IRC Sections 1014 and 1015 (Basis Step-up and Basis of property acquired by gifts and transfers in trust)

1015(b) If the property was acquired by a transfer in trust (other than by a transfer in trust by a gift, bequest, or devise), the basis shall be the same as it would be in the hands of the grantor increased in the amount of gain or decreased in the amount of loss recognized to the grantor on such transfer under the law applicable to the year in which the transfer was made. Does this applies when the trust buys the property from the grantor?

1014(b)(2) applies to revocable trust?

1014(b)(3). Does this provision applies to irrevocable grantor trusts?