updateSlot

Extract the current value of the slot, pass it to the supplied inline Kotlin function, and write the result back to the slot.

Extract the current value of the Long slot, pass it to the supplied inline Kotlin function, and write the resulting Long back to the slot.

Extract the current Int value of the BitField, pass it to the supplied inline Kotlin function, and write the result back to the BitField. Note that this is not atomic, so other fields encoded in the same Long field may get clobbered if simultaneously updated by multiple threads.