Method gc

express/Executor.cpp:84–89

}

void Executor::gc(GCFlag flag) {
    int level = flag == FULL ? 100 : 0;
    for (auto& iter : mRuntimeInfo.first) {
        iter.second->onGabageCollect(level);
    }
}

Executor::Executor(std::shared_ptr<Runtime> runtime, MNNForwardType type, int numberThread) {
    mRuntimeInfo.first.insert(std::make_pair(type, runtime));