void skip() {
Class* cls;
do {
cls = *m_next->second.clsList();
if (!cls || !cls->getCached()) ++m_next;
} while (!empty() && !cls);
}
Class* front() {
ASSERT(!empty());
Class* c = *m_next->second.clsList();
ASSERT(c);
c = c->getCached();
ASSERT(c);
return c;
}
Class* Unit::loadClass(const NamedEntity* ne,
const StringData* name) {
Class *cls = *ne->clsList();
if (LIKELY(cls != NULL)) {
cls = cls->getCached();
if (LIKELY(cls != NULL)) return cls;
}
VMRegAnchor _;
AutoloadHandler::s_instance->invokeHandler(name->data());
return Unit::lookupClass(ne);
}
Class* Unit::defClass(PreClass* preClass,
bool failIsFatal /* = true */) {
Class* const* clsList = preClass->namedEntity()->clsList();
Class* top = *clsList;
if (top) {
Class *cls = top->getCached();
if (cls) {
// Raise a fatal unless the existing class definition is identical to the
// one this invocation would create.
if (cls->preClass() != preClass) {
if (failIsFatal) {
raise_error("Class already declared: %s", preClass->name()->data());
}
return NULL;
}
return cls;
}
}
// Get a compatible Class, and add it to the list of defined classes.
Class* parent = NULL;
for (;;) {
// Search for a compatible extant class. Searching from most to least
// recently created may have better locality than alternative search orders.
// In addition, its the only simple way to make this work lock free...
for (Class* class_ = top; class_ != NULL; class_ = class_->m_nextClass) {
if (class_->preClass() != preClass) continue;
Class::Avail avail = class_->avail(parent, failIsFatal /*tryAutoload*/);
if (LIKELY(avail == Class::AvailTrue)) {
class_->setCached();
DEBUGGER_ATTACHED_ONLY(phpDefClassHook(class_));
return class_;
}
if (avail == Class::AvailFail) {
if (failIsFatal) {
raise_error("unknown class %s", parent->name()->data());
}
return NULL;
}
ASSERT(avail == Class::AvailFalse);
}
// Create a new class.
if (!parent && preClass->parent()->size() != 0) {
parent = Unit::getClass(preClass->parent(), failIsFatal);
if (parent == NULL) {
if (failIsFatal) {
raise_error("unknown class %s", preClass->parent()->data());
}
return NULL;
}
}
VMExecutionContext* ec = g_vmContext;
ActRec* fp = ec->getFP();
PC pc = ec->getPC();
bool needsFrame = ec->m_stack.top() &&
(!fp || fp->m_func->unit() != preClass->unit());
if (needsFrame) {
/*
we can be called from Unit::merge, which hasnt yet setup
the frame (because often it doesnt need to).
Set up a fake frame here, in case of errors.
But note that mergeUnit is called for systemlib etc before the
stack has been setup. So dont do anything if m_stack.top()
is NULL
*/
ActRec &tmp = *ec->m_stack.allocA();
tmp.m_savedRbp = (uint64_t)fp;
tmp.m_savedRip = 0;
tmp.m_func = preClass->unit()->getMain();
tmp.m_soff = preClass->getOffset() - tmp.m_func->base();
tmp.setThis(NULL);
tmp.m_varEnv = 0;
tmp.initNumArgs(0);
ec->m_fp = &tmp;
ec->m_pc = preClass->unit()->at(preClass->getOffset());
ec->pushLocalsAndIterators(tmp.m_func);
}
ClassPtr newClass(Class::newClass(preClass, parent));
if (needsFrame) {
ec->m_stack.top() = (Cell*)(ec->m_fp+1);
ec->m_fp = fp;
ec->m_pc = pc;
}
Lock l(Unit::s_classesMutex);
/*
We could re-enter via Unit::getClass() or class_->avail(), so
no need for *clsList to be volatile
*/
if (UNLIKELY(top != *clsList)) {
top = *clsList;
continue;
}
if (top) {
newClass->m_cachedOffset = top->m_cachedOffset;
} else {
newClass->m_cachedOffset =
Transl::TargetCache::allocKnownClass(preClass->name());
}
newClass->m_nextClass = top;
Util::compiler_membar();
*const_cast<Class**>(clsList) = newClass.get();
newClass.get()->incAtomicCount();
newClass.get()->setCached();
DEBUGGER_ATTACHED_ONLY(phpDefClassHook(newClass.get()));
return newClass.get();
}
}
