gistfile1.lisp

(define-vop (bignum-mult-and-add-3-arg)
  (:translate sb!bignum:%multiply-and-add)
  (:policy :fast-safe)
  (:args (x :scs (unsigned-reg) :to :result)
         (y :scs (unsigned-reg) :to :result)
         (carry-in :scs (unsigned-reg) :target lo))
  (:arg-types unsigned-num unsigned-num unsigned-num)
  (:results (hi :scs (unsigned-reg) :from :eval)
            (lo :scs (unsigned-reg) :from (:argument 2)))
  (:result-types unsigned-num unsigned-num)
  (:generator 2
    (move lo carry-in)
    (inst eor hi hi hi) ; call this zeroize and figure it out later
    (inst umlal lo hi x y)))

(define-vop (bignum-mult-and-add-4-arg)
  (:translate sb!bignum:%multiply-and-add)
  (:policy :fast-safe)
  (:args (x :scs (unsigned-reg) :to :result)
         (y :scs (unsigned-reg) :to :result)
         (prev :scs (unsigned-reg) :to :eval)
         (carry-in :scs (unsigned-reg) :to :eval))
  (:arg-types unsigned-num unsigned-num unsigned-num unsigned-num)
  (:results (hi :scs (unsigned-reg) :from :eval)
            (lo :scs (unsigned-reg) :from :eval))
  (:result-types unsigned-num unsigned-num)
  (:generator 2
    (inst adds lo carry-in prev)
    (inst eor hi hi hi)
    (inst mov :cs hi 1)
    (inst umlal lo hi x y)))