public boolean compareAndSet(long expect, long update) {
        return casVal(expect, update);
    }
Atomically sets the value to the given updated value
if the current value {@code ==} the expected value.

@param expect the expected value
@param update the new value
@return {@code true} if successful. False return indicates that
the actual value was not equal to the expected value.
@see java.util.concurrent.atomic.AtomicLong#compareAndSet(long, long)
jctools-core/src/main/java/org/jctools/util/PaddedAtomicLong.java