Example #1
0
	/*
	 *  String comparison (E5 Section 11.8.5, step 4), which
	 *  needs to compare codepoint by codepoint.
	 *
	 *  However, UTF-8 allows us to use strcmp directly: the shared
	 *  prefix will be encoded identically (UTF-8 has unique encoding)
	 *  and the first differing character can be compared with a simple
	 *  unsigned byte comparison (which strcmp does).
	 *
	 *  This will not work properly for non-xutf-8 strings, but this
	 *  is not an issue for compliance.
	 */

	DUK_ASSERT(h1 != NULL);
	DUK_ASSERT(h2 != NULL);

	return duk_js_data_compare((const duk_uint8_t *) DUK_HSTRING_GET_DATA(h1),
	                           (const duk_uint8_t *) DUK_HSTRING_GET_DATA(h2),
	                           (duk_size_t) DUK_HSTRING_GET_BYTELEN(h1),
	                           (duk_size_t) DUK_HSTRING_GET_BYTELEN(h2));
}

#if 0  /* unused */
DUK_INTERNAL duk_small_int_t duk_js_buffer_compare(duk_heap *heap, duk_hbuffer *h1, duk_hbuffer *h2) {
	/* Similar to String comparison. */

	DUK_ASSERT(h1 != NULL);
	DUK_ASSERT(h2 != NULL);
	DUK_UNREF(heap);

	return duk_js_data_compare((const duk_uint8_t *) DUK_HBUFFER_GET_DATA_PTR(heap, h1),
	                           (const duk_uint8_t *) DUK_HBUFFER_GET_DATA_PTR(heap, h2),
	                           (duk_size_t) DUK_HBUFFER_GET_SIZE(h1),
	                           (duk_size_t) DUK_HBUFFER_GET_SIZE(h2));
}
Example #2
0
DUK_LOCAL void duk__print_hbuffer(duk__dprint_state *st, duk_hbuffer *h) {
	duk_fixedbuffer *fb = st->fb;
	duk_size_t i, n;
	duk_uint8_t *p;

	if (duk_fb_is_full(fb)) {
		return;
	}

	/* terminal type: no depth check */

	if (!h) {
		duk_fb_put_cstring(fb, "NULL");
		return;
	}

	if (DUK_HBUFFER_HAS_DYNAMIC(h)) {
		if (DUK_HBUFFER_HAS_EXTERNAL(h)) {
			duk_hbuffer_external *g = (duk_hbuffer_external *) h;
			duk_fb_sprintf(fb, "buffer:external:%p:%ld",
			               (void *) DUK_HBUFFER_EXTERNAL_GET_DATA_PTR(NULL, g),
			               (long) DUK_HBUFFER_EXTERNAL_GET_SIZE(g));
		} else {
			duk_hbuffer_dynamic *g = (duk_hbuffer_dynamic *) h;
			duk_fb_sprintf(fb, "buffer:dynamic:%p:%ld",
			               (void *) DUK_HBUFFER_DYNAMIC_GET_DATA_PTR(NULL, g),
			               (long) DUK_HBUFFER_DYNAMIC_GET_SIZE(g));
		}
	} else {
		duk_fb_sprintf(fb, "buffer:fixed:%ld", (long) DUK_HBUFFER_GET_SIZE(h));
	}

#if defined(DUK_USE_REFERENCE_COUNTING)
	duk_fb_sprintf(fb, "/%lu", (unsigned long) DUK_HEAPHDR_GET_REFCOUNT(&h->hdr));
#endif

	if (st->hexdump) {
		duk_fb_sprintf(fb, "=[");
		n = DUK_HBUFFER_GET_SIZE(h);
		p = (duk_uint8_t *) DUK_HBUFFER_GET_DATA_PTR(NULL, h);
		for (i = 0; i < n; i++) {
			duk_fb_sprintf(fb, "%02lx", (unsigned long) p[i]);
		}
		duk_fb_sprintf(fb, "]");
	}
}
Example #3
0
DUK_LOCAL duk_uint8_t *duk__dump_hbuffer_raw(duk_hthread *thr, duk_uint8_t *p, duk_hbuffer *h) {
	duk_size_t len;
	duk_uint32_t tmp32;

	DUK_ASSERT(thr != NULL);
	DUK_ASSERT(h != NULL);
	DUK_UNREF(thr);

	len = DUK_HBUFFER_GET_SIZE(h);
	DUK_ASSERT(len <= 0xffffffffUL);  /* buffer limits */
	tmp32 = (duk_uint32_t) len;
	DUK_RAW_WRITE_U32_BE(p, tmp32);
	DUK_MEMCPY((void *) p,
	           (const void *) DUK_HBUFFER_GET_DATA_PTR(thr->heap, h),
	           len);
	p += len;
	return p;
}
Example #4
0
void duk_debug_dump_hobject(duk_hobject *obj) {
	duk_uint_fast32_t i;
	const char *str_empty = "";
	const char *str_excl = "!";

	DUK_D(DUK_DPRINT("=== hobject %p ===", (void *) obj));
	if (!obj) {
		return;
	}

	DUK_D(DUK_DPRINT("  %sextensible", DUK_HOBJECT_HAS_EXTENSIBLE(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sconstructable", DUK_HOBJECT_HAS_CONSTRUCTABLE(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sbound", DUK_HOBJECT_HAS_BOUND(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %scompiledfunction", DUK_HOBJECT_HAS_COMPILEDFUNCTION(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %snativefunction", DUK_HOBJECT_HAS_NATIVEFUNCTION(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sthread", DUK_HOBJECT_HAS_THREAD(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sarray_part", DUK_HOBJECT_HAS_ARRAY_PART(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sstrict", DUK_HOBJECT_HAS_STRICT(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %snewenv", DUK_HOBJECT_HAS_NEWENV(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %snamebinding", DUK_HOBJECT_HAS_NAMEBINDING(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %screateargs", DUK_HOBJECT_HAS_CREATEARGS(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %senvrecclosed", DUK_HOBJECT_HAS_ENVRECCLOSED(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sexotic_array", DUK_HOBJECT_HAS_EXOTIC_ARRAY(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sexotic_stringobj", DUK_HOBJECT_HAS_EXOTIC_STRINGOBJ(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sexotic_arguments", DUK_HOBJECT_HAS_EXOTIC_ARGUMENTS(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sexotic_dukfunc", DUK_HOBJECT_HAS_EXOTIC_DUKFUNC(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sexotic_bufferobj", DUK_HOBJECT_HAS_EXOTIC_BUFFEROBJ(obj) ? str_empty : str_excl));
	DUK_D(DUK_DPRINT("  %sexotic_proxyobj", DUK_HOBJECT_HAS_EXOTIC_PROXYOBJ(obj) ? str_empty : str_excl));

	DUK_D(DUK_DPRINT("  class: number %d -> %s",
	                 (int) DUK_HOBJECT_GET_CLASS_NUMBER(obj),
	                 duk__class_names[(DUK_HOBJECT_GET_CLASS_NUMBER(obj)) & ((1 << DUK_HOBJECT_FLAG_CLASS_BITS) - 1)]));

	DUK_D(DUK_DPRINT("  prototype: %p -> %!O",
	                 (void *) obj->prototype,
	                 (duk_heaphdr *) obj->prototype));

	DUK_D(DUK_DPRINT("  props: p=%p, e_size=%d, e_used=%d, a_size=%d, h_size=%d",
	                 (void *) obj->p,
	                 (int) obj->e_size,
	                 (int) obj->e_used,
	                 (int) obj->a_size,
	                 (int) obj->h_size));

	/*
	 *  Object (struct layout) specific dumping.  Inline code here
	 *  instead of helpers, to ensure debug line prefix is identical.
	 */

	if (DUK_HOBJECT_IS_COMPILEDFUNCTION(obj)) {
		duk_hcompiledfunction *h = (duk_hcompiledfunction *) obj;

		DUK_D(DUK_DPRINT("  hcompiledfunction"));
		DUK_D(DUK_DPRINT("  data: %!O", h->data));
		DUK_D(DUK_DPRINT("  nregs: %d", (int) h->nregs));
		DUK_D(DUK_DPRINT("  nargs: %d", (int) h->nargs));

		if (h->data && DUK_HBUFFER_HAS_DYNAMIC(h->data) && DUK_HBUFFER_GET_DATA_PTR(h->data)) {
			DUK_D(DUK_DPRINT("  consts: %p (%d, %d bytes)",
			                 (void *) DUK_HCOMPILEDFUNCTION_GET_CONSTS_BASE(h),
			                 (int) DUK_HCOMPILEDFUNCTION_GET_CONSTS_COUNT(h),
			                 (int) DUK_HCOMPILEDFUNCTION_GET_CONSTS_SIZE(h)));
			DUK_D(DUK_DPRINT("  funcs: %p (%d, %d bytes)",
			                 (void *) DUK_HCOMPILEDFUNCTION_GET_FUNCS_BASE(h),
			                 (int) DUK_HCOMPILEDFUNCTION_GET_FUNCS_COUNT(h),
			                 (int) DUK_HCOMPILEDFUNCTION_GET_FUNCS_SIZE(h)));
			DUK_D(DUK_DPRINT("  bytecode: %p (%d, %d bytes)",
			                 (void *) DUK_HCOMPILEDFUNCTION_GET_CODE_BASE(h),
			                 (int) DUK_HCOMPILEDFUNCTION_GET_CODE_COUNT(h),
			                 (int) DUK_HCOMPILEDFUNCTION_GET_CODE_SIZE(h)));
		} else {
			DUK_D(DUK_DPRINT("  consts: ???"));
			DUK_D(DUK_DPRINT("  funcs: ???"));
			DUK_D(DUK_DPRINT("  bytecode: ???"));
		}
	} else if (DUK_HOBJECT_IS_NATIVEFUNCTION(obj)) {
		duk_hnativefunction *h = (duk_hnativefunction *) obj;

		DUK_D(DUK_DPRINT("  hnativefunction"));
		/* XXX: h->func, cannot print function pointers portably */
		DUK_D(DUK_DPRINT("  nargs: %d", (int) h->nargs));
	} else if (DUK_HOBJECT_IS_THREAD(obj)) {
		duk_hthread *thr = (duk_hthread *) obj;
		duk_tval *p;

		DUK_D(DUK_DPRINT("  hthread"));
		DUK_D(DUK_DPRINT("  strict: %d", (int) thr->strict));
		DUK_D(DUK_DPRINT("  state: %d", (int) thr->state));

		DUK_D(DUK_DPRINT("  valstack_max: %d, callstack_max:%d, catchstack_max: %d",
		                 thr->valstack_max, thr->callstack_max, thr->catchstack_max));

		DUK_D(DUK_DPRINT("  callstack: ptr %p, size %d, top %d, preventcount %d, used size %d entries (%d bytes), alloc size %d entries (%d bytes)",
		                 (void *) thr->callstack,
		                 thr->callstack_size,
		                 thr->callstack_top,
		                 thr->callstack_preventcount,
		                 thr->callstack_top,
		                 thr->callstack_top * sizeof(duk_activation),
		                 thr->callstack_size,
		                 thr->callstack_size * sizeof(duk_activation)));

		DUK_DEBUG_SUMMARY_INIT();
		DUK_DEBUG_SUMMARY_CHAR('[');
		for (i = 0; i <= thr->callstack_size; i++) {
			if (i == thr->callstack_top) {
				DUK_DEBUG_SUMMARY_CHAR('|');
			}
			if (!thr->callstack) {
				DUK_DEBUG_SUMMARY_CHAR('@');
			} else if (i < thr->callstack_size) {
				if (i < thr->callstack_top) {
					/* tailcalling is nice to see immediately; other flags (e.g. strict)
					 * not that important.
					 */
					if (thr->callstack[i].flags & DUK_ACT_FLAG_TAILCALLED) {
						DUK_DEBUG_SUMMARY_CHAR('/');
					}
					DUK_DEBUG_SUMMARY_CHAR(duk__get_act_summary_char(&thr->callstack[i]));
				} else {
					DUK_DEBUG_SUMMARY_CHAR('.');
				}
			}
		}
		DUK_DEBUG_SUMMARY_CHAR(']');
		DUK_DEBUG_SUMMARY_FINISH();

		DUK_D(DUK_DPRINT("  valstack: ptr %p, end %p (%d), bottom %p (%d), top %p (%d), used size %d entries (%d bytes), alloc size %d entries (%d bytes)",
		                 (void *) thr->valstack,
		                 (void *) thr->valstack_end,
		                 (int) (thr->valstack_end - thr->valstack),
		                 (void *) thr->valstack_bottom,
		                 (int) (thr->valstack_bottom - thr->valstack),
		                 (void *) thr->valstack_top,
		                 (int) (thr->valstack_top - thr->valstack),
		                 (int) (thr->valstack_top - thr->valstack),
		                 (int) (thr->valstack_top - thr->valstack) * sizeof(duk_tval),
		                 (int) (thr->valstack_end - thr->valstack),
		                 (int) (thr->valstack_end - thr->valstack) * sizeof(duk_tval)));

		DUK_DEBUG_SUMMARY_INIT();
		DUK_DEBUG_SUMMARY_CHAR('[');
		p = thr->valstack;
		while (p <= thr->valstack_end) {
			i = (duk_uint_fast32_t) (p - thr->valstack);
			if (thr->callstack &&
			    thr->callstack_top > 0 &&
			    i == (duk_size_t) (thr->callstack + thr->callstack_top - 1)->idx_bottom) {
				DUK_DEBUG_SUMMARY_CHAR('>');
			}
			if (p == thr->valstack_top) {
				DUK_DEBUG_SUMMARY_CHAR('|');
			}
			if (p < thr->valstack_end) {
				if (p < thr->valstack_top) {
					DUK_DEBUG_SUMMARY_CHAR(duk__get_tval_summary_char(p));
				} else {
					/* XXX: safe printer for these?  would be nice, because
					 * we could visualize whether the values are in proper
					 * state.
					 */
					DUK_DEBUG_SUMMARY_CHAR('.');
				}
			}
			p++;
		}
		DUK_DEBUG_SUMMARY_CHAR(']');
		DUK_DEBUG_SUMMARY_FINISH();

		DUK_D(DUK_DPRINT("  catchstack: ptr %p, size %d, top %d, used size %d entries (%d bytes), alloc size %d entries (%d bytes)",
		                 (void *) thr->catchstack,
		                 thr->catchstack_size,
		                 thr->catchstack_top,
		                 thr->catchstack_top,
		                 thr->catchstack_top * sizeof(duk_catcher),
		                 thr->catchstack_size,
		                 thr->catchstack_size * sizeof(duk_catcher)));

		DUK_DEBUG_SUMMARY_INIT();
		DUK_DEBUG_SUMMARY_CHAR('[');
		for (i = 0; i <= thr->catchstack_size; i++) {
			if (i == thr->catchstack_top) {
				DUK_DEBUG_SUMMARY_CHAR('|');
			}
			if (!thr->catchstack) {
				DUK_DEBUG_SUMMARY_CHAR('@');
			} else if (i < thr->catchstack_size) {
				if (i < thr->catchstack_top) {
					DUK_DEBUG_SUMMARY_CHAR(duk__get_cat_summary_char(&thr->catchstack[i]));
				} else {
					DUK_DEBUG_SUMMARY_CHAR('.');
				}
			}
		}
		DUK_DEBUG_SUMMARY_CHAR(']');
		DUK_DEBUG_SUMMARY_FINISH();

		DUK_D(DUK_DPRINT("  resumer: ptr %p",
		                 (void *) thr->resumer));

#if 0  /* worth dumping? */
		for (i = 0; i < DUK_NUM_BUILTINS; i++) {
			DUK_D(DUK_DPRINT("  builtins[%d] -> %!@O", i, thr->builtins[i]));
		}
#endif
	}

	if (obj->p) {
		DUK_D(DUK_DPRINT("  props alloc size: %d",
		                 (int) DUK_HOBJECT_P_COMPUTE_SIZE(obj->e_size, obj->a_size, obj->h_size)));
	} else {
		DUK_D(DUK_DPRINT("  props alloc size: n/a"));
	}

	DUK_D(DUK_DPRINT("  prop entries:"));
	for (i = 0; i < obj->e_size; i++) {
		duk_hstring *k;
		duk_propvalue *v;

		k = DUK_HOBJECT_E_GET_KEY(obj, i);
		v = DUK_HOBJECT_E_GET_VALUE_PTR(obj, i);

		if (i >= obj->e_used) {
			DUK_D(DUK_DPRINT("    [%d]: UNUSED", i));
			continue;
		}

		if (!k) {
			DUK_D(DUK_DPRINT("    [%d]: NULL", i));
			continue;
		}

		if (DUK_HOBJECT_E_SLOT_IS_ACCESSOR(obj, i)) {
			DUK_D(DUK_DPRINT("    [%d]: [w=%d e=%d c=%d a=%d] %!O -> get:%p set:%p; get %!O; set %!O",
			                 i,
			                 DUK_HOBJECT_E_SLOT_IS_WRITABLE(obj, i),
			                 DUK_HOBJECT_E_SLOT_IS_ENUMERABLE(obj, i),
			                 DUK_HOBJECT_E_SLOT_IS_CONFIGURABLE(obj, i),
			                 DUK_HOBJECT_E_SLOT_IS_ACCESSOR(obj, i),
			                 k,
			                 (void *) v->a.get,
			                 (void *) v->a.set,
			                 (duk_heaphdr *) v->a.get,
			                 (duk_heaphdr *) v->a.set));
		} else {
			DUK_D(DUK_DPRINT("    [%d]: [w=%d e=%d c=%d a=%d] %!O -> %!T",
			                 i,
			                 DUK_HOBJECT_E_SLOT_IS_WRITABLE(obj, i),
			                 DUK_HOBJECT_E_SLOT_IS_ENUMERABLE(obj, i),
			                 DUK_HOBJECT_E_SLOT_IS_CONFIGURABLE(obj, i),
			                 DUK_HOBJECT_E_SLOT_IS_ACCESSOR(obj, i),
			                 k,
			                 &v->v));
		}
	}

	DUK_D(DUK_DPRINT("  array entries:"));
	for (i = 0; i < obj->a_size; i++) {
		DUK_D(DUK_DPRINT("    [%d]: [w=%d e=%d c=%d a=%d] %d -> %!T",
		                 i,
		                 1,  /* implicit attributes */
		                 1,
		                 1,
		                 0,
		                 i,
		                 DUK_HOBJECT_A_GET_VALUE_PTR(obj, i)));
	}

	DUK_D(DUK_DPRINT("  hash entries:"));
	for (i = 0; i < obj->h_size; i++) {
		duk_uint32_t t = DUK_HOBJECT_H_GET_INDEX(obj, i);
		if (t == DUK_HOBJECT_HASHIDX_UNUSED) {
			DUK_D(DUK_DPRINT("    [%d]: unused", i));
		} else if (t == DUK_HOBJECT_HASHIDX_DELETED) {
			DUK_D(DUK_DPRINT("    [%d]: deleted", i));
		} else {
			DUK_D(DUK_DPRINT("    [%d]: %d",
			                 i,
			                 (int) t));
		}
	}
}
Example #5
0
DUK_INTERNAL duk_bool_t duk_js_equals_helper(duk_hthread *thr, duk_tval *tv_x, duk_tval *tv_y, duk_small_int_t flags) {
	duk_context *ctx = (duk_context *) thr;
	duk_tval *tv_tmp;

	/* If flags != 0 (strict or SameValue), thr can be NULL.  For loose
	 * equals comparison it must be != NULL.
	 */
	DUK_ASSERT(flags != 0 || thr != NULL);

	/*
	 *  Same type?
	 *
	 *  Note: since number values have no explicit tag in the 8-byte
	 *  representation, need the awkward if + switch.
	 */

#if defined(DUK_USE_FASTINT)
	if (DUK_TVAL_IS_FASTINT(tv_x) && DUK_TVAL_IS_FASTINT(tv_y)) {
		if (DUK_TVAL_GET_FASTINT(tv_x) == DUK_TVAL_GET_FASTINT(tv_y)) {
			return 1;
		} else {
			return 0;
		}
	}
	else
#endif
	if (DUK_TVAL_IS_NUMBER(tv_x) && DUK_TVAL_IS_NUMBER(tv_y)) {
		/* Catches both doubles and cases where only one argument is a fastint */
		if (DUK_UNLIKELY((flags & DUK_EQUALS_FLAG_SAMEVALUE) != 0)) {
			/* SameValue */
			return duk__js_samevalue_number(DUK_TVAL_GET_NUMBER(tv_x),
			                                DUK_TVAL_GET_NUMBER(tv_y));
		} else {
			/* equals and strict equals */
			return duk__js_equals_number(DUK_TVAL_GET_NUMBER(tv_x),
			                             DUK_TVAL_GET_NUMBER(tv_y));
		}
	} else if (DUK_TVAL_GET_TAG(tv_x) == DUK_TVAL_GET_TAG(tv_y)) {
		switch (DUK_TVAL_GET_TAG(tv_x)) {
		case DUK_TAG_UNDEFINED:
		case DUK_TAG_NULL: {
			return 1;
		}
		case DUK_TAG_BOOLEAN: {
			return DUK_TVAL_GET_BOOLEAN(tv_x) == DUK_TVAL_GET_BOOLEAN(tv_y);
		}
		case DUK_TAG_POINTER: {
			return DUK_TVAL_GET_POINTER(tv_x) == DUK_TVAL_GET_POINTER(tv_y);
		}
		case DUK_TAG_STRING:
		case DUK_TAG_OBJECT: {
			/* heap pointer comparison suffices */
			return DUK_TVAL_GET_HEAPHDR(tv_x) == DUK_TVAL_GET_HEAPHDR(tv_y);
		}
		case DUK_TAG_BUFFER: {
			if ((flags & (DUK_EQUALS_FLAG_STRICT | DUK_EQUALS_FLAG_SAMEVALUE)) != 0) {
				/* heap pointer comparison suffices */
				return DUK_TVAL_GET_HEAPHDR(tv_x) == DUK_TVAL_GET_HEAPHDR(tv_y);
			} else {
				/* non-strict equality for buffers compares contents */
				duk_hbuffer *h_x = DUK_TVAL_GET_BUFFER(tv_x);
				duk_hbuffer *h_y = DUK_TVAL_GET_BUFFER(tv_y);
				duk_size_t len_x = DUK_HBUFFER_GET_SIZE(h_x);
				duk_size_t len_y = DUK_HBUFFER_GET_SIZE(h_y);
				void *buf_x;
				void *buf_y;
				if (len_x != len_y) {
					return 0;
				}
				buf_x = (void *) DUK_HBUFFER_GET_DATA_PTR(thr->heap, h_x);
				buf_y = (void *) DUK_HBUFFER_GET_DATA_PTR(thr->heap, h_y);
				/* if len_x == len_y == 0, buf_x and/or buf_y may
				 * be NULL, but that's OK.
				 */
				DUK_ASSERT(len_x == len_y);
				DUK_ASSERT(len_x == 0 || buf_x != NULL);
				DUK_ASSERT(len_y == 0 || buf_y != NULL);
				return (DUK_MEMCMP(buf_x, buf_y, len_x) == 0) ? 1 : 0;
			}
		}
		case DUK_TAG_LIGHTFUNC: {
			/* At least 'magic' has a significant impact on function
			 * identity.
			 */
			duk_small_uint_t lf_flags_x;
			duk_small_uint_t lf_flags_y;
			duk_c_function func_x;
			duk_c_function func_y;

			DUK_TVAL_GET_LIGHTFUNC(tv_x, func_x, lf_flags_x);
			DUK_TVAL_GET_LIGHTFUNC(tv_y, func_y, lf_flags_y);
			return ((func_x == func_y) && (lf_flags_x == lf_flags_y)) ? 1 : 0;
		}
#if defined(DUK_USE_FASTINT)
		case DUK_TAG_FASTINT:
#endif
		default: {
			DUK_ASSERT(DUK_TVAL_IS_NUMBER(tv_x));
			DUK_ASSERT(DUK_TVAL_IS_NUMBER(tv_y));
			DUK_UNREACHABLE();
			return 0;
		}
		}
	}

	if ((flags & (DUK_EQUALS_FLAG_STRICT | DUK_EQUALS_FLAG_SAMEVALUE)) != 0) {
		return 0;
	}

	DUK_ASSERT(flags == 0);  /* non-strict equality from here on */

	/*
	 *  Types are different; various cases for non-strict comparison
	 *
	 *  Since comparison is symmetric, we use a "swap trick" to reduce
	 *  code size.
	 */

	/* Undefined/null are considered equal (e.g. "null == undefined" -> true). */
	if ((DUK_TVAL_IS_UNDEFINED(tv_x) && DUK_TVAL_IS_NULL(tv_y)) ||
	    (DUK_TVAL_IS_NULL(tv_x) && DUK_TVAL_IS_UNDEFINED(tv_y))) {
		return 1;
	}

	/* Number/string-or-buffer -> coerce string to number (e.g. "'1.5' == 1.5" -> true). */
	if (DUK_TVAL_IS_NUMBER(tv_x) && (DUK_TVAL_IS_STRING(tv_y) || DUK_TVAL_IS_BUFFER(tv_y))) {
		/* the next 'if' is guaranteed to match after swap */
		tv_tmp = tv_x;
		tv_x = tv_y;
		tv_y = tv_tmp;
	}
	if ((DUK_TVAL_IS_STRING(tv_x) || DUK_TVAL_IS_BUFFER(tv_x)) && DUK_TVAL_IS_NUMBER(tv_y)) {
		/* XXX: this is possible without resorting to the value stack */
		duk_double_t d1, d2;
		d2 = DUK_TVAL_GET_NUMBER(tv_y);
		duk_push_tval(ctx, tv_x);
		duk_to_string(ctx, -1);  /* buffer values are coerced first to string here */
		duk_to_number(ctx, -1);
		d1 = duk_require_number(ctx, -1);
		duk_pop(ctx);
		return duk__js_equals_number(d1, d2);
	}

	/* Buffer/string -> compare contents. */
	if (DUK_TVAL_IS_BUFFER(tv_x) && DUK_TVAL_IS_STRING(tv_y)) {
		tv_tmp = tv_x;
		tv_x = tv_y;
		tv_y = tv_tmp;
	}
	if (DUK_TVAL_IS_STRING(tv_x) && DUK_TVAL_IS_BUFFER(tv_y)) {
		duk_hstring *h_x = DUK_TVAL_GET_STRING(tv_x);
		duk_hbuffer *h_y = DUK_TVAL_GET_BUFFER(tv_y);
		duk_size_t len_x = DUK_HSTRING_GET_BYTELEN(h_x);
		duk_size_t len_y = DUK_HBUFFER_GET_SIZE(h_y);
		void *buf_x;
		void *buf_y;
		if (len_x != len_y) {
			return 0;
		}
		buf_x = (void *) DUK_HSTRING_GET_DATA(h_x);
		buf_y = (void *) DUK_HBUFFER_GET_DATA_PTR(thr->heap, h_y);
		/* if len_x == len_y == 0, buf_x and/or buf_y may
		 * be NULL, but that's OK.
		 */
		DUK_ASSERT(len_x == len_y);
		DUK_ASSERT(len_x == 0 || buf_x != NULL);
		DUK_ASSERT(len_y == 0 || buf_y != NULL);
		return (DUK_MEMCMP(buf_x, buf_y, len_x) == 0) ? 1 : 0;
	}

	/* Boolean/any -> coerce boolean to number and try again.  If boolean is
	 * compared to a pointer, the final comparison after coercion now always
	 * yields false (as pointer vs. number compares to false), but this is
	 * not special cased.
	 */
	if (DUK_TVAL_IS_BOOLEAN(tv_x)) {
		tv_tmp = tv_x;
		tv_x = tv_y;
		tv_y = tv_tmp;
	}
	if (DUK_TVAL_IS_BOOLEAN(tv_y)) {
		/* ToNumber(bool) is +1.0 or 0.0.  Tagged boolean value is always 0 or 1. */
		duk_bool_t rc;
		DUK_ASSERT(DUK_TVAL_GET_BOOLEAN(tv_y) == 0 || DUK_TVAL_GET_BOOLEAN(tv_y) == 1);
		duk_push_tval(ctx, tv_x);
		duk_push_int(ctx, DUK_TVAL_GET_BOOLEAN(tv_y));
		rc = duk_js_equals_helper(thr, duk_get_tval(ctx, -2), duk_get_tval(ctx, -1), 0 /*flags:nonstrict*/);
		duk_pop_2(ctx);
		return rc;
	}

	/* String-number-buffer/object -> coerce object to primitive (apparently without hint), then try again. */
	if ((DUK_TVAL_IS_STRING(tv_x) || DUK_TVAL_IS_NUMBER(tv_x) || DUK_TVAL_IS_BUFFER(tv_x)) &&
	    DUK_TVAL_IS_OBJECT(tv_y)) {
		tv_tmp = tv_x;
		tv_x = tv_y;
		tv_y = tv_tmp;
	}
	if (DUK_TVAL_IS_OBJECT(tv_x) &&
	    (DUK_TVAL_IS_STRING(tv_y) || DUK_TVAL_IS_NUMBER(tv_y) || DUK_TVAL_IS_BUFFER(tv_y))) {
		duk_bool_t rc;
		duk_push_tval(ctx, tv_x);
		duk_push_tval(ctx, tv_y);
		duk_to_primitive(ctx, -2, DUK_HINT_NONE);  /* apparently no hint? */
		rc = duk_js_equals_helper(thr, duk_get_tval(ctx, -2), duk_get_tval(ctx, -1), 0 /*flags:nonstrict*/);
		duk_pop_2(ctx);
		return rc;
	}

	/* Nothing worked -> not equal. */
	return 0;
}