Method prefetch_context

thread/thread.cpp:642–653

            plock->foreground_unlock();
        }
        static void prefetch_context(thread* from, thread* to)
        {
#ifdef CONTEXT_PREFETCHING
            const int CACHE_LINE_SIZE = 64;
            auto f = *from->stack.pointer_ref();
            __builtin_prefetch(f, 1);
            // __builtin_prefetch((char*)f + CACHE_LINE_SIZE, 1);
            auto t = *to->stack.pointer_ref();
            __builtin_prefetch(t, 0);
            // __builtin_prefetch((char*)t + CACHE_LINE_SIZE, 0);
#endif
        }
        Switch remove_current(states new_state) const {
            assert(!current->single());
            auto from = current;