v8/src/array.js

1702 lines
50 KiB
JavaScript

// Copyright 2012 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// This file relies on the fact that the following declarations have been made
// in runtime.js:
// var $Array = global.Array;
// -------------------------------------------------------------------
// Global list of arrays visited during toString, toLocaleString and
// join invocations.
var visited_arrays = new InternalArray();
// Gets a sorted array of array keys. Useful for operations on sparse
// arrays. Dupes have not been removed.
function GetSortedArrayKeys(array, indices) {
var keys = new InternalArray();
if (IS_NUMBER(indices)) {
// It's an interval
var limit = indices;
for (var i = 0; i < limit; ++i) {
var e = array[i];
if (!IS_UNDEFINED(e) || i in array) {
keys.push(i);
}
}
} else {
var length = indices.length;
for (var k = 0; k < length; ++k) {
var key = indices[k];
if (!IS_UNDEFINED(key)) {
var e = array[key];
if (!IS_UNDEFINED(e) || key in array) {
keys.push(key);
}
}
}
%_CallFunction(keys, function(a, b) { return a - b; }, ArraySort);
}
return keys;
}
function SparseJoinWithSeparator(array, len, convert, separator) {
var keys = GetSortedArrayKeys(array, %GetArrayKeys(array, len));
var totalLength = 0;
var elements = new InternalArray(keys.length * 2);
var previousKey = -1;
for (var i = 0; i < keys.length; i++) {
var key = keys[i];
if (key != previousKey) { // keys may contain duplicates.
var e = array[key];
if (!IS_STRING(e)) e = convert(e);
elements[i * 2] = key;
elements[i * 2 + 1] = e;
previousKey = key;
}
}
return %SparseJoinWithSeparator(elements, len, separator);
}
// Optimized for sparse arrays if separator is ''.
function SparseJoin(array, len, convert) {
var keys = GetSortedArrayKeys(array, %GetArrayKeys(array, len));
var last_key = -1;
var keys_length = keys.length;
var elements = new InternalArray(keys_length);
var elements_length = 0;
for (var i = 0; i < keys_length; i++) {
var key = keys[i];
if (key != last_key) {
var e = array[key];
if (!IS_STRING(e)) e = convert(e);
elements[elements_length++] = e;
last_key = key;
}
}
return %StringBuilderConcat(elements, elements_length, '');
}
function UseSparseVariant(object, length, is_array) {
return is_array &&
length > 1000 &&
(!%_IsSmi(length) ||
%EstimateNumberOfElements(object) < (length >> 2));
}
function Join(array, length, separator, convert) {
if (length == 0) return '';
var is_array = IS_ARRAY(array);
if (is_array) {
// If the array is cyclic, return the empty string for already
// visited arrays.
if (!%PushIfAbsent(visited_arrays, array)) return '';
}
// Attempt to convert the elements.
try {
if (UseSparseVariant(array, length, is_array)) {
if (separator.length == 0) {
return SparseJoin(array, length, convert);
} else {
return SparseJoinWithSeparator(array, length, convert, separator);
}
}
// Fast case for one-element arrays.
if (length == 1) {
var e = array[0];
if (IS_STRING(e)) return e;
return convert(e);
}
// Construct an array for the elements.
var elements = new InternalArray(length);
// We pull the empty separator check outside the loop for speed!
if (separator.length == 0) {
var elements_length = 0;
for (var i = 0; i < length; i++) {
var e = array[i];
if (!IS_STRING(e)) e = convert(e);
elements[elements_length++] = e;
}
elements.length = elements_length;
var result = %_FastAsciiArrayJoin(elements, '');
if (!IS_UNDEFINED(result)) return result;
return %StringBuilderConcat(elements, elements_length, '');
}
// Non-empty separator case.
// If the first element is a number then use the heuristic that the
// remaining elements are also likely to be numbers.
if (!IS_NUMBER(array[0])) {
for (var i = 0; i < length; i++) {
var e = array[i];
if (!IS_STRING(e)) e = convert(e);
elements[i] = e;
}
} else {
for (var i = 0; i < length; i++) {
var e = array[i];
if (IS_NUMBER(e)) {
e = %_NumberToString(e);
} else if (!IS_STRING(e)) {
e = convert(e);
}
elements[i] = e;
}
}
var result = %_FastAsciiArrayJoin(elements, separator);
if (!IS_UNDEFINED(result)) return result;
return %StringBuilderJoin(elements, length, separator);
} finally {
// Make sure to remove the last element of the visited array no
// matter what happens.
if (is_array) visited_arrays.length = visited_arrays.length - 1;
}
}
function ConvertToString(x) {
// Assumes x is a non-string.
if (IS_NUMBER(x)) return %_NumberToString(x);
if (IS_BOOLEAN(x)) return x ? 'true' : 'false';
return (IS_NULL_OR_UNDEFINED(x)) ? '' : %ToString(%DefaultString(x));
}
function ConvertToLocaleString(e) {
if (IS_NULL_OR_UNDEFINED(e)) {
return '';
} else {
// According to ES5, section 15.4.4.3, the toLocaleString conversion
// must throw a TypeError if ToObject(e).toLocaleString isn't
// callable.
var e_obj = ToObject(e);
return %ToString(e_obj.toLocaleString());
}
}
// This function implements the optimized splice implementation that can use
// special array operations to handle sparse arrays in a sensible fashion.
function SmartSlice(array, start_i, del_count, len, deleted_elements) {
// Move deleted elements to a new array (the return value from splice).
var indices = %GetArrayKeys(array, start_i + del_count);
if (IS_NUMBER(indices)) {
var limit = indices;
for (var i = start_i; i < limit; ++i) {
var current = array[i];
if (!IS_UNDEFINED(current) || i in array) {
deleted_elements[i - start_i] = current;
}
}
} else {
var length = indices.length;
for (var k = 0; k < length; ++k) {
var key = indices[k];
if (!IS_UNDEFINED(key)) {
if (key >= start_i) {
var current = array[key];
if (!IS_UNDEFINED(current) || key in array) {
deleted_elements[key - start_i] = current;
}
}
}
}
}
}
// This function implements the optimized splice implementation that can use
// special array operations to handle sparse arrays in a sensible fashion.
function SmartMove(array, start_i, del_count, len, num_additional_args) {
// Move data to new array.
var new_array = new InternalArray(len - del_count + num_additional_args);
var indices = %GetArrayKeys(array, len);
if (IS_NUMBER(indices)) {
var limit = indices;
for (var i = 0; i < start_i && i < limit; ++i) {
var current = array[i];
if (!IS_UNDEFINED(current) || i in array) {
new_array[i] = current;
}
}
for (var i = start_i + del_count; i < limit; ++i) {
var current = array[i];
if (!IS_UNDEFINED(current) || i in array) {
new_array[i - del_count + num_additional_args] = current;
}
}
} else {
var length = indices.length;
for (var k = 0; k < length; ++k) {
var key = indices[k];
if (!IS_UNDEFINED(key)) {
if (key < start_i) {
var current = array[key];
if (!IS_UNDEFINED(current) || key in array) {
new_array[key] = current;
}
} else if (key >= start_i + del_count) {
var current = array[key];
if (!IS_UNDEFINED(current) || key in array) {
new_array[key - del_count + num_additional_args] = current;
}
}
}
}
}
// Move contents of new_array into this array
%MoveArrayContents(new_array, array);
}
// This is part of the old simple-minded splice. We are using it either
// because the receiver is not an array (so we have no choice) or because we
// know we are not deleting or moving a lot of elements.
function SimpleSlice(array, start_i, del_count, len, deleted_elements) {
for (var i = 0; i < del_count; i++) {
var index = start_i + i;
// The spec could also be interpreted such that %HasLocalProperty
// would be the appropriate test. We follow KJS in consulting the
// prototype.
var current = array[index];
if (!IS_UNDEFINED(current) || index in array) {
deleted_elements[i] = current;
}
}
}
function SimpleMove(array, start_i, del_count, len, num_additional_args) {
if (num_additional_args !== del_count) {
// Move the existing elements after the elements to be deleted
// to the right position in the resulting array.
if (num_additional_args > del_count) {
for (var i = len - del_count; i > start_i; i--) {
var from_index = i + del_count - 1;
var to_index = i + num_additional_args - 1;
// The spec could also be interpreted such that
// %HasLocalProperty would be the appropriate test. We follow
// KJS in consulting the prototype.
var current = array[from_index];
if (!IS_UNDEFINED(current) || from_index in array) {
array[to_index] = current;
} else {
delete array[to_index];
}
}
} else {
for (var i = start_i; i < len - del_count; i++) {
var from_index = i + del_count;
var to_index = i + num_additional_args;
// The spec could also be interpreted such that
// %HasLocalProperty would be the appropriate test. We follow
// KJS in consulting the prototype.
var current = array[from_index];
if (!IS_UNDEFINED(current) || from_index in array) {
array[to_index] = current;
} else {
delete array[to_index];
}
}
for (var i = len; i > len - del_count + num_additional_args; i--) {
delete array[i - 1];
}
}
}
}
// -------------------------------------------------------------------
function ArrayToString() {
var array;
var func;
if (IS_ARRAY(this)) {
func = this.join;
if (func === ArrayJoin) {
return Join(this, this.length, ',', ConvertToString);
}
array = this;
} else {
array = ToObject(this);
func = array.join;
}
if (!IS_SPEC_FUNCTION(func)) {
return %_CallFunction(array, ObjectToString);
}
return %_CallFunction(array, func);
}
function ArrayToLocaleString() {
var array = ToObject(this);
var arrayLen = array.length;
var len = TO_UINT32(arrayLen);
if (len === 0) return "";
return Join(array, len, ',', ConvertToLocaleString);
}
function ArrayJoin(separator) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.join"]);
}
var length = TO_UINT32(this.length);
if (IS_UNDEFINED(separator)) {
separator = ',';
} else if (!IS_STRING(separator)) {
separator = NonStringToString(separator);
}
var result = %_FastAsciiArrayJoin(this, separator);
if (!IS_UNDEFINED(result)) return result;
return Join(this, length, separator, ConvertToString);
}
function ObservedArrayPop(n) {
n--;
var value = this[n];
try {
BeginPerformSplice(this);
delete this[n];
this.length = n;
} finally {
EndPerformSplice(this);
EnqueueSpliceRecord(this, n, [value], 0);
}
return value;
}
// Removes the last element from the array and returns it. See
// ECMA-262, section 15.4.4.6.
function ArrayPop() {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.pop"]);
}
var n = TO_UINT32(this.length);
if (n == 0) {
this.length = n;
return;
}
if ($Object.isSealed(this)) {
throw MakeTypeError("array_functions_change_sealed",
["Array.prototype.pop"]);
}
if (%IsObserved(this))
return ObservedArrayPop.call(this, n);
n--;
var value = this[n];
Delete(this, ToName(n), true);
this.length = n;
return value;
}
function ObservedArrayPush() {
var n = TO_UINT32(this.length);
var m = %_ArgumentsLength();
try {
BeginPerformSplice(this);
for (var i = 0; i < m; i++) {
this[i+n] = %_Arguments(i);
}
this.length = n + m;
} finally {
EndPerformSplice(this);
EnqueueSpliceRecord(this, n, [], m);
}
return this.length;
}
// Appends the arguments to the end of the array and returns the new
// length of the array. See ECMA-262, section 15.4.4.7.
function ArrayPush() {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.push"]);
}
var n = TO_UINT32(this.length);
var m = %_ArgumentsLength();
if (m > 0 && $Object.isSealed(this)) {
throw MakeTypeError("array_functions_change_sealed",
["Array.prototype.push"]);
}
if (%IsObserved(this))
return ObservedArrayPush.apply(this, arguments);
for (var i = 0; i < m; i++) {
this[i+n] = %_Arguments(i);
}
this.length = n + m;
return this.length;
}
// Returns an array containing the array elements of the object followed
// by the array elements of each argument in order. See ECMA-262,
// section 15.4.4.7.
function ArrayConcat(arg1) { // length == 1
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.concat"]);
}
var array = ToObject(this);
var arg_count = %_ArgumentsLength();
var arrays = new InternalArray(1 + arg_count);
arrays[0] = array;
for (var i = 0; i < arg_count; i++) {
arrays[i + 1] = %_Arguments(i);
}
return %ArrayConcat(arrays);
}
// For implementing reverse() on large, sparse arrays.
function SparseReverse(array, len) {
var keys = GetSortedArrayKeys(array, %GetArrayKeys(array, len));
var high_counter = keys.length - 1;
var low_counter = 0;
while (low_counter <= high_counter) {
var i = keys[low_counter];
var j = keys[high_counter];
var j_complement = len - j - 1;
var low, high;
if (j_complement <= i) {
high = j;
while (keys[--high_counter] == j) { }
low = j_complement;
}
if (j_complement >= i) {
low = i;
while (keys[++low_counter] == i) { }
high = len - i - 1;
}
var current_i = array[low];
if (!IS_UNDEFINED(current_i) || low in array) {
var current_j = array[high];
if (!IS_UNDEFINED(current_j) || high in array) {
array[low] = current_j;
array[high] = current_i;
} else {
array[high] = current_i;
delete array[low];
}
} else {
var current_j = array[high];
if (!IS_UNDEFINED(current_j) || high in array) {
array[low] = current_j;
delete array[high];
}
}
}
}
function ArrayReverse() {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.reverse"]);
}
var j = TO_UINT32(this.length) - 1;
if (UseSparseVariant(this, j, IS_ARRAY(this))) {
SparseReverse(this, j+1);
return this;
}
for (var i = 0; i < j; i++, j--) {
var current_i = this[i];
if (!IS_UNDEFINED(current_i) || i in this) {
var current_j = this[j];
if (!IS_UNDEFINED(current_j) || j in this) {
this[i] = current_j;
this[j] = current_i;
} else {
this[j] = current_i;
delete this[i];
}
} else {
var current_j = this[j];
if (!IS_UNDEFINED(current_j) || j in this) {
this[i] = current_j;
delete this[j];
}
}
}
return this;
}
function ObservedArrayShift(len) {
var first = this[0];
try {
BeginPerformSplice(this);
SimpleMove(this, 0, 1, len, 0);
this.length = len - 1;
} finally {
EndPerformSplice(this);
EnqueueSpliceRecord(this, 0, [first], 0);
}
return first;
}
function ArrayShift() {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.shift"]);
}
var len = TO_UINT32(this.length);
if (len === 0) {
this.length = 0;
return;
}
if ($Object.isSealed(this)) {
throw MakeTypeError("array_functions_change_sealed",
["Array.prototype.shift"]);
}
if (%IsObserved(this))
return ObservedArrayShift.call(this, len);
var first = this[0];
if (IS_ARRAY(this)) {
SmartMove(this, 0, 1, len, 0);
} else {
SimpleMove(this, 0, 1, len, 0);
}
this.length = len - 1;
return first;
}
function ObservedArrayUnshift() {
var len = TO_UINT32(this.length);
var num_arguments = %_ArgumentsLength();
try {
BeginPerformSplice(this);
SimpleMove(this, 0, 0, len, num_arguments);
for (var i = 0; i < num_arguments; i++) {
this[i] = %_Arguments(i);
}
this.length = len + num_arguments;
} finally {
EndPerformSplice(this);
EnqueueSpliceRecord(this, 0, [], num_arguments);
}
return len + num_arguments;
}
function ArrayUnshift(arg1) { // length == 1
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.unshift"]);
}
var len = TO_UINT32(this.length);
var num_arguments = %_ArgumentsLength();
var is_sealed = $Object.isSealed(this);
if (num_arguments > 0 && is_sealed) {
throw MakeTypeError("array_functions_change_sealed",
["Array.prototype.unshift"]);
}
if (%IsObserved(this))
return ObservedArrayUnshift.apply(this, arguments);
if (IS_ARRAY(this) && !is_sealed) {
SmartMove(this, 0, 0, len, num_arguments);
} else {
if (num_arguments == 0 && $Object.isFrozen(this)) {
// In the zero argument case, values from the prototype come into the
// object. This can't be allowed on frozen arrays.
for (var i = 0; i < len; i++) {
if (!this.hasOwnProperty(i) && !IS_UNDEFINED(this[i])) {
throw MakeTypeError("array_functions_on_frozen",
["Array.prototype.shift"]);
}
}
}
SimpleMove(this, 0, 0, len, num_arguments);
}
for (var i = 0; i < num_arguments; i++) {
this[i] = %_Arguments(i);
}
this.length = len + num_arguments;
return this.length;
}
function ArraySlice(start, end) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.slice"]);
}
var len = TO_UINT32(this.length);
var start_i = TO_INTEGER(start);
var end_i = len;
if (!IS_UNDEFINED(end)) end_i = TO_INTEGER(end);
if (start_i < 0) {
start_i += len;
if (start_i < 0) start_i = 0;
} else {
if (start_i > len) start_i = len;
}
if (end_i < 0) {
end_i += len;
if (end_i < 0) end_i = 0;
} else {
if (end_i > len) end_i = len;
}
var result = [];
if (end_i < start_i) return result;
if (IS_ARRAY(this) &&
!%IsObserved(this) &&
(end_i > 1000) &&
(%EstimateNumberOfElements(this) < end_i)) {
SmartSlice(this, start_i, end_i - start_i, len, result);
} else {
SimpleSlice(this, start_i, end_i - start_i, len, result);
}
result.length = end_i - start_i;
return result;
}
function ComputeSpliceStartIndex(start_i, len) {
if (start_i < 0) {
start_i += len;
return start_i < 0 ? 0 : start_i;
}
return start_i > len ? len : start_i;
}
function ComputeSpliceDeleteCount(delete_count, num_arguments, len, start_i) {
// SpiderMonkey, TraceMonkey and JSC treat the case where no delete count is
// given as a request to delete all the elements from the start.
// And it differs from the case of undefined delete count.
// This does not follow ECMA-262, but we do the same for
// compatibility.
var del_count = 0;
if (num_arguments == 1)
return len - start_i;
del_count = TO_INTEGER(delete_count);
if (del_count < 0)
return 0;
if (del_count > len - start_i)
return len - start_i;
return del_count;
}
function ObservedArraySplice(start, delete_count) {
var num_arguments = %_ArgumentsLength();
var len = TO_UINT32(this.length);
var start_i = ComputeSpliceStartIndex(TO_INTEGER(start), len);
var del_count = ComputeSpliceDeleteCount(delete_count, num_arguments, len,
start_i);
var deleted_elements = [];
deleted_elements.length = del_count;
var num_elements_to_add = num_arguments > 2 ? num_arguments - 2 : 0;
try {
BeginPerformSplice(this);
SimpleSlice(this, start_i, del_count, len, deleted_elements);
SimpleMove(this, start_i, del_count, len, num_elements_to_add);
// Insert the arguments into the resulting array in
// place of the deleted elements.
var i = start_i;
var arguments_index = 2;
var arguments_length = %_ArgumentsLength();
while (arguments_index < arguments_length) {
this[i++] = %_Arguments(arguments_index++);
}
this.length = len - del_count + num_elements_to_add;
} finally {
EndPerformSplice(this);
if (deleted_elements.length || num_elements_to_add) {
EnqueueSpliceRecord(this,
start_i,
deleted_elements.slice(),
num_elements_to_add);
}
}
// Return the deleted elements.
return deleted_elements;
}
function ArraySplice(start, delete_count) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.splice"]);
}
if (%IsObserved(this))
return ObservedArraySplice.apply(this, arguments);
var num_arguments = %_ArgumentsLength();
var len = TO_UINT32(this.length);
var start_i = ComputeSpliceStartIndex(TO_INTEGER(start), len);
var del_count = ComputeSpliceDeleteCount(delete_count, num_arguments, len,
start_i);
var deleted_elements = [];
deleted_elements.length = del_count;
var num_elements_to_add = num_arguments > 2 ? num_arguments - 2 : 0;
if (del_count != num_elements_to_add && $Object.isSealed(this)) {
throw MakeTypeError("array_functions_change_sealed",
["Array.prototype.splice"]);
} else if (del_count > 0 && $Object.isFrozen(this)) {
throw MakeTypeError("array_functions_on_frozen",
["Array.prototype.splice"]);
}
var use_simple_splice = true;
if (IS_ARRAY(this) &&
num_elements_to_add !== del_count) {
// If we are only deleting/moving a few things near the end of the
// array then the simple version is going to be faster, because it
// doesn't touch most of the array.
var estimated_non_hole_elements = %EstimateNumberOfElements(this);
if (len > 20 && (estimated_non_hole_elements >> 2) < (len - start_i)) {
use_simple_splice = false;
}
}
if (use_simple_splice) {
SimpleSlice(this, start_i, del_count, len, deleted_elements);
SimpleMove(this, start_i, del_count, len, num_elements_to_add);
} else {
SmartSlice(this, start_i, del_count, len, deleted_elements);
SmartMove(this, start_i, del_count, len, num_elements_to_add);
}
// Insert the arguments into the resulting array in
// place of the deleted elements.
var i = start_i;
var arguments_index = 2;
var arguments_length = %_ArgumentsLength();
while (arguments_index < arguments_length) {
this[i++] = %_Arguments(arguments_index++);
}
this.length = len - del_count + num_elements_to_add;
// Return the deleted elements.
return deleted_elements;
}
function ArraySort(comparefn) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.sort"]);
}
// In-place QuickSort algorithm.
// For short (length <= 22) arrays, insertion sort is used for efficiency.
if (!IS_SPEC_FUNCTION(comparefn)) {
comparefn = function (x, y) {
if (x === y) return 0;
if (%_IsSmi(x) && %_IsSmi(y)) {
return %SmiLexicographicCompare(x, y);
}
x = ToString(x);
y = ToString(y);
if (x == y) return 0;
else return x < y ? -1 : 1;
};
}
var receiver = %GetDefaultReceiver(comparefn);
var InsertionSort = function InsertionSort(a, from, to) {
for (var i = from + 1; i < to; i++) {
var element = a[i];
for (var j = i - 1; j >= from; j--) {
var tmp = a[j];
var order = %_CallFunction(receiver, tmp, element, comparefn);
if (order > 0) {
a[j + 1] = tmp;
} else {
break;
}
}
a[j + 1] = element;
}
};
var GetThirdIndex = function(a, from, to) {
var t_array = [];
// Use both 'from' and 'to' to determine the pivot candidates.
var increment = 200 + ((to - from) & 15);
for (var i = from + 1; i < to - 1; i += increment) {
t_array.push([i, a[i]]);
}
t_array.sort(function(a, b) {
return %_CallFunction(receiver, a[1], b[1], comparefn) } );
var third_index = t_array[t_array.length >> 1][0];
return third_index;
}
var QuickSort = function QuickSort(a, from, to) {
var third_index = 0;
while (true) {
// Insertion sort is faster for short arrays.
if (to - from <= 10) {
InsertionSort(a, from, to);
return;
}
if (to - from > 1000) {
third_index = GetThirdIndex(a, from, to);
} else {
third_index = from + ((to - from) >> 1);
}
// Find a pivot as the median of first, last and middle element.
var v0 = a[from];
var v1 = a[to - 1];
var v2 = a[third_index];
var c01 = %_CallFunction(receiver, v0, v1, comparefn);
if (c01 > 0) {
// v1 < v0, so swap them.
var tmp = v0;
v0 = v1;
v1 = tmp;
} // v0 <= v1.
var c02 = %_CallFunction(receiver, v0, v2, comparefn);
if (c02 >= 0) {
// v2 <= v0 <= v1.
var tmp = v0;
v0 = v2;
v2 = v1;
v1 = tmp;
} else {
// v0 <= v1 && v0 < v2
var c12 = %_CallFunction(receiver, v1, v2, comparefn);
if (c12 > 0) {
// v0 <= v2 < v1
var tmp = v1;
v1 = v2;
v2 = tmp;
}
}
// v0 <= v1 <= v2
a[from] = v0;
a[to - 1] = v2;
var pivot = v1;
var low_end = from + 1; // Upper bound of elements lower than pivot.
var high_start = to - 1; // Lower bound of elements greater than pivot.
a[third_index] = a[low_end];
a[low_end] = pivot;
// From low_end to i are elements equal to pivot.
// From i to high_start are elements that haven't been compared yet.
partition: for (var i = low_end + 1; i < high_start; i++) {
var element = a[i];
var order = %_CallFunction(receiver, element, pivot, comparefn);
if (order < 0) {
a[i] = a[low_end];
a[low_end] = element;
low_end++;
} else if (order > 0) {
do {
high_start--;
if (high_start == i) break partition;
var top_elem = a[high_start];
order = %_CallFunction(receiver, top_elem, pivot, comparefn);
} while (order > 0);
a[i] = a[high_start];
a[high_start] = element;
if (order < 0) {
element = a[i];
a[i] = a[low_end];
a[low_end] = element;
low_end++;
}
}
}
if (to - high_start < low_end - from) {
QuickSort(a, high_start, to);
to = low_end;
} else {
QuickSort(a, from, low_end);
from = high_start;
}
}
};
// Copy elements in the range 0..length from obj's prototype chain
// to obj itself, if obj has holes. Return one more than the maximal index
// of a prototype property.
var CopyFromPrototype = function CopyFromPrototype(obj, length) {
var max = 0;
for (var proto = %GetPrototype(obj); proto; proto = %GetPrototype(proto)) {
var indices = %GetArrayKeys(proto, length);
if (IS_NUMBER(indices)) {
// It's an interval.
var proto_length = indices;
for (var i = 0; i < proto_length; i++) {
if (!obj.hasOwnProperty(i) && proto.hasOwnProperty(i)) {
obj[i] = proto[i];
if (i >= max) { max = i + 1; }
}
}
} else {
for (var i = 0; i < indices.length; i++) {
var index = indices[i];
if (!IS_UNDEFINED(index) &&
!obj.hasOwnProperty(index) && proto.hasOwnProperty(index)) {
obj[index] = proto[index];
if (index >= max) { max = index + 1; }
}
}
}
}
return max;
};
// Set a value of "undefined" on all indices in the range from..to
// where a prototype of obj has an element. I.e., shadow all prototype
// elements in that range.
var ShadowPrototypeElements = function(obj, from, to) {
for (var proto = %GetPrototype(obj); proto; proto = %GetPrototype(proto)) {
var indices = %GetArrayKeys(proto, to);
if (IS_NUMBER(indices)) {
// It's an interval.
var proto_length = indices;
for (var i = from; i < proto_length; i++) {
if (proto.hasOwnProperty(i)) {
obj[i] = UNDEFINED;
}
}
} else {
for (var i = 0; i < indices.length; i++) {
var index = indices[i];
if (!IS_UNDEFINED(index) && from <= index &&
proto.hasOwnProperty(index)) {
obj[index] = UNDEFINED;
}
}
}
}
};
var SafeRemoveArrayHoles = function SafeRemoveArrayHoles(obj) {
// Copy defined elements from the end to fill in all holes and undefineds
// in the beginning of the array. Write undefineds and holes at the end
// after loop is finished.
var first_undefined = 0;
var last_defined = length - 1;
var num_holes = 0;
while (first_undefined < last_defined) {
// Find first undefined element.
while (first_undefined < last_defined &&
!IS_UNDEFINED(obj[first_undefined])) {
first_undefined++;
}
// Maintain the invariant num_holes = the number of holes in the original
// array with indices <= first_undefined or > last_defined.
if (!obj.hasOwnProperty(first_undefined)) {
num_holes++;
}
// Find last defined element.
while (first_undefined < last_defined &&
IS_UNDEFINED(obj[last_defined])) {
if (!obj.hasOwnProperty(last_defined)) {
num_holes++;
}
last_defined--;
}
if (first_undefined < last_defined) {
// Fill in hole or undefined.
obj[first_undefined] = obj[last_defined];
obj[last_defined] = UNDEFINED;
}
}
// If there were any undefineds in the entire array, first_undefined
// points to one past the last defined element. Make this true if
// there were no undefineds, as well, so that first_undefined == number
// of defined elements.
if (!IS_UNDEFINED(obj[first_undefined])) first_undefined++;
// Fill in the undefineds and the holes. There may be a hole where
// an undefined should be and vice versa.
var i;
for (i = first_undefined; i < length - num_holes; i++) {
obj[i] = UNDEFINED;
}
for (i = length - num_holes; i < length; i++) {
// For compatability with Webkit, do not expose elements in the prototype.
if (i in %GetPrototype(obj)) {
obj[i] = UNDEFINED;
} else {
delete obj[i];
}
}
// Return the number of defined elements.
return first_undefined;
};
var length = TO_UINT32(this.length);
if (length < 2) return this;
var is_array = IS_ARRAY(this);
var max_prototype_element;
if (!is_array) {
// For compatibility with JSC, we also sort elements inherited from
// the prototype chain on non-Array objects.
// We do this by copying them to this object and sorting only
// local elements. This is not very efficient, but sorting with
// inherited elements happens very, very rarely, if at all.
// The specification allows "implementation dependent" behavior
// if an element on the prototype chain has an element that
// might interact with sorting.
max_prototype_element = CopyFromPrototype(this, length);
}
var num_non_undefined = %IsObserved(this) ?
-1 : %RemoveArrayHoles(this, length);
if (num_non_undefined == -1) {
// The array is observed, or there were indexed accessors in the array.
// Move array holes and undefineds to the end using a Javascript function
// that is safe in the presence of accessors and is observable.
num_non_undefined = SafeRemoveArrayHoles(this);
}
QuickSort(this, 0, num_non_undefined);
if (!is_array && (num_non_undefined + 1 < max_prototype_element)) {
// For compatibility with JSC, we shadow any elements in the prototype
// chain that has become exposed by sort moving a hole to its position.
ShadowPrototypeElements(this, num_non_undefined, max_prototype_element);
}
return this;
}
// The following functions cannot be made efficient on sparse arrays while
// preserving the semantics, since the calls to the receiver function can add
// or delete elements from the array.
function ArrayFilter(f, receiver) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.filter"]);
}
// Pull out the length so that modifications to the length in the
// loop will not affect the looping and side effects are visible.
var array = ToObject(this);
var length = ToUint32(array.length);
if (!IS_SPEC_FUNCTION(f)) {
throw MakeTypeError('called_non_callable', [ f ]);
}
if (IS_NULL_OR_UNDEFINED(receiver)) {
receiver = %GetDefaultReceiver(f) || receiver;
} else if (!IS_SPEC_OBJECT(receiver) && %IsClassicModeFunction(f)) {
receiver = ToObject(receiver);
}
var result = new $Array();
var accumulator = new InternalArray();
var accumulator_length = 0;
if (%DebugCallbackSupportsStepping(f)) {
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
// Prepare break slots for debugger step in.
%DebugPrepareStepInIfStepping(f);
if (%_CallFunction(receiver, element, i, array, f)) {
accumulator[accumulator_length++] = element;
}
}
}
} else {
// This is a duplicate of the previous loop sans debug stepping.
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
if (%_CallFunction(receiver, element, i, array, f)) {
accumulator[accumulator_length++] = element;
}
}
}
// End of duplicate.
}
%MoveArrayContents(accumulator, result);
return result;
}
function ArrayForEach(f, receiver) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.forEach"]);
}
// Pull out the length so that modifications to the length in the
// loop will not affect the looping and side effects are visible.
var array = ToObject(this);
var length = TO_UINT32(array.length);
if (!IS_SPEC_FUNCTION(f)) {
throw MakeTypeError('called_non_callable', [ f ]);
}
if (IS_NULL_OR_UNDEFINED(receiver)) {
receiver = %GetDefaultReceiver(f) || receiver;
} else if (!IS_SPEC_OBJECT(receiver) && %IsClassicModeFunction(f)) {
receiver = ToObject(receiver);
}
if (%DebugCallbackSupportsStepping(f)) {
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
// Prepare break slots for debugger step in.
%DebugPrepareStepInIfStepping(f);
%_CallFunction(receiver, element, i, array, f);
}
}
} else {
// This is a duplicate of the previous loop sans debug stepping.
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
%_CallFunction(receiver, element, i, array, f);
}
}
// End of duplicate.
}
}
// Executes the function once for each element present in the
// array until it finds one where callback returns true.
function ArraySome(f, receiver) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.some"]);
}
// Pull out the length so that modifications to the length in the
// loop will not affect the looping and side effects are visible.
var array = ToObject(this);
var length = TO_UINT32(array.length);
if (!IS_SPEC_FUNCTION(f)) {
throw MakeTypeError('called_non_callable', [ f ]);
}
if (IS_NULL_OR_UNDEFINED(receiver)) {
receiver = %GetDefaultReceiver(f) || receiver;
} else if (!IS_SPEC_OBJECT(receiver) && %IsClassicModeFunction(f)) {
receiver = ToObject(receiver);
}
if (%DebugCallbackSupportsStepping(f)) {
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
// Prepare break slots for debugger step in.
%DebugPrepareStepInIfStepping(f);
if (%_CallFunction(receiver, element, i, array, f)) return true;
}
}
} else {
// This is a duplicate of the previous loop sans debug stepping.
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
if (%_CallFunction(receiver, element, i, array, f)) return true;
}
}
// End of duplicate.
}
return false;
}
function ArrayEvery(f, receiver) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.every"]);
}
// Pull out the length so that modifications to the length in the
// loop will not affect the looping and side effects are visible.
var array = ToObject(this);
var length = TO_UINT32(array.length);
if (!IS_SPEC_FUNCTION(f)) {
throw MakeTypeError('called_non_callable', [ f ]);
}
if (IS_NULL_OR_UNDEFINED(receiver)) {
receiver = %GetDefaultReceiver(f) || receiver;
} else if (!IS_SPEC_OBJECT(receiver) && %IsClassicModeFunction(f)) {
receiver = ToObject(receiver);
}
if (%DebugCallbackSupportsStepping(f)) {
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
// Prepare break slots for debugger step in.
%DebugPrepareStepInIfStepping(f);
if (!%_CallFunction(receiver, element, i, array, f)) return false;
}
}
} else {
// This is a duplicate of the previous loop sans debug stepping.
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
if (!%_CallFunction(receiver, element, i, array, f)) return false;
}
}
// End of duplicate.
}
return true;
}
function ArrayMap(f, receiver) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.map"]);
}
// Pull out the length so that modifications to the length in the
// loop will not affect the looping and side effects are visible.
var array = ToObject(this);
var length = TO_UINT32(array.length);
if (!IS_SPEC_FUNCTION(f)) {
throw MakeTypeError('called_non_callable', [ f ]);
}
if (IS_NULL_OR_UNDEFINED(receiver)) {
receiver = %GetDefaultReceiver(f) || receiver;
} else if (!IS_SPEC_OBJECT(receiver) && %IsClassicModeFunction(f)) {
receiver = ToObject(receiver);
}
var result = new $Array();
var accumulator = new InternalArray(length);
if (%DebugCallbackSupportsStepping(f)) {
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
// Prepare break slots for debugger step in.
%DebugPrepareStepInIfStepping(f);
accumulator[i] = %_CallFunction(receiver, element, i, array, f);
}
}
} else {
// This is a duplicate of the previous loop sans debug stepping.
for (var i = 0; i < length; i++) {
if (i in array) {
var element = array[i];
accumulator[i] = %_CallFunction(receiver, element, i, array, f);
}
}
// End of duplicate.
}
%MoveArrayContents(accumulator, result);
return result;
}
function ArrayIndexOf(element, index) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.indexOf"]);
}
var length = TO_UINT32(this.length);
if (length == 0) return -1;
if (IS_UNDEFINED(index)) {
index = 0;
} else {
index = TO_INTEGER(index);
// If index is negative, index from the end of the array.
if (index < 0) {
index = length + index;
// If index is still negative, search the entire array.
if (index < 0) index = 0;
}
}
var min = index;
var max = length;
if (UseSparseVariant(this, length, IS_ARRAY(this))) {
var indices = %GetArrayKeys(this, length);
if (IS_NUMBER(indices)) {
// It's an interval.
max = indices; // Capped by length already.
// Fall through to loop below.
} else {
if (indices.length == 0) return -1;
// Get all the keys in sorted order.
var sortedKeys = GetSortedArrayKeys(this, indices);
var n = sortedKeys.length;
var i = 0;
while (i < n && sortedKeys[i] < index) i++;
while (i < n) {
var key = sortedKeys[i];
if (!IS_UNDEFINED(key) && this[key] === element) return key;
i++;
}
return -1;
}
}
// Lookup through the array.
if (!IS_UNDEFINED(element)) {
for (var i = min; i < max; i++) {
if (this[i] === element) return i;
}
return -1;
}
// Lookup through the array.
for (var i = min; i < max; i++) {
if (IS_UNDEFINED(this[i]) && i in this) {
return i;
}
}
return -1;
}
function ArrayLastIndexOf(element, index) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.lastIndexOf"]);
}
var length = TO_UINT32(this.length);
if (length == 0) return -1;
if (%_ArgumentsLength() < 2) {
index = length - 1;
} else {
index = TO_INTEGER(index);
// If index is negative, index from end of the array.
if (index < 0) index += length;
// If index is still negative, do not search the array.
if (index < 0) return -1;
else if (index >= length) index = length - 1;
}
var min = 0;
var max = index;
if (UseSparseVariant(this, length, IS_ARRAY(this))) {
var indices = %GetArrayKeys(this, index + 1);
if (IS_NUMBER(indices)) {
// It's an interval.
max = indices; // Capped by index already.
// Fall through to loop below.
} else {
if (indices.length == 0) return -1;
// Get all the keys in sorted order.
var sortedKeys = GetSortedArrayKeys(this, indices);
var i = sortedKeys.length - 1;
while (i >= 0) {
var key = sortedKeys[i];
if (!IS_UNDEFINED(key) && this[key] === element) return key;
i--;
}
return -1;
}
}
// Lookup through the array.
if (!IS_UNDEFINED(element)) {
for (var i = max; i >= min; i--) {
if (this[i] === element) return i;
}
return -1;
}
for (var i = max; i >= min; i--) {
if (IS_UNDEFINED(this[i]) && i in this) {
return i;
}
}
return -1;
}
function ArrayReduce(callback, current) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.reduce"]);
}
// Pull out the length so that modifications to the length in the
// loop will not affect the looping and side effects are visible.
var array = ToObject(this);
var length = ToUint32(array.length);
if (!IS_SPEC_FUNCTION(callback)) {
throw MakeTypeError('called_non_callable', [callback]);
}
var i = 0;
find_initial: if (%_ArgumentsLength() < 2) {
for (; i < length; i++) {
current = array[i];
if (!IS_UNDEFINED(current) || i in array) {
i++;
break find_initial;
}
}
throw MakeTypeError('reduce_no_initial', []);
}
var receiver = %GetDefaultReceiver(callback);
if (%DebugCallbackSupportsStepping(callback)) {
for (; i < length; i++) {
if (i in array) {
var element = array[i];
// Prepare break slots for debugger step in.
%DebugPrepareStepInIfStepping(callback);
current =
%_CallFunction(receiver, current, element, i, array, callback);
}
}
} else {
// This is a duplicate of the previous loop sans debug stepping.
for (; i < length; i++) {
if (i in array) {
var element = array[i];
current =
%_CallFunction(receiver, current, element, i, array, callback);
}
}
// End of duplicate.
}
return current;
}
function ArrayReduceRight(callback, current) {
if (IS_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined",
["Array.prototype.reduceRight"]);
}
// Pull out the length so that side effects are visible before the
// callback function is checked.
var array = ToObject(this);
var length = ToUint32(array.length);
if (!IS_SPEC_FUNCTION(callback)) {
throw MakeTypeError('called_non_callable', [callback]);
}
var i = length - 1;
find_initial: if (%_ArgumentsLength() < 2) {
for (; i >= 0; i--) {
current = array[i];
if (!IS_UNDEFINED(current) || i in array) {
i--;
break find_initial;
}
}
throw MakeTypeError('reduce_no_initial', []);
}
var receiver = %GetDefaultReceiver(callback);
if (%DebugCallbackSupportsStepping(callback)) {
for (; i >= 0; i--) {
if (i in array) {
var element = array[i];
// Prepare break slots for debugger step in.
%DebugPrepareStepInIfStepping(callback);
current =
%_CallFunction(receiver, current, element, i, array, callback);
}
}
} else {
// This is a duplicate of the previous loop sans debug stepping.
for (; i >= 0; i--) {
if (i in array) {
var element = array[i];
current =
%_CallFunction(receiver, current, element, i, array, callback);
}
}
// End of duplicate.
}
return current;
}
// ES5, 15.4.3.2
function ArrayIsArray(obj) {
return IS_ARRAY(obj);
}
// -------------------------------------------------------------------
function SetUpArray() {
%CheckIsBootstrapping();
// Set up non-enumerable constructor property on the Array.prototype
// object.
%SetProperty($Array.prototype, "constructor", $Array, DONT_ENUM);
// Set up non-enumerable functions on the Array object.
InstallFunctions($Array, DONT_ENUM, $Array(
"isArray", ArrayIsArray
));
var specialFunctions = %SpecialArrayFunctions({});
var getFunction = function(name, jsBuiltin, len) {
var f = jsBuiltin;
if (specialFunctions.hasOwnProperty(name)) {
f = specialFunctions[name];
}
if (!IS_UNDEFINED(len)) {
%FunctionSetLength(f, len);
}
return f;
};
// Set up non-enumerable functions of the Array.prototype object and
// set their names.
// Manipulate the length of some of the functions to meet
// expectations set by ECMA-262 or Mozilla.
InstallFunctions($Array.prototype, DONT_ENUM, $Array(
"toString", getFunction("toString", ArrayToString),
"toLocaleString", getFunction("toLocaleString", ArrayToLocaleString),
"join", getFunction("join", ArrayJoin),
"pop", getFunction("pop", ArrayPop),
"push", getFunction("push", ArrayPush, 1),
"concat", getFunction("concat", ArrayConcat, 1),
"reverse", getFunction("reverse", ArrayReverse),
"shift", getFunction("shift", ArrayShift),
"unshift", getFunction("unshift", ArrayUnshift, 1),
"slice", getFunction("slice", ArraySlice, 2),
"splice", getFunction("splice", ArraySplice, 2),
"sort", getFunction("sort", ArraySort),
"filter", getFunction("filter", ArrayFilter, 1),
"forEach", getFunction("forEach", ArrayForEach, 1),
"some", getFunction("some", ArraySome, 1),
"every", getFunction("every", ArrayEvery, 1),
"map", getFunction("map", ArrayMap, 1),
"indexOf", getFunction("indexOf", ArrayIndexOf, 1),
"lastIndexOf", getFunction("lastIndexOf", ArrayLastIndexOf, 1),
"reduce", getFunction("reduce", ArrayReduce, 1),
"reduceRight", getFunction("reduceRight", ArrayReduceRight, 1)
));
%FinishArrayPrototypeSetup($Array.prototype);
// The internal Array prototype doesn't need to be fancy, since it's never
// exposed to user code.
// Adding only the functions that are actually used.
SetUpLockedPrototype(InternalArray, $Array(), $Array(
"concat", getFunction("concat", ArrayConcat),
"indexOf", getFunction("indexOf", ArrayIndexOf),
"join", getFunction("join", ArrayJoin),
"pop", getFunction("pop", ArrayPop),
"push", getFunction("push", ArrayPush),
"splice", getFunction("splice", ArraySplice)
));
SetUpLockedPrototype(InternalPackedArray, $Array(), $Array(
"join", getFunction("join", ArrayJoin),
"pop", getFunction("pop", ArrayPop),
"push", getFunction("push", ArrayPush)
));
}
SetUpArray();