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[Emacs-diffs] Changes to emacs/gc/alloc.c [Boehm-versions]
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From: |
Dave Love |
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Subject: |
[Emacs-diffs] Changes to emacs/gc/alloc.c [Boehm-versions] |
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Date: |
Mon, 16 Jun 2003 11:19:54 -0400 |
Index: emacs/gc/alloc.c
diff -c /dev/null emacs/gc/alloc.c:1.2.2.1.2.1
*** /dev/null Mon Jun 16 11:19:54 2003
--- emacs/gc/alloc.c Mon Jun 16 11:19:52 2003
***************
*** 0 ****
--- 1,1068 ----
+ /*
+ * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
+ * Copyright (c) 1991-1996 by Xerox Corporation. All rights reserved.
+ * Copyright (c) 1998 by Silicon Graphics. All rights reserved.
+ * Copyright (c) 1999 by Hewlett-Packard Company. All rights reserved.
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ *
+ */
+
+
+ # include "private/gc_priv.h"
+
+ # include <stdio.h>
+ # if !defined(MACOS) && !defined(MSWINCE)
+ # include <signal.h>
+ # include <sys/types.h>
+ # endif
+
+ /*
+ * Separate free lists are maintained for different sized objects
+ * up to MAXOBJSZ.
+ * The call GC_allocobj(i,k) ensures that the freelist for
+ * kind k objects of size i points to a non-empty
+ * free list. It returns a pointer to the first entry on the free list.
+ * In a single-threaded world, GC_allocobj may be called to allocate
+ * an object of (small) size i as follows:
+ *
+ * opp = &(GC_objfreelist[i]);
+ * if (*opp == 0) GC_allocobj(i, NORMAL);
+ * ptr = *opp;
+ * *opp = obj_link(ptr);
+ *
+ * Note that this is very fast if the free list is non-empty; it should
+ * only involve the execution of 4 or 5 simple instructions.
+ * All composite objects on freelists are cleared, except for
+ * their first word.
+ */
+
+ /*
+ * The allocator uses GC_allochblk to allocate large chunks of objects.
+ * These chunks all start on addresses which are multiples of
+ * HBLKSZ. Each allocated chunk has an associated header,
+ * which can be located quickly based on the address of the chunk.
+ * (See headers.c for details.)
+ * This makes it possible to check quickly whether an
+ * arbitrary address corresponds to an object administered by the
+ * allocator.
+ */
+
+ word GC_non_gc_bytes = 0; /* Number of bytes not intended to be collected */
+
+ word GC_gc_no = 0;
+
+ #ifndef SMALL_CONFIG
+ int GC_incremental = 0; /* By default, stop the world. */
+ #endif
+
+ int GC_parallel = FALSE; /* By default, parallel GC is off. */
+
+ int GC_full_freq = 19; /* Every 20th collection is a full */
+ /* collection, whether we need it */
+ /* or not. */
+
+ GC_bool GC_need_full_gc = FALSE;
+ /* Need full GC do to heap growth. */
+
+ #ifdef THREADS
+ GC_bool GC_world_stopped = FALSE;
+ # define IF_THREADS(x) x
+ #else
+ # define IF_THREADS(x)
+ #endif
+
+ word GC_used_heap_size_after_full = 0;
+
+ char * GC_copyright[] =
+ {"Copyright 1988,1989 Hans-J. Boehm and Alan J. Demers ",
+ "Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved. ",
+ "Copyright (c) 1996-1998 by Silicon Graphics. All rights reserved. ",
+ "Copyright (c) 1999-2001 by Hewlett-Packard Company. All rights reserved. ",
+ "THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY",
+ " EXPRESSED OR IMPLIED. ANY USE IS AT YOUR OWN RISK.",
+ "See source code for details." };
+
+ # include "version.h"
+
+ /* some more variables */
+
+ extern signed_word GC_mem_found; /* Number of reclaimed longwords */
+ /* after garbage collection */
+
+ GC_bool GC_dont_expand = 0;
+
+ word GC_free_space_divisor = 3;
+
+ extern GC_bool GC_collection_in_progress();
+ /* Collection is in progress, or was abandoned. */
+
+ extern GC_bool GC_print_back_height;
+
+ int GC_never_stop_func GC_PROTO((void)) { return(0); }
+
+ unsigned long GC_time_limit = TIME_LIMIT;
+
+ CLOCK_TYPE GC_start_time; /* Time at which we stopped world. */
+ /* used only in GC_timeout_stop_func. */
+
+ int GC_n_attempts = 0; /* Number of attempts at finishing
*/
+ /* collection within GC_time_limit. */
+
+ #if defined(SMALL_CONFIG) || defined(NO_CLOCK)
+ # define GC_timeout_stop_func GC_never_stop_func
+ #else
+ int GC_timeout_stop_func GC_PROTO((void))
+ {
+ CLOCK_TYPE current_time;
+ static unsigned count = 0;
+ unsigned long time_diff;
+
+ if ((count++ & 3) != 0) return(0);
+ GET_TIME(current_time);
+ time_diff = MS_TIME_DIFF(current_time,GC_start_time);
+ if (time_diff >= GC_time_limit) {
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GC_printf0("Abandoning stopped marking after ");
+ GC_printf1("%lu msecs", (unsigned long)time_diff);
+ GC_printf1("(attempt %d)\n", (unsigned long) GC_n_attempts);
+ }
+ # endif
+ return(1);
+ }
+ return(0);
+ }
+ #endif /* !SMALL_CONFIG */
+
+ /* Return the minimum number of words that must be allocated between */
+ /* collections to amortize the collection cost.
*/
+ static word min_words_allocd()
+ {
+ # ifdef THREADS
+ /* We punt, for now. */
+ register signed_word stack_size = 10000;
+ # else
+ int dummy;
+ register signed_word stack_size = (ptr_t)(&dummy) - GC_stackbottom;
+ # endif
+ word total_root_size; /* includes double stack size, */
+ /* since the stack is expensive */
+ /* to scan. */
+ word scan_size; /* Estimate of memory to be scanned */
+ /* during normal GC. */
+
+ if (stack_size < 0) stack_size = -stack_size;
+ total_root_size = 2 * stack_size + GC_root_size;
+ scan_size = BYTES_TO_WORDS(GC_heapsize - GC_large_free_bytes
+ + (GC_large_free_bytes >> 2)
+ /* use a bit more of large empty heap */
+ + total_root_size);
+ if (TRUE_INCREMENTAL) {
+ return scan_size / (2 * GC_free_space_divisor);
+ } else {
+ return scan_size / GC_free_space_divisor;
+ }
+ }
+
+ /* Return the number of words allocated, adjusted for explicit storage
*/
+ /* management, etc.. This number is used in deciding when to trigger */
+ /* collections.
*/
+ word GC_adj_words_allocd()
+ {
+ register signed_word result;
+ register signed_word expl_managed =
+ BYTES_TO_WORDS((long)GC_non_gc_bytes
+ - (long)GC_non_gc_bytes_at_gc);
+
+ /* Don't count what was explicitly freed, or newly allocated for */
+ /* explicit management. Note that deallocating an explicitly */
+ /* managed object should not alter result, assuming the client */
+ /* is playing by the rules.
*/
+ result = (signed_word)GC_words_allocd
+ - (signed_word)GC_mem_freed
+ + (signed_word)GC_finalizer_mem_freed - expl_managed;
+ if (result > (signed_word)GC_words_allocd) {
+ result = GC_words_allocd;
+ /* probably client bug or unfortunate scheduling */
+ }
+ result += GC_words_finalized;
+ /* We count objects enqueued for finalization as though they */
+ /* had been reallocated this round. Finalization is user */
+ /* visible progress. And if we don't count this, we have */
+ /* stability problems for programs that finalize all objects. */
+ result += GC_words_wasted;
+ /* This doesn't reflect useful work. But if there is lots of */
+ /* new fragmentation, the same is probably true of the heap, */
+ /* and the collection will be correspondingly cheaper. */
+ if (result < (signed_word)(GC_words_allocd >> 3)) {
+ /* Always count at least 1/8 of the allocations. We don't want */
+ /* to collect too infrequently, since that would inhibit */
+ /* coalescing of free storage blocks. */
+ /* This also makes us partially robust against client bugs. */
+ return(GC_words_allocd >> 3);
+ } else {
+ return(result);
+ }
+ }
+
+
+ /* Clear up a few frames worth of garbage left at the top of the stack.
*/
+ /* This is used to prevent us from accidentally treating garbade left */
+ /* on the stack by other parts of the collector as roots. This */
+ /* differs from the code in misc.c, which actually tries to keep the */
+ /* stack clear of long-lived, client-generated garbage.
*/
+ void GC_clear_a_few_frames()
+ {
+ # define NWORDS 64
+ word frames[NWORDS];
+ register int i;
+
+ for (i = 0; i < NWORDS; i++) frames[i] = 0;
+ }
+
+ /* Have we allocated enough to amortize a collection? */
+ GC_bool GC_should_collect()
+ {
+ return(GC_adj_words_allocd() >= min_words_allocd());
+ }
+
+
+ void GC_notify_full_gc()
+ {
+ if (GC_start_call_back != (void (*) GC_PROTO((void)))0) {
+ (*GC_start_call_back)();
+ }
+ }
+
+ GC_bool GC_is_full_gc = FALSE;
+
+ /*
+ * Initiate a garbage collection if appropriate.
+ * Choose judiciously
+ * between partial, full, and stop-world collections.
+ * Assumes lock held, signals disabled.
+ */
+ void GC_maybe_gc()
+ {
+ static int n_partial_gcs = 0;
+
+ if (GC_should_collect()) {
+ if (!GC_incremental) {
+ GC_gcollect_inner();
+ n_partial_gcs = 0;
+ return;
+ } else {
+ # ifdef PARALLEL_MARK
+ GC_wait_for_reclaim();
+ # endif
+ if (GC_need_full_gc || n_partial_gcs >= GC_full_freq) {
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GC_printf2(
+ "***>Full mark for collection %lu after %ld allocd bytes\n",
+ (unsigned long) GC_gc_no+1,
+ (long)WORDS_TO_BYTES(GC_words_allocd));
+ }
+ # endif
+ GC_promote_black_lists();
+ (void)GC_reclaim_all((GC_stop_func)0, TRUE);
+ GC_clear_marks();
+ n_partial_gcs = 0;
+ GC_notify_full_gc();
+ GC_is_full_gc = TRUE;
+ } else {
+ n_partial_gcs++;
+ }
+ }
+ /* We try to mark with the world stopped. */
+ /* If we run out of time, this turns into */
+ /* incremental marking. */
+ # ifndef NO_CLOCK
+ if (GC_time_limit != GC_TIME_UNLIMITED) { GET_TIME(GC_start_time); }
+ # endif
+ if (GC_stopped_mark(GC_time_limit == GC_TIME_UNLIMITED?
+ GC_never_stop_func : GC_timeout_stop_func)) {
+ # ifdef SAVE_CALL_CHAIN
+ GC_save_callers(GC_last_stack);
+ # endif
+ GC_finish_collection();
+ } else {
+ if (!GC_is_full_gc) {
+ /* Count this as the first attempt */
+ GC_n_attempts++;
+ }
+ }
+ }
+ }
+
+
+ /*
+ * Stop the world garbage collection. Assumes lock held, signals disabled.
+ * If stop_func is not GC_never_stop_func, then abort if stop_func returns
TRUE.
+ * Return TRUE if we successfully completed the collection.
+ */
+ GC_bool GC_try_to_collect_inner(stop_func)
+ GC_stop_func stop_func;
+ {
+ # ifdef CONDPRINT
+ CLOCK_TYPE start_time, current_time;
+ # endif
+ if (GC_dont_gc) return FALSE;
+ if (GC_incremental && GC_collection_in_progress()) {
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GC_printf0(
+ "GC_try_to_collect_inner: finishing collection in progress\n");
+ }
+ # endif /* CONDPRINT */
+ /* Just finish collection already in progress. */
+ while(GC_collection_in_progress()) {
+ if (stop_func()) return(FALSE);
+ GC_collect_a_little_inner(1);
+ }
+ }
+ if (stop_func == GC_never_stop_func) GC_notify_full_gc();
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ if (GC_print_stats) GET_TIME(start_time);
+ GC_printf2(
+ "Initiating full world-stop collection %lu after %ld allocd bytes\n",
+ (unsigned long) GC_gc_no+1,
+ (long)WORDS_TO_BYTES(GC_words_allocd));
+ }
+ # endif
+ GC_promote_black_lists();
+ /* Make sure all blocks have been reclaimed, so sweep routines */
+ /* don't see cleared mark bits. */
+ /* If we're guaranteed to finish, then this is unnecessary.
*/
+ /* In the find_leak case, we have to finish to guarantee that */
+ /* previously unmarked objects are not reported as leaks. */
+ # ifdef PARALLEL_MARK
+ GC_wait_for_reclaim();
+ # endif
+ if ((GC_find_leak || stop_func != GC_never_stop_func)
+ && !GC_reclaim_all(stop_func, FALSE)) {
+ /* Aborted. So far everything is still consistent. */
+ return(FALSE);
+ }
+ GC_invalidate_mark_state(); /* Flush mark stack. */
+ GC_clear_marks();
+ # ifdef SAVE_CALL_CHAIN
+ GC_save_callers(GC_last_stack);
+ # endif
+ GC_is_full_gc = TRUE;
+ if (!GC_stopped_mark(stop_func)) {
+ if (!GC_incremental) {
+ /* We're partially done and have no way to complete or use */
+ /* current work. Reestablish invariants as cheaply as */
+ /* possible. */
+ GC_invalidate_mark_state();
+ GC_unpromote_black_lists();
+ } /* else we claim the world is already still consistent. We'll
*/
+ /* finish incrementally. */
+ return(FALSE);
+ }
+ GC_finish_collection();
+ # if defined(CONDPRINT)
+ if (GC_print_stats) {
+ GET_TIME(current_time);
+ GC_printf1("Complete collection took %lu msecs\n",
+ MS_TIME_DIFF(current_time,start_time));
+ }
+ # endif
+ return(TRUE);
+ }
+
+
+
+ /*
+ * Perform n units of garbage collection work. A unit is intended to touch
+ * roughly GC_RATE pages. Every once in a while, we do more than that.
+ * This needa to be a fairly large number with our current incremental
+ * GC strategy, since otherwise we allocate too much during GC, and the
+ * cleanup gets expensive.
+ */
+ # define GC_RATE 10
+ # define MAX_PRIOR_ATTEMPTS 1
+ /* Maximum number of prior attempts at world stop marking */
+ /* A value of 1 means that we finish the second time, no matter */
+ /* how long it takes. Doesn't count the initial root scan */
+ /* for a full GC. */
+
+ int GC_deficit = 0; /* The number of extra calls to GC_mark_some */
+ /* that we have made. */
+
+ void GC_collect_a_little_inner(n)
+ int n;
+ {
+ register int i;
+
+ if (GC_dont_gc) return;
+ if (GC_incremental && GC_collection_in_progress()) {
+ for (i = GC_deficit; i < GC_RATE*n; i++) {
+ if (GC_mark_some((ptr_t)0)) {
+ /* Need to finish a collection */
+ # ifdef SAVE_CALL_CHAIN
+ GC_save_callers(GC_last_stack);
+ # endif
+ # ifdef PARALLEL_MARK
+ GC_wait_for_reclaim();
+ # endif
+ if (GC_n_attempts < MAX_PRIOR_ATTEMPTS
+ && GC_time_limit != GC_TIME_UNLIMITED) {
+ GET_TIME(GC_start_time);
+ if (!GC_stopped_mark(GC_timeout_stop_func)) {
+ GC_n_attempts++;
+ break;
+ }
+ } else {
+ (void)GC_stopped_mark(GC_never_stop_func);
+ }
+ GC_finish_collection();
+ break;
+ }
+ }
+ if (GC_deficit > 0) GC_deficit -= GC_RATE*n;
+ if (GC_deficit < 0) GC_deficit = 0;
+ } else {
+ GC_maybe_gc();
+ }
+ }
+
+ int GC_collect_a_little GC_PROTO(())
+ {
+ int result;
+ DCL_LOCK_STATE;
+
+ DISABLE_SIGNALS();
+ LOCK();
+ GC_collect_a_little_inner(1);
+ result = (int)GC_collection_in_progress();
+ UNLOCK();
+ ENABLE_SIGNALS();
+ if (!result && GC_debugging_started) GC_print_all_smashed();
+ return(result);
+ }
+
+ /*
+ * Assumes lock is held, signals are disabled.
+ * We stop the world.
+ * If stop_func() ever returns TRUE, we may fail and return FALSE.
+ * Increment GC_gc_no if we succeed.
+ */
+ GC_bool GC_stopped_mark(stop_func)
+ GC_stop_func stop_func;
+ {
+ register int i;
+ int dummy;
+ # if defined(PRINTTIMES) || defined(CONDPRINT)
+ CLOCK_TYPE start_time, current_time;
+ # endif
+
+ # ifdef PRINTTIMES
+ GET_TIME(start_time);
+ # endif
+ # if defined(CONDPRINT) && !defined(PRINTTIMES)
+ if (GC_print_stats) GET_TIME(start_time);
+ # endif
+ # if defined(REGISTER_LIBRARIES_EARLY)
+ GC_cond_register_dynamic_libraries();
+ # endif
+ STOP_WORLD();
+ IF_THREADS(GC_world_stopped = TRUE);
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GC_printf1("--> Marking for collection %lu ",
+ (unsigned long) GC_gc_no + 1);
+ GC_printf2("after %lu allocd bytes + %lu wasted bytes\n",
+ (unsigned long) WORDS_TO_BYTES(GC_words_allocd),
+ (unsigned long) WORDS_TO_BYTES(GC_words_wasted));
+ }
+ # endif
+ # ifdef MAKE_BACK_GRAPH
+ if (GC_print_back_height) {
+ GC_build_back_graph();
+ }
+ # endif
+
+ /* Mark from all roots. */
+ /* Minimize junk left in my registers and on the stack */
+ GC_clear_a_few_frames();
+ GC_noop(0,0,0,0,0,0);
+ GC_initiate_gc();
+ for(i = 0;;i++) {
+ if ((*stop_func)()) {
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GC_printf0("Abandoned stopped marking after ");
+ GC_printf1("%lu iterations\n",
+ (unsigned long)i);
+ }
+ # endif
+ GC_deficit = i; /* Give the mutator a chance. */
+ IF_THREADS(GC_world_stopped = FALSE);
+ START_WORLD();
+ return(FALSE);
+ }
+ if (GC_mark_some((ptr_t)(&dummy))) break;
+ }
+
+ GC_gc_no++;
+ # ifdef PRINTSTATS
+ GC_printf2("Collection %lu reclaimed %ld bytes",
+ (unsigned long) GC_gc_no - 1,
+ (long)WORDS_TO_BYTES(GC_mem_found));
+ # else
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GC_printf1("Collection %lu finished", (unsigned long) GC_gc_no - 1);
+ }
+ # endif
+ # endif /* !PRINTSTATS */
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GC_printf1(" ---> heapsize = %lu bytes\n",
+ (unsigned long) GC_heapsize);
+ /* Printf arguments may be pushed in funny places. Clear the */
+ /* space. */
+ GC_printf0("");
+ }
+ # endif /* CONDPRINT */
+
+ /* Check all debugged objects for consistency */
+ if (GC_debugging_started) {
+ (*GC_check_heap)();
+ }
+
+ IF_THREADS(GC_world_stopped = FALSE);
+ START_WORLD();
+ # ifdef PRINTTIMES
+ GET_TIME(current_time);
+ GC_printf1("World-stopped marking took %lu msecs\n",
+ MS_TIME_DIFF(current_time,start_time));
+ # else
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GET_TIME(current_time);
+ GC_printf1("World-stopped marking took %lu msecs\n",
+ MS_TIME_DIFF(current_time,start_time));
+ }
+ # endif
+ # endif
+ return(TRUE);
+ }
+
+ /* Set all mark bits for the free list whose first entry is q */
+ #ifdef __STDC__
+ void GC_set_fl_marks(ptr_t q)
+ #else
+ void GC_set_fl_marks(q)
+ ptr_t q;
+ #endif
+ {
+ ptr_t p;
+ struct hblk * h, * last_h = 0;
+ hdr *hhdr;
+ int word_no;
+
+ for (p = q; p != 0; p = obj_link(p)){
+ h = HBLKPTR(p);
+ if (h != last_h) {
+ last_h = h;
+ hhdr = HDR(h);
+ }
+ word_no = (((word *)p) - ((word *)h));
+ set_mark_bit_from_hdr(hhdr, word_no);
+ }
+ }
+
+ /* Clear all mark bits for the free list whose first entry is q */
+ /* Decrement GC_mem_found by number of words on free list. */
+ #ifdef __STDC__
+ void GC_clear_fl_marks(ptr_t q)
+ #else
+ void GC_clear_fl_marks(q)
+ ptr_t q;
+ #endif
+ {
+ ptr_t p;
+ struct hblk * h, * last_h = 0;
+ hdr *hhdr;
+ int word_no;
+
+ for (p = q; p != 0; p = obj_link(p)){
+ h = HBLKPTR(p);
+ if (h != last_h) {
+ last_h = h;
+ hhdr = HDR(h);
+ }
+ word_no = (((word *)p) - ((word *)h));
+ clear_mark_bit_from_hdr(hhdr, word_no);
+ # ifdef GATHERSTATS
+ GC_mem_found -= hhdr -> hb_sz;
+ # endif
+ }
+ }
+
+ /* Finish up a collection. Assumes lock is held, signals are disabled,
*/
+ /* but the world is otherwise running.
*/
+ void GC_finish_collection()
+ {
+ # ifdef PRINTTIMES
+ CLOCK_TYPE start_time;
+ CLOCK_TYPE finalize_time;
+ CLOCK_TYPE done_time;
+
+ GET_TIME(start_time);
+ finalize_time = start_time;
+ # endif
+
+ # ifdef GATHERSTATS
+ GC_mem_found = 0;
+ # endif
+ # if defined(LINUX) && defined(__ELF__) && !defined(SMALL_CONFIG)
+ if (getenv("GC_PRINT_ADDRESS_MAP") != 0) {
+ GC_print_address_map();
+ }
+ # endif
+ COND_DUMP;
+ if (GC_find_leak) {
+ /* Mark all objects on the free list. All objects should be */
+ /* marked when we're done. */
+ {
+ register word size; /* current object size */
+ int kind;
+ ptr_t q;
+
+ for (kind = 0; kind < GC_n_kinds; kind++) {
+ for (size = 1; size <= MAXOBJSZ; size++) {
+ q = GC_obj_kinds[kind].ok_freelist[size];
+ if (q != 0) GC_set_fl_marks(q);
+ }
+ }
+ }
+ GC_start_reclaim(TRUE);
+ /* The above just checks; it doesn't really reclaim anything. */
+ }
+
+ GC_finalize();
+ # ifdef STUBBORN_ALLOC
+ GC_clean_changing_list();
+ # endif
+
+ # ifdef PRINTTIMES
+ GET_TIME(finalize_time);
+ # endif
+
+ if (GC_print_back_height) {
+ # ifdef MAKE_BACK_GRAPH
+ GC_traverse_back_graph();
+ # else
+ # ifndef SMALL_CONFIG
+ GC_err_printf0("Back height not available: "
+ "Rebuild collector with -DMAKE_BACK_GRAPH\n");
+ # endif
+ # endif
+ }
+
+ /* Clear free list mark bits, in case they got accidentally marked */
+ /* (or GC_find_leak is set and they were intentionally marked). */
+ /* Also subtract memory remaining from GC_mem_found count. */
+ /* Note that composite objects on free list are cleared. */
+ /* Thus accidentally marking a free list is not a problem; only */
+ /* objects on the list itself will be marked, and that's fixed here. */
+ {
+ register word size; /* current object size */
+ register ptr_t q; /* pointer to current object */
+ int kind;
+
+ for (kind = 0; kind < GC_n_kinds; kind++) {
+ for (size = 1; size <= MAXOBJSZ; size++) {
+ q = GC_obj_kinds[kind].ok_freelist[size];
+ if (q != 0) GC_clear_fl_marks(q);
+ }
+ }
+ }
+
+
+ # ifdef PRINTSTATS
+ GC_printf1("Bytes recovered before sweep - f.l. count = %ld\n",
+ (long)WORDS_TO_BYTES(GC_mem_found));
+ # endif
+ /* Reconstruct free lists to contain everything not marked */
+ GC_start_reclaim(FALSE);
+ if (GC_is_full_gc) {
+ GC_used_heap_size_after_full = USED_HEAP_SIZE;
+ GC_need_full_gc = FALSE;
+ } else {
+ GC_need_full_gc =
+ BYTES_TO_WORDS(USED_HEAP_SIZE - GC_used_heap_size_after_full)
+ > min_words_allocd();
+ }
+
+ # ifdef PRINTSTATS
+ GC_printf2(
+ "Immediately reclaimed %ld bytes in heap of size %lu bytes",
+ (long)WORDS_TO_BYTES(GC_mem_found),
+ (unsigned long)GC_heapsize);
+ # ifdef USE_MUNMAP
+ GC_printf1("(%lu unmapped)", GC_unmapped_bytes);
+ # endif
+ GC_printf2(
+ "\n%lu (atomic) + %lu (composite) collectable bytes in use\n",
+ (unsigned long)WORDS_TO_BYTES(GC_atomic_in_use),
+ (unsigned long)WORDS_TO_BYTES(GC_composite_in_use));
+ # endif
+
+ GC_n_attempts = 0;
+ GC_is_full_gc = FALSE;
+ /* Reset or increment counters for next cycle */
+ GC_words_allocd_before_gc += GC_words_allocd;
+ GC_non_gc_bytes_at_gc = GC_non_gc_bytes;
+ GC_words_allocd = 0;
+ GC_words_wasted = 0;
+ GC_mem_freed = 0;
+ GC_finalizer_mem_freed = 0;
+
+ # ifdef USE_MUNMAP
+ GC_unmap_old();
+ # endif
+ # ifdef PRINTTIMES
+ GET_TIME(done_time);
+ GC_printf2("Finalize + initiate sweep took %lu + %lu msecs\n",
+ MS_TIME_DIFF(finalize_time,start_time),
+ MS_TIME_DIFF(done_time,finalize_time));
+ # endif
+ }
+
+ /* Externally callable routine to invoke full, stop-world collection */
+ # if defined(__STDC__) || defined(__cplusplus)
+ int GC_try_to_collect(GC_stop_func stop_func)
+ # else
+ int GC_try_to_collect(stop_func)
+ GC_stop_func stop_func;
+ # endif
+ {
+ int result;
+ DCL_LOCK_STATE;
+
+ if (GC_debugging_started) GC_print_all_smashed();
+ GC_INVOKE_FINALIZERS();
+ DISABLE_SIGNALS();
+ LOCK();
+ ENTER_GC();
+ if (!GC_is_initialized) GC_init_inner();
+ /* Minimize junk left in my registers */
+ GC_noop(0,0,0,0,0,0);
+ result = (int)GC_try_to_collect_inner(stop_func);
+ EXIT_GC();
+ UNLOCK();
+ ENABLE_SIGNALS();
+ if(result) {
+ if (GC_debugging_started) GC_print_all_smashed();
+ GC_INVOKE_FINALIZERS();
+ }
+ return(result);
+ }
+
+ void GC_gcollect GC_PROTO(())
+ {
+ (void)GC_try_to_collect(GC_never_stop_func);
+ if (GC_have_errors) GC_print_all_errors();
+ }
+
+ word GC_n_heap_sects = 0; /* Number of sections currently in heap. */
+
+ /*
+ * Use the chunk of memory starting at p of size bytes as part of the heap.
+ * Assumes p is HBLKSIZE aligned, and bytes is a multiple of HBLKSIZE.
+ */
+ void GC_add_to_heap(p, bytes)
+ struct hblk *p;
+ word bytes;
+ {
+ word words;
+ hdr * phdr;
+
+ if (GC_n_heap_sects >= MAX_HEAP_SECTS) {
+ ABORT("Too many heap sections: Increase MAXHINCR or MAX_HEAP_SECTS");
+ }
+ phdr = GC_install_header(p);
+ if (0 == phdr) {
+ /* This is extremely unlikely. Can't add it. This will */
+ /* almost certainly result in a 0 return from the allocator, */
+ /* which is entirely appropriate. */
+ return;
+ }
+ GC_heap_sects[GC_n_heap_sects].hs_start = (ptr_t)p;
+ GC_heap_sects[GC_n_heap_sects].hs_bytes = bytes;
+ GC_n_heap_sects++;
+ words = BYTES_TO_WORDS(bytes);
+ phdr -> hb_sz = words;
+ phdr -> hb_map = (unsigned char *)1; /* A value != GC_invalid_map
*/
+ phdr -> hb_flags = 0;
+ GC_freehblk(p);
+ GC_heapsize += bytes;
+ if ((ptr_t)p <= (ptr_t)GC_least_plausible_heap_addr
+ || GC_least_plausible_heap_addr == 0) {
+ GC_least_plausible_heap_addr = (GC_PTR)((ptr_t)p - sizeof(word));
+ /* Making it a little smaller than necessary prevents */
+ /* us from getting a false hit from the variable */
+ /* itself. There's some unintentional reflection */
+ /* here. */
+ }
+ if ((ptr_t)p + bytes >= (ptr_t)GC_greatest_plausible_heap_addr) {
+ GC_greatest_plausible_heap_addr = (GC_PTR)((ptr_t)p + bytes);
+ }
+ }
+
+ # if !defined(NO_DEBUGGING)
+ void GC_print_heap_sects()
+ {
+ register unsigned i;
+
+ GC_printf1("Total heap size: %lu\n", (unsigned long) GC_heapsize);
+ for (i = 0; i < GC_n_heap_sects; i++) {
+ unsigned long start = (unsigned long) GC_heap_sects[i].hs_start;
+ unsigned long len = (unsigned long) GC_heap_sects[i].hs_bytes;
+ struct hblk *h;
+ unsigned nbl = 0;
+
+ GC_printf3("Section %ld from 0x%lx to 0x%lx ", (unsigned long)i,
+ start, (unsigned long)(start + len));
+ for (h = (struct hblk *)start; h < (struct hblk *)(start + len); h++) {
+ if (GC_is_black_listed(h, HBLKSIZE)) nbl++;
+ }
+ GC_printf2("%lu/%lu blacklisted\n", (unsigned long)nbl,
+ (unsigned long)(len/HBLKSIZE));
+ }
+ }
+ # endif
+
+ GC_PTR GC_least_plausible_heap_addr = (GC_PTR)ONES;
+ GC_PTR GC_greatest_plausible_heap_addr = 0;
+
+ ptr_t GC_max(x,y)
+ ptr_t x, y;
+ {
+ return(x > y? x : y);
+ }
+
+ ptr_t GC_min(x,y)
+ ptr_t x, y;
+ {
+ return(x < y? x : y);
+ }
+
+ # if defined(__STDC__) || defined(__cplusplus)
+ void GC_set_max_heap_size(GC_word n)
+ # else
+ void GC_set_max_heap_size(n)
+ GC_word n;
+ # endif
+ {
+ GC_max_heapsize = n;
+ }
+
+ GC_word GC_max_retries = 0;
+
+ /*
+ * this explicitly increases the size of the heap. It is used
+ * internally, but may also be invoked from GC_expand_hp by the user.
+ * The argument is in units of HBLKSIZE.
+ * Tiny values of n are rounded up.
+ * Returns FALSE on failure.
+ */
+ GC_bool GC_expand_hp_inner(n)
+ word n;
+ {
+ word bytes;
+ struct hblk * space;
+ word expansion_slop; /* Number of bytes by which we expect the */
+ /* heap to expand soon. */
+
+ if (n < MINHINCR) n = MINHINCR;
+ bytes = n * HBLKSIZE;
+ /* Make sure bytes is a multiple of GC_page_size */
+ {
+ word mask = GC_page_size - 1;
+ bytes += mask;
+ bytes &= ~mask;
+ }
+
+ if (GC_max_heapsize != 0 && GC_heapsize + bytes > GC_max_heapsize) {
+ /* Exceeded self-imposed limit */
+ return(FALSE);
+ }
+ space = GET_MEM(bytes);
+ if( space == 0 ) {
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GC_printf1("Failed to expand heap by %ld bytes\n",
+ (unsigned long)bytes);
+ }
+ # endif
+ return(FALSE);
+ }
+ # ifdef CONDPRINT
+ if (GC_print_stats) {
+ GC_printf2("Increasing heap size by %lu after %lu allocated bytes\n",
+ (unsigned long)bytes,
+ (unsigned long)WORDS_TO_BYTES(GC_words_allocd));
+ # ifdef UNDEFINED
+ GC_printf1("Root size = %lu\n", GC_root_size);
+ GC_print_block_list(); GC_print_hblkfreelist();
+ GC_printf0("\n");
+ # endif
+ }
+ # endif
+ expansion_slop = 8 * WORDS_TO_BYTES(min_words_allocd());
+ if (5 * HBLKSIZE * MAXHINCR > expansion_slop) {
+ expansion_slop = 5 * HBLKSIZE * MAXHINCR;
+ }
+ if (GC_last_heap_addr == 0 && !((word)space & SIGNB)
+ || GC_last_heap_addr != 0 && GC_last_heap_addr < (ptr_t)space) {
+ /* Assume the heap is growing up */
+ GC_greatest_plausible_heap_addr =
+ GC_max(GC_greatest_plausible_heap_addr,
+ (ptr_t)space + bytes + expansion_slop);
+ } else {
+ /* Heap is growing down */
+ GC_least_plausible_heap_addr =
+ GC_min(GC_least_plausible_heap_addr,
+ (ptr_t)space - expansion_slop);
+ }
+ GC_prev_heap_addr = GC_last_heap_addr;
+ GC_last_heap_addr = (ptr_t)space;
+ GC_add_to_heap(space, bytes);
+ return(TRUE);
+ }
+
+ /* Really returns a bool, but it's externally visible, so that's clumsy. */
+ /* Arguments is in bytes. */
+ # if defined(__STDC__) || defined(__cplusplus)
+ int GC_expand_hp(size_t bytes)
+ # else
+ int GC_expand_hp(bytes)
+ size_t bytes;
+ # endif
+ {
+ int result;
+ DCL_LOCK_STATE;
+
+ DISABLE_SIGNALS();
+ LOCK();
+ if (!GC_is_initialized) GC_init_inner();
+ result = (int)GC_expand_hp_inner(divHBLKSZ((word)bytes));
+ if (result) GC_requested_heapsize += bytes;
+ UNLOCK();
+ ENABLE_SIGNALS();
+ return(result);
+ }
+
+ unsigned GC_fail_count = 0;
+ /* How many consecutive GC/expansion failures? */
+ /* Reset by GC_allochblk. */
+
+ GC_bool GC_collect_or_expand(needed_blocks, ignore_off_page)
+ word needed_blocks;
+ GC_bool ignore_off_page;
+ {
+ if (!GC_incremental && !GC_dont_gc &&
+ (GC_dont_expand && GC_words_allocd > 0 || GC_should_collect())) {
+ GC_gcollect_inner();
+ } else {
+ word blocks_to_get = GC_heapsize/(HBLKSIZE*GC_free_space_divisor)
+ + needed_blocks;
+
+ if (blocks_to_get > MAXHINCR) {
+ word slop;
+
+ if (ignore_off_page) {
+ slop = 4;
+ } else {
+ slop = 2*divHBLKSZ(BL_LIMIT);
+ if (slop > needed_blocks) slop = needed_blocks;
+ }
+ if (needed_blocks + slop > MAXHINCR) {
+ blocks_to_get = needed_blocks + slop;
+ } else {
+ blocks_to_get = MAXHINCR;
+ }
+ }
+ if (!GC_expand_hp_inner(blocks_to_get)
+ && !GC_expand_hp_inner(needed_blocks)) {
+ if (GC_fail_count++ < GC_max_retries) {
+ WARN("Out of Memory! Trying to continue ...\n", 0);
+ GC_gcollect_inner();
+ } else {
+ # if !defined(AMIGA) || !defined(GC_AMIGA_FASTALLOC)
+ WARN("Out of Memory! Returning NIL!\n", 0);
+ # endif
+ return(FALSE);
+ }
+ } else {
+ # ifdef CONDPRINT
+ if (GC_fail_count && GC_print_stats) {
+ GC_printf0("Memory available again ...\n");
+ }
+ # endif
+ }
+ }
+ return(TRUE);
+ }
+
+ /*
+ * Make sure the object free list for sz is not empty.
+ * Return a pointer to the first object on the free list.
+ * The object MUST BE REMOVED FROM THE FREE LIST BY THE CALLER.
+ * Assumes we hold the allocator lock and signals are disabled.
+ *
+ */
+ ptr_t GC_allocobj(sz, kind)
+ word sz;
+ int kind;
+ {
+ ptr_t * flh = &(GC_obj_kinds[kind].ok_freelist[sz]);
+ GC_bool tried_minor = FALSE;
+
+ if (sz == 0) return(0);
+
+ while (*flh == 0) {
+ ENTER_GC();
+ /* Do our share of marking work */
+ if(TRUE_INCREMENTAL) GC_collect_a_little_inner(1);
+ /* Sweep blocks for objects of this size */
+ GC_continue_reclaim(sz, kind);
+ EXIT_GC();
+ if (*flh == 0) {
+ GC_new_hblk(sz, kind);
+ }
+ if (*flh == 0) {
+ ENTER_GC();
+ if (GC_incremental && GC_time_limit == GC_TIME_UNLIMITED
+ && ! tried_minor ) {
+ GC_collect_a_little_inner(1);
+ tried_minor = TRUE;
+ } else {
+ if (!GC_collect_or_expand((word)1,FALSE)) {
+ EXIT_GC();
+ return(0);
+ }
+ }
+ EXIT_GC();
+ }
+ }
+ /* Successful allocation; reset failure count. */
+ GC_fail_count = 0;
+
+ return(*flh);
+ }
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