In general
If—
(A)#
the property is acquired by gift on or after September 2, 1958 , the basis shall be the basis determined under subsection (a), increased (but not above the fair market value of the property at the time of the gift) by the amount of gift tax paid with respect to such gift, or
(B)#
the property was acquired by gift before September 2, 1958 , and has not been sold, exchanged, or otherwise disposed of before such date, the basis of the property shall be increased on such date by the amount of gift tax paid with respect to such gift, but such increase shall not exceed an amount equal to the amount by which the fair market value of the property at the time of the gift exceeded the basis of the property in the hands of the donor at the time of the gift.