arith.lisp

开源跨平台Lisp编译器

    'sb!vm::%lea-smod30))

#+sb-xc-host
(progn
  (defun sb!vm::%lea-mod32 (base index scale disp)
    (ldb (byte 32 0) (%lea base index scale disp)))
  (defun sb!vm::%lea-smod30 (base index scale disp)
    (mask-signed-field 30 (%lea base index scale disp))))
#-sb-xc-host
(progn
  (defun sb!vm::%lea-mod32 (base index scale disp)
    (let ((base (logand base #xffffffff))
          (index (logand index #xffffffff)))
      ;; can't use modular version of %LEA, as we only have VOPs for
      ;; constant SCALE and DISP.
      (ldb (byte 32 0) (+ base (* index scale) disp))))
  (defun sb!vm::%lea-smod30 (base index scale disp)
    (let ((base (mask-signed-field 30 base))
          (index (mask-signed-field 30 index)))
      ;; can't use modular version of %LEA, as we only have VOPs for
      ;; constant SCALE and DISP.
      (mask-signed-field 30 (+ base (* index scale) disp)))))

(in-package "SB!VM")

(define-vop (%lea-mod32/unsigned=>unsigned
             %lea/unsigned=>unsigned)
  (:translate %lea-mod32))
(define-vop (%lea-smod30/fixnum=>fixnum
             %lea/fixnum=>fixnum)
  (:translate %lea-smod30))

;;; logical operations
(define-modular-fun lognot-mod32 (x) lognot :untagged nil 32)
(define-vop (lognot-mod32/word=>unsigned)
  (:translate lognot-mod32)
  (:args (x :scs (unsigned-reg signed-reg unsigned-stack signed-stack) :target r
            :load-if (not (and (or (sc-is x unsigned-stack)
                                   (sc-is x signed-stack))
                               (or (sc-is r unsigned-stack)
                                   (sc-is r signed-stack))
                               (location= x r)))))
  (:arg-types unsigned-num)
  (:results (r :scs (unsigned-reg)
               :load-if (not (and (or (sc-is x unsigned-stack)
                                      (sc-is x signed-stack))
                                  (or (sc-is r unsigned-stack)
                                      (sc-is r signed-stack))
                                  (sc-is r unsigned-stack)
                                  (location= x r)))))
  (:result-types unsigned-num)
  (:policy :fast-safe)
  (:generator 1
    (move r x)
    (inst not r)))

(define-source-transform logeqv (&rest args)
  (if (oddp (length args))
      `(logxor ,@args)
      `(lognot (logxor ,@args))))
(define-source-transform logandc1 (x y)
  `(logand (lognot ,x) ,y))
(define-source-transform logandc2 (x y)
  `(logand ,x (lognot ,y)))
(define-source-transform logorc1 (x y)
  `(logior (lognot ,x) ,y))
(define-source-transform logorc2 (x y)
  `(logior ,x (lognot ,y)))
(define-source-transform lognor (x y)
  `(lognot (logior ,x ,y)))
(define-source-transform lognand (x y)
  `(lognot (logand ,x ,y)))

;;;; bignum stuff

(define-vop (bignum-length get-header-data)
  (:translate sb!bignum:%bignum-length)
  (:policy :fast-safe))

(define-vop (bignum-set-length set-header-data)
  (:translate sb!bignum:%bignum-set-length)
  (:policy :fast-safe))

(define-full-reffer bignum-ref * bignum-digits-offset other-pointer-lowtag
  (unsigned-reg) unsigned-num sb!bignum:%bignum-ref)
(define-full-reffer+offset bignum-ref-with-offset *
  bignum-digits-offset other-pointer-lowtag
  (unsigned-reg) unsigned-num sb!bignum:%bignum-ref-with-offset)
(define-full-setter bignum-set * bignum-digits-offset other-pointer-lowtag
  (unsigned-reg) unsigned-num sb!bignum:%bignum-set)

(define-vop (digit-0-or-plus)
  (:translate sb!bignum:%digit-0-or-plusp)
  (:policy :fast-safe)
  (:args (digit :scs (unsigned-reg)))
  (:arg-types unsigned-num)
  (:conditional)
  (:info target not-p)
  (:generator 3
    (inst or digit digit)
    (inst jmp (if not-p :s :ns) target)))


;;; For add and sub with carry the sc of carry argument is any-reg so
;;; that it may be passed as a fixnum or word and thus may be 0, 1, or
;;; 4. This is easy to deal with and may save a fixnum-word
;;; conversion.
(define-vop (add-w/carry)
  (:translate sb!bignum:%add-with-carry)
  (:policy :fast-safe)
  (:args (a :scs (unsigned-reg) :target result)
         (b :scs (unsigned-reg unsigned-stack) :to :eval)
         (c :scs (any-reg) :target temp))
  (:arg-types unsigned-num unsigned-num positive-fixnum)
  (:temporary (:sc any-reg :from (:argument 2) :to :eval) temp)
  (:results (result :scs (unsigned-reg) :from (:argument 0))
            (carry :scs (unsigned-reg)))
  (:result-types unsigned-num positive-fixnum)
  (:generator 4
    (move result a)
    (move temp c)
    (inst neg temp) ; Set the carry flag to 0 if c=0 else to 1
    (inst adc result b)
    (inst mov carry 0)
    (inst adc carry carry)))

;;; Note: the borrow is 1 for no borrow and 0 for a borrow, the opposite
;;; of the x86 convention.
(define-vop (sub-w/borrow)
  (:translate sb!bignum:%subtract-with-borrow)
  (:policy :fast-safe)
  (:args (a :scs (unsigned-reg) :to :eval :target result)
         (b :scs (unsigned-reg unsigned-stack) :to :result)
         (c :scs (any-reg control-stack)))
  (:arg-types unsigned-num unsigned-num positive-fixnum)
  (:results (result :scs (unsigned-reg) :from :eval)
            (borrow :scs (unsigned-reg)))
  (:result-types unsigned-num positive-fixnum)
  (:generator 5
    (inst cmp c 1) ; Set the carry flag to 1 if c=0 else to 0
    (move result a)
    (inst sbb result b)
    (inst mov borrow 1)
    (inst sbb borrow 0)))


(define-vop (bignum-mult-and-add-3-arg)
  (:translate sb!bignum:%multiply-and-add)
  (:policy :fast-safe)
  (:args (x :scs (unsigned-reg) :target eax)
         (y :scs (unsigned-reg unsigned-stack))
         (carry-in :scs (unsigned-reg unsigned-stack)))
  (:arg-types unsigned-num unsigned-num unsigned-num)
  (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 0)
                   :to (:result 1) :target lo) eax)
  (:temporary (:sc unsigned-reg :offset edx-offset :from (:argument 1)
                   :to (:result 0) :target hi) edx)
  (:results (hi :scs (unsigned-reg))
            (lo :scs (unsigned-reg)))
  (:result-types unsigned-num unsigned-num)
  (:generator 20
    (move eax x)
    (inst mul eax y)
    (inst add eax carry-in)
    (inst adc edx 0)
    (move hi edx)
    (move lo eax)))

(define-vop (bignum-mult-and-add-4-arg)
  (:translate sb!bignum:%multiply-and-add)
  (:policy :fast-safe)
  (:args (x :scs (unsigned-reg) :target eax)
         (y :scs (unsigned-reg unsigned-stack))
         (prev :scs (unsigned-reg unsigned-stack))
         (carry-in :scs (unsigned-reg unsigned-stack)))
  (:arg-types unsigned-num unsigned-num unsigned-num unsigned-num)
  (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 0)
                   :to (:result 1) :target lo) eax)
  (:temporary (:sc unsigned-reg :offset edx-offset :from (:argument 1)
                   :to (:result 0) :target hi) edx)
  (:results (hi :scs (unsigned-reg))
            (lo :scs (unsigned-reg)))
  (:result-types unsigned-num unsigned-num)
  (:generator 20
    (move eax x)
    (inst mul eax y)
    (inst add eax prev)
    (inst adc edx 0)
    (inst add eax carry-in)
    (inst adc edx 0)
    (move hi edx)
    (move lo eax)))


(define-vop (bignum-mult)
  (:translate sb!bignum:%multiply)
  (:policy :fast-safe)
  (:args (x :scs (unsigned-reg) :target eax)
         (y :scs (unsigned-reg unsigned-stack)))
  (:arg-types unsigned-num unsigned-num)
  (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 0)
                   :to (:result 1) :target lo) eax)
  (:temporary (:sc unsigned-reg :offset edx-offset :from (:argument 1)
                   :to (:result 0) :target hi) edx)
  (:results (hi :scs (unsigned-reg))
            (lo :scs (unsigned-reg)))
  (:result-types unsigned-num unsigned-num)
  (:generator 20
    (move eax x)
    (inst mul eax y)
    (move hi edx)
    (move lo eax)))

(define-vop (bignum-lognot lognot-mod32/word=>unsigned)
  (:translate sb!bignum:%lognot))

(define-vop (fixnum-to-digit)
  (:translate sb!bignum:%fixnum-to-digit)
  (:policy :fast-safe)
  (:args (fixnum :scs (any-reg control-stack) :target digit))
  (:arg-types tagged-num)
  (:results (digit :scs (unsigned-reg)
                   :load-if (not (and (sc-is fixnum control-stack)
                                      (sc-is digit unsigned-stack)
                                      (location= fixnum digit)))))
  (:result-types unsigned-num)
  (:generator 1
    (move digit fixnum)
    (inst sar digit 2)))

(define-vop (bignum-floor)
  (:translate sb!bignum:%floor)
  (:policy :fast-safe)
  (:args (div-high :scs (unsigned-reg) :target edx)
         (div-low :scs (unsigned-reg) :target eax)
         (divisor :scs (unsigned-reg unsigned-stack)))
  (:arg-types unsigned-num unsigned-num unsigned-num)
  (:temporary (:sc unsigned-reg :offset eax-offset :from (:argument 1)
                   :to (:result 0) :target quo) eax)
  (:temporary (:sc unsigned-reg :offset edx-offset :from (:argument 0)
                   :to (:result 1) :target rem) edx)
  (:results (quo :scs (unsigned-reg))
            (rem :scs (unsigned-reg)))
  (:result-types unsigned-num unsigned-num)
  (:generator 300
    (move edx div-high)
    (move eax div-low)
    (inst div eax divisor)
    (move quo eax)
    (move rem edx)))

(define-vop (signify-digit)
  (:translate sb!bignum:%fixnum-digit-with-correct-sign)
  (:policy :fast-safe)
  (:args (digit :scs (unsigned-reg unsigned-stack) :target res))
  (:arg-types unsigned-num)
  (:results (res :scs (any-reg signed-reg)
                 :load-if (not (and (sc-is digit unsigned-stack)
                                    (sc-is res control-stack signed-stack)
                                    (location= digit res)))))
  (:result-types signed-num)
  (:generator 1
    (move res digit)
    (when (sc-is res any-reg control-stack)
      (inst shl res 2))))

(define-vop (digit-ashr)
  (:translate sb!bignum:%ashr)
  (:policy :fast-safe)
  (:args (digit :scs (unsigned-reg unsigned-stack) :target result)
         (count :scs (unsigned-reg) :target ecx))
  (:arg-types unsigned-num positive-fixnum)
  (:temporary (:sc unsigned-reg :offset ecx-offset :from (:argument 1)) ecx)
  (:results (result :scs (unsigned-reg) :from (:argument 0)
                    :load-if (not (and (sc-is result unsigned-stack)
                                       (location= digit result)))))
  (:result-types unsigned-num)
  (:generator 2
    (move result digit)
    (move ecx count)
    (inst sar result :cl)))

(define-vop (digit-ashr/c)
  (:translate sb!bignum:%ashr)
  (:policy :fast-safe)
  (:args (digit :scs (unsigned-reg unsigned-stack) :target result))
  (:arg-types unsigned-num (:constant (integer 0 31)))
  (:info count)
  (:results (result :scs (unsigned-reg) :from (:argument 0)
                    :load-if (not (and (sc-is result unsigned-stack)
                                       (location= digit result)))))
  (:result-types unsigned-num)
  (:generator 1
    (move result digit)
    (inst sar result count)))

(define-vop (digit-lshr digit-ashr)
  (:translate sb!bignum:%digit-logical-shift-right)
  (:generator 1
    (move result digit)
    (move ecx count)
    (inst shr result :cl)))

(define-vop (digit-ashl digit-ashr)
  (:translate sb!bignum:%ashl)
  (:generator 1
    (move result digit)
    (move ecx count)
    (inst shl result :cl)))

;;;; static functions

(define-static-fun two-arg-/ (x y) :translate /)

(define-static-fun two-arg-gcd (x y) :translate gcd)
(define-static-fun two-arg-lcm (x y) :translate lcm)

(define-static-fun two-arg-and (x y) :translate logand)
(define-static-fun two-arg-ior (x y) :translate logior)
(define-static-fun two-arg-xor (x y) :translate logxor)


;;; Support for the Mersenne Twister, MT19937, random number generator
;;; due to Matsumoto and Nishimura.
;;;
;;; Makoto Matsumoto and T. Nishimura, "Mersenne twister: A
;;; 623-dimensionally equidistributed uniform pseudorandom number
;;; generator.", ACM Transactions on Modeling and Computer Simulation,
;;; 1997, to appear.
;;;
;;; State:
;;;  0-1:   Constant matrix A. [0, #x9908b0df] (not used here)
;;;  2:     Index; init. to 1.
;;;  3-626: State.
(defknown random-mt19937 ((simple-array (unsigned-byte 32) (*)))
  (unsigned-byte 32) ())
(define-vop (random-mt19937)
  (:policy :fast-safe)
  (:translate random-mt19937)
  (:args (state :scs (descriptor-reg) :to :result))
  (:arg-types simple-array-unsigned-byte-32)
  (:temporary (:sc unsigned-reg :from (:eval 0) :to :result) k)
  (:temporary (:sc unsigned-r