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cosmopolitan/third_party/duktape/duk_bi_array.c

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/*
* Array built-ins
*
* Most Array built-ins are intentionally generic in ECMAScript, and are
* intended to work even when the 'this' binding is not an Array instance.
* This ECMAScript feature is also used by much real world code. For this
* reason the implementations here don't assume exotic Array behavior or
* e.g. presence of a .length property. However, some algorithms have a
* fast path for duk_harray backed actual Array instances, enabled when
* footprint is not a concern.
*
* XXX: the "Throw" flag should be set for (almost?) all [[Put]] and
* [[Delete]] operations, but it's currently false throughout. Go through
* all put/delete cases and check throw flag use. Need a new API primitive
* which allows throws flag to be specified.
*
* XXX: array lengths above 2G won't work reliably. There are many places
* where one needs a full signed 32-bit range ([-0xffffffff, 0xffffffff],
* i.e. -33- bits). Although array 'length' cannot be written to be outside
* the unsigned 32-bit range (E5.1 Section 15.4.5.1 throws a RangeError if so)
* some intermediate values may be above 0xffffffff and this may not be always
* correctly handled now (duk_uint32_t is not enough for all algorithms).
* For instance, push() can legitimately write entries beyond length 0xffffffff
* and cause a RangeError only at the end. To do this properly, the current
* push() implementation tracks the array index using a 'double' instead of a
* duk_uint32_t (which is somewhat awkward). See test-bi-array-push-maxlen.js.
*
* On using "put" vs. "def" prop
* =============================
*
* Code below must be careful to use the appropriate primitive as it matters
* for compliance. When using "put" there may be inherited properties in
* Array.prototype which cause side effects when values are written. When
* using "define" there are no such side effects, and many test262 test cases
* check for this (for real world code, such side effects are very rare).
* Both "put" and "define" are used in the E5.1 specification; as a rule,
* "put" is used when modifying an existing array (or a non-array 'this'
* binding) and "define" for setting values into a fresh result array.
*/
#include "third_party/duktape/duk_internal.h"
/* Perform an intermediate join when this many elements have been pushed
* on the value stack.
*/
#define DUK__ARRAY_MID_JOIN_LIMIT 4096
#if defined(DUK_USE_ARRAY_BUILTIN)
/*
* Shared helpers.
*/
/* Shared entry code for many Array built-ins: the 'this' binding is pushed
* on the value stack and object coerced, and the current .length is returned.
* Note that length is left on stack (it could be popped, but that's not
* usually necessary because call handling will clean it up automatically).
*/
DUK_LOCAL duk_uint32_t duk__push_this_obj_len_u32(duk_hthread *thr) {
duk_uint32_t len;
/* XXX: push more directly? */
(void) duk_push_this_coercible_to_object(thr);
DUK_HOBJECT_ASSERT_VALID(duk_get_hobject(thr, -1));
duk_get_prop_stridx_short(thr, -1, DUK_STRIDX_LENGTH);
len = duk_to_uint32(thr, -1);
/* -> [ ... ToObject(this) ToUint32(length) ] */
return len;
}
DUK_LOCAL duk_uint32_t duk__push_this_obj_len_u32_limited(duk_hthread *thr) {
/* Range limited to [0, 0x7fffffff] range, i.e. range that can be
* represented with duk_int32_t. Use this when the method doesn't
* handle the full 32-bit unsigned range correctly.
*/
duk_uint32_t ret = duk__push_this_obj_len_u32(thr);
if (DUK_UNLIKELY(ret >= 0x80000000UL)) {
DUK_ERROR_RANGE_INVALID_LENGTH(thr);
DUK_WO_NORETURN(return 0U;);
}
return ret;
}
#if defined(DUK_USE_ARRAY_FASTPATH)
/* Check if 'this' binding is an Array instance (duk_harray) which satisfies
* a few other guarantees for fast path operation. The fast path doesn't
* need to handle all operations, even for duk_harrays, but must handle a
* significant fraction to improve performance. Return a non-NULL duk_harray
* pointer when all fast path criteria are met, NULL otherwise.
*/
DUK_LOCAL duk_harray *duk__arraypart_fastpath_this(duk_hthread *thr) {
duk_tval *tv;
duk_hobject *h;
duk_uint_t flags_mask, flags_bits, flags_value;
DUK_ASSERT(thr->valstack_bottom > thr->valstack); /* because call in progress */
tv = DUK_GET_THIS_TVAL_PTR(thr);
/* Fast path requires that 'this' is a duk_harray. Read only arrays
* (ROM backed) are also rejected for simplicity.
*/
if (!DUK_TVAL_IS_OBJECT(tv)) {
DUK_DD(DUK_DDPRINT("reject array fast path: not an object"));
return NULL;
}
h = DUK_TVAL_GET_OBJECT(tv);
DUK_ASSERT(h != NULL);
flags_mask = DUK_HOBJECT_FLAG_ARRAY_PART | \
DUK_HOBJECT_FLAG_EXOTIC_ARRAY | \
DUK_HEAPHDR_FLAG_READONLY;
flags_bits = DUK_HOBJECT_FLAG_ARRAY_PART | \
DUK_HOBJECT_FLAG_EXOTIC_ARRAY;
flags_value = DUK_HEAPHDR_GET_FLAGS_RAW((duk_heaphdr *) h);
if ((flags_value & flags_mask) != flags_bits) {
DUK_DD(DUK_DDPRINT("reject array fast path: object flag check failed"));
return NULL;
}
/* In some cases a duk_harray's 'length' may be larger than the
* current array part allocation. Avoid the fast path in these
* cases, so that all fast path code can safely assume that all
* items in the range [0,length[ are backed by the current array
* part allocation.
*/
if (((duk_harray *) h)->length > DUK_HOBJECT_GET_ASIZE(h)) {
DUK_DD(DUK_DDPRINT("reject array fast path: length > array part size"));
return NULL;
}
/* Guarantees for fast path. */
DUK_ASSERT(h != NULL);
DUK_ASSERT(DUK_HOBJECT_GET_ASIZE(h) == 0 || DUK_HOBJECT_A_GET_BASE(thr->heap, h) != NULL);
DUK_ASSERT(((duk_harray *) h)->length <= DUK_HOBJECT_GET_ASIZE(h));
DUK_DD(DUK_DDPRINT("array fast path allowed for: %!O", (duk_heaphdr *) h));
return (duk_harray *) h;
}
#endif /* DUK_USE_ARRAY_FASTPATH */
/*
* Constructor
*/
DUK_INTERNAL duk_ret_t duk_bi_array_constructor(duk_hthread *thr) {
duk_idx_t nargs;
duk_harray *a;
duk_double_t d;
duk_uint32_t len;
duk_uint32_t len_prealloc;
nargs = duk_get_top(thr);
if (nargs == 1 && duk_is_number(thr, 0)) {
/* XXX: expensive check (also shared elsewhere - so add a shared internal API call?) */
d = duk_get_number(thr, 0);
len = duk_to_uint32(thr, 0);
if (!duk_double_equals((duk_double_t) len, d)) {
DUK_DCERROR_RANGE_INVALID_LENGTH(thr);
}
/* For small lengths create a dense preallocated array.
* For large arrays preallocate an initial part.
*/
len_prealloc = len < 64 ? len : 64;
a = duk_push_harray_with_size(thr, len_prealloc);
DUK_ASSERT(a != NULL);
DUK_ASSERT(!duk_is_bare_object(thr, -1));
a->length = len;
return 1;
}
duk_pack(thr, nargs);
return 1;
}
/*
* isArray()
*/
DUK_INTERNAL duk_ret_t duk_bi_array_constructor_is_array(duk_hthread *thr) {
DUK_ASSERT_TOP(thr, 1);
duk_push_boolean(thr, duk_js_isarray(DUK_GET_TVAL_POSIDX(thr, 0)));
return 1;
}
/*
* toString()
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_to_string(duk_hthread *thr) {
(void) duk_push_this_coercible_to_object(thr);
duk_get_prop_stridx_short(thr, -1, DUK_STRIDX_JOIN);
/* [ ... this func ] */
if (!duk_is_callable(thr, -1)) {
/* Fall back to the initial (original) Object.toString(). We don't
* currently have pointers to the built-in functions, only the top
* level global objects (like "Array") so this is now done in a bit
* of a hacky manner. It would be cleaner to push the (original)
* function and use duk_call_method().
*/
/* XXX: 'this' will be ToObject() coerced twice, which is incorrect
* but should have no visible side effects.
*/
DUK_DDD(DUK_DDDPRINT("this.join is not callable, fall back to (original) Object.toString"));
duk_set_top(thr, 0);
return duk_bi_object_prototype_to_string(thr); /* has access to 'this' binding */
}
/* [ ... this func ] */
duk_insert(thr, -2);
/* [ ... func this ] */
DUK_DDD(DUK_DDDPRINT("calling: func=%!iT, this=%!iT",
(duk_tval *) duk_get_tval(thr, -2),
(duk_tval *) duk_get_tval(thr, -1)));
duk_call_method(thr, 0);
return 1;
}
/*
* concat()
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_concat(duk_hthread *thr) {
duk_idx_t i, n;
duk_uint32_t j, idx, len;
duk_hobject *h;
duk_size_t tmp_len;
/* XXX: In ES2015 Array .length can be up to 2^53-1. The current
* implementation is limited to 2^32-1.
*/
/* XXX: Fast path for array 'this' and array element. */
/* XXX: The insert here is a bit expensive if there are a lot of items.
* It could also be special cased in the outermost for loop quite easily
* (as the element is dup()'d anyway).
*/
(void) duk_push_this_coercible_to_object(thr);
duk_insert(thr, 0);
n = duk_get_top(thr);
duk_push_array(thr); /* -> [ ToObject(this) item1 ... itemN arr ] */
/* NOTE: The Array special behaviors are NOT invoked by duk_xdef_prop_index()
* (which differs from the official algorithm). If no error is thrown, this
* doesn't matter as the length is updated at the end. However, if an error
* is thrown, the length will be unset. That shouldn't matter because the
* caller won't get a reference to the intermediate value.
*/
idx = 0;
for (i = 0; i < n; i++) {
duk_bool_t spreadable;
duk_bool_t need_has_check;
DUK_ASSERT_TOP(thr, n + 1);
/* [ ToObject(this) item1 ... itemN arr ] */
h = duk_get_hobject(thr, i);
if (h == NULL) {
spreadable = 0;
} else {
#if defined(DUK_USE_SYMBOL_BUILTIN)
duk_get_prop_stridx(thr, i, DUK_STRIDX_WELLKNOWN_SYMBOL_IS_CONCAT_SPREADABLE);
if (duk_is_undefined(thr, -1)) {
spreadable = duk_js_isarray_hobject(h);
} else {
spreadable = duk_to_boolean(thr, -1);
}
duk_pop_nodecref_unsafe(thr);
#else
spreadable = duk_js_isarray_hobject(h);
#endif
}
if (!spreadable) {
duk_dup(thr, i);
duk_xdef_prop_index_wec(thr, -2, idx);
idx++;
if (DUK_UNLIKELY(idx == 0U)) {
/* Index after update is 0, and index written
* was 0xffffffffUL which is no longer a valid
* array index.
*/
goto fail_wrap;
}
continue;
}
DUK_ASSERT(duk_is_object(thr, i));
need_has_check = (DUK_HOBJECT_IS_PROXY(h) != 0); /* Always 0 w/o Proxy support. */
/* [ ToObject(this) item1 ... itemN arr ] */
tmp_len = duk_get_length(thr, i);
len = (duk_uint32_t) tmp_len;
if (DUK_UNLIKELY(tmp_len != (duk_size_t) len)) {
goto fail_wrap;
}
if (DUK_UNLIKELY(idx + len < idx)) {
/* Result length must be at most 0xffffffffUL to be
* a valid 32-bit array index.
*/
goto fail_wrap;
}
for (j = 0; j < len; j++) {
/* For a Proxy element, an explicit 'has' check is
* needed to allow the Proxy to present gaps.
*/
if (need_has_check) {
if (duk_has_prop_index(thr, i, j)) {
duk_get_prop_index(thr, i, j);
duk_xdef_prop_index_wec(thr, -2, idx);
}
} else {
if (duk_get_prop_index(thr, i, j)) {
duk_xdef_prop_index_wec(thr, -2, idx);
} else {
duk_pop_undefined(thr);
}
}
idx++;
DUK_ASSERT(idx != 0U); /* Wrap check above. */
}
}
/* ES5.1 has a specification "bug" in that nonexistent trailing
* elements don't affect the result .length. Test262 and other
* engines disagree, and the specification bug was fixed in ES2015
* (see NOTE 1 in https://www.ecma-international.org/ecma-262/6.0/#sec-array.prototype.concat).
*/
duk_push_uarridx(thr, idx);
duk_xdef_prop_stridx_short(thr, -2, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W);
DUK_ASSERT_TOP(thr, n + 1);
return 1;
fail_wrap:
DUK_ERROR_RANGE_INVALID_LENGTH(thr);
DUK_WO_NORETURN(return 0;);
}
/*
* join(), toLocaleString()
*
* Note: checking valstack is necessary, but only in the per-element loop.
*
* Note: the trivial approach of pushing all the elements on the value stack
* and then calling duk_join() fails when the array contains a large number
* of elements. This problem can't be offloaded to duk_join() because the
* elements to join must be handled here and have special handling. Current
* approach is to do intermediate joins with very large number of elements.
* There is no fancy handling; the prefix gets re-joined multiple times.
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_join_shared(duk_hthread *thr) {
duk_uint32_t len, count;
duk_uint32_t idx;
duk_small_int_t to_locale_string = duk_get_current_magic(thr);
duk_idx_t valstack_required;
/* For join(), nargs is 1. For toLocaleString(), nargs is 0 and
* setting the top essentially pushes an undefined to the stack,
* thus defaulting to a comma separator.
*/
duk_set_top(thr, 1);
if (duk_is_undefined(thr, 0)) {
duk_pop_undefined(thr);
duk_push_hstring_stridx(thr, DUK_STRIDX_COMMA);
} else {
duk_to_string(thr, 0);
}
len = duk__push_this_obj_len_u32(thr);
/* [ sep ToObject(this) len ] */
DUK_DDD(DUK_DDDPRINT("sep=%!T, this=%!T, len=%lu",
(duk_tval *) duk_get_tval(thr, 0),
(duk_tval *) duk_get_tval(thr, 1),
(unsigned long) len));
/* The extra (+4) is tight. */
valstack_required = (duk_idx_t) ((len >= DUK__ARRAY_MID_JOIN_LIMIT ?
DUK__ARRAY_MID_JOIN_LIMIT : len) + 4);
duk_require_stack(thr, valstack_required);
duk_dup_0(thr);
/* [ sep ToObject(this) len sep ] */
count = 0;
idx = 0;
for (;;) {
DUK_DDD(DUK_DDDPRINT("join idx=%ld", (long) idx));
if (count >= DUK__ARRAY_MID_JOIN_LIMIT || /* intermediate join to avoid valstack overflow */
idx >= len) { /* end of loop (careful with len==0) */
/* [ sep ToObject(this) len sep str0 ... str(count-1) ] */
DUK_DDD(DUK_DDDPRINT("mid/final join, count=%ld, idx=%ld, len=%ld",
(long) count, (long) idx, (long) len));
duk_join(thr, (duk_idx_t) count); /* -> [ sep ToObject(this) len str ] */
duk_dup_0(thr); /* -> [ sep ToObject(this) len str sep ] */
duk_insert(thr, -2); /* -> [ sep ToObject(this) len sep str ] */
count = 1;
}
if (idx >= len) {
/* if true, the stack already contains the final result */
break;
}
duk_get_prop_index(thr, 1, (duk_uarridx_t) idx);
if (duk_is_null_or_undefined(thr, -1)) {
duk_pop_nodecref_unsafe(thr);
duk_push_hstring_empty(thr);
} else {
if (to_locale_string) {
duk_to_object(thr, -1);
duk_get_prop_stridx_short(thr, -1, DUK_STRIDX_TO_LOCALE_STRING);
duk_insert(thr, -2); /* -> [ ... toLocaleString ToObject(val) ] */
duk_call_method(thr, 0);
}
duk_to_string(thr, -1);
}
count++;
idx++;
}
/* [ sep ToObject(this) len sep result ] */
return 1;
}
/*
* pop(), push()
*/
#if defined(DUK_USE_ARRAY_FASTPATH)
DUK_LOCAL duk_ret_t duk__array_pop_fastpath(duk_hthread *thr, duk_harray *h_arr) {
duk_tval *tv_arraypart;
duk_tval *tv_val;
duk_uint32_t len;
tv_arraypart = DUK_HOBJECT_A_GET_BASE(thr->heap, (duk_hobject *) h_arr);
len = h_arr->length;
if (len <= 0) {
/* nop, return undefined */
return 0;
}
len--;
h_arr->length = len;
/* Fast path doesn't check for an index property inherited from
* Array.prototype. This is quite often acceptable; if not,
* disable fast path.
*/
DUK_ASSERT_VS_SPACE(thr);
tv_val = tv_arraypart + len;
if (DUK_TVAL_IS_UNUSED(tv_val)) {
/* No net refcount change. Value stack already has
* 'undefined' based on value stack init policy.
*/
DUK_ASSERT(DUK_TVAL_IS_UNDEFINED(thr->valstack_top));
DUK_ASSERT(DUK_TVAL_IS_UNUSED(tv_val));
} else {
/* No net refcount change. */
DUK_TVAL_SET_TVAL(thr->valstack_top, tv_val);
DUK_TVAL_SET_UNUSED(tv_val);
}
thr->valstack_top++;
/* XXX: there's no shrink check in the fast path now */
return 1;
}
#endif /* DUK_USE_ARRAY_FASTPATH */
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_pop(duk_hthread *thr) {
duk_uint32_t len;
duk_uint32_t idx;
#if defined(DUK_USE_ARRAY_FASTPATH)
duk_harray *h_arr;
#endif
DUK_ASSERT_TOP(thr, 0);
#if defined(DUK_USE_ARRAY_FASTPATH)
h_arr = duk__arraypart_fastpath_this(thr);
if (h_arr) {
return duk__array_pop_fastpath(thr, h_arr);
}
#endif
/* XXX: Merge fastpath check into a related call (push this, coerce length, etc)? */
len = duk__push_this_obj_len_u32(thr);
if (len == 0) {
duk_push_int(thr, 0);
duk_put_prop_stridx_short(thr, 0, DUK_STRIDX_LENGTH);
return 0;
}
idx = len - 1;
duk_get_prop_index(thr, 0, (duk_uarridx_t) idx);
duk_del_prop_index(thr, 0, (duk_uarridx_t) idx);
duk_push_u32(thr, idx);
duk_put_prop_stridx_short(thr, 0, DUK_STRIDX_LENGTH);
return 1;
}
#if defined(DUK_USE_ARRAY_FASTPATH)
DUK_LOCAL duk_ret_t duk__array_push_fastpath(duk_hthread *thr, duk_harray *h_arr) {
duk_tval *tv_arraypart;
duk_tval *tv_src;
duk_tval *tv_dst;
duk_uint32_t len;
duk_idx_t i, n;
len = h_arr->length;
tv_arraypart = DUK_HOBJECT_A_GET_BASE(thr->heap, (duk_hobject *) h_arr);
n = (duk_idx_t) (thr->valstack_top - thr->valstack_bottom);
DUK_ASSERT(n >= 0);
DUK_ASSERT((duk_uint32_t) n <= DUK_UINT32_MAX);
if (DUK_UNLIKELY(len + (duk_uint32_t) n < len)) {
DUK_D(DUK_DPRINT("Array.prototype.push() would go beyond 32-bit length, throw"));
DUK_DCERROR_RANGE_INVALID_LENGTH(thr); /* != 0 return value returned as is by caller */
}
if (len + (duk_uint32_t) n > DUK_HOBJECT_GET_ASIZE((duk_hobject *) h_arr)) {
/* Array part would need to be extended. Rely on slow path
* for now.
*
* XXX: Rework hobject code a bit and add extend support.
*/
return 0;
}
tv_src = thr->valstack_bottom;
tv_dst = tv_arraypart + len;
for (i = 0; i < n; i++) {
/* No net refcount change; reset value stack values to
* undefined to satisfy value stack init policy.
*/
DUK_TVAL_SET_TVAL(tv_dst, tv_src);
DUK_TVAL_SET_UNDEFINED(tv_src);
tv_src++;
tv_dst++;
}
thr->valstack_top = thr->valstack_bottom;
len += (duk_uint32_t) n;
h_arr->length = len;
DUK_ASSERT((duk_uint_t) len == len);
duk_push_uint(thr, (duk_uint_t) len);
return 1;
}
#endif /* DUK_USE_ARRAY_FASTPATH */
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_push(duk_hthread *thr) {
/* Note: 'this' is not necessarily an Array object. The push()
* algorithm is supposed to work for other kinds of objects too,
* so the algorithm has e.g. an explicit update for the 'length'
* property which is normally "magical" in arrays.
*/
duk_uint32_t len;
duk_idx_t i, n;
#if defined(DUK_USE_ARRAY_FASTPATH)
duk_harray *h_arr;
#endif
#if defined(DUK_USE_ARRAY_FASTPATH)
h_arr = duk__arraypart_fastpath_this(thr);
if (h_arr) {
duk_ret_t rc;
rc = duk__array_push_fastpath(thr, h_arr);
if (rc != 0) {
return rc;
}
DUK_DD(DUK_DDPRINT("array push() fast path exited, resize case"));
}
#endif
n = duk_get_top(thr);
len = duk__push_this_obj_len_u32(thr);
/* [ arg1 ... argN obj length ] */
/* Technically Array.prototype.push() can create an Array with length
* longer than 2^32-1, i.e. outside the 32-bit range. The final length
* is *not* wrapped to 32 bits in the specification.
*
* This implementation tracks length with a uint32 because it's much
* more practical.
*
* See: test-bi-array-push-maxlen.js.
*/
if (len + (duk_uint32_t) n < len) {
DUK_D(DUK_DPRINT("Array.prototype.push() would go beyond 32-bit length, throw"));
DUK_DCERROR_RANGE_INVALID_LENGTH(thr);
}
for (i = 0; i < n; i++) {
duk_dup(thr, i);
duk_put_prop_index(thr, -3, (duk_uarridx_t) (len + (duk_uint32_t) i));
}
len += (duk_uint32_t) n;
duk_push_u32(thr, len);
duk_dup_top(thr);
duk_put_prop_stridx_short(thr, -4, DUK_STRIDX_LENGTH);
/* [ arg1 ... argN obj length new_length ] */
return 1;
}
/*
* sort()
*
* Currently qsort with random pivot. This is now really, really slow,
* because there is no fast path for array parts.
*
* Signed indices are used because qsort() leaves and degenerate cases
* may use a negative offset.
*/
DUK_LOCAL duk_small_int_t duk__array_sort_compare(duk_hthread *thr, 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(thr, idx_obj, (duk_uarridx_t) idx1);
have2 = duk_get_prop_index(thr, 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(thr, -2), (duk_tval *) duk_get_tval(thr, -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(thr, -2);
undef2 = duk_is_undefined(thr, -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(thr, idx_fn)) {
duk_double_t d;
/* No need to check callable; duk_call() will do that. */
duk_dup(thr, idx_fn); /* -> [ ... x y fn ] */
duk_insert(thr, -3); /* -> [ ... fn x y ] */
duk_call(thr, 2); /* -> [ ... res ] */
/* ES5 is a bit vague about what to do if the return value is
* not a number. ES2015 provides a concrete description:
* http://www.ecma-international.org/ecma-262/6.0/#sec-sortcompare.
*/
d = duk_to_number_m1(thr);
if (d < 0.0) {
ret = -1;
} else if (d > 0.0) {
ret = 1;
} else {
/* Because NaN compares to false, NaN is handled here
* without an explicit check above.
*/
ret = 0;
}
duk_pop_nodecref_unsafe(thr);
DUK_DDD(DUK_DDDPRINT("-> result %ld (from comparefn, after coercion)", (long) ret));
return ret;
}
/* string compare is the default (a bit oddly) */
/* XXX: any special handling for plain array; causes repeated coercion now? */
h1 = duk_to_hstring(thr, -2);
h2 = duk_to_hstring_m1(thr);
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_unsafe(thr);
DUK_DDD(DUK_DDDPRINT("-> result %ld", (long) ret));
return ret;
}
DUK_LOCAL void duk__array_sort_swap(duk_hthread *thr, duk_int_t l, duk_int_t r) {
duk_bool_t have_l, have_r;
duk_idx_t idx_obj = 1; /* fixed offset in valstack */
if (l == r) {
return;
}
/* swap elements; deal with non-existent elements correctly */
have_l = duk_get_prop_index(thr, idx_obj, (duk_uarridx_t) l);
have_r = duk_get_prop_index(thr, idx_obj, (duk_uarridx_t) r);
if (have_r) {
/* right exists, [[Put]] regardless whether or not left exists */
duk_put_prop_index(thr, idx_obj, (duk_uarridx_t) l);
} else {
duk_del_prop_index(thr, idx_obj, (duk_uarridx_t) l);
duk_pop_undefined(thr);
}
if (have_l) {
duk_put_prop_index(thr, idx_obj, (duk_uarridx_t) r);
} else {
duk_del_prop_index(thr, idx_obj, (duk_uarridx_t) r);
duk_pop_undefined(thr);
}
}
#if defined(DUK_USE_DEBUG_LEVEL) && (DUK_USE_DEBUG_LEVEL >= 2)
/* Debug print which visualizes the qsort partitioning process. */
DUK_LOCAL void duk__debuglog_qsort_state(duk_hthread *thr, duk_int_t lo, duk_int_t hi, duk_int_t pivot) {
char buf[4096];
char *ptr = buf;
duk_int_t i, n;
n = (duk_int_t) duk_get_length(thr, 1);
if (n > 4000) {
n = 4000;
}
*ptr++ = '[';
for (i = 0; i < n; i++) {
if (i == pivot) {
*ptr++ = '|';
} else if (i == lo) {
*ptr++ = '<';
} else if (i == hi) {
*ptr++ = '>';
} else if (i >= lo && i <= hi) {
*ptr++ = '-';
} else {
*ptr++ = ' ';
}
}
*ptr++ = ']';
*ptr++ = '\0';
DUK_DDD(DUK_DDDPRINT("%s (lo=%ld, hi=%ld, pivot=%ld)",
(const char *) buf, (long) lo, (long) hi, (long) pivot));
}
#endif
DUK_LOCAL void duk__array_qsort(duk_hthread *thr, duk_int_t lo, duk_int_t hi) {
duk_int_t p, l, r;
/* The lo/hi indices may be crossed and hi < 0 is possible at entry. */
DUK_DDD(DUK_DDDPRINT("duk__array_qsort: lo=%ld, hi=%ld, obj=%!T",
(long) lo, (long) hi, (duk_tval *) duk_get_tval(thr, 1)));
DUK_ASSERT_TOP(thr, 3);
/* In some cases it may be that lo > hi, or hi < 0; these
* degenerate cases happen e.g. for empty arrays, and in
* recursion leaves.
*/
/* trivial cases */
if (hi - lo < 1) {
DUK_DDD(DUK_DDDPRINT("degenerate case, return immediately"));
return;
}
DUK_ASSERT(hi > lo);
DUK_ASSERT(hi - lo + 1 >= 2);
/* randomized pivot selection */
p = lo + (duk_int_t) (DUK_UTIL_GET_RANDOM_DOUBLE(thr) * (duk_double_t) (hi - lo + 1));
DUK_ASSERT(p >= lo && p <= hi);
DUK_DDD(DUK_DDDPRINT("lo=%ld, hi=%ld, chose pivot p=%ld", (long) lo, (long) hi, (long) p));
/* move pivot out of the way */
duk__array_sort_swap(thr, p, lo);
p = lo;
DUK_DDD(DUK_DDDPRINT("pivot moved out of the way: %!T", (duk_tval *) duk_get_tval(thr, 1)));
l = lo + 1;
r = hi;
for (;;) {
/* find elements to swap */
for (;;) {
DUK_DDD(DUK_DDDPRINT("left scan: l=%ld, r=%ld, p=%ld",
(long) l, (long) r, (long) p));
if (l >= hi) {
break;
}
if (duk__array_sort_compare(thr, l, p) >= 0) { /* !(l < p) */
break;
}
l++;
}
for (;;) {
DUK_DDD(DUK_DDDPRINT("right scan: l=%ld, r=%ld, p=%ld",
(long) l, (long) r, (long) p));
if (r <= lo) {
break;
}
if (duk__array_sort_compare(thr, p, r) >= 0) { /* !(p < r) */
break;
}
r--;
}
if (l >= r) {
goto done;
}
DUK_ASSERT(l < r);
DUK_DDD(DUK_DDDPRINT("swap %ld and %ld", (long) l, (long) r));
duk__array_sort_swap(thr, l, r);
DUK_DDD(DUK_DDDPRINT("after swap: %!T", (duk_tval *) duk_get_tval(thr, 1)));
l++;
r--;
}
done:
/* Note that 'l' and 'r' may cross, i.e. r < l */
DUK_ASSERT(l >= lo && l <= hi);
DUK_ASSERT(r >= lo && r <= hi);
/* XXX: there's no explicit recursion bound here now. For the average
* qsort recursion depth O(log n) that's not really necessary: e.g. for
* 2**32 recursion depth would be about 32 which is OK. However, qsort
* worst case recursion depth is O(n) which may be a problem.
*/
/* move pivot to its final place */
DUK_DDD(DUK_DDDPRINT("before final pivot swap: %!T", (duk_tval *) duk_get_tval(thr, 1)));
duk__array_sort_swap(thr, lo, r);
#if defined(DUK_USE_DEBUG_LEVEL) && (DUK_USE_DEBUG_LEVEL >= 2)
duk__debuglog_qsort_state(thr, lo, hi, r);
#endif
DUK_DDD(DUK_DDDPRINT("recurse: pivot=%ld, obj=%!T", (long) r, (duk_tval *) duk_get_tval(thr, 1)));
duk__array_qsort(thr, lo, r - 1);
duk__array_qsort(thr, r + 1, hi);
}
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_sort(duk_hthread *thr) {
duk_uint32_t len;
/* XXX: len >= 0x80000000 won't work below because a signed type
* is needed by qsort.
*/
len = duk__push_this_obj_len_u32_limited(thr);
/* stack[0] = compareFn
* stack[1] = ToObject(this)
* stack[2] = ToUint32(length)
*/
if (len > 0) {
/* avoid degenerate cases, so that (len - 1) won't underflow */
duk__array_qsort(thr, (duk_int_t) 0, (duk_int_t) (len - 1));
}
DUK_ASSERT_TOP(thr, 3);
duk_pop_nodecref_unsafe(thr);
return 1; /* return ToObject(this) */
}
/*
* splice()
*/
/* XXX: this compiles to over 500 bytes now, even without special handling
* for an array part. Uses signed ints so does not handle full array range correctly.
*/
/* XXX: can shift() / unshift() use the same helper?
* shift() is (close to?) <--> splice(0, 1)
* unshift is (close to?) <--> splice(0, 0, [items])?
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_splice(duk_hthread *thr) {
duk_idx_t nargs;
duk_uint32_t len_u32;
duk_int_t len;
duk_bool_t have_delcount;
duk_int_t item_count;
duk_int_t act_start;
duk_int_t del_count;
duk_int_t i, n;
DUK_UNREF(have_delcount);
nargs = duk_get_top(thr);
if (nargs < 2) {
duk_set_top(thr, 2);
nargs = 2;
have_delcount = 0;
} else {
have_delcount = 1;
}
/* XXX: len >= 0x80000000 won't work below because we need to be
* able to represent -len.
*/
len_u32 = duk__push_this_obj_len_u32_limited(thr);
len = (duk_int_t) len_u32;
DUK_ASSERT(len >= 0);
act_start = duk_to_int_clamped(thr, 0, -len, len);
if (act_start < 0) {
act_start = len + act_start;
}
DUK_ASSERT(act_start >= 0 && act_start <= len);
#if defined(DUK_USE_NONSTD_ARRAY_SPLICE_DELCOUNT)
if (have_delcount) {
#endif
del_count = duk_to_int_clamped(thr, 1, 0, len - act_start);
#if defined(DUK_USE_NONSTD_ARRAY_SPLICE_DELCOUNT)
} else {
/* E5.1 standard behavior when deleteCount is not given would be
* to treat it just like if 'undefined' was given, which coerces
* ultimately to 0. Real world behavior is to splice to the end
* of array, see test-bi-array-proto-splice-no-delcount.js.
*/
del_count = len - act_start;
}
#endif
DUK_ASSERT(nargs >= 2);
item_count = (duk_int_t) (nargs - 2);
DUK_ASSERT(del_count >= 0 && del_count <= len - act_start);
DUK_ASSERT(del_count + act_start <= len);
/* For now, restrict result array into 32-bit length range. */
if (((duk_double_t) len) - ((duk_double_t) del_count) + ((duk_double_t) item_count) > (duk_double_t) DUK_UINT32_MAX) {
DUK_D(DUK_DPRINT("Array.prototype.splice() would go beyond 32-bit length, throw"));
DUK_DCERROR_RANGE_INVALID_LENGTH(thr);
}
duk_push_array(thr);
/* stack[0] = start
* stack[1] = deleteCount
* stack[2...nargs-1] = items
* stack[nargs] = ToObject(this) -3
* stack[nargs+1] = ToUint32(length) -2
* stack[nargs+2] = result array -1
*/
DUK_ASSERT_TOP(thr, nargs + 3);
/* Step 9: copy elements-to-be-deleted into the result array */
for (i = 0; i < del_count; i++) {
if (duk_get_prop_index(thr, -3, (duk_uarridx_t) (act_start + i))) {
duk_xdef_prop_index_wec(thr, -2, (duk_uarridx_t) i); /* throw flag irrelevant (false in std alg) */
} else {
duk_pop_undefined(thr);
}
}
duk_push_u32(thr, (duk_uint32_t) del_count);
duk_xdef_prop_stridx_short(thr, -2, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W);
/* Steps 12 and 13: reorganize elements to make room for itemCount elements */
if (item_count < del_count) {
/* [ A B C D E F G H ] rel_index = 2, del_count 3, item count 1
* -> [ A B F G H ] (conceptual intermediate step)
* -> [ A B . F G H ] (placeholder marked)
* [ A B C F G H ] (actual result at this point, C will be replaced)
*/
DUK_ASSERT_TOP(thr, nargs + 3);
n = len - del_count;
for (i = act_start; i < n; i++) {
if (duk_get_prop_index(thr, -3, (duk_uarridx_t) (i + del_count))) {
duk_put_prop_index(thr, -4, (duk_uarridx_t) (i + item_count));
} else {
duk_pop_undefined(thr);
duk_del_prop_index(thr, -3, (duk_uarridx_t) (i + item_count));
}
}
DUK_ASSERT_TOP(thr, nargs + 3);
/* loop iterator init and limit changed from standard algorithm */
n = len - del_count + item_count;
for (i = len - 1; i >= n; i--) {
duk_del_prop_index(thr, -3, (duk_uarridx_t) i);
}
DUK_ASSERT_TOP(thr, nargs + 3);
} else if (item_count > del_count) {
/* [ A B C D E F G H ] rel_index = 2, del_count 3, item count 4
* -> [ A B F G H ] (conceptual intermediate step)
* -> [ A B . . . . F G H ] (placeholder marked)
* [ A B C D E F F G H ] (actual result at this point)
*/
DUK_ASSERT_TOP(thr, nargs + 3);
/* loop iterator init and limit changed from standard algorithm */
for (i = len - del_count - 1; i >= act_start; i--) {
if (duk_get_prop_index(thr, -3, (duk_uarridx_t) (i + del_count))) {
duk_put_prop_index(thr, -4, (duk_uarridx_t) (i + item_count));
} else {
duk_pop_undefined(thr);
duk_del_prop_index(thr, -3, (duk_uarridx_t) (i + item_count));
}
}
DUK_ASSERT_TOP(thr, nargs + 3);
} else {
/* [ A B C D E F G H ] rel_index = 2, del_count 3, item count 3
* -> [ A B F G H ] (conceptual intermediate step)
* -> [ A B . . . F G H ] (placeholder marked)
* [ A B C D E F G H ] (actual result at this point)
*/
}
DUK_ASSERT_TOP(thr, nargs + 3);
/* Step 15: insert itemCount elements into the hole made above */
for (i = 0; i < item_count; i++) {
duk_dup(thr, i + 2); /* args start at index 2 */
duk_put_prop_index(thr, -4, (duk_uarridx_t) (act_start + i));
}
/* Step 16: update length; note that the final length may be above 32 bit range
* (but we checked above that this isn't the case here)
*/
duk_push_u32(thr, (duk_uint32_t) (len - del_count + item_count));
duk_put_prop_stridx_short(thr, -4, DUK_STRIDX_LENGTH);
/* result array is already at the top of stack */
DUK_ASSERT_TOP(thr, nargs + 3);
return 1;
}
/*
* reverse()
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_reverse(duk_hthread *thr) {
duk_uint32_t len;
duk_uint32_t middle;
duk_uint32_t lower, upper;
duk_bool_t have_lower, have_upper;
len = duk__push_this_obj_len_u32(thr);
middle = len / 2;
/* If len <= 1, middle will be 0 and for-loop bails out
* immediately (0 < 0 -> false).
*/
for (lower = 0; lower < middle; lower++) {
DUK_ASSERT(len >= 2);
DUK_ASSERT_TOP(thr, 2);
DUK_ASSERT(len >= lower + 1);
upper = len - lower - 1;
have_lower = duk_get_prop_index(thr, -2, (duk_uarridx_t) lower);
have_upper = duk_get_prop_index(thr, -3, (duk_uarridx_t) upper);
/* [ ToObject(this) ToUint32(length) lowerValue upperValue ] */
if (have_upper) {
duk_put_prop_index(thr, -4, (duk_uarridx_t) lower);
} else {
duk_del_prop_index(thr, -4, (duk_uarridx_t) lower);
duk_pop_undefined(thr);
}
if (have_lower) {
duk_put_prop_index(thr, -3, (duk_uarridx_t) upper);
} else {
duk_del_prop_index(thr, -3, (duk_uarridx_t) upper);
duk_pop_undefined(thr);
}
DUK_ASSERT_TOP(thr, 2);
}
DUK_ASSERT_TOP(thr, 2);
duk_pop_unsafe(thr); /* -> [ ToObject(this) ] */
return 1;
}
/*
* slice()
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_slice(duk_hthread *thr) {
duk_uint32_t len_u32;
duk_int_t len;
duk_int_t start, end;
duk_int_t i;
duk_uarridx_t idx;
duk_uint32_t res_length = 0;
/* XXX: len >= 0x80000000 won't work below because we need to be
* able to represent -len.
*/
len_u32 = duk__push_this_obj_len_u32_limited(thr);
len = (duk_int_t) len_u32;
DUK_ASSERT(len >= 0);
duk_push_array(thr);
/* stack[0] = start
* stack[1] = end
* stack[2] = ToObject(this)
* stack[3] = ToUint32(length)
* stack[4] = result array
*/
start = duk_to_int_clamped(thr, 0, -len, len);
if (start < 0) {
start = len + start;
}
/* XXX: could duk_is_undefined() provide defaulting undefined to 'len'
* (the upper limit)?
*/
if (duk_is_undefined(thr, 1)) {
end = len;
} else {
end = duk_to_int_clamped(thr, 1, -len, len);
if (end < 0) {
end = len + end;
}
}
DUK_ASSERT(start >= 0 && start <= len);
DUK_ASSERT(end >= 0 && end <= len);
idx = 0;
for (i = start; i < end; i++) {
DUK_ASSERT_TOP(thr, 5);
if (duk_get_prop_index(thr, 2, (duk_uarridx_t) i)) {
duk_xdef_prop_index_wec(thr, 4, idx);
res_length = idx + 1;
} else {
duk_pop_undefined(thr);
}
idx++;
DUK_ASSERT_TOP(thr, 5);
}
duk_push_u32(thr, res_length);
duk_xdef_prop_stridx_short(thr, 4, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W);
DUK_ASSERT_TOP(thr, 5);
return 1;
}
/*
* shift()
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_shift(duk_hthread *thr) {
duk_uint32_t len;
duk_uint32_t i;
len = duk__push_this_obj_len_u32(thr);
if (len == 0) {
duk_push_int(thr, 0);
duk_put_prop_stridx_short(thr, 0, DUK_STRIDX_LENGTH);
return 0;
}
duk_get_prop_index(thr, 0, 0);
/* stack[0] = object (this)
* stack[1] = ToUint32(length)
* stack[2] = elem at index 0 (retval)
*/
for (i = 1; i < len; i++) {
DUK_ASSERT_TOP(thr, 3);
if (duk_get_prop_index(thr, 0, (duk_uarridx_t) i)) {
/* fromPresent = true */
duk_put_prop_index(thr, 0, (duk_uarridx_t) (i - 1));
} else {
/* fromPresent = false */
duk_del_prop_index(thr, 0, (duk_uarridx_t) (i - 1));
duk_pop_undefined(thr);
}
}
duk_del_prop_index(thr, 0, (duk_uarridx_t) (len - 1));
duk_push_u32(thr, (duk_uint32_t) (len - 1));
duk_put_prop_stridx_short(thr, 0, DUK_STRIDX_LENGTH);
DUK_ASSERT_TOP(thr, 3);
return 1;
}
/*
* unshift()
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_unshift(duk_hthread *thr) {
duk_idx_t nargs;
duk_uint32_t len;
duk_uint32_t i;
nargs = duk_get_top(thr);
len = duk__push_this_obj_len_u32(thr);
/* stack[0...nargs-1] = unshift args (vararg)
* stack[nargs] = ToObject(this)
* stack[nargs+1] = ToUint32(length)
*/
DUK_ASSERT_TOP(thr, nargs + 2);
/* Note: unshift() may operate on indices above unsigned 32-bit range
* and the final length may be >= 2**32. However, we restrict the
* final result to 32-bit range for practicality.
*/
if (len + (duk_uint32_t) nargs < len) {
DUK_D(DUK_DPRINT("Array.prototype.unshift() would go beyond 32-bit length, throw"));
DUK_DCERROR_RANGE_INVALID_LENGTH(thr);
}
i = len;
while (i > 0) {
DUK_ASSERT_TOP(thr, nargs + 2);
i--;
/* k+argCount-1; note that may be above 32-bit range */
if (duk_get_prop_index(thr, -2, (duk_uarridx_t) i)) {
/* fromPresent = true */
/* [ ... ToObject(this) ToUint32(length) val ] */
duk_put_prop_index(thr, -3, (duk_uarridx_t) (i + (duk_uint32_t) nargs)); /* -> [ ... ToObject(this) ToUint32(length) ] */
} else {
/* fromPresent = false */
/* [ ... ToObject(this) ToUint32(length) val ] */
duk_pop_undefined(thr);
duk_del_prop_index(thr, -2, (duk_uarridx_t) (i + (duk_uint32_t) nargs)); /* -> [ ... ToObject(this) ToUint32(length) ] */
}
DUK_ASSERT_TOP(thr, nargs + 2);
}
for (i = 0; i < (duk_uint32_t) nargs; i++) {
DUK_ASSERT_TOP(thr, nargs + 2);
duk_dup(thr, (duk_idx_t) i); /* -> [ ... ToObject(this) ToUint32(length) arg[i] ] */
duk_put_prop_index(thr, -3, (duk_uarridx_t) i);
DUK_ASSERT_TOP(thr, nargs + 2);
}
DUK_ASSERT_TOP(thr, nargs + 2);
duk_push_u32(thr, len + (duk_uint32_t) nargs);
duk_dup_top(thr); /* -> [ ... ToObject(this) ToUint32(length) final_len final_len ] */
duk_put_prop_stridx_short(thr, -4, DUK_STRIDX_LENGTH);
return 1;
}
/*
* indexOf(), lastIndexOf()
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_indexof_shared(duk_hthread *thr) {
duk_idx_t nargs;
duk_int_t i, len;
duk_int_t from_idx;
duk_small_int_t idx_step = duk_get_current_magic(thr); /* idx_step is +1 for indexOf, -1 for lastIndexOf */
/* lastIndexOf() needs to be a vararg function because we must distinguish
* between an undefined fromIndex and a "not given" fromIndex; indexOf() is
* made vararg for symmetry although it doesn't strictly need to be.
*/
nargs = duk_get_top(thr);
duk_set_top(thr, 2);
/* XXX: must be able to represent -len */
len = (duk_int_t) duk__push_this_obj_len_u32_limited(thr);
if (len == 0) {
goto not_found;
}
/* Index clamping is a bit tricky, we must ensure that we'll only iterate
* through elements that exist and that the specific requirements from E5.1
* Sections 15.4.4.14 and 15.4.4.15 are fulfilled; especially:
*
* - indexOf: clamp to [-len,len], negative handling -> [0,len],
* if clamped result is len, for-loop bails out immediately
*
* - lastIndexOf: clamp to [-len-1, len-1], negative handling -> [-1, len-1],
* if clamped result is -1, for-loop bails out immediately
*
* If fromIndex is not given, ToInteger(undefined) = 0, which is correct
* for indexOf() but incorrect for lastIndexOf(). Hence special handling,
* and why lastIndexOf() needs to be a vararg function.
*/
if (nargs >= 2) {
/* indexOf: clamp fromIndex to [-len, len]
* (if fromIndex == len, for-loop terminates directly)
*
* lastIndexOf: clamp fromIndex to [-len - 1, len - 1]
* (if clamped to -len-1 -> fromIndex becomes -1, terminates for-loop directly)
*/
from_idx = duk_to_int_clamped(thr,
1,
(idx_step > 0 ? -len : -len - 1),
(idx_step > 0 ? len : len - 1));
if (from_idx < 0) {
/* for lastIndexOf, result may be -1 (mark immediate termination) */
from_idx = len + from_idx;
}
} else {
/* for indexOf, ToInteger(undefined) would be 0, i.e. correct, but
* handle both indexOf and lastIndexOf specially here.
*/
if (idx_step > 0) {
from_idx = 0;
} else {
from_idx = len - 1;
}
}
/* stack[0] = searchElement
* stack[1] = fromIndex
* stack[2] = object
* stack[3] = length (not needed, but not popped above)
*/
for (i = from_idx; i >= 0 && i < len; i += idx_step) {
DUK_ASSERT_TOP(thr, 4);
if (duk_get_prop_index(thr, 2, (duk_uarridx_t) i)) {
DUK_ASSERT_TOP(thr, 5);
if (duk_strict_equals(thr, 0, 4)) {
duk_push_int(thr, i);
return 1;
}
}
duk_pop_unsafe(thr);
}
not_found:
duk_push_int(thr, -1);
return 1;
}
/*
* every(), some(), forEach(), map(), filter()
*/
#define DUK__ITER_EVERY 0
#define DUK__ITER_SOME 1
#define DUK__ITER_FOREACH 2
#define DUK__ITER_MAP 3
#define DUK__ITER_FILTER 4
/* XXX: This helper is a bit awkward because the handling for the different iteration
* callers is quite different. This now compiles to a bit less than 500 bytes, so with
* 5 callers the net result is about 100 bytes / caller.
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_iter_shared(duk_hthread *thr) {
duk_uint32_t len;
duk_uint32_t i;
duk_uarridx_t k;
duk_bool_t bval;
duk_small_int_t iter_type = duk_get_current_magic(thr);
duk_uint32_t res_length = 0;
/* each call this helper serves has nargs==2 */
DUK_ASSERT_TOP(thr, 2);
len = duk__push_this_obj_len_u32(thr);
duk_require_callable(thr, 0);
/* if thisArg not supplied, behave as if undefined was supplied */
if (iter_type == DUK__ITER_MAP || iter_type == DUK__ITER_FILTER) {
duk_push_array(thr);
} else {
duk_push_undefined(thr);
}
/* stack[0] = callback
* stack[1] = thisArg
* stack[2] = object
* stack[3] = ToUint32(length) (unused, but avoid unnecessary pop)
* stack[4] = result array (or undefined)
*/
k = 0; /* result index for filter() */
for (i = 0; i < len; i++) {
DUK_ASSERT_TOP(thr, 5);
if (!duk_get_prop_index(thr, 2, (duk_uarridx_t) i)) {
/* For 'map' trailing missing elements don't invoke the
* callback but count towards the result length.
*/
if (iter_type == DUK__ITER_MAP) {
res_length = i + 1;
}
duk_pop_undefined(thr);
continue;
}
/* The original value needs to be preserved for filter(), hence
* this funny order. We can't re-get the value because of side
* effects.
*/
duk_dup_0(thr);
duk_dup_1(thr);
duk_dup_m3(thr);
duk_push_u32(thr, i);
duk_dup_2(thr); /* [ ... val callback thisArg val i obj ] */
duk_call_method(thr, 3); /* -> [ ... val retval ] */
switch (iter_type) {
case DUK__ITER_EVERY:
bval = duk_to_boolean(thr, -1);
if (!bval) {
/* stack top contains 'false' */
return 1;
}
break;
case DUK__ITER_SOME:
bval = duk_to_boolean(thr, -1);
if (bval) {
/* stack top contains 'true' */
return 1;
}
break;
case DUK__ITER_FOREACH:
/* nop */
break;
case DUK__ITER_MAP:
duk_dup_top(thr);
duk_xdef_prop_index_wec(thr, 4, (duk_uarridx_t) i); /* retval to result[i] */
res_length = i + 1;
break;
case DUK__ITER_FILTER:
bval = duk_to_boolean(thr, -1);
if (bval) {
duk_dup_m2(thr); /* orig value */
duk_xdef_prop_index_wec(thr, 4, (duk_uarridx_t) k);
k++;
res_length = k;
}
break;
default:
DUK_UNREACHABLE();
break;
}
duk_pop_2_unsafe(thr);
DUK_ASSERT_TOP(thr, 5);
}
switch (iter_type) {
case DUK__ITER_EVERY:
duk_push_true(thr);
break;
case DUK__ITER_SOME:
duk_push_false(thr);
break;
case DUK__ITER_FOREACH:
duk_push_undefined(thr);
break;
case DUK__ITER_MAP:
case DUK__ITER_FILTER:
DUK_ASSERT_TOP(thr, 5);
DUK_ASSERT(duk_is_array(thr, -1)); /* topmost element is the result array already */
duk_push_u32(thr, res_length);
duk_xdef_prop_stridx_short(thr, -2, DUK_STRIDX_LENGTH, DUK_PROPDESC_FLAGS_W);
break;
default:
DUK_UNREACHABLE();
break;
}
return 1;
}
/*
* reduce(), reduceRight()
*/
DUK_INTERNAL duk_ret_t duk_bi_array_prototype_reduce_shared(duk_hthread *thr) {
duk_idx_t nargs;
duk_bool_t have_acc;
duk_uint32_t i, len;
duk_small_int_t idx_step = duk_get_current_magic(thr); /* idx_step is +1 for reduce, -1 for reduceRight */
/* We're a varargs function because we need to detect whether
* initialValue was given or not.
*/
nargs = duk_get_top(thr);
DUK_DDD(DUK_DDDPRINT("nargs=%ld", (long) nargs));
duk_set_top(thr, 2);
len = duk__push_this_obj_len_u32(thr);
duk_require_callable(thr, 0);
/* stack[0] = callback fn
* stack[1] = initialValue
* stack[2] = object (coerced this)
* stack[3] = length (not needed, but not popped above)
* stack[4] = accumulator
*/
have_acc = 0;
if (nargs >= 2) {
duk_dup_1(thr);
have_acc = 1;
}
DUK_DDD(DUK_DDDPRINT("have_acc=%ld, acc=%!T",
(long) have_acc, (duk_tval *) duk_get_tval(thr, 3)));
/* For len == 0, i is initialized to len - 1 which underflows.
* The condition (i < len) will then exit the for-loop on the
* first round which is correct. Similarly, loop termination
* happens by i underflowing.
*/
for (i = (idx_step >= 0 ? 0 : len - 1);
i < len; /* i >= 0 would always be true */
i += (duk_uint32_t) idx_step) {
DUK_DDD(DUK_DDDPRINT("i=%ld, len=%ld, have_acc=%ld, top=%ld, acc=%!T",
(long) i, (long) len, (long) have_acc,
(long) duk_get_top(thr),
(duk_tval *) duk_get_tval(thr, 4)));
DUK_ASSERT((have_acc && duk_get_top(thr) == 5) ||
(!have_acc && duk_get_top(thr) == 4));
if (!duk_has_prop_index(thr, 2, (duk_uarridx_t) i)) {
continue;
}
if (!have_acc) {
DUK_ASSERT_TOP(thr, 4);
duk_get_prop_index(thr, 2, (duk_uarridx_t) i);
have_acc = 1;
DUK_ASSERT_TOP(thr, 5);
} else {
DUK_ASSERT_TOP(thr, 5);
duk_dup_0(thr);
duk_dup(thr, 4);
duk_get_prop_index(thr, 2, (duk_uarridx_t) i);
duk_push_u32(thr, i);
duk_dup_2(thr);
DUK_DDD(DUK_DDDPRINT("calling reduce function: func=%!T, prev=%!T, curr=%!T, idx=%!T, obj=%!T",
(duk_tval *) duk_get_tval(thr, -5), (duk_tval *) duk_get_tval(thr, -4),
(duk_tval *) duk_get_tval(thr, -3), (duk_tval *) duk_get_tval(thr, -2),
(duk_tval *) duk_get_tval(thr, -1)));
duk_call(thr, 4);
DUK_DDD(DUK_DDDPRINT("-> result: %!T", (duk_tval *) duk_get_tval(thr, -1)));
duk_replace(thr, 4);
DUK_ASSERT_TOP(thr, 5);
}
}
if (!have_acc) {
DUK_DCERROR_TYPE_INVALID_ARGS(thr);
}
DUK_ASSERT_TOP(thr, 5);
return 1;
}
#endif /* DUK_USE_ARRAY_BUILTIN */
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