예제 #1
0
DUK_LOCAL void duk__mark_finalizable(duk_heap *heap) {
	duk_hthread *thr;
	duk_heaphdr *hdr;
	duk_size_t count_finalizable = 0;

	DUK_DD(DUK_DDPRINT("duk__mark_finalizable: %p", (void *) heap));

	thr = duk__get_temp_hthread(heap);
	DUK_ASSERT(thr != NULL);

	hdr = heap->heap_allocated;
	while (hdr) {
		/* A finalizer is looked up from the object and up its prototype chain
		 * (which allows inherited finalizers).  A prototype loop must not cause
		 * an error to be thrown here; duk_hobject_hasprop_raw() will ignore a
		 * prototype loop silently and indicate that the property doesn't exist.
		 */

		if (!DUK_HEAPHDR_HAS_REACHABLE(hdr) &&
		    DUK_HEAPHDR_GET_TYPE(hdr) == DUK_HTYPE_OBJECT &&
		    !DUK_HEAPHDR_HAS_FINALIZED(hdr) &&
		    duk_hobject_hasprop_raw(thr, (duk_hobject *) hdr, DUK_HTHREAD_STRING_INT_FINALIZER(thr))) {

			/* heaphdr:
			 *  - is not reachable
			 *  - is an object
			 *  - is not a finalized object
			 *  - has a finalizer
			 */

			DUK_DD(DUK_DDPRINT("unreachable heap object will be "
			                   "finalized -> mark as finalizable "
			                   "and treat as a reachability root: %p",
			                   (void *) hdr));
			DUK_ASSERT(!DUK_HEAPHDR_HAS_READONLY(hdr));
			DUK_HEAPHDR_SET_FINALIZABLE(hdr);
			count_finalizable ++;
		}

		hdr = DUK_HEAPHDR_GET_NEXT(heap, hdr);
	}

	if (count_finalizable == 0) {
		return;
	}

	DUK_DD(DUK_DDPRINT("marked %ld heap objects as finalizable, now mark them reachable",
	                   (long) count_finalizable));

	hdr = heap->heap_allocated;
	while (hdr) {
		if (DUK_HEAPHDR_HAS_FINALIZABLE(hdr)) {
			duk__mark_heaphdr(heap, hdr);
		}

		hdr = DUK_HEAPHDR_GET_NEXT(heap, hdr);
	}

	/* Caller will finish the marking process if we hit a recursion limit. */
}
예제 #2
0
static void duk__mark_finalizable(duk_heap *heap) {
	duk_hthread *thr;
	duk_heaphdr *hdr;
	int count_finalizable = 0;

	DUK_DD(DUK_DDPRINT("duk__mark_finalizable: %p", (void *) heap));

	thr = duk__get_temp_hthread(heap);
	DUK_ASSERT(thr != NULL);

	hdr = heap->heap_allocated;
	while (hdr) {
		/* A finalizer is looked up from the object and up its prototype chain
		 * (which allows inherited finalizers).
		 */
		if (!DUK_HEAPHDR_HAS_REACHABLE(hdr) &&
		    DUK_HEAPHDR_GET_TYPE(hdr) == DUK_HTYPE_OBJECT &&
		    !DUK_HEAPHDR_HAS_FINALIZED(hdr) &&
		    duk_hobject_hasprop_raw(thr, (duk_hobject *) hdr, DUK_HTHREAD_STRING_INT_FINALIZER(thr))) {

			/* heaphdr:
			 *  - is not reachable
			 *  - is an object
			 *  - is not a finalized object
			 *  - has a finalizer
			 */

			DUK_DD(DUK_DDPRINT("unreachable heap object will be finalized -> mark as finalizable and treat as a reachability root: %p", hdr));
			DUK_HEAPHDR_SET_FINALIZABLE(hdr);
			count_finalizable ++;
		}

		hdr = DUK_HEAPHDR_GET_NEXT(hdr);
	}

	if (count_finalizable == 0) {
		return;
	}

	DUK_DD(DUK_DDPRINT("marked %d heap objects as finalizable, now mark them reachable", count_finalizable));

	hdr = heap->heap_allocated;
	while (hdr) {
		if (DUK_HEAPHDR_HAS_FINALIZABLE(hdr)) {
			duk__mark_heaphdr(heap, hdr);
		}

		hdr = DUK_HEAPHDR_GET_NEXT(hdr);
	}

	/* Caller will finish the marking process if we hit a recursion limit. */
}