#include "JSString.h"
#include "JSGlobalObject.h"
+#include "JSGlobalObjectFunctions.h"
#include "JSObject.h"
+#include "JSCInlines.h"
#include "StringObject.h"
#include "StringPrototype.h"
+#include "StrongInlines.h"
namespace JSC {
+
+const ClassInfo JSString::s_info = { "string", 0, 0, 0, CREATE_METHOD_TABLE(JSString) };
-JSValue JSString::toPrimitive(ExecState*, PreferredPrimitiveType) const
+void JSRopeString::RopeBuilder::expand()
{
- return const_cast<JSString*>(this);
+ ASSERT(m_index == JSRopeString::s_maxInternalRopeLength);
+ JSString* jsString = m_jsString;
+ RELEASE_ASSERT(jsString);
+ m_jsString = jsStringBuilder(&m_vm);
+ m_index = 0;
+ append(jsString);
}
-bool JSString::getPrimitiveNumber(ExecState*, double& number, JSValue& value)
+void JSString::destroy(JSCell* cell)
{
- value = this;
- number = m_value.toDouble();
- return false;
+ JSString* thisObject = static_cast<JSString*>(cell);
+ thisObject->JSString::~JSString();
}
-bool JSString::toBoolean(ExecState*) const
+void JSString::dumpToStream(const JSCell* cell, PrintStream& out)
{
- return !m_value.isEmpty();
+ 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())
+ out.printf("[8 %p]", ourImpl->characters8());
+ else
+ out.printf("[16 %p]", ourImpl->characters16());
+ }
+ out.printf(">");
}
-double JSString::toNumber(ExecState*) const
+void JSString::visitChildren(JSCell* cell, SlotVisitor& visitor)
{
- return m_value.toDouble();
+ 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.reportExtraMemoryUsage(thisObject, impl->costDuringGC());
+ }
}
-UString JSString::toString(ExecState*) const
+void JSRopeString::visitFibers(SlotVisitor& visitor)
{
- return m_value;
+ for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i)
+ visitor.append(&m_fibers[i]);
}
-UString JSString::toThisString(ExecState*) const
+static const unsigned maxLengthForOnStackResolve = 2048;
+
+void JSRopeString::resolveRopeInternal8(LChar* buffer) const
{
- return m_value;
+ for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) {
+ if (m_fibers[i]->isRope()) {
+ resolveRopeSlowCase8(buffer);
+ return;
+ }
+ }
+
+ LChar* position = buffer;
+ for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) {
+ const StringImpl& fiberString = *m_fibers[i]->m_value.impl();
+ unsigned length = fiberString.length();
+ StringImpl::copyChars(position, fiberString.characters8(), length);
+ position += length;
+ }
+ ASSERT((buffer + m_length) == position);
}
-JSString* JSString::toThisJSString(ExecState*)
+void JSRopeString::resolveRopeInternal16(UChar* buffer) const
{
- return this;
+ for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) {
+ if (m_fibers[i]->isRope()) {
+ resolveRopeSlowCase(buffer);
+ return;
+ }
+ }
+
+ UChar* position = buffer;
+ for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i) {
+ const StringImpl& fiberString = *m_fibers[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);
}
-inline StringObject* StringObject::create(ExecState* exec, JSString* string)
+void JSRopeString::resolveRopeToAtomicString(ExecState* exec) const
{
- return new (exec) StringObject(exec->lexicalGlobalObject()->stringObjectStructure(), string);
+ if (m_length > maxLengthForOnStackResolve) {
+ resolveRope(exec);
+ m_value = AtomicString(m_value);
+ return;
+ }
+
+ if (is8Bit()) {
+ LChar buffer[maxLengthForOnStackResolve];
+ resolveRopeInternal8(buffer);
+ m_value = AtomicString(buffer, m_length);
+ } else {
+ UChar buffer[maxLengthForOnStackResolve];
+ resolveRopeInternal16(buffer);
+ m_value = AtomicString(buffer, m_length);
+ }
+
+ 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)->reportExtraMemoryCost(m_value.impl()->cost());
}
-JSObject* JSString::toObject(ExecState* exec) const
+void JSRopeString::clearFibers() const
{
- return StringObject::create(exec, const_cast<JSString*>(this));
+ for (size_t i = 0; i < s_maxInternalRopeLength && m_fibers[i]; ++i)
+ m_fibers[i].clear();
}
-JSObject* JSString::toThisObject(ExecState* exec) const
+AtomicStringImpl* JSRopeString::resolveRopeToExistingAtomicString(ExecState* exec) const
{
- return StringObject::create(exec, const_cast<JSString*>(this));
+ if (m_length > maxLengthForOnStackResolve) {
+ resolveRope(exec);
+ if (AtomicStringImpl* existingAtomicString = AtomicString::find(m_value.impl())) {
+ m_value = *existingAtomicString;
+ clearFibers();
+ return existingAtomicString;
+ }
+ return nullptr;
+ }
+
+ if (is8Bit()) {
+ LChar buffer[maxLengthForOnStackResolve];
+ resolveRopeInternal8(buffer);
+ if (AtomicStringImpl* existingAtomicString = AtomicString::find(buffer, m_length)) {
+ m_value = *existingAtomicString;
+ clearFibers();
+ return existingAtomicString;
+ }
+ } else {
+ UChar buffer[maxLengthForOnStackResolve];
+ resolveRopeInternal16(buffer);
+ if (AtomicStringImpl* existingAtomicString = AtomicString::find(buffer, m_length)) {
+ m_value = *existingAtomicString;
+ clearFibers();
+ return existingAtomicString;
+ }
+ }
+
+ return nullptr;
}
-bool JSString::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
+void JSRopeString::resolveRope(ExecState* exec) const
{
- // The semantics here are really getPropertySlot, not getOwnPropertySlot.
- // This function should only be called by JSValue::get.
- if (getStringPropertySlot(exec, propertyName, slot))
- return true;
- if (propertyName == exec->propertyNames().underscoreProto) {
- slot.setValue(exec->lexicalGlobalObject()->stringPrototype());
- return true;
+ ASSERT(isRope());
+
+ if (is8Bit()) {
+ LChar* buffer;
+ if (RefPtr<StringImpl> newImpl = StringImpl::tryCreateUninitialized(m_length, buffer)) {
+ Heap::heap(this)->reportExtraMemoryCost(newImpl->cost());
+ m_value = newImpl.release();
+ } else {
+ outOfMemory(exec);
+ return;
+ }
+ resolveRopeInternal8(buffer);
+ clearFibers();
+ ASSERT(!isRope());
+ return;
}
- slot.setBase(this);
- JSObject* object;
- for (JSValue prototype = exec->lexicalGlobalObject()->stringPrototype(); !prototype.isNull(); prototype = object->prototype()) {
- object = asObject(prototype);
- if (object->getOwnPropertySlot(exec, propertyName, slot))
- return true;
+
+ UChar* buffer;
+ if (RefPtr<StringImpl> newImpl = StringImpl::tryCreateUninitialized(m_length, buffer)) {
+ Heap::heap(this)->reportExtraMemoryCost(newImpl->cost());
+ m_value = newImpl.release();
+ } else {
+ outOfMemory(exec);
+ return;
}
- slot.setUndefined();
- return true;
+
+ resolveRopeInternal16(buffer);
+ clearFibers();
+ ASSERT(!isRope());
}
-bool JSString::getOwnPropertySlot(ExecState* exec, unsigned propertyName, PropertySlot& slot)
+// Overview: These functions convert a JSString from holding a string in rope form
+// down to a simple String representation. It does so by building up the string
+// backwards, since we want to avoid recursion, we expect that the tree structure
+// representing the rope is likely imbalanced with more nodes down the left side
+// (since appending to the string is likely more common) - and as such resolving
+// in this fashion should minimize work queue size. (If we built the queue forwards
+// we would likely have to place all of the constituent StringImpls into the
+// Vector before performing any concatenation, but by working backwards we likely
+// only fill the queue with the number of substrings at any given level in a
+// rope-of-ropes.)
+void JSRopeString::resolveRopeSlowCase8(LChar* buffer) const
{
- // The semantics here are really getPropertySlot, not getOwnPropertySlot.
- // This function should only be called by JSValue::get.
- if (getStringPropertySlot(exec, propertyName, slot))
- return true;
- return JSString::getOwnPropertySlot(exec, Identifier::from(exec, propertyName), slot);
+ 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());
+
+ while (!workQueue.isEmpty()) {
+ JSString* currentFiber = workQueue.last();
+ workQueue.removeLast();
+
+ 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();
+ position -= length;
+ StringImpl::copyChars(position, string->characters8(), length);
+ }
+
+ ASSERT(buffer == position);
}
-JSString* jsString(JSGlobalData* globalData, const UString& s)
+void JSRopeString::resolveRopeSlowCase(UChar* buffer) const
{
- int size = s.size();
- if (!size)
- return globalData->smallStrings.emptyString(globalData);
- if (size == 1) {
- UChar c = s.data()[0];
- if (c <= 0xFF)
- return globalData->smallStrings.singleCharacterString(globalData, c);
+ 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());
+
+ while (!workQueue.isEmpty()) {
+ JSString* currentFiber = workQueue.last();
+ workQueue.removeLast();
+
+ 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();
+ position -= length;
+ if (string->is8Bit())
+ StringImpl::copyChars(position, string->characters8(), length);
+ else
+ StringImpl::copyChars(position, string->characters16(), length);
}
- return new (globalData) JSString(globalData, s);
+
+ ASSERT(buffer == position);
}
-
-JSString* jsSubstring(JSGlobalData* globalData, const UString& s, unsigned offset, unsigned length)
+
+void JSRopeString::outOfMemory(ExecState* exec) const
{
- ASSERT(offset <= static_cast<unsigned>(s.size()));
- ASSERT(length <= static_cast<unsigned>(s.size()));
- ASSERT(offset + length <= static_cast<unsigned>(s.size()));
- if (!length)
- return globalData->smallStrings.emptyString(globalData);
- if (length == 1) {
- UChar c = s.data()[offset];
- if (c <= 0xFF)
- return globalData->smallStrings.singleCharacterString(globalData, c);
- }
- return new (globalData) JSString(globalData, UString::Rep::create(s.rep(), offset, length));
+ 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);
+}
+
+bool JSString::getPrimitiveNumber(ExecState* exec, double& number, JSValue& result) const
+{
+ result = this;
+ number = jsToNumber(value(exec));
+ return false;
}
-JSString* jsOwnedString(JSGlobalData* globalData, const UString& s)
+bool JSString::toBoolean() const
{
- int size = s.size();
- if (!size)
- return globalData->smallStrings.emptyString(globalData);
- if (size == 1) {
- UChar c = s.data()[0];
- if (c <= 0xFF)
- return globalData->smallStrings.singleCharacterString(globalData, c);
+ return m_length;
+}
+
+double JSString::toNumber(ExecState* exec) const
+{
+ return jsToNumber(value(exec));
+}
+
+inline StringObject* StringObject::create(VM& vm, JSGlobalObject* globalObject, JSString* 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->vm(), globalObject, const_cast<JSString*>(this));
+}
+
+JSValue JSString::toThis(JSCell* cell, ExecState* exec, ECMAMode ecmaMode)
+{
+ if (ecmaMode == StrictMode)
+ return cell;
+ return StringObject::create(exec->vm(), exec->lexicalGlobalObject(), jsCast<JSString*>(cell));
+}
+
+bool JSString::getStringPropertyDescriptor(ExecState* exec, PropertyName propertyName, PropertyDescriptor& descriptor)
+{
+ if (propertyName == exec->propertyNames().length) {
+ descriptor.setDescriptor(jsNumber(m_length), DontEnum | DontDelete | ReadOnly);
+ return true;
}
- return new (globalData) JSString(globalData, s, JSString::HasOtherOwner);
+
+ 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);
+ return true;
+ }
+
+ return false;
+}
+
+JSString* jsStringWithCacheSlowCase(VM& vm, StringImpl& stringImpl)
+{
+ auto addResult = vm.stringCache.add(&stringImpl, nullptr);
+ if (addResult.isNewEntry)
+ addResult.iterator->value = jsString(&vm, String(stringImpl));
+ vm.lastCachedString.set(vm, addResult.iterator->value.get());
+ return addResult.iterator->value.get();
}
} // namespace JSC
projects / apple / javascriptcore.git / blobdiff