func roundUp(x, to uint32) uint32 {
	if to == 0 || to&(to-1) != 0 {
		log.Fatalf("rounded up to a value that is not a power of 2: %d\n", to)
	}
	return (x + to - 1) &^ (to - 1)
}

// splitImm24uScaled splits an immediate into a scaled 12 bit unsigned lo value
// and an unscaled shifted 12 bit unsigned hi value. These are typically used
// by adding or subtracting the hi value and using the lo value as the offset