diff options
Diffstat (limited to 'jam-files/engine/boehm_gc/alloc.c')
-rw-r--r-- | jam-files/engine/boehm_gc/alloc.c | 1023 |
1 files changed, 1023 insertions, 0 deletions
diff --git a/jam-files/engine/boehm_gc/alloc.c b/jam-files/engine/boehm_gc/alloc.c new file mode 100644 index 000000000..94a968e0a --- /dev/null +++ b/jam-files/engine/boehm_gc/alloc.c @@ -0,0 +1,1023 @@ +/* + * 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) 1999-2004 Hewlett-Packard Development Company, L.P. + * + * 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 MAXOBJBYTES. + * 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_bytes_found; /* Number of reclaimed bytes */ + /* 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. */ + +int GC_never_stop_func (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 (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) { + if (GC_print_stats) { + GC_log_printf("Abandoning stopped marking after "); + GC_log_printf("%lu msecs", time_diff); + GC_log_printf("(attempt %d)\n", GC_n_attempts); + } + 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_bytes_allocd() +{ +# ifdef THREADS + /* We punt, for now. */ + signed_word stack_size = 10000; +# else + int dummy; + 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 = 2 * GC_composite_in_use + GC_atomic_in_use + + 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 bytes allocated, adjusted for explicit storage */ +/* management, etc.. This number is used in deciding when to trigger */ +/* collections. */ +word GC_adj_bytes_allocd(void) +{ + signed_word result; + signed_word expl_managed = + (signed_word)GC_non_gc_bytes + - (signed_word)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_bytes_allocd + - (signed_word)GC_bytes_freed + + (signed_word)GC_finalizer_bytes_freed + - expl_managed; + if (result > (signed_word)GC_bytes_allocd) { + result = GC_bytes_allocd; + /* probably client bug or unfortunate scheduling */ + } + result += GC_bytes_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. */ + if (result < (signed_word)(GC_bytes_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_bytes_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]; + int i; + + for (i = 0; i < NWORDS; i++) frames[i] = 0; +} + +/* Heap size at which we need a collection to avoid expanding past */ +/* limits used by blacklisting. */ +static word GC_collect_at_heapsize = (word)(-1); + +/* Have we allocated enough to amortize a collection? */ +GC_bool GC_should_collect(void) +{ + return(GC_adj_bytes_allocd() >= min_bytes_allocd() + || GC_heapsize >= GC_collect_at_heapsize); +} + + +void GC_notify_full_gc(void) +{ + if (GC_start_call_back != (void (*) (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(void) +{ + 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) { + if (GC_print_stats) { + GC_log_printf( + "***>Full mark for collection %lu after %ld allocd bytes\n", + (unsigned long)GC_gc_no+1, + (long)GC_bytes_allocd); + } + 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(GC_stop_func stop_func) +{ + CLOCK_TYPE start_time, current_time; + if (GC_dont_gc) return FALSE; + if (GC_incremental && GC_collection_in_progress()) { + if (GC_print_stats) { + GC_log_printf( + "GC_try_to_collect_inner: finishing collection in progress\n"); + } + /* 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(); + if (GC_print_stats) { + GET_TIME(start_time); + GC_log_printf( + "Initiating full world-stop collection %lu after %ld allocd bytes\n", + (unsigned long)GC_gc_no+1, (long)GC_bytes_allocd); + } + 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 (GC_print_stats) { + GET_TIME(current_time); + GC_log_printf("Complete collection took %lu msecs\n", + MS_TIME_DIFF(current_time,start_time)); + } + 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 needs 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(int n) +{ + 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(void) +{ + int result; + DCL_LOCK_STATE; + + LOCK(); + GC_collect_a_little_inner(1); + result = (int)GC_collection_in_progress(); + UNLOCK(); + 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(GC_stop_func stop_func) +{ + unsigned i; + int dummy; + CLOCK_TYPE start_time, current_time; + + if (GC_print_stats) + GET_TIME(start_time); + +# if defined(REGISTER_LIBRARIES_EARLY) + GC_cond_register_dynamic_libraries(); +# endif + STOP_WORLD(); + IF_THREADS(GC_world_stopped = TRUE); + if (GC_print_stats) { + GC_log_printf("--> Marking for collection %lu ", + (unsigned long)GC_gc_no + 1); + GC_log_printf("after %lu allocd bytes\n", + (unsigned long) GC_bytes_allocd); + } +# 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)()) { + if (GC_print_stats) { + GC_log_printf("Abandoned stopped marking after "); + GC_log_printf("%u iterations\n", i); + } + 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++; + if (GC_print_stats) { + GC_log_printf("Collection %lu reclaimed %ld bytes", + (unsigned long)GC_gc_no - 1, + (long)GC_bytes_found); + GC_log_printf(" ---> heapsize = %lu bytes\n", + (unsigned long) GC_heapsize); + /* Printf arguments may be pushed in funny places. Clear the */ + /* space. */ + GC_log_printf(""); + } + + /* Check all debugged objects for consistency */ + if (GC_debugging_started) { + (*GC_check_heap)(); + } + + IF_THREADS(GC_world_stopped = FALSE); + START_WORLD(); + if (GC_print_stats) { + GET_TIME(current_time); + GC_log_printf("World-stopped marking took %lu msecs\n", + MS_TIME_DIFF(current_time,start_time)); + } + return(TRUE); +} + +/* Set all mark bits for the free list whose first entry is q */ +void GC_set_fl_marks(ptr_t q) +{ + ptr_t p; + struct hblk * h, * last_h = 0; + hdr *hhdr; /* gcc "might be uninitialized" warning is bogus. */ + IF_PER_OBJ(size_t sz;) + unsigned bit_no; + + for (p = q; p != 0; p = obj_link(p)){ + h = HBLKPTR(p); + if (h != last_h) { + last_h = h; + hhdr = HDR(h); + IF_PER_OBJ(sz = hhdr->hb_sz;) + } + bit_no = MARK_BIT_NO((ptr_t)p - (ptr_t)h, sz); + if (!mark_bit_from_hdr(hhdr, bit_no)) { + set_mark_bit_from_hdr(hhdr, bit_no); + ++hhdr -> hb_n_marks; + } + } +} + +#ifdef GC_ASSERTIONS +/* Check that all mark bits for the free list whose first entry is q */ +/* are set. */ +void GC_check_fl_marks(ptr_t q) +{ + ptr_t p; + + for (p = q; p != 0; p = obj_link(p)){ + if (!GC_is_marked(p)) { + GC_err_printf("Unmarked object %p on list %p\n", p, q); + ABORT("Unmarked local free list entry."); + } + } +} +#endif + +/* Clear all mark bits for the free list whose first entry is q */ +/* Decrement GC_bytes_found by number of bytes on free list. */ +void GC_clear_fl_marks(ptr_t q) +{ + ptr_t p; + struct hblk * h, * last_h = 0; + hdr *hhdr; + size_t sz; + unsigned bit_no; + + for (p = q; p != 0; p = obj_link(p)){ + h = HBLKPTR(p); + if (h != last_h) { + last_h = h; + hhdr = HDR(h); + sz = hhdr->hb_sz; /* Normally set only once. */ + } + bit_no = MARK_BIT_NO((ptr_t)p - (ptr_t)h, sz); + if (mark_bit_from_hdr(hhdr, bit_no)) { + size_t n_marks = hhdr -> hb_n_marks - 1; + clear_mark_bit_from_hdr(hhdr, bit_no); +# ifdef PARALLEL_MARK + /* Appr. count, don't decrement to zero! */ + if (0 != n_marks) { + hhdr -> hb_n_marks = n_marks; + } +# else + hhdr -> hb_n_marks = n_marks; +# endif + } + GC_bytes_found -= sz; + } +} + +#if defined(GC_ASSERTIONS) && defined(THREADS) && defined(THREAD_LOCAL_ALLOC) +extern void GC_check_tls(void); +#endif + +/* Finish up a collection. Assumes lock is held, signals are disabled, */ +/* but the world is otherwise running. */ +void GC_finish_collection() +{ + CLOCK_TYPE start_time; + CLOCK_TYPE finalize_time; + CLOCK_TYPE done_time; + +# if defined(GC_ASSERTIONS) && defined(THREADS) \ + && defined(THREAD_LOCAL_ALLOC) && !defined(DBG_HDRS_ALL) + /* Check that we marked some of our own data. */ + /* FIXME: Add more checks. */ + GC_check_tls(); +# endif + + if (GC_print_stats) + GET_TIME(start_time); + + GC_bytes_found = 0; +# 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. */ + { + word size; /* current object size */ + unsigned kind; + ptr_t q; + + for (kind = 0; kind < GC_n_kinds; kind++) { + for (size = 1; size <= MAXOBJGRANULES; 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 + + if (GC_print_stats) + GET_TIME(finalize_time); + + if (GC_print_back_height) { +# ifdef MAKE_BACK_GRAPH + GC_traverse_back_graph(); +# else +# ifndef SMALL_CONFIG + GC_err_printf("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_bytes_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. */ + { + word size; /* current object size */ + ptr_t q; /* pointer to current object */ + unsigned kind; + + for (kind = 0; kind < GC_n_kinds; kind++) { + for (size = 1; size <= MAXOBJGRANULES; size++) { + q = GC_obj_kinds[kind].ok_freelist[size]; + if (q != 0) GC_clear_fl_marks(q); + } + } + } + + + if (GC_print_stats == VERBOSE) + GC_log_printf("Bytes recovered before sweep - f.l. count = %ld\n", + (long)GC_bytes_found); + + /* Reconstruct free lists to contain everything not marked */ + GC_start_reclaim(FALSE); + if (GC_print_stats) { + GC_log_printf("Heap contains %lu pointer-containing " + "+ %lu pointer-free reachable bytes\n", + (unsigned long)GC_composite_in_use, + (unsigned long)GC_atomic_in_use); + } + if (GC_is_full_gc) { + GC_used_heap_size_after_full = USED_HEAP_SIZE; + GC_need_full_gc = FALSE; + } else { + GC_need_full_gc = + USED_HEAP_SIZE - GC_used_heap_size_after_full + > min_bytes_allocd(); + } + + if (GC_print_stats == VERBOSE) { + GC_log_printf( + "Immediately reclaimed %ld bytes in heap of size %lu bytes", + (long)GC_bytes_found, + (unsigned long)GC_heapsize); +# ifdef USE_MUNMAP + GC_log_printf("(%lu unmapped)", (unsigned long)GC_unmapped_bytes); +# endif + GC_log_printf("\n"); + } + + /* Reset or increment counters for next cycle */ + GC_n_attempts = 0; + GC_is_full_gc = FALSE; + GC_bytes_allocd_before_gc += GC_bytes_allocd; + GC_non_gc_bytes_at_gc = GC_non_gc_bytes; + GC_bytes_allocd = 0; + GC_bytes_freed = 0; + GC_finalizer_bytes_freed = 0; + +# ifdef USE_MUNMAP + GC_unmap_old(); +# endif + if (GC_print_stats) { + GET_TIME(done_time); + GC_log_printf("Finalize + initiate sweep took %lu + %lu msecs\n", + MS_TIME_DIFF(finalize_time,start_time), + MS_TIME_DIFF(done_time,finalize_time)); + } +} + +/* Externally callable routine to invoke full, stop-world collection */ +int GC_try_to_collect(GC_stop_func stop_func) +{ + int result; + DCL_LOCK_STATE; + + if (!GC_is_initialized) GC_init(); + if (GC_debugging_started) GC_print_all_smashed(); + GC_INVOKE_FINALIZERS(); + 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(); + if(result) { + if (GC_debugging_started) GC_print_all_smashed(); + GC_INVOKE_FINALIZERS(); + } + return(result); +} + +void GC_gcollect(void) +{ + (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(struct hblk *p, size_t bytes) +{ + 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++; + phdr -> hb_sz = bytes; + 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 = (void *)((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 = (void *)((ptr_t)p + bytes); + } +} + +# if !defined(NO_DEBUGGING) +void GC_print_heap_sects(void) +{ + unsigned i; + + GC_printf("Total heap size: %lu\n", (unsigned long) GC_heapsize); + for (i = 0; i < GC_n_heap_sects; i++) { + ptr_t start = GC_heap_sects[i].hs_start; + size_t len = GC_heap_sects[i].hs_bytes; + struct hblk *h; + unsigned nbl = 0; + + GC_printf("Section %d from %p to %p ", i, + start, start + len); + for (h = (struct hblk *)start; h < (struct hblk *)(start + len); h++) { + if (GC_is_black_listed(h, HBLKSIZE)) nbl++; + } + GC_printf("%lu/%lu blacklisted\n", (unsigned long)nbl, + (unsigned long)(len/HBLKSIZE)); + } +} +# endif + +void * GC_least_plausible_heap_addr = (void *)ONES; +void * GC_greatest_plausible_heap_addr = 0; + +static INLINE ptr_t GC_max(ptr_t x, ptr_t y) +{ + return(x > y? x : y); +} + +static INLINE ptr_t GC_min(ptr_t x, ptr_t y) +{ + return(x < y? x : y); +} + +void GC_set_max_heap_size(GC_word n) +{ + 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(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 ) { + if (GC_print_stats) { + GC_log_printf("Failed to expand heap by %ld bytes\n", + (unsigned long)bytes); + } + return(FALSE); + } + if (GC_print_stats) { + GC_log_printf("Increasing heap size by %lu after %lu allocated bytes\n", + (unsigned long)bytes, + (unsigned long)GC_bytes_allocd); + } + expansion_slop = min_bytes_allocd() + 4*MAXHINCR*HBLKSIZE; + 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 = + (void *)GC_max((ptr_t)GC_greatest_plausible_heap_addr, + (ptr_t)space + bytes + expansion_slop); + } else { + /* Heap is growing down */ + GC_least_plausible_heap_addr = + (void *)GC_min((ptr_t)GC_least_plausible_heap_addr, + (ptr_t)space - expansion_slop); + } +# if defined(LARGE_CONFIG) + if (((ptr_t)GC_greatest_plausible_heap_addr <= (ptr_t)space + bytes + || (ptr_t)GC_least_plausible_heap_addr >= (ptr_t)space) + && GC_heapsize > 0) { + /* GC_add_to_heap will fix this, but ... */ + WARN("Too close to address space limit: blacklisting ineffective\n", 0); + } +# endif + GC_prev_heap_addr = GC_last_heap_addr; + GC_last_heap_addr = (ptr_t)space; + GC_add_to_heap(space, bytes); + /* Force GC before we are likely to allocate past expansion_slop */ + GC_collect_at_heapsize = + GC_heapsize + expansion_slop - 2*MAXHINCR*HBLKSIZE; +# if defined(LARGE_CONFIG) + if (GC_collect_at_heapsize < GC_heapsize /* wrapped */) + GC_collect_at_heapsize = (word)(-1); +# endif + return(TRUE); +} + +/* Really returns a bool, but it's externally visible, so that's clumsy. */ +/* Arguments is in bytes. */ +int GC_expand_hp(size_t bytes) +{ + int result; + DCL_LOCK_STATE; + + LOCK(); + if (!GC_is_initialized) GC_init_inner(); + result = (int)GC_expand_hp_inner(divHBLKSZ((word)bytes)); + if (result) GC_requested_heapsize += bytes; + UNLOCK(); + return(result); +} + +unsigned GC_fail_count = 0; + /* How many consecutive GC/expansion failures? */ + /* Reset by GC_allochblk. */ + +GC_bool GC_collect_or_expand(word needed_blocks, GC_bool ignore_off_page) +{ + if (!GC_incremental && !GC_dont_gc && + ((GC_dont_expand && GC_bytes_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; + + /* Get the minimum required to make it likely that we */ + /* can satisfy the current request in the presence of black- */ + /* listing. This will probably be more than MAXHINCR. */ + 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 { + if (GC_fail_count && GC_print_stats) { + GC_printf("Memory available again ...\n"); + } + } + } + return(TRUE); +} + +/* + * Make sure the object free list for size gran (in granules) 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(size_t gran, int kind) +{ + void ** flh = &(GC_obj_kinds[kind].ok_freelist[gran]); + GC_bool tried_minor = FALSE; + + if (gran == 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(gran, kind); + EXIT_GC(); + if (*flh == 0) { + GC_new_hblk(gran, 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); +} |