/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * vim: set sw=4 ts=8 et tw=78: * * 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/. */ /* * JS array class. * * Array objects begin as "dense" arrays, optimized for index-only property * access over a vector of slots with high load factor. Array methods * optimize for denseness by testing that the object's class is * &ArrayClass, and can then directly manipulate the slots for efficiency. * * We track these pieces of metadata for arrays in dense mode: * - The array's length property as a uint32, accessible with * getArrayLength(), setArrayLength(). * - The number of element slots (capacity), gettable with * getDenseArrayCapacity(). * - The array's initialized length, accessible with * getDenseArrayInitializedLength(). * * In dense mode, holes in the array are represented by * MagicValue(JS_ARRAY_HOLE) invalid values. * * NB: the capacity and length of a dense array are entirely unrelated! The * length may be greater than, less than, or equal to the capacity. The first * case may occur when the user writes "new Array(100)", in which case the * length is 100 while the capacity remains 0 (indices below length and above * capacity must be treated as holes). See array_length_setter for another * explanation of how the first case may occur. * * The initialized length of a dense array specifies the number of elements * that have been initialized. All elements above the initialized length are * holes in the array, and the memory for all elements between the initialized * length and capacity is left uninitialized. When type inference is disabled, * the initialized length always equals the array's capacity. When inference is * enabled, the initialized length is some value less than or equal to both the * array's length and the array's capacity. * * With inference enabled, there is flexibility in exactly the value the * initialized length must hold, e.g. if an array has length 5, capacity 10, * completely empty, it is valid for the initialized length to be any value * between zero and 5, as long as the in memory values below the initialized * length have been initialized with a hole value. However, in such cases we * want to keep the initialized length as small as possible: if the array is * known to have no hole values below its initialized length, then it is a * "packed" array and can be accessed much faster by JIT code. * * Arrays are converted to use SlowArrayClass when any of these conditions * are met: * - there are more than MIN_SPARSE_INDEX slots total and the load factor * (COUNT / capacity) is less than 0.25 * - a property is set that is not indexed (and not "length") * - a property is defined that has non-default property attributes. * * Dense arrays do not track property creation order, so unlike other native * objects and slow arrays, enumerating an array does not necessarily visit the * properties in the order they were created. We could instead maintain the * scope to track property enumeration order, but still use the fast slot * access. That would have the same memory cost as just using a * SlowArrayClass, but have the same performance characteristics as a dense * array for slot accesses, at some cost in code complexity. */ #include "mozilla/FloatingPoint.h" #include "mozilla/RangedPtr.h" #include #include #include #include "jstypes.h" #include "jsutil.h" #include "jsapi.h" #include "jsarray.h" #include "jsatom.h" #include "jsbool.h" #include "jscntxt.h" #include "jsversion.h" #include "jsfun.h" #include "jsgc.h" #include "jsinterp.h" #include "jsiter.h" #include "jslock.h" #include "jsnum.h" #include "jsobj.h" #include "jsscope.h" #include "jswrapper.h" #include "methodjit/MethodJIT.h" #include "methodjit/StubCalls.h" #include "methodjit/StubCalls-inl.h" #include "gc/Marking.h" #include "vm/ArgumentsObject.h" #include "vm/NumericConversions.h" #include "vm/StringBuffer.h" #include "ds/Sort.h" #include "jsarrayinlines.h" #include "jsatominlines.h" #include "jscntxtinlines.h" #include "jsobjinlines.h" #include "jsscopeinlines.h" #include "jsstrinlines.h" #include "vm/ArgumentsObject-inl.h" #include "vm/ObjectImpl-inl.h" #include "vm/Stack-inl.h" using namespace mozilla; using namespace js; using namespace js::gc; using namespace js::types; namespace js { JSBool GetLengthProperty(JSContext *cx, HandleObject obj, uint32_t *lengthp) { if (obj->isArray()) { *lengthp = obj->getArrayLength(); return true; } if (obj->isArguments()) { ArgumentsObject &argsobj = obj->asArguments(); if (!argsobj.hasOverriddenLength()) { *lengthp = argsobj.initialLength(); return true; } } RootedValue value(cx); if (!JSObject::getProperty(cx, obj, obj, cx->names().length, &value)) return false; if (value.isInt32()) { *lengthp = uint32_t(value.toInt32()); /* uint32_t cast does ToUint32_t */ return true; } return ToUint32(cx, value, (uint32_t *)lengthp); } /* * Determine if the id represents an array index or an XML property 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 JSVAL_IS_INT(id) * 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. * */ JS_FRIEND_API(bool) StringIsArrayIndex(JSLinearString *str, uint32_t *indexp) { const jschar *s = str->chars(); uint32_t length = str->length(); const jschar *end = s + length; if (length == 0 || length > (sizeof("4294967294") - 1) || !JS7_ISDEC(*s)) return false; uint32_t c = 0, previous = 0; uint32_t index = JS7_UNDEC(*s++); /* Don't allow leading zeros. */ if (index == 0 && s != end) return false; for (; s < end; s++) { if (!JS7_ISDEC(*s)) return false; previous = index; c = JS7_UNDEC(*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))) { JS_ASSERT(index <= MAX_ARRAY_INDEX); *indexp = index; return true; } return false; } } bool JSObject::willBeSparseDenseArray(unsigned requiredCapacity, unsigned newElementsHint) { JS_ASSERT(isDenseArray()); JS_ASSERT(requiredCapacity > MIN_SPARSE_INDEX); unsigned cap = getDenseArrayCapacity(); JS_ASSERT(requiredCapacity >= cap); if (requiredCapacity >= JSObject::NELEMENTS_LIMIT) return true; unsigned minimalDenseCount = requiredCapacity / 4; if (newElementsHint >= minimalDenseCount) return false; minimalDenseCount -= newElementsHint; if (minimalDenseCount > cap) return true; unsigned len = getDenseArrayInitializedLength(); const Value *elems = getDenseArrayElements(); for (unsigned i = 0; i < len; i++) { if (!elems[i].isMagic(JS_ARRAY_HOLE) && !--minimalDenseCount) return false; } return true; } bool JSObject::arrayGetOwnDataElement(JSContext *cx, size_t i, Value *vp) { JS_ASSERT(isArray()); if (isDenseArray()) { if (i >= getArrayLength()) vp->setMagic(JS_ARRAY_HOLE); else *vp = getDenseArrayElement(uint32_t(i)); return true; } jsid id; if (!IndexToId(cx, i, &id)) return false; Shape *shape = nativeLookup(cx, id); if (!shape || !shape->isDataDescriptor()) vp->setMagic(JS_ARRAY_HOLE); else *vp = getSlot(shape->slot()); return true; } bool DoubleIndexToId(JSContext *cx, double index, jsid *id) { if (index == uint32_t(index)) return IndexToId(cx, uint32_t(index), id); return ValueToId(cx, DoubleValue(index), id); } /* * If the property at the given index exists, get its value into location * pointed by vp and set *hole to false. Otherwise set *hole to true and *vp * to JSVAL_VOID. This function assumes that the location pointed by vp is * properly rooted and can be used as GC-protected storage for temporaries. */ static inline bool DoGetElement(JSContext *cx, HandleObject obj, double index, JSBool *hole, MutableHandleValue vp) { RootedId id(cx); if (!DoubleIndexToId(cx, index, id.address())) return false; RootedObject obj2(cx); RootedShape prop(cx); if (!JSObject::lookupGeneric(cx, obj, id, &obj2, &prop)) return false; if (!prop) { vp.setUndefined(); *hole = true; } else { if (!JSObject::getGeneric(cx, obj, obj, id, vp)) return false; *hole = false; } return true; } static inline bool DoGetElement(JSContext *cx, HandleObject obj, uint32_t index, JSBool *hole, MutableHandleValue vp) { bool present; if (!JSObject::getElementIfPresent(cx, obj, obj, index, vp, &present)) return false; *hole = !present; if (*hole) vp.setUndefined(); return true; } template static void AssertGreaterThanZero(IndexType index) { JS_ASSERT(index >= 0); JS_ASSERT(index == floor(index)); } template<> void AssertGreaterThanZero(uint32_t index) { } template static JSBool GetElement(JSContext *cx, HandleObject obj, IndexType index, JSBool *hole, MutableHandleValue vp) { AssertGreaterThanZero(index); if (obj->isDenseArray() && index < obj->getDenseArrayInitializedLength()) { vp.set(obj->getDenseArrayElement(uint32_t(index))); if (!vp.isMagic(JS_ARRAY_HOLE)) { *hole = JS_FALSE; return JS_TRUE; } } if (obj->isArguments()) { if (obj->asArguments().maybeGetElement(uint32_t(index), vp)) { *hole = JS_FALSE; return true; } } return DoGetElement(cx, obj, index, hole, vp); } namespace js { static bool GetElementsSlow(JSContext *cx, HandleObject aobj, uint32_t length, Value *vp) { for (uint32_t i = 0; i < length; i++) { if (!JSObject::getElement(cx, aobj, aobj, i, MutableHandleValue::fromMarkedLocation(&vp[i]))) return false; } return true; } bool GetElements(JSContext *cx, HandleObject aobj, uint32_t length, Value *vp) { if (aobj->isDenseArray() && length <= aobj->getDenseArrayInitializedLength() && !js_PrototypeHasIndexedProperties(aobj)) { /* The prototype does not have indexed properties so hole = undefined */ const Value *srcbeg = aobj->getDenseArrayElements(); const Value *srcend = srcbeg + length; const Value *src = srcbeg; for (Value *dst = vp; src < srcend; ++dst, ++src) *dst = src->isMagic(JS_ARRAY_HOLE) ? UndefinedValue() : *src; return true; } if (aobj->isArguments()) { ArgumentsObject &argsobj = aobj->asArguments(); if (!argsobj.hasOverriddenLength()) { if (argsobj.maybeGetElements(0, length, vp)) return true; } } return GetElementsSlow(cx, aobj, length, vp); } } /* * Set the value of the property at the given index to v assuming v is rooted. */ static JSBool SetArrayElement(JSContext *cx, HandleObject obj, double index, HandleValue v) { JS_ASSERT(index >= 0); if (obj->isDenseArray()) { /* Predicted/prefetched code should favor the remains-dense case. */ JSObject::EnsureDenseResult result = JSObject::ED_SPARSE; do { if (index > uint32_t(-1)) break; uint32_t idx = uint32_t(index); result = obj->ensureDenseArrayElements(cx, idx, 1); if (result != JSObject::ED_OK) break; if (idx >= obj->getArrayLength()) obj->setDenseArrayLength(idx + 1); JSObject::setDenseArrayElementWithType(cx, obj, idx, v); return true; } while (false); if (result == JSObject::ED_FAILED) return false; JS_ASSERT(result == JSObject::ED_SPARSE); if (!JSObject::makeDenseArraySlow(cx, obj)) return JS_FALSE; } RootedId id(cx); if (!DoubleIndexToId(cx, index, id.address())) return false; RootedValue tmp(cx, v); return JSObject::setGeneric(cx, obj, obj, id, &tmp, true); } /* * Delete the element |index| from |obj|. If |strict|, do a strict * deletion: throw if the property is not configurable. * * - Return 1 if the deletion succeeds (that is, ES5's [[Delete]] would * return true) * * - Return 0 if the deletion fails because the property is not * configurable (that is, [[Delete]] would return false). Note that if * |strict| is true we will throw, not return zero. * * - Return -1 if an exception occurs (that is, [[Delete]] would throw). */ static int DeleteArrayElement(JSContext *cx, HandleObject obj, double index, bool strict) { JS_ASSERT(index >= 0); JS_ASSERT(floor(index) == index); if (obj->isDenseArray()) { if (index <= UINT32_MAX) { uint32_t idx = uint32_t(index); if (idx < obj->getDenseArrayInitializedLength()) { obj->markDenseArrayNotPacked(cx); obj->setDenseArrayElement(idx, MagicValue(JS_ARRAY_HOLE)); if (!js_SuppressDeletedElement(cx, obj, idx)) return -1; } } return 1; } RootedValue v(cx); if (index <= UINT32_MAX) { if (!JSObject::deleteElement(cx, obj, uint32_t(index), &v, strict)) return -1; } else { if (!JSObject::deleteByValue(cx, obj, DoubleValue(index), &v, strict)) return -1; } return v.isTrue() ? 1 : 0; } /* * When hole is true, delete the property at the given index. Otherwise set * its value to v assuming v is rooted. */ static JSBool SetOrDeleteArrayElement(JSContext *cx, HandleObject obj, double index, JSBool hole, HandleValue v) { if (hole) { JS_ASSERT(v.isUndefined()); return DeleteArrayElement(cx, obj, index, true) >= 0; } return SetArrayElement(cx, obj, index, v); } JSBool js::SetLengthProperty(JSContext *cx, HandleObject obj, double length) { RootedValue v(cx, NumberValue(length)); /* We don't support read-only array length yet. */ return JSObject::setProperty(cx, obj, obj, cx->names().length, &v, false); } /* * Since SpiderMonkey supports cross-class prototype-based delegation, we have * to be careful about the length getter and setter being called on an object * not of Array class. For the getter, we search obj's prototype chain for the * array that caused this getter to be invoked. In the setter case to overcome * the JSPROP_SHARED attribute, we must define a shadowing length property. */ static JSBool array_length_getter(JSContext *cx, HandleObject obj_, HandleId id, MutableHandleValue vp) { RootedObject obj(cx, obj_); do { if (obj->isArray()) { vp.setNumber(obj->getArrayLength()); return true; } if (!JSObject::getProto(cx, obj, &obj)) return false; } while (obj); return true; } static JSBool array_length_setter(JSContext *cx, HandleObject obj, HandleId id, JSBool strict, MutableHandleValue vp) { if (!obj->isArray()) { return JSObject::defineProperty(cx, obj, cx->names().length, vp, NULL, NULL, JSPROP_ENUMERATE); } uint32_t newlen; if (!ToUint32(cx, vp, &newlen)) return false; double d; if (!ToNumber(cx, vp, &d)) return false; if (d != newlen) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_BAD_ARRAY_LENGTH); return false; } uint32_t oldlen = obj->getArrayLength(); if (oldlen == newlen) return true; vp.setNumber(newlen); if (oldlen < newlen) { JSObject::setArrayLength(cx, obj, newlen); return true; } if (obj->isDenseArray()) { /* * Don't reallocate if we're not actually shrinking our slots. If we do * shrink slots here, shrink the initialized length too. This permits us * us to disregard length when reading from arrays as long we are within * the initialized capacity. */ uint32_t oldcap = obj->getDenseArrayCapacity(); uint32_t oldinit = obj->getDenseArrayInitializedLength(); if (oldinit > newlen) obj->setDenseArrayInitializedLength(newlen); if (oldcap > newlen) obj->shrinkElements(cx, newlen); } else if (oldlen - newlen < (1 << 24)) { do { --oldlen; if (!JS_CHECK_OPERATION_LIMIT(cx)) { JSObject::setArrayLength(cx, obj, oldlen + 1); return false; } int deletion = DeleteArrayElement(cx, obj, oldlen, strict); if (deletion <= 0) { JSObject::setArrayLength(cx, obj, oldlen + 1); return deletion >= 0; } } while (oldlen != newlen); } else { /* * We are going to remove a lot of indexes in a presumably sparse * array. So instead of looping through indexes between newlen and * oldlen, we iterate through all properties and remove those that * correspond to indexes in the half-open range [newlen, oldlen). See * bug 322135. */ RootedObject iter(cx, JS_NewPropertyIterator(cx, obj)); if (!iter) return false; uint32_t gap = oldlen - newlen; for (;;) { jsid nid; if (!JS_CHECK_OPERATION_LIMIT(cx) || !JS_NextProperty(cx, iter, &nid)) return false; if (JSID_IS_VOID(nid)) break; uint32_t index; RootedValue junk(cx); if (js_IdIsIndex(nid, &index) && index - newlen < gap && !JSObject::deleteElement(cx, obj, index, &junk, false)) { return false; } } } JSObject::setArrayLength(cx, obj, newlen); return true; } /* Returns true if the dense array has an own property at the index. */ static inline bool IsDenseArrayIndex(JSObject *obj, uint32_t index) { JS_ASSERT(obj->isDenseArray()); return index < obj->getDenseArrayInitializedLength() && !obj->getDenseArrayElement(index).isMagic(JS_ARRAY_HOLE); } /* * We have only indexed properties up to initialized length, plus the * length property. For all else, we delegate to the prototype. */ static inline bool IsDenseArrayId(JSContext *cx, JSObject *obj, jsid id) { JS_ASSERT(obj->isDenseArray()); uint32_t i; return JSID_IS_ATOM(id, cx->names().length) || (js_IdIsIndex(id, &i) && IsDenseArrayIndex(obj, i)); } static JSBool array_lookupGeneric(JSContext *cx, HandleObject obj, HandleId id, MutableHandleObject objp, MutableHandleShape propp) { if (!obj->isDenseArray()) return baseops::LookupProperty(cx, obj, id, objp, propp); if (IsDenseArrayId(cx, obj, id)) { MarkNonNativePropertyFound(obj, propp); objp.set(obj); return JS_TRUE; } RootedObject proto(cx, obj->getProto()); if (!proto) { objp.set(NULL); propp.set(NULL); return JS_TRUE; } return JSObject::lookupGeneric(cx, proto, id, objp, propp); } static JSBool array_lookupProperty(JSContext *cx, HandleObject obj, HandlePropertyName name, MutableHandleObject objp, MutableHandleShape propp) { Rooted id(cx, NameToId(name)); return array_lookupGeneric(cx, obj, id, objp, propp); } static JSBool array_lookupElement(JSContext *cx, HandleObject obj, uint32_t index, MutableHandleObject objp, MutableHandleShape propp) { if (!obj->isDenseArray()) return baseops::LookupElement(cx, obj, index, objp, propp); if (IsDenseArrayIndex(obj, index)) { MarkNonNativePropertyFound(obj, propp); objp.set(obj); return true; } RootedObject proto(cx, obj->getProto()); if (proto) return JSObject::lookupElement(cx, proto, index, objp, propp); objp.set(NULL); propp.set(NULL); return true; } static JSBool array_lookupSpecial(JSContext *cx, HandleObject obj, HandleSpecialId sid, MutableHandleObject objp, MutableHandleShape propp) { Rooted id(cx, SPECIALID_TO_JSID(sid)); return array_lookupGeneric(cx, obj, id, objp, propp); } JSBool js_GetDenseArrayElementValue(JSContext *cx, HandleObject obj, jsid id, Value *vp) { JS_ASSERT(obj->isDenseArray()); uint32_t i; if (!js_IdIsIndex(id, &i)) { JS_ASSERT(JSID_IS_ATOM(id, cx->names().length)); vp->setNumber(obj->getArrayLength()); return JS_TRUE; } *vp = obj->getDenseArrayElement(i); return JS_TRUE; } static JSBool array_getProperty(JSContext *cx, HandleObject obj, HandleObject receiver, HandlePropertyName name, MutableHandleValue vp) { if (name == cx->names().length) { vp.setNumber(obj->getArrayLength()); return true; } if (!obj->isDenseArray()) { Rooted id(cx, NameToId(name)); return baseops::GetProperty(cx, obj, receiver, id, vp); } RootedObject proto(cx, obj->getProto()); if (!proto) { vp.setUndefined(); return true; } return JSObject::getProperty(cx, proto, receiver, name, vp); } static JSBool array_getElement(JSContext *cx, HandleObject obj, HandleObject receiver, uint32_t index, MutableHandleValue vp) { if (!obj->isDenseArray()) return baseops::GetElement(cx, obj, receiver, index, vp); if (index < obj->getDenseArrayInitializedLength()) { vp.set(obj->getDenseArrayElement(index)); if (!vp.isMagic(JS_ARRAY_HOLE)) { /* Type information for dense array elements must be correct. */ JS_ASSERT_IF(!obj->hasSingletonType(), js::types::TypeHasProperty(cx, obj->type(), JSID_VOID, vp)); return true; } } RootedObject proto(cx, obj->getProto()); if (!proto) { vp.setUndefined(); return true; } return JSObject::getElement(cx, proto, receiver, index, vp); } static JSBool array_getSpecial(JSContext *cx, HandleObject obj, HandleObject receiver, HandleSpecialId sid, MutableHandleValue vp) { if (obj->isDenseArray() && !obj->getProto()) { vp.setUndefined(); return true; } Rooted id(cx, SPECIALID_TO_JSID(sid)); return baseops::GetProperty(cx, obj, receiver, id, vp); } static JSBool array_getGeneric(JSContext *cx, HandleObject obj, HandleObject receiver, HandleId id, MutableHandleValue vp) { RootedValue idval(cx, IdToValue(id)); uint32_t index; if (IsDefinitelyIndex(idval, &index)) return array_getElement(cx, obj, receiver, index, vp); Rooted sid(cx); if (ValueIsSpecial(obj, &idval, sid.address(), cx)) return array_getSpecial(cx, obj, receiver, sid, vp); JSAtom *atom = ToAtom(cx, idval); if (!atom) return false; if (atom->isIndex(&index)) return array_getElement(cx, obj, receiver, index, vp); Rooted name(cx, atom->asPropertyName()); return array_getProperty(cx, obj, receiver, name, vp); } static JSBool slowarray_addProperty(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp) { uint32_t index, length; if (!js_IdIsIndex(id, &index)) return JS_TRUE; length = obj->getArrayLength(); if (index >= length) JSObject::setArrayLength(cx, obj, index + 1); return JS_TRUE; } static JSBool array_setGeneric(JSContext *cx, HandleObject obj, HandleId id, MutableHandleValue vp, JSBool strict) { if (JSID_IS_ATOM(id, cx->names().length)) return array_length_setter(cx, obj, id, strict, vp); if (!obj->isDenseArray()) return baseops::SetPropertyHelper(cx, obj, obj, id, 0, vp, strict); do { uint32_t i; if (!js_IdIsIndex(id, &i)) break; if (js_PrototypeHasIndexedProperties(obj)) break; JSObject::EnsureDenseResult result = obj->ensureDenseArrayElements(cx, i, 1); if (result != JSObject::ED_OK) { if (result == JSObject::ED_FAILED) return false; JS_ASSERT(result == JSObject::ED_SPARSE); break; } if (i >= obj->getArrayLength()) obj->setDenseArrayLength(i + 1); JSObject::setDenseArrayElementWithType(cx, obj, i, vp); return true; } while (false); if (!JSObject::makeDenseArraySlow(cx, obj)) return false; return baseops::SetPropertyHelper(cx, obj, obj, id, 0, vp, strict); } static JSBool array_setProperty(JSContext *cx, HandleObject obj, HandlePropertyName name, MutableHandleValue vp, JSBool strict) { Rooted id(cx, NameToId(name)); return array_setGeneric(cx, obj, id, vp, strict); } static JSBool array_setElement(JSContext *cx, HandleObject obj, uint32_t index, MutableHandleValue vp, JSBool strict) { RootedId id(cx); if (!IndexToId(cx, index, id.address())) return false; if (!obj->isDenseArray()) return baseops::SetPropertyHelper(cx, obj, obj, id, 0, vp, strict); do { /* * UINT32_MAX is not an array index and must not affect the length * property, so specifically reject it. */ if (index == UINT32_MAX) break; if (js_PrototypeHasIndexedProperties(obj)) break; JSObject::EnsureDenseResult result = obj->ensureDenseArrayElements(cx, index, 1); if (result != JSObject::ED_OK) { if (result == JSObject::ED_FAILED) return false; JS_ASSERT(result == JSObject::ED_SPARSE); break; } if (index >= obj->getArrayLength()) obj->setDenseArrayLength(index + 1); JSObject::setDenseArrayElementWithType(cx, obj, index, vp); return true; } while (false); if (!JSObject::makeDenseArraySlow(cx, obj)) return false; return baseops::SetPropertyHelper(cx, obj, obj, id, 0, vp, strict); } static JSBool array_setSpecial(JSContext *cx, HandleObject obj, HandleSpecialId sid, MutableHandleValue vp, JSBool strict) { Rooted id(cx, SPECIALID_TO_JSID(sid)); return array_setGeneric(cx, obj, id, vp, strict); } JSBool js_PrototypeHasIndexedProperties(JSObject *obj) { JS_ASSERT(obj->isDenseArray()); /* * Walk up the prototype chain and see if this indexed element already * exists. If we hit the end of the prototype chain, it's safe to set the * element on the original object. */ while ((obj = obj->getProto()) != NULL) { /* * If the prototype is a non-native object (possibly a dense array), or * a native object (possibly a slow array) that has indexed properties, * return true. */ if (!obj->isNative()) return JS_TRUE; if (obj->isIndexed()) return JS_TRUE; } return JS_FALSE; } static JSBool array_defineGeneric(JSContext *cx, HandleObject obj, HandleId id, HandleValue value, JSPropertyOp getter, StrictPropertyOp setter, unsigned attrs) { if (JSID_IS_ATOM(id, cx->names().length)) return JS_TRUE; if (!obj->isDenseArray()) return baseops::DefineGeneric(cx, obj, id, value, getter, setter, attrs); do { uint32_t i = 0; // init to shut GCC up bool isIndex = js_IdIsIndex(id, &i); if (!isIndex || attrs != JSPROP_ENUMERATE) break; JSObject::EnsureDenseResult result = obj->ensureDenseArrayElements(cx, i, 1); if (result != JSObject::ED_OK) { if (result == JSObject::ED_FAILED) return false; JS_ASSERT(result == JSObject::ED_SPARSE); break; } if (i >= obj->getArrayLength()) obj->setDenseArrayLength(i + 1); JSObject::setDenseArrayElementWithType(cx, obj, i, value); return true; } while (false); AutoRooterGetterSetter gsRoot(cx, attrs, &getter, &setter); if (!JSObject::makeDenseArraySlow(cx, obj)) return false; return baseops::DefineGeneric(cx, obj, id, value, getter, setter, attrs); } static JSBool array_defineProperty(JSContext *cx, HandleObject obj, HandlePropertyName name, HandleValue value, JSPropertyOp getter, StrictPropertyOp setter, unsigned attrs) { Rooted id(cx, NameToId(name)); return array_defineGeneric(cx, obj, id, value, getter, setter, attrs); } namespace js { /* non-static for direct definition of array elements within the engine */ JSBool array_defineElement(JSContext *cx, HandleObject obj, uint32_t index, HandleValue value, PropertyOp getter, StrictPropertyOp setter, unsigned attrs) { if (!obj->isDenseArray()) return baseops::DefineElement(cx, obj, index, value, getter, setter, attrs); do { /* * UINT32_MAX is not an array index and must not affect the length * property, so specifically reject it. */ if (attrs != JSPROP_ENUMERATE || index == UINT32_MAX) break; JSObject::EnsureDenseResult result = obj->ensureDenseArrayElements(cx, index, 1); if (result != JSObject::ED_OK) { if (result == JSObject::ED_FAILED) return false; JS_ASSERT(result == JSObject::ED_SPARSE); break; } if (index >= obj->getArrayLength()) obj->setDenseArrayLength(index + 1); JSObject::setDenseArrayElementWithType(cx, obj, index, value); return true; } while (false); AutoRooterGetterSetter gsRoot(cx, attrs, &getter, &setter); if (!JSObject::makeDenseArraySlow(cx, obj)) return false; return baseops::DefineElement(cx, obj, index, value, getter, setter, attrs); } } // namespace js static JSBool array_defineSpecial(JSContext *cx, HandleObject obj, HandleSpecialId sid, HandleValue value, PropertyOp getter, StrictPropertyOp setter, unsigned attrs) { Rooted id(cx, SPECIALID_TO_JSID(sid)); return array_defineGeneric(cx, obj, id, value, getter, setter, attrs); } static JSBool array_getGenericAttributes(JSContext *cx, HandleObject obj, HandleId id, unsigned *attrsp) { *attrsp = JSID_IS_ATOM(id, cx->names().length) ? JSPROP_PERMANENT : JSPROP_ENUMERATE; return true; } static JSBool array_getPropertyAttributes(JSContext *cx, HandleObject obj, HandlePropertyName name, unsigned *attrsp) { *attrsp = (name == cx->names().length) ? JSPROP_PERMANENT : JSPROP_ENUMERATE; return true; } static JSBool array_getElementAttributes(JSContext *cx, HandleObject obj, uint32_t index, unsigned *attrsp) { *attrsp = JSPROP_ENUMERATE; return true; } static JSBool array_getSpecialAttributes(JSContext *cx, HandleObject obj, HandleSpecialId sid, unsigned *attrsp) { *attrsp = JSPROP_ENUMERATE; return true; } static JSBool array_setGenericAttributes(JSContext *cx, HandleObject obj, HandleId id, unsigned *attrsp) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_CANT_SET_ARRAY_ATTRS); return false; } static JSBool array_setPropertyAttributes(JSContext *cx, HandleObject obj, HandlePropertyName name, unsigned *attrsp) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_CANT_SET_ARRAY_ATTRS); return false; } static JSBool array_setElementAttributes(JSContext *cx, HandleObject obj, uint32_t index, unsigned *attrsp) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_CANT_SET_ARRAY_ATTRS); return false; } static JSBool array_setSpecialAttributes(JSContext *cx, HandleObject obj, HandleSpecialId sid, unsigned *attrsp) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_CANT_SET_ARRAY_ATTRS); return false; } static JSBool array_deleteProperty(JSContext *cx, HandleObject obj, HandlePropertyName name, MutableHandleValue rval, JSBool strict) { if (!obj->isDenseArray()) return baseops::DeleteProperty(cx, obj, name, rval, strict); if (name == cx->names().length) { rval.setBoolean(false); return true; } rval.setBoolean(true); return true; } namespace js { /* non-static for direct deletion of array elements within the engine */ JSBool array_deleteElement(JSContext *cx, HandleObject obj, uint32_t index, MutableHandleValue rval, JSBool strict) { if (!obj->isDenseArray()) return baseops::DeleteElement(cx, obj, index, rval, strict); if (index < obj->getDenseArrayInitializedLength()) { obj->markDenseArrayNotPacked(cx); obj->setDenseArrayElement(index, MagicValue(JS_ARRAY_HOLE)); } if (!js_SuppressDeletedElement(cx, obj, index)) return false; rval.setBoolean(true); return true; } } // namespace js static JSBool array_deleteSpecial(JSContext *cx, HandleObject obj, HandleSpecialId sid, MutableHandleValue rval, JSBool strict) { if (!obj->isDenseArray()) return baseops::DeleteSpecial(cx, obj, sid, rval, strict); rval.setBoolean(true); return true; } static void array_trace(JSTracer *trc, JSObject *obj) { JS_ASSERT(obj->isDenseArray()); uint32_t initLength = obj->getDenseArrayInitializedLength(); MarkArraySlots(trc, initLength, obj->getDenseArrayElements(), "element"); } Class js::ArrayClass = { "Array", Class::NON_NATIVE | JSCLASS_HAS_CACHED_PROTO(JSProto_Array), JS_PropertyStub, /* addProperty */ JS_PropertyStub, /* delProperty */ JS_PropertyStub, /* getProperty */ JS_StrictPropertyStub, /* setProperty */ JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub, NULL, NULL, /* checkAccess */ NULL, /* call */ NULL, /* construct */ NULL, /* hasInstance */ array_trace, /* trace */ { NULL, /* equality */ NULL, /* outerObject */ NULL, /* innerObject */ NULL, /* iteratorObject */ NULL, /* unused */ false, /* isWrappedNative */ }, { array_lookupGeneric, array_lookupProperty, array_lookupElement, array_lookupSpecial, array_defineGeneric, array_defineProperty, array_defineElement, array_defineSpecial, array_getGeneric, array_getProperty, array_getElement, NULL, /* getElementIfPresent, because this is hard for now for slow arrays */ array_getSpecial, array_setGeneric, array_setProperty, array_setElement, array_setSpecial, array_getGenericAttributes, array_getPropertyAttributes, array_getElementAttributes, array_getSpecialAttributes, array_setGenericAttributes, array_setPropertyAttributes, array_setElementAttributes, array_setSpecialAttributes, array_deleteProperty, array_deleteElement, array_deleteSpecial, NULL, /* enumerate */ NULL, /* typeOf */ NULL, /* thisObject */ } }; Class js::SlowArrayClass = { "Array", JSCLASS_HAS_CACHED_PROTO(JSProto_Array), slowarray_addProperty, JS_PropertyStub, /* delProperty */ JS_PropertyStub, /* getProperty */ JS_StrictPropertyStub, /* setProperty */ JS_EnumerateStub, JS_ResolveStub, JS_ConvertStub, NULL, NULL, /* checkAccess */ NULL, /* call */ NULL, /* construct */ NULL, /* hasInstance */ NULL, /* trace */ { NULL, /* equality */ NULL, /* outerObject */ NULL, /* innerObject */ NULL, /* iteratorObject */ NULL, /* unused */ false, /* isWrappedNative */ } }; bool JSObject::allocateSlowArrayElements(JSContext *cx) { JS_ASSERT(hasClass(&js::SlowArrayClass)); JS_ASSERT(elements == emptyObjectElements); ObjectElements *header = cx->new_(0, 0); if (!header) return false; elements = header->elements(); return true; } static bool AddLengthProperty(JSContext *cx, HandleObject obj) { /* * Add the 'length' property for a newly created or converted slow array, * and update the elements to be an empty array owned by the object. * The shared emptyObjectElements singleton cannot be used for slow arrays, * as accesses to 'length' will use the elements header. */ RootedId lengthId(cx, NameToId(cx->names().length)); JS_ASSERT(!obj->nativeLookup(cx, lengthId)); if (!obj->allocateSlowArrayElements(cx)) return false; return obj->addProperty(cx, lengthId, array_length_getter, array_length_setter, SHAPE_INVALID_SLOT, JSPROP_PERMANENT | JSPROP_SHARED, 0, 0); } /* * Convert an array object from fast-and-dense to slow-and-flexible. */ /* static */ bool JSObject::makeDenseArraySlow(JSContext *cx, HandleObject obj) { JS_ASSERT(obj->isDenseArray()); MarkTypeObjectFlags(cx, obj, OBJECT_FLAG_NON_PACKED_ARRAY | OBJECT_FLAG_NON_DENSE_ARRAY); uint32_t arrayCapacity = obj->getDenseArrayCapacity(); uint32_t arrayInitialized = obj->getDenseArrayInitializedLength(); /* * Get an allocated array of the existing elements, evicting from the fixed * slots if necessary. */ if (!obj->hasDynamicElements()) { if (!obj->growElements(cx, arrayCapacity)) return false; JS_ASSERT(obj->hasDynamicElements()); } /* Take ownership of the dense elements. */ HeapSlot *elems = obj->elements; /* Root all values in the array during conversion. */ AutoValueArray autoArray(cx, (Value *) elems, arrayInitialized); /* * Save old map now, before calling InitScopeForObject. We'll have to undo * on error. This is gross, but a better way is not obvious. Note: the * exact contents of the array are not preserved on error. */ js::Shape *oldShape = obj->lastProperty(); /* Create a native scope. */ gc::AllocKind kind = obj->getAllocKind(); Shape *shape = EmptyShape::getInitialShape(cx, &SlowArrayClass, obj->getProto(), oldShape->getObjectParent(), kind); if (!shape) return false; /* * In case an incremental GC is already running, we need to write barrier * the elements before (temporarily) destroying them. * * Note: this has to happen after getInitialShape (which can trigger * incremental GC) and *before* we overwrite shape, making us no longer a * dense array. */ if (obj->compartment()->needsBarrier()) obj->prepareElementRangeForOverwrite(0, arrayInitialized); obj->shape_ = shape; /* Reset to an empty dense array. */ obj->elements = emptyObjectElements; /* * Begin with the length property to share more of the property tree. * The getter/setter here will directly access the object's private value. */ if (!AddLengthProperty(cx, obj)) { obj->shape_ = oldShape; if (obj->elements != emptyObjectElements) js_free(obj->getElementsHeader()); obj->elements = elems; return false; } /* * Create new properties pointing to existing elements. Pack the array to * remove holes, so that shapes use successive slots (as for other objects). */ uint32_t next = 0; for (uint32_t i = 0; i < arrayInitialized; i++) { /* Dense array indexes can always fit in a jsid. */ jsid id; JS_ALWAYS_TRUE(ValueToId(cx, Int32Value(i), &id)); if (elems[i].isMagic(JS_ARRAY_HOLE)) continue; if (!obj->addDataProperty(cx, id, next, JSPROP_ENUMERATE)) { obj->shape_ = oldShape; js_free(obj->getElementsHeader()); obj->elements = elems; return false; } obj->initSlot(next, elems[i]); next++; } ObjectElements *oldheader = ObjectElements::fromElements(elems); obj->getElementsHeader()->length = oldheader->length; js_free(oldheader); return true; } #if JS_HAS_TOSOURCE JS_ALWAYS_INLINE bool IsArray(const Value &v) { return v.isObject() && v.toObject().isArray(); } JS_ALWAYS_INLINE bool array_toSource_impl(JSContext *cx, CallArgs args) { JS_ASSERT(IsArray(args.thisv())); Rooted obj(cx, &args.thisv().toObject()); RootedValue elt(cx); AutoCycleDetector detector(cx, obj); if (!detector.init()) return false; StringBuffer sb(cx); if (detector.foundCycle()) { if (!sb.append("[]")) return false; goto make_string; } if (!sb.append('[')) return false; uint32_t length; if (!GetLengthProperty(cx, obj, &length)) return false; for (uint32_t index = 0; index < length; index++) { JSBool hole; if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, index, &hole, &elt)) { return false; } /* Get element's character string. */ JSString *str; if (hole) { str = cx->runtime->emptyString; } else { str = js_ValueToSource(cx, elt); if (!str) return false; } /* Append element to buffer. */ if (!sb.append(str)) return false; if (index + 1 != length) { if (!sb.append(", ")) return false; } else if (hole) { if (!sb.append(',')) return false; } } /* Finalize the buffer. */ if (!sb.append(']')) return false; make_string: JSString *str = sb.finishString(); if (!str) return false; args.rval().setString(str); return true; } JSBool array_toSource(JSContext *cx, unsigned argc, Value *vp) { JS_CHECK_RECURSION(cx, return false); CallArgs args = CallArgsFromVp(argc, vp); return CallNonGenericMethod(cx, args); } #endif static bool array_join_sub(JSContext *cx, CallArgs &args, bool locale) { // This method is shared by Array.prototype.join and // Array.prototype.toLocaleString. The steps in ES5 are nearly the same, so // the annotations in this function apply to both toLocaleString and join. // 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; } // Steps 2 and 3 uint32_t length; if (!GetLengthProperty(cx, obj, &length)) return false; // Steps 4 and 5 RootedString sepstr(cx, NULL); if (!locale && args.hasDefined(0)) { sepstr = ToString(cx, args[0]); if (!sepstr) return false; } static const jschar comma = ','; const jschar *sep; size_t seplen; if (sepstr) { sep = NULL; seplen = sepstr->length(); } else { sep = , seplen = 1; } // Step 6 is implicit in the loops below StringBuffer sb(cx); // Various optimized versions of steps 7-10 if (!locale && !seplen && obj->isDenseArray() && !js_PrototypeHasIndexedProperties(obj)) { const Value *start = obj->getDenseArrayElements(); const Value *end = start + obj->getDenseArrayInitializedLength(); const Value *elem; for (elem = start; elem < end; elem++) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; /* * Object stringifying is slow; delegate it to a separate loop to * keep this one tight. */ if (elem->isObject()) break; if (!elem->isMagic(JS_ARRAY_HOLE) && !elem->isNullOrUndefined()) { if (!ValueToStringBuffer(cx, *elem, sb)) return false; } } RootedValue v(cx); for (uint32_t i = uint32_t(PointerRangeSize(start, elem)); i < length; i++) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; JSBool hole; if (!GetElement(cx, obj, i, &hole, &v)) return false; if (!hole && !v.isNullOrUndefined()) { if (!ValueToStringBuffer(cx, v, sb)) return false; } } } else { RootedValue elt(cx); for (uint32_t index = 0; index < length; index++) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; JSBool hole; if (!GetElement(cx, obj, index, &hole, &elt)) return false; if (!hole && !elt.isNullOrUndefined()) { if (locale) { JSObject *robj = ToObject(cx, elt); if (!robj) return false; RootedId id(cx, NameToId(cx->names().toLocaleString)); if (!robj->callMethod(cx, id, 0, NULL, &elt)) return false; } if (!ValueToStringBuffer(cx, elt, sb)) return false; } if (index + 1 != length) { const jschar *sepchars = sep ? sep : sepstr->getChars(cx); if (!sepchars || !sb.append(sepchars, seplen)) return false; } } } // Step 11 JSString *str = sb.finishString(); if (!str) return false; args.rval().setString(str); return true; } /* ES5 15.4.4.2. NB: The algorithm here differs from the one in ES3. */ static JSBool array_toString(JSContext *cx, unsigned argc, Value *vp) { JS_CHECK_RECURSION(cx, return false); CallArgs args = CallArgsFromVp(argc, vp); RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; RootedValue join(cx, args.calleev()); if (!JSObject::getProperty(cx, obj, obj, cx->names().join, &join)) return false; if (!js_IsCallable(join)) { JSString *str = obj_toStringHelper(cx, obj); if (!str) return false; args.rval().setString(str); return true; } InvokeArgsGuard ag; if (!cx->stack.pushInvokeArgs(cx, 0, &ag)) return false; ag.setCallee(join); ag.setThis(ObjectValue(*obj)); /* Do the call. */ if (!Invoke(cx, ag)) return false; args.rval().set(ag.rval()); return true; } /* ES5 15.4.4.3 */ static JSBool array_toLocaleString(JSContext *cx, unsigned argc, Value *vp) { JS_CHECK_RECURSION(cx, return false); CallArgs args = CallArgsFromVp(argc, vp); return array_join_sub(cx, args, true); } /* ES5 15.4.4.5 */ static JSBool array_join(JSContext *cx, unsigned argc, Value *vp) { JS_CHECK_RECURSION(cx, return false); CallArgs args = CallArgsFromVp(argc, vp); return array_join_sub(cx, args, false); } static inline bool InitArrayTypes(JSContext *cx, TypeObject *type, const Value *vector, unsigned count) { if (cx->typeInferenceEnabled() && !type->unknownProperties()) { AutoEnterTypeInference enter(cx); TypeSet *types = type->getProperty(cx, JSID_VOID, true); if (!types) return false; for (unsigned i = 0; i < count; i++) { if (vector[i].isMagic(JS_ARRAY_HOLE)) continue; Type valtype = GetValueType(cx, vector[i]); types->addType(cx, valtype); } } return true; } enum ShouldUpdateTypes { UpdateTypes = true, DontUpdateTypes = false }; /* vector must point to rooted memory. */ static bool InitArrayElements(JSContext *cx, HandleObject obj, uint32_t start, uint32_t count, const Value *vector, ShouldUpdateTypes updateTypes) { JS_ASSERT(count <= MAX_ARRAY_INDEX); if (count == 0) return true; if (updateTypes && !InitArrayTypes(cx, obj->getType(cx), vector, count)) return false; /* * Optimize for dense arrays so long as adding the given set of elements * wouldn't otherwise make the array slow. */ do { if (!obj->isDenseArray()) break; if (js_PrototypeHasIndexedProperties(obj)) break; JSObject::EnsureDenseResult result = obj->ensureDenseArrayElements(cx, start, count); if (result != JSObject::ED_OK) { if (result == JSObject::ED_FAILED) return false; JS_ASSERT(result == JSObject::ED_SPARSE); break; } uint32_t newlen = start + count; if (newlen > obj->getArrayLength()) obj->setDenseArrayLength(newlen); JS_ASSERT(count < UINT32_MAX / sizeof(Value)); obj->copyDenseArrayElements(start, vector, count); JS_ASSERT_IF(count != 0, !obj->getDenseArrayElement(newlen - 1).isMagic(JS_ARRAY_HOLE)); return true; } while (false); const Value* end = vector + count; while (vector < end && start <= MAX_ARRAY_INDEX) { if (!JS_CHECK_OPERATION_LIMIT(cx) || !SetArrayElement(cx, obj, start++, HandleValue::fromMarkedLocation(vector++))) { return false; } } if (vector == end) return true; /* Finish out any remaining elements past the max array index. */ if (obj->isDenseArray() && !JSObject::makeDenseArraySlow(cx, obj)) return false; JS_ASSERT(start == MAX_ARRAY_INDEX + 1); RootedValue value(cx); RootedId id(cx); Value idval = DoubleValue(MAX_ARRAY_INDEX + 1); do { value = *vector++; if (!ValueToId(cx, idval, id.address()) || !JSObject::setGeneric(cx, obj, obj, id, &value, true)) { return false; } idval.getDoubleRef() += 1; } while (vector != end); return true; } static JSBool array_reverse(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; uint32_t len; if (!GetLengthProperty(cx, obj, &len)) return false; do { if (!obj->isDenseArray()) break; if (js_PrototypeHasIndexedProperties(obj)) break; /* An empty array or an array with no elements is already reversed. */ if (len == 0 || obj->getDenseArrayCapacity() == 0) { args.rval().setObject(*obj); return true; } /* * 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. */ JSObject::EnsureDenseResult result = obj->ensureDenseArrayElements(cx, len, 0); if (result != JSObject::ED_OK) { if (result == JSObject::ED_FAILED) return false; JS_ASSERT(result == JSObject::ED_SPARSE); break; } /* Fill out the array's initialized length to its proper length. */ obj->ensureDenseArrayInitializedLength(cx, len, 0); uint32_t lo = 0, hi = len - 1; for (; lo < hi; lo++, hi--) { Value origlo = obj->getDenseArrayElement(lo); Value orighi = obj->getDenseArrayElement(hi); obj->setDenseArrayElement(lo, orighi); if (orighi.isMagic(JS_ARRAY_HOLE) && !js_SuppressDeletedProperty(cx, obj, INT_TO_JSID(lo))) { return false; } obj->setDenseArrayElement(hi, origlo); if (origlo.isMagic(JS_ARRAY_HOLE) && !js_SuppressDeletedProperty(cx, obj, INT_TO_JSID(hi))) { return false; } } /* * 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 true; } while (false); RootedValue lowval(cx), hival(cx); for (uint32_t i = 0, half = len / 2; i < half; i++) { JSBool hole, hole2; if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, i, &hole, &lowval) || !GetElement(cx, obj, len - i - 1, &hole2, &hival) || !SetOrDeleteArrayElement(cx, obj, len - i - 1, hole, lowval) || !SetOrDeleteArrayElement(cx, obj, i, hole2, hival)) { return false; } } args.rval().setObject(*obj); return true; } namespace { inline bool CompareStringValues(JSContext *cx, const Value &a, const Value &b, bool *lessOrEqualp) { if (!JS_CHECK_OPERATION_LIMIT(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 uint64_t const 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, t; JS_CEILING_LOG2(log2, n); t = log2 * 1233 >> 12; return t - (n < powersOf10[t]) + 1; } static JS_ALWAYS_INLINE uint32_t NegateNegativeInt32(int32_t i) { /* * We cannot simply return '-i' because this is undefined for INT32_MIN. * 2s complement does actually give us what we want, however. That is, * ~0x80000000 + 1 = 0x80000000 which is correct when interpreted as a * uint32_t. To avoid undefined behavior, we write out 2s complement * explicitly and rely on the peephole optimizer to generate 'neg'. */ return ~uint32_t(i) + 1; } inline bool CompareLexicographicInt32(JSContext *cx, 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, buint; if (aint >= 0) { auint = aint; buint = bint; } else { auint = NegateNegativeInt32(aint); buint = NegateNegativeInt32(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) { JS_ASSERT((digitsa - digitsb) < ArrayLength(powersOf10)); *lessOrEqualp = (uint64_t(auint) < uint64_t(buint) * powersOf10[digitsa - digitsb]); } else { /* if (digitsb > digitsa) */ JS_ASSERT((digitsb - digitsa) < ArrayLength(powersOf10)); *lessOrEqualp = (uint64_t(auint) * powersOf10[digitsb - digitsa] <= uint64_t(buint)); } } return true; } inline bool CompareSubStringValues(JSContext *cx, const jschar *s1, size_t l1, const jschar *s2, size_t l2, bool *lessOrEqualp) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; int32_t result; if (!s1 || !s2 || !CompareChars(s1, l1, s2, l2, &result)) return false; *lessOrEqualp = (result <= 0); return true; } struct SortComparatorStrings { JSContext *const cx; SortComparatorStrings(JSContext *cx) : cx(cx) {} bool operator()(const Value &a, const Value &b, bool *lessOrEqualp) { return CompareStringValues(cx, a, b, lessOrEqualp); } }; struct SortComparatorLexicographicInt32 { JSContext *const cx; SortComparatorLexicographicInt32(JSContext *cx) : cx(cx) {} bool operator()(const Value &a, const Value &b, bool *lessOrEqualp) { return CompareLexicographicInt32(cx, 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) { return CompareSubStringValues(cx, sb.begin() + a.charsBegin, a.charsEnd - a.charsBegin, sb.begin() + b.charsBegin, b.charsEnd - b.charsBegin, lessOrEqualp); } }; struct SortComparatorFunction { JSContext *const cx; const Value &fval; InvokeArgsGuard &ag; SortComparatorFunction(JSContext *cx, const Value &fval, InvokeArgsGuard &ag) : cx(cx), fval(fval), ag(ag) { } bool operator()(const Value &a, const Value &b, bool *lessOrEqualp); }; bool SortComparatorFunction::operator()(const Value &a, const Value &b, bool *lessOrEqualp) { /* * array_sort deals with holes and undefs on its own and they should not * come here. */ JS_ASSERT(!a.isMagic() && !a.isUndefined()); JS_ASSERT(!a.isMagic() && !b.isUndefined()); if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 2, &ag)) return false; ag.setCallee(fval); ag.setThis(UndefinedValue()); ag[0] = a; ag[1] = b; if (!Invoke(cx, ag)) return false; double cmp; if (!ToNumber(cx, ag.rval(), &cmp)) return false; /* * XXX eport some kind of error here if cmp is NaN? ECMA talks about * 'consistent compare functions' that don't return NaN, but is silent * about what the result should be. So we currently ignore it. */ *lessOrEqualp = (MOZ_DOUBLE_IS_NaN(cmp) || cmp <= 0); return true; } } /* namespace anonymous */ JSBool js::array_sort(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); RootedValue fvalRoot(cx); Value &fval = fvalRoot.get(); if (args.hasDefined(0)) { if (args[0].isPrimitive()) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_BAD_SORT_ARG); return false; } fval = args[0]; /* non-default compare function */ } else { fval.setNull(); } RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; uint32_t len; if (!GetLengthProperty(cx, obj, &len)) return false; if (len == 0) { args.rval().setObject(*obj); return true; } /* * 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))) { js_ReportAllocationOverflow(cx); return false; } #endif /* * Initialize vec as a root. We will clear elements of vec one by * one while increasing the rooted amount of vec when we know that the * property at the corresponding index exists and its value must be rooted. * * In this way when sorting a huge mostly sparse array we will not * access the tail of vec corresponding to properties that do not * exist, allowing OS to avoiding committing RAM. See bug 330812. */ size_t n, undefs; { AutoValueVector vec(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); for (uint32_t i = 0; i < len; i++) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; /* Clear vec[newlen] before including it in the rooted set. */ JSBool hole; if (!GetElement(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(); } n = vec.length(); if (n == 0) { args.rval().setObject(*obj); return true; /* The array has only holes and undefs. */ } JS_ALWAYS_TRUE(vec.resize(n * 2)); /* Here len == n + undefs + number_of_holes. */ Value *result = vec.begin(); if (fval.isNull()) { /* * Sort using the default comparator converting all elements to * strings. */ if (allStrings) { if (!MergeSort(vec.begin(), n, vec.begin() + n, SortComparatorStrings(cx))) return false; } else if (allInts) { if (!MergeSort(vec.begin(), n, vec.begin() + n, SortComparatorLexicographicInt32(cx))) { return false; } } else { /* * Convert all elements to a jschar array in StringBuffer. * Store the index and length of each stringified element with * the corresponding index of the element in the array. Sort * the stringified elements and with this result order the * original array. */ StringBuffer sb(cx); Vector strElements(cx); if (!strElements.reserve(2 * n)) return false; size_t cursor = 0; for (size_t i = 0; i < n; i++) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; if (!ValueToStringBuffer(cx, vec[i], sb)) return false; StringifiedElement el = { cursor, sb.length(), i }; strElements.infallibleAppend(el); cursor = sb.length(); } /* Resize strElements so we can perform the sorting */ JS_ALWAYS_TRUE(strElements.resize(2 * n)); if (!MergeSort(strElements.begin(), n, strElements.begin() + n, SortComparatorStringifiedElements(cx, sb))) { return false; } /* Order vec[n:2n-1] using strElements.index */ for (size_t i = 0; i < n; i ++) vec[n + i] = vec[strElements[i].elementIndex]; result = vec.begin() + n; } } else { InvokeArgsGuard args; if (!MergeSort(vec.begin(), n, vec.begin() + n, SortComparatorFunction(cx, fval, args))) { return false; } } if (!InitArrayElements(cx, obj, 0, uint32_t(n), result, DontUpdateTypes)) return false; } /* Set undefs that sorted after the rest of elements. */ while (undefs != 0) { --undefs; RootedValue undefinedValue(cx); if (!JS_CHECK_OPERATION_LIMIT(cx) || !SetArrayElement(cx, obj, n++, undefinedValue)) return false; } /* Re-create any holes that sorted to the end of the array. */ while (len > n) { if (!JS_CHECK_OPERATION_LIMIT(cx) || DeleteArrayElement(cx, obj, --len, true) < 0) return false; } args.rval().setObject(*obj); return true; } /* * Perl-inspired push, pop, shift, unshift, and splice methods. */ static bool array_push_slowly(JSContext *cx, HandleObject obj, CallArgs &args) { uint32_t length; if (!GetLengthProperty(cx, obj, &length)) return false; if (!InitArrayElements(cx, obj, length, args.length(), args.array(), UpdateTypes)) return false; /* Per ECMA-262, return the new array length. */ double newlength = length + double(args.length()); args.rval().setNumber(newlength); return SetLengthProperty(cx, obj, newlength); } static bool array_push1_dense(JSContext* cx, HandleObject obj, CallArgs &args) { JS_ASSERT(args.length() == 1); uint32_t length = obj->getArrayLength(); JSObject::EnsureDenseResult result = obj->ensureDenseArrayElements(cx, length, 1); if (result != JSObject::ED_OK) { if (result == JSObject::ED_FAILED) return false; JS_ASSERT(result == JSObject::ED_SPARSE); if (!JSObject::makeDenseArraySlow(cx, obj)) return false; return array_push_slowly(cx, obj, args); } obj->setDenseArrayLength(length + 1); JSObject::setDenseArrayElementWithType(cx, obj, length, args[0]); args.rval().setNumber(obj->getArrayLength()); return true; } JS_ALWAYS_INLINE JSBool NewbornArrayPushImpl(JSContext *cx, HandleObject obj, const Value &v) { JS_ASSERT(!v.isMagic()); uint32_t length = obj->getArrayLength(); if (obj->isSlowArray()) { /* This can happen in one evil case. See bug 630377. */ RootedId id(cx); RootedValue nv(cx, v); return IndexToId(cx, length, id.address()) && baseops::DefineGeneric(cx, obj, id, nv, NULL, NULL, JSPROP_ENUMERATE); } JS_ASSERT(obj->isDenseArray()); JS_ASSERT(length <= obj->getDenseArrayCapacity()); if (!obj->ensureElements(cx, length + 1)) return false; obj->setDenseArrayInitializedLength(length + 1); obj->setDenseArrayLength(length + 1); JSObject::initDenseArrayElementWithType(cx, obj, length, v); return true; } JSBool js_NewbornArrayPush(JSContext *cx, HandleObject obj, const Value &vp) { return NewbornArrayPushImpl(cx, obj, vp); } JSBool js::array_push(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; /* Insist on one argument and obj of the expected class. */ if (args.length() != 1 || !obj->isDenseArray()) return array_push_slowly(cx, obj, args); return array_push1_dense(cx, obj, args); } static JSBool array_pop_slowly(JSContext *cx, HandleObject obj, CallArgs &args) { uint32_t index; if (!GetLengthProperty(cx, obj, &index)) return false; if (index == 0) { args.rval().setUndefined(); return SetLengthProperty(cx, obj, index); } index--; JSBool hole; RootedValue elt(cx); if (!GetElement(cx, obj, index, &hole, &elt)) return false; if (!hole && DeleteArrayElement(cx, obj, index, true) < 0) return false; args.rval().set(elt); return SetLengthProperty(cx, obj, index); } static JSBool array_pop_dense(JSContext *cx, HandleObject obj, CallArgs &args) { uint32_t index = obj->getArrayLength(); if (index == 0) { args.rval().setUndefined(); return true; } index--; JSBool hole; RootedValue elt(cx); if (!GetElement(cx, obj, index, &hole, &elt)) return false; if (!hole && DeleteArrayElement(cx, obj, index, true) < 0) return false; args.rval().set(elt); // obj may not be a dense array any more, e.g. if the element was a missing // and a getter supplied by the prototype modified the object. if (obj->isDenseArray()) { if (obj->getDenseArrayInitializedLength() > index) obj->setDenseArrayInitializedLength(index); JSObject::setArrayLength(cx, obj, index); return true; } return SetLengthProperty(cx, obj, index); } JSBool js::array_pop(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; if (obj->isDenseArray()) return array_pop_dense(cx, obj, args); return array_pop_slowly(cx, obj, args); } void js::ArrayShiftMoveElements(JSObject *obj) { JS_ASSERT(obj->isDenseArray()); /* * At this point the length and initialized length have already been * decremented and the result fetched, so just shift the array elements * themselves. */ uint32_t initlen = obj->getDenseArrayInitializedLength(); obj->moveDenseArrayElementsUnbarriered(0, 1, initlen); } #ifdef JS_METHODJIT void JS_FASTCALL mjit::stubs::ArrayShift(VMFrame &f) { JSObject *obj = &f.regs.sp[-1].toObject(); ArrayShiftMoveElements(obj); } #endif /* JS_METHODJIT */ JSBool js::array_shift(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return JS_FALSE; uint32_t length; if (!GetLengthProperty(cx, obj, &length)) return JS_FALSE; if (length == 0) { args.rval().setUndefined(); } else { length--; if (obj->isDenseArray() && !js_PrototypeHasIndexedProperties(obj) && length < obj->getDenseArrayCapacity() && 0 < obj->getDenseArrayInitializedLength()) { args.rval().set(obj->getDenseArrayElement(0)); if (args.rval().isMagic(JS_ARRAY_HOLE)) args.rval().setUndefined(); obj->moveDenseArrayElements(0, 1, obj->getDenseArrayInitializedLength() - 1); obj->setDenseArrayInitializedLength(obj->getDenseArrayInitializedLength() - 1); JSObject::setArrayLength(cx, obj, length); if (!js_SuppressDeletedProperty(cx, obj, INT_TO_JSID(length))) return JS_FALSE; return JS_TRUE; } JSBool hole; if (!GetElement(cx, obj, 0u, &hole, args.rval())) return JS_FALSE; /* Slide down the array above the first element. */ RootedValue value(cx); for (uint32_t i = 0; i < length; i++) { if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, i + 1, &hole, &value) || !SetOrDeleteArrayElement(cx, obj, i, hole, value)) { return JS_FALSE; } } /* Delete the only or last element when it exists. */ if (!hole && DeleteArrayElement(cx, obj, length, true) < 0) return JS_FALSE; } return SetLengthProperty(cx, obj, length); } static JSBool array_unshift(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; uint32_t length; if (!GetLengthProperty(cx, obj, &length)) return JS_FALSE; double newlen = length; if (args.length() > 0) { /* Slide up the array to make room for all args at the bottom. */ if (length > 0) { bool optimized = false; do { if (!obj->isDenseArray()) break; if (js_PrototypeHasIndexedProperties(obj)) break; JSObject::EnsureDenseResult result = obj->ensureDenseArrayElements(cx, length, args.length()); if (result != JSObject::ED_OK) { if (result == JSObject::ED_FAILED) return false; JS_ASSERT(result == JSObject::ED_SPARSE); break; } obj->moveDenseArrayElements(args.length(), 0, length); for (uint32_t i = 0; i < args.length(); i++) obj->setDenseArrayElement(i, MagicValue(JS_ARRAY_HOLE)); optimized = true; } while (false); if (!optimized) { double last = length; double upperIndex = last + args.length(); RootedValue value(cx); do { --last, --upperIndex; JSBool hole; if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, last, &hole, &value) || !SetOrDeleteArrayElement(cx, obj, upperIndex, hole, value)) { return JS_FALSE; } } while (last != 0); } } /* Copy from args to the bottom of the array. */ if (!InitArrayElements(cx, obj, 0, args.length(), args.array(), UpdateTypes)) return JS_FALSE; newlen += args.length(); } if (!SetLengthProperty(cx, obj, newlen)) return JS_FALSE; /* Follow Perl by returning the new array length. */ args.rval().setNumber(newlen); return JS_TRUE; } static inline void TryReuseArrayType(JSObject *obj, JSObject *nobj) { /* * Try to change the type of a newly created array nobj to the same type * as obj. This can only be performed if the original object is an array * and has the same prototype. */ JS_ASSERT(nobj->isDenseArray()); JS_ASSERT(nobj->getProto()->hasNewType(nobj->type())); if (obj->isArray() && !obj->hasSingletonType() && obj->getProto() == nobj->getProto()) nobj->setType(obj->type()); } /* * Returns true if this is a dense array whose |count| properties starting from * |startingIndex| 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. */ static inline bool CanOptimizeForDenseStorage(JSObject *arr, uint32_t startingIndex, uint32_t count, JSContext *cx) { /* If the desired properties overflow dense storage, we can't optimize. */ if (UINT32_MAX - startingIndex < count) return false; /* There's no optimizing possible if it's not a dense array. */ if (!arr->isDenseArray()) return false; /* * Don't optimize if the array might be in the midst of iteration. We * rely on this to be able to safely move dense array elements around with * just a memmove (see JSObject::moveDenseArrayElements), without worrying * about updating any in-progress enumerators for properties implicitly * deleted if a hole is moved from one location to another location not yet * visited. See bug 690622. * * Another potential wrinkle: what if the enumeration is happening on an * object which merely has |arr| on its prototype chain? It turns out this * case can't happen, because any dense array used as the prototype of * another object is first slowified, for type inference's sake. */ if (JS_UNLIKELY(arr->getType(cx)->hasAllFlags(OBJECT_FLAG_ITERATED))) return false; /* Now just watch out for getters and setters along the prototype chain. */ return !js_PrototypeHasIndexedProperties(arr) && startingIndex + count <= arr->getDenseArrayInitializedLength(); } /* ES5 15.4.4.12. */ static JSBool array_splice(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); /* Step 1. */ RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; /* Steps 3-4. */ uint32_t len; if (!GetLengthProperty(cx, obj, &len)) return false; /* Step 5. */ double relativeStart; if (!ToInteger(cx, argc >= 1 ? args[0] : UndefinedValue(), &relativeStart)) return false; /* Step 6. */ uint32_t actualStart; if (relativeStart < 0) actualStart = Max(len + relativeStart, 0.0); else actualStart = Min(relativeStart, double(len)); /* Step 7. */ uint32_t actualDeleteCount; if (argc != 1) { double deleteCountDouble; if (!ToInteger(cx, argc >= 2 ? args[1] : Int32Value(0), &deleteCountDouble)) return false; actualDeleteCount = Min(Max(deleteCountDouble, 0.0), double(len - actualStart)); } else { /* * Non-standard: if start was specified but deleteCount was omitted, * delete to the end of the array. See bug 668024 for discussion. */ actualDeleteCount = len - actualStart; } JS_ASSERT(len - actualStart >= actualDeleteCount); /* Steps 2, 8-9. */ RootedObject arr(cx); if (CanOptimizeForDenseStorage(obj, actualStart, actualDeleteCount, cx)) { arr = NewDenseCopiedArray(cx, actualDeleteCount, obj->getDenseArrayElements() + actualStart); if (!arr) return false; TryReuseArrayType(obj, arr); } else { arr = NewDenseAllocatedArray(cx, actualDeleteCount); if (!arr) return false; TryReuseArrayType(obj, arr); RootedValue fromValue(cx); for (uint32_t k = 0; k < actualDeleteCount; k++) { JSBool hole; if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, actualStart + k, &hole, &fromValue) || (!hole && !JSObject::defineElement(cx, arr, k, fromValue))) { return false; } } } /* Step 11. */ uint32_t itemCount = (argc >= 2) ? (argc - 2) : 0; if (itemCount < actualDeleteCount) { /* Step 12: the array is being shrunk. */ uint32_t sourceIndex = actualStart + actualDeleteCount; uint32_t targetIndex = actualStart + itemCount; uint32_t finalLength = len - actualDeleteCount + itemCount; if (CanOptimizeForDenseStorage(obj, 0, len, cx)) { /* Steps 12(a)-(b). */ obj->moveDenseArrayElements(targetIndex, sourceIndex, len - sourceIndex); /* * Update the initialized length. Do so before shrinking so that we * can apply the write barrier to the old slots. */ if (cx->typeInferenceEnabled()) obj->setDenseArrayInitializedLength(finalLength); /* Steps 12(c)-(d). */ obj->shrinkElements(cx, finalLength); /* Fix running enumerators for the deleted items. */ if (!js_SuppressDeletedElements(cx, obj, finalLength, len)) return false; } 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 JS_CHECK_OPERATION_LIMIT handle the * fallout. */ /* Steps 12(a)-(b). */ RootedValue fromValue(cx); for (uint32_t from = sourceIndex, to = targetIndex; from < len; from++, to++) { JSBool hole; if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, from, &hole, &fromValue) || !SetOrDeleteArrayElement(cx, obj, to, hole, fromValue)) { return false; } } /* Steps 12(c)-(d). */ for (uint32_t k = len; k > finalLength; k--) { if (DeleteArrayElement(cx, obj, k - 1, true) < 0) return false; } } } else if (itemCount > actualDeleteCount) { /* Step 13. */ /* * Optimize only if the array is already dense and we can extend it to * its new length. */ if (obj->isDenseArray()) { JSObject::EnsureDenseResult res = obj->ensureDenseArrayElements(cx, obj->getArrayLength(), itemCount - actualDeleteCount); if (res == JSObject::ED_FAILED) return false; if (res == JSObject::ED_SPARSE) { if (!JSObject::makeDenseArraySlow(cx, obj)) return false; } else { JS_ASSERT(res == JSObject::ED_OK); } } if (CanOptimizeForDenseStorage(obj, len, itemCount - actualDeleteCount, cx)) { obj->moveDenseArrayElements(actualStart + itemCount, actualStart + actualDeleteCount, len - (actualStart + actualDeleteCount)); if (cx->typeInferenceEnabled()) obj->setDenseArrayInitializedLength(len + itemCount - actualDeleteCount); } else { RootedValue fromValue(cx); for (double k = len - actualDeleteCount; k > actualStart; k--) { double from = k + actualDeleteCount - 1; double to = k + itemCount - 1; JSBool hole; if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, from, &hole, &fromValue) || !SetOrDeleteArrayElement(cx, obj, to, hole, fromValue)) { return false; } } } } /* Step 10. */ Value *items = args.array() + 2; /* Steps 14-15. */ for (uint32_t k = actualStart, i = 0; i < itemCount; i++, k++) { if (!SetArrayElement(cx, obj, k, HandleValue::fromMarkedLocation(&items[i]))) return false; } /* Step 16. */ double finalLength = double(len) - actualDeleteCount + itemCount; if (!SetLengthProperty(cx, obj, finalLength)) return false; /* Step 17. */ args.rval().setObject(*arr); return true; } #ifdef JS_METHODJIT void JS_FASTCALL mjit::stubs::ArrayConcatTwoArrays(VMFrame &f) { JSObject *result = &f.regs.sp[-3].toObject(); JSObject *obj1 = &f.regs.sp[-2].toObject(); JSObject *obj2 = &f.regs.sp[-1].toObject(); JS_ASSERT(result->isDenseArray() && obj1->isDenseArray() && obj2->isDenseArray()); uint32_t initlen1 = obj1->getDenseArrayInitializedLength(); JS_ASSERT(initlen1 == obj1->getArrayLength()); uint32_t initlen2 = obj2->getDenseArrayInitializedLength(); JS_ASSERT(initlen2 == obj2->getArrayLength()); /* No overflow here due to nslots limit. */ uint32_t len = initlen1 + initlen2; if (!result->ensureElements(f.cx, len)) THROW(); JS_ASSERT(!result->getDenseArrayInitializedLength()); result->setDenseArrayInitializedLength(len); result->initDenseArrayElements(0, obj1->getDenseArrayElements(), initlen1); result->initDenseArrayElements(initlen1, obj2->getDenseArrayElements(), initlen2); result->setDenseArrayLength(len); } #endif /* JS_METHODJIT */ /* * Python-esque sequence operations. */ JSBool js::array_concat(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); /* Treat our |this| object as the first argument; see ECMA 15.4.4.4. */ Value *p = args.array() - 1; /* Create a new Array object and root it using *vp. */ RootedObject aobj(cx, ToObject(cx, args.thisv())); if (!aobj) return false; RootedObject nobj(cx); uint32_t length; if (aobj->isDenseArray()) { length = aobj->getArrayLength(); const Value *vector = aobj->getDenseArrayElements(); uint32_t initlen = aobj->getDenseArrayInitializedLength(); nobj = NewDenseCopiedArray(cx, initlen, vector); if (!nobj) return JS_FALSE; TryReuseArrayType(aobj, nobj); JSObject::setArrayLength(cx, nobj, length); args.rval().setObject(*nobj); if (argc == 0) return JS_TRUE; argc--; p++; } else { nobj = NewDenseEmptyArray(cx); if (!nobj) return JS_FALSE; args.rval().setObject(*nobj); length = 0; } /* Loop over [0, argc] to concat args into nobj, expanding all Arrays. */ for (unsigned i = 0; i <= argc; i++) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; HandleValue v = HandleValue::fromMarkedLocation(&p[i]); if (v.isObject()) { RootedObject obj(cx, &v.toObject()); if (ObjectClassIs(*obj, ESClass_Array, cx)) { uint32_t alength; if (!GetLengthProperty(cx, obj, &alength)) return false; RootedValue tmp(cx); for (uint32_t slot = 0; slot < alength; slot++) { JSBool hole; if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, slot, &hole, &tmp)) return false; /* * Per ECMA 262, 15.4.4.4, step 9, ignore nonexistent * properties. */ if (!hole && !SetArrayElement(cx, nobj, length + slot, tmp)) return false; } length += alength; continue; } } if (!SetArrayElement(cx, nobj, length, v)) return false; length++; } return SetLengthProperty(cx, nobj, length); } static JSBool array_slice(JSContext *cx, unsigned argc, Value *vp) { uint32_t length, begin, end, slot; JSBool hole; CallArgs args = CallArgsFromVp(argc, vp); RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; if (!GetLengthProperty(cx, obj, &length)) return JS_FALSE; begin = 0; end = length; if (args.length() > 0) { double d; if (!ToInteger(cx, args[0], &d)) return false; if (d < 0) { d += length; if (d < 0) d = 0; } else if (d > length) { d = length; } begin = (uint32_t)d; if (args.hasDefined(1)) { if (!ToInteger(cx, args[1], &d)) return false; if (d < 0) { d += length; if (d < 0) d = 0; } else if (d > length) { d = length; } end = (uint32_t)d; } } if (begin > end) begin = end; RootedObject nobj(cx); if (obj->isDenseArray() && end <= obj->getDenseArrayInitializedLength() && !js_PrototypeHasIndexedProperties(obj)) { nobj = NewDenseCopiedArray(cx, end - begin, obj->getDenseArrayElements() + begin); if (!nobj) return JS_FALSE; TryReuseArrayType(obj, nobj); args.rval().setObject(*nobj); return JS_TRUE; } nobj = NewDenseAllocatedArray(cx, end - begin); if (!nobj) return JS_FALSE; TryReuseArrayType(obj, nobj); RootedValue value(cx); for (slot = begin; slot < end; slot++) { if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, slot, &hole, &value)) { return JS_FALSE; } if (!hole && !SetArrayElement(cx, nobj, slot - begin, value)) return JS_FALSE; } args.rval().setObject(*nobj); return JS_TRUE; } enum IndexOfKind { IndexOf, LastIndexOf }; static JSBool array_indexOfHelper(JSContext *cx, IndexOfKind mode, CallArgs &args) { uint32_t length, i, stop; int direction; JSBool hole; RootedValue tosearch(cx), elt(cx); RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; if (!GetLengthProperty(cx, obj, &length)) return JS_FALSE; if (length == 0) goto not_found; if (args.length() <= 1) { i = (mode == LastIndexOf) ? length - 1 : 0; tosearch = (args.length() != 0) ? args[0] : UndefinedValue(); } else { double start; tosearch = args[0]; if (!ToInteger(cx, args[1], &start)) return false; if (start < 0) { start += length; if (start < 0) { if (mode == LastIndexOf) goto not_found; i = 0; } else { i = (uint32_t)start; } } else if (start >= length) { if (mode == IndexOf) goto not_found; i = length - 1; } else { i = (uint32_t)start; } } if (mode == LastIndexOf) { stop = 0; direction = -1; } else { stop = length - 1; direction = 1; } for (;;) { if (!JS_CHECK_OPERATION_LIMIT(cx) || !GetElement(cx, obj, (uint32_t)i, &hole, &elt)) { return JS_FALSE; } if (!hole) { bool equal; if (!StrictlyEqual(cx, elt, tosearch, &equal)) return false; if (equal) { args.rval().setNumber(i); return true; } } if (i == stop) goto not_found; i += direction; } not_found: args.rval().setInt32(-1); return JS_TRUE; } static JSBool array_indexOf(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); return array_indexOfHelper(cx, IndexOf, args); } static JSBool array_lastIndexOf(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); return array_indexOfHelper(cx, LastIndexOf, args); } /* ECMA 15.4.4.16-15.4.4.18. */ class ArrayForEachBehavior { public: static bool shouldExit(MutableHandleValue callbackRval, MutableHandleValue rval) { return false; } static Value lateExitValue() { return UndefinedValue(); } }; class ArrayEveryBehavior { public: static bool shouldExit(MutableHandleValue callbackRval, MutableHandleValue rval) { if (!ToBoolean(callbackRval)) { rval.setBoolean(false); return true; } return false; } static Value lateExitValue() { return BooleanValue(true); } }; class ArraySomeBehavior { public: static bool shouldExit(MutableHandleValue callbackRval, MutableHandleValue rval) { if (ToBoolean(callbackRval)) { rval.setBoolean(true); return true; } return false; } static Value lateExitValue() { return BooleanValue(false); } }; template static inline bool array_readonlyCommon(JSContext *cx, CallArgs &args) { /* Step 1. */ RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; /* Step 2-3. */ uint32_t len; if (!GetLengthProperty(cx, obj, &len)) return false; /* Step 4. */ if (args.length() == 0) { js_ReportMissingArg(cx, args.calleev(), 0); return false; } RootedObject callable(cx, ValueToCallable(cx, &args[0])); if (!callable) return false; /* Step 5. */ Value thisv = args.length() >= 2 ? args[1] : UndefinedValue(); /* Step 6. */ uint32_t k = 0; /* Step 7. */ RootedValue kValue(cx); InvokeArgsGuard ag; while (k < len) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; /* Step a, b, and c.i. */ JSBool kNotPresent; if (!GetElement(cx, obj, k, &kNotPresent, &kValue)) return false; /* Step c.ii-iii. */ if (!kNotPresent) { if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 3, &ag)) return false; ag.setCallee(ObjectValue(*callable)); ag.setThis(thisv); ag[0] = kValue; ag[1] = NumberValue(k); ag[2] = ObjectValue(*obj); if (!Invoke(cx, ag)) return false; if (Behavior::shouldExit(ag.rval(), args.rval())) return true; } /* Step d. */ k++; } /* Step 8. */ args.rval().set(Behavior::lateExitValue()); return true; } /* ES5 15.4.4.16. */ static JSBool array_every(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); return array_readonlyCommon(cx, args); } /* ES5 15.4.4.17. */ static JSBool array_some(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); return array_readonlyCommon(cx, args); } /* ES5 15.4.4.18. */ static JSBool array_forEach(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); return array_readonlyCommon(cx, args); } /* ES5 15.4.4.19. */ static JSBool array_map(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); /* Step 1. */ RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; /* Step 2-3. */ uint32_t len; if (!GetLengthProperty(cx, obj, &len)) return false; /* Step 4. */ if (args.length() == 0) { js_ReportMissingArg(cx, args.calleev(), 0); return false; } RootedObject callable(cx, ValueToCallable(cx, &args[0])); if (!callable) return false; /* Step 5. */ Value thisv = args.length() >= 2 ? args[1] : UndefinedValue(); /* Step 6. */ RootedObject arr(cx, NewDenseAllocatedArray(cx, len)); if (!arr) return false; TypeObject *newtype = GetTypeCallerInitObject(cx, JSProto_Array); if (!newtype) return false; arr->setType(newtype); /* Step 7. */ uint32_t k = 0; /* Step 8. */ RootedValue kValue(cx); InvokeArgsGuard ag; while (k < len) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; /* Step a, b, and c.i. */ JSBool kNotPresent; if (!GetElement(cx, obj, k, &kNotPresent, &kValue)) return false; /* Step c.ii-iii. */ if (!kNotPresent) { if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 3, &ag)) return false; ag.setCallee(ObjectValue(*callable)); ag.setThis(thisv); ag[0] = kValue; ag[1] = NumberValue(k); ag[2] = ObjectValue(*obj); if (!Invoke(cx, ag)) return false; kValue = ag.rval(); if (!SetArrayElement(cx, arr, k, kValue)) return false; } /* Step d. */ k++; } /* Step 9. */ args.rval().setObject(*arr); return true; } /* ES5 15.4.4.20. */ static JSBool array_filter(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); /* Step 1. */ RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; /* Step 2-3. */ uint32_t len; if (!GetLengthProperty(cx, obj, &len)) return false; /* Step 4. */ if (args.length() == 0) { js_ReportMissingArg(cx, args.calleev(), 0); return false; } RootedObject callable(cx, ValueToCallable(cx, &args[0])); if (!callable) return false; /* Step 5. */ Value thisv = args.length() >= 2 ? args[1] : UndefinedValue(); /* Step 6. */ RootedObject arr(cx, NewDenseAllocatedArray(cx, 0)); if (!arr) return false; TypeObject *newtype = GetTypeCallerInitObject(cx, JSProto_Array); if (!newtype) return false; arr->setType(newtype); /* Step 7. */ uint32_t k = 0; /* Step 8. */ uint32_t to = 0; /* Step 9. */ InvokeArgsGuard ag; RootedValue kValue(cx); while (k < len) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; /* Step a, b, and c.i. */ JSBool kNotPresent; if (!GetElement(cx, obj, k, &kNotPresent, &kValue)) return false; /* Step c.ii-iii. */ if (!kNotPresent) { if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 3, &ag)) return false; ag.setCallee(ObjectValue(*callable)); ag.setThis(thisv); ag[0] = kValue; ag[1] = NumberValue(k); ag[2] = ObjectValue(*obj); if (!Invoke(cx, ag)) return false; if (ToBoolean(ag.rval())) { if(!SetArrayElement(cx, arr, to, kValue)) return false; to++; } } /* Step d. */ k++; } /* Step 10. */ args.rval().setObject(*arr); return true; } /* ES5 15.4.4.21-15.4.4.22. */ class ArrayReduceBehavior { public: static void initialize(uint32_t len, uint32_t *start, uint32_t *end, int32_t *step) { *start = 0; *step = 1; *end = len; } }; class ArrayReduceRightBehavior { public: static void initialize(uint32_t len, uint32_t *start, uint32_t *end, int32_t *step) { *start = len - 1; *step = -1; /* * We rely on (well defined) unsigned integer underflow to check our * end condition after visiting the full range (including 0). */ *end = UINT32_MAX; } }; template static inline bool array_reduceCommon(JSContext *cx, CallArgs &args) { /* Step 1. */ RootedObject obj(cx, ToObject(cx, args.thisv())); if (!obj) return false; /* Step 2-3. */ uint32_t len; if (!GetLengthProperty(cx, obj, &len)) return false; /* Step 4. */ if (args.length() == 0) { js_ReportMissingArg(cx, args.calleev(), 0); return false; } RootedObject callable(cx, ValueToCallable(cx, &args[0])); if (!callable) return false; /* Step 5. */ if (len == 0 && args.length() < 2) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_EMPTY_ARRAY_REDUCE); return false; } /* Step 6. */ uint32_t k, end; int32_t step; Behavior::initialize(len, &k, &end, &step); /* Step 7-8. */ RootedValue accumulator(cx); if (args.length() >= 2) { accumulator = args[1]; } else { JSBool kNotPresent = true; while (kNotPresent && k != end) { if (!GetElement(cx, obj, k, &kNotPresent, &accumulator)) return false; k += step; } if (kNotPresent) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_EMPTY_ARRAY_REDUCE); return false; } } /* Step 9. */ RootedValue kValue(cx); InvokeArgsGuard ag; while (k != end) { if (!JS_CHECK_OPERATION_LIMIT(cx)) return false; /* Step a, b, and c.i. */ JSBool kNotPresent; if (!GetElement(cx, obj, k, &kNotPresent, &kValue)) return false; /* Step c.ii. */ if (!kNotPresent) { if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 4, &ag)) return false; ag.setCallee(ObjectValue(*callable)); ag.setThis(UndefinedValue()); ag[0] = accumulator; ag[1] = kValue; ag[2] = NumberValue(k); ag[3] = ObjectValue(*obj); if (!Invoke(cx, ag)) return false; accumulator = ag.rval(); } /* Step d. */ k += step; } /* Step 10. */ args.rval().set(accumulator); return true; } /* ES5 15.4.4.21. */ static JSBool array_reduce(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); return array_reduceCommon(cx, args); } /* ES5 15.4.4.22. */ static JSBool array_reduceRight(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); return array_reduceCommon(cx, args); } static JSBool array_isArray(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); bool isArray = args.length() > 0 && IsObjectWithClass(args[0], ESClass_Array, cx); args.rval().setBoolean(isArray); return true; } #define GENERIC JSFUN_GENERIC_NATIVE static JSFunctionSpec array_methods[] = { #if JS_HAS_TOSOURCE JS_FN(js_toSource_str, array_toSource, 0,0), #endif JS_FN(js_toString_str, array_toString, 0,0), JS_FN(js_toLocaleString_str,array_toLocaleString,0,0), /* Perl-ish methods. */ JS_FN("join", array_join, 1,JSFUN_GENERIC_NATIVE), JS_FN("reverse", array_reverse, 0,JSFUN_GENERIC_NATIVE), JS_FN("sort", array_sort, 1,JSFUN_GENERIC_NATIVE), JS_FN("push", array_push, 1,JSFUN_GENERIC_NATIVE), JS_FN("pop", array_pop, 0,JSFUN_GENERIC_NATIVE), JS_FN("shift", array_shift, 0,JSFUN_GENERIC_NATIVE), JS_FN("unshift", array_unshift, 1,JSFUN_GENERIC_NATIVE), JS_FN("splice", array_splice, 2,JSFUN_GENERIC_NATIVE), /* Pythonic sequence methods. */ JS_FN("concat", array_concat, 1,JSFUN_GENERIC_NATIVE), JS_FN("slice", array_slice, 2,JSFUN_GENERIC_NATIVE), JS_FN("indexOf", array_indexOf, 1,JSFUN_GENERIC_NATIVE), JS_FN("lastIndexOf", array_lastIndexOf, 1,JSFUN_GENERIC_NATIVE), JS_FN("forEach", array_forEach, 1,JSFUN_GENERIC_NATIVE), JS_FN("map", array_map, 1,JSFUN_GENERIC_NATIVE), JS_FN("reduce", array_reduce, 1,JSFUN_GENERIC_NATIVE), JS_FN("reduceRight", array_reduceRight, 1,JSFUN_GENERIC_NATIVE), JS_FN("filter", array_filter, 1,JSFUN_GENERIC_NATIVE), JS_FN("some", array_some, 1,JSFUN_GENERIC_NATIVE), JS_FN("every", array_every, 1,JSFUN_GENERIC_NATIVE), JS_FN("iterator", JS_ArrayIterator, 0,0), JS_FS_END }; static JSFunctionSpec array_static_methods[] = { JS_FN("isArray", array_isArray, 1,0), JS_FS_END }; /* ES5 15.4.2 */ JSBool js_Array(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); RootedTypeObject type(cx, GetTypeCallerInitObject(cx, JSProto_Array)); if (!type) return JS_FALSE; if (args.length() != 1 || !args[0].isNumber()) { if (!InitArrayTypes(cx, type, args.array(), args.length())) return false; JSObject *obj = (args.length() == 0) ? NewDenseEmptyArray(cx) : NewDenseCopiedArray(cx, args.length(), args.array()); if (!obj) return false; obj->setType(type); args.rval().setObject(*obj); return true; } uint32_t length; if (args[0].isInt32()) { int32_t i = args[0].toInt32(); if (i < 0) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_BAD_ARRAY_LENGTH); return false; } length = uint32_t(i); } else { double d = args[0].toDouble(); length = ToUint32(d); if (d != double(length)) { JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL, JSMSG_BAD_ARRAY_LENGTH); return false; } } RootedObject obj(cx, NewDenseUnallocatedArray(cx, length)); if (!obj) return false; obj->setType(type); /* If the length calculation overflowed, make sure that is marked for the new type. */ if (obj->getArrayLength() > INT32_MAX) JSObject::setArrayLength(cx, obj, obj->getArrayLength()); args.rval().setObject(*obj); return true; } JSObject * js_InitArrayClass(JSContext *cx, HandleObject obj) { JS_ASSERT(obj->isNative()); Rooted global(cx, &obj->asGlobal()); RootedObject arrayProto(cx, global->createBlankPrototype(cx, &SlowArrayClass)); if (!arrayProto || !AddLengthProperty(cx, arrayProto)) return NULL; JSObject::setArrayLength(cx, arrayProto, 0); RootedFunction ctor(cx); ctor = global->createConstructor(cx, js_Array, cx->names().Array, 1); if (!ctor) return NULL; /* * The default 'new' type of Array.prototype is required by type inference * to have unknown properties, to simplify handling of e.g. heterogenous * arrays in JSON and script literals and allows setDenseArrayElement to * be used without updating the indexed type set for such default arrays. */ if (!arrayProto->setNewTypeUnknown(cx)) return NULL; if (!LinkConstructorAndPrototype(cx, ctor, arrayProto)) return NULL; if (!DefinePropertiesAndBrand(cx, arrayProto, NULL, array_methods) || !DefinePropertiesAndBrand(cx, ctor, NULL, array_static_methods)) { return NULL; } if (!DefineConstructorAndPrototype(cx, global, JSProto_Array, ctor, arrayProto)) return NULL; return arrayProto; } /* * Array allocation functions. */ namespace js { static inline bool EnsureNewArrayElements(JSContext *cx, JSObject *obj, uint32_t length) { /* * If ensureElements creates dynamically allocated slots, then having * fixedSlots is a waste. */ DebugOnly cap = obj->getDenseArrayCapacity(); if (!obj->ensureElements(cx, length)) return false; JS_ASSERT_IF(cap, !obj->hasDynamicElements()); return true; } template static JS_ALWAYS_INLINE JSObject * NewArray(JSContext *cx, uint32_t length, RawObject protoArg) { gc::AllocKind kind = GuessArrayGCKind(length); JS_ASSERT(CanBeFinalizedInBackground(kind, &ArrayClass)); kind = GetBackgroundAllocKind(kind); NewObjectCache &cache = cx->runtime->newObjectCache; NewObjectCache::EntryIndex entry = -1; if (cache.lookupGlobal(&ArrayClass, cx->global(), kind, &entry)) { RootedObject obj(cx, cache.newObjectFromHit(cx, entry)); if (obj) { /* Fixup the elements pointer and length, which may be incorrect. */ obj->setFixedElements(); JSObject::setArrayLength(cx, obj, length); if (allocateCapacity && !EnsureNewArrayElements(cx, obj, length)) return NULL; return obj; } } RootedObject proto(cx, protoArg); if (protoArg) PoisonPtr(&protoArg); if (!proto && !FindProto(cx, &ArrayClass, &proto)) return NULL; RootedTypeObject type(cx, proto->getNewType(cx)); if (!type) return NULL; /* * Get a shape with zero fixed slots, regardless of the size class. * See JSObject::createDenseArray. */ RootedShape shape(cx, EmptyShape::getInitialShape(cx, &ArrayClass, TaggedProto(proto), cx->global(), gc::FINALIZE_OBJECT0)); if (!shape) return NULL; JSObject* obj = JSObject::createDenseArray(cx, kind, shape, type, length); if (!obj) return NULL; if (entry != -1) cache.fillGlobal(entry, &ArrayClass, cx->global(), kind, obj); if (allocateCapacity && !EnsureNewArrayElements(cx, obj, length)) return NULL; Probes::createObject(cx, obj); return obj; } JSObject * JS_FASTCALL NewDenseEmptyArray(JSContext *cx, RawObject proto /* = NULL */) { return NewArray(cx, 0, proto); } JSObject * JS_FASTCALL NewDenseAllocatedArray(JSContext *cx, uint32_t length, RawObject proto /* = NULL */) { return NewArray(cx, length, proto); } JSObject * JS_FASTCALL NewDenseUnallocatedArray(JSContext *cx, uint32_t length, RawObject proto /* = NULL */) { return NewArray(cx, length, proto); } #ifdef JS_METHODJIT JSObject * JS_FASTCALL mjit::stubs::NewDenseUnallocatedArray(VMFrame &f, uint32_t length) { JSObject *obj = NewArray(f.cx, length, (RawObject)f.scratch); if (!obj) THROWV(NULL); return obj; } #endif JSObject * NewDenseCopiedArray(JSContext *cx, uint32_t length, const Value *vp, RawObject proto /* = NULL */) { // XXX vp may be an internal pointer to an object's dense array elements. SkipRoot skip(cx, &vp); JSObject* obj = NewArray(cx, length, proto); if (!obj) return NULL; JS_ASSERT(obj->getDenseArrayCapacity() >= length); obj->setDenseArrayInitializedLength(vp ? length : 0); if (vp) obj->initDenseArrayElements(0, vp, length); return obj; } JSObject * NewSlowEmptyArray(JSContext *cx) { RootedObject obj(cx, NewBuiltinClassInstance(cx, &SlowArrayClass)); if (!obj || !AddLengthProperty(cx, obj)) return NULL; JSObject::setArrayLength(cx, obj, 0); return obj; } } // namespace js #ifdef DEBUG JSBool js_ArrayInfo(JSContext *cx, unsigned argc, Value *vp) { CallArgs args = CallArgsFromVp(argc, vp); JSObject *array; for (unsigned i = 0; i < args.length(); i++) { RootedValue arg(cx, args[i]); char *bytes = DecompileValueGenerator(cx, JSDVG_SEARCH_STACK, arg, NullPtr()); if (!bytes) return JS_FALSE; if (arg.isPrimitive() || !(array = arg.toObjectOrNull())->isArray()) { fprintf(stderr, "%s: not array\n", bytes); js_free(bytes); continue; } fprintf(stderr, "%s: %s (len %u", bytes, array->isDenseArray() ? "dense" : "sparse", array->getArrayLength()); if (array->isDenseArray()) { fprintf(stderr, ", capacity %u", array->getDenseArrayCapacity()); } fputs(")\n", stderr); js_free(bytes); } args.rval().setUndefined(); return true; } #endif