diff options
Diffstat (limited to 'Source/JavaScriptCore/runtime/JSString.cpp')
| -rw-r--r-- | Source/JavaScriptCore/runtime/JSString.cpp | 378 |
1 files changed, 248 insertions, 130 deletions
diff --git a/Source/JavaScriptCore/runtime/JSString.cpp b/Source/JavaScriptCore/runtime/JSString.cpp index 6f0b09d13..ad8a67a45 100644 --- a/Source/JavaScriptCore/runtime/JSString.cpp +++ b/Source/JavaScriptCore/runtime/JSString.cpp @@ -1,7 +1,7 @@ /* * Copyright (C) 1999-2002 Harri Porten (porten@kde.org) * Copyright (C) 2001 Peter Kelly (pmk@post.com) - * Copyright (C) 2004, 2007, 2008 Apple Inc. All rights reserved. + * Copyright (C) 2004, 2007, 2008, 2015 Apple Inc. All rights reserved. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public @@ -26,15 +26,19 @@ #include "JSGlobalObject.h" #include "JSGlobalObjectFunctions.h" #include "JSObject.h" -#include "Operations.h" +#include "JSCInlines.h" #include "StringObject.h" #include "StringPrototype.h" +#include "StrongInlines.h" namespace JSC { -static const unsigned substringFromRopeCutoff = 4; +const ClassInfo JSString::s_info = { "string", 0, 0, CREATE_METHOD_TABLE(JSString) }; -const ClassInfo JSString::s_info = { "string", 0, 0, 0, CREATE_METHOD_TABLE(JSString) }; +Structure* JSString::createStructure(VM& vm, JSGlobalObject* globalObject, JSValue proto) +{ + return Structure::create(vm, globalObject, proto, TypeInfo(StringType, StructureFlags), info()); +} void JSRopeString::RopeBuilder::expand() { @@ -52,93 +56,226 @@ void JSString::destroy(JSCell* cell) thisObject->JSString::~JSString(); } -void JSString::visitChildren(JSCell* cell, SlotVisitor& visitor) +void JSString::dumpToStream(const JSCell* cell, PrintStream& out) { - JSString* thisObject = jsCast<JSString*>(cell); - Base::visitChildren(thisObject, visitor); - - MARK_LOG_MESSAGE1("[%u]: ", thisObject->length()); - -#if ENABLE(OBJECT_MARK_LOGGING) - if (!thisObject->isRope()) { + const JSString* thisObject = jsCast<const JSString*>(cell); + out.printf("<%p, %s, [%u], ", thisObject, thisObject->className(), thisObject->length()); + if (thisObject->isRope()) + out.printf("[rope]"); + else { WTF::StringImpl* ourImpl = thisObject->m_value.impl(); if (ourImpl->is8Bit()) - MARK_LOG_MESSAGE1("[8 %p]", ourImpl->characters8()); + out.printf("[8 %p]", ourImpl->characters8()); else - MARK_LOG_MESSAGE1("[16 %p]", ourImpl->characters16()); - } else - MARK_LOG_MESSAGE0("[rope]: "); -#endif + out.printf("[16 %p]", ourImpl->characters16()); + } + out.printf(">"); +} +size_t JSString::estimatedSize(JSCell* cell) +{ + JSString* thisObject = jsCast<JSString*>(cell); + if (thisObject->isRope()) + return Base::estimatedSize(cell); + return Base::estimatedSize(cell) + thisObject->m_value.impl()->costDuringGC(); +} + +void JSString::visitChildren(JSCell* cell, SlotVisitor& visitor) +{ + JSString* thisObject = jsCast<JSString*>(cell); + Base::visitChildren(thisObject, visitor); + if (thisObject->isRope()) static_cast<JSRopeString*>(thisObject)->visitFibers(visitor); + else { + StringImpl* impl = thisObject->m_value.impl(); + ASSERT(impl); + visitor.reportExtraMemoryVisited(impl->costDuringGC()); + } } void JSRopeString::visitFibers(SlotVisitor& visitor) { - for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) - visitor.append(&m_fibers[i]); + if (isSubstring()) { + visitor.append(&substringBase()); + return; + } + for (size_t i = 0; i < s_maxInternalRopeLength && fiber(i); ++i) + visitor.append(&fiber(i)); +} + +static const unsigned maxLengthForOnStackResolve = 2048; + +void JSRopeString::resolveRopeInternal8(LChar* buffer) const +{ + if (isSubstring()) { + StringImpl::copyChars( + buffer, substringBase()->m_value.characters8() + substringOffset(), m_length); + return; + } + + resolveRopeInternal8NoSubstring(buffer); +} + +void JSRopeString::resolveRopeInternal8NoSubstring(LChar* buffer) const +{ + for (size_t i = 0; i < s_maxInternalRopeLength && fiber(i); ++i) { + if (fiber(i)->isRope()) { + resolveRopeSlowCase8(buffer); + return; + } + } + + LChar* position = buffer; + for (size_t i = 0; i < s_maxInternalRopeLength && fiber(i); ++i) { + const StringImpl& fiberString = *fiber(i)->m_value.impl(); + unsigned length = fiberString.length(); + StringImpl::copyChars(position, fiberString.characters8(), length); + position += length; + } + ASSERT((buffer + m_length) == position); +} + +void JSRopeString::resolveRopeInternal16(UChar* buffer) const +{ + if (isSubstring()) { + StringImpl::copyChars( + buffer, substringBase()->m_value.characters16() + substringOffset(), m_length); + return; + } + + resolveRopeInternal16NoSubstring(buffer); +} + +void JSRopeString::resolveRopeInternal16NoSubstring(UChar* buffer) const +{ + for (size_t i = 0; i < s_maxInternalRopeLength && fiber(i); ++i) { + if (fiber(i)->isRope()) { + resolveRopeSlowCase(buffer); + return; + } + } + + UChar* position = buffer; + for (size_t i = 0; i < s_maxInternalRopeLength && fiber(i); ++i) { + const StringImpl& fiberString = *fiber(i)->m_value.impl(); + unsigned length = fiberString.length(); + if (fiberString.is8Bit()) + StringImpl::copyChars(position, fiberString.characters8(), length); + else + StringImpl::copyChars(position, fiberString.characters16(), length); + position += length; + } + ASSERT((buffer + m_length) == position); +} + +void JSRopeString::resolveRopeToAtomicString(ExecState* exec) const +{ + if (m_length > maxLengthForOnStackResolve) { + resolveRope(exec); + m_value = AtomicString(m_value); + setIs8Bit(m_value.impl()->is8Bit()); + return; + } + + if (is8Bit()) { + LChar buffer[maxLengthForOnStackResolve]; + resolveRopeInternal8(buffer); + m_value = AtomicString(buffer, m_length); + setIs8Bit(m_value.impl()->is8Bit()); + } else { + UChar buffer[maxLengthForOnStackResolve]; + resolveRopeInternal16(buffer); + m_value = AtomicString(buffer, m_length); + setIs8Bit(m_value.impl()->is8Bit()); + } + + clearFibers(); + + // If we resolved a string that didn't previously exist, notify the heap that we've grown. + if (m_value.impl()->hasOneRef()) + Heap::heap(this)->reportExtraMemoryAllocated(m_value.impl()->cost()); +} + +void JSRopeString::clearFibers() const +{ + for (size_t i = 0; i < s_maxInternalRopeLength; ++i) + u[i].number = 0; +} + +RefPtr<AtomicStringImpl> JSRopeString::resolveRopeToExistingAtomicString(ExecState* exec) const +{ + if (m_length > maxLengthForOnStackResolve) { + resolveRope(exec); + if (RefPtr<AtomicStringImpl> existingAtomicString = AtomicStringImpl::lookUp(m_value.impl())) { + m_value = *existingAtomicString; + setIs8Bit(m_value.impl()->is8Bit()); + clearFibers(); + return existingAtomicString; + } + return nullptr; + } + + if (is8Bit()) { + LChar buffer[maxLengthForOnStackResolve]; + resolveRopeInternal8(buffer); + if (RefPtr<AtomicStringImpl> existingAtomicString = AtomicStringImpl::lookUp(buffer, m_length)) { + m_value = *existingAtomicString; + setIs8Bit(m_value.impl()->is8Bit()); + clearFibers(); + return existingAtomicString; + } + } else { + UChar buffer[maxLengthForOnStackResolve]; + resolveRopeInternal16(buffer); + if (RefPtr<AtomicStringImpl> existingAtomicString = AtomicStringImpl::lookUp(buffer, m_length)) { + m_value = *existingAtomicString; + setIs8Bit(m_value.impl()->is8Bit()); + clearFibers(); + return existingAtomicString; + } + } + + return nullptr; } void JSRopeString::resolveRope(ExecState* exec) const { ASSERT(isRope()); - + + if (isSubstring()) { + ASSERT(!substringBase()->isRope()); + m_value = substringBase()->m_value.substringSharingImpl(substringOffset(), m_length); + substringBase().clear(); + return; + } + if (is8Bit()) { LChar* buffer; if (RefPtr<StringImpl> newImpl = StringImpl::tryCreateUninitialized(m_length, buffer)) { - Heap::heap(this)->reportExtraMemoryCost(newImpl->cost()); + Heap::heap(this)->reportExtraMemoryAllocated(newImpl->cost()); m_value = newImpl.release(); } else { outOfMemory(exec); return; } - - for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { - if (m_fibers[i]->isRope()) - return resolveRopeSlowCase8(buffer); - } - - LChar* position = buffer; - for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { - StringImpl* string = m_fibers[i]->m_value.impl(); - unsigned length = string->length(); - StringImpl::copyChars(position, string->characters8(), length); - position += length; - m_fibers[i].clear(); - } - ASSERT((buffer + m_length) == position); + resolveRopeInternal8NoSubstring(buffer); + clearFibers(); ASSERT(!isRope()); - return; } UChar* buffer; if (RefPtr<StringImpl> newImpl = StringImpl::tryCreateUninitialized(m_length, buffer)) { - Heap::heap(this)->reportExtraMemoryCost(newImpl->cost()); + Heap::heap(this)->reportExtraMemoryAllocated(newImpl->cost()); m_value = newImpl.release(); } else { outOfMemory(exec); return; } - for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { - if (m_fibers[i]->isRope()) - return resolveRopeSlowCase(buffer); - } - - UChar* position = buffer; - for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { - StringImpl* string = m_fibers[i]->m_value.impl(); - unsigned length = string->length(); - if (string->is8Bit()) - StringImpl::copyChars(position, string->characters8(), length); - else - StringImpl::copyChars(position, string->characters16(), length); - position += length; - m_fibers[i].clear(); - } - ASSERT((buffer + m_length) == position); + resolveRopeInternal16NoSubstring(buffer); + clearFibers(); ASSERT(!isRope()); } @@ -157,31 +294,35 @@ void JSRopeString::resolveRopeSlowCase8(LChar* buffer) const LChar* position = buffer + m_length; // We will be working backwards over the rope. Vector<JSString*, 32, UnsafeVectorOverflow> workQueue; // Putting strings into a Vector is only OK because there are no GC points in this method. - for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) { - workQueue.append(m_fibers[i].get()); - // Clearing here works only because there are no GC points in this method. - m_fibers[i].clear(); - } + for (size_t i = 0; i < s_maxInternalRopeLength && fiber(i); ++i) + workQueue.append(fiber(i).get()); while (!workQueue.isEmpty()) { JSString* currentFiber = workQueue.last(); workQueue.removeLast(); + const LChar* characters; + if (currentFiber->isRope()) { JSRopeString* currentFiberAsRope = static_cast<JSRopeString*>(currentFiber); - for (size_t i = 0; i < s_maxInternalRopeLength && currentFiberAsRope->m_fibers[i]; ++i) - workQueue.append(currentFiberAsRope->m_fibers[i].get()); - continue; - } - - StringImpl* string = static_cast<StringImpl*>(currentFiber->m_value.impl()); - unsigned length = string->length(); + if (!currentFiberAsRope->isSubstring()) { + for (size_t i = 0; i < s_maxInternalRopeLength && currentFiberAsRope->fiber(i); ++i) + workQueue.append(currentFiberAsRope->fiber(i).get()); + continue; + } + ASSERT(!currentFiberAsRope->substringBase()->isRope()); + characters = + currentFiberAsRope->substringBase()->m_value.characters8() + + currentFiberAsRope->substringOffset(); + } else + characters = currentFiber->m_value.characters8(); + + unsigned length = currentFiber->length(); position -= length; - StringImpl::copyChars(position, string->characters8(), length); + StringImpl::copyChars(position, characters, length); } ASSERT(buffer == position); - ASSERT(!isRope()); } void JSRopeString::resolveRopeSlowCase(UChar* buffer) const @@ -189,8 +330,8 @@ void JSRopeString::resolveRopeSlowCase(UChar* buffer) const UChar* position = buffer + m_length; // We will be working backwards over the rope. Vector<JSString*, 32, UnsafeVectorOverflow> workQueue; // These strings are kept alive by the parent rope, so using a Vector is OK. - for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) - workQueue.append(m_fibers[i].get()); + for (size_t i = 0; i < s_maxInternalRopeLength && fiber(i); ++i) + workQueue.append(fiber(i).get()); while (!workQueue.isEmpty()) { JSString* currentFiber = workQueue.last(); @@ -198,8 +339,21 @@ void JSRopeString::resolveRopeSlowCase(UChar* buffer) const if (currentFiber->isRope()) { JSRopeString* currentFiberAsRope = static_cast<JSRopeString*>(currentFiber); - for (size_t i = 0; i < s_maxInternalRopeLength && currentFiberAsRope->m_fibers[i]; ++i) - workQueue.append(currentFiberAsRope->m_fibers[i].get()); + if (currentFiberAsRope->isSubstring()) { + ASSERT(!currentFiberAsRope->substringBase()->isRope()); + StringImpl* string = static_cast<StringImpl*>( + currentFiberAsRope->substringBase()->m_value.impl()); + unsigned offset = currentFiberAsRope->substringOffset(); + unsigned length = currentFiberAsRope->length(); + position -= length; + if (string->is8Bit()) + StringImpl::copyChars(position, string->characters8() + offset, length); + else + StringImpl::copyChars(position, string->characters16() + offset, length); + continue; + } + for (size_t i = 0; i < s_maxInternalRopeLength && currentFiberAsRope->fiber(i); ++i) + workQueue.append(currentFiberAsRope->fiber(i).get()); continue; } @@ -213,31 +367,17 @@ void JSRopeString::resolveRopeSlowCase(UChar* buffer) const } ASSERT(buffer == position); - ASSERT(!isRope()); } void JSRopeString::outOfMemory(ExecState* exec) const { - for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) - m_fibers[i].clear(); + clearFibers(); ASSERT(isRope()); ASSERT(m_value.isNull()); if (exec) throwOutOfMemoryError(exec); } -JSString* JSRopeString::getIndexSlowCase(ExecState* exec, unsigned i) -{ - ASSERT(isRope()); - resolveRope(exec); - // Return a safe no-value result, this should never be used, since the excetion will be thrown. - if (exec->exception()) - return jsEmptyString(exec); - ASSERT(!isRope()); - RELEASE_ASSERT(i < m_value.length()); - return jsSingleCharacterSubstring(exec, m_value, i); -} - JSValue JSString::toPrimitive(ExecState*, PreferredPrimitiveType) const { return const_cast<JSString*>(this); @@ -246,53 +386,32 @@ JSValue JSString::toPrimitive(ExecState*, PreferredPrimitiveType) const bool JSString::getPrimitiveNumber(ExecState* exec, double& number, JSValue& result) const { result = this; - number = jsToNumber(value(exec)); + number = jsToNumber(unsafeView(*exec)); return false; } -bool JSString::toBoolean() const -{ - return m_length; -} - double JSString::toNumber(ExecState* exec) const { - return jsToNumber(value(exec)); + return jsToNumber(unsafeView(*exec)); } -inline StringObject* StringObject::create(ExecState* exec, JSGlobalObject* globalObject, JSString* string) +inline StringObject* StringObject::create(VM& vm, JSGlobalObject* globalObject, JSString* string) { - StringObject* object = new (NotNull, allocateCell<StringObject>(*exec->heap())) StringObject(exec->vm(), globalObject->stringObjectStructure()); - object->finishCreation(exec->vm(), string); + StringObject* object = new (NotNull, allocateCell<StringObject>(vm.heap)) StringObject(vm, globalObject->stringObjectStructure()); + object->finishCreation(vm, string); return object; } JSObject* JSString::toObject(ExecState* exec, JSGlobalObject* globalObject) const { - return StringObject::create(exec, globalObject, const_cast<JSString*>(this)); -} - -JSObject* JSString::toThisObject(JSCell* cell, ExecState* exec) -{ - return StringObject::create(exec, exec->lexicalGlobalObject(), jsCast<JSString*>(cell)); + return StringObject::create(exec->vm(), globalObject, const_cast<JSString*>(this)); } -bool JSString::getOwnPropertySlot(JSCell* cell, ExecState* exec, PropertyName propertyName, PropertySlot& slot) +JSValue JSString::toThis(JSCell* cell, ExecState* exec, ECMAMode ecmaMode) { - JSString* thisObject = jsCast<JSString*>(cell); - // The semantics here are really getPropertySlot, not getOwnPropertySlot. - // This function should only be called by JSValue::get. - if (thisObject->getStringPropertySlot(exec, propertyName, slot)) - return true; - slot.setBase(thisObject); - JSObject* object; - for (JSValue prototype = exec->lexicalGlobalObject()->stringPrototype(); !prototype.isNull(); prototype = object->prototype()) { - object = asObject(prototype); - if (object->methodTable()->getOwnPropertySlot(object, exec, propertyName, slot)) - return true; - } - slot.setUndefined(); - return true; + if (ecmaMode == StrictMode) + return cell; + return StringObject::create(exec->vm(), exec->lexicalGlobalObject(), jsCast<JSString*>(cell)); } bool JSString::getStringPropertyDescriptor(ExecState* exec, PropertyName propertyName, PropertyDescriptor& descriptor) @@ -302,24 +421,23 @@ bool JSString::getStringPropertyDescriptor(ExecState* exec, PropertyName propert return true; } - unsigned i = propertyName.asIndex(); - if (i < m_length) { - ASSERT(i != PropertyName::NotAnIndex); // No need for an explicit check, the above test would always fail! - descriptor.setDescriptor(getIndex(exec, i), DontDelete | ReadOnly); + Optional<uint32_t> index = parseIndex(propertyName); + if (index && index.value() < m_length) { + descriptor.setDescriptor(getIndex(exec, index.value()), DontDelete | ReadOnly); return true; } return false; } -bool JSString::getOwnPropertySlotByIndex(JSCell* cell, ExecState* exec, unsigned propertyName, PropertySlot& slot) +JSString* jsStringWithCacheSlowCase(VM& vm, StringImpl& stringImpl) { - JSString* thisObject = jsCast<JSString*>(cell); - // The semantics here are really getPropertySlot, not getOwnPropertySlot. - // This function should only be called by JSValue::get. - if (thisObject->getStringPropertySlot(exec, propertyName, slot)) - return true; - return JSString::getOwnPropertySlot(thisObject, exec, Identifier::from(exec, propertyName), slot); + if (JSString* string = vm.stringCache.get(&stringImpl)) + return string; + + JSString* string = jsString(&vm, String(stringImpl)); + vm.lastCachedString.set(vm, string); + return string; } } // namespace JSC |