lared as "coherent" guarantees only that the results of
            stores will be immediately visible to shader invocations using
            similarly-declared variables; calling <code class="function">glMemoryBarrier</code> is required to ensure
            that the stores are visible to other operations.
        </p>
        <p>
            The following guidelines may be helpful in choosing when to use coherent
            memory accesses and when to use barriers.
        </p>
        <p>
            <