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-rw-r--r--js/src/builtin/Array.cpp4330
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diff --git a/js/src/builtin/Array.cpp b/js/src/builtin/Array.cpp
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+++ b/js/src/builtin/Array.cpp
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "builtin/Array-inl.h"
+
+#include "mozilla/CheckedInt.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/MathAlgorithms.h"
+#include "mozilla/Maybe.h"
+#include "mozilla/TextUtils.h"
+
+#include <algorithm>
+#include <iterator>
+
+#include "jsapi.h"
+#include "jsfriendapi.h"
+#include "jsnum.h"
+#include "jstypes.h"
+
+#include "ds/Sort.h"
+#include "gc/Allocator.h"
+#include "jit/InlinableNatives.h"
+#include "js/Class.h"
+#include "js/Conversions.h"
+#include "js/experimental/JitInfo.h" // JSJitGetterOp, JSJitInfo
+#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_*
+#include "js/friend/StackLimits.h" // js::CheckRecursionLimit
+#include "js/PropertySpec.h"
+#include "util/Poison.h"
+#include "util/StringBuffer.h"
+#include "util/Text.h"
+#include "vm/ArgumentsObject.h"
+#include "vm/Interpreter.h"
+#include "vm/Iteration.h"
+#include "vm/JSAtom.h"
+#include "vm/JSContext.h"
+#include "vm/JSFunction.h"
+#include "vm/JSObject.h"
+#include "vm/PlainObject.h" // js::PlainObject
+#include "vm/SelfHosting.h"
+#include "vm/Shape.h"
+#include "vm/ToSource.h" // js::ValueToSource
+#include "vm/TypedArrayObject.h"
+#include "vm/WrapperObject.h"
+
+#include "vm/ArgumentsObject-inl.h"
+#include "vm/ArrayObject-inl.h"
+#include "vm/Caches-inl.h"
+#include "vm/GeckoProfiler-inl.h"
+#include "vm/Interpreter-inl.h"
+#include "vm/IsGivenTypeObject-inl.h"
+#include "vm/JSAtom-inl.h"
+#include "vm/NativeObject-inl.h"
+
+using namespace js;
+
+using mozilla::Abs;
+using mozilla::CeilingLog2;
+using mozilla::CheckedInt;
+using mozilla::DebugOnly;
+using mozilla::IsAsciiDigit;
+using mozilla::Maybe;
+
+using JS::AutoCheckCannotGC;
+using JS::IsArrayAnswer;
+using JS::ToUint32;
+
+bool JS::IsArray(JSContext* cx, HandleObject obj, IsArrayAnswer* answer) {
+ if (obj->is<ArrayObject>()) {
+ *answer = IsArrayAnswer::Array;
+ return true;
+ }
+
+ if (obj->is<ProxyObject>()) {
+ return Proxy::isArray(cx, obj, answer);
+ }
+
+ *answer = IsArrayAnswer::NotArray;
+ return true;
+}
+
+bool JS::IsArray(JSContext* cx, HandleObject obj, bool* isArray) {
+ IsArrayAnswer answer;
+ if (!IsArray(cx, obj, &answer)) {
+ return false;
+ }
+
+ if (answer == IsArrayAnswer::RevokedProxy) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_PROXY_REVOKED);
+ return false;
+ }
+
+ *isArray = answer == IsArrayAnswer::Array;
+ return true;
+}
+
+bool js::IsArrayFromJit(JSContext* cx, HandleObject obj, bool* isArray) {
+ return JS::IsArray(cx, obj, isArray);
+}
+
+// ES2017 7.1.15 ToLength, but clamped to the [0,2^32-2] range.
+static bool ToLengthClamped(JSContext* cx, HandleValue v, uint32_t* out) {
+ if (v.isInt32()) {
+ int32_t i = v.toInt32();
+ *out = i < 0 ? 0 : i;
+ return true;
+ }
+ double d;
+ if (v.isDouble()) {
+ d = v.toDouble();
+ } else {
+ if (!ToNumber(cx, v, &d)) {
+ return false;
+ }
+ }
+ d = JS::ToInteger(d);
+ if (d <= 0.0) {
+ *out = 0;
+ } else if (d < double(UINT32_MAX - 1)) {
+ *out = uint32_t(d);
+ } else {
+ *out = UINT32_MAX;
+ }
+ return true;
+}
+
+bool js::GetLengthProperty(JSContext* cx, HandleObject obj, uint32_t* lengthp) {
+ if (obj->is<ArrayObject>()) {
+ *lengthp = obj->as<ArrayObject>().length();
+ return true;
+ }
+
+ if (obj->is<ArgumentsObject>()) {
+ ArgumentsObject& argsobj = obj->as<ArgumentsObject>();
+ if (!argsobj.hasOverriddenLength()) {
+ *lengthp = argsobj.initialLength();
+ return true;
+ }
+ }
+
+ RootedValue value(cx);
+ if (!GetProperty(cx, obj, obj, cx->names().length, &value)) {
+ return false;
+ }
+
+ if (!ToLengthClamped(cx, value, lengthp)) {
+ return false;
+ }
+
+ return true;
+}
+
+// ES2017 7.1.15 ToLength.
+bool js::ToLength(JSContext* cx, HandleValue v, uint64_t* out) {
+ if (v.isInt32()) {
+ int32_t i = v.toInt32();
+ *out = i < 0 ? 0 : i;
+ return true;
+ }
+
+ double d;
+ if (v.isDouble()) {
+ d = v.toDouble();
+ } else {
+ if (!ToNumber(cx, v, &d)) {
+ return false;
+ }
+ }
+
+ d = JS::ToInteger(d);
+ if (d <= 0.0) {
+ *out = 0;
+ } else {
+ *out = uint64_t(std::min(d, DOUBLE_INTEGRAL_PRECISION_LIMIT - 1));
+ }
+ return true;
+}
+
+static MOZ_ALWAYS_INLINE bool GetLengthProperty(JSContext* cx, HandleObject obj,
+ uint64_t* lengthp) {
+ if (obj->is<ArrayObject>()) {
+ *lengthp = obj->as<ArrayObject>().length();
+ return true;
+ }
+
+ if (obj->is<ArgumentsObject>()) {
+ ArgumentsObject& argsobj = obj->as<ArgumentsObject>();
+ if (!argsobj.hasOverriddenLength()) {
+ *lengthp = argsobj.initialLength();
+ return true;
+ }
+ }
+
+ RootedValue value(cx);
+ if (!GetProperty(cx, obj, obj, cx->names().length, &value)) {
+ return false;
+ }
+
+ return ToLength(cx, value, lengthp);
+}
+
+/*
+ * Determine if the id represents an array index.
+ *
+ * An id is an array index according to ECMA by (15.4):
+ *
+ * "Array objects give special treatment to a certain class of property names.
+ * A property name P (in the form of a string value) is an array index if and
+ * only if ToString(ToUint32(P)) is equal to P and ToUint32(P) is not equal
+ * to 2^32-1."
+ *
+ * This means the largest allowed index is actually 2^32-2 (4294967294).
+ *
+ * In our implementation, it would be sufficient to check for id.isInt32()
+ * except that by using signed 31-bit integers we miss the top half of the
+ * valid range. This function checks the string representation itself; note
+ * that calling a standard conversion routine might allow strings such as
+ * "08" or "4.0" as array indices, which they are not.
+ *
+ */
+template <typename CharT>
+static bool StringIsArrayIndexHelper(const CharT* s, uint32_t length,
+ uint32_t* indexp) {
+ const CharT* end = s + length;
+
+ if (length == 0 || length > (sizeof("4294967294") - 1) || !IsAsciiDigit(*s)) {
+ return false;
+ }
+
+ uint32_t c = 0, previous = 0;
+ uint32_t index = AsciiDigitToNumber(*s++);
+
+ /* Don't allow leading zeros. */
+ if (index == 0 && s != end) {
+ return false;
+ }
+
+ for (; s < end; s++) {
+ if (!IsAsciiDigit(*s)) {
+ return false;
+ }
+
+ previous = index;
+ c = AsciiDigitToNumber(*s);
+ index = 10 * index + c;
+ }
+
+ /* Make sure we didn't overflow. */
+ if (previous < (MAX_ARRAY_INDEX / 10) ||
+ (previous == (MAX_ARRAY_INDEX / 10) && c <= (MAX_ARRAY_INDEX % 10))) {
+ MOZ_ASSERT(index <= MAX_ARRAY_INDEX);
+ *indexp = index;
+ return true;
+ }
+
+ return false;
+}
+
+JS_FRIEND_API bool js::StringIsArrayIndex(JSLinearString* str,
+ uint32_t* indexp) {
+ AutoCheckCannotGC nogc;
+ return str->hasLatin1Chars()
+ ? StringIsArrayIndexHelper(str->latin1Chars(nogc), str->length(),
+ indexp)
+ : StringIsArrayIndexHelper(str->twoByteChars(nogc), str->length(),
+ indexp);
+}
+
+JS_FRIEND_API bool js::StringIsArrayIndex(const char16_t* str, uint32_t length,
+ uint32_t* indexp) {
+ return StringIsArrayIndexHelper(str, length, indexp);
+}
+
+template <typename T>
+static bool ToId(JSContext* cx, T index, MutableHandleId id);
+
+template <>
+bool ToId(JSContext* cx, uint32_t index, MutableHandleId id) {
+ return IndexToId(cx, index, id);
+}
+
+template <>
+bool ToId(JSContext* cx, uint64_t index, MutableHandleId id) {
+ MOZ_ASSERT(index < uint64_t(DOUBLE_INTEGRAL_PRECISION_LIMIT));
+
+ if (index == uint32_t(index)) {
+ return IndexToId(cx, uint32_t(index), id);
+ }
+
+ Value tmp = DoubleValue(index);
+ return PrimitiveValueToId<CanGC>(cx, HandleValue::fromMarkedLocation(&tmp),
+ id);
+}
+
+/*
+ * If the property at the given index exists, get its value into |vp| and set
+ * |*hole| to false. Otherwise set |*hole| to true and |vp| to Undefined.
+ */
+template <typename T>
+static bool HasAndGetElement(JSContext* cx, HandleObject obj,
+ HandleObject receiver, T index, bool* hole,
+ MutableHandleValue vp) {
+ if (obj->isNative()) {
+ NativeObject* nobj = &obj->as<NativeObject>();
+ if (index < nobj->getDenseInitializedLength()) {
+ vp.set(nobj->getDenseElement(size_t(index)));
+ if (!vp.isMagic(JS_ELEMENTS_HOLE)) {
+ *hole = false;
+ return true;
+ }
+ }
+ if (nobj->is<ArgumentsObject>() && index <= UINT32_MAX) {
+ if (nobj->as<ArgumentsObject>().maybeGetElement(uint32_t(index), vp)) {
+ *hole = false;
+ return true;
+ }
+ }
+ }
+
+ RootedId id(cx);
+ if (!ToId(cx, index, &id)) {
+ return false;
+ }
+
+ bool found;
+ if (!HasProperty(cx, obj, id, &found)) {
+ return false;
+ }
+
+ if (found) {
+ if (!GetProperty(cx, obj, receiver, id, vp)) {
+ return false;
+ }
+ } else {
+ vp.setUndefined();
+ }
+ *hole = !found;
+ return true;
+}
+
+template <typename T>
+static inline bool HasAndGetElement(JSContext* cx, HandleObject obj, T index,
+ bool* hole, MutableHandleValue vp) {
+ return HasAndGetElement(cx, obj, obj, index, hole, vp);
+}
+
+bool ElementAdder::append(JSContext* cx, HandleValue v) {
+ MOZ_ASSERT(index_ < length_);
+ if (resObj_) {
+ NativeObject* resObj = &resObj_->as<NativeObject>();
+ DenseElementResult result =
+ resObj->setOrExtendDenseElements(cx, index_, v.address(), 1);
+ if (result == DenseElementResult::Failure) {
+ return false;
+ }
+ if (result == DenseElementResult::Incomplete) {
+ if (!DefineDataElement(cx, resObj_, index_, v)) {
+ return false;
+ }
+ }
+ } else {
+ vp_[index_] = v;
+ }
+ index_++;
+ return true;
+}
+
+void ElementAdder::appendHole() {
+ MOZ_ASSERT(getBehavior_ == ElementAdder::CheckHasElemPreserveHoles);
+ MOZ_ASSERT(index_ < length_);
+ if (!resObj_) {
+ vp_[index_].setMagic(JS_ELEMENTS_HOLE);
+ }
+ index_++;
+}
+
+bool js::GetElementsWithAdder(JSContext* cx, HandleObject obj,
+ HandleObject receiver, uint32_t begin,
+ uint32_t end, ElementAdder* adder) {
+ MOZ_ASSERT(begin <= end);
+
+ RootedValue val(cx);
+ for (uint32_t i = begin; i < end; i++) {
+ if (adder->getBehavior() == ElementAdder::CheckHasElemPreserveHoles) {
+ bool hole;
+ if (!HasAndGetElement(cx, obj, receiver, i, &hole, &val)) {
+ return false;
+ }
+ if (hole) {
+ adder->appendHole();
+ continue;
+ }
+ } else {
+ MOZ_ASSERT(adder->getBehavior() == ElementAdder::GetElement);
+ if (!GetElement(cx, obj, receiver, i, &val)) {
+ return false;
+ }
+ }
+ if (!adder->append(cx, val)) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static inline bool IsPackedArrayOrNoExtraIndexedProperties(JSObject* obj,
+ uint64_t length) {
+ return (IsPackedArray(obj) && obj->as<ArrayObject>().length() == length) ||
+ !ObjectMayHaveExtraIndexedProperties(obj);
+}
+
+static bool GetDenseElements(NativeObject* aobj, uint32_t length, Value* vp) {
+ MOZ_ASSERT(IsPackedArrayOrNoExtraIndexedProperties(aobj, length));
+
+ if (length > aobj->getDenseInitializedLength()) {
+ return false;
+ }
+
+ for (size_t i = 0; i < length; i++) {
+ vp[i] = aobj->getDenseElement(i);
+
+ // No other indexed properties so hole => undefined.
+ if (vp[i].isMagic(JS_ELEMENTS_HOLE)) {
+ vp[i] = UndefinedValue();
+ }
+ }
+
+ return true;
+}
+
+bool js::GetElements(JSContext* cx, HandleObject aobj, uint32_t length,
+ Value* vp) {
+ if (IsPackedArrayOrNoExtraIndexedProperties(aobj, length)) {
+ if (GetDenseElements(&aobj->as<NativeObject>(), length, vp)) {
+ return true;
+ }
+ }
+
+ if (aobj->is<ArgumentsObject>()) {
+ ArgumentsObject& argsobj = aobj->as<ArgumentsObject>();
+ if (!argsobj.hasOverriddenLength()) {
+ if (argsobj.maybeGetElements(0, length, vp)) {
+ return true;
+ }
+ }
+ }
+
+ if (aobj->is<TypedArrayObject>()) {
+ Handle<TypedArrayObject*> typedArray = aobj.as<TypedArrayObject>();
+ if (typedArray->length().get() == length) {
+ return TypedArrayObject::getElements(cx, typedArray, vp);
+ }
+ }
+
+ if (js::GetElementsOp op = aobj->getOpsGetElements()) {
+ ElementAdder adder(cx, vp, length, ElementAdder::GetElement);
+ return op(cx, aobj, 0, length, &adder);
+ }
+
+ for (uint32_t i = 0; i < length; i++) {
+ if (!GetElement(cx, aobj, aobj, i,
+ MutableHandleValue::fromMarkedLocation(&vp[i]))) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static inline bool GetArrayElement(JSContext* cx, HandleObject obj,
+ uint64_t index, MutableHandleValue vp) {
+ if (obj->isNative()) {
+ NativeObject* nobj = &obj->as<NativeObject>();
+ if (index < nobj->getDenseInitializedLength()) {
+ vp.set(nobj->getDenseElement(size_t(index)));
+ if (!vp.isMagic(JS_ELEMENTS_HOLE)) {
+ return true;
+ }
+ }
+
+ if (nobj->is<ArgumentsObject>() && index <= UINT32_MAX) {
+ if (nobj->as<ArgumentsObject>().maybeGetElement(uint32_t(index), vp)) {
+ return true;
+ }
+ }
+ }
+
+ RootedId id(cx);
+ if (!ToId(cx, index, &id)) {
+ return false;
+ }
+ return GetProperty(cx, obj, obj, id, vp);
+}
+
+static inline bool DefineArrayElement(JSContext* cx, HandleObject obj,
+ uint64_t index, HandleValue value) {
+ RootedId id(cx);
+ if (!ToId(cx, index, &id)) {
+ return false;
+ }
+ return DefineDataProperty(cx, obj, id, value);
+}
+
+// Set the value of the property at the given index to v.
+static inline bool SetArrayElement(JSContext* cx, HandleObject obj,
+ uint64_t index, HandleValue v) {
+ RootedId id(cx);
+ if (!ToId(cx, index, &id)) {
+ return false;
+ }
+
+ return SetProperty(cx, obj, id, v);
+}
+
+/*
+ * Attempt to delete the element |index| from |obj| as if by
+ * |obj.[[Delete]](index)|.
+ *
+ * If an error occurs while attempting to delete the element (that is, the call
+ * to [[Delete]] threw), return false.
+ *
+ * Otherwise call result.succeed() or result.fail() to indicate whether the
+ * deletion attempt succeeded (that is, whether the call to [[Delete]] returned
+ * true or false). (Deletes generally fail only when the property is
+ * non-configurable, but proxies may implement different semantics.)
+ */
+static bool DeleteArrayElement(JSContext* cx, HandleObject obj, uint64_t index,
+ ObjectOpResult& result) {
+ if (obj->is<ArrayObject>() && !obj->as<NativeObject>().isIndexed() &&
+ !obj->as<NativeObject>().denseElementsAreSealed()) {
+ ArrayObject* aobj = &obj->as<ArrayObject>();
+ if (index <= UINT32_MAX) {
+ uint32_t idx = uint32_t(index);
+ if (idx < aobj->getDenseInitializedLength()) {
+ if (idx + 1 == aobj->getDenseInitializedLength()) {
+ aobj->setDenseInitializedLengthMaybeNonExtensible(cx, idx);
+ } else {
+ aobj->setDenseElementHole(idx);
+ }
+ if (!SuppressDeletedElement(cx, obj, idx)) {
+ return false;
+ }
+ }
+ }
+
+ return result.succeed();
+ }
+
+ RootedId id(cx);
+ if (!ToId(cx, index, &id)) {
+ return false;
+ }
+ return DeleteProperty(cx, obj, id, result);
+}
+
+/* ES6 draft rev 32 (2 Febr 2015) 7.3.7 */
+static bool DeletePropertyOrThrow(JSContext* cx, HandleObject obj,
+ uint64_t index) {
+ ObjectOpResult success;
+ if (!DeleteArrayElement(cx, obj, index, success)) {
+ return false;
+ }
+ if (!success) {
+ RootedId id(cx);
+ if (!ToId(cx, index, &id)) {
+ return false;
+ }
+ return success.reportError(cx, obj, id);
+ }
+ return true;
+}
+
+static bool DeletePropertiesOrThrow(JSContext* cx, HandleObject obj,
+ uint64_t len, uint64_t finalLength) {
+ if (obj->is<ArrayObject>() && !obj->as<NativeObject>().isIndexed() &&
+ !obj->as<NativeObject>().denseElementsAreSealed()) {
+ if (len <= UINT32_MAX) {
+ // Skip forward to the initialized elements of this array.
+ len = std::min(uint32_t(len),
+ obj->as<ArrayObject>().getDenseInitializedLength());
+ }
+ }
+
+ for (uint64_t k = len; k > finalLength; k--) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ if (!DeletePropertyOrThrow(cx, obj, k - 1)) {
+ return false;
+ }
+ }
+ return true;
+}
+
+static bool SetArrayLengthProperty(JSContext* cx, HandleArrayObject obj,
+ HandleValue value) {
+ RootedId id(cx, NameToId(cx->names().length));
+ ObjectOpResult result;
+ if (obj->lengthIsWritable()) {
+ if (!ArraySetLength(cx, obj, id, JSPROP_PERMANENT, value, result)) {
+ return false;
+ }
+ } else {
+ MOZ_ALWAYS_TRUE(result.fail(JSMSG_READ_ONLY));
+ }
+ return result.checkStrict(cx, obj, id);
+}
+
+static bool SetLengthProperty(JSContext* cx, HandleObject obj,
+ uint64_t length) {
+ MOZ_ASSERT(length < uint64_t(DOUBLE_INTEGRAL_PRECISION_LIMIT));
+
+ RootedValue v(cx, NumberValue(length));
+ if (obj->is<ArrayObject>()) {
+ return SetArrayLengthProperty(cx, obj.as<ArrayObject>(), v);
+ }
+ return SetProperty(cx, obj, cx->names().length, v);
+}
+
+bool js::SetLengthProperty(JSContext* cx, HandleObject obj, uint32_t length) {
+ RootedValue v(cx, NumberValue(length));
+ if (obj->is<ArrayObject>()) {
+ return SetArrayLengthProperty(cx, obj.as<ArrayObject>(), v);
+ }
+ return SetProperty(cx, obj, cx->names().length, v);
+}
+
+static bool array_length_getter(JSContext* cx, HandleObject obj, HandleId id,
+ MutableHandleValue vp) {
+ vp.setNumber(obj->as<ArrayObject>().length());
+ return true;
+}
+
+static bool array_length_setter(JSContext* cx, HandleObject obj, HandleId id,
+ HandleValue v, ObjectOpResult& result) {
+ MOZ_ASSERT(id == NameToId(cx->names().length));
+
+ if (!obj->is<ArrayObject>()) {
+ // This array .length property was found on the prototype
+ // chain. Ideally the setter should not have been called, but since
+ // we're here, do an impression of SetPropertyByDefining.
+ return DefineDataProperty(cx, obj, id, v, JSPROP_ENUMERATE, result);
+ }
+
+ HandleArrayObject arr = obj.as<ArrayObject>();
+ MOZ_ASSERT(arr->lengthIsWritable(),
+ "setter shouldn't be called if property is non-writable");
+
+ return ArraySetLength(cx, arr, id, JSPROP_PERMANENT, v, result);
+}
+
+struct ReverseIndexComparator {
+ bool operator()(const uint32_t& a, const uint32_t& b, bool* lessOrEqualp) {
+ MOZ_ASSERT(a != b, "how'd we get duplicate indexes?");
+ *lessOrEqualp = b <= a;
+ return true;
+ }
+};
+
+/* ES6 draft rev 34 (2015 Feb 20) 9.4.2.4 ArraySetLength */
+bool js::ArraySetLength(JSContext* cx, Handle<ArrayObject*> arr, HandleId id,
+ unsigned attrs, HandleValue value,
+ ObjectOpResult& result) {
+ MOZ_ASSERT(id == NameToId(cx->names().length));
+
+ // Step 1.
+ uint32_t newLen;
+ if (attrs & JSPROP_IGNORE_VALUE) {
+ MOZ_ASSERT(value.isUndefined());
+
+ // The spec has us calling OrdinaryDefineOwnProperty if
+ // Desc.[[Value]] is absent, but our implementation is so different that
+ // this is impossible. Instead, set newLen to the current length and
+ // proceed to step 9.
+ newLen = arr->length();
+ } else {
+ // Step 2 is irrelevant in our implementation.
+
+ // Step 3.
+ if (!ToUint32(cx, value, &newLen)) {
+ return false;
+ }
+
+ // Step 4.
+ double d;
+ if (!ToNumber(cx, value, &d)) {
+ return false;
+ }
+
+ // Step 5.
+ if (d != newLen) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_BAD_ARRAY_LENGTH);
+ return false;
+ }
+
+ // Steps 6-8 are irrelevant in our implementation.
+ }
+
+ // Steps 9-11.
+ bool lengthIsWritable = arr->lengthIsWritable();
+#ifdef DEBUG
+ {
+ RootedShape lengthShape(cx, arr->lookupPure(id));
+ MOZ_ASSERT(lengthShape);
+ MOZ_ASSERT(lengthShape->writable() == lengthIsWritable);
+ }
+#endif
+ uint32_t oldLen = arr->length();
+
+ // Part of steps 1.a, 12.a, and 16: Fail if we're being asked to change
+ // enumerability or configurability, or otherwise break the object
+ // invariants. (ES6 checks these by calling OrdinaryDefineOwnProperty, but
+ // in SM, the array length property is hardly ordinary.)
+ if ((attrs & (JSPROP_PERMANENT | JSPROP_IGNORE_PERMANENT)) == 0 ||
+ (attrs & (JSPROP_ENUMERATE | JSPROP_IGNORE_ENUMERATE)) ==
+ JSPROP_ENUMERATE ||
+ (attrs & (JSPROP_GETTER | JSPROP_SETTER)) != 0 ||
+ (!lengthIsWritable &&
+ (attrs & (JSPROP_READONLY | JSPROP_IGNORE_READONLY)) == 0)) {
+ return result.fail(JSMSG_CANT_REDEFINE_PROP);
+ }
+
+ // Steps 12-13 for arrays with non-writable length.
+ if (!lengthIsWritable) {
+ if (newLen == oldLen) {
+ return result.succeed();
+ }
+
+ return result.fail(JSMSG_CANT_REDEFINE_ARRAY_LENGTH);
+ }
+
+ // Step 19.
+ bool succeeded = true;
+ do {
+ // The initialized length and capacity of an array only need updating
+ // when non-hole elements are added or removed, which doesn't happen
+ // when array length stays the same or increases.
+ if (newLen >= oldLen) {
+ break;
+ }
+
+ // Attempt to propagate dense-element optimization tricks, if possible,
+ // and avoid the generic (and accordingly slow) deletion code below.
+ // We can only do this if there are only densely-indexed elements.
+ // Once there's a sparse indexed element, there's no good way to know,
+ // save by enumerating all the properties to find it. But we *have* to
+ // know in case that sparse indexed element is non-configurable, as
+ // that element must prevent any deletions below it. Bug 586842 should
+ // fix this inefficiency by moving indexed storage to be entirely
+ // separate from non-indexed storage.
+ // A second reason for this optimization to be invalid is an active
+ // for..in iteration over the array. Keys deleted before being reached
+ // during the iteration must not be visited, and suppressing them here
+ // would be too costly.
+ // This optimization is also invalid when there are sealed
+ // (non-configurable) elements.
+ if (!arr->isIndexed() && !arr->denseElementsMaybeInIteration() &&
+ !arr->denseElementsAreSealed()) {
+ uint32_t oldCapacity = arr->getDenseCapacity();
+ uint32_t oldInitializedLength = arr->getDenseInitializedLength();
+ MOZ_ASSERT(oldCapacity >= oldInitializedLength);
+ if (oldInitializedLength > newLen) {
+ arr->setDenseInitializedLengthMaybeNonExtensible(cx, newLen);
+ }
+ if (oldCapacity > newLen) {
+ if (arr->isExtensible()) {
+ arr->shrinkElements(cx, newLen);
+ } else {
+ MOZ_ASSERT(arr->getDenseInitializedLength() ==
+ arr->getDenseCapacity());
+ }
+ }
+
+ // We've done the work of deleting any dense elements needing
+ // deletion, and there are no sparse elements. Thus we can skip
+ // straight to defining the length.
+ break;
+ }
+
+ // Step 15.
+ //
+ // Attempt to delete all elements above the new length, from greatest
+ // to least. If any of these deletions fails, we're supposed to define
+ // the length to one greater than the index that couldn't be deleted,
+ // *with the property attributes specified*. This might convert the
+ // length to be not the value specified, yet non-writable. (You may be
+ // forgiven for thinking these are interesting semantics.) Example:
+ //
+ // var arr =
+ // Object.defineProperty([0, 1, 2, 3], 1, { writable: false });
+ // Object.defineProperty(arr, "length",
+ // { value: 0, writable: false });
+ //
+ // will convert |arr| to an array of non-writable length two, then
+ // throw a TypeError.
+ //
+ // We implement this behavior, in the relevant lops below, by setting
+ // |succeeded| to false. Then we exit the loop, define the length
+ // appropriately, and only then throw a TypeError, if necessary.
+ uint32_t gap = oldLen - newLen;
+ const uint32_t RemoveElementsFastLimit = 1 << 24;
+ if (gap < RemoveElementsFastLimit) {
+ // If we're removing a relatively small number of elements, just do
+ // it exactly by the spec.
+ while (newLen < oldLen) {
+ // Step 15a.
+ oldLen--;
+
+ // Steps 15b-d.
+ ObjectOpResult deleteSucceeded;
+ if (!DeleteElement(cx, arr, oldLen, deleteSucceeded)) {
+ return false;
+ }
+ if (!deleteSucceeded) {
+ newLen = oldLen + 1;
+ succeeded = false;
+ break;
+ }
+ }
+ } else {
+ // If we're removing a large number of elements from an array
+ // that's probably sparse, try a different tack. Get all the own
+ // property names, sift out the indexes in the deletion range into
+ // a vector, sort the vector greatest to least, then delete the
+ // indexes greatest to least using that vector. See bug 322135.
+ //
+ // This heuristic's kind of a huge guess -- "large number of
+ // elements" and "probably sparse" are completely unprincipled
+ // predictions. In the long run, bug 586842 will support the right
+ // fix: store sparse elements in a sorted data structure that
+ // permits fast in-reverse-order traversal and concurrent removals.
+
+ Vector<uint32_t> indexes(cx);
+ {
+ RootedIdVector props(cx);
+ if (!GetPropertyKeys(cx, arr, JSITER_OWNONLY | JSITER_HIDDEN, &props)) {
+ return false;
+ }
+
+ for (size_t i = 0; i < props.length(); i++) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ uint32_t index;
+ if (!IdIsIndex(props[i], &index)) {
+ continue;
+ }
+
+ if (index >= newLen && index < oldLen) {
+ if (!indexes.append(index)) {
+ return false;
+ }
+ }
+ }
+ }
+
+ uint32_t count = indexes.length();
+ {
+ // We should use radix sort to be O(n), but this is uncommon
+ // enough that we'll punt til someone complains.
+ Vector<uint32_t> scratch(cx);
+ if (!scratch.resize(count)) {
+ return false;
+ }
+ MOZ_ALWAYS_TRUE(MergeSort(indexes.begin(), count, scratch.begin(),
+ ReverseIndexComparator()));
+ }
+
+ uint32_t index = UINT32_MAX;
+ for (uint32_t i = 0; i < count; i++) {
+ MOZ_ASSERT(indexes[i] < index, "indexes should never repeat");
+ index = indexes[i];
+
+ // Steps 15b-d.
+ ObjectOpResult deleteSucceeded;
+ if (!DeleteElement(cx, arr, index, deleteSucceeded)) {
+ return false;
+ }
+ if (!deleteSucceeded) {
+ newLen = index + 1;
+ succeeded = false;
+ break;
+ }
+ }
+ }
+ } while (false);
+
+ // Update array length. Technically we should have been doing this
+ // throughout the loop, in step 19.d.iii.
+ arr->setLength(newLen);
+
+ // Step 20.
+ if (attrs & JSPROP_READONLY) {
+ // Yes, we totally drop a non-stub getter/setter from a defineProperty
+ // API call on the floor here. Given that getter/setter will go away in
+ // the long run, with accessors replacing them both internally and at the
+ // API level, just run with this.
+ RootedShape lengthShape(cx, arr->lookup(cx, id));
+ if (!NativeObject::changeProperty(
+ cx, arr, lengthShape, lengthShape->attributes() | JSPROP_READONLY,
+ array_length_getter, array_length_setter)) {
+ return false;
+ }
+ }
+
+ // All operations past here until the |!succeeded| code must be infallible,
+ // so that all element fields remain properly synchronized.
+
+ // Trim the initialized length, if needed, to preserve the <= length
+ // invariant. (Capacity was already reduced during element deletion, if
+ // necessary.)
+ ObjectElements* header = arr->getElementsHeader();
+ header->initializedLength = std::min(header->initializedLength, newLen);
+
+ if (!arr->isExtensible()) {
+ arr->shrinkCapacityToInitializedLength(cx);
+ }
+
+ if (attrs & JSPROP_READONLY) {
+ arr->setNonWritableLength(cx);
+ }
+
+ if (!succeeded) {
+ return result.fail(JSMSG_CANT_TRUNCATE_ARRAY);
+ }
+
+ return result.succeed();
+}
+
+static bool array_addProperty(JSContext* cx, HandleObject obj, HandleId id,
+ HandleValue v) {
+ ArrayObject* arr = &obj->as<ArrayObject>();
+
+ uint32_t index;
+ if (!IdIsIndex(id, &index)) {
+ return true;
+ }
+
+ uint32_t length = arr->length();
+ if (index >= length) {
+ MOZ_ASSERT(arr->lengthIsWritable(),
+ "how'd this element get added if length is non-writable?");
+ arr->setLength(index + 1);
+ }
+ return true;
+}
+
+static inline bool ObjectMayHaveExtraIndexedOwnProperties(JSObject* obj) {
+ if (!obj->isNative()) {
+ return true;
+ }
+
+ if (obj->as<NativeObject>().isIndexed()) {
+ return true;
+ }
+
+ if (obj->is<TypedArrayObject>()) {
+ return true;
+ }
+
+ return ClassMayResolveId(*obj->runtimeFromAnyThread()->commonNames,
+ obj->getClass(), INT_TO_JSID(0), obj);
+}
+
+/*
+ * Whether obj may have indexed properties anywhere besides its dense
+ * elements. This includes other indexed properties in its shape hierarchy, and
+ * indexed properties or elements along its prototype chain.
+ */
+bool js::ObjectMayHaveExtraIndexedProperties(JSObject* obj) {
+ MOZ_ASSERT_IF(obj->hasDynamicPrototype(), !obj->isNative());
+
+ if (ObjectMayHaveExtraIndexedOwnProperties(obj)) {
+ return true;
+ }
+
+ do {
+ MOZ_ASSERT(obj->hasStaticPrototype(),
+ "dynamic-prototype objects must be non-native, ergo must "
+ "have failed ObjectMayHaveExtraIndexedOwnProperties");
+
+ obj = obj->staticPrototype();
+ if (!obj) {
+ return false; // no extra indexed properties found
+ }
+
+ if (ObjectMayHaveExtraIndexedOwnProperties(obj)) {
+ return true;
+ }
+ if (obj->as<NativeObject>().getDenseInitializedLength() != 0) {
+ return true;
+ }
+ } while (true);
+}
+
+static bool AddLengthProperty(JSContext* cx, HandleArrayObject obj) {
+ // Add the 'length' property for a newly created array. Shapes are shared
+ // across realms within a zone and because we update the initial shape with
+ // a Shape that contains the length-property (in NewArray), it's possible
+ // the length property has already been defined.
+
+ Shape* shape = obj->lastProperty();
+ if (!shape->isEmptyShape()) {
+ MOZ_ASSERT(JSID_IS_ATOM(shape->propidRaw(), cx->names().length));
+ MOZ_ASSERT(shape->previous()->isEmptyShape());
+ return true;
+ }
+
+ RootedId lengthId(cx, NameToId(cx->names().length));
+ return NativeObject::addAccessorProperty(
+ cx, obj, lengthId, array_length_getter, array_length_setter,
+ JSPROP_PERMANENT);
+}
+
+static bool IsArrayConstructor(const JSObject* obj) {
+ // Note: this also returns true for cross-realm Array constructors in the
+ // same compartment.
+ return IsNativeFunction(obj, ArrayConstructor);
+}
+
+static bool IsArrayConstructor(const Value& v) {
+ return v.isObject() && IsArrayConstructor(&v.toObject());
+}
+
+bool js::IsCrossRealmArrayConstructor(JSContext* cx, JSObject* obj,
+ bool* result) {
+ if (obj->is<WrapperObject>()) {
+ obj = CheckedUnwrapDynamic(obj, cx);
+ if (!obj) {
+ ReportAccessDenied(cx);
+ return false;
+ }
+ }
+
+ *result =
+ IsArrayConstructor(obj) && obj->as<JSFunction>().realm() != cx->realm();
+ return true;
+}
+
+static MOZ_ALWAYS_INLINE bool IsArraySpecies(JSContext* cx,
+ HandleObject origArray) {
+ if (MOZ_UNLIKELY(origArray->is<ProxyObject>())) {
+ if (origArray->getClass()->isDOMClass()) {
+#ifdef DEBUG
+ // We assume DOM proxies never return true for IsArray.
+ IsArrayAnswer answer;
+ MOZ_ASSERT(Proxy::isArray(cx, origArray, &answer));
+ MOZ_ASSERT(answer == IsArrayAnswer::NotArray);
+#endif
+ return true;
+ }
+ return false;
+ }
+
+ // 9.4.2.3 Step 4. Non-array objects always use the default constructor.
+ if (!origArray->is<ArrayObject>()) {
+ return true;
+ }
+
+ if (cx->realm()->arraySpeciesLookup.tryOptimizeArray(
+ cx, &origArray->as<ArrayObject>())) {
+ return true;
+ }
+
+ Value ctor;
+ if (!GetPropertyPure(cx, origArray, NameToId(cx->names().constructor),
+ &ctor)) {
+ return false;
+ }
+
+ if (!IsArrayConstructor(ctor)) {
+ return ctor.isUndefined();
+ }
+
+ // 9.4.2.3 Step 6.c. Use the current realm's constructor if |ctor| is a
+ // cross-realm Array constructor.
+ if (cx->realm() != ctor.toObject().as<JSFunction>().realm()) {
+ return true;
+ }
+
+ jsid speciesId = SYMBOL_TO_JSID(cx->wellKnownSymbols().species);
+ JSFunction* getter;
+ if (!GetGetterPure(cx, &ctor.toObject(), speciesId, &getter)) {
+ return false;
+ }
+
+ if (!getter) {
+ return false;
+ }
+
+ return IsSelfHostedFunctionWithName(getter, cx->names().ArraySpecies);
+}
+
+static bool ArraySpeciesCreate(JSContext* cx, HandleObject origArray,
+ uint64_t length, MutableHandleObject arr) {
+ MOZ_ASSERT(length < DOUBLE_INTEGRAL_PRECISION_LIMIT);
+
+ FixedInvokeArgs<2> args(cx);
+
+ args[0].setObject(*origArray);
+ args[1].set(NumberValue(length));
+
+ RootedValue rval(cx);
+ if (!CallSelfHostedFunction(cx, cx->names().ArraySpeciesCreate,
+ UndefinedHandleValue, args, &rval)) {
+ return false;
+ }
+
+ MOZ_ASSERT(rval.isObject());
+ arr.set(&rval.toObject());
+ return true;
+}
+
+JSString* js::ArrayToSource(JSContext* cx, HandleObject obj) {
+ AutoCycleDetector detector(cx, obj);
+ if (!detector.init()) {
+ return nullptr;
+ }
+
+ JSStringBuilder sb(cx);
+
+ if (detector.foundCycle()) {
+ if (!sb.append("[]")) {
+ return nullptr;
+ }
+ return sb.finishString();
+ }
+
+ if (!sb.append('[')) {
+ return nullptr;
+ }
+
+ uint64_t length;
+ if (!GetLengthProperty(cx, obj, &length)) {
+ return nullptr;
+ }
+
+ RootedValue elt(cx);
+ for (uint64_t index = 0; index < length; index++) {
+ bool hole;
+ if (!CheckForInterrupt(cx) ||
+ !HasAndGetElement(cx, obj, index, &hole, &elt)) {
+ return nullptr;
+ }
+
+ /* Get element's character string. */
+ JSString* str;
+ if (hole) {
+ str = cx->runtime()->emptyString;
+ } else {
+ str = ValueToSource(cx, elt);
+ if (!str) {
+ return nullptr;
+ }
+ }
+
+ /* Append element to buffer. */
+ if (!sb.append(str)) {
+ return nullptr;
+ }
+ if (index + 1 != length) {
+ if (!sb.append(", ")) {
+ return nullptr;
+ }
+ } else if (hole) {
+ if (!sb.append(',')) {
+ return nullptr;
+ }
+ }
+ }
+
+ /* Finalize the buffer. */
+ if (!sb.append(']')) {
+ return nullptr;
+ }
+
+ return sb.finishString();
+}
+
+static bool array_toSource(JSContext* cx, unsigned argc, Value* vp) {
+ if (!CheckRecursionLimit(cx)) {
+ return false;
+ }
+
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ if (!args.thisv().isObject()) {
+ ReportIncompatible(cx, args);
+ return false;
+ }
+
+ Rooted<JSObject*> obj(cx, &args.thisv().toObject());
+
+ JSString* str = ArrayToSource(cx, obj);
+ if (!str) {
+ return false;
+ }
+
+ args.rval().setString(str);
+ return true;
+}
+
+struct EmptySeparatorOp {
+ bool operator()(JSContext*, StringBuffer& sb) { return true; }
+};
+
+template <typename CharT>
+struct CharSeparatorOp {
+ const CharT sep;
+ explicit CharSeparatorOp(CharT sep) : sep(sep) {}
+ bool operator()(JSContext*, StringBuffer& sb) { return sb.append(sep); }
+};
+
+struct StringSeparatorOp {
+ HandleLinearString sep;
+
+ explicit StringSeparatorOp(HandleLinearString sep) : sep(sep) {}
+
+ bool operator()(JSContext* cx, StringBuffer& sb) { return sb.append(sep); }
+};
+
+template <typename SeparatorOp>
+static bool ArrayJoinDenseKernel(JSContext* cx, SeparatorOp sepOp,
+ HandleNativeObject obj, uint64_t length,
+ StringBuffer& sb, uint32_t* numProcessed) {
+ // This loop handles all elements up to initializedLength. If
+ // length > initLength we rely on the second loop to add the
+ // other elements.
+ MOZ_ASSERT(*numProcessed == 0);
+ uint64_t initLength =
+ std::min<uint64_t>(obj->getDenseInitializedLength(), length);
+ MOZ_ASSERT(initLength <= UINT32_MAX,
+ "initialized length shouldn't exceed UINT32_MAX");
+ uint32_t initLengthClamped = uint32_t(initLength);
+ while (*numProcessed < initLengthClamped) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ // Step 7.b.
+ Value elem = obj->getDenseElement(*numProcessed);
+
+ // Steps 7.c-d.
+ if (elem.isString()) {
+ if (!sb.append(elem.toString())) {
+ return false;
+ }
+ } else if (elem.isNumber()) {
+ if (!NumberValueToStringBuffer(cx, elem, sb)) {
+ return false;
+ }
+ } else if (elem.isBoolean()) {
+ if (!BooleanToStringBuffer(elem.toBoolean(), sb)) {
+ return false;
+ }
+ } else if (elem.isObject() || elem.isSymbol()) {
+ /*
+ * Object stringifying could modify the initialized length or make
+ * the array sparse. Delegate it to a separate loop to keep this
+ * one tight.
+ *
+ * Symbol stringifying is a TypeError, so into the slow path
+ * with those as well.
+ */
+ break;
+ } else if (elem.isBigInt()) {
+ // ToString(bigint) doesn't access bigint.toString or
+ // anything like that, so it can't mutate the array we're
+ // walking through, so it *could* be handled here. We don't
+ // do so yet for reasons of initial-implementation economy.
+ break;
+ } else {
+ MOZ_ASSERT(elem.isMagic(JS_ELEMENTS_HOLE) || elem.isNullOrUndefined());
+ }
+
+ // Steps 7.a, 7.e.
+ if (++(*numProcessed) != length && !sepOp(cx, sb)) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+template <typename SeparatorOp>
+static bool ArrayJoinKernel(JSContext* cx, SeparatorOp sepOp, HandleObject obj,
+ uint64_t length, StringBuffer& sb) {
+ // Step 6.
+ uint32_t numProcessed = 0;
+
+ if (IsPackedArrayOrNoExtraIndexedProperties(obj, length)) {
+ if (!ArrayJoinDenseKernel<SeparatorOp>(cx, sepOp, obj.as<NativeObject>(),
+ length, sb, &numProcessed)) {
+ return false;
+ }
+ }
+
+ // Step 7.
+ if (numProcessed != length) {
+ RootedValue v(cx);
+ for (uint64_t i = numProcessed; i < length;) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ // Step 7.b.
+ if (!GetArrayElement(cx, obj, i, &v)) {
+ return false;
+ }
+
+ // Steps 7.c-d.
+ if (!v.isNullOrUndefined()) {
+ if (!ValueToStringBuffer(cx, v, sb)) {
+ return false;
+ }
+ }
+
+ // Steps 7.a, 7.e.
+ if (++i != length && !sepOp(cx, sb)) {
+ return false;
+ }
+ }
+ }
+
+ return true;
+}
+
+// ES2017 draft rev 1b0184bc17fc09a8ddcf4aeec9b6d9fcac4eafce
+// 22.1.3.13 Array.prototype.join ( separator )
+bool js::array_join(JSContext* cx, unsigned argc, Value* vp) {
+ if (!CheckRecursionLimit(cx)) {
+ return false;
+ }
+
+ AutoGeckoProfilerEntry pseudoFrame(
+ cx, "Array.prototype.join", JS::ProfilingCategoryPair::JS,
+ uint32_t(ProfilingStackFrame::Flags::RELEVANT_FOR_JS));
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ // Step 1.
+ RootedObject obj(cx, ToObject(cx, args.thisv()));
+ if (!obj) {
+ return false;
+ }
+
+ AutoCycleDetector detector(cx, obj);
+ if (!detector.init()) {
+ return false;
+ }
+
+ if (detector.foundCycle()) {
+ args.rval().setString(cx->names().empty);
+ return true;
+ }
+
+ // Step 2.
+ uint64_t length;
+ if (!GetLengthProperty(cx, obj, &length)) {
+ return false;
+ }
+
+ // Steps 3-4.
+ RootedLinearString sepstr(cx);
+ if (args.hasDefined(0)) {
+ JSString* s = ToString<CanGC>(cx, args[0]);
+ if (!s) {
+ return false;
+ }
+ sepstr = s->ensureLinear(cx);
+ if (!sepstr) {
+ return false;
+ }
+ } else {
+ sepstr = cx->names().comma;
+ }
+
+ // Steps 5-8 (When the length is zero, directly return the empty string).
+ if (length == 0) {
+ args.rval().setString(cx->emptyString());
+ return true;
+ }
+
+ // An optimized version of a special case of steps 5-8: when length==1 and
+ // the 0th element is a string, ToString() of that element is a no-op and
+ // so it can be immediately returned as the result.
+ if (length == 1 && obj->isNative()) {
+ NativeObject* nobj = &obj->as<NativeObject>();
+ if (nobj->getDenseInitializedLength() == 1) {
+ Value elem0 = nobj->getDenseElement(0);
+ if (elem0.isString()) {
+ args.rval().set(elem0);
+ return true;
+ }
+ }
+ }
+
+ // Step 5.
+ JSStringBuilder sb(cx);
+ if (sepstr->hasTwoByteChars() && !sb.ensureTwoByteChars()) {
+ return false;
+ }
+
+ // The separator will be added |length - 1| times, reserve space for that
+ // so that we don't have to unnecessarily grow the buffer.
+ size_t seplen = sepstr->length();
+ if (seplen > 0) {
+ if (length > UINT32_MAX) {
+ ReportAllocationOverflow(cx);
+ return false;
+ }
+ CheckedInt<uint32_t> res =
+ CheckedInt<uint32_t>(seplen) * (uint32_t(length) - 1);
+ if (!res.isValid()) {
+ ReportAllocationOverflow(cx);
+ return false;
+ }
+
+ if (!sb.reserve(res.value())) {
+ return false;
+ }
+ }
+
+ // Various optimized versions of steps 6-7.
+ if (seplen == 0) {
+ EmptySeparatorOp op;
+ if (!ArrayJoinKernel(cx, op, obj, length, sb)) {
+ return false;
+ }
+ } else if (seplen == 1) {
+ char16_t c = sepstr->latin1OrTwoByteChar(0);
+ if (c <= JSString::MAX_LATIN1_CHAR) {
+ CharSeparatorOp<Latin1Char> op(c);
+ if (!ArrayJoinKernel(cx, op, obj, length, sb)) {
+ return false;
+ }
+ } else {
+ CharSeparatorOp<char16_t> op(c);
+ if (!ArrayJoinKernel(cx, op, obj, length, sb)) {
+ return false;
+ }
+ }
+ } else {
+ StringSeparatorOp op(sepstr);
+ if (!ArrayJoinKernel(cx, op, obj, length, sb)) {
+ return false;
+ }
+ }
+
+ // Step 8.
+ JSString* str = sb.finishString();
+ if (!str) {
+ return false;
+ }
+
+ args.rval().setString(str);
+ return true;
+}
+
+// ES2017 draft rev f8a9be8ea4bd97237d176907a1e3080dce20c68f
+// 22.1.3.27 Array.prototype.toLocaleString ([ reserved1 [ , reserved2 ] ])
+// ES2017 Intl draft rev 78bbe7d1095f5ff3760ac4017ed366026e4cb276
+// 13.4.1 Array.prototype.toLocaleString ([ locales [ , options ]])
+static bool array_toLocaleString(JSContext* cx, unsigned argc, Value* vp) {
+ if (!CheckRecursionLimit(cx)) {
+ return false;
+ }
+
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ // Step 1
+ RootedObject obj(cx, ToObject(cx, args.thisv()));
+ if (!obj) {
+ return false;
+ }
+
+ // Avoid calling into self-hosted code if the array is empty.
+ if (obj->is<ArrayObject>() && obj->as<ArrayObject>().length() == 0) {
+ args.rval().setString(cx->names().empty);
+ return true;
+ }
+
+ AutoCycleDetector detector(cx, obj);
+ if (!detector.init()) {
+ return false;
+ }
+
+ if (detector.foundCycle()) {
+ args.rval().setString(cx->names().empty);
+ return true;
+ }
+
+ FixedInvokeArgs<2> args2(cx);
+
+ args2[0].set(args.get(0));
+ args2[1].set(args.get(1));
+
+ // Steps 2-10.
+ RootedValue thisv(cx, ObjectValue(*obj));
+ return CallSelfHostedFunction(cx, cx->names().ArrayToLocaleString, thisv,
+ args2, args.rval());
+}
+
+/* vector must point to rooted memory. */
+static bool SetArrayElements(JSContext* cx, HandleObject obj, uint64_t start,
+ uint32_t count, const Value* vector) {
+ MOZ_ASSERT(count <= MAX_ARRAY_INDEX);
+ MOZ_ASSERT(start + count < uint64_t(DOUBLE_INTEGRAL_PRECISION_LIMIT));
+
+ if (count == 0) {
+ return true;
+ }
+
+ if (!ObjectMayHaveExtraIndexedProperties(obj) && start <= UINT32_MAX) {
+ NativeObject* nobj = &obj->as<NativeObject>();
+ DenseElementResult result =
+ nobj->setOrExtendDenseElements(cx, uint32_t(start), vector, count);
+ if (result != DenseElementResult::Incomplete) {
+ return result == DenseElementResult::Success;
+ }
+ }
+
+ RootedId id(cx);
+ const Value* end = vector + count;
+ while (vector < end) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ if (!ToId(cx, start++, &id)) {
+ return false;
+ }
+
+ if (!SetProperty(cx, obj, id, HandleValue::fromMarkedLocation(vector++))) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static DenseElementResult ArrayReverseDenseKernel(JSContext* cx,
+ HandleNativeObject obj,
+ uint32_t length) {
+ MOZ_ASSERT(length > 1);
+
+ // If there are no elements, we're done.
+ if (obj->getDenseInitializedLength() == 0) {
+ return DenseElementResult::Success;
+ }
+
+ if (!obj->isExtensible()) {
+ return DenseElementResult::Incomplete;
+ }
+
+ if (!IsPackedArray(obj)) {
+ /*
+ * It's actually surprisingly complicated to reverse an array due
+ * to the orthogonality of array length and array capacity while
+ * handling leading and trailing holes correctly. Reversing seems
+ * less likely to be a common operation than other array
+ * mass-mutation methods, so for now just take a probably-small
+ * memory hit (in the absence of too many holes in the array at
+ * its start) and ensure that the capacity is sufficient to hold
+ * all the elements in the array if it were full.
+ */
+ DenseElementResult result = obj->ensureDenseElements(cx, length, 0);
+ if (result != DenseElementResult::Success) {
+ return result;
+ }
+
+ /* Fill out the array's initialized length to its proper length. */
+ obj->ensureDenseInitializedLength(length, 0);
+ }
+
+ if (!obj->denseElementsMaybeInIteration() &&
+ !cx->zone()->needsIncrementalBarrier()) {
+ obj->reverseDenseElementsNoPreBarrier(length);
+ return DenseElementResult::Success;
+ }
+
+ auto setElementMaybeHole = [](JSContext* cx, HandleNativeObject obj,
+ uint32_t index, const Value& val) {
+ if (MOZ_LIKELY(!val.isMagic(JS_ELEMENTS_HOLE))) {
+ obj->setDenseElement(index, val);
+ return true;
+ }
+
+ obj->setDenseElementHole(index);
+ return SuppressDeletedProperty(cx, obj, INT_TO_JSID(index));
+ };
+
+ RootedValue origlo(cx), orighi(cx);
+
+ uint32_t lo = 0, hi = length - 1;
+ for (; lo < hi; lo++, hi--) {
+ origlo = obj->getDenseElement(lo);
+ orighi = obj->getDenseElement(hi);
+ if (!setElementMaybeHole(cx, obj, lo, orighi)) {
+ return DenseElementResult::Failure;
+ }
+ if (!setElementMaybeHole(cx, obj, hi, origlo)) {
+ return DenseElementResult::Failure;
+ }
+ }
+
+ return DenseElementResult::Success;
+}
+
+// ES2017 draft rev 1b0184bc17fc09a8ddcf4aeec9b6d9fcac4eafce
+// 22.1.3.21 Array.prototype.reverse ( )
+static bool array_reverse(JSContext* cx, unsigned argc, Value* vp) {
+ AutoGeckoProfilerEntry pseudoFrame(
+ cx, "Array.prototype.reverse", JS::ProfilingCategoryPair::JS,
+ uint32_t(ProfilingStackFrame::Flags::RELEVANT_FOR_JS));
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ // Step 1.
+ RootedObject obj(cx, ToObject(cx, args.thisv()));
+ if (!obj) {
+ return false;
+ }
+
+ // Step 2.
+ uint64_t len;
+ if (!GetLengthProperty(cx, obj, &len)) {
+ return false;
+ }
+
+ // An empty array or an array with length 1 is already reversed.
+ if (len <= 1) {
+ args.rval().setObject(*obj);
+ return true;
+ }
+
+ if (IsPackedArrayOrNoExtraIndexedProperties(obj, len) && len <= UINT32_MAX) {
+ DenseElementResult result =
+ ArrayReverseDenseKernel(cx, obj.as<NativeObject>(), uint32_t(len));
+ if (result != DenseElementResult::Incomplete) {
+ /*
+ * Per ECMA-262, don't update the length of the array, even if the new
+ * array has trailing holes (and thus the original array began with
+ * holes).
+ */
+ args.rval().setObject(*obj);
+ return result == DenseElementResult::Success;
+ }
+ }
+
+ // Steps 3-5.
+ RootedValue lowval(cx), hival(cx);
+ for (uint64_t i = 0, half = len / 2; i < half; i++) {
+ bool hole, hole2;
+ if (!CheckForInterrupt(cx) ||
+ !HasAndGetElement(cx, obj, i, &hole, &lowval) ||
+ !HasAndGetElement(cx, obj, len - i - 1, &hole2, &hival)) {
+ return false;
+ }
+
+ if (!hole && !hole2) {
+ if (!SetArrayElement(cx, obj, i, hival)) {
+ return false;
+ }
+ if (!SetArrayElement(cx, obj, len - i - 1, lowval)) {
+ return false;
+ }
+ } else if (hole && !hole2) {
+ if (!SetArrayElement(cx, obj, i, hival)) {
+ return false;
+ }
+ if (!DeletePropertyOrThrow(cx, obj, len - i - 1)) {
+ return false;
+ }
+ } else if (!hole && hole2) {
+ if (!DeletePropertyOrThrow(cx, obj, i)) {
+ return false;
+ }
+ if (!SetArrayElement(cx, obj, len - i - 1, lowval)) {
+ return false;
+ }
+ } else {
+ // No action required.
+ }
+ }
+
+ // Step 6.
+ args.rval().setObject(*obj);
+ return true;
+}
+
+static inline bool CompareStringValues(JSContext* cx, const Value& a,
+ const Value& b, bool* lessOrEqualp) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ JSString* astr = a.toString();
+ JSString* bstr = b.toString();
+ int32_t result;
+ if (!CompareStrings(cx, astr, bstr, &result)) {
+ return false;
+ }
+
+ *lessOrEqualp = (result <= 0);
+ return true;
+}
+
+static const uint64_t powersOf10[] = {
+ 1, 10, 100, 1000, 10000, 100000,
+ 1000000, 10000000, 100000000, 1000000000, 1000000000000ULL};
+
+static inline unsigned NumDigitsBase10(uint32_t n) {
+ /*
+ * This is just floor_log10(n) + 1
+ * Algorithm taken from
+ * http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10
+ */
+ uint32_t log2 = CeilingLog2(n);
+ uint32_t t = log2 * 1233 >> 12;
+ return t - (n < powersOf10[t]) + 1;
+}
+
+static inline bool CompareLexicographicInt32(const Value& a, const Value& b,
+ bool* lessOrEqualp) {
+ int32_t aint = a.toInt32();
+ int32_t bint = b.toInt32();
+
+ /*
+ * If both numbers are equal ... trivial
+ * If only one of both is negative --> arithmetic comparison as char code
+ * of '-' is always less than any other digit
+ * If both numbers are negative convert them to positive and continue
+ * handling ...
+ */
+ if (aint == bint) {
+ *lessOrEqualp = true;
+ } else if ((aint < 0) && (bint >= 0)) {
+ *lessOrEqualp = true;
+ } else if ((aint >= 0) && (bint < 0)) {
+ *lessOrEqualp = false;
+ } else {
+ uint32_t auint = Abs(aint);
+ uint32_t buint = Abs(bint);
+
+ /*
+ * ... get number of digits of both integers.
+ * If they have the same number of digits --> arithmetic comparison.
+ * If digits_a > digits_b: a < b*10e(digits_a - digits_b).
+ * If digits_b > digits_a: a*10e(digits_b - digits_a) <= b.
+ */
+ unsigned digitsa = NumDigitsBase10(auint);
+ unsigned digitsb = NumDigitsBase10(buint);
+ if (digitsa == digitsb) {
+ *lessOrEqualp = (auint <= buint);
+ } else if (digitsa > digitsb) {
+ MOZ_ASSERT((digitsa - digitsb) < std::size(powersOf10));
+ *lessOrEqualp =
+ (uint64_t(auint) < uint64_t(buint) * powersOf10[digitsa - digitsb]);
+ } else { /* if (digitsb > digitsa) */
+ MOZ_ASSERT((digitsb - digitsa) < std::size(powersOf10));
+ *lessOrEqualp =
+ (uint64_t(auint) * powersOf10[digitsb - digitsa] <= uint64_t(buint));
+ }
+ }
+
+ return true;
+}
+
+template <typename Char1, typename Char2>
+static inline bool CompareSubStringValues(JSContext* cx, const Char1* s1,
+ size_t len1, const Char2* s2,
+ size_t len2, bool* lessOrEqualp) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ if (!s1 || !s2) {
+ return false;
+ }
+
+ int32_t result = CompareChars(s1, len1, s2, len2);
+ *lessOrEqualp = (result <= 0);
+ return true;
+}
+
+namespace {
+
+struct SortComparatorStrings {
+ JSContext* const cx;
+
+ explicit SortComparatorStrings(JSContext* cx) : cx(cx) {}
+
+ bool operator()(const Value& a, const Value& b, bool* lessOrEqualp) {
+ return CompareStringValues(cx, a, b, lessOrEqualp);
+ }
+};
+
+struct SortComparatorLexicographicInt32 {
+ bool operator()(const Value& a, const Value& b, bool* lessOrEqualp) {
+ return CompareLexicographicInt32(a, b, lessOrEqualp);
+ }
+};
+
+struct StringifiedElement {
+ size_t charsBegin;
+ size_t charsEnd;
+ size_t elementIndex;
+};
+
+struct SortComparatorStringifiedElements {
+ JSContext* const cx;
+ const StringBuffer& sb;
+
+ SortComparatorStringifiedElements(JSContext* cx, const StringBuffer& sb)
+ : cx(cx), sb(sb) {}
+
+ bool operator()(const StringifiedElement& a, const StringifiedElement& b,
+ bool* lessOrEqualp) {
+ size_t lenA = a.charsEnd - a.charsBegin;
+ size_t lenB = b.charsEnd - b.charsBegin;
+
+ if (sb.isUnderlyingBufferLatin1()) {
+ return CompareSubStringValues(cx, sb.rawLatin1Begin() + a.charsBegin,
+ lenA, sb.rawLatin1Begin() + b.charsBegin,
+ lenB, lessOrEqualp);
+ }
+
+ return CompareSubStringValues(cx, sb.rawTwoByteBegin() + a.charsBegin, lenA,
+ sb.rawTwoByteBegin() + b.charsBegin, lenB,
+ lessOrEqualp);
+ }
+};
+
+struct NumericElement {
+ double dv;
+ size_t elementIndex;
+};
+
+static bool ComparatorNumericLeftMinusRight(const NumericElement& a,
+ const NumericElement& b,
+ bool* lessOrEqualp) {
+ *lessOrEqualp = (a.dv <= b.dv);
+ return true;
+}
+
+static bool ComparatorNumericRightMinusLeft(const NumericElement& a,
+ const NumericElement& b,
+ bool* lessOrEqualp) {
+ *lessOrEqualp = (b.dv <= a.dv);
+ return true;
+}
+
+using ComparatorNumeric = bool (*)(const NumericElement&, const NumericElement&,
+ bool*);
+
+static const ComparatorNumeric SortComparatorNumerics[] = {
+ nullptr, nullptr, ComparatorNumericLeftMinusRight,
+ ComparatorNumericRightMinusLeft};
+
+static bool ComparatorInt32LeftMinusRight(const Value& a, const Value& b,
+ bool* lessOrEqualp) {
+ *lessOrEqualp = (a.toInt32() <= b.toInt32());
+ return true;
+}
+
+static bool ComparatorInt32RightMinusLeft(const Value& a, const Value& b,
+ bool* lessOrEqualp) {
+ *lessOrEqualp = (b.toInt32() <= a.toInt32());
+ return true;
+}
+
+using ComparatorInt32 = bool (*)(const Value&, const Value&, bool*);
+
+static const ComparatorInt32 SortComparatorInt32s[] = {
+ nullptr, nullptr, ComparatorInt32LeftMinusRight,
+ ComparatorInt32RightMinusLeft};
+
+// Note: Values for this enum must match up with SortComparatorNumerics
+// and SortComparatorInt32s.
+enum ComparatorMatchResult {
+ Match_Failure = 0,
+ Match_None,
+ Match_LeftMinusRight,
+ Match_RightMinusLeft
+};
+
+} // namespace
+
+/*
+ * Specialize behavior for comparator functions with particular common bytecode
+ * patterns: namely, |return x - y| and |return y - x|.
+ */
+static ComparatorMatchResult MatchNumericComparator(JSContext* cx,
+ JSObject* obj) {
+ if (!obj->is<JSFunction>()) {
+ return Match_None;
+ }
+
+ RootedFunction fun(cx, &obj->as<JSFunction>());
+ if (!fun->isInterpreted() || fun->isClassConstructor()) {
+ return Match_None;
+ }
+
+ JSScript* script = JSFunction::getOrCreateScript(cx, fun);
+ if (!script) {
+ return Match_Failure;
+ }
+
+ jsbytecode* pc = script->code();
+
+ uint16_t arg0, arg1;
+ if (JSOp(*pc) != JSOp::GetArg) {
+ return Match_None;
+ }
+ arg0 = GET_ARGNO(pc);
+ pc += JSOpLength_GetArg;
+
+ if (JSOp(*pc) != JSOp::GetArg) {
+ return Match_None;
+ }
+ arg1 = GET_ARGNO(pc);
+ pc += JSOpLength_GetArg;
+
+ if (JSOp(*pc) != JSOp::Sub) {
+ return Match_None;
+ }
+ pc += JSOpLength_Sub;
+
+ if (JSOp(*pc) != JSOp::Return) {
+ return Match_None;
+ }
+
+ if (arg0 == 0 && arg1 == 1) {
+ return Match_LeftMinusRight;
+ }
+
+ if (arg0 == 1 && arg1 == 0) {
+ return Match_RightMinusLeft;
+ }
+
+ return Match_None;
+}
+
+template <typename K, typename C>
+static inline bool MergeSortByKey(K keys, size_t len, K scratch, C comparator,
+ MutableHandle<GCVector<Value>> vec) {
+ MOZ_ASSERT(vec.length() >= len);
+
+ /* Sort keys. */
+ if (!MergeSort(keys, len, scratch, comparator)) {
+ return false;
+ }
+
+ /*
+ * Reorder vec by keys in-place, going element by element. When an out-of-
+ * place element is encountered, move that element to its proper position,
+ * displacing whatever element was at *that* point to its proper position,
+ * and so on until an element must be moved to the current position.
+ *
+ * At each outer iteration all elements up to |i| are sorted. If
+ * necessary each inner iteration moves some number of unsorted elements
+ * (including |i|) directly to sorted position. Thus on completion |*vec|
+ * is sorted, and out-of-position elements have moved once. Complexity is
+ * Θ(len) + O(len) == O(2*len), with each element visited at most twice.
+ */
+ for (size_t i = 0; i < len; i++) {
+ size_t j = keys[i].elementIndex;
+ if (i == j) {
+ continue; // fixed point
+ }
+
+ MOZ_ASSERT(j > i, "Everything less than |i| should be in the right place!");
+ Value tv = vec[j];
+ do {
+ size_t k = keys[j].elementIndex;
+ keys[j].elementIndex = j;
+ vec[j].set(vec[k]);
+ j = k;
+ } while (j != i);
+
+ // We could assert the loop invariant that |i == keys[i].elementIndex|
+ // here if we synced |keys[i].elementIndex|. But doing so would render
+ // the assertion vacuous, so don't bother, even in debug builds.
+ vec[i].set(tv);
+ }
+
+ return true;
+}
+
+/*
+ * Sort Values as strings.
+ *
+ * To minimize #conversions, SortLexicographically() first converts all Values
+ * to strings at once, then sorts the elements by these cached strings.
+ */
+static bool SortLexicographically(JSContext* cx,
+ MutableHandle<GCVector<Value>> vec,
+ size_t len) {
+ MOZ_ASSERT(vec.length() >= len);
+
+ StringBuffer sb(cx);
+ Vector<StringifiedElement, 0, TempAllocPolicy> strElements(cx);
+
+ /* MergeSort uses the upper half as scratch space. */
+ if (!strElements.resize(2 * len)) {
+ return false;
+ }
+
+ /* Convert Values to strings. */
+ size_t cursor = 0;
+ for (size_t i = 0; i < len; i++) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ if (!ValueToStringBuffer(cx, vec[i], sb)) {
+ return false;
+ }
+
+ strElements[i] = {cursor, sb.length(), i};
+ cursor = sb.length();
+ }
+
+ /* Sort Values in vec alphabetically. */
+ return MergeSortByKey(strElements.begin(), len, strElements.begin() + len,
+ SortComparatorStringifiedElements(cx, sb), vec);
+}
+
+/*
+ * Sort Values as numbers.
+ *
+ * To minimize #conversions, SortNumerically first converts all Values to
+ * numerics at once, then sorts the elements by these cached numerics.
+ */
+static bool SortNumerically(JSContext* cx, MutableHandle<GCVector<Value>> vec,
+ size_t len, ComparatorMatchResult comp) {
+ MOZ_ASSERT(vec.length() >= len);
+
+ Vector<NumericElement, 0, TempAllocPolicy> numElements(cx);
+
+ /* MergeSort uses the upper half as scratch space. */
+ if (!numElements.resize(2 * len)) {
+ return false;
+ }
+
+ /* Convert Values to numerics. */
+ for (size_t i = 0; i < len; i++) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ double dv;
+ if (!ToNumber(cx, vec[i], &dv)) {
+ return false;
+ }
+
+ numElements[i] = {dv, i};
+ }
+
+ /* Sort Values in vec numerically. */
+ return MergeSortByKey(numElements.begin(), len, numElements.begin() + len,
+ SortComparatorNumerics[comp], vec);
+}
+
+static bool FillWithUndefined(JSContext* cx, HandleObject obj, uint32_t start,
+ uint32_t count) {
+ MOZ_ASSERT(start < start + count,
+ "count > 0 and start + count doesn't overflow");
+
+ do {
+ if (ObjectMayHaveExtraIndexedProperties(obj)) {
+ break;
+ }
+
+ NativeObject* nobj = &obj->as<NativeObject>();
+ if (!nobj->isExtensible()) {
+ break;
+ }
+
+ if (obj->is<ArrayObject>() && !obj->as<ArrayObject>().lengthIsWritable() &&
+ start + count >= obj->as<ArrayObject>().length()) {
+ break;
+ }
+
+ DenseElementResult result = nobj->ensureDenseElements(cx, start, count);
+ if (result != DenseElementResult::Success) {
+ if (result == DenseElementResult::Failure) {
+ return false;
+ }
+ MOZ_ASSERT(result == DenseElementResult::Incomplete);
+ break;
+ }
+
+ if (obj->is<ArrayObject>() &&
+ start + count >= obj->as<ArrayObject>().length()) {
+ obj->as<ArrayObject>().setLength(start + count);
+ }
+
+ for (uint32_t i = 0; i < count; i++) {
+ nobj->setDenseElement(start + i, UndefinedHandleValue);
+ }
+
+ return true;
+ } while (false);
+
+ for (uint32_t i = 0; i < count; i++) {
+ if (!CheckForInterrupt(cx) ||
+ !SetArrayElement(cx, obj, start + i, UndefinedHandleValue)) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+bool js::intrinsic_ArrayNativeSort(JSContext* cx, unsigned argc, Value* vp) {
+ // This function is called from the self-hosted Array.prototype.sort
+ // implementation. It returns |true| if the array was sorted, otherwise it
+ // returns |false| to notify the self-hosted code to perform the sorting.
+ CallArgs args = CallArgsFromVp(argc, vp);
+ MOZ_ASSERT(args.length() == 1);
+
+ HandleValue fval = args[0];
+ MOZ_ASSERT(fval.isUndefined() || IsCallable(fval));
+
+ ComparatorMatchResult comp;
+ if (fval.isObject()) {
+ comp = MatchNumericComparator(cx, &fval.toObject());
+ if (comp == Match_Failure) {
+ return false;
+ }
+
+ if (comp == Match_None) {
+ // Non-optimized user supplied comparators perform much better when
+ // called from within a self-hosted sorting function.
+ args.rval().setBoolean(false);
+ return true;
+ }
+ } else {
+ comp = Match_None;
+ }
+
+ RootedObject obj(cx, &args.thisv().toObject());
+
+ uint64_t length;
+ if (!GetLengthProperty(cx, obj, &length)) {
+ return false;
+ }
+ if (length < 2) {
+ /* [] and [a] remain unchanged when sorted. */
+ args.rval().setBoolean(true);
+ return true;
+ }
+
+ if (length > UINT32_MAX) {
+ ReportAllocationOverflow(cx);
+ return false;
+ }
+ uint32_t len = uint32_t(length);
+
+ /*
+ * We need a temporary array of 2 * len Value to hold the array elements
+ * and the scratch space for merge sort. Check that its size does not
+ * overflow size_t, which would allow for indexing beyond the end of the
+ * malloc'd vector.
+ */
+#if JS_BITS_PER_WORD == 32
+ if (size_t(len) > size_t(-1) / (2 * sizeof(Value))) {
+ ReportAllocationOverflow(cx);
+ return false;
+ }
+#endif
+
+ size_t n, undefs;
+ {
+ Rooted<GCVector<Value>> vec(cx, GCVector<Value>(cx));
+ if (!vec.reserve(2 * size_t(len))) {
+ return false;
+ }
+
+ /*
+ * By ECMA 262, 15.4.4.11, a property that does not exist (which we
+ * call a "hole") is always greater than an existing property with
+ * value undefined and that is always greater than any other property.
+ * Thus to sort holes and undefs we simply count them, sort the rest
+ * of elements, append undefs after them and then make holes after
+ * undefs.
+ */
+ undefs = 0;
+ bool allStrings = true;
+ bool allInts = true;
+ RootedValue v(cx);
+ if (IsPackedArray(obj)) {
+ HandleArrayObject array = obj.as<ArrayObject>();
+
+ for (uint32_t i = 0; i < len; i++) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ v.set(array->getDenseElement(i));
+ MOZ_ASSERT(!v.isMagic(JS_ELEMENTS_HOLE));
+ if (v.isUndefined()) {
+ ++undefs;
+ continue;
+ }
+ vec.infallibleAppend(v);
+ allStrings = allStrings && v.isString();
+ allInts = allInts && v.isInt32();
+ }
+ } else {
+ for (uint32_t i = 0; i < len; i++) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ bool hole;
+ if (!HasAndGetElement(cx, obj, i, &hole, &v)) {
+ return false;
+ }
+ if (hole) {
+ continue;
+ }
+ if (v.isUndefined()) {
+ ++undefs;
+ continue;
+ }
+ vec.infallibleAppend(v);
+ allStrings = allStrings && v.isString();
+ allInts = allInts && v.isInt32();
+ }
+ }
+
+ /*
+ * If the array only contains holes, we're done. But if it contains
+ * undefs, those must be sorted to the front of the array.
+ */
+ n = vec.length();
+ if (n == 0 && undefs == 0) {
+ args.rval().setBoolean(true);
+ return true;
+ }
+
+ /* Here len == n + undefs + number_of_holes. */
+ if (comp == Match_None) {
+ /*
+ * Sort using the default comparator converting all elements to
+ * strings.
+ */
+ if (allStrings) {
+ MOZ_ALWAYS_TRUE(vec.resize(n * 2));
+ if (!MergeSort(vec.begin(), n, vec.begin() + n,
+ SortComparatorStrings(cx))) {
+ return false;
+ }
+ } else if (allInts) {
+ MOZ_ALWAYS_TRUE(vec.resize(n * 2));
+ if (!MergeSort(vec.begin(), n, vec.begin() + n,
+ SortComparatorLexicographicInt32())) {
+ return false;
+ }
+ } else {
+ if (!SortLexicographically(cx, &vec, n)) {
+ return false;
+ }
+ }
+ } else {
+ if (allInts) {
+ MOZ_ALWAYS_TRUE(vec.resize(n * 2));
+ if (!MergeSort(vec.begin(), n, vec.begin() + n,
+ SortComparatorInt32s[comp])) {
+ return false;
+ }
+ } else {
+ if (!SortNumerically(cx, &vec, n, comp)) {
+ return false;
+ }
+ }
+ }
+
+ if (!SetArrayElements(cx, obj, 0, uint32_t(n), vec.begin())) {
+ return false;
+ }
+ }
+
+ /* Set undefs that sorted after the rest of elements. */
+ if (undefs > 0) {
+ if (!FillWithUndefined(cx, obj, n, undefs)) {
+ return false;
+ }
+ n += undefs;
+ }
+
+ /* Re-create any holes that sorted to the end of the array. */
+ for (uint32_t i = n; i < len; i++) {
+ if (!CheckForInterrupt(cx) || !DeletePropertyOrThrow(cx, obj, i)) {
+ return false;
+ }
+ }
+ args.rval().setBoolean(true);
+ return true;
+}
+
+bool js::NewbornArrayPush(JSContext* cx, HandleObject obj, const Value& v) {
+ HandleArrayObject arr = obj.as<ArrayObject>();
+
+ MOZ_ASSERT(!v.isMagic());
+ MOZ_ASSERT(arr->lengthIsWritable());
+
+ uint32_t length = arr->length();
+ MOZ_ASSERT(length <= arr->getDenseCapacity());
+
+ if (!arr->ensureElements(cx, length + 1)) {
+ return false;
+ }
+
+ arr->setDenseInitializedLength(length + 1);
+ arr->setLength(length + 1);
+ arr->initDenseElement(length, v);
+ return true;
+}
+
+// ES2017 draft rev 1b0184bc17fc09a8ddcf4aeec9b6d9fcac4eafce
+// 22.1.3.18 Array.prototype.push ( ...items )
+bool js::array_push(JSContext* cx, unsigned argc, Value* vp) {
+ AutoGeckoProfilerEntry pseudoFrame(
+ cx, "Array.prototype.push", JS::ProfilingCategoryPair::JS,
+ uint32_t(ProfilingStackFrame::Flags::RELEVANT_FOR_JS));
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ // Step 1.
+ RootedObject obj(cx, ToObject(cx, args.thisv()));
+ if (!obj) {
+ return false;
+ }
+
+ // Step 2.
+ uint64_t length;
+ if (!GetLengthProperty(cx, obj, &length)) {
+ return false;
+ }
+
+ if (!ObjectMayHaveExtraIndexedProperties(obj) && length <= UINT32_MAX) {
+ DenseElementResult result =
+ obj->as<NativeObject>().setOrExtendDenseElements(
+ cx, uint32_t(length), args.array(), args.length());
+ if (result != DenseElementResult::Incomplete) {
+ if (result == DenseElementResult::Failure) {
+ return false;
+ }
+
+ uint32_t newlength = uint32_t(length) + args.length();
+ args.rval().setNumber(newlength);
+
+ // setOrExtendDenseElements takes care of updating the length for
+ // arrays. Handle updates to the length of non-arrays here.
+ if (!obj->is<ArrayObject>()) {
+ MOZ_ASSERT(obj->is<NativeObject>());
+ return SetLengthProperty(cx, obj, newlength);
+ }
+
+ return true;
+ }
+ }
+
+ // Step 5.
+ uint64_t newlength = length + args.length();
+ if (newlength >= uint64_t(DOUBLE_INTEGRAL_PRECISION_LIMIT)) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_TOO_LONG_ARRAY);
+ return false;
+ }
+
+ // Steps 3-6.
+ if (!SetArrayElements(cx, obj, length, args.length(), args.array())) {
+ return false;
+ }
+
+ // Steps 7-8.
+ args.rval().setNumber(double(newlength));
+ return SetLengthProperty(cx, obj, newlength);
+}
+
+// ES2017 draft rev 1b0184bc17fc09a8ddcf4aeec9b6d9fcac4eafce
+// 22.1.3.17 Array.prototype.pop ( )
+bool js::array_pop(JSContext* cx, unsigned argc, Value* vp) {
+ AutoGeckoProfilerEntry pseudoFrame(
+ cx, "Array.prototype.pop", JS::ProfilingCategoryPair::JS,
+ uint32_t(ProfilingStackFrame::Flags::RELEVANT_FOR_JS));
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ // Step 1.
+ RootedObject obj(cx, ToObject(cx, args.thisv()));
+ if (!obj) {
+ return false;
+ }
+
+ // Step 2.
+ uint64_t index;
+ if (!GetLengthProperty(cx, obj, &index)) {
+ return false;
+ }
+
+ // Steps 3-4.
+ if (index == 0) {
+ // Step 3.b.
+ args.rval().setUndefined();
+ } else {
+ // Steps 4.a-b.
+ index--;
+
+ // Steps 4.c, 4.f.
+ if (!GetArrayElement(cx, obj, index, args.rval())) {
+ return false;
+ }
+
+ // Steps 4.d.
+ if (!DeletePropertyOrThrow(cx, obj, index)) {
+ return false;
+ }
+ }
+
+ // Steps 3.a, 4.e.
+ return SetLengthProperty(cx, obj, index);
+}
+
+void js::ArrayShiftMoveElements(ArrayObject* arr) {
+ AutoUnsafeCallWithABI unsafe;
+ MOZ_ASSERT(arr->isExtensible());
+ MOZ_ASSERT(arr->lengthIsWritable());
+ MOZ_ASSERT(IsPackedArray(arr));
+ MOZ_ASSERT(!arr->denseElementsHaveMaybeInIterationFlag());
+
+ size_t initlen = arr->getDenseInitializedLength();
+ MOZ_ASSERT(initlen > 0);
+
+ if (!arr->tryShiftDenseElements(1)) {
+ arr->moveDenseElements(0, 1, initlen - 1);
+ }
+}
+
+static inline void SetInitializedLength(JSContext* cx, NativeObject* obj,
+ size_t initlen) {
+ MOZ_ASSERT(obj->isExtensible());
+
+ size_t oldInitlen = obj->getDenseInitializedLength();
+ obj->setDenseInitializedLength(initlen);
+ if (initlen < oldInitlen) {
+ obj->shrinkElements(cx, initlen);
+ }
+}
+
+static DenseElementResult ArrayShiftDenseKernel(JSContext* cx, HandleObject obj,
+ MutableHandleValue rval) {
+ if (!IsPackedArray(obj) && ObjectMayHaveExtraIndexedProperties(obj)) {
+ return DenseElementResult::Incomplete;
+ }
+
+ HandleNativeObject nobj = obj.as<NativeObject>();
+ if (nobj->denseElementsMaybeInIteration()) {
+ return DenseElementResult::Incomplete;
+ }
+
+ if (!nobj->isExtensible()) {
+ return DenseElementResult::Incomplete;
+ }
+
+ size_t initlen = nobj->getDenseInitializedLength();
+ if (initlen == 0) {
+ return DenseElementResult::Incomplete;
+ }
+
+ rval.set(nobj->getDenseElement(0));
+ if (rval.isMagic(JS_ELEMENTS_HOLE)) {
+ rval.setUndefined();
+ }
+
+ if (nobj->tryShiftDenseElements(1)) {
+ return DenseElementResult::Success;
+ }
+
+ nobj->moveDenseElements(0, 1, initlen - 1);
+
+ SetInitializedLength(cx, nobj, initlen - 1);
+ return DenseElementResult::Success;
+}
+
+// ES2017 draft rev 1b0184bc17fc09a8ddcf4aeec9b6d9fcac4eafce
+// 22.1.3.22 Array.prototype.shift ( )
+bool js::array_shift(JSContext* cx, unsigned argc, Value* vp) {
+ AutoGeckoProfilerEntry pseudoFrame(
+ cx, "Array.prototype.shift", JS::ProfilingCategoryPair::JS,
+ uint32_t(ProfilingStackFrame::Flags::RELEVANT_FOR_JS));
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ // Step 1.
+ RootedObject obj(cx, ToObject(cx, args.thisv()));
+ if (!obj) {
+ return false;
+ }
+
+ // Step 2.
+ uint64_t len;
+ if (!GetLengthProperty(cx, obj, &len)) {
+ return false;
+ }
+
+ // Step 3.
+ if (len == 0) {
+ // Step 3.a.
+ if (!SetLengthProperty(cx, obj, uint32_t(0))) {
+ return false;
+ }
+
+ // Step 3.b.
+ args.rval().setUndefined();
+ return true;
+ }
+
+ uint64_t newlen = len - 1;
+
+ /* Fast paths. */
+ uint64_t startIndex;
+ DenseElementResult result = ArrayShiftDenseKernel(cx, obj, args.rval());
+ if (result != DenseElementResult::Incomplete) {
+ if (result == DenseElementResult::Failure) {
+ return false;
+ }
+
+ if (len <= UINT32_MAX) {
+ return SetLengthProperty(cx, obj, newlen);
+ }
+
+ startIndex = UINT32_MAX - 1;
+ } else {
+ // Steps 4, 9.
+ if (!GetElement(cx, obj, 0, args.rval())) {
+ return false;
+ }
+
+ startIndex = 0;
+ }
+
+ // Steps 5-6.
+ RootedValue value(cx);
+ for (uint64_t i = startIndex; i < newlen; i++) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+ bool hole;
+ if (!HasAndGetElement(cx, obj, i + 1, &hole, &value)) {
+ return false;
+ }
+ if (hole) {
+ if (!DeletePropertyOrThrow(cx, obj, i)) {
+ return false;
+ }
+ } else {
+ if (!SetArrayElement(cx, obj, i, value)) {
+ return false;
+ }
+ }
+ }
+
+ // Step 7.
+ if (!DeletePropertyOrThrow(cx, obj, newlen)) {
+ return false;
+ }
+
+ // Step 8.
+ return SetLengthProperty(cx, obj, newlen);
+}
+
+// ES2017 draft rev 1b0184bc17fc09a8ddcf4aeec9b6d9fcac4eafce
+// 22.1.3.29 Array.prototype.unshift ( ...items )
+static bool array_unshift(JSContext* cx, unsigned argc, Value* vp) {
+ AutoGeckoProfilerEntry pseudoFrame(
+ cx, "Array.prototype.unshift", JS::ProfilingCategoryPair::JS,
+ uint32_t(ProfilingStackFrame::Flags::RELEVANT_FOR_JS));
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ // Step 1.
+ RootedObject obj(cx, ToObject(cx, args.thisv()));
+ if (!obj) {
+ return false;
+ }
+
+ // Step 2.
+ uint64_t length;
+ if (!GetLengthProperty(cx, obj, &length)) {
+ return false;
+ }
+
+ // Steps 3-4.
+ if (args.length() > 0) {
+ bool optimized = false;
+ do {
+ if (length > UINT32_MAX) {
+ break;
+ }
+ if (ObjectMayHaveExtraIndexedProperties(obj)) {
+ break;
+ }
+ NativeObject* nobj = &obj->as<NativeObject>();
+ if (nobj->denseElementsMaybeInIteration()) {
+ break;
+ }
+ if (!nobj->isExtensible()) {
+ break;
+ }
+ if (nobj->is<ArrayObject>() &&
+ !nobj->as<ArrayObject>().lengthIsWritable()) {
+ break;
+ }
+ if (!nobj->tryUnshiftDenseElements(args.length())) {
+ DenseElementResult result =
+ nobj->ensureDenseElements(cx, uint32_t(length), args.length());
+ if (result != DenseElementResult::Success) {
+ if (result == DenseElementResult::Failure) {
+ return false;
+ }
+ MOZ_ASSERT(result == DenseElementResult::Incomplete);
+ break;
+ }
+ if (length > 0) {
+ nobj->moveDenseElements(args.length(), 0, uint32_t(length));
+ }
+ }
+ for (uint32_t i = 0; i < args.length(); i++) {
+ nobj->setDenseElement(i, args[i]);
+ }
+ optimized = true;
+ } while (false);
+
+ if (!optimized) {
+ if (length > 0) {
+ uint64_t last = length;
+ uint64_t upperIndex = last + args.length();
+
+ // Step 4.a.
+ if (upperIndex >= uint64_t(DOUBLE_INTEGRAL_PRECISION_LIMIT)) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_TOO_LONG_ARRAY);
+ return false;
+ }
+
+ // Steps 4.b-c.
+ RootedValue value(cx);
+ do {
+ --last;
+ --upperIndex;
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+ bool hole;
+ if (!HasAndGetElement(cx, obj, last, &hole, &value)) {
+ return false;
+ }
+ if (hole) {
+ if (!DeletePropertyOrThrow(cx, obj, upperIndex)) {
+ return false;
+ }
+ } else {
+ if (!SetArrayElement(cx, obj, upperIndex, value)) {
+ return false;
+ }
+ }
+ } while (last != 0);
+ }
+
+ // Steps 4.d-f.
+ /* Copy from args to the bottom of the array. */
+ if (!SetArrayElements(cx, obj, 0, args.length(), args.array())) {
+ return false;
+ }
+ }
+ }
+
+ // Step 5.
+ uint64_t newlength = length + args.length();
+ if (!SetLengthProperty(cx, obj, newlength)) {
+ return false;
+ }
+
+ // Step 6.
+ /* Follow Perl by returning the new array length. */
+ args.rval().setNumber(double(newlength));
+ return true;
+}
+
+enum class ArrayAccess { Read, Write };
+
+/*
+ * Returns true if this is a dense array whose properties ending at |endIndex|
+ * (exclusive) may be accessed (get, set, delete) directly through its
+ * contiguous vector of elements without fear of getters, setters, etc. along
+ * the prototype chain, or of enumerators requiring notification of
+ * modifications.
+ */
+template <ArrayAccess Access>
+static bool CanOptimizeForDenseStorage(HandleObject arr, uint64_t endIndex) {
+ /* If the desired properties overflow dense storage, we can't optimize. */
+ if (endIndex > UINT32_MAX) {
+ return false;
+ }
+
+ if (Access == ArrayAccess::Read) {
+ /*
+ * Dense storage read access is possible for any packed array as long
+ * as we only access properties within the initialized length. In all
+ * other cases we need to ensure there are no other indexed properties
+ * on this object or on the prototype chain. Callers are required to
+ * clamp the read length, so it doesn't exceed the initialized length.
+ */
+ if (IsPackedArray(arr) &&
+ endIndex <= arr->as<ArrayObject>().getDenseInitializedLength()) {
+ return true;
+ }
+ return !ObjectMayHaveExtraIndexedProperties(arr);
+ }
+
+ /* There's no optimizing possible if it's not an array. */
+ if (!arr->is<ArrayObject>()) {
+ return false;
+ }
+
+ /* If the length is non-writable, always pick the slow path */
+ if (!arr->as<ArrayObject>().lengthIsWritable()) {
+ return false;
+ }
+
+ /* Also pick the slow path if the object is non-extensible. */
+ if (!arr->as<ArrayObject>().isExtensible()) {
+ return false;
+ }
+
+ /* Also pick the slow path if the object is being iterated over. */
+ if (arr->as<ArrayObject>().denseElementsMaybeInIteration()) {
+ return false;
+ }
+
+ /* Or we attempt to write to indices outside the initialized length. */
+ if (endIndex > arr->as<ArrayObject>().getDenseInitializedLength()) {
+ return false;
+ }
+
+ /*
+ * Now watch out for getters and setters along the prototype chain or in
+ * other indexed properties on the object. Packed arrays don't have any
+ * other indexed properties by definition.
+ */
+ return IsPackedArray(arr) || !ObjectMayHaveExtraIndexedProperties(arr);
+}
+
+static ArrayObject* CopyDenseArrayElements(JSContext* cx,
+ HandleNativeObject obj,
+ uint32_t begin, uint32_t count) {
+ size_t initlen = obj->getDenseInitializedLength();
+ MOZ_ASSERT(initlen <= UINT32_MAX,
+ "initialized length shouldn't exceed UINT32_MAX");
+ uint32_t newlength = 0;
+ if (initlen > begin) {
+ newlength = std::min<uint32_t>(initlen - begin, count);
+ }
+
+ ArrayObject* narr = NewDenseFullyAllocatedArray(cx, newlength);
+ if (!narr) {
+ return nullptr;
+ }
+
+ MOZ_ASSERT(count >= narr->length());
+ narr->setLength(count);
+
+ if (newlength > 0) {
+ narr->initDenseElements(obj, begin, newlength);
+ }
+
+ return narr;
+}
+
+static bool CopyArrayElements(JSContext* cx, HandleObject obj, uint64_t begin,
+ uint64_t count, HandleArrayObject result) {
+ MOZ_ASSERT(result->length() == count);
+
+ uint64_t startIndex = 0;
+ RootedValue value(cx);
+
+ // Use dense storage for new indexed properties where possible.
+ {
+ uint32_t index = 0;
+ uint32_t limit = std::min<uint32_t>(count, JSID_INT_MAX);
+ for (; index < limit; index++) {
+ bool hole;
+ if (!CheckForInterrupt(cx) ||
+ !HasAndGetElement(cx, obj, begin + index, &hole, &value)) {
+ return false;
+ }
+
+ if (!hole) {
+ DenseElementResult edResult = result->ensureDenseElements(cx, index, 1);
+ if (edResult != DenseElementResult::Success) {
+ if (edResult == DenseElementResult::Failure) {
+ return false;
+ }
+
+ MOZ_ASSERT(edResult == DenseElementResult::Incomplete);
+ if (!DefineDataElement(cx, result, index, value)) {
+ return false;
+ }
+
+ break;
+ }
+ result->setDenseElement(index, value);
+ }
+ }
+ startIndex = index + 1;
+ }
+
+ // Copy any remaining elements.
+ for (uint64_t i = startIndex; i < count; i++) {
+ bool hole;
+ if (!CheckForInterrupt(cx) ||
+ !HasAndGetElement(cx, obj, begin + i, &hole, &value)) {
+ return false;
+ }
+
+ if (!hole && !DefineArrayElement(cx, result, i, value)) {
+ return false;
+ }
+ }
+ return true;
+}
+
+static bool array_splice_impl(JSContext* cx, unsigned argc, Value* vp,
+ bool returnValueIsUsed) {
+ AutoGeckoProfilerEntry pseudoFrame(
+ cx, "Array.prototype.splice", JS::ProfilingCategoryPair::JS,
+ uint32_t(ProfilingStackFrame::Flags::RELEVANT_FOR_JS));
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ /* Step 1. */
+ RootedObject obj(cx, ToObject(cx, args.thisv()));
+ if (!obj) {
+ return false;
+ }
+
+ /* Step 2. */
+ uint64_t len;
+ if (!GetLengthProperty(cx, obj, &len)) {
+ return false;
+ }
+
+ /* Step 3. */
+ double relativeStart;
+ if (!ToInteger(cx, args.get(0), &relativeStart)) {
+ return false;
+ }
+
+ /* Step 4. */
+ uint64_t actualStart;
+ if (relativeStart < 0) {
+ actualStart = std::max(len + relativeStart, 0.0);
+ } else {
+ actualStart = std::min(relativeStart, double(len));
+ }
+
+ /* Step 5. */
+ uint64_t actualDeleteCount;
+ if (args.length() == 0) {
+ /* Step 5.b. */
+ actualDeleteCount = 0;
+ } else if (args.length() == 1) {
+ /* Step 6.b. */
+ actualDeleteCount = len - actualStart;
+ } else {
+ /* Steps 7.b. */
+ double deleteCountDouble;
+ if (!ToInteger(cx, args[1], &deleteCountDouble)) {
+ return false;
+ }
+
+ /* Step 7.c. */
+ actualDeleteCount =
+ std::min(std::max(deleteCountDouble, 0.0), double(len - actualStart));
+
+ /* Step 8. */
+ uint32_t insertCount = args.length() - 2;
+ if (len + insertCount - actualDeleteCount >=
+ DOUBLE_INTEGRAL_PRECISION_LIMIT) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_TOO_LONG_ARRAY);
+ return false;
+ }
+ }
+
+ MOZ_ASSERT(actualStart + actualDeleteCount <= len);
+
+ RootedObject arr(cx);
+ if (IsArraySpecies(cx, obj)) {
+ if (actualDeleteCount > UINT32_MAX) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_BAD_ARRAY_LENGTH);
+ return false;
+ }
+ uint32_t count = uint32_t(actualDeleteCount);
+
+ if (CanOptimizeForDenseStorage<ArrayAccess::Read>(obj,
+ actualStart + count)) {
+ MOZ_ASSERT(actualStart <= UINT32_MAX,
+ "if actualStart + count <= UINT32_MAX, then actualStart <= "
+ "UINT32_MAX");
+ if (returnValueIsUsed) {
+ /* Steps 9-12. */
+ arr = CopyDenseArrayElements(cx, obj.as<NativeObject>(),
+ uint32_t(actualStart), count);
+ if (!arr) {
+ return false;
+ }
+ }
+ } else {
+ /* Step 9. */
+ arr = NewDenseFullyAllocatedArray(cx, count);
+ if (!arr) {
+ return false;
+ }
+
+ /* Steps 10-11. */
+ if (!CopyArrayElements(cx, obj, actualStart, count,
+ arr.as<ArrayObject>())) {
+ return false;
+ }
+
+ /* Step 12 (implicit). */
+ }
+ } else {
+ /* Steps 9. */
+ if (!ArraySpeciesCreate(cx, obj, actualDeleteCount, &arr)) {
+ return false;
+ }
+
+ /* Steps 10, 11, 11.d. */
+ RootedValue fromValue(cx);
+ for (uint64_t k = 0; k < actualDeleteCount; k++) {
+ /* Step 11.a (implicit). */
+
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ /* Steps 11.b, 11.c.i. */
+ bool hole;
+ if (!HasAndGetElement(cx, obj, actualStart + k, &hole, &fromValue)) {
+ return false;
+ }
+
+ /* Step 11.c. */
+ if (!hole) {
+ /* Step 11.c.ii. */
+ if (!DefineArrayElement(cx, arr, k, fromValue)) {
+ return false;
+ }
+ }
+ }
+
+ /* Step 12. */
+ if (!SetLengthProperty(cx, arr, actualDeleteCount)) {
+ return false;
+ }
+ }
+
+ /* Step 14. */
+ uint32_t itemCount = (args.length() >= 2) ? (args.length() - 2) : 0;
+ uint64_t finalLength = len - actualDeleteCount + itemCount;
+
+ if (itemCount < actualDeleteCount) {
+ /* Step 15: the array is being shrunk. */
+ uint64_t sourceIndex = actualStart + actualDeleteCount;
+ uint64_t targetIndex = actualStart + itemCount;
+
+ if (CanOptimizeForDenseStorage<ArrayAccess::Write>(obj, len)) {
+ MOZ_ASSERT(sourceIndex <= len && targetIndex <= len && len <= UINT32_MAX,
+ "sourceIndex and targetIndex are uint32 array indices");
+ MOZ_ASSERT(finalLength < len, "finalLength is strictly less than len");
+ MOZ_ASSERT(obj->isNative());
+
+ /* Steps 15.a-b. */
+ HandleArrayObject arr = obj.as<ArrayObject>();
+ if (targetIndex != 0 || !arr->tryShiftDenseElements(sourceIndex)) {
+ arr->moveDenseElements(uint32_t(targetIndex), uint32_t(sourceIndex),
+ uint32_t(len - sourceIndex));
+ }
+
+ /* Steps 15.c-d. */
+ SetInitializedLength(cx, arr, finalLength);
+ } else {
+ /*
+ * This is all very slow if the length is very large. We don't yet
+ * have the ability to iterate in sorted order, so we just do the
+ * pessimistic thing and let CheckForInterrupt handle the
+ * fallout.
+ */
+
+ /* Steps 15.a-b. */
+ RootedValue fromValue(cx);
+ for (uint64_t from = sourceIndex, to = targetIndex; from < len;
+ from++, to++) {
+ /* Steps 15.b.i-ii (implicit). */
+
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ /* Steps 15.b.iii, 15.b.iv.1. */
+ bool hole;
+ if (!HasAndGetElement(cx, obj, from, &hole, &fromValue)) {
+ return false;
+ }
+
+ /* Steps 15.b.iv. */
+ if (hole) {
+ /* Steps 15.b.v.1. */
+ if (!DeletePropertyOrThrow(cx, obj, to)) {
+ return false;
+ }
+ } else {
+ /* Step 15.b.iv.2. */
+ if (!SetArrayElement(cx, obj, to, fromValue)) {
+ return false;
+ }
+ }
+ }
+
+ /* Steps 15.c-d. */
+ if (!DeletePropertiesOrThrow(cx, obj, len, finalLength)) {
+ return false;
+ }
+ }
+ } else if (itemCount > actualDeleteCount) {
+ MOZ_ASSERT(actualDeleteCount <= UINT32_MAX);
+ uint32_t deleteCount = uint32_t(actualDeleteCount);
+
+ /* Step 16. */
+
+ // Fast path for when we can simply extend and move the dense elements.
+ auto extendElements = [len, itemCount, deleteCount](JSContext* cx,
+ HandleObject obj) {
+ if (!obj->is<ArrayObject>()) {
+ return DenseElementResult::Incomplete;
+ }
+ if (len > UINT32_MAX) {
+ return DenseElementResult::Incomplete;
+ }
+
+ // Ensure there are no getters/setters or other extra indexed properties.
+ if (ObjectMayHaveExtraIndexedProperties(obj)) {
+ return DenseElementResult::Incomplete;
+ }
+
+ // Watch out for arrays with non-writable length or non-extensible arrays.
+ // In these cases `splice` may have to throw an exception so we let the
+ // slow path handle it. We also have to ensure we maintain the
+ // |capacity <= initializedLength| invariant for such objects. See
+ // NativeObject::shrinkCapacityToInitializedLength.
+ HandleArrayObject arr = obj.as<ArrayObject>();
+ if (!arr->lengthIsWritable() || !arr->isExtensible()) {
+ return DenseElementResult::Incomplete;
+ }
+
+ // Also use the slow path if there might be an active for-in iterator so
+ // that we don't have to worry about suppressing deleted properties.
+ if (arr->denseElementsMaybeInIteration()) {
+ return DenseElementResult::Incomplete;
+ }
+
+ return arr->ensureDenseElements(cx, uint32_t(len),
+ itemCount - deleteCount);
+ };
+
+ DenseElementResult res = extendElements(cx, obj);
+ if (res == DenseElementResult::Failure) {
+ return false;
+ }
+ if (res == DenseElementResult::Success) {
+ MOZ_ASSERT(finalLength <= UINT32_MAX);
+ MOZ_ASSERT((actualStart + actualDeleteCount) <= len && len <= UINT32_MAX,
+ "start and deleteCount are uint32 array indices");
+ MOZ_ASSERT(actualStart + itemCount <= UINT32_MAX,
+ "can't overflow because |len - actualDeleteCount + itemCount "
+ "<= UINT32_MAX| "
+ "and |actualStart <= len - actualDeleteCount| are both true");
+ uint32_t start = uint32_t(actualStart);
+ uint32_t length = uint32_t(len);
+
+ HandleArrayObject arr = obj.as<ArrayObject>();
+ arr->moveDenseElements(start + itemCount, start + deleteCount,
+ length - (start + deleteCount));
+
+ /* Steps 16.a-b. */
+ SetInitializedLength(cx, arr, finalLength);
+ } else {
+ MOZ_ASSERT(res == DenseElementResult::Incomplete);
+
+ RootedValue fromValue(cx);
+ for (uint64_t k = len - actualDeleteCount; k > actualStart; k--) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ /* Step 16.b.i. */
+ uint64_t from = k + actualDeleteCount - 1;
+
+ /* Step 16.b.ii. */
+ uint64_t to = k + itemCount - 1;
+
+ /* Steps 16.b.iii, 16.b.iv.1. */
+ bool hole;
+ if (!HasAndGetElement(cx, obj, from, &hole, &fromValue)) {
+ return false;
+ }
+
+ /* Steps 16.b.iv. */
+ if (hole) {
+ /* Step 16.b.v.1. */
+ if (!DeletePropertyOrThrow(cx, obj, to)) {
+ return false;
+ }
+ } else {
+ /* Step 16.b.iv.2. */
+ if (!SetArrayElement(cx, obj, to, fromValue)) {
+ return false;
+ }
+ }
+ }
+ }
+ }
+
+ /* Step 13 (reordered). */
+ Value* items = args.array() + 2;
+
+ /* Steps 17-18. */
+ if (!SetArrayElements(cx, obj, actualStart, itemCount, items)) {
+ return false;
+ }
+
+ /* Step 19. */
+ if (!SetLengthProperty(cx, obj, finalLength)) {
+ return false;
+ }
+
+ /* Step 20. */
+ if (returnValueIsUsed) {
+ args.rval().setObject(*arr);
+ }
+
+ return true;
+}
+
+/* ES 2016 draft Mar 25, 2016 22.1.3.26. */
+static bool array_splice(JSContext* cx, unsigned argc, Value* vp) {
+ return array_splice_impl(cx, argc, vp, true);
+}
+
+static bool array_splice_noRetVal(JSContext* cx, unsigned argc, Value* vp) {
+ return array_splice_impl(cx, argc, vp, false);
+}
+
+struct SortComparatorIndexes {
+ bool operator()(uint32_t a, uint32_t b, bool* lessOrEqualp) {
+ *lessOrEqualp = (a <= b);
+ return true;
+ }
+};
+
+// Returns all indexed properties in the range [begin, end) found on |obj| or
+// its proto chain. This function does not handle proxies, objects with
+// resolve/lookupProperty hooks or indexed getters, as those can introduce
+// new properties. In those cases, *success is set to |false|.
+static bool GetIndexedPropertiesInRange(JSContext* cx, HandleObject obj,
+ uint64_t begin, uint64_t end,
+ Vector<uint32_t>& indexes,
+ bool* success) {
+ *success = false;
+
+ // TODO: Add IdIsIndex with support for large indices.
+ if (end > UINT32_MAX) {
+ return true;
+ }
+ MOZ_ASSERT(begin <= UINT32_MAX);
+
+ // First, look for proxies or class hooks that can introduce extra
+ // properties.
+ JSObject* pobj = obj;
+ do {
+ if (!pobj->isNative() || pobj->getClass()->getResolve() ||
+ pobj->getOpsLookupProperty()) {
+ return true;
+ }
+ } while ((pobj = pobj->staticPrototype()));
+
+ // Collect indexed property names.
+ pobj = obj;
+ do {
+ // Append dense elements.
+ NativeObject* nativeObj = &pobj->as<NativeObject>();
+ uint32_t initLen = nativeObj->getDenseInitializedLength();
+ for (uint32_t i = begin; i < initLen && i < end; i++) {
+ if (nativeObj->getDenseElement(i).isMagic(JS_ELEMENTS_HOLE)) {
+ continue;
+ }
+ if (!indexes.append(i)) {
+ return false;
+ }
+ }
+
+ // Append typed array elements.
+ if (nativeObj->is<TypedArrayObject>()) {
+ size_t len = nativeObj->as<TypedArrayObject>().length().get();
+ for (uint32_t i = begin; i < len && i < end; i++) {
+ if (!indexes.append(i)) {
+ return false;
+ }
+ }
+ }
+
+ // Append sparse elements.
+ if (nativeObj->isIndexed()) {
+ Shape::Range<NoGC> r(nativeObj->lastProperty());
+ for (; !r.empty(); r.popFront()) {
+ Shape& shape = r.front();
+ jsid id = shape.propid();
+ uint32_t i;
+ if (!IdIsIndex(id, &i)) {
+ continue;
+ }
+
+ if (!(begin <= i && i < end)) {
+ continue;
+ }
+
+ // Watch out for getters, they can add new properties.
+ if (!shape.hasDefaultGetter()) {
+ return true;
+ }
+
+ if (!indexes.append(i)) {
+ return false;
+ }
+ }
+ }
+ } while ((pobj = pobj->staticPrototype()));
+
+ // Sort the indexes.
+ Vector<uint32_t> tmp(cx);
+ size_t n = indexes.length();
+ if (!tmp.resize(n)) {
+ return false;
+ }
+ if (!MergeSort(indexes.begin(), n, tmp.begin(), SortComparatorIndexes())) {
+ return false;
+ }
+
+ // Remove duplicates.
+ if (!indexes.empty()) {
+ uint32_t last = 0;
+ for (size_t i = 1, len = indexes.length(); i < len; i++) {
+ uint32_t elem = indexes[i];
+ if (indexes[last] != elem) {
+ last++;
+ indexes[last] = elem;
+ }
+ }
+ if (!indexes.resize(last + 1)) {
+ return false;
+ }
+ }
+
+ *success = true;
+ return true;
+}
+
+static bool SliceSparse(JSContext* cx, HandleObject obj, uint64_t begin,
+ uint64_t end, HandleArrayObject result) {
+ MOZ_ASSERT(begin <= end);
+
+ Vector<uint32_t> indexes(cx);
+ bool success;
+ if (!GetIndexedPropertiesInRange(cx, obj, begin, end, indexes, &success)) {
+ return false;
+ }
+
+ if (!success) {
+ return CopyArrayElements(cx, obj, begin, end - begin, result);
+ }
+
+ MOZ_ASSERT(end <= UINT32_MAX,
+ "indices larger than UINT32_MAX should be rejected by "
+ "GetIndexedPropertiesInRange");
+
+ RootedValue value(cx);
+ for (uint32_t index : indexes) {
+ MOZ_ASSERT(begin <= index && index < end);
+
+ bool hole;
+ if (!HasAndGetElement(cx, obj, index, &hole, &value)) {
+ return false;
+ }
+
+ if (!hole &&
+ !DefineDataElement(cx, result, index - uint32_t(begin), value)) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static JSObject* SliceArguments(JSContext* cx, Handle<ArgumentsObject*> argsobj,
+ uint32_t begin, uint32_t count) {
+ MOZ_ASSERT(!argsobj->hasOverriddenLength() &&
+ !argsobj->isAnyElementDeleted());
+ MOZ_ASSERT(begin + count <= argsobj->initialLength());
+
+ ArrayObject* result = NewDenseFullyAllocatedArray(cx, count);
+ if (!result) {
+ return nullptr;
+ }
+ result->setDenseInitializedLength(count);
+
+ for (uint32_t index = 0; index < count; index++) {
+ const Value& v = argsobj->element(begin + index);
+ result->initDenseElement(index, v);
+ }
+ return result;
+}
+
+template <typename T, typename ArrayLength>
+static inline ArrayLength NormalizeSliceTerm(T value, ArrayLength length) {
+ if (value < 0) {
+ value += length;
+ if (value < 0) {
+ return 0;
+ }
+ } else if (double(value) > double(length)) {
+ return length;
+ }
+ return ArrayLength(value);
+}
+
+static bool ArraySliceOrdinary(JSContext* cx, HandleObject obj, uint64_t begin,
+ uint64_t end, MutableHandleValue rval) {
+ if (begin > end) {
+ begin = end;
+ }
+
+ if ((end - begin) > UINT32_MAX) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_BAD_ARRAY_LENGTH);
+ return false;
+ }
+ uint32_t count = uint32_t(end - begin);
+
+ if (CanOptimizeForDenseStorage<ArrayAccess::Read>(obj, end)) {
+ MOZ_ASSERT(begin <= UINT32_MAX,
+ "if end <= UINT32_MAX, then begin <= UINT32_MAX");
+ JSObject* narr = CopyDenseArrayElements(cx, obj.as<NativeObject>(),
+ uint32_t(begin), count);
+ if (!narr) {
+ return false;
+ }
+
+ rval.setObject(*narr);
+ return true;
+ }
+
+ if (obj->is<ArgumentsObject>()) {
+ Handle<ArgumentsObject*> argsobj = obj.as<ArgumentsObject>();
+ if (!argsobj->hasOverriddenLength() && !argsobj->isAnyElementDeleted()) {
+ MOZ_ASSERT(begin <= UINT32_MAX, "begin is limited by |argsobj|'s length");
+ JSObject* narr = SliceArguments(cx, argsobj, uint32_t(begin), count);
+ if (!narr) {
+ return false;
+ }
+
+ rval.setObject(*narr);
+ return true;
+ }
+ }
+
+ RootedArrayObject narr(cx, NewDensePartlyAllocatedArray(cx, count));
+ if (!narr) {
+ return false;
+ }
+
+ if (end <= UINT32_MAX) {
+ if (js::GetElementsOp op = obj->getOpsGetElements()) {
+ ElementAdder adder(cx, narr, count,
+ ElementAdder::CheckHasElemPreserveHoles);
+ if (!op(cx, obj, uint32_t(begin), uint32_t(end), &adder)) {
+ return false;
+ }
+
+ rval.setObject(*narr);
+ return true;
+ }
+ }
+
+ if (obj->isNative() && obj->as<NativeObject>().isIndexed() && count > 1000) {
+ if (!SliceSparse(cx, obj, begin, end, narr)) {
+ return false;
+ }
+ } else {
+ if (!CopyArrayElements(cx, obj, begin, count, narr)) {
+ return false;
+ }
+ }
+
+ rval.setObject(*narr);
+ return true;
+}
+
+/* ES 2016 draft Mar 25, 2016 22.1.3.23. */
+bool js::array_slice(JSContext* cx, unsigned argc, Value* vp) {
+ AutoGeckoProfilerEntry pseudoFrame(
+ cx, "Array.prototype.slice", JS::ProfilingCategoryPair::JS,
+ uint32_t(ProfilingStackFrame::Flags::RELEVANT_FOR_JS));
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ /* Step 1. */
+ RootedObject obj(cx, ToObject(cx, args.thisv()));
+ if (!obj) {
+ return false;
+ }
+
+ /* Step 2. */
+ uint64_t length;
+ if (!GetLengthProperty(cx, obj, &length)) {
+ return false;
+ }
+
+ uint64_t k = 0;
+ uint64_t final = length;
+ if (args.length() > 0) {
+ double d;
+ /* Step 3. */
+ if (!ToInteger(cx, args[0], &d)) {
+ return false;
+ }
+
+ /* Step 4. */
+ k = NormalizeSliceTerm(d, length);
+
+ if (args.hasDefined(1)) {
+ /* Step 5. */
+ if (!ToInteger(cx, args[1], &d)) {
+ return false;
+ }
+
+ /* Step 6. */
+ final = NormalizeSliceTerm(d, length);
+ }
+ }
+
+ if (IsArraySpecies(cx, obj)) {
+ /* Steps 7-12: Optimized for ordinary array. */
+ return ArraySliceOrdinary(cx, obj, k, final, args.rval());
+ }
+
+ /* Step 7. */
+ uint64_t count = final > k ? final - k : 0;
+
+ /* Step 8. */
+ RootedObject arr(cx);
+ if (!ArraySpeciesCreate(cx, obj, count, &arr)) {
+ return false;
+ }
+
+ /* Step 9. */
+ uint64_t n = 0;
+
+ /* Step 10. */
+ RootedValue kValue(cx);
+ while (k < final) {
+ if (!CheckForInterrupt(cx)) {
+ return false;
+ }
+
+ /* Steps 10.a-b, and 10.c.i. */
+ bool kNotPresent;
+ if (!HasAndGetElement(cx, obj, k, &kNotPresent, &kValue)) {
+ return false;
+ }
+
+ /* Step 10.c. */
+ if (!kNotPresent) {
+ /* Steps 10.c.ii. */
+ if (!DefineArrayElement(cx, arr, n, kValue)) {
+ return false;
+ }
+ }
+ /* Step 10.d. */
+ k++;
+
+ /* Step 10.e. */
+ n++;
+ }
+
+ /* Step 11. */
+ if (!SetLengthProperty(cx, arr, n)) {
+ return false;
+ }
+
+ /* Step 12. */
+ args.rval().setObject(*arr);
+ return true;
+}
+
+static bool ArraySliceDenseKernel(JSContext* cx, ArrayObject* arr,
+ int32_t beginArg, int32_t endArg,
+ ArrayObject* result) {
+ uint32_t length = arr->length();
+
+ uint32_t begin = NormalizeSliceTerm(beginArg, length);
+ uint32_t end = NormalizeSliceTerm(endArg, length);
+
+ if (begin > end) {
+ begin = end;
+ }
+
+ uint32_t count = end - begin;
+ size_t initlen = arr->getDenseInitializedLength();
+ if (initlen > begin) {
+ uint32_t newlength = std::min<uint32_t>(initlen - begin, count);
+ if (newlength > 0) {
+ if (!result->ensureElements(cx, newlength)) {
+ return false;
+ }
+ result->initDenseElements(arr, begin, newlength);
+ }
+ }
+
+ MOZ_ASSERT(count >= result->length());
+ result->setLength(count);
+
+ return true;
+}
+
+JSObject* js::ArraySliceDense(JSContext* cx, HandleObject obj, int32_t begin,
+ int32_t end, HandleObject result) {
+ MOZ_ASSERT(IsPackedArray(obj));
+
+ if (result && IsArraySpecies(cx, obj)) {
+ if (!ArraySliceDenseKernel(cx, &obj->as<ArrayObject>(), begin, end,
+ &result->as<ArrayObject>())) {
+ return nullptr;
+ }
+ return result;
+ }
+
+ // Slower path if the JIT wasn't able to allocate an object inline.
+ JS::RootedValueArray<4> argv(cx);
+ argv[0].setUndefined();
+ argv[1].setObject(*obj);
+ argv[2].setInt32(begin);
+ argv[3].setInt32(end);
+ if (!array_slice(cx, 2, argv.begin())) {
+ return nullptr;
+ }
+ return &argv[0].toObject();
+}
+
+static bool array_isArray(JSContext* cx, unsigned argc, Value* vp) {
+ CallArgs args = CallArgsFromVp(argc, vp);
+ bool isArray = false;
+ if (args.get(0).isObject()) {
+ RootedObject obj(cx, &args[0].toObject());
+ if (!IsArray(cx, obj, &isArray)) {
+ return false;
+ }
+ }
+ args.rval().setBoolean(isArray);
+ return true;
+}
+
+static bool ArrayFromCallArgs(JSContext* cx, CallArgs& args,
+ HandleObject proto = nullptr) {
+ ArrayObject* obj =
+ NewDenseCopiedArray(cx, args.length(), args.array(), proto);
+ if (!obj) {
+ return false;
+ }
+
+ args.rval().setObject(*obj);
+ return true;
+}
+
+static bool array_of(JSContext* cx, unsigned argc, Value* vp) {
+ CallArgs args = CallArgsFromVp(argc, vp);
+
+ bool isArrayConstructor =
+ IsArrayConstructor(args.thisv()) &&
+ args.thisv().toObject().nonCCWRealm() == cx->realm();
+
+ if (isArrayConstructor || !IsConstructor(args.thisv())) {
+ // isArrayConstructor will usually be true in practice. This is the most
+ // common path.
+ return ArrayFromCallArgs(cx, args);
+ }
+
+ // Step 4.
+ RootedObject obj(cx);
+ {
+ FixedConstructArgs<1> cargs(cx);
+
+ cargs[0].setNumber(args.length());
+
+ if (!Construct(cx, args.thisv(), cargs, args.thisv(), &obj)) {
+ return false;
+ }
+ }
+
+ // Step 8.
+ for (unsigned k = 0; k < args.length(); k++) {
+ if (!DefineDataElement(cx, obj, k, args[k])) {
+ return false;
+ }
+ }
+
+ // Steps 9-10.
+ if (!SetLengthProperty(cx, obj, args.length())) {
+ return false;
+ }
+
+ // Step 11.
+ args.rval().setObject(*obj);
+ return true;
+}
+
+static const JSJitInfo array_splice_info = {
+ {(JSJitGetterOp)array_splice_noRetVal},
+ {0}, /* unused */
+ {0}, /* unused */
+ JSJitInfo::IgnoresReturnValueNative,
+ JSJitInfo::AliasEverything,
+ JSVAL_TYPE_UNDEFINED,
+};
+
+static const JSFunctionSpec array_methods[] = {
+ JS_FN(js_toSource_str, array_toSource, 0, 0),
+ JS_SELF_HOSTED_FN(js_toString_str, "ArrayToString", 0, 0),
+ JS_FN(js_toLocaleString_str, array_toLocaleString, 0, 0),
+
+ /* Perl-ish methods. */
+ JS_INLINABLE_FN("join", array_join, 1, 0, ArrayJoin),
+ JS_FN("reverse", array_reverse, 0, 0),
+ JS_SELF_HOSTED_FN("sort", "ArraySort", 1, 0),
+ JS_INLINABLE_FN("push", array_push, 1, 0, ArrayPush),
+ JS_INLINABLE_FN("pop", array_pop, 0, 0, ArrayPop),
+ JS_INLINABLE_FN("shift", array_shift, 0, 0, ArrayShift),
+ JS_FN("unshift", array_unshift, 1, 0),
+ JS_FNINFO("splice", array_splice, &array_splice_info, 2, 0),
+
+ /* Pythonic sequence methods. */
+ JS_SELF_HOSTED_FN("concat", "ArrayConcat", 1, 0),
+ JS_INLINABLE_FN("slice", array_slice, 2, 0, ArraySlice),
+
+ JS_SELF_HOSTED_FN("lastIndexOf", "ArrayLastIndexOf", 1, 0),
+ JS_SELF_HOSTED_FN("indexOf", "ArrayIndexOf", 1, 0),
+ JS_SELF_HOSTED_FN("forEach", "ArrayForEach", 1, 0),
+ JS_SELF_HOSTED_FN("map", "ArrayMap", 1, 0),
+ JS_SELF_HOSTED_FN("filter", "ArrayFilter", 1, 0),
+ JS_SELF_HOSTED_FN("reduce", "ArrayReduce", 1, 0),
+ JS_SELF_HOSTED_FN("reduceRight", "ArrayReduceRight", 1, 0),
+ JS_SELF_HOSTED_FN("some", "ArraySome", 1, 0),
+ JS_SELF_HOSTED_FN("every", "ArrayEvery", 1, 0),
+
+ /* ES6 additions */
+ JS_SELF_HOSTED_FN("find", "ArrayFind", 1, 0),
+ JS_SELF_HOSTED_FN("findIndex", "ArrayFindIndex", 1, 0),
+ JS_SELF_HOSTED_FN("copyWithin", "ArrayCopyWithin", 3, 0),
+
+ JS_SELF_HOSTED_FN("fill", "ArrayFill", 3, 0),
+
+ JS_SELF_HOSTED_SYM_FN(iterator, "$ArrayValues", 0, 0),
+ JS_SELF_HOSTED_FN("entries", "ArrayEntries", 0, 0),
+ JS_SELF_HOSTED_FN("keys", "ArrayKeys", 0, 0),
+ JS_SELF_HOSTED_FN("values", "$ArrayValues", 0, 0),
+
+ /* ES7 additions */
+ JS_SELF_HOSTED_FN("includes", "ArrayIncludes", 2, 0),
+
+ /* ES2020 */
+ JS_SELF_HOSTED_FN("flatMap", "ArrayFlatMap", 1, 0),
+ JS_SELF_HOSTED_FN("flat", "ArrayFlat", 0, 0),
+
+/* Proposal */
+#ifdef NIGHTLY_BUILD
+ JS_SELF_HOSTED_FN("at", "ArrayAt", 1, 0),
+#endif
+
+ JS_FS_END};
+
+static const JSFunctionSpec array_static_methods[] = {
+ JS_INLINABLE_FN("isArray", array_isArray, 1, 0, ArrayIsArray),
+ JS_SELF_HOSTED_FN("from", "ArrayFrom", 3, 0), JS_FN("of", array_of, 0, 0),
+
+ JS_FS_END};
+
+const JSPropertySpec array_static_props[] = {
+ JS_SELF_HOSTED_SYM_GET(species, "$ArraySpecies", 0), JS_PS_END};
+
+static inline bool ArrayConstructorImpl(JSContext* cx, CallArgs& args,
+ bool isConstructor) {
+ RootedObject proto(cx);
+ if (isConstructor) {
+ if (!GetPrototypeFromBuiltinConstructor(cx, args, JSProto_Array, &proto)) {
+ return false;
+ }
+ } else {
+ // We're emulating |new Array(n)| with |std_Array(n)| in self-hosted JS,
+ // and the proto should be %ArrayPrototype% regardless of the callee.
+ proto = GlobalObject::getOrCreateArrayPrototype(cx, cx->global());
+ if (!proto) {
+ return false;
+ }
+ }
+
+ if (args.length() != 1 || !args[0].isNumber()) {
+ return ArrayFromCallArgs(cx, args, proto);
+ }
+
+ uint32_t length;
+ if (args[0].isInt32()) {
+ int32_t i = args[0].toInt32();
+ if (i < 0) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_BAD_ARRAY_LENGTH);
+ return false;
+ }
+ length = uint32_t(i);
+ } else {
+ double d = args[0].toDouble();
+ length = ToUint32(d);
+ if (d != double(length)) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_BAD_ARRAY_LENGTH);
+ return false;
+ }
+ }
+
+ ArrayObject* obj = NewDensePartlyAllocatedArray(cx, length, proto);
+ if (!obj) {
+ return false;
+ }
+
+ args.rval().setObject(*obj);
+ return true;
+}
+
+/* ES5 15.4.2 */
+bool js::ArrayConstructor(JSContext* cx, unsigned argc, Value* vp) {
+ CallArgs args = CallArgsFromVp(argc, vp);
+ return ArrayConstructorImpl(cx, args, /* isConstructor = */ true);
+}
+
+bool js::array_construct(JSContext* cx, unsigned argc, Value* vp) {
+ CallArgs args = CallArgsFromVp(argc, vp);
+ MOZ_ASSERT(!args.isConstructing());
+ MOZ_ASSERT(args.length() == 1);
+ MOZ_ASSERT(args[0].isNumber());
+ return ArrayConstructorImpl(cx, args, /* isConstructor = */ false);
+}
+
+ArrayObject* js::ArrayConstructorOneArg(JSContext* cx,
+ HandleArrayObject templateObject,
+ int32_t lengthInt) {
+ // JIT code can call this with a template object from a different realm when
+ // calling another realm's Array constructor.
+ Maybe<AutoRealm> ar;
+ if (cx->realm() != templateObject->realm()) {
+ MOZ_ASSERT(cx->compartment() == templateObject->compartment());
+ ar.emplace(cx, templateObject);
+ }
+
+ if (lengthInt < 0) {
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_BAD_ARRAY_LENGTH);
+ return nullptr;
+ }
+
+ uint32_t length = uint32_t(lengthInt);
+ ArrayObject* res = NewDensePartlyAllocatedArray(cx, length);
+ MOZ_ASSERT_IF(res, res->realm() == templateObject->realm());
+ return res;
+}
+
+static JSObject* CreateArrayPrototype(JSContext* cx, JSProtoKey key) {
+ MOZ_ASSERT(key == JSProto_Array);
+ RootedObject proto(
+ cx, GlobalObject::getOrCreateObjectPrototype(cx, cx->global()));
+ if (!proto) {
+ return nullptr;
+ }
+
+ RootedObjectGroup group(cx,
+ ObjectGroup::defaultNewGroup(cx, &ArrayObject::class_,
+ TaggedProto(proto)));
+ if (!group) {
+ return nullptr;
+ }
+
+ RootedShape shape(cx, EmptyShape::getInitialShape(cx, &ArrayObject::class_,
+ TaggedProto(proto),
+ gc::AllocKind::OBJECT0));
+ if (!shape) {
+ return nullptr;
+ }
+
+ AutoSetNewObjectMetadata metadata(cx);
+ RootedArrayObject arrayProto(
+ cx, ArrayObject::createArray(cx, gc::AllocKind::OBJECT4, gc::TenuredHeap,
+ shape, group, 0, metadata));
+ if (!arrayProto || !JSObject::setDelegate(cx, arrayProto) ||
+ !AddLengthProperty(cx, arrayProto)) {
+ return nullptr;
+ }
+
+ return arrayProto;
+}
+
+static bool array_proto_finish(JSContext* cx, JS::HandleObject ctor,
+ JS::HandleObject proto) {
+ // Add Array.prototype[@@unscopables]. ECMA-262 draft (2016 Mar 19) 22.1.3.32.
+ RootedObject unscopables(
+ cx, NewTenuredObjectWithGivenProto<PlainObject>(cx, nullptr));
+ if (!unscopables) {
+ return false;
+ }
+
+ RootedValue value(cx, BooleanValue(true));
+#ifdef NIGHTLY_BUILD
+ if (!DefineDataProperty(cx, unscopables, cx->names().at, value)) {
+ return false;
+ }
+#endif
+
+ if (!DefineDataProperty(cx, unscopables, cx->names().copyWithin, value) ||
+ !DefineDataProperty(cx, unscopables, cx->names().entries, value) ||
+ !DefineDataProperty(cx, unscopables, cx->names().fill, value) ||
+ !DefineDataProperty(cx, unscopables, cx->names().find, value) ||
+ !DefineDataProperty(cx, unscopables, cx->names().findIndex, value) ||
+ !DefineDataProperty(cx, unscopables, cx->names().flat, value) ||
+ !DefineDataProperty(cx, unscopables, cx->names().flatMap, value) ||
+ !DefineDataProperty(cx, unscopables, cx->names().includes, value) ||
+ !DefineDataProperty(cx, unscopables, cx->names().keys, value) ||
+ !DefineDataProperty(cx, unscopables, cx->names().values, value)) {
+ return false;
+ }
+
+ RootedId id(cx, SYMBOL_TO_JSID(
+ cx->wellKnownSymbols().get(JS::SymbolCode::unscopables)));
+ value.setObject(*unscopables);
+ return DefineDataProperty(cx, proto, id, value, JSPROP_READONLY);
+}
+
+static const JSClassOps ArrayObjectClassOps = {
+ array_addProperty, // addProperty
+ nullptr, // delProperty
+ nullptr, // enumerate
+ nullptr, // newEnumerate
+ nullptr, // resolve
+ nullptr, // mayResolve
+ nullptr, // finalize
+ nullptr, // call
+ nullptr, // hasInstance
+ nullptr, // construct
+ nullptr, // trace
+};
+
+static const ClassSpec ArrayObjectClassSpec = {
+ GenericCreateConstructor<ArrayConstructor, 1, gc::AllocKind::FUNCTION,
+ &jit::JitInfo_Array>,
+ CreateArrayPrototype,
+ array_static_methods,
+ array_static_props,
+ array_methods,
+ nullptr,
+ array_proto_finish};
+
+const JSClass ArrayObject::class_ = {
+ "Array",
+ JSCLASS_HAS_CACHED_PROTO(JSProto_Array) | JSCLASS_DELAY_METADATA_BUILDER,
+ &ArrayObjectClassOps, &ArrayObjectClassSpec};
+
+/*
+ * Array allocation functions.
+ */
+
+static inline bool EnsureNewArrayElements(JSContext* cx, ArrayObject* obj,
+ uint32_t length) {
+ /*
+ * If ensureElements creates dynamically allocated slots, then having
+ * fixedSlots is a waste.
+ */
+ DebugOnly<uint32_t> cap = obj->getDenseCapacity();
+
+ if (!obj->ensureElements(cx, length)) {
+ return false;
+ }
+
+ MOZ_ASSERT_IF(cap, !obj->hasDynamicElements());
+
+ return true;
+}
+
+template <uint32_t maxLength>
+static MOZ_ALWAYS_INLINE ArrayObject* NewArray(JSContext* cx, uint32_t length,
+ HandleObject protoArg,
+ NewObjectKind newKind) {
+ gc::AllocKind allocKind = GuessArrayGCKind(length);
+ MOZ_ASSERT(CanChangeToBackgroundAllocKind(allocKind, &ArrayObject::class_));
+ allocKind = ForegroundToBackgroundAllocKind(allocKind);
+
+ RootedObject proto(cx, protoArg);
+ if (!proto) {
+ proto = GlobalObject::getOrCreateArrayPrototype(cx, cx->global());
+ if (!proto) {
+ return nullptr;
+ }
+ }
+
+ Rooted<TaggedProto> taggedProto(cx, TaggedProto(proto));
+ bool isCachable = NewObjectWithTaggedProtoIsCachable(cx, taggedProto, newKind,
+ &ArrayObject::class_);
+ if (isCachable) {
+ NewObjectCache& cache = cx->caches().newObjectCache;
+ NewObjectCache::EntryIndex entry = -1;
+ if (cache.lookupProto(&ArrayObject::class_, proto, allocKind, &entry)) {
+ gc::InitialHeap heap = GetInitialHeap(newKind, &ArrayObject::class_);
+ AutoSetNewObjectMetadata metadata(cx);
+ JSObject* obj = cache.newObjectFromHit(cx, entry, heap);
+ if (obj) {
+ /* Fixup the elements pointer and length, which may be incorrect. */
+ ArrayObject* arr = &obj->as<ArrayObject>();
+ arr->setFixedElements();
+ arr->setLength(length);
+ if (maxLength > 0 &&
+ !EnsureNewArrayElements(cx, arr, std::min(maxLength, length))) {
+ return nullptr;
+ }
+ return arr;
+ }
+ }
+ }
+
+ RootedObjectGroup group(cx,
+ ObjectGroup::defaultNewGroup(cx, &ArrayObject::class_,
+ TaggedProto(proto)));
+ if (!group) {
+ return nullptr;
+ }
+
+ /*
+ * Get a shape with zero fixed slots, regardless of the size class.
+ * See JSObject::createArray.
+ */
+ RootedShape shape(cx, EmptyShape::getInitialShape(cx, &ArrayObject::class_,
+ TaggedProto(proto),
+ gc::AllocKind::OBJECT0));
+ if (!shape) {
+ return nullptr;
+ }
+
+ AutoSetNewObjectMetadata metadata(cx);
+ RootedArrayObject arr(cx, ArrayObject::createArray(
+ cx, allocKind, GetInitialHeap(newKind, group),
+ shape, group, length, metadata));
+ if (!arr) {
+ return nullptr;
+ }
+
+ if (shape->isEmptyShape()) {
+ if (!AddLengthProperty(cx, arr)) {
+ return nullptr;
+ }
+ shape = arr->lastProperty();
+ EmptyShape::insertInitialShape(cx, shape, proto);
+ }
+
+ if (isCachable) {
+ NewObjectCache& cache = cx->caches().newObjectCache;
+ NewObjectCache::EntryIndex entry = -1;
+ cache.lookupProto(&ArrayObject::class_, proto, allocKind, &entry);
+ cache.fillProto(entry, &ArrayObject::class_, taggedProto, allocKind, arr);
+ }
+
+ if (maxLength > 0 &&
+ !EnsureNewArrayElements(cx, arr, std::min(maxLength, length))) {
+ return nullptr;
+ }
+
+ probes::CreateObject(cx, arr);
+ return arr;
+}
+
+ArrayObject* JS_FASTCALL
+js::NewDenseEmptyArray(JSContext* cx, HandleObject proto /* = nullptr */) {
+ return NewArray<0>(cx, 0, proto, GenericObject);
+}
+
+ArrayObject* JS_FASTCALL js::NewTenuredDenseEmptyArray(
+ JSContext* cx, HandleObject proto /* = nullptr */) {
+ return NewArray<0>(cx, 0, proto, TenuredObject);
+}
+
+ArrayObject* JS_FASTCALL js::NewDenseFullyAllocatedArray(
+ JSContext* cx, uint32_t length, HandleObject proto /* = nullptr */,
+ NewObjectKind newKind /* = GenericObject */) {
+ return NewArray<UINT32_MAX>(cx, length, proto, newKind);
+}
+
+ArrayObject* js::NewDensePartlyAllocatedArray(
+ JSContext* cx, uint32_t length, HandleObject proto /* = nullptr */,
+ NewObjectKind newKind /* = GenericObject */) {
+ return NewArray<ArrayObject::EagerAllocationMaxLength>(cx, length, proto,
+ newKind);
+}
+
+ArrayObject* JS_FASTCALL js::NewDenseUnallocatedArray(
+ JSContext* cx, uint32_t length, HandleObject proto /* = nullptr */,
+ NewObjectKind newKind /* = GenericObject */) {
+ return NewArray<0>(cx, length, proto, newKind);
+}
+
+// values must point at already-rooted Value objects
+ArrayObject* js::NewDenseCopiedArray(
+ JSContext* cx, uint32_t length, const Value* values,
+ HandleObject proto /* = nullptr */,
+ NewObjectKind newKind /* = GenericObject */) {
+ ArrayObject* arr = NewArray<UINT32_MAX>(cx, length, proto, newKind);
+ if (!arr) {
+ return nullptr;
+ }
+
+ MOZ_ASSERT(arr->getDenseCapacity() >= length);
+ MOZ_ASSERT(arr->getDenseInitializedLength() == 0);
+
+ if (values) {
+ arr->initDenseElements(values, length);
+ }
+
+ return arr;
+}
+
+ArrayObject* js::NewDenseFullyAllocatedArrayWithTemplate(
+ JSContext* cx, uint32_t length, ArrayObject* templateObject) {
+ AutoSetNewObjectMetadata metadata(cx);
+ gc::AllocKind allocKind = GuessArrayGCKind(length);
+ MOZ_ASSERT(CanChangeToBackgroundAllocKind(allocKind, &ArrayObject::class_));
+ allocKind = ForegroundToBackgroundAllocKind(allocKind);
+
+ RootedObjectGroup group(cx, templateObject->group());
+ RootedShape shape(cx, templateObject->lastProperty());
+
+ gc::InitialHeap heap = GetInitialHeap(GenericObject, group);
+ Rooted<ArrayObject*> arr(
+ cx, ArrayObject::createArray(cx, allocKind, heap, shape, group, length,
+ metadata));
+ if (!arr) {
+ return nullptr;
+ }
+
+ if (!EnsureNewArrayElements(cx, arr, length)) {
+ return nullptr;
+ }
+
+ probes::CreateObject(cx, arr);
+
+ return arr;
+}
+
+// TODO(no-TI): clean up.
+ArrayObject* js::NewArrayWithGroup(JSContext* cx, uint32_t length,
+ HandleObjectGroup group) {
+ // Ion can call this with a group from a different realm when calling
+ // another realm's Array constructor.
+ Maybe<AutoRealm> ar;
+ if (cx->realm() != group->realm()) {
+ MOZ_ASSERT(cx->compartment() == group->compartment());
+ ar.emplace(cx, group);
+ }
+
+ return NewDenseFullyAllocatedArray(cx, length);
+}
+
+#ifdef DEBUG
+bool js::ArrayInfo(JSContext* cx, unsigned argc, Value* vp) {
+ CallArgs args = CallArgsFromVp(argc, vp);
+ RootedObject obj(cx);
+
+ for (unsigned i = 0; i < args.length(); i++) {
+ HandleValue arg = args[i];
+
+ UniqueChars bytes =
+ DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, arg, nullptr);
+ if (!bytes) {
+ return false;
+ }
+ if (arg.isPrimitive() || !(obj = arg.toObjectOrNull())->is<ArrayObject>()) {
+ fprintf(stderr, "%s: not array\n", bytes.get());
+ continue;
+ }
+ fprintf(stderr, "%s: (len %u", bytes.get(),
+ obj->as<ArrayObject>().length());
+ fprintf(stderr, ", capacity %u", obj->as<ArrayObject>().getDenseCapacity());
+ fputs(")\n", stderr);
+ }
+
+ args.rval().setUndefined();
+ return true;
+}
+#endif
+
+void js::ArraySpeciesLookup::initialize(JSContext* cx) {
+ MOZ_ASSERT(state_ == State::Uninitialized);
+
+ // Get the canonical Array.prototype.
+ NativeObject* arrayProto = cx->global()->maybeGetArrayPrototype();
+
+ // Leave the cache uninitialized if the Array class itself is not yet
+ // initialized.
+ if (!arrayProto) {
+ return;
+ }
+
+ // Get the canonical Array constructor.
+ const Value& arrayCtorValue = cx->global()->getConstructor(JSProto_Array);
+ MOZ_ASSERT(arrayCtorValue.isObject(),
+ "The Array constructor is initialized iff Array.prototype is "
+ "initialized");
+ JSFunction* arrayCtor = &arrayCtorValue.toObject().as<JSFunction>();
+
+ // Shortcut returns below means Array[@@species] will never be
+ // optimizable, set to disabled now, and clear it later when we succeed.
+ state_ = State::Disabled;
+
+ // Look up Array.prototype[@@iterator] and ensure it's a data property.
+ Shape* ctorShape = arrayProto->lookup(cx, NameToId(cx->names().constructor));
+ if (!ctorShape || !ctorShape->isDataProperty()) {
+ return;
+ }
+
+ // Get the referred value, and ensure it holds the canonical Array
+ // constructor.
+ JSFunction* ctorFun;
+ if (!IsFunctionObject(arrayProto->getSlot(ctorShape->slot()), &ctorFun)) {
+ return;
+ }
+ if (ctorFun != arrayCtor) {
+ return;
+ }
+
+ // Look up the '@@species' value on Array
+ Shape* speciesShape =
+ arrayCtor->lookup(cx, SYMBOL_TO_JSID(cx->wellKnownSymbols().species));
+ if (!speciesShape || !speciesShape->hasGetterValue()) {
+ return;
+ }
+
+ // Get the referred value, ensure it holds the canonical Array[@@species]
+ // function.
+ JSFunction* speciesFun;
+ if (!IsFunctionObject(speciesShape->getterValue(), &speciesFun)) {
+ return;
+ }
+ if (!IsSelfHostedFunctionWithName(speciesFun, cx->names().ArraySpecies)) {
+ return;
+ }
+
+ // Store raw pointers below. This is okay to do here, because all objects
+ // are in the tenured heap.
+ MOZ_ASSERT(!IsInsideNursery(arrayProto));
+ MOZ_ASSERT(!IsInsideNursery(arrayCtor));
+ MOZ_ASSERT(!IsInsideNursery(arrayCtor->lastProperty()));
+ MOZ_ASSERT(!IsInsideNursery(speciesShape));
+ MOZ_ASSERT(!IsInsideNursery(speciesFun));
+ MOZ_ASSERT(!IsInsideNursery(arrayProto->lastProperty()));
+
+ state_ = State::Initialized;
+ arrayProto_ = arrayProto;
+ arrayConstructor_ = arrayCtor;
+ arrayConstructorShape_ = arrayCtor->lastProperty();
+#ifdef DEBUG
+ arraySpeciesShape_ = speciesShape;
+ canonicalSpeciesFunc_ = speciesFun;
+#endif
+ arrayProtoShape_ = arrayProto->lastProperty();
+ arrayProtoConstructorSlot_ = ctorShape->slot();
+}
+
+void js::ArraySpeciesLookup::reset() {
+ AlwaysPoison(this, JS_RESET_VALUE_PATTERN, sizeof(*this),
+ MemCheckKind::MakeUndefined);
+ state_ = State::Uninitialized;
+}
+
+bool js::ArraySpeciesLookup::isArrayStateStillSane() {
+ MOZ_ASSERT(state_ == State::Initialized);
+
+ // Ensure that Array.prototype still has the expected shape.
+ if (arrayProto_->lastProperty() != arrayProtoShape_) {
+ return false;
+ }
+
+ // Ensure that Array.prototype.constructor contains the canonical Array
+ // constructor function.
+ if (arrayProto_->getSlot(arrayProtoConstructorSlot_) !=
+ ObjectValue(*arrayConstructor_)) {
+ return false;
+ }
+
+ // Ensure that Array still has the expected shape.
+ if (arrayConstructor_->lastProperty() != arrayConstructorShape_) {
+ return false;
+ }
+
+ // Ensure the species getter contains the canonical @@species function.
+ // Note: This is currently guaranteed to be always true, because modifying
+ // the getter property implies a new shape is generated. If this ever
+ // changes, convert this assertion into an if-statement.
+ MOZ_ASSERT(arraySpeciesShape_->getterObject() == canonicalSpeciesFunc_);
+
+ return true;
+}
+
+bool js::ArraySpeciesLookup::tryOptimizeArray(JSContext* cx,
+ ArrayObject* array) {
+ if (state_ == State::Uninitialized) {
+ // If the cache is not initialized, initialize it.
+ initialize(cx);
+ } else if (state_ == State::Initialized && !isArrayStateStillSane()) {
+ // Otherwise, if the array state is no longer sane, reinitialize.
+ reset();
+ initialize(cx);
+ }
+
+ // If the cache is disabled or still uninitialized, don't bother trying to
+ // optimize.
+ if (state_ != State::Initialized) {
+ return false;
+ }
+
+ // By the time we get here, we should have a sane array state.
+ MOZ_ASSERT(isArrayStateStillSane());
+
+ // Ensure |array|'s prototype is the actual Array.prototype.
+ if (array->staticPrototype() != arrayProto_) {
+ return false;
+ }
+
+ // Ensure |array| doesn't define any own properties besides its
+ // non-deletable "length" property. This serves as a quick check to make
+ // sure |array| doesn't define an own "constructor" property which may
+ // shadow Array.prototype.constructor.
+ Shape* shape = array->shape();
+ if (shape->previous() && !shape->previous()->isEmptyShape()) {
+ return false;
+ }
+
+ MOZ_ASSERT(JSID_IS_ATOM(shape->propidRaw(), cx->names().length));
+ return true;
+}
+
+JS_PUBLIC_API JSObject* JS::NewArrayObject(JSContext* cx,
+ const HandleValueArray& contents) {
+ MOZ_ASSERT(!cx->zone()->isAtomsZone());
+ AssertHeapIsIdle();
+ CHECK_THREAD(cx);
+ cx->check(contents);
+
+ return NewDenseCopiedArray(cx, contents.length(), contents.begin());
+}
+
+JS_PUBLIC_API JSObject* JS::NewArrayObject(JSContext* cx, size_t length) {
+ MOZ_ASSERT(!cx->zone()->isAtomsZone());
+ AssertHeapIsIdle();
+ CHECK_THREAD(cx);
+
+ return NewDenseFullyAllocatedArray(cx, length);
+}
+
+JS_PUBLIC_API bool JS::IsArrayObject(JSContext* cx, Handle<JSObject*> obj,
+ bool* isArray) {
+ return IsGivenTypeObject(cx, obj, ESClass::Array, isArray);
+}
+
+JS_PUBLIC_API bool JS::IsArrayObject(JSContext* cx, Handle<Value> value,
+ bool* isArray) {
+ if (!value.isObject()) {
+ *isArray = false;
+ return true;
+ }
+
+ Rooted<JSObject*> obj(cx, &value.toObject());
+ return IsArrayObject(cx, obj, isArray);
+}
+
+JS_PUBLIC_API bool JS::GetArrayLength(JSContext* cx, Handle<JSObject*> obj,
+ uint32_t* lengthp) {
+ AssertHeapIsIdle();
+ CHECK_THREAD(cx);
+ cx->check(obj);
+
+ return GetLengthProperty(cx, obj, lengthp);
+}
+
+JS_PUBLIC_API bool JS::SetArrayLength(JSContext* cx, Handle<JSObject*> obj,
+ uint32_t length) {
+ AssertHeapIsIdle();
+ CHECK_THREAD(cx);
+ cx->check(obj);
+
+ return SetLengthProperty(cx, obj, length);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-19 04:02:08 +0000