New Issue: Is the BigInteger swap method optimal?

17721, "lydia-duncan", "Is the BigInteger swap method optimal?", "2021-05-13T16:18:47Z"

bigint.swap() doesn't call the GMP swap function if the values are remote, but the GMP swap function claims that it swaps the values efficiently (which I suppose could mean that it only swaps different sections or whatever). Are we potentially taking a less optimal approach by performing the action ourselves in this case?