].gen == from_space) &&
4262 ((page_table[next_page].allocated == UNBOXED_PAGE)
4263 || (page_table[next_page].allocated == BOXED_PAGE)) &&
4264 page_table[next_page].large_object &&
4265 (page_table[next_page].first_object_offset ==
4266 -(next_page - first_page)*4096)) {
4267 /* It checks out OK, free the page. We don't need to both zeroing
4268 * pages as this should have been done before shrinking the
4269 * object. These pages shouldn't be write protected as they
4270 * should be zero filled. */
4271 gc_assert(page_table[next_page].write_protected == 0);
4273 old_bytes_used = page_table[next_page].bytes_used;
4274 page_table[next_page].allocated = FREE_PAGE;
4275 page_table[next_page].bytes_used = 0;
4276 bytes_freed += old_bytes_used;
4280 if ((bytes_freed > 0) && gencgc_verbose) {
4282 "/maybe_adjust_large_object() freed %d\n",
4286 generations[from_space].bytes_allocated -= bytes_freed;
4287 bytes_allocated -= bytes_freed;
4292 /* Take a possible pointer to a Lisp object and mark its page in the
4293 * page_table so that it will not be relocated during a GC.
4295 * This involves locating the page it points to, then backing up to
4296 * the first page that has its first object start at offset 0, and
4297 * then marking all pages dont_move from the first until a page that
4298 * ends by being full, or having free gen.
4300 * This ensures that objects spanning pages are not broken.
4302 * It is assumed that all the page static flags have been cleared at
4303 * the start of a GC.
4305 * It is also assumed that the current gc_alloc() region has been
4306 * flushed and the tables updated. */
4308 preserve_pointer(void *addr)
4310 int addr_page_index = find_page_index(addr);
4313 unsigned region_allocation;
4315 /* quick check 1: Address is quite likely to have been invalid. */
4316 if ((addr_page_index == -1)
4317 || (page_table[addr_page_index].allocated == FREE_PAGE)
4318 || (page_table[addr_page_index].bytes_used == 0)
4319 || (page_table[addr_page_index].gen != from_space)
4320 /* Skip if already marked dont_move. */
4321 || (page_table[addr_page_index].dont_move != 0))
4324 /* (Now that we know that addr_page_index is in range, it's
4325 * safe to index into page_table[] with it.) */
4326 region_allocation = page_table[addr_page_index].allocated;
4328 /* quick check 2: Check the offset within the page.
4330 * FIXME: The mask should have a symbolic name, and ideally should
4331 * be derived from page size instead of hardwired to 0xfff.
4332 * (Also fix other uses of 0xfff, elsewhere.) */
4333 if (((unsigned)addr & 0xfff) > page_table[addr_page_index].bytes_used)
4336 /* Filter out anything which can't be a pointer to a Lisp object
4337 * (or, as a special case which also requires dont_move, a return
4338 * address referring to something in a CodeObject). This is
4339 * expensive but important, since it vastly reduces the
4340 * probability that random garbage will be bogusly interpreter as
4341 * a pointer which prevents a page from moving. */
4342 if (!possibly_valid_dynamic_space_pointer(addr))
4345 /* Work backwards to find a page with a first_object_offset of 0.
4346 * The pages should be contiguous with all bytes used in the same
4347 * gen. Assumes the first_object_offset is negative or zero. */
4348 first_page = addr_page_index;
4349 while (page_table[first_page].first_object_offset != 0) {
4351 /* Do some checks. */
4352 gc_assert(page_table[first_page].bytes_used == 4096);
4353 gc_assert(page_table[first_page].gen == from_space);
4354 gc_assert(page_table[first_page].allocated == region_allocation);
4357 /* Adjust any large objects before promotion as they won't be
4358 * copied after promotion. */
4359 if (page_table[first_page].large_object) {
4360 maybe_adjust_large_object(page_address(first_page));
4361 /* If a large object has shrunk then addr may now point to a
4362 * free area in which case it's ignored here. Note it gets
4363 * through the valid pointer test above because the tail looks
4365 if ((page_table[addr_page_index].allocated == FREE_PAGE)
4366 || (page_table[addr_page_index].bytes_used == 0)
4367 /* Check the offset within the page. */
4368 || (((unsigned)addr & 0xfff)
4369 > page_table[addr_page_index].bytes_used)) {
4371 "weird? ignore ptr 0x%x to freed area of large object\n",
4375 /* It may have moved to unboxed pages. */
4376 region_allocation = page_table[first_page].allocated;
4379 /* Now work forward until the end of this contiguous area is found,
4380 * marking all pages as dont_move. */
4381 for (i = first_page; ;i++) {
4382 gc_assert(page_table[i].allocated == region_allocation);
4384 /* Mark the page static. */
4385 page_table[i].dont_move = 1;
4387 /* Move the page to the new_space. XX I'd rather not do this
4388 * but the GC logic is not quite able to copy with the static
4389 * pages remaining in the from space. This also requires the
4390 * generation bytes_allocated counters be updated. */
4391 page_table[i].gen = new_space;
4392 generations[new_space].bytes_allocated += page_table[i].bytes_used;
4393 generations[from_space].bytes_allocated -= page_table[i].bytes_used;
4395 /* It is essential that the pages are not write protected as
4396 * they may have pointers into the old-space which need
4397 * scavenging. They shouldn't be write protected at this
4399 gc_assert(!page_table[i].write_protected);
4401 /* Check whether this is the last page in this contiguous block.. */
4402 if ((page_table[i].bytes_used < 4096)
4403 /* ..or it is 4096 and is the last in the block */
4404 || (page_table[i+1].allocated == FREE_PAGE)
4405 || (page_table[i+1].bytes_used == 0) /* next page free */
4406 || (page_table[i+1].gen != from_space) /* diff. gen */
4407 || (page_table[i+1].first_object_offset == 0))
4411 /* Check that the page is now static. */
4412 gc_assert(page_table[addr_page_index].dont_move != 0);
4415 /* If the given page is not write-protected, then scan it for pointers
4416 * to younger generations or the top temp. generation, if no
4417 * suspicious pointers are found then the page is write-protected.
4419 * Care is taken to check for pointers to the current gc_alloc()
4420 * region if it is a younger generation or the temp. generation. This
4421 * frees the caller from doing a gc_alloc_update_page_tables(). Actually
4422 * the gc_alloc_generation does not need to be checked as this is only
4423 * called from scavenge_generation() when the gc_alloc generation is
4424 * younger, so it just checks if there is a pointer to the current
4427 * We return 1 if the page was write-protected, else 0. */
4429 update_page_write_prot(int page)
4431 int gen = page_table[page].gen;
4434 void **page_addr = (void **)page_address(page);
4435 int num_words = page_table[page].bytes_used / 4;
4437 /* Shouldn't be a free page. */
4438 gc_assert(page_table[page].allocated != FREE_PAGE);
4439 gc_assert(page_table[page].bytes_used != 0);
4441 /* Skip if it's already write-protected or an unboxed page. */
4442 if (page_table[page].write_protected
4443 || (page_table[page].allocated == UNBOXED_PAGE))
4446 /* Scan the page for pointers to younger generations or the
4447 * top temp. generation. */
4449 for (j = 0; j < num_words; j++) {
4450 void *ptr = *(page_addr+j);
4451 int index = find_page_index(ptr);
4453 /* Check that it's in the dynamic space */
4455 if (/* Does it point to a younger or the temp. generation? */
4456 ((page_table[index].allocated != FREE_PAGE)
4457 && (page_table[index].bytes_used != 0)
4458 && ((page_table[index].gen < gen)
4459 || (page_table[index].gen == NUM_GENERATIONS)))
4461 /* Or does it point within a current gc_alloc() region? */
4462 || ((boxed_region.start_addr <= ptr)
4463 && (ptr <= boxed_region.free_pointer))
4464 || ((unboxed_region.start_addr <= ptr)
4465 && (ptr <= unboxed_region.free_pointer))) {
4472 /* Write-protect the page. */
4473 /*FSHOW((stderr, "/write-protecting page %d gen %d\n", page, gen));*/
4475 os_protect((void *)page_addr,
4477 OS_VM_PROT_READ|OS_VM_PROT_EXECUTE);
4479 /* Note the page as protected in the page tables. */
4480 page_table[page].write_protected = 1;
4486 /* Scavenge a generation.
4488 * This will not resolve all pointers when generation is the new
4489 * space, as new objects may be added which are not check here - use
4490 * scavenge_newspace generation.
4492 * Write-protected pages should not have any pointers to the
4493 * from_space so do need scavenging; thus write-protected pages are
4494 * not always scavenged. There is some code to check that these pages
4495 * are not written; but to check fully the write-protected pages need
4496 * to be scavenged by disabling the code to skip them.
4498 * Under the current scheme when a generation is GCed the younger
4499 * generations will be empty. So, when a generation is being GCed it
4500 * is only necessary to scavenge the older generations for pointers
4501 * not the younger. So a page that does not have pointers to younger
4502 * generations does not need to be scavenged.
4504 * The write-protection can be used to note pages that don't have
4505 * pointers to younger pages. But pages can be written without having
4506 * pointers to younger generations. After the pages are scavenged here
4507 * they can be scanned for pointers to younger generations and if
4508 * there are none the page can be write-protected.
4510 * One complication is when the newspace is the top temp. generation.
4512 * Enabling SC_GEN_CK scavenges the write-protected pages and checks
4513 * that none were written, which they shouldn't be as they should have
4514 * no pointers to younger generations. This breaks down for weak
4515 * pointers as the objects contain a link to the next and are written
4516 * if a weak pointer is scavenged. Still it's a useful check. */
4518 scavenge_generation(int generation)
4525 /* Clear the write_protected_cleared flags on all pages. */
4526 for (i = 0; i < NUM_PAGES; i++)
4527 page_table[i].write_protected_cleared = 0;
4530 for (i = 0; i < last_free_page; i++) {
4531 if ((page_table[i].allocated == BOXED_PAGE)
4532 && (page_table[i].bytes_used != 0)
4533 && (page_table[i].gen == generation)) {
4536 /* This should be the start of a contiguous block. */
4537 gc_assert(page_table[i].first_object_offset == 0);
4539 /* We need to find the full extent of this contiguous
4540 * block in case objects span pages. */
4542 /* Now work forward until the end of this contiguous area
4543 * is found. A small area is preferred as there is a
4544 * better chance of its pages being write-protected. */
4545 for (last_page = i; ; last_page++)
4546 /* Check whether this is the last page in this contiguous
4548 if ((page_table[last_page].bytes_used < 4096)
4549 /* Or it is 4096 and is the last in the block */
4550 || (page_table[last_page+1].allocated != BOXED_PAGE)
4551 || (page_table[last_page+1].bytes_used == 0)
4552 || (page_table[last_page+1].gen != generation)
4553 || (page_table[last_page+1].first_object_offset == 0))
4556 /* Do a limited check for write_protected pages. If all pages
4557 * are write_protected then there is no need to scavenge. */
4560 for (j = i; j <= last_page; j++)
4561 if (page_table[j].write_protected == 0) {
4569 scavenge(page_address(i), (page_table[last_page].bytes_used
4570 + (last_page-i)*4096)/4);
4572 /* Now scan the pages and write protect those
4573 * that don't have pointers to younger
4575 if (enable_page_protection) {
4576 for (j = i; j <= last_page; j++) {
4577 num_wp += update_page_write_prot(j);
4586 if ((gencgc_verbose > 1) && (num_wp != 0)) {
4588 "/write protected %d pages within generation %d\n",
4589 num_wp, generation));
4593 /* Check that none of the write_protected pages in this generation
4594 * have been written to. */
4595 for (i = 0; i < NUM_PAGES; i++) {
4596 if ((page_table[i].allocation ! =FREE_PAGE)
4597 && (page_table[i].bytes_used != 0)
4598 && (page_table[i].gen == generation)
4599 && (page_table[i].write_protected_cleared != 0)) {
4600 FSHOW((stderr, "/scavenge_generation() %d\n", generation));
4602 "/page bytes_used=%d first_object_offset=%d dont_move=%d\n",
4603 page_table[i].bytes_used,
4604 page_table[i].first_object_offset,
4605 page_table[i].dont_move));
4606 lose("write to protected page %d in scavenge_generation()", i);
4613 /* Scavenge a newspace generation. As it is scavenged new objects may
4614 * be allocated to it; these will also need to be scavenged. This
4615 * repeats until there are no more objects unscavenged in the
4616 * newspace generation.
4618 * To help improve the efficiency, areas written are recorded by
4619 * gc_alloc() and only these scavenged. Sometimes a little more will be
4620 * scavenged, but this causes no harm. An easy check is done that the
4621 * scavenged bytes equals the number allocated in the previous
4624 * Write-protected pages are not scanned except if they are marked
4625 * dont_move in which case they may have been promoted and still have
4626 * pointers to the from space.
4628 * Write-protected pages could potentially be written by alloc however
4629 * to avoid having to handle re-scavenging of write-protected pages
4630 * gc_alloc() does not write to write-protected pages.
4632 * New areas of objects allocated are recorded alternatively in the two
4633 * new_areas arrays below. */
4634 static struct new_area new_areas_1[NUM_NEW_AREAS];
4635 static struct new_area new_areas_2[NUM_NEW_AREAS];
4637 /* Do one full scan of the new space generation. This is not enough to
4638 * complete the job as new objects may be added to the generation in
4639 * the process which are not scavenged. */
4641 scavenge_newspace_generation_one_scan(int generation)
4646 "/starting one full scan of newspace generation %d\n",
4649 for (i = 0; i < last_free_page; i++) {
4650 if ((page_table[i].allocated == BOXED_PAGE)
4651 && (page_table[i].bytes_used != 0)
4652 && (page_table[i].gen == generation)
4653 && ((page_table[i].write_protected == 0)
4654 /* (This may be redundant as write_protected is now
4655 * cleared before promotion.) */
4656 || (page_table[i].dont_move == 1))) {
4659 /* The scavenge will start at the first_object_offset of page i.
4661 * We need to find the full extent of this contiguous
4662 * block in case objects span pages.
4664 * Now work forward until the end of this contiguous area
4665 * is found. A small area is preferred as there is a
4666 * better chance of its pages being write-protected. */
4667 for (last_page = i; ;last_page++) {
4668 /* Check whether this is the last page in this
4669 * contiguous block */
4670 if ((page_table[last_page].bytes_used < 4096)
4671 /* Or it is 4096 and is the last in the block */
4672 || (page_table[last_page+1].allocated != BOXED_PAGE)
4673 || (page_table[last_page+1].bytes_used == 0)
4674 || (page_table[last_page+1].gen != generation)
4675 || (page_table[last_page+1].first_object_offset == 0))
4679 /* Do a limited check for write-protected pages. If all
4680 * pages are write-protected then no need to scavenge,
4681 * except if the pages are marked dont_move. */
4684 for (j = i; j <= last_page; j++)
4685 if ((page_table[j].write_protected == 0)
4686 || (page_table[j].dont_move != 0)) {
4694 /* Calculate the size. */
4696 size = (page_table[last_page].bytes_used
4697 - page_table[i].first_object_offset)/4;
4699 size = (page_table[last_page].bytes_used
4700 + (last_page-i)*4096
4701 - page_table[i].first_object_offset)/4;
4704 new_areas_ignore_page = last_page;
4706 scavenge(page_address(i) +
4707 page_table[i].first_object_offset,
4718 "/done with one full scan of newspace generation %d\n",
4722 /* Do a complete scavenge of the newspace generation. */
4724 scavenge_newspace_generation(int generation)
4728 /* the new_areas array currently being written to by gc_alloc() */
4729 struct new_area (*current_new_areas)[] = &new_areas_1;
4730 int current_new_areas_index;
4732 /* the new_areas created but the previous scavenge cycle */
4733 struct new_area (*previous_new_areas)[] = NULL;
4734 int previous_new_areas_index;
4736 /* Flush the current regions updating the tables. */
4737 gc_alloc_update_page_tables(0, &boxed_region);
4738 gc_alloc_update_page_tables(1, &unboxed_region);
4740 /* Turn on the recording of new areas by gc_alloc(). */
4741 new_areas = current_new_areas;
4742 new_areas_index = 0;
4744 /* Don't need to record new areas that get scavenged anyway during
4745 * scavenge_newspace_generation_one_scan. */
4746 record_new_objects = 1;
4748 /* Start with a full scavenge. */
4749 scavenge_newspace_generation_one_scan(generation);
4751 /* Record all new areas now. */
4752 record_new_objects = 2;
4754 /* Flush the current regions updating the tables. */
4755 gc_alloc_update_page_tables(0, &boxed_region);
4756 gc_alloc_update_page_tables(1, &unboxed_region);
4758 /* Grab new_areas_index. */
4759 current_new_areas_index = new_areas_index;
4762 "The first scan is finished; current_new_areas_index=%d.\n",
4763 current_new_areas_index));*/
4765 while (current_new_areas_index > 0) {
4766 /* Move the current to the previous new areas */
4767 previous_new_areas = current_new_areas;
4768 previous_new_areas_index = current_new_areas_index;
4770 /* Scavenge all the areas in previous new areas. Any new areas
4771 * allocated are saved in current_new_areas. */
4773 /* Allocate an array for current_new_areas; alternating between
4774 * new_areas_1 and 2 */
4775 if (previous_new_areas == &new_areas_1)
4776 current_new_areas = &new_areas_2;
4778 current_new_areas = &new_areas_1;
4780 /* Set up for gc_alloc(). */
4781 new_areas = current_new_areas;
4782 new_areas_index = 0;
4784 /* Check whether previous_new_areas had overflowed. */
4785 if (previous_new_areas_index >= NUM_NEW_AREAS) {
4787 /* New areas of objects allocated have been lost so need to do a
4788 * full scan to be sure! If this becomes a problem try
4789 * increasing NUM_NEW_AREAS. */
4791 SHOW("new_areas overflow, doing full scavenge");
4793 /* Don't need to record new areas that get scavenge anyway
4794 * during scavenge_newspace_generation_one_scan. */
4795 record_new_objects = 1;
4797 scavenge_newspace_generation_one_scan(generation);
4799 /* Record all new areas now. */
4800 record_new_objects = 2;
4802 /* Flush the current regions updating the tables. */
4803 gc_alloc_update_page_tables(0, &boxed_region);
4804 gc_alloc_update_page_tables(1, &unboxed_region);
4808 /* Work through previous_new_areas. */
4809 for (i = 0; i < previous_new_areas_index; i++) {
4810 /* FIXME: All these bare *4 and /4 should be something
4811 * like BYTES_PER_WORD or WBYTES. */
4812 int page = (*previous_new_areas)[i].page;
4813 int offset = (*previous_new_areas)[i].offset;
4814 int size = (*previous_new_areas)[i].size / 4;
4815 gc_assert((*previous_new_areas)[i].size % 4 == 0);
4817 scavenge(page_address(page)+offset, size);
4820 /* Flush the current regions updating the tables. */
4821 gc_alloc_update_page_tables(0, &boxed_region);
4822 gc_alloc_update_page_tables(1, &unboxed_region);
4825 current_new_areas_index = new_areas_index;
4828 "The re-scan has finished; current_new_areas_index=%d.\n",
4829 current_new_areas_index));*/
4832 /* Turn off recording of areas allocated by gc_alloc(). */
4833 record_new_objects = 0;
4836 /* Check that none of the write_protected pages in this generation
4837 * have been written to. */
4838 for (i = 0; i < NUM_PAGES; i++) {
4839 if ((page_table[i].allocation != FREE_PAGE)
4840 && (page_table[i].bytes_used != 0)
4841 && (page_table[i].gen == generation)
4842 && (page_table[i].write_protected_cleared != 0)
4843 && (page_table[i].dont_move == 0)) {
4844 lose("write protected page %d written to in scavenge_newspace_generation\ngeneration=%d dont_move=%d",
4845 i, generation, page_table[i].dont_move);
4851 /* Un-write-protect all the pages in from_space. This is done at the
4852 * start of a GC else there may be many page faults while scavenging
4853 * the newspace (I've seen drive the system time to 99%). These pages
4854 * would need to be unprotected anyway before unmapping in
4855 * free_oldspace; not sure what effect this has on paging.. */
4857 unprotect_oldspace(void)
4861 for (i = 0; i < last_free_page; i++) {
4862 if ((page_table[i].allocated != FREE_PAGE)
4863 && (page_table[i].bytes_used != 0)
4864 && (page_table[i].gen == from_space)) {
4867 page_start = (void *)page_address(i);
4869 /* Remove any write-protection. We should be able to rely
4870 * on the write-protect flag to avoid redundant calls. */
4871 if (page_table[i].write_protected) {
4872 os_protect(page_start, 4096, OS_VM_PROT_ALL);
4873 page_table[i].write_protected = 0;
4879 /* Work through all the pages and free any in from_space. This
4880 * assumes that all objects have been copied or promoted to an older
4881 * generation. Bytes_allocated and the generation bytes_allocated
4882 * counter are updated. The number of bytes freed is returned. */
4883 extern void i586_bzero(void *addr, int nbytes);
4887 int bytes_freed = 0;
4888 int first_page, last_page;
4893 /* Find a first page for the next region of pages. */
4894 while ((first_page < last_free_page)
4895 && ((page_table[first_page].allocated == FREE_PAGE)
4896 || (page_table[first_page].bytes_used == 0)
4897 || (page_table[first_page].gen != from_space)))
4900 if (first_page >= last_free_page)
4903 /* Find the last page of this region. */
4904 last_page = first_page;
4907 /* Free the page. */
4908 bytes_freed += page_table[last_page].bytes_used;
4909 generations[page_table[last_page].gen].bytes_allocated -=
4910 page_table[last_page].bytes_used;
4911 page_table[last_page].allocated = FREE_PAGE;
4912 page_table[last_page].bytes_used = 0;
4914 /* Remove any write-protection. We should be able to rely
4915 * on the write-protect flag to avoid redundant calls. */
4917 void *page_start = (void *)page_address(last_page);
4919 if (page_table[last_page].write_protected) {
4920 os_protect(page_start, 4096, OS_VM_PROT_ALL);
4921 page_table[last_page].write_protected = 0;
4926 while ((last_page < last_free_page)
4927 && (page_table[last_page].allocated != FREE_PAGE)
4928 && (page_table[last_page].bytes_used != 0)
4929 && (page_table[last_page].gen == from_space));
4931 /* Zero pages from first_page to (last_page-1).
4933 * FIXME: Why not use os_zero(..) function instead of
4934 * hand-coding this again? (Check other gencgc_unmap_zero
4936 if (gencgc_unmap_zero) {
4937 void *page_start, *addr;
4939 page_start = (void *)page_address(first_page);
4941 os_invalidate(page_start, 4096*(last_page-first_page));
4942 addr = os_validate(page_start, 4096*(last_page-first_page));
4943 if (addr == NULL || addr != page_start) {
4944 /* Is this an error condition? I couldn't really tell from
4945 * the old CMU CL code, which fprintf'ed a message with
4946 * an exclamation point at the end. But I've never seen the
4947 * message, so it must at least be unusual..
4949 * (The same condition is also tested for in gc_free_heap.)
4951 * -- WHN 19991129 */
4952 lose("i586_bzero: page moved, 0x%08x ==> 0x%08x",
4959 page_start = (int *)page_address(first_page);
4960 i586_bzero(page_start, 4096*(last_page-first_page));
4963 first_page = last_page;
4965 } while (first_page < last_free_page);
4967 bytes_allocated -= bytes_freed;
4972 /* Print some information about a pointer at the given address. */
4974 print_ptr(lispobj *addr)
4976 /* If addr is in the dynamic space then out the page information. */
4977 int pi1 = find_page_index((void*)addr);
4980 fprintf(stderr," %x: page %d alloc %d gen %d bytes_used %d offset %d dont_move %d\n",
4981 (unsigned int) addr,
4983 page_table[pi1].allocated,
4984 page_table[pi1].gen,
4985 page_table[pi1].bytes_used,
4986 page_table[pi1].first_object_offset,
4987 page_table[pi1].dont_move);
4988 fprintf(stderr," %x %x %x %x (%x) %x %x %x %x\n",
5001 extern int undefined_tramp;
5004 verify_space(lispobj *start, size_t words)
5006 int is_in_dynamic_space = (find_page_index((void*)start) != -1);
5007 int is_in_readonly_space =
5008 (READ_ONLY_SPACE_START <= (unsigned)start &&
5009 (unsigned)start < SymbolValue(READ_ONLY_SPACE_FREE_POINTER));
5013 lispobj thing = *(lispobj*)start;
5015 if (is_lisp_pointer(thing)) {
5016 int page_index = find_page_index((void*)thing);
5017 int to_readonly_space =
5018 (READ_ONLY_SPACE_START <= thing &&
5019 thing < SymbolValue(READ_ONLY_SPACE_FREE_POINTER));
5020 int to_static_space =
5021 (STATIC_SPACE_START <= thing &&
5022 thing < SymbolValue(STATIC_SPACE_FREE_POINTER));
5024 /* Does it point to the dynamic space? */
5025 if (page_index != -1) {
5026 /* If it's within the dynamic space it should point to a used
5027 * page. XX Could check the offset too. */
5028 if ((page_table[page_index].allocated != FREE_PAGE)
5029 && (page_table[page_index].bytes_used == 0))
5030 lose ("Ptr %x @ %x sees free page.", thing, start);
5031 /* Check that it doesn't point to a forwarding pointer! */
5032 if (*((lispobj *)native_pointer(thing)) == 0x01) {
5033 lose("Ptr %x @ %x sees forwarding ptr.", thing, start);
5035 /* Check that its not in the RO space as it would then be a
5036 * pointer from the RO to the dynamic space. */
5037 if (is_in_readonly_space) {
5038 lose("ptr to dynamic space %x from RO space %x",
5041 /* Does it point to a plausible object? This check slows
5042 * it down a lot (so it's commented out).
5044 * FIXME: Add a variable to enable this dynamically. */
5045 /* if (!possibly_valid_dynamic_space_pointer((lispobj *)thing)) {
5046 * lose("ptr %x to invalid object %x", thing, start); */
5048 /* Verify that it points to another valid space. */
5049 if (!to_readonly_space && !to_static_space
5050 && (thing != (unsigned)&undefined_tramp)) {
5051 lose("Ptr %x @ %x sees junk.", thing, start);
5055 if (thing & 0x3) { /* Skip fixnums. FIXME: There should be an
5056 * is_fixnum for this. */
5058 switch(TypeOf(*start)) {
5061 case type_SimpleVector:
5064 case type_SimpleArray:
5065 case type_ComplexString:
5066 case type_ComplexBitVector:
5067 case type_ComplexVector:
5068 case type_ComplexArray:
5069 case type_ClosureHeader:
5070 case type_FuncallableInstanceHeader:
5071 case type_ByteCodeFunction:
5072 case type_ByteCodeClosure:
5073 case type_ValueCellHeader:
5074 case type_SymbolHeader:
5076 case type_UnboundMarker:
5077 case type_InstanceHeader:
5082 case type_CodeHeader:
5084 lispobj object = *start;
5086 int nheader_words, ncode_words, nwords;
5088 struct function *fheaderp;
5090 code = (struct code *) start;
5092 /* Check that it's not in the dynamic space.
5093 * FIXME: Isn't is supposed to be OK for code
5094 * objects to be in the dynamic space these days? */
5095 if (is_in_dynamic_space
5096 /* It's ok if it's byte compiled code. The trace
5097 * table offset will be a fixnum if it's x86
5098 * compiled code - check.
5100 * FIXME: #^#@@! lack of abstraction here..
5101 * This line can probably go away now that
5102 * there's no byte compiler, but I've got
5103 * too much to worry about right now to try
5104 * to make sure. -- WHN 2001-10-06 */
5105 && !(code->trace_table_offset & 0x3)
5106 /* Only when enabled */
5107 && verify_dynamic_code_check) {
5109 "/code object at %x in the dynamic space\n",
5113 ncode_words = fixnum_value(code->code_size);
5114 nheader_words = HeaderValue(object);
5115 nwords = ncode_words + nheader_words;
5116 nwords = CEILING(nwords, 2);
5117 /* Scavenge the boxed section of the code data block */
5118 verify_space(start + 1, nheader_words - 1);
5120 /* Scavenge the boxed section of each function object in
5121 * the code data block. */
5122 fheaderl = code->entry_points;
5123 while (fheaderl != NIL) {
5124 fheaderp = (struct function *) native_pointer(fheaderl);
5125 gc_assert(TypeOf(fheaderp->header) == type_FunctionHeader);
5126 verify_space(&fheaderp->name, 1);
5127 verify_space(&fheaderp->arglist, 1);
5128 verify_space(&fheaderp->type, 1);
5129 fheaderl = fheaderp->next;
5135 /* unboxed objects */
5137 case type_SingleFloat:
5138 case type_DoubleFloat:
5139 #ifdef type_ComplexLongFloat
5140 case type_LongFloat:
5142 #ifdef type_ComplexSingleFloat
5143 case type_ComplexSingleFloat:
5145 #ifdef type_ComplexDoubleFloat
5146 case type_ComplexDoubleFloat:
5148 #ifdef type_ComplexLongFloat
5149 case type_ComplexLongFloat:
5151 case type_SimpleString:
5152 case type_SimpleBitVector:
5153 case type_SimpleArrayUnsignedByte2:
5154 case type_SimpleArrayUnsignedByte4:
5155 case type_SimpleArrayUnsignedByte8:
5156 case type_SimpleArrayUnsignedByte16:
5157 case type_SimpleArrayUnsignedByte32:
5158 #ifdef type_SimpleArraySignedByte8
5159 case type_SimpleArraySignedByte8:
5161 #ifdef type_SimpleArraySignedByte16
5162 case type_SimpleArraySignedByte16:
5164 #ifdef type_SimpleArraySignedByte30
5165 case type_SimpleArraySignedByte30:
5167 #ifdef type_SimpleArraySignedByte32
5168 case type_SimpleArraySignedByte32:
5170 case type_SimpleArraySingleFloat:
5171 case type_SimpleArrayDoubleFloat:
5172 #ifdef type_SimpleArrayComplexLongFloat
5173 case type_SimpleArrayLongFloat:
5175 #ifdef type_SimpleArrayComplexSingleFloat
5176 case type_SimpleArrayComplexSingleFloat:
5178 #ifdef type_SimpleArrayComplexDoubleFloat
5179 case type_SimpleArrayComplexDoubleFloat:
5181 #ifdef type_SimpleArrayComplexLongFloat
5182 case type_SimpleArrayComplexLongFloat:
5185 case type_WeakPointer:
5186 count = (sizetab[TypeOf(*start)])(start);
5202 /* FIXME: It would be nice to make names consistent so that
5203 * foo_size meant size *in* *bytes* instead of size in some
5204 * arbitrary units. (Yes, this caused a bug, how did you guess?:-)
5205 * Some counts of lispobjs are called foo_count; it might be good
5206 * to grep for all foo_size and rename the appropriate ones to
5208 int read_only_space_size =
5209 (lispobj*)SymbolValue(READ_ONLY_SPACE_FREE_POINTER)
5210 - (lispobj*)READ_ONLY_SPACE_START;
5211 int static_space_size =
5212 (lispobj*)SymbolValue(STATIC_SPACE_FREE_POINTER)
5213 - (lispobj*)STATIC_SPACE_START;
5214 int binding_stack_size =
5215 (lispobj*)SymbolValue(BINDING_STACK_POINTER)
5216 - (lispobj*)BINDING_STACK_START;
5218 verify_space((lispobj*)READ_ONLY_SPACE_START, read_only_space_size);
5219 verify_space((lispobj*)STATIC_SPACE_START , static_space_size);
5220 verify_space((lispobj*)BINDING_STACK_START , binding_stack_size);
5224 verify_generation(int generation)
5228 for (i = 0; i < last_free_page; i++) {
5229 if ((page_table[i].allocated != FREE_PAGE)
5230 && (page_table[i].bytes_used != 0)
5231 && (page_table[i].gen == generation)) {
5233 int region_allocation = page_table[i].allocated;
5235 /* This should be the start of a contiguous block */
5236 gc_assert(page_table[i].first_object_offset == 0);
5238 /* Need to find the full extent of this contiguous block in case
5239 objects span pages. */
5241 /* Now work forward until the end of this contiguous area is
5243 for (last_page = i; ;last_page++)
5244 /* Check whether this is the last page in this contiguous
5246 if ((page_table[last_page].bytes_used < 4096)
5247 /* Or it is 4096 and is the last in the block */
5248 || (page_table[last_page+1].allocated != region_allocation)
5249 || (page_table[last_page+1].bytes_used == 0)
5250 || (page_table[last_page+1].gen != generation)
5251 || (page_table[last_page+1].first_object_offset == 0))
5254 verify_space(page_address(i), (page_table[last_page].bytes_used
5255 + (last_page-i)*4096)/4);
5261 /* Check that all the free space is zero filled. */
5263 verify_zero_fill(void)
5267 for (page = 0; page < last_free_page; page++) {
5268 if (page_table[page].allocated == FREE_PAGE) {
5269 /* The whole page should be zero filled. */
5270 int *start_addr = (int *)page_address(page);
5273 for (i = 0; i < size; i++) {
5274 if (start_addr[i] != 0) {
5275 lose("free page not zero at %x", start_addr + i);
5279 int free_bytes = 4096 - page_table[page].bytes_used;
5280 if (free_bytes > 0) {
5281 int *start_addr = (int *)((unsigned)page_address(page)
5282 + page_table[page].bytes_used);
5283 int size = free_bytes / 4;
5285 for (i = 0; i < size; i++) {
5286 if (start_addr[i] != 0) {
5287 lose("free region not zero at %x", start_addr + i);
5295 /* External entry point for verify_zero_fill */
5297 gencgc_verify_zero_fill(void)
5299 /* Flush the alloc regions updating the tables. */
5300 boxed_region.free_pointer = current_region_free_pointer;
5301 gc_alloc_update_page_tables(0, &boxed_region);
5302 gc_alloc_update_page_tables(1, &unboxed_region);
5303 SHOW("verifying zero fill");
5305 current_region_free_pointer = boxed_region.free_pointer;
5306 current_region_end_addr = boxed_region.end_addr;
5310 verify_dynamic_space(void)
5314 for (i = 0; i < NUM_GENERATIONS; i++)
5315 verify_generation(i);
5317 if (gencgc_enable_verify_zero_fill)
5321 /* Write-protect all the dynamic boxed pages in the given generation. */
5323 write_protect_generation_pages(int generation)
5327 gc_assert(generation < NUM_GENERATIONS);
5329 for (i = 0; i < last_free_page; i++)
5330 if ((page_table[i].allocated == BOXED_PAGE)
5331 && (page_table[i].bytes_used != 0)
5332 && (page_table[i].gen == generation)) {
5335 page_start = (void *)page_address(i);
5337 os_protect(page_start,
5339 OS_VM_PROT_READ | OS_VM_PROT_EXECUTE);
5341 /* Note the page as protected in the page tables. */
5342 page_table[i].write_protected = 1;
5345 if (gencgc_verbose > 1) {
5347 "/write protected %d of %d pages in generation %d\n",
5348 count_write_protect_generation_pages(generation),
5349 count_generation_pages(generation),
5354 /* Garbage collect a generation. If raise is 0 then the remains of the
5355 * generation are not raised to the next generation. */
5357 garbage_collect_generation(int generation, int raise)
5359 unsigned long bytes_freed;
5361 unsigned long static_space_size;
5363 gc_assert(generation <= (NUM_GENERATIONS-1));
5365 /* The oldest generation can't be raised. */
5366 gc_assert((generation != (NUM_GENERATIONS-1)) || (raise == 0));
5368 /* Initialize the weak pointer list. */
5369 weak_pointers = NULL;
5371 /* When a generation is not being raised it is transported to a
5372 * temporary generation (NUM_GENERATIONS), and lowered when
5373 * done. Set up this new generation. There should be no pages
5374 * allocated to it yet. */
5376 gc_assert(generations[NUM_GENERATIONS].bytes_allocated == 0);
5378 /* Set the global src and dest. generations */
5379 from_space = generation;
5381 new_space = generation+1;
5383 new_space = NUM_GENERATIONS;
5385 /* Change to a new space for allocation, resetting the alloc_start_page */
5386 gc_alloc_generation = new_space;
5387 generations[new_space].alloc_start_page = 0;
5388 generations[new_space].alloc_unboxed_start_page = 0;
5389 generations[new_space].alloc_large_start_page = 0;
5390 generations[new_space].alloc_large_unboxed_start_page = 0;
5392 /* Before any pointers are preserved, the dont_move flags on the
5393 * pages need to be cleared. */
5394 for (i = 0; i < last_free_page; i++)
5395 page_table[i].dont_move = 0;
5397 /* Un-write-protect the old-space pages. This is essential for the
5398 * promoted pages as they may contain pointers into the old-space
5399 * which need to be scavenged. It also helps avoid unnecessary page
5400 * faults as forwarding pointers are written into them. They need to
5401 * be un-protected anyway before unmapping later. */
5402 unprotect_oldspace();
5404 /* Scavenge the stack's conservative roots. */
5407 for (ptr = (void **)CONTROL_STACK_END - 1;
5408 ptr > (void **)&raise;
5410 preserve_pointer(*ptr);
5415 if (gencgc_verbose > 1) {
5416 int num_dont_move_pages = count_dont_move_pages();
5418 "/non-movable pages due to conservative pointers = %d (%d bytes)\n",
5419 num_dont_move_pages,
5420 /* FIXME: 4096 should be symbolic constant here and
5421 * prob'ly elsewhere too. */
5422 num_dont_move_pages * 4096);
5426 /* Scavenge all the rest of the roots. */
5428 /* Scavenge the Lisp functions of the interrupt handlers, taking
5429 * care to avoid SIG_DFL and SIG_IGN. */
5430 for (i = 0; i < NSIG; i++) {
5431 union interrupt_handler handler = interrupt_handlers[i];
5432 if (!ARE_SAME_HANDLER(handler.c, SIG_IGN) &&
5433 !ARE_SAME_HANDLER(handler.c, SIG_DFL)) {
5434 scavenge((lispobj *)(interrupt_handlers + i), 1);
5438 /* Scavenge the binding stack. */
5439 scavenge((lispobj *) BINDING_STACK_START,
5440 (lispobj *)SymbolValue(BINDING_STACK_POINTER) -
5441 (lispobj *)BINDING_STACK_START);
5443 /* The original CMU CL code had scavenge-read-only-space code
5444 * controlled by the Lisp-level variable
5445 * *SCAVENGE-READ-ONLY-SPACE*. It was disabled by default, and it
5446 * wasn't documented under what circumstances it was useful or
5447 * safe to turn it on, so it's been turned off in SBCL. If you
5448 * want/need this functionality, and can test and document it,
5449 * please submit a patch. */
5451 if (SymbolValue(SCAVENGE_READ_ONLY_SPACE) != NIL) {
5452 unsigned long read_only_space_size =
5453 (lispobj*)SymbolValue(READ_ONLY_SPACE_FREE_POINTER) -
5454 (lispobj*)READ_ONLY_SPACE_START;
5456 "/scavenge read only space: %d bytes\n",
5457 read_only_space_size * sizeof(lispobj)));
5458 scavenge( (lispobj *) READ_ONLY_SPACE_START, read_only_space_size);
5462 /* Scavenge static space. */
5464 (lispobj *)SymbolValue(STATIC_SPACE_FREE_POINTER) -
5465 (lispobj *)STATIC_SPACE_START;
5466 if (gencgc_verbose > 1) {
5468 "/scavenge static space: %d bytes\n",
5469 static_space_size * sizeof(lispobj)));
5471 scavenge( (lispobj *) STATIC_SPACE_START, static_space_size);
5473 /* All generations but the generation being GCed need to be
5474 * scavenged. The new_space generation needs special handling as
5475 * objects may be moved in - it is handled separately below. */
5476 for (i = 0; i < NUM_GENERATIONS; i++) {
5477 if ((i != generation) && (i != new_space)) {
5478 scavenge_generation(i);
5482 /* Finally scavenge the new_space generation. Keep going until no
5483 * more objects are moved into the new generation */
5484 scavenge_newspace_generation(new_space);
5486 /* FIXME: I tried reenabling this check when debugging unrelated
5487 * GC weirdness ca. sbcl-0.6.12.45, and it failed immediately.
5488 * Since the current GC code seems to work well, I'm guessing that
5489 * this debugging code is just stale, but I haven't tried to
5490 * figure it out. It should be figured out and then either made to
5491 * work or just deleted. */
5492 #define RESCAN_CHECK 0
5494 /* As a check re-scavenge the newspace once; no new objects should
5497 int old_bytes_allocated = bytes_allocated;
5498 int bytes_allocated;
5500 /* Start with a full scavenge. */
5501 scavenge_newspace_generation_one_scan(new_space);
5503 /* Flush the current regions, updating the tables. */
5504 gc_alloc_update_page_tables(0, &boxed_region);
5505 gc_alloc_update_page_tables(1, &unboxed_region);
5507 bytes_allocated = bytes_allocated - old_bytes_allocated;
5509 if (bytes_allocated != 0) {
5510 lose("Rescan of new_space allocated %d more bytes.",
5516 scan_weak_pointers();
5518 /* Flush the current regions, updating the tables. */
5519 gc_alloc_update_page_tables(0, &boxed_region);
5520 gc_alloc_update_page_tables(1, &unboxed_region);
5522 /* Free the pages in oldspace, but not those marked dont_move. */
5523 bytes_freed = free_oldspace();
5525 /* If the GC is not raising the age then lower the generation back
5526 * to its normal generation number */
5528 for (i = 0; i < last_free_page; i++)
5529 if ((page_table[i].bytes_used != 0)
5530 && (page_table[i].gen == NUM_GENERATIONS))
5531 page_table[i].gen = generation;
5532 gc_assert(generations[generation].bytes_allocated == 0);
5533 generations[generation].bytes_allocated =
5534 generations[NUM_GENERATIONS].bytes_allocated;
5535 generations[NUM_GENERATIONS].bytes_allocated = 0;
5538 /* Reset the alloc_start_page for generation. */
5539 generations[generation].alloc_start_page = 0;
5540 generations[generation].alloc_unboxed_start_page = 0;
5541 generations[generation].alloc_large_start_page = 0;
5542 generations[generation].alloc_large_unboxed_start_page = 0;
5544 if (generation >= verify_gens) {
5548 verify_dynamic_space();
5551 /* Set the new gc trigger for the GCed generation. */
5552 generations[generation].gc_trigger =
5553 generations[generation].bytes_allocated
5554 + generations[generation].bytes_consed_between_gc;
5557 generations[generation].num_gc = 0;
5559 ++generations[generation].num_gc;
5562 /* Update last_free_page, then SymbolValue(ALLOCATION_POINTER). */
5564 update_x86_dynamic_space_free_pointer(void)
5569 for (i = 0; i < NUM_PAGES; i++)
5570 if ((page_table[i].allocated != FREE_PAGE)
5571 && (page_table[i].bytes_used != 0))
5574 last_free_page = last_page+1;
5576 SetSymbolValue(ALLOCATION_POINTER,
5577 (lispobj)(((char *)heap_base) + last_free_page*4096));
5578 return 0; /* dummy value: return something ... */
5581 /* GC all generations below last_gen, raising their objects to the
5582 * next generation until all generations below last_gen are empty.
5583 * Then if last_gen is due for a GC then GC it. In the special case
5584 * that last_gen==NUM_GENERATIONS, the last generation is always
5585 * GC'ed. The valid range for last_gen is: 0,1,...,NUM_GENERATIONS.
5587 * The oldest generation to be GCed will always be
5588 * gencgc_oldest_gen_to_gc, partly ignoring last_gen if necessary. */
5590 collect_garbage(unsigned last_gen)
5597 boxed_region.free_pointer = current_region_free_pointer;
5599 FSHOW((stderr, "/entering collect_garbage(%d)\n", last_gen));
5601 if (last_gen > NUM_GENERATIONS) {
5603 "/collect_garbage: last_gen = %d, doing a level 0 GC\n",
5608 /* Flush the alloc regions updating the tables. */
5609 gc_alloc_update_page_tables(0, &boxed_region);
5610 gc_alloc_update_page_tables(1, &unboxed_region);
5612 /* Verify the new objects created by Lisp code. */
5613 if (pre_verify_gen_0) {
5614 SHOW((stderr, "pre-checking generation 0\n"));
5615 verify_generation(0);
5618 if (gencgc_verbose > 1)
5619 print_generation_stats(0);
5622 /* Collect the generation. */
5624 if (gen >= gencgc_oldest_gen_to_gc) {
5625 /* Never raise the oldest generation. */
5630 || (generations[gen].num_gc >= generations[gen].trigger_age);
5633 if (gencgc_verbose > 1) {
5635 "starting GC of generation %d with raise=%d alloc=%d trig=%d GCs=%d\n",
5638 generations[gen].bytes_allocated,
5639 generations[gen].gc_trigger,
5640 generations[gen].num_gc));
5643 /* If an older generation is being filled, then update its
5646 generations[gen+1].cum_sum_bytes_allocated +=
5647 generations[gen+1].bytes_allocated;
5650 garbage_collect_generation(gen, raise);
5652 /* Reset the memory age cum_sum. */
5653 generations[gen].cum_sum_bytes_allocated = 0;
5655 if (gencgc_verbose > 1) {
5656 FSHOW((stderr, "GC of generation %d finished:\n", gen));
5657 print_generation_stats(0);
5661 } while ((gen <= gencgc_oldest_gen_to_gc)
5662 && ((gen < last_gen)
5663 || ((gen <= gencgc_oldest_gen_to_gc)
5665 && (generations[gen].bytes_allocated
5666 > generations[gen].gc_trigger)
5667 && (gen_av_mem_age(gen)
5668 > generations[gen].min_av_mem_age))));
5670 /* Now if gen-1 was raised all generations before gen are empty.
5671 * If it wasn't raised then all generations before gen-1 are empty.
5673 * Now objects within this gen's pages cannot point to younger
5674 * generations unless they are written to. This can be exploited
5675 * by write-protecting the pages of gen; then when younger
5676 * generations are GCed only the pages which have been written
5681 gen_to_wp = gen - 1;
5683 /* There's not much point in WPing pages in generation 0 as it is
5684 * never scavenged (except promoted pages). */
5685 if ((gen_to_wp > 0) && enable_page_protection) {
5686 /* Check that they are all empty. */
5687 for (i = 0; i < gen_to_wp; i++) {
5688 if (generations[i].bytes_allocated)
5689 lose("trying to write-protect gen. %d when gen. %d nonempty",
5692 write_protect_generation_pages(gen_to_wp);
5695 /* Set gc_alloc() back to generation 0. The current regions should
5696 * be flushed after the above GCs. */
5697 gc_assert((boxed_region.free_pointer - boxed_region.start_addr) == 0);
5698 gc_alloc_generation = 0;
5700 update_x86_dynamic_space_free_pointer();
5702 /* This is now done by Lisp SCRUB-CONTROL-STACK in Lisp SUB-GC, so
5703 * we needn't do it here: */
5706 current_region_free_pointer = boxed_region.free_pointer;
5707 current_region_end_addr = boxed_region.end_addr;
5709 SHOW("returning from collect_garbage");
5712 /* This is called by Lisp PURIFY when it is finished. All live objects
5713 * will have been moved to the RO and Static heaps. The dynamic space
5714 * will need a full re-initialization. We don't bother having Lisp
5715 * PURIFY flush the current gc_alloc() region, as the page_tables are
5716 * re-initialized, and every page is zeroed to be sure. */
5722 if (gencgc_verbose > 1)
5723 SHOW("entering gc_free_heap");
5725 for (page = 0; page < NUM_PAGES; page++) {
5726 /* Skip free pages which should already be zero filled. */
5727 if (page_table[page].allocated != FREE_PAGE) {
5728 void *page_start, *addr;
5730 /* Mark the page free. The other slots are assumed invalid
5731 * when it is a FREE_PAGE and bytes_used is 0 and it
5732 * should not be write-protected -- except that the
5733 * generation is used for the current region but it sets
5735 page_table[page].allocated = FREE_PAGE;
5736 page_table[page].bytes_used = 0;
5738 /* Zero the page. */
5739 page_start = (void *)page_address(page);
5741 /* First, remove any write-protection. */
5742 os_protect(page_start, 4096, OS_VM_PROT_ALL);
5743 page_table[page].write_protected = 0;
5745 os_invalidate(page_start,4096);
5746 addr = os_validate(page_start,4096);
5747 if (addr == NULL || addr != page_start) {
5748 lose("gc_free_heap: page moved, 0x%08x ==> 0x%08x",
5752 } else if (gencgc_zero_check_during_free_heap) {
5753 /* Double-check that the page is zero filled. */
5755 gc_assert(page_table[page].allocated == FREE_PAGE);
5756 gc_assert(page_table[page].bytes_used == 0);
5757 page_start = (int *)page_address(page);
5758 for (i=0; i<1024; i++) {
5759 if (page_start[i] != 0) {
5760 lose("free region not zero at %x", page_start + i);
5766 bytes_allocated = 0;
5768 /* Initialize the generations. */
5769 for (page = 0; page < NUM_GENERATIONS; page++) {
5770 generations[page].alloc_start_page = 0;
5771 generations[page].alloc_unboxed_start_page = 0;
5772 generations[page].alloc_large_start_page = 0;
5773 generations[page].alloc_large_unboxed_start_page = 0;
5774 generations[page].bytes_allocated = 0;
5775 generations[page].gc_trigger = 2000000;
5776 generations[page].num_gc = 0;
5777 generations[page].cum_sum_bytes_allocated = 0;
5780 if (gencgc_verbose > 1)
5781 print_generation_stats(0);
5783 /* Initialize gc_alloc(). */
5784 gc_alloc_generation = 0;
5785 boxed_region.first_page = 0;
5786 boxed_region.last_page = -1;
5787 boxed_region.start_addr = page_address(0);
5788 boxed_region.free_pointer = page_address(0);
5789 boxed_region.end_addr = page_address(0);
5790 unboxed_region.first_page = 0;
5791 unboxed_region.last_page = -1;
5792 unboxed_region.start_addr = page_address(0);
5793 unboxed_region.free_pointer = page_address(0);
5794 unboxed_region.end_addr = page_address(0);
5796 #if 0 /* Lisp PURIFY is currently running on the C stack so don't do this. */
5801 SetSymbolValue(ALLOCATION_POINTER, (lispobj)((char *)heap_base));
5803 current_region_free_pointer = boxed_region.free_pointer;
5804 current_region_end_addr = boxed_region.end_addr;
5806 if (verify_after_free_heap) {
5807 /* Check whether purify has left any bad pointers. */
5809 SHOW("checking after free_heap\n");
5821 heap_base = (void*)DYNAMIC_SPACE_START;
5823 /* Initialize each page structure. */
5824 for (i = 0; i < NUM_PAGES; i++) {
5825 /* Initialize all pages as free. */
5826 page_table[i].allocated = FREE_PAGE;
5827 page_table[i].bytes_used = 0;
5829 /* Pages are not write-protected at startup. */
5830 page_table[i].write_protected = 0;
5833 bytes_allocated = 0;
5835 /* Initialize the generations.
5837 * FIXME: very similar to code in gc_free_heap(), should be shared */
5838 for (i = 0; i < NUM_GENERATIONS; i++) {
5839 generations[i].alloc_start_page = 0;
5840 generations[i].alloc_unboxed_start_page = 0;
5841 generations[i].alloc_large_start_page = 0;
5842 generations[i].alloc_large_unboxed_start_page = 0;
5843 generations[i].bytes_allocated = 0;
5844 generations[i].gc_trigger = 2000000;
5845 generations[i].num_gc = 0;
5846 generations[i].cum_sum_bytes_allocated = 0;
5847 /* the tune-able parameters */
5848 generations[i].bytes_consed_between_gc = 2000000;
5849 generations[i].trigger_age = 1;
5850 generations[i].min_av_mem_age = 0.75;
5853 /* Initialize gc_alloc.
5855 * FIXME: identical with code in gc_free_heap(), should be shared */
5856 gc_alloc_generation = 0;
5857 boxed_region.first_page = 0;
5858 boxed_region.last_page = -1;
5859 boxed_region.start_addr = page_address(0);
5860 boxed_region.free_pointer = page_address(0);
5861 boxed_region.end_addr = page_address(0);
5862 unboxed_region.first_page = 0;
5863 unboxed_region.last_page = -1;
5864 unboxed_region.start_addr = page_address(0);
5865 unboxed_region.free_pointer = page_address(0);
5866 unboxed_region.end_addr = page_address(0);
5870 current_region_free_pointer = boxed_region.free_pointer;
5871 current_region_end_addr = boxed_region.end_addr;
5874 /* Pick up the dynamic space from after a core load.
5876 * The ALLOCATION_POINTER points to the end of the dynamic space.
5878 * XX A scan is needed to identify the closest first objects for pages. */
5880 gencgc_pickup_dynamic(void)
5883 int addr = DYNAMIC_SPACE_START;
5884 int alloc_ptr = SymbolValue(ALLOCATION_POINTER);
5886 /* Initialize the first region. */
5888 page_table[page].allocated = BOXED_PAGE;
5889 page_table[page].gen = 0;
5890 page_table[page].bytes_used = 4096;
5891 page_table[page].large_object = 0;
5892 page_table[page].first_object_offset =
5893 (void *)DYNAMIC_SPACE_START - page_address(page);
5896 } while (addr < alloc_ptr);
5898 generations[0].bytes_allocated = 4096*page;
5899 bytes_allocated = 4096*page;
5901 current_region_free_pointer = boxed_region.free_pointer;
5902 current_region_end_addr = boxed_region.end_addr;
5905 /* a counter for how deep we are in alloc(..) calls */
5906 int alloc_entered = 0;
5908 /* alloc(..) is the external interface for memory allocation. It
5909 * allocates to generation 0. It is not called from within the garbage
5910 * collector as it is only external uses that need the check for heap
5911 * size (GC trigger) and to disable the interrupts (interrupts are
5912 * always disabled during a GC).
5914 * The vops that call alloc(..) assume that the returned space is zero-filled.
5915 * (E.g. the most significant word of a 2-word bignum in MOVE-FROM-UNSIGNED.)
5917 * The check for a GC trigger is only performed when the current
5918 * region is full, so in most cases it's not needed. Further MAYBE-GC
5919 * is only called once because Lisp will remember "need to collect
5920 * garbage" and get around to it when it can. */
5924 /* Check for alignment allocation problems. */
5925 gc_assert((((unsigned)current_region_free_pointer & 0x7) == 0)
5926 && ((nbytes & 0x7) == 0));
5928 if (SymbolValue(PSEUDO_ATOMIC_ATOMIC)) {/* if already in a pseudo atomic */
5930 void *new_free_pointer;
5933 if (alloc_entered) {
5934 SHOW("alloc re-entered in already-pseudo-atomic case");
5938 /* Check whether there is room in the current region. */
5939 new_free_pointer = current_region_free_pointer + nbytes;
5941 /* FIXME: Shouldn't we be doing some sort of lock here, to
5942 * keep from getting screwed if an interrupt service routine
5943 * allocates memory between the time we calculate new_free_pointer
5944 * and the time we write it back to current_region_free_pointer?
5945 * Perhaps I just don't understand pseudo-atomics..
5947 * Perhaps I don't. It looks as though what happens is if we
5948 * were interrupted any time during the pseudo-atomic
5949 * interval (which includes now) we discard the allocated
5950 * memory and try again. So, at least we don't return
5951 * a memory area that was allocated out from underneath us
5952 * by code in an ISR.
5953 * Still, that doesn't seem to prevent
5954 * current_region_free_pointer from getting corrupted:
5955 * We read current_region_free_pointer.
5956 * They read current_region_free_pointer.
5957 * They write current_region_free_pointer.
5958 * We write current_region_free_pointer, scribbling over
5959 * whatever they wrote. */
5961 if (new_free_pointer <= boxed_region.end_addr) {
5962 /* If so then allocate from the current region. */
5963 void *new_obj = current_region_free_pointer;
5964 current_region_free_pointer = new_free_pointer;
5966 return((void *)new_obj);
5969 if (auto_gc_trigger && bytes_allocated > auto_gc_trigger) {
5970 /* Double the trigger. */
5971 auto_gc_trigger *= 2;
5973 /* Exit the pseudo-atomic. */
5974 SetSymbolValue(PSEUDO_ATOMIC_ATOMIC, make_fixnum(0));
5975 if (SymbolValue(PSEUDO_ATOMIC_INTERRUPTED) != 0) {
5976 /* Handle any interrupts that occurred during
5978 do_pending_interrupt();
5980 funcall0(SymbolFunction(MAYBE_GC));
5981 /* Re-enter the pseudo-atomic. */
5982 SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED, make_fixnum(0));
5983 SetSymbolValue(PSEUDO_ATOMIC_ATOMIC, make_fixnum(1));
5986 /* Call gc_alloc(). */
5987 boxed_region.free_pointer = current_region_free_pointer;
5989 void *new_obj = gc_alloc(nbytes);
5990 current_region_free_pointer = boxed_region.free_pointer;
5991 current_region_end_addr = boxed_region.end_addr;
5997 void *new_free_pointer;
6000 /* At least wrap this allocation in a pseudo atomic to prevent
6001 * gc_alloc() from being re-entered. */
6002 SetSymbolValue(PSEUDO_ATOMIC_INTERRUPTED, make_fixnum(0));
6003 SetSymbolValue(PSEUDO_ATOMIC_ATOMIC, make_fixnum(1));
6006 SHOW("alloc re-entered in not-already-pseudo-atomic case");
6009 /* Check whether there is room in the current region. */
6010 new_free_pointer = current_region_free_pointer + nbytes;
6012 if (new_free_pointer <= boxed_region.end_addr) {
6013 /* If so then allocate from the current region. */
6014 void *new_obj = current_region_free_pointer;
6015 current_region_free_pointer = new_free_pointer;
6017 SetSymbolValue(PSEUDO_ATOMIC_ATOMIC, make_fixnum(0));
6018 if (SymbolValue(PSEUDO_ATOMIC_INTERRUPTED)) {
6019 /* Handle any interrupts that occurred during
6021 do_pending_interrupt();
6025 return((void *)new_obj);
6028 /* KLUDGE: There's lots of code around here shared with the
6029 * the other branch. Is there some way to factor out the
6030 * duplicate code? -- WHN 19991129 */
6031 if (auto_gc_trigger && bytes_allocated > auto_gc_trigger) {
6032 /* Double the trigger. */
6033 auto_gc_trigger *= 2;
6035 /* Exit the pseudo atomic. */
6036 SetSymbolValue(PSEUDO_ATOMIC_ATOMIC, make_fixnum(0));
6037 if (SymbolValue(PSEUDO_ATOMIC_INTERRUPTED) != 0) {
6038 /* Handle any interrupts that occurred during
6040 do_pending_interrupt();
6042 funcall0(SymbolFunction(MAYBE_GC));
6046 /* Else call gc_alloc(). */
6047 boxed_region.free_pointer = current_region_free_pointer;
6048 result = gc_alloc(nbytes);
6049 current_region_free_pointer = boxed_region.free_pointer;
6050 current_region_end_addr = boxed_region.end_addr;
6053 SetSymbolValue(PSEUDO_ATOMIC_ATOMIC, make_fixnum(0));
6054 if (SymbolValue(PSEUDO_ATOMIC_INTERRUPTED) != 0) {
6055 /* Handle any interrupts that occurred during gc_alloc(..). */
6056 do_pending_interrupt();
6065 * noise to manipulate the gc trigger stuff
6069 set_auto_gc_trigger(os_vm_size_t dynamic_usage)
6071 auto_gc_trigger += dynamic_usage;
6075 clear_auto_gc_trigger(void)
6077 auto_gc_trigger = 0;
6080 /* Find the code object for the given pc, or return NULL on failure.
6082 * FIXME: PC shouldn't be lispobj*, should it? Maybe void*? */
6084 component_ptr_from_pc(lispobj *pc)
6086 lispobj *object = NULL;
6088 if ( (object = search_read_only_space(pc)) )
6090 else if ( (object = search_static_space(pc)) )
6093 object = search_dynamic_space(pc);
6095 if (object) /* if we found something */
6096 if (TypeOf(*object) == type_CodeHeader) /* if it's a code object */
6103 * shared support for the OS-dependent signal handlers which
6104 * catch GENCGC-related write-protect violations
6107 void unhandled_sigmemoryfault(void);
6109 /* Depending on which OS we're running under, different signals might
6110 * be raised for a violation of write protection in the heap. This
6111 * function factors out the common generational GC magic which needs
6112 * to invoked in this case, and should be called from whatever signal
6113 * handler is appropriate for the OS we're running under.
6115 * Return true if this signal is a normal generational GC thing that
6116 * we were able to handle, or false if it was abnormal and control
6117 * should fall through to the general SIGSEGV/SIGBUS/whatever logic. */
6119 gencgc_handle_wp_violation(void* fault_addr)
6121 int page_index = find_page_index(fault_addr);
6123 #if defined QSHOW_SIGNALS
6124 FSHOW((stderr, "heap WP violation? fault_addr=%x, page_index=%d\n",
6125 fault_addr, page_index));
6128 /* Check whether the fault is within the dynamic space. */
6129 if (page_index == (-1)) {
6131 /* It can be helpful to be able to put a breakpoint on this
6132 * case to help diagnose low-level problems. */
6133 unhandled_sigmemoryfault();
6135 /* not within the dynamic space -- not our responsibility */
6140 /* The only acceptable reason for an signal like this from the
6141 * heap is that the generational GC write-protected the page. */
6142 if (page_table[page_index].write_protected != 1) {
6143 lose("access failure in heap page not marked as write-protected");
6146 /* Unprotect the page. */
6147 os_protect(page_address(page_index), 4096, OS_VM_PROT_ALL);
6148 page_table[page_index].write_protected = 0;
6149 page_table[page_index].write_protected_cleared = 1;
6151 /* Don't worry, we can handle it. */
6156 /* This is to be called when we catch a SIGSEGV/SIGBUS, determine that
6157 * it's not just a case of the program hitting the write barrier, and
6158 * are about to let Lisp deal with it. It's basically just a
6159 * convenient place to set a gdb breakpoint. */
6161 unhandled_sigmemoryfault()