sync.c

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#include <core/sync.h>
 
#include <core/core.h>
 
bool sync_thread_barrier(void)
{
        static _Thread_local unsigned phase;
        static atomic_uint cs[2];
        atomic_uint *c = cs + (phase & 1U);
 
        bool l;
        unsigned r;
        if (phase & 2U) {
                l = atomic_fetch_add_explicit(c, -1, memory_order_release) == 1;
                do {
                        r = atomic_load_explicit(c, memory_order_relaxed);
                } while(r);
        } else {
                l = !atomic_fetch_add_explicit(c, 1, memory_order_release);
                rid_t thr_cnt = n_threads;
                do {
                        r = atomic_load_explicit(c, memory_order_relaxed);
                } while(r != thr_cnt);
        }
 
        phase = (phase + 1) & 3U;
        return l;
}