(pseudo-atomic (:extra (pad-data-block (+ bignum-digits-offset 3)))
(inst bis alloc-tn other-pointer-lowtag y)
(storew header y 0 other-pointer-lowtag)
(pseudo-atomic (:extra (pad-data-block (+ bignum-digits-offset 3)))
(inst bis alloc-tn other-pointer-lowtag y)
(storew header y 0 other-pointer-lowtag)