var x uint32
	x = 1
	ptr := &x
	b.RunParallel(func(pb *testing.PB) {
		for pb.Next() {
			atomic.Cas(ptr, 1, 0)
			atomic.Cas(ptr, 0, 1)
		}
	})
}

func BenchmarkCas64(b *testing.B) {
	var x uint64
	x = 1
	ptr := &x
	b.RunParallel(func(pb *testing.PB) {
		for pb.Next() {
			atomic.Cas64(ptr, 1, 0)
			atomic.Cas64(ptr, 0, 1)
		}
	})
}