DUK_INTERNAL void duk_heap_free_strtab(duk_heap *heap) {
/* Free strings in the stringtable and any allocations needed
* by the stringtable itself.
*/
duk_uint_fast32_t i, j;
duk_strtab_entry *e;
#if defined(DUK_USE_HEAPPTR16)
duk_uint16_t *lst;
duk_uint16_t null16 = heap->heapptr_null16;
#else
duk_hstring **lst;
#endif
duk_hstring *h;
for (i = 0; i < DUK_STRTAB_CHAIN_SIZE; i++) {
e = heap->strtable + i;
if (e->listlen > 0) {
#if defined(DUK_USE_HEAPPTR16)
lst = (duk_uint16_t *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, e->u.strlist16);
#else
lst = e->u.strlist;
#endif
DUK_ASSERT(lst != NULL);
for (j = 0; j < e->listlen; j++) {
#if defined(DUK_USE_HEAPPTR16)
h = DUK_USE_HEAPPTR_DEC16(heap->heap_udata, lst[j]);
lst[j] = null16;
#else
h = lst[j];
lst[j] = NULL;
#endif
/* strings may have inner refs (extdata) in some cases */
if (h != NULL) {
duk_free_hstring_inner(heap, h);
DUK_FREE(heap, h);
}
}
#if defined(DUK_USE_HEAPPTR16)
e->u.strlist16 = null16;
#else
e->u.strlist = NULL;
#endif
DUK_FREE(heap, lst);
} else {
#if defined(DUK_USE_HEAPPTR16)
h = DUK_USE_HEAPPTR_DEC16(heap->heap_udata, e->u.str16);
e->u.str16 = null16;
#else
h = e->u.str;
e->u.str = NULL;
#endif
if (h != NULL) {
duk_free_hstring_inner(heap, h);
DUK_FREE(heap, h);
}
}
e->listlen = 0;
}
}
DUK_LOCAL void duk__sweep_string_chain16(duk_heap *heap, duk_uint16_t *slot, duk_size_t *count_keep, duk_size_t *count_free) {
duk_uint16_t h16 = *slot;
duk_hstring *h;
duk_uint16_t null16 = heap->heapptr_null16;
if (h16 == null16) {
/* nop */
return;
}
h = (duk_hstring *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, h16);
DUK_ASSERT(h != NULL);
if (DUK_HEAPHDR_HAS_REACHABLE((duk_heaphdr *) h)) {
DUK_HEAPHDR_CLEAR_REACHABLE((duk_heaphdr *) h);
(*count_keep)++;
} else {
#if defined(DUK_USE_REFERENCE_COUNTING)
DUK_ASSERT(DUK_HEAPHDR_GET_REFCOUNT((duk_heaphdr *) h) == 0);
#endif
/* deal with weak references first */
duk_heap_strcache_string_remove(heap, (duk_hstring *) h);
*slot = null16;
/* free inner references (these exist e.g. when external
* strings are enabled)
*/
duk_free_hstring_inner(heap, h);
DUK_FREE(heap, h);
(*count_free)++;
}
}
DUK_LOCAL duk_bool_t duk__insert_hstring_chain(duk_heap *heap, duk_hstring *h) {
duk_small_uint_t slotidx;
duk_strtab_entry *e;
duk_uint16_t *lst;
duk_uint16_t *new_lst;
duk_size_t i, n;
duk_uint16_t null16 = heap->heapptr_null16;
duk_uint16_t h16 = DUK_USE_HEAPPTR_ENC16(heap->heap_udata, (void *) h);
DUK_ASSERT(heap != NULL);
DUK_ASSERT(h != NULL);
slotidx = DUK_HSTRING_GET_HASH(h) % DUK_STRTAB_CHAIN_SIZE;
DUK_ASSERT(slotidx < DUK_STRTAB_CHAIN_SIZE);
e = heap->strtable + slotidx;
if (e->listlen == 0) {
if (e->u.str16 == null16) {
e->u.str16 = h16;
} else {
/* Now two entries in the same slot, alloc list */
lst = (duk_uint16_t *) DUK_ALLOC(heap, sizeof(duk_uint16_t) * 2);
if (lst == NULL) {
return 1; /* fail */
}
lst[0] = e->u.str16;
lst[1] = h16;
e->u.strlist16 = DUK_USE_HEAPPTR_ENC16(heap->heap_udata, (void *) lst);
e->listlen = 2;
}
} else {
DUK_ASSERT(e->u.strlist16 != null16);
lst = (duk_uint16_t *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, e->u.strlist16);
DUK_ASSERT(lst != NULL);
for (i = 0, n = e->listlen; i < n; i++) {
if (lst[i] == null16) {
lst[i] = h16;
return 0;
}
}
if (e->listlen + 1 == 0) {
/* Overflow, relevant mainly when listlen is 16 bits. */
return 1; /* fail */
}
new_lst = (duk_uint16_t *) DUK_REALLOC(heap, lst, sizeof(duk_uint16_t) * (e->listlen + 1));
if (new_lst == NULL) {
return 1; /* fail */
}
new_lst[e->listlen++] = h16;
e->u.strlist16 = DUK_USE_HEAPPTR_ENC16(heap->heap_udata, (void *) new_lst);
}
return 0;
}
DUK_LOCAL duk_hstring *duk__find_matching_string_chain(duk_heap *heap, const duk_uint8_t *str, duk_uint32_t blen, duk_uint32_t strhash) {
duk_small_uint_t slotidx;
duk_strtab_entry *e;
duk_uint16_t *lst;
duk_size_t i, n;
duk_uint16_t null16 = heap->heapptr_null16;
DUK_ASSERT(heap != NULL);
slotidx = strhash % DUK_STRTAB_CHAIN_SIZE;
DUK_ASSERT(slotidx < DUK_STRTAB_CHAIN_SIZE);
e = heap->strtable + slotidx;
if (e->listlen == 0) {
if (e->u.str16 != null16) {
duk_hstring *h = (duk_hstring *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, e->u.str16);
DUK_ASSERT(h != NULL);
if (DUK_HSTRING_GET_BYTELEN(h) == blen &&
DUK_MEMCMP((const void *) str, (const void *) DUK_HSTRING_GET_DATA(h), (size_t) blen) == 0) {
return h;
}
}
} else {
DUK_ASSERT(e->u.strlist16 != null16);
lst = (duk_uint16_t *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, e->u.strlist16);
DUK_ASSERT(lst != NULL);
for (i = 0, n = e->listlen; i < n; i++) {
if (lst[i] != null16) {
duk_hstring *h = (duk_hstring *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, lst[i]);
DUK_ASSERT(h != NULL);
if (DUK_HSTRING_GET_BYTELEN(h) == blen &&
DUK_MEMCMP((const void *) str, (const void *) DUK_HSTRING_GET_DATA(h), (size_t) blen) == 0) {
return h;
}
}
}
}
return NULL;
}
DUK_LOCAL void duk__sweep_stringtable_chain(duk_heap *heap, duk_size_t *out_count_keep) {
duk_strtab_entry *e;
duk_uint_fast32_t i;
duk_size_t count_free = 0;
duk_size_t count_keep = 0;
duk_size_t j, n;
#if defined(DUK_USE_HEAPPTR16)
duk_uint16_t *lst;
#else
duk_hstring **lst;
#endif
DUK_DD(DUK_DDPRINT("duk__sweep_stringtable: %p", (void *) heap));
/* Non-zero refcounts should not happen for unreachable strings,
* because we refcount finalize all unreachable objects which
* should have decreased unreachable string refcounts to zero
* (even for cycles).
*/
for (i = 0; i < DUK_STRTAB_CHAIN_SIZE; i++) {
e = heap->strtable + i;
if (e->listlen == 0) {
#if defined(DUK_USE_HEAPPTR16)
duk__sweep_string_chain16(heap, &e->u.str16, &count_keep, &count_free);
#else
duk__sweep_string_chain(heap, &e->u.str, &count_keep, &count_free);
#endif
} else {
#if defined(DUK_USE_HEAPPTR16)
lst = (duk_uint16_t *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, e->u.strlist16);
#else
lst = e->u.strlist;
#endif
for (j = 0, n = e->listlen; j < n; j++) {
#if defined(DUK_USE_HEAPPTR16)
duk__sweep_string_chain16(heap, lst + j, &count_keep, &count_free);
#else
duk__sweep_string_chain(heap, lst + j, &count_keep, &count_free);
#endif
}
}
}
DUK_D(DUK_DPRINT("mark-and-sweep sweep stringtable: %ld freed, %ld kept",
(long) count_free, (long) count_keep));
*out_count_keep = count_keep;
}
DUK_INTERNAL void duk_heap_dump_strtab(duk_heap *heap) {
duk_uint32_t i;
duk_hstring *h;
DUK_ASSERT(heap != NULL);
#if defined(DUK_USE_HEAPPTR16)
DUK_ASSERT(heap->strtable16 != NULL);
#else
DUK_ASSERT(heap->strtable != NULL);
#endif
for (i = 0; i < heap->st_size; i++) {
#if defined(DUK_USE_HEAPPTR16)
h = (duk_hstring *) DUK_USE_HEAPPTR_DEC16(heap->strtable16[i]);
#else
h = heap->strtable[i];
#endif
DUK_DD(DUK_DDPRINT("[%03d] -> %p", (int) i, (void *) h));
}
}
DUK_LOCAL void duk__remove_matching_hstring_chain(duk_heap *heap, duk_hstring *h) {
duk_small_uint_t slotidx;
duk_strtab_entry *e;
duk_uint16_t *lst;
duk_size_t i, n;
duk_uint16_t h16;
duk_uint16_t null16 = heap->heapptr_null16;
DUK_ASSERT(heap != NULL);
DUK_ASSERT(h != NULL);
slotidx = DUK_HSTRING_GET_HASH(h) % DUK_STRTAB_CHAIN_SIZE;
DUK_ASSERT(slotidx < DUK_STRTAB_CHAIN_SIZE);
DUK_ASSERT(h != NULL);
h16 = DUK_USE_HEAPPTR_ENC16(heap->heap_udata, (void *) h);
e = heap->strtable + slotidx;
if (e->listlen == 0) {
if (e->u.str16 == h16) {
e->u.str16 = null16;
return;
}
} else {
DUK_ASSERT(e->u.strlist16 != null16);
lst = (duk_uint16_t *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, e->u.strlist16);
DUK_ASSERT(lst != NULL);
for (i = 0, n = e->listlen; i < n; i++) {
if (lst[i] == h16) {
lst[i] = null16;
return;
}
}
}
DUK_D(DUK_DPRINT("failed to find string that should be in stringtable"));
DUK_UNREACHABLE();
return;
}
DUK_INTERNAL void duk_heap_free_strtab(duk_heap *heap) {
duk_uint_fast32_t i;
duk_hstring *h;
#if defined(DUK_USE_HEAPPTR16)
if (heap->strtable16) {
#else
if (heap->strtable) {
#endif
for (i = 0; i < (duk_uint_fast32_t) heap->st_size; i++) {
#if defined(DUK_USE_HEAPPTR16)
h = (duk_hstring *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, heap->strtable16[i]);
#else
h = heap->strtable[i];
#endif
if (h == NULL || h == DUK_STRTAB_DELETED_MARKER(heap)) {
continue;
}
DUK_ASSERT(h != NULL);
/* strings may have inner refs (extdata) in some cases */
duk_free_hstring_inner(heap, h);
DUK_FREE(heap, h);
#if 0 /* not strictly necessary */
heap->strtable[i] = NULL;
#endif
}
#if defined(DUK_USE_HEAPPTR16)
DUK_FREE(heap, heap->strtable16);
#else
DUK_FREE(heap, heap->strtable);
#endif
#if 0 /* not strictly necessary */
heap->strtable = NULL;
#endif
}
}
DUK_LOCAL void duk__remove_matching_hstring_probe(duk_heap *heap, duk_uint16_t *entries16, duk_uint32_t size, duk_hstring *h) {
#else
DUK_LOCAL void duk__remove_matching_hstring_probe(duk_heap *heap, duk_hstring **entries, duk_uint32_t size, duk_hstring *h) {
#endif
duk_uint32_t i;
duk_uint32_t step;
duk_uint32_t hash;
#if defined(DUK_USE_HEAPPTR16)
duk_uint16_t null16 = heap->heapptr_null16;
duk_uint16_t h16 = DUK_USE_HEAPPTR_ENC16(heap->heap_udata, (void *) h);
#endif
DUK_ASSERT(size > 0);
hash = DUK_HSTRING_GET_HASH(h);
i = DUK__HASH_INITIAL(hash, size);
step = DUK__HASH_PROBE_STEP(hash);
for (;;) {
#if defined(DUK_USE_HEAPPTR16)
duk_uint16_t e16 = entries16[i];
#else
duk_hstring *e = entries[i];
#endif
#if defined(DUK_USE_HEAPPTR16)
if (e16 == null16) {
#else
if (!e) {
#endif
DUK_UNREACHABLE();
break;
}
#if defined(DUK_USE_HEAPPTR16)
if (e16 == h16) {
#else
if (e == h) {
#endif
/* st_used remains the same, DELETED is counted as used */
DUK_DDD(DUK_DDDPRINT("free matching hit: %ld", (long) i));
#if defined(DUK_USE_HEAPPTR16)
entries16[i] = heap->heapptr_deleted16;
#else
entries[i] = DUK__DELETED_MARKER(heap);
#endif
break;
}
DUK_DDD(DUK_DDDPRINT("free matching miss: %ld", (long) i));
i = (i + step) % size;
/* looping should never happen */
DUK_ASSERT(i != DUK__HASH_INITIAL(hash, size));
}
}
DUK_LOCAL duk_bool_t duk__resize_strtab_raw_probe(duk_heap *heap, duk_uint32_t new_size) {
#ifdef DUK_USE_MARK_AND_SWEEP
duk_small_uint_t prev_mark_and_sweep_base_flags;
#endif
#ifdef DUK_USE_DEBUG
duk_uint32_t old_used = heap->st_used;
#endif
duk_uint32_t old_size = heap->st_size;
#if defined(DUK_USE_HEAPPTR16)
duk_uint16_t *old_entries = heap->strtable16;
duk_uint16_t *new_entries = NULL;
#else
duk_hstring **old_entries = heap->strtable;
duk_hstring **new_entries = NULL;
#endif
duk_uint32_t new_used = 0;
duk_uint32_t i;
#ifdef DUK_USE_DEBUG
DUK_UNREF(old_used); /* unused with some debug level combinations */
#endif
#ifdef DUK_USE_DDDPRINT
DUK_DDD(DUK_DDDPRINT("attempt to resize stringtable: %ld entries, %ld bytes, %ld used, %ld%% load -> %ld entries, %ld bytes, %ld used, %ld%% load",
(long) old_size, (long) (sizeof(duk_hstring *) * old_size), (long) old_used,
(long) (((double) old_used) / ((double) old_size) * 100.0),
(long) new_size, (long) (sizeof(duk_hstring *) * new_size), (long) duk__count_used_probe(heap),
(long) (((double) duk__count_used_probe(heap)) / ((double) new_size) * 100.0)));
#endif
DUK_ASSERT(new_size > (duk_uint32_t) duk__count_used_probe(heap)); /* required for rehash to succeed, equality not that useful */
DUK_ASSERT(old_entries);
#ifdef DUK_USE_MARK_AND_SWEEP
DUK_ASSERT((heap->mark_and_sweep_base_flags & DUK_MS_FLAG_NO_STRINGTABLE_RESIZE) == 0);
#endif
/*
* The attempt to allocate may cause a GC. Such a GC must not attempt to resize
* the stringtable (though it can be swept); finalizer execution and object
* compaction must also be postponed to avoid the pressure to add strings to the
* string table.
*/
#ifdef DUK_USE_MARK_AND_SWEEP
prev_mark_and_sweep_base_flags = heap->mark_and_sweep_base_flags;
heap->mark_and_sweep_base_flags |= \
DUK_MS_FLAG_NO_STRINGTABLE_RESIZE | /* avoid recursive call here */
DUK_MS_FLAG_NO_FINALIZERS | /* avoid pressure to add/remove strings */
DUK_MS_FLAG_NO_OBJECT_COMPACTION; /* avoid array abandoning which interns strings */
#endif
#if defined(DUK_USE_HEAPPTR16)
new_entries = (duk_uint16_t *) DUK_ALLOC(heap, sizeof(duk_uint16_t) * new_size);
#else
new_entries = (duk_hstring **) DUK_ALLOC(heap, sizeof(duk_hstring *) * new_size);
#endif
#ifdef DUK_USE_MARK_AND_SWEEP
heap->mark_and_sweep_base_flags = prev_mark_and_sweep_base_flags;
#endif
if (!new_entries) {
goto resize_error;
}
#ifdef DUK_USE_EXPLICIT_NULL_INIT
for (i = 0; i < new_size; i++) {
#if defined(DUK_USE_HEAPPTR16)
new_entries[i] = heap->heapptr_null16;
#else
new_entries[i] = NULL;
#endif
}
#else
#if defined(DUK_USE_HEAPPTR16)
/* Relies on NULL encoding to zero. */
DUK_MEMZERO(new_entries, sizeof(duk_uint16_t) * new_size);
#else
DUK_MEMZERO(new_entries, sizeof(duk_hstring *) * new_size);
#endif
#endif
/* Because new_size > duk__count_used_probe(heap), guaranteed to work */
for (i = 0; i < old_size; i++) {
duk_hstring *e;
#if defined(DUK_USE_HEAPPTR16)
e = (duk_hstring *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, old_entries[i]);
#else
e = old_entries[i];
#endif
if (e == NULL || e == DUK__DELETED_MARKER(heap)) {
continue;
}
/* checking for DUK__DELETED_MARKER is not necessary here, but helper does it now */
duk__insert_hstring_probe(heap, new_entries, new_size, &new_used, e);
}
#ifdef DUK_USE_DDPRINT
DUK_DD(DUK_DDPRINT("resized stringtable: %ld entries, %ld bytes, %ld used, %ld%% load -> %ld entries, %ld bytes, %ld used, %ld%% load",
(long) old_size, (long) (sizeof(duk_hstring *) * old_size), (long) old_used,
(long) (((double) old_used) / ((double) old_size) * 100.0),
(long) new_size, (long) (sizeof(duk_hstring *) * new_size), (long) new_used,
(long) (((double) new_used) / ((double) new_size) * 100.0)));
#endif
#if defined(DUK_USE_HEAPPTR16)
DUK_FREE(heap, heap->strtable16);
heap->strtable16 = new_entries;
#else
DUK_FREE(heap, heap->strtable);
heap->strtable = new_entries;
#endif
heap->st_size = new_size;
heap->st_used = new_used; /* may be less, since DELETED entries are NULLed by rehash */
return 0; /* OK */
resize_error:
DUK_FREE(heap, new_entries);
return 1; /* FAIL */
}
DUK_LOCAL duk_bool_t duk__resize_strtab_probe(duk_heap *heap) {
duk_uint32_t new_size;
duk_bool_t ret;
new_size = (duk_uint32_t) duk__count_used_probe(heap);
if (new_size >= 0x80000000UL) {
new_size = DUK_STRTAB_HIGHEST_32BIT_PRIME;
} else {
new_size = duk_util_get_hash_prime(DUK_STRTAB_GROW_ST_SIZE(new_size));
new_size = duk_util_get_hash_prime(new_size);
}
DUK_ASSERT(new_size > 0);
/* rehash even if old and new sizes are the same to get rid of
* DELETED entries.
*/
ret = duk__resize_strtab_raw_probe(heap, new_size);
return ret;
}
DUK_INTERNAL void duk_heap_dump_strtab(duk_heap *heap) {
duk_strtab_entry *e;
duk_small_uint_t i;
duk_size_t j, n, used;
#if defined(DUK_USE_HEAPPTR16)
duk_uint16_t *lst;
duk_uint16_t null16 = heap->heapptr_null16;
#else
duk_hstring **lst;
#endif
DUK_ASSERT(heap != NULL);
for (i = 0; i < DUK_STRTAB_CHAIN_SIZE; i++) {
e = heap->strtable + i;
if (e->listlen == 0) {
#if defined(DUK_USE_HEAPPTR16)
DUK_DD(DUK_DDPRINT("[%03d] -> plain %d", (int) i, (int) (e->u.str16 != null16 ? 1 : 0)));
#else
DUK_DD(DUK_DDPRINT("[%03d] -> plain %d", (int) i, (int) (e->u.str ? 1 : 0)));
#endif
} else {
used = 0;
#if defined(DUK_USE_HEAPPTR16)
lst = (duk_uint16_t *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, e->u.strlist16);
#else
lst = e->u.strlist;
#endif
DUK_ASSERT(lst != NULL);
for (j = 0, n = e->listlen; j < n; j++) {
#if defined(DUK_USE_HEAPPTR16)
if (lst[j] != null16) {
#else
if (lst[j] != NULL) {
#endif
used++;
}
}
DUK_DD(DUK_DDPRINT("[%03d] -> array %d/%d", (int) i, (int) used, (int) e->listlen));
}
}
}
#endif /* DUK_USE_DEBUG */
#endif /* DUK_USE_STRTAB_CHAIN */
/*
* String table algorithm: closed hashing with a probe sequence
*
* This is the default algorithm and works fine for environments with
* minimal memory constraints.
*/
#if defined(DUK_USE_STRTAB_PROBE)
/* Count actually used (non-NULL, non-DELETED) entries. */
DUK_LOCAL duk_int_t duk__count_used_probe(duk_heap *heap) {
duk_int_t res = 0;
duk_uint_fast32_t i, n;
#if defined(DUK_USE_HEAPPTR16)
duk_uint16_t null16 = heap->heapptr_null16;
duk_uint16_t deleted16 = heap->heapptr_deleted16;
#endif
n = (duk_uint_fast32_t) heap->st_size;
for (i = 0; i < n; i++) {
#if defined(DUK_USE_HEAPPTR16)
if (heap->strtable16[i] != null16 && heap->strtable16[i] != deleted16) {
#else
if (heap->strtable[i] != NULL && heap->strtable[i] != DUK__DELETED_MARKER(heap)) {
#endif
res++;
}
}
return res;
}
#if defined(DUK_USE_HEAPPTR16)
DUK_LOCAL void duk__insert_hstring_probe(duk_heap *heap, duk_uint16_t *entries16, duk_uint32_t size, duk_uint32_t *p_used, duk_hstring *h) {
#else
DUK_LOCAL void duk__insert_hstring_probe(duk_heap *heap, duk_hstring **entries, duk_uint32_t size, duk_uint32_t *p_used, duk_hstring *h) {
#endif
duk_uint32_t i;
duk_uint32_t step;
#if defined(DUK_USE_HEAPPTR16)
duk_uint16_t null16 = heap->heapptr_null16;
duk_uint16_t deleted16 = heap->heapptr_deleted16;
#endif
DUK_ASSERT(size > 0);
i = DUK__HASH_INITIAL(DUK_HSTRING_GET_HASH(h), size);
step = DUK__HASH_PROBE_STEP(DUK_HSTRING_GET_HASH(h));
for (;;) {
#if defined(DUK_USE_HEAPPTR16)
duk_uint16_t e16 = entries16[i];
#else
duk_hstring *e = entries[i];
#endif
#if defined(DUK_USE_HEAPPTR16)
/* XXX: could check for e16 == 0 because NULL is guaranteed to
* encode to zero.
*/
if (e16 == null16) {
#else
if (e == NULL) {
#endif
DUK_DDD(DUK_DDDPRINT("insert hit (null): %ld", (long) i));
#if defined(DUK_USE_HEAPPTR16)
entries16[i] = DUK_USE_HEAPPTR_ENC16(heap->heap_udata, (void *) h);
#else
entries[i] = h;
#endif
(*p_used)++;
break;
#if defined(DUK_USE_HEAPPTR16)
} else if (e16 == deleted16) {
#else
} else if (e == DUK__DELETED_MARKER(heap)) {
#endif
/* st_used remains the same, DELETED is counted as used */
DUK_DDD(DUK_DDDPRINT("insert hit (deleted): %ld", (long) i));
#if defined(DUK_USE_HEAPPTR16)
entries16[i] = DUK_USE_HEAPPTR_ENC16(heap->heap_udata, (void *) h);
#else
entries[i] = h;
#endif
break;
}
DUK_DDD(DUK_DDDPRINT("insert miss: %ld", (long) i));
i = (i + step) % size;
/* looping should never happen */
DUK_ASSERT(i != DUK__HASH_INITIAL(DUK_HSTRING_GET_HASH(h), size));
}
}
#if defined(DUK_USE_HEAPPTR16)
DUK_LOCAL duk_hstring *duk__find_matching_string_probe(duk_heap *heap, duk_uint16_t *entries16, duk_uint32_t size, const duk_uint8_t *str, duk_uint32_t blen, duk_uint32_t strhash) {
#else
DUK_LOCAL duk_hstring *duk__find_matching_string_probe(duk_heap *heap, duk_hstring **entries, duk_uint32_t size, const duk_uint8_t *str, duk_uint32_t blen, duk_uint32_t strhash) {
#endif
duk_uint32_t i;
duk_uint32_t step;
DUK_ASSERT(size > 0);
i = DUK__HASH_INITIAL(strhash, size);
step = DUK__HASH_PROBE_STEP(strhash);
for (;;) {
duk_hstring *e;
#if defined(DUK_USE_HEAPPTR16)
e = (duk_hstring *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, entries16[i]);
#else
e = entries[i];
#endif
if (!e) {
return NULL;
}
if (e != DUK__DELETED_MARKER(heap) && DUK_HSTRING_GET_BYTELEN(e) == blen) {
if (DUK_MEMCMP((const void *) str, (const void *) DUK_HSTRING_GET_DATA(e), (size_t) blen) == 0) {
DUK_DDD(DUK_DDDPRINT("find matching hit: %ld (step %ld, size %ld)",
(long) i, (long) step, (long) size));
return e;
}
}
DUK_DDD(DUK_DDDPRINT("find matching miss: %ld (step %ld, size %ld)",
(long) i, (long) step, (long) size));
i = (i + step) % size;
/* looping should never happen */
DUK_ASSERT(i != DUK__HASH_INITIAL(strhash, size));
}
DUK_UNREACHABLE();
}
DUK_LOCAL void duk__sweep_stringtable(duk_heap *heap, duk_size_t *out_count_keep) {
duk_hstring *h;
duk_hstring *prev;
duk_uint32_t i;
#if defined(DUK_USE_DEBUG)
duk_size_t count_free = 0;
#endif
duk_size_t count_keep = 0;
DUK_DD(DUK_DDPRINT("duk__sweep_stringtable: %p", (void *) heap));
#if defined(DUK_USE_STRTAB_PTRCOMP)
if (heap->strtable16 == NULL) {
#else
if (heap->strtable == NULL) {
#endif
goto done;
}
for (i = 0; i < heap->st_size; i++) {
#if defined(DUK_USE_STRTAB_PTRCOMP)
h = DUK_USE_HEAPPTR_DEC16(heap->heap_udata, heap->strtable16[i]);
#else
h = heap->strtable[i];
#endif
prev = NULL;
while (h != NULL) {
duk_hstring *next;
next = h->hdr.h_next;
if (DUK_HEAPHDR_HAS_REACHABLE((duk_heaphdr *) h)) {
DUK_HEAPHDR_CLEAR_REACHABLE((duk_heaphdr *) h);
count_keep++;
prev = h;
} else {
#if defined(DUK_USE_DEBUG)
count_free++;
#endif
#if defined(DUK_USE_REFERENCE_COUNTING)
/* Non-zero refcounts should not happen for unreachable strings,
* because we refcount finalize all unreachable objects which
* should have decreased unreachable string refcounts to zero
* (even for cycles).
*/
DUK_ASSERT(DUK_HEAPHDR_GET_REFCOUNT((duk_heaphdr *) h) == 0);
#endif
/* deal with weak references first */
duk_heap_strcache_string_remove(heap, (duk_hstring *) h);
/* remove the string from the string table */
duk_heap_strtable_unlink_prev(heap, (duk_hstring *) h, (duk_hstring *) prev);
/* free inner references (these exist e.g. when external
* strings are enabled) and the struct itself.
*/
duk_free_hstring(heap, (duk_hstring *) h);
/* don't update 'prev'; it should be last string kept */
}
h = next;
}
}
done:
#if defined(DUK_USE_DEBUG)
DUK_D(DUK_DPRINT("mark-and-sweep sweep stringtable: %ld freed, %ld kept",
(long) count_free, (long) count_keep));
#endif
*out_count_keep = count_keep;
}
/*
* Sweep heap
*/
DUK_LOCAL void duk__sweep_heap(duk_heap *heap, duk_int_t flags, duk_size_t *out_count_keep) {
duk_heaphdr *prev; /* last element that was left in the heap */
duk_heaphdr *curr;
duk_heaphdr *next;
#if defined(DUK_USE_DEBUG)
duk_size_t count_free = 0;
duk_size_t count_finalize = 0;
duk_size_t count_rescue = 0;
#endif
duk_size_t count_keep = 0;
DUK_UNREF(flags);
DUK_DD(DUK_DDPRINT("duk__sweep_heap: %p", (void *) heap));
prev = NULL;
curr = heap->heap_allocated;
heap->heap_allocated = NULL;
while (curr) {
/* Strings and ROM objects are never placed on the heap allocated list. */
DUK_ASSERT(DUK_HEAPHDR_GET_TYPE(curr) != DUK_HTYPE_STRING);
DUK_ASSERT(!DUK_HEAPHDR_HAS_READONLY(curr));
next = DUK_HEAPHDR_GET_NEXT(heap, curr);
if (DUK_HEAPHDR_HAS_REACHABLE(curr)) {
/*
* Reachable object, keep
*/
DUK_DDD(DUK_DDDPRINT("sweep, reachable: %p", (void *) curr));
if (DUK_HEAPHDR_HAS_FINALIZABLE(curr)) {
/*
* If object has been marked finalizable, move it to the
* "to be finalized" work list. It will be collected on
* the next mark-and-sweep if it is still unreachable
* after running the finalizer.
*/
DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZED(curr));
DUK_ASSERT(DUK_HEAPHDR_GET_TYPE(curr) == DUK_HTYPE_OBJECT);
DUK_DDD(DUK_DDDPRINT("object has finalizer, move to finalization work list: %p", (void *) curr));
#if defined(DUK_USE_DOUBLE_LINKED_HEAP)
if (heap->finalize_list) {
DUK_HEAPHDR_SET_PREV(heap, heap->finalize_list, curr);
}
DUK_HEAPHDR_SET_PREV(heap, curr, NULL);
#endif
DUK_HEAPHDR_SET_NEXT(heap, curr, heap->finalize_list);
DUK_ASSERT_HEAPHDR_LINKS(heap, curr);
heap->finalize_list = curr;
#if defined(DUK_USE_DEBUG)
count_finalize++;
#endif
} else {
/*
* Object will be kept; queue object back to heap_allocated (to tail)
*/
if (DUK_HEAPHDR_HAS_FINALIZED(curr)) {
/*
* Object's finalizer was executed on last round, and
* object has been happily rescued.
*/
DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZABLE(curr));
DUK_ASSERT(DUK_HEAPHDR_GET_TYPE(curr) == DUK_HTYPE_OBJECT);
DUK_DD(DUK_DDPRINT("object rescued during mark-and-sweep finalization: %p", (void *) curr));
#if defined(DUK_USE_DEBUG)
count_rescue++;
#endif
} else {
/*
* Plain, boring reachable object.
*/
DUK_DD(DUK_DDPRINT("keep object: %!iO", curr));
count_keep++;
}
if (!heap->heap_allocated) {
heap->heap_allocated = curr;
}
if (prev) {
DUK_HEAPHDR_SET_NEXT(heap, prev, curr);
}
#if defined(DUK_USE_DOUBLE_LINKED_HEAP)
DUK_HEAPHDR_SET_PREV(heap, curr, prev);
#endif
DUK_ASSERT_HEAPHDR_LINKS(heap, prev);
DUK_ASSERT_HEAPHDR_LINKS(heap, curr);
prev = curr;
}
DUK_HEAPHDR_CLEAR_REACHABLE(curr);
DUK_HEAPHDR_CLEAR_FINALIZED(curr);
DUK_HEAPHDR_CLEAR_FINALIZABLE(curr);
DUK_ASSERT(!DUK_HEAPHDR_HAS_REACHABLE(curr));
DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZED(curr));
DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZABLE(curr));
curr = next;
} else {
/*
* Unreachable object, free
*/
DUK_DDD(DUK_DDDPRINT("sweep, not reachable: %p", (void *) curr));
#if defined(DUK_USE_REFERENCE_COUNTING)
/* Non-zero refcounts should not happen because we refcount
* finalize all unreachable objects which should cancel out
* refcounts (even for cycles).
*/
DUK_ASSERT(DUK_HEAPHDR_GET_REFCOUNT(curr) == 0);
#endif
DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZABLE(curr));
if (DUK_HEAPHDR_HAS_FINALIZED(curr)) {
DUK_DDD(DUK_DDDPRINT("finalized object not rescued: %p", (void *) curr));
}
/* Note: object cannot be a finalizable unreachable object, as
* they have been marked temporarily reachable for this round,
* and are handled above.
*/
#if defined(DUK_USE_DEBUG)
count_free++;
#endif
/* weak refs should be handled here, but no weak refs for
* any non-string objects exist right now.
*/
/* free object and all auxiliary (non-heap) allocs */
duk_heap_free_heaphdr_raw(heap, curr);
curr = next;
}
}
if (prev) {
DUK_HEAPHDR_SET_NEXT(heap, prev, NULL);
}
DUK_ASSERT_HEAPHDR_LINKS(heap, prev);
#if defined(DUK_USE_DEBUG)
DUK_D(DUK_DPRINT("mark-and-sweep sweep objects (non-string): %ld freed, %ld kept, %ld rescued, %ld queued for finalization",
(long) count_free, (long) count_keep, (long) count_rescue, (long) count_finalize));
#endif
*out_count_keep = count_keep;
}
DUK_LOCAL void duk__free_stringtable(duk_heap *heap) {
duk_uint_fast32_t i;
/* strings are only tracked by stringtable */
#if defined(DUK_USE_HEAPPTR16)
if (heap->strtable16) {
#else
if (heap->strtable) {
#endif
for (i = 0; i < (duk_uint_fast32_t) heap->st_size; i++) {
duk_hstring *e;
#if defined(DUK_USE_HEAPPTR16)
e = (duk_hstring *) DUK_USE_HEAPPTR_DEC16(heap->strtable16[i]);
#else
e = heap->strtable[i];
#endif
if (e == NULL || e == DUK_STRTAB_DELETED_MARKER(heap)) {
continue;
}
DUK_ASSERT(e != NULL);
/* strings may have inner refs (extdata) in some cases */
duk_free_hstring_inner(heap, (duk_hstring *) e);
DUK_DDD(DUK_DDDPRINT("FINALFREE (string): %!iO",
(duk_heaphdr *) e));
DUK_FREE(heap, e);
#if 0 /* not strictly necessary */
heap->strtable[i] = NULL;
#endif
}
#if defined(DUK_USE_HEAPPTR16)
DUK_FREE(heap, heap->strtable16);
#else
DUK_FREE(heap, heap->strtable);
#endif
#if 0 /* not strictly necessary */
heap->strtable = NULL;
#endif
}
}
DUK_LOCAL void duk__free_run_finalizers(duk_heap *heap) {
duk_hthread *thr;
duk_heaphdr *curr;
#ifdef DUK_USE_DEBUG
duk_size_t count_obj = 0;
#endif
DUK_ASSERT(heap != NULL);
DUK_ASSERT(heap->heap_thread != NULL);
#ifdef DUK_USE_REFERENCE_COUNTING
DUK_ASSERT(heap->refzero_list == NULL); /* refzero not running -> must be empty */
#endif
#ifdef DUK_USE_MARK_AND_SWEEP
DUK_ASSERT(heap->finalize_list == NULL); /* mark-and-sweep not running -> must be empty */
#endif
/* XXX: here again finalizer thread is the heap_thread which needs
* to be coordinated with finalizer thread fixes.
*/
thr = heap->heap_thread;
DUK_ASSERT(thr != NULL);
curr = heap->heap_allocated;
while (curr) {
if (DUK_HEAPHDR_GET_TYPE(curr) == DUK_HTYPE_OBJECT) {
/* Only objects in heap_allocated may have finalizers. Check that
* the object itself has a _Finalizer property so that we don't
* execute finalizers for e.g. Proxy objects.
*/
DUK_ASSERT(thr != NULL);
DUK_ASSERT(curr != NULL);
if (duk_hobject_hasprop_raw(thr, (duk_hobject *) curr, DUK_HTHREAD_STRING_INT_FINALIZER(thr))) {
duk_hobject_run_finalizer(thr, (duk_hobject *) curr);
}
#ifdef DUK_USE_DEBUG
count_obj++;
#endif
}
curr = DUK_HEAPHDR_GET_NEXT(curr);
}
/* Note: count includes all objects, not only those with an actual finalizer. */
#ifdef DUK_USE_DEBUG
DUK_D(DUK_DPRINT("checked %ld objects for finalizers before freeing heap", (long) count_obj));
#endif
}
DUK_LOCAL void duk__sweep_stringtable_probe(duk_heap *heap, duk_size_t *out_count_keep) {
duk_hstring *h;
duk_uint_fast32_t i;
#ifdef DUK_USE_DEBUG
duk_size_t count_free = 0;
#endif
duk_size_t count_keep = 0;
DUK_DD(DUK_DDPRINT("duk__sweep_stringtable: %p", (void *) heap));
for (i = 0; i < heap->st_size; i++) {
#if defined(DUK_USE_HEAPPTR16)
h = (duk_hstring *) DUK_USE_HEAPPTR_DEC16(heap->heap_udata, heap->strtable16[i]);
#else
h = heap->strtable[i];
#endif
if (h == NULL || h == DUK_STRTAB_DELETED_MARKER(heap)) {
continue;
} else if (DUK_HEAPHDR_HAS_REACHABLE((duk_heaphdr *) h)) {
DUK_HEAPHDR_CLEAR_REACHABLE((duk_heaphdr *) h);
count_keep++;
continue;
}
#ifdef DUK_USE_DEBUG
count_free++;
#endif
#if defined(DUK_USE_REFERENCE_COUNTING)
/* Non-zero refcounts should not happen for unreachable strings,
* because we refcount finalize all unreachable objects which
* should have decreased unreachable string refcounts to zero
* (even for cycles).
*/
DUK_ASSERT(DUK_HEAPHDR_GET_REFCOUNT((duk_heaphdr *) h) == 0);
#endif
DUK_DDD(DUK_DDDPRINT("sweep string, not reachable: %p", (void *) h));
/* deal with weak references first */
duk_heap_strcache_string_remove(heap, (duk_hstring *) h);
/* remove the string (mark DELETED), could also call
* duk_heap_string_remove() but that would be slow and
* pointless because we already know the slot.
*/
#if defined(DUK_USE_HEAPPTR16)
heap->strtable16[i] = heap->heapptr_deleted16;
#else
heap->strtable[i] = DUK_STRTAB_DELETED_MARKER(heap);
#endif
/* free inner references (these exist e.g. when external
* strings are enabled)
*/
duk_free_hstring_inner(heap, (duk_hstring *) h);
/* finally free the struct itself */
DUK_FREE(heap, h);
}
#ifdef DUK_USE_DEBUG
DUK_D(DUK_DPRINT("mark-and-sweep sweep stringtable: %ld freed, %ld kept",
(long) count_free, (long) count_keep));
#endif
*out_count_keep = count_keep;
}
