Method exec_enter

src/core/impl/graph/var_node_mem_mgr.cpp:37–40

        : m_allocator{std::make_shared<DeviceMemoryAllocator>()} {}

void StaticDeviceMemoryManager::exec_enter() {
    auto flag = m_in_exec.test_and_set();
    mgb_assert(!flag, "double-lock on StaticDeviceMemoryManager");
}

void StaticDeviceMemoryManager::exec_exit() {
    mgb_assert(m_in_exec.test_and_set());