arith.lisp

开源跨平台Lisp编译器

      ;; overflow.
      (inst sll result number amount)
      (inst neg ndesc amount)
      (inst cmp ndesc 31)
      (if (member :sparc-v9 *backend-subfeatures*)
          (progn
            (inst cmove :ge ndesc 31)
            (inst sra result number ndesc))
          (progn
            (inst b :le done)
            (inst sra result number ndesc)
            (inst sra result number 31)))
      (emit-label done))))

(define-vop (fast-ash-c/signed=>signed)
  (:note "inline constant ASH")
  (:args (number :scs (signed-reg)))
  (:info count)
  (:arg-types signed-num (:constant integer))
  (:results (result :scs (signed-reg)))
  (:result-types signed-num)
  (:translate ash)
  (:policy :fast-safe)
  (:generator 4
    (cond
      ((< count 0) (inst sra result number (min (- count) 31)))
      ((> count 0) (inst sll result number (min count 31)))
      (t (bug "identity ASH not transformed away")))))

(define-vop (fast-ash/unsigned=>unsigned)
  (:note "inline ASH")
  (:args (number :scs (unsigned-reg) :to :save)
         (amount :scs (signed-reg) :to :save))
  (:arg-types unsigned-num signed-num)
  (:results (result :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:translate ash)
  (:policy :fast-safe)
  (:temporary (:sc non-descriptor-reg) ndesc)
  (:generator 5
    (let ((done (gen-label)))
      (inst cmp amount)
      (inst b :ge done)
      ;; The result-type assures us that this shift will not
      ;; overflow.
      (inst sll result number amount)
      (inst neg ndesc amount)
      (inst cmp ndesc 32)
      (if (member :sparc-v9 *backend-subfeatures*)
          (progn
            (inst srl result number ndesc)
            (inst cmove :ge result zero-tn))
          (progn
            (inst b :lt done)
            (inst srl result number ndesc)
            (move result zero-tn)))
      (emit-label done))))

(define-vop (fast-ash-c/unsigned=>unsigned)
  (:note "inline constant ASH")
  (:args (number :scs (unsigned-reg)))
  (:info count)
  (:arg-types unsigned-num (:constant integer))
  (:results (result :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:translate ash)
  (:policy :fast-safe)
  (:generator 4
    (cond
      ((< count -31) (move result zero-tn))
      ((< count 0) (inst srl result number (min (- count) 31)))
      ((> count 0) (inst sll result number (min count 31)))
      (t (bug "identity ASH not transformed away")))))

;; Some special cases where we know we want a left shift.  Just do the
;; shift, instead of checking for the sign of the shift.
(macrolet
    ((def (name sc-type type result-type cost)
       `(define-vop (,name)
         (:note "inline ASH")
         (:translate ash)
         (:args (number :scs (,sc-type))
                (amount :scs (signed-reg unsigned-reg immediate)))
         (:arg-types ,type positive-fixnum)
         (:results (result :scs (,result-type)))
         (:result-types ,type)
         (:policy :fast-safe)
         (:generator ,cost
          ;; The result-type assures us that this shift will not
          ;; overflow. And for fixnums, the zero bits that get
          ;; shifted in are just fine for the fixnum tag.
          (sc-case amount
           ((signed-reg unsigned-reg)
            (inst sll result number amount))
           (immediate
            (let ((amount (tn-value amount)))
              (aver (>= amount 0))
              (inst sll result number amount))))))))
  (def fast-ash-left/signed=>signed signed-reg signed-num signed-reg 3)
  (def fast-ash-left/fixnum=>fixnum any-reg tagged-num any-reg 2)
  (def fast-ash-left/unsigned=>unsigned unsigned-reg unsigned-num unsigned-reg 3))


(define-vop (signed-byte-32-len)
  (:translate integer-length)
  (:note "inline (signed-byte 32) integer-length")
  (:policy :fast-safe)
  (:args (arg :scs (signed-reg) :target shift))
  (:arg-types signed-num)
  (:results (res :scs (any-reg)))
  (:result-types positive-fixnum)
  (:temporary (:scs (non-descriptor-reg) :from (:argument 0)) shift)
  (:generator 30
    (let ((loop (gen-label))
          (test (gen-label)))
      (inst addcc shift zero-tn arg)
      (inst b :ge test)
      (move res zero-tn)
      (inst b test)
      (inst not shift)

      (emit-label loop)
      (inst add res (fixnumize 1))

      (emit-label test)
      (inst cmp shift)
      (inst b :ne loop)
      (inst srl shift 1))))

(define-vop (unsigned-byte-32-count)
  (:translate logcount)
  (:note "inline (unsigned-byte 32) logcount")
  (:policy :fast-safe)
  (:args (arg :scs (unsigned-reg)))
  (:arg-types unsigned-num)
  (:results (res :scs (unsigned-reg)))
  (:result-types positive-fixnum)
  (:temporary (:scs (non-descriptor-reg) :from (:argument 0)) mask temp)
  (:generator 35
      (move res arg)

      (dolist (stuff '((1 #x55555555) (2 #x33333333) (4 #x0f0f0f0f)
                       (8 #x00ff00ff) (16 #x0000ffff)))
        (destructuring-bind (shift bit-mask)
            stuff
          ;; Set mask
          (inst sethi mask (ldb (byte 22 10) bit-mask))
          (inst add mask (ldb (byte 10 0) bit-mask))

          (inst and temp res mask)
          (inst srl res shift)
          (inst and res mask)
          (inst add res temp)))))


;;; Multiply and Divide.

(define-vop (fast-v8-*/fixnum=>fixnum fast-fixnum-binop)
  (:temporary (:scs (non-descriptor-reg)) temp)
  (:translate *)
  (:guard (or (member :sparc-v8 *backend-subfeatures*)
              (and (member :sparc-v9 *backend-subfeatures*)
                   (not (member :sparc-64 *backend-subfeatures*)))))
  (:generator 2
    ;; The cost here should be less than the cost for
    ;; */signed=>signed.  Why?  A fixnum product using signed=>signed
    ;; has to convert both args to signed-nums.  But using this, we
    ;; don't have to and that saves an instruction.
    (inst sra temp y n-fixnum-tag-bits)
    (inst smul r x temp)))

(define-vop (fast-v8-*-c/fixnum=>fixnum fast-safe-arith-op)
  (:args (x :target r :scs (any-reg zero)))
  (:info y)
  (:arg-types tagged-num
              (:constant (and (signed-byte 13) (not (integer 0 0)))))
  (:results (r :scs (any-reg)))
  (:result-types tagged-num)
  (:note "inline fixnum arithmetic")
  (:translate *)
  (:guard (or (member :sparc-v8 *backend-subfeatures*)
              (and (member :sparc-v9 *backend-subfeatures*)
                   (not (member :sparc-64 *backend-subfeatures*)))))
  (:generator 1
    (inst smul r x y)))

(define-vop (fast-v8-*/signed=>signed fast-signed-binop)
  (:translate *)
  (:guard (or (member :sparc-v8 *backend-subfeatures*)
              (and (member :sparc-v9 *backend-subfeatures*)
                   (not (member :sparc-64 *backend-subfeatures*)))))
  (:generator 3
    (inst smul r x y)))

(define-vop (fast-v8-*-c/signed=>signed fast-signed-binop-c)
  (:translate *)
  (:guard (or (member :sparc-v8 *backend-subfeatures*)
              (and (member :sparc-v9 *backend-subfeatures*)
                   (not (member :sparc-64 *backend-subfeatures*)))))
  (:generator 2
    (inst smul r x y)))

(define-vop (fast-v8-*/unsigned=>unsigned fast-unsigned-binop)
  (:translate *)
  (:guard (or (member :sparc-v8 *backend-subfeatures*)
              (and (member :sparc-v9 *backend-subfeatures*)
                   (not (member :sparc-64 *backend-subfeatures*)))))
  (:generator 3
    (inst umul r x y)))

(define-vop (fast-v8-*-c/unsigned=>unsigned fast-unsigned-binop-c)
  (:translate *)
  (:guard (or (member :sparc-v8 *backend-subfeatures*)
              (and (member :sparc-v9 *backend-subfeatures*)
                   (not (member :sparc-64 *backend-subfeatures*)))))
  (:generator 2
    (inst umul r x y)))

;; The smul and umul instructions are deprecated on the Sparc V9.  Use
;; mulx instead.
(define-vop (fast-v9-*/fixnum=>fixnum fast-fixnum-binop)
  (:temporary (:scs (non-descriptor-reg)) temp)
  (:translate *)
  (:guard (member :sparc-64 *backend-subfeatures*))
  (:generator 4
    (inst sra temp y n-fixnum-tag-bits)
    (inst mulx r x temp)))

(define-vop (fast-v9-*/signed=>signed fast-signed-binop)
  (:translate *)
  (:guard (member :sparc-64 *backend-subfeatures*))
  (:generator 3
    (inst mulx r x y)))

(define-vop (fast-v9-*/unsigned=>unsigned fast-unsigned-binop)
  (:translate *)
  (:guard (member :sparc-64 *backend-subfeatures*))
  (:generator 3
    (inst mulx r x y)))


;;;; Modular functions:
(define-modular-fun lognot-mod32 (x) lognot :untagged nil 32)
(define-vop (lognot-mod32/unsigned=>unsigned)
  (:translate lognot-mod32)
  (:args (x :scs (unsigned-reg)))
  (:arg-types unsigned-num)
  (:results (res :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:policy :fast-safe)
  (:generator 1
    (inst not res x)))

(macrolet
    ((define-modular-backend (fun &optional constantp)
       (let ((mfun-name (symbolicate fun '-mod32))
             (modvop (symbolicate 'fast- fun '-mod32/unsigned=>unsigned))
             (modcvop (symbolicate 'fast- fun '-mod32-c/unsigned=>unsigned))
             (vop (symbolicate 'fast- fun '/unsigned=>unsigned))
             (cvop (symbolicate 'fast- fun '-c/unsigned=>unsigned)))
         `(progn
            (define-modular-fun ,mfun-name (x y) ,fun :untagged nil 32)
            (define-vop (,modvop ,vop)
              (:translate ,mfun-name))
            ,@(when constantp
                `((define-vop (,modcvop ,cvop)
                    (:translate ,mfun-name))))))))
  (define-modular-backend + t)
  (define-modular-backend - t)
  (define-modular-backend logeqv t)
  (define-modular-backend logandc1)
  (define-modular-backend logandc2 t)
  (define-modular-backend logorc1)
  (define-modular-backend logorc2 t))

(define-source-transform lognand (x y)
  `(lognot (logand ,x ,y)))
(define-source-transform lognor (x y)
  `(lognot (logior ,x ,y)))

(define-vop (fast-ash-left-mod32-c/unsigned=>unsigned
             fast-ash-c/unsigned=>unsigned)
  (:translate ash-left-mod32))

(define-vop (fast-ash-left-mod32/unsigned=>unsigned
             fast-ash-left/unsigned=>unsigned))
(deftransform ash-left-mod32 ((integer count)
                              ((unsigned-byte 32) (unsigned-byte 5)))
  (when (sb!c::constant-lvar-p count)
    (sb!c::give-up-ir1-transform))
  '(%primitive fast-ash-left-mod32/unsigned=>unsigned integer count))

;;;; Binary conditional VOPs:

(define-vop (fast-conditional)
  (:conditional)
  (:info target not-p)
  (:effects)
  (:affected)
  (:policy :fast-safe))

(define-vop (fast-conditional/fixnum fast-conditional)
  (:args (x :scs (any-reg zero))
         (y :scs (any-reg zero)))
  (:arg-types tagged-num tagged-num)
  (:note "inline fixnum comparison"))

(define-vop (fast-conditional-c/fixnum fast-conditional/fixnum)
  (:args (x :scs (any-reg zero)))
  (:arg-types tagged-num (:constant (signed-byte 11)))
  (:info target not-p y))

(define-vop (fast-conditional/signed fast-conditional)
  (:args (x :scs (signed-reg zero))
         (y :scs (signed-reg zero)))
  (:arg-types signed-num signed-num)
  (:note "inline (signed-byte 32) comparison"))

(define-vop (fast-conditional-c/signed fast-conditional/signed)
  (:args (x :scs (signed-reg zero)))
  (:arg-types signed-num (:constant (signed-byte 13)))
  (:info target not-p y))

(define-vop (fast-conditional/unsigned fast-conditional)
  (:args (x :scs (unsigned-reg zero))
         (y :scs (unsigned-reg zero)))
  (:arg-types unsigned-num unsigned-num)
  (:note "inline (unsigned-byte 32) comparison"))

(define-vop (fast-conditional-c/unsigned fast-conditional/unsigned)
  (:args (x :scs (unsigned-reg zero)))
  (:arg-types unsigned-num (:constant (unsigned-byte 12)))
  (:info target not-p y))


(defmacro define-conditional-vop (tran cond unsigned not-cond not-unsigned)
  `(progn
     ,@(mapcar (lambda (suffix cost signed)
                 (unless (and (member suffix '(/fixnum -c/fixnum))
                              (eq tran 'eql))
                   `(define-vop (,(intern (format nil "~:@(FAST-IF-~A~A~)"
                                                  tran suffix))
                                 ,(intern
                                   (format nil "~:@(FAST-CONDITIONAL~A~)"
                                           suffix)))
                     (:translate ,tran)
                     (:generator ,cost
                      (inst cmp x
                       ,(if (eq suffix '-c/fixnum) '(fixnumize y) 'y))
                      (inst b (if not-p
                                  ,(if signed not-cond not-unsigned)
                                  ,(if signed cond unsigned))
                       target)
                      (inst nop)))))
               '(/fixnum -c/fixnum /signed -c/signed /unsigned -c/unsigned)
               '(4 3 6 5 6 5)
               '(t t t t nil nil))))

(define-conditional-vop < :lt :ltu :ge :geu)

(define-conditional-vop > :gt :gtu :le :leu)

(define-conditional-vop eql :eq :eq :ne :ne)

;;; EQL/FIXNUM is funny because the first arg can be of any type, not just a
;;; known fixnum.

;;; These versions specify a fixnum restriction on their first arg.  We have
;;; also generic-eql/fixnum VOPs which are the same, but have no restriction on
;;; the first arg and a higher cost.  The reason for doing this is to prevent
;;; fixnum specific operations from being used on word integers, spuriously
;;; consing the argument.
;;;

(define-vop (fast-eql/fixnum fast-conditional)
  (:args (x :scs (any-reg descriptor-reg zero))
         (y :scs (any-reg zero)))
  (:arg-types tagged-num tagged-num)
  (:note "inline fixnum comparison")
  (:translate eql)
  (:generator 4
    (inst cmp x y)
    (inst b (if not-p :ne :eq) target)
    (inst nop)))
;;;
(define-vop (generic-eql/fixnum fast-eql/fixnum)
  (:arg-types * tagged-num)
  (:variant-cost 7))

(define-vop (fast-eql-c/fixnum fast-conditional/fixnum)
  (:args (x :scs (any-reg descriptor-reg zero)))
  (:arg-types tagged-num (:constant (signed-byte 11)))
  (:info target not-p y)
  (:translate eql)
  (:generator 2
    (inst cmp x (fixnumize y))
    (inst b (if not-p :ne :eq) target)
    (inst nop)))
;;;
(define-vop (generic-eql-c/fixnum fast-eql-c/fixnum)
  (:arg-types * (:constant (signed-byte 11)))
  (:variant-cost 6))


;;;; 32-bit logical operations
(define-vop (merge-bits)
  (:translate merge-bits)