shared_ptr<const DiscreteBoundaryOperator<ResultType>>
DiscreteBoundaryOperatorCache<BasisFunctionType, ResultType>::getWeakForm(
const Context<BasisFunctionType, ResultType> &context,
const AbstractBoundaryOperator<BasisFunctionType, ResultType> &op) const {
// std::cout << "Weak form of operator of type " << typeid(op).name()
// << " requested from cache" << std::endl;
typedef DiscreteBoundaryOperator<ResultType> DiscreteOp;
shared_ptr<const AbstractBoundaryOperatorId> id = op.id();
if (!id) { // operator is not cacheable
// std::cout << "Noncacheable discrete operator requested" << std::endl;
return op.assembleWeakForm(context);
}
// Check if a weak pointer to discrete operator exists in cache
typename Impl::DiscreteBoundaryOperatorMap::const_iterator it =
m_impl->discreteOps.find(id);
if (it != m_impl->discreteOps.end()) {
// std::cout << "Weak pointer to discrete operator found in cache" <<
// std::endl;
// Check if the weak pointer still refers to an existing object
if (shared_ptr<const DiscreteOp> cachedDiscreteOp = it->second.lock()) {
// std::cout << "Weak pointer is valid" << std::endl;
return cachedDiscreteOp;
} else {
// std::cout << "Weak pointer is invalid, reconstructing discrete
// operator" << std::endl;
shared_ptr<const DiscreteOp> discreteOp = op.assembleWeakForm(context);
// TODO: THIS IS NOT NOT THREAD-SAFE!!!
it->second = discreteOp;
return it->second.lock();
}
}
// std::cout << "Discrete operator not found in cache -- constructing from
// scratch"
// << std::endl;
// Discrete operator not found in cache, construct it...
shared_ptr<const DiscreteOp> discreteOp = op.assembleWeakForm(context);
// and attempt to insert it into the map
std::pair<typename Impl::DiscreteBoundaryOperatorMap::iterator, bool> result =
m_impl->discreteOps.insert(std::make_pair(id, discreteOp));
// Return pointer to the discrete operator that ended up in the map.
return result.first->second.lock();
// (Note: if another thread was faster in trying to insert a discrete
// operator into the map, the operator we constructed (pointed by
// discreteOp) will be destructed now, as discreteOp goes out of scope.)
}
shared_ptr<const DiscreteBoundaryOperator<ResultType>>
Context<BasisFunctionType, ResultType>::getWeakForm(
const AbstractBoundaryOperator<BasisFunctionType, ResultType> &op) const {
return op.assembleWeakForm(*this);
}
