C++ DUK_DDPRINT函数代码示例

DUK_INTERNAL duk_ret_t duk_bi_object_constructor_seal_freeze_shared(duk_context *ctx) {
	duk_hthread *thr = (duk_hthread *) ctx;
	duk_hobject *h;
	duk_bool_t is_freeze;

	DUK_ASSERT_TOP(ctx, 1);

	is_freeze = (duk_bool_t) duk_get_current_magic(ctx);
	if (duk_is_buffer(ctx, 0)) {
		/* Plain buffer: already sealed, but not frozen (and can't be frozen
		 * because index properties can't be made non-writable.
		 */
		if (is_freeze) {
			goto fail_cannot_freeze;
		}
		return 1;
	} else if (duk_is_lightfunc(ctx, 0)) {
		/* Lightfunc: already sealed and frozen, success. */
		return 1;
	}
#if 0
	/* Seal/freeze are quite rare in practice so it'd be nice to get the
	 * correct behavior simply via automatic promotion (at the cost of some
	 * memory churn).  However, the promoted objects don't behave the same,
	 * e.g. promoted lightfuncs are extensible.
	 */
	h = duk_require_hobject_promote_mask(ctx, 0, DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER);
#endif

	h = duk_get_hobject(ctx, 0);
	if (h == NULL) {
		/* ES2015 Sections 19.1.2.5, 19.1.2.17 */
		return 1;
	}

	if (is_freeze && DUK_HOBJECT_IS_BUFOBJ(h)) {
		/* Buffer objects cannot be frozen because there's no internal
		 * support for making virtual array indices non-writable.
		 */
		DUK_DD(DUK_DDPRINT("cannot freeze a buffer object"));
		goto fail_cannot_freeze;
	}

	duk_hobject_object_seal_freeze_helper(thr, h, is_freeze);

	/* Sealed and frozen objects cannot gain any more properties,
	 * so this is a good time to compact them.
	 */
	duk_hobject_compact_props(thr, h);
	return 1;

 fail_cannot_freeze:
	DUK_DCERROR_TYPE_INVALID_ARGS(thr);  /* XXX: proper error message */
}

DUK_LOCAL void duk__mark_refzero_list(duk_heap *heap) {
	duk_heaphdr *hdr;

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

	hdr = heap->refzero_list;
	while (hdr) {
		duk__mark_heaphdr(heap, hdr);
		hdr = DUK_HEAPHDR_GET_NEXT(heap, hdr);
	}
}

DUK_LOCAL void duk__run_voluntary_gc(duk_heap *heap) {
	if (DUK_HEAP_HAS_MARKANDSWEEP_RUNNING(heap)) {
		DUK_DD(DUK_DDPRINT("mark-and-sweep in progress -> skip voluntary mark-and-sweep now"));
	} else {
		duk_small_uint_t flags;
		duk_bool_t rc;

		DUK_D(DUK_DPRINT("triggering voluntary mark-and-sweep"));
		flags = 0;
		rc = duk_heap_mark_and_sweep(heap, flags);
		DUK_UNREF(rc);
	}
}

DUK_LOCAL duk_ret_t duk__refcount_fake_finalizer(duk_context *ctx) {
	DUK_UNREF(ctx);
	DUK_D(DUK_DPRINT("fake refcount torture finalizer executed"));
#if 0
	DUK_DD(DUK_DDPRINT("fake torture finalizer for: %!T", duk_get_tval(ctx, 0)));
#endif
	/* Require a lot of stack to force a value stack grow/shrink. */
	duk_require_stack(ctx, 100000);

	/* XXX: do something to force a callstack grow/shrink, perhaps
	 * just a manual forced resize?
	 */
	return 0;
}

DUK_LOCAL void duk__clear_refzero_list_flags(duk_heap *heap) {
	duk_heaphdr *hdr;

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

	hdr = heap->refzero_list;
	while (hdr) {
		DUK_HEAPHDR_CLEAR_REACHABLE(hdr);
		DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZABLE(hdr));
		/* DUK_HEAPHDR_HAS_FINALIZED may or may not be set. */
		DUK_ASSERT(!DUK_HEAPHDR_HAS_TEMPROOT(hdr));
		hdr = DUK_HEAPHDR_GET_NEXT(heap, hdr);
	}
}

DUK_LOCAL void duk__clear_finalize_list_flags(duk_heap *heap) {
	duk_heaphdr *hdr;

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

	hdr = heap->finalize_list;
	while (hdr) {
		DUK_HEAPHDR_CLEAR_REACHABLE(hdr);
		DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZABLE(hdr));
		DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZED(hdr));
		DUK_ASSERT(!DUK_HEAPHDR_HAS_TEMPROOT(hdr));
		hdr = DUK_HEAPHDR_GET_NEXT(heap, hdr);
	}
}

DUK_LOCAL void duk__compact_object_list(duk_heap *heap, duk_hthread *thr, duk_heaphdr *start, duk_size_t *p_count_check, duk_size_t *p_count_compact, duk_size_t *p_count_bytes_saved) {
#else
DUK_LOCAL void duk__compact_object_list(duk_heap *heap, duk_hthread *thr, duk_heaphdr *start) {
#endif
	duk_heaphdr *curr;
#if defined(DUK_USE_DEBUG)
	duk_size_t old_size, new_size;
#endif
	duk_hobject *obj;

	DUK_UNREF(heap);

	curr = start;
	while (curr) {
		DUK_DDD(DUK_DDDPRINT("mark-and-sweep compact: %p", (void *) curr));

		if (DUK_HEAPHDR_GET_TYPE(curr) != DUK_HTYPE_OBJECT) {
			goto next;
		}
		obj = (duk_hobject *) curr;

#if defined(DUK_USE_DEBUG)
		old_size = DUK_HOBJECT_P_COMPUTE_SIZE(DUK_HOBJECT_GET_ESIZE(obj),
		                                      DUK_HOBJECT_GET_ASIZE(obj),
		                                      DUK_HOBJECT_GET_HSIZE(obj));
#endif

		DUK_DD(DUK_DDPRINT("compact object: %p", (void *) obj));
		duk_push_hobject((duk_context *) thr, obj);
		/* XXX: disable error handlers for duration of compaction? */
		duk_safe_call((duk_context *) thr, duk__protected_compact_object, NULL, 1, 0);

#if defined(DUK_USE_DEBUG)
		new_size = DUK_HOBJECT_P_COMPUTE_SIZE(DUK_HOBJECT_GET_ESIZE(obj),
		                                      DUK_HOBJECT_GET_ASIZE(obj),
		                                      DUK_HOBJECT_GET_HSIZE(obj));
#endif

#if defined(DUK_USE_DEBUG)
		(*p_count_compact)++;
		(*p_count_bytes_saved) += (duk_size_t) (old_size - new_size);
#endif

	 next:
		curr = DUK_HEAPHDR_GET_NEXT(heap, curr);
#if defined(DUK_USE_DEBUG)
		(*p_count_check)++;
#endif
	}
}

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;
}

static void duk__run_object_finalizers(duk_heap *heap) {
	duk_heaphdr *curr;
	duk_heaphdr *next;
#ifdef DUK_USE_DEBUG
	int count = 0;
#endif
	duk_hthread *thr;

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

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

	curr = heap->finalize_list;
	while (curr) {
		DUK_DDD(DUK_DDDPRINT("mark-and-sweep finalize: %p", (void *) curr));

		DUK_ASSERT(DUK_HEAPHDR_GET_TYPE(curr) == DUK_HTYPE_OBJECT);  /* only objects have finalizers */
		DUK_ASSERT(!DUK_HEAPHDR_HAS_REACHABLE(curr));                /* flags have been already cleared */
		DUK_ASSERT(!DUK_HEAPHDR_HAS_TEMPROOT(curr));
		DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZABLE(curr));
		DUK_ASSERT(!DUK_HEAPHDR_HAS_FINALIZED(curr));

		/* run the finalizer */
		duk_hobject_run_finalizer(thr, (duk_hobject *) curr);  /* must never longjmp */

		/* mark FINALIZED, for next mark-and-sweep (will collect unless has become reachable;
		 * prevent running finalizer again if reachable)
		 */
		DUK_HEAPHDR_SET_FINALIZED(curr);

		/* queue back to heap_allocated */
		next = DUK_HEAPHDR_GET_NEXT(curr);
		DUK_HEAP_INSERT_INTO_HEAP_ALLOCATED(heap, curr);

		curr = next;
#ifdef DUK_USE_DEBUG
		count++;
#endif
	}

	/* finalize_list will always be processed completely */
	heap->finalize_list = NULL;

#ifdef DUK_USE_DEBUG
	DUK_D(DUK_DPRINT("mark-and-sweep finalize objects: %d finalizers called", count));
#endif
}

DUK_INTERNAL void duk_heap_strcache_string_remove(duk_heap *heap, duk_hstring *h) {
    duk_small_int_t i;
    for (i = 0; i < DUK_HEAP_STRCACHE_SIZE; i++) {
        duk_strcache *c = heap->strcache + i;
        if (c->h == h) {
            DUK_DD(DUK_DDPRINT("deleting weak strcache reference to hstring %p from heap %p",
                               (void *) h, (void *) heap));
            c->h = NULL;

            /* XXX: the string shouldn't appear twice, but we now loop to the
             * end anyway; if fixed, add a looping assertion to ensure there
             * is no duplicate.
             */
        }
    }
}

DUK_LOCAL duk_hstring *duk__do_lookup(duk_heap *heap, const duk_uint8_t *str, duk_uint32_t blen, duk_uint32_t *out_strhash) {
	duk_hstring *res;

	DUK_ASSERT(out_strhash);

	*out_strhash = duk_heap_hashstring(heap, str, (duk_size_t) blen);

#if defined(DUK_USE_ROM_STRINGS)
	{
		duk_small_uint_t i;
		/* XXX: This is VERY inefficient now, and should be e.g. a
		 * binary search or perfect hash, to be fixed.
		 */
		for (i = 0; i < (duk_small_uint_t) (sizeof(duk_rom_strings) / sizeof(duk_hstring *)); i++) {
			duk_hstring *romstr;
			romstr = (duk_hstring *) duk_rom_strings[i];
			if (blen == DUK_HSTRING_GET_BYTELEN(romstr) &&
			    DUK_MEMCMP(str, (void *) DUK_HSTRING_GET_DATA(romstr), blen) == 0) {
				DUK_DD(DUK_DDPRINT("intern check: rom string: %!O, computed hash 0x%08lx, rom hash 0x%08lx",
				                   romstr, (unsigned long) *out_strhash, (unsigned long) DUK_HSTRING_GET_HASH(romstr)));
				DUK_ASSERT(*out_strhash == DUK_HSTRING_GET_HASH(romstr));
				*out_strhash = DUK_HSTRING_GET_HASH(romstr);
				return romstr;
			}
		}
	}
#endif  /* DUK_USE_ROM_STRINGS */

#if defined(DUK_USE_STRTAB_CHAIN)
	res = duk__find_matching_string_chain(heap, str, blen, *out_strhash);
#elif defined(DUK_USE_STRTAB_PROBE)
	res = duk__find_matching_string_probe(heap,
#if defined(DUK_USE_HEAPPTR16)
	                                      heap->strtable16,
#else
	                                      heap->strtable,
#endif
	                                      heap->st_size,
	                                      str,
	                                      blen,
	                                      *out_strhash);
#else
#error internal error, invalid strtab options
#endif

	return res;
}

DUK_LOCAL DUK_INLINE void duk__check_voluntary_gc(duk_heap *heap) {
	if (DUK_UNLIKELY(--(heap)->ms_trigger_counter < 0)) {
#if defined(DUK_USE_DEBUG)
		if (heap->ms_prevent_count == 0) {
			DUK_D(DUK_DPRINT("triggering voluntary mark-and-sweep"));
		} else {
			DUK_DD(DUK_DDPRINT("gc blocked -> skip voluntary mark-and-sweep now"));
		}
#endif

		/* Prevention checks in the call target handle cases where
		 * voluntary GC is not allowed.  The voluntary GC trigger
		 * counter is only rewritten if mark-and-sweep actually runs.
		 */
		duk_heap_mark_and_sweep(heap, DUK_MS_FLAG_VOLUNTARY /*flags*/);
	}
}

static void duk__mark_roots_heap(duk_heap *heap) {
	int i;

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

	duk__mark_heaphdr(heap, (duk_heaphdr *) heap->heap_thread);
	duk__mark_heaphdr(heap, (duk_heaphdr *) heap->heap_object);
	duk__mark_heaphdr(heap, (duk_heaphdr *) heap->log_buffer);

	for (i = 0; i < DUK_HEAP_NUM_STRINGS; i++) {
		duk_hstring *h = heap->strs[i];
		duk__mark_heaphdr(heap, (duk_heaphdr *) h);
	}

	duk__mark_tval(heap, &heap->lj.value1);
	duk__mark_tval(heap, &heap->lj.value2);
}

DUK_INTERNAL void duk_err_longjmp(duk_hthread *thr) {
	DUK_ASSERT(thr != NULL);

	DUK_DD(DUK_DDPRINT("longjmp error: type=%d iserror=%d value1=%!T value2=%!T",
	                   (int) thr->heap->lj.type, (int) thr->heap->lj.iserror,
	                   &thr->heap->lj.value1, &thr->heap->lj.value2));

#if !defined(DUK_USE_CPP_EXCEPTIONS)
	/* If we don't have a jmpbuf_ptr, there is little we can do except
	 * cause a fatal error.  The caller's expectation is that we never
	 * return.
	 *
	 * With C++ exceptions we now just propagate an uncaught error
	 * instead of invoking the fatal error handler.  Because there's
	 * a dummy jmpbuf for C++ exceptions now, this could be changed.
	 */
	if (!thr->heap->lj.jmpbuf_ptr) {
		DUK_D(DUK_DPRINT("uncaught error: type=%d iserror=%d value1=%!T value2=%!T",
		                 (int) thr->heap->lj.type, (int) thr->heap->lj.iserror,
		                 &thr->heap->lj.value1, &thr->heap->lj.value2));

#if defined(DUK_USE_PREFER_SIZE)
		duk__uncaught_minimal(thr);
#else
		duk__uncaught_error_aware(thr);
#endif
		DUK_UNREACHABLE();
	}
#endif  /* DUK_USE_CPP_EXCEPTIONS */

#if defined(DUK_USE_CPP_EXCEPTIONS)
	{
		duk_internal_exception exc;  /* dummy */
		throw exc;
	}
#else  /* DUK_USE_CPP_EXCEPTIONS */
	DUK_LONGJMP(thr->heap->lj.jmpbuf_ptr->jb);
#endif  /* DUK_USE_CPP_EXCEPTIONS */

	DUK_UNREACHABLE();
}

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));
	}
}