DUK_LOCAL duk_small_int_t duk__array_sort_compare(duk_context *ctx, duk_int_t idx1, duk_int_t idx2) {
duk_bool_t have1, have2;
duk_bool_t undef1, undef2;
duk_small_int_t ret;
duk_idx_t idx_obj = 1; /* fixed offsets in valstack */
duk_idx_t idx_fn = 0;
duk_hstring *h1, *h2;
/* Fast exit if indices are identical. This is valid for a non-existent property,
* for an undefined value, and almost always for ToString() coerced comparison of
* arbitrary values (corner cases where this is not the case include e.g. a an
* object with varying ToString() coercion).
*
* The specification does not prohibit "caching" of values read from the array, so
* assuming equality for comparing an index with itself falls into the category of
* "caching".
*
* Also, compareFn may be inconsistent, so skipping a call to compareFn here may
* have an effect on the final result. The specification does not require any
* specific behavior for inconsistent compare functions, so again, this fast path
* is OK.
*/
if (idx1 == idx2) {
DUK_DDD(DUK_DDDPRINT("duk__array_sort_compare: idx1=%ld, idx2=%ld -> indices identical, quick exit",
(long) idx1, (long) idx2));
return 0;
}
have1 = duk_get_prop_index(ctx, idx_obj, (duk_uarridx_t) idx1);
have2 = duk_get_prop_index(ctx, idx_obj, (duk_uarridx_t) idx2);
DUK_DDD(DUK_DDDPRINT("duk__array_sort_compare: idx1=%ld, idx2=%ld, have1=%ld, have2=%ld, val1=%!T, val2=%!T",
(long) idx1, (long) idx2, (long) have1, (long) have2,
(duk_tval *) duk_get_tval(ctx, -2), (duk_tval *) duk_get_tval(ctx, -1)));
if (have1) {
if (have2) {
;
} else {
ret = -1;
goto pop_ret;
}
} else {
if (have2) {
ret = 1;
goto pop_ret;
} else {
ret = 0;
goto pop_ret;
}
}
undef1 = duk_is_undefined(ctx, -2);
undef2 = duk_is_undefined(ctx, -1);
if (undef1) {
if (undef2) {
ret = 0;
goto pop_ret;
} else {
ret = 1;
goto pop_ret;
}
} else {
if (undef2) {
ret = -1;
goto pop_ret;
} else {
;
}
}
if (!duk_is_undefined(ctx, idx_fn)) {
duk_double_t d;
/* no need to check callable; duk_call() will do that */
duk_dup(ctx, idx_fn); /* -> [ ... x y fn ] */
duk_insert(ctx, -3); /* -> [ ... fn x y ] */
duk_call(ctx, 2); /* -> [ ... res ] */
/* The specification is a bit vague what to do if the return
* value is not a number. Other implementations seem to
* tolerate non-numbers but e.g. V8 won't apparently do a
* ToNumber().
*/
/* XXX: best behavior for real world compatibility? */
d = duk_to_number(ctx, -1);
if (d < 0.0) {
ret = -1;
} else if (d > 0.0) {
ret = 1;
} else {
ret = 0;
}
duk_pop(ctx);
DUK_DDD(DUK_DDDPRINT("-> result %ld (from comparefn, after coercion)", (long) ret));
return ret;
}
/* string compare is the default (a bit oddly) */
h1 = duk_to_hstring(ctx, -2);
h2 = duk_to_hstring(ctx, -1);
DUK_ASSERT(h1 != NULL);
DUK_ASSERT(h2 != NULL);
ret = duk_js_string_compare(h1, h2); /* retval is directly usable */
goto pop_ret;
pop_ret:
duk_pop_2(ctx);
DUK_DDD(DUK_DDDPRINT("-> result %ld", (long) ret));
return ret;
}
DUK_INTERNAL duk_bool_t duk_js_compare_helper(duk_hthread *thr, duk_tval *tv_x, duk_tval *tv_y, duk_small_int_t flags) {
duk_context *ctx = (duk_context *) thr;
duk_double_t d1, d2;
duk_small_int_t c1, c2;
duk_small_int_t s1, s2;
duk_small_int_t rc;
duk_bool_t retval;
/* Fast path for fastints */
#if defined(DUK_USE_FASTINT)
if (DUK_TVAL_IS_FASTINT(tv_x) && DUK_TVAL_IS_FASTINT(tv_y)) {
duk_int64_t v1 = DUK_TVAL_GET_FASTINT(tv_x);
duk_int64_t v2 = DUK_TVAL_GET_FASTINT(tv_y);
if (v1 < v2) {
/* 'lt is true' */
retval = 1;
} else {
retval = 0;
}
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval ^= 1;
}
return retval;
}
#endif /* DUK_USE_FASTINT */
/* Fast path for numbers (one of which may be a fastint) */
#if 1 /* XXX: make fast paths optional for size minimization? */
if (DUK_TVAL_IS_NUMBER(tv_x) && DUK_TVAL_IS_NUMBER(tv_y)) {
d1 = DUK_TVAL_GET_NUMBER(tv_x);
d2 = DUK_TVAL_GET_NUMBER(tv_y);
c1 = DUK_FPCLASSIFY(d1);
c2 = DUK_FPCLASSIFY(d2);
if (c1 == DUK_FP_NORMAL && c2 == DUK_FP_NORMAL) {
/* XXX: this is a very narrow check, and doesn't cover
* zeroes, subnormals, infinities, which compare normally.
*/
if (d1 < d2) {
/* 'lt is true' */
retval = 1;
} else {
retval = 0;
}
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval ^= 1;
}
return retval;
}
}
#endif
/* Slow path */
duk_push_tval(ctx, tv_x);
duk_push_tval(ctx, tv_y);
if (flags & DUK_COMPARE_FLAG_EVAL_LEFT_FIRST) {
duk_to_primitive(ctx, -2, DUK_HINT_NUMBER);
duk_to_primitive(ctx, -1, DUK_HINT_NUMBER);
} else {
duk_to_primitive(ctx, -1, DUK_HINT_NUMBER);
duk_to_primitive(ctx, -2, DUK_HINT_NUMBER);
}
/* Note: reuse variables */
tv_x = duk_get_tval(ctx, -2);
tv_y = duk_get_tval(ctx, -1);
if (DUK_TVAL_IS_STRING(tv_x) && DUK_TVAL_IS_STRING(tv_y)) {
duk_hstring *h1 = DUK_TVAL_GET_STRING(tv_x);
duk_hstring *h2 = DUK_TVAL_GET_STRING(tv_y);
DUK_ASSERT(h1 != NULL);
DUK_ASSERT(h2 != NULL);
rc = duk_js_string_compare(h1, h2);
if (rc < 0) {
goto lt_true;
} else {
goto lt_false;
}
} else {
/* Ordering should not matter (E5 Section 11.8.5, step 3.a) but
* preserve it just in case.
*/
if (flags & DUK_COMPARE_FLAG_EVAL_LEFT_FIRST) {
d1 = duk_to_number(ctx, -2);
d2 = duk_to_number(ctx, -1);
} else {
d2 = duk_to_number(ctx, -1);
d1 = duk_to_number(ctx, -2);
}
c1 = (duk_small_int_t) DUK_FPCLASSIFY(d1);
s1 = (duk_small_int_t) DUK_SIGNBIT(d1);
c2 = (duk_small_int_t) DUK_FPCLASSIFY(d2);
s2 = (duk_small_int_t) DUK_SIGNBIT(d2);
if (c1 == DUK_FP_NAN || c2 == DUK_FP_NAN) {
goto lt_undefined;
}
if (c1 == DUK_FP_ZERO && c2 == DUK_FP_ZERO) {
/* For all combinations: +0 < +0, +0 < -0, -0 < +0, -0 < -0,
* steps e, f, and g.
*/
goto lt_false;
}
if (d1 == d2) {
goto lt_false;
}
if (c1 == DUK_FP_INFINITE && s1 == 0) {
/* x == +Infinity */
goto lt_false;
}
if (c2 == DUK_FP_INFINITE && s2 == 0) {
/* y == +Infinity */
goto lt_true;
}
if (c2 == DUK_FP_INFINITE && s2 != 0) {
/* y == -Infinity */
goto lt_false;
}
if (c1 == DUK_FP_INFINITE && s1 != 0) {
/* x == -Infinity */
goto lt_true;
}
if (d1 < d2) {
goto lt_true;
}
goto lt_false;
}
lt_undefined:
/* Note: undefined from Section 11.8.5 always results in false
* return (see e.g. Section 11.8.3) - hence special treatment here.
*/
retval = 0;
goto cleanup;
lt_true:
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval = 0;
goto cleanup;
} else {
retval = 1;
goto cleanup;
}
/* never here */
lt_false:
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval = 1;
goto cleanup;
} else {
retval = 0;
goto cleanup;
}
/* never here */
cleanup:
duk_pop_2(ctx);
return retval;
}
duk_bool_t duk_js_compare_helper(duk_hthread *thr, duk_tval *tv_x, duk_tval *tv_y, duk_small_int_t flags) {
duk_context *ctx = (duk_context *) thr;
duk_double_t d1, d2;
duk_small_int_t c1, c2;
duk_small_int_t s1, s2;
duk_small_int_t rc;
duk_bool_t retval;
duk_push_tval(ctx, tv_x);
duk_push_tval(ctx, tv_y);
if (flags & DUK_COMPARE_FLAG_EVAL_LEFT_FIRST) {
duk_to_primitive(ctx, -2, DUK_HINT_NUMBER);
duk_to_primitive(ctx, -1, DUK_HINT_NUMBER);
} else {
duk_to_primitive(ctx, -1, DUK_HINT_NUMBER);
duk_to_primitive(ctx, -2, DUK_HINT_NUMBER);
}
/* Note: reuse variables */
tv_x = duk_get_tval(ctx, -2);
tv_y = duk_get_tval(ctx, -1);
if (DUK_TVAL_IS_STRING(tv_x) && DUK_TVAL_IS_STRING(tv_y)) {
duk_hstring *h1 = DUK_TVAL_GET_STRING(tv_x);
duk_hstring *h2 = DUK_TVAL_GET_STRING(tv_y);
DUK_ASSERT(h1 != NULL);
DUK_ASSERT(h2 != NULL);
rc = duk_js_string_compare(h1, h2);
if (rc < 0) {
goto lt_true;
} else {
goto lt_false;
}
} else {
/* Ordering should not matter (E5 Section 11.8.5, step 3.a) but
* preserve it just in case.
*/
if (flags & DUK_COMPARE_FLAG_EVAL_LEFT_FIRST) {
d1 = duk_to_number(ctx, -2);
d2 = duk_to_number(ctx, -1);
} else {
d2 = duk_to_number(ctx, -1);
d1 = duk_to_number(ctx, -2);
}
c1 = (duk_small_int_t) DUK_FPCLASSIFY(d1);
s1 = (duk_small_int_t) DUK_SIGNBIT(d1);
c2 = (duk_small_int_t) DUK_FPCLASSIFY(d2);
s2 = (duk_small_int_t) DUK_SIGNBIT(d2);
if (c1 == DUK_FP_NAN || c2 == DUK_FP_NAN) {
goto lt_undefined;
}
if (c1 == DUK_FP_ZERO && c2 == DUK_FP_ZERO) {
/* For all combinations: +0 < +0, +0 < -0, -0 < +0, -0 < -0,
* steps e, f, and g.
*/
goto lt_false;
}
if (d1 == d2) {
goto lt_false;
}
if (c1 == DUK_FP_INFINITE && s1 == 0) {
/* x == +Infinity */
goto lt_false;
}
if (c2 == DUK_FP_INFINITE && s2 == 0) {
/* y == +Infinity */
goto lt_true;
}
if (c2 == DUK_FP_INFINITE && s2 != 0) {
/* y == -Infinity */
goto lt_false;
}
if (c1 == DUK_FP_INFINITE && s1 != 0) {
/* x == -Infinity */
goto lt_true;
}
if (d1 < d2) {
goto lt_true;
}
goto lt_false;
}
lt_undefined:
/* Note: undefined from Section 11.8.5 always results in false
* return (see e.g. Section 11.8.3) - hence special treatment here.
*/
retval = 0;
goto cleanup;
lt_true:
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval = 0;
goto cleanup;
} else {
retval = 1;
goto cleanup;
}
/* never here */
lt_false:
if (flags & DUK_COMPARE_FLAG_NEGATE) {
retval = 1;
goto cleanup;
} else {
retval = 0;
goto cleanup;
}
/* never here */
cleanup:
duk_pop_2(ctx);
return retval;
}