;;; -*- Package: PPC -*-
;;;
;;; **********************************************************************
;;; This code was written as part of the Spice Lisp project at
;;; Carnegie-Mellon University, and has been placed in the public domain.
;;; If you want to use this code or any part of Spice Lisp, please contact
;;; Scott Fahlman (FAHLMAN@CMUC). 
;;; **********************************************************************
;;;
;;; $Header: /project/cmucl/cvsroot/src/compiler/ppc/arith.lisp,v 1.15 2008-08-13 12:21:28 rtoy Rel $
;;;
;;;    This file contains the VM definition arithmetic VOPs for the MIPS.
;;;
;;; Written by Rob MacLachlan
;;;
;;; Converted by William Lott.
;;; 

(in-package "PPC")



;;;; Unary operations.

(define-vop (fast-safe-arith-op)
  (:policy :fast-safe)
  (:effects)
  (:affected))


(define-vop (fixnum-unop fast-safe-arith-op)
  (:args (x :scs (any-reg)))
  (:results (res :scs (any-reg)))
  (:note "inline fixnum arithmetic")
  (:arg-types tagged-num)
  (:result-types tagged-num))

(define-vop (signed-unop fast-safe-arith-op)
  (:args (x :scs (signed-reg)))
  (:results (res :scs (signed-reg)))
  (:note "inline (signed-byte 32) arithmetic")
  (:arg-types signed-num)
  (:result-types signed-num))

(define-vop (fast-negate/fixnum fixnum-unop)
  (:translate %negate)
  (:generator 1
    (inst neg res x)))

(define-vop (fast-negate/signed signed-unop)
  (:translate %negate)
  (:generator 2
    (inst neg res x)))

(define-vop (fast-lognot/fixnum fixnum-unop)
  (:translate lognot)
  (:generator 2
    (inst xori res x (fixnumize -1))))

(define-vop (fast-lognot/signed signed-unop)
  (:translate lognot)
  (:generator 1
    (inst not res x)))



;;;; Binary fixnum operations.

;;; Assume that any constant operand is the second arg...

(define-vop (fast-fixnum-binop fast-safe-arith-op)
  (:args (x :target r :scs (any-reg zero))
	 (y :target r :scs (any-reg zero)))
  (:arg-types tagged-num tagged-num)
  (:results (r :scs (any-reg)))
  (:result-types tagged-num)
  (:note "inline fixnum arithmetic"))

(define-vop (fast-unsigned-binop fast-safe-arith-op)
  (:args (x :target r :scs (unsigned-reg zero))
	 (y :target r :scs (unsigned-reg zero)))
  (:arg-types unsigned-num unsigned-num)
  (:results (r :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:note "inline (unsigned-byte 32) arithmetic"))

(define-vop (fast-signed-binop fast-safe-arith-op)
  (:args (x :target r :scs (signed-reg zero))
	 (y :target r :scs (signed-reg zero)))
  (:arg-types signed-num signed-num)
  (:results (r :scs (signed-reg)))
  (:result-types signed-num)
  (:note "inline (signed-byte 32) arithmetic"))

(define-vop (fast-fixnum-binop-c fast-safe-arith-op)
  (:args (x :target r :scs (any-reg zero)))
  (:info y)
  (:arg-types tagged-num
	      (:constant (and (signed-byte 14) (not (integer 0 0)))))
  (:results (r :scs (any-reg)))
  (:result-types tagged-num)
  (:note "inline fixnum arithmetic"))

(define-vop (fast-fixnum-logop-c fast-safe-arith-op)
  (:args (x :target r :scs (any-reg zero)))
  (:info y)
  (:arg-types tagged-num
	      (:constant (and (unsigned-byte 14) (not (integer 0 0)))))
  (:results (r :scs (any-reg)))
  (:result-types tagged-num)
  (:note "inline fixnum logical op"))

(define-vop (fast-unsigned-binop-c fast-safe-arith-op)
  (:args (x :target r :scs (unsigned-reg zero)))
  (:info y)
  (:arg-types unsigned-num
	      (:constant (and (signed-byte 16) (not (integer 0 0)))))
  (:results (r :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:note "inline (unsigned-byte 32) arithmetic"))

(define-vop (fast-unsigned-logop-c fast-safe-arith-op)
  (:args (x :target r :scs (unsigned-reg zero)))
  (:info y)
  (:arg-types unsigned-num
	      (:constant (and (unsigned-byte 16) (not (integer 0 0)))))
  (:results (r :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:note "inline (unsigned-byte 32) logical op"))

(define-vop (fast-signed-binop-c fast-safe-arith-op)
  (:args (x :target r :scs (signed-reg zero)))
  (:info y)
  (:arg-types signed-num
	      (:constant (and (signed-byte 16) (not (integer 0 0)))))
  (:results (r :scs (signed-reg)))
  (:result-types signed-num)
  (:note "inline (signed-byte 32) arithmetic"))

(define-vop (fast-signed-logop-c fast-safe-arith-op)
  (:args (x :target r :scs (signed-reg zero)))
  (:info y)
  (:arg-types signed-num
	      (:constant (and (unsigned-byte 16) (not (integer 0 0)))))
  (:results (r :scs (signed-reg)))
  (:result-types signed-num)
  (:note "inline (signed-byte 32) arithmetic"))


(eval-when (:compile-toplevel :load-toplevel :execute)

(defmacro define-var-binop (translate untagged-penalty op
			    &optional arg-swap restore-fixnum-mask)
  `(progn
     (define-vop (,(symbolicate "FAST-" translate "/FIXNUM=>FIXNUM")
		  fast-fixnum-binop)
       (:translate ,translate)
       ,@(when restore-fixnum-mask
	       `((:temporary (:sc non-descriptor-reg) temp)))
       (:generator 2
	 ,(if arg-swap
	      `(inst ,op ,(if restore-fixnum-mask 'temp 'r) y x)
	      `(inst ,op ,(if restore-fixnum-mask 'temp 'r) x y))
	 ,@(when restore-fixnum-mask
		 ``(inst clrrwi r temp (1- lowtag-bits)))))
     (define-vop (,(symbolicate "FAST-" translate "/SIGNED=>SIGNED")
		  fast-signed-binop)
       (:translate ,translate)
       (:generator ,(1+ untagged-penalty)
	 ,(if arg-swap
	      `(inst ,op r y x)
	      `(inst ,op r x y))))
     (define-vop (,(symbolicate "FAST-" translate "/UNSIGNED=>UNSIGNED")
		  fast-unsigned-binop)
       (:translate ,translate)
       (:generator ,(1+ untagged-penalty)
	 ,(if arg-swap
	      `(inst ,op r y x)
	      `(inst ,op r x y))))))



(defmacro define-const-binop (translate untagged-penalty op
			      &optional arg-swap restore-fixnum-mask)
  `(progn
     (define-vop (,(symbolicate 'fast- translate '-c/fixnum=>fixnum)
		  fast-fixnum-binop-c)
       (:translate ,translate)
       (:generator 1
	 (inst ,op r x (fixnumize y))))
     (define-vop (,(symbolicate 'fast- translate '-c/signed=>signed)
		  fast-signed-binop-c)
       (:translate ,translate)
       (:generator ,untagged-penalty
	 (inst ,op r x y)))
     (define-vop (,(symbolicate 'fast- translate '-c/unsigned=>unsigned)
		  fast-unsigned-binop-c)
       (:translate ,translate)
       (:generator ,untagged-penalty
	 (inst ,op r x y)))))

(defmacro define-const-logop (translate untagged-penalty op)
  `(progn
     
     (define-vop (,(symbolicate 'fast- translate '-c/fixnum=>fixnum)
		  fast-fixnum-logop-c)
       (:translate ,translate)
       (:generator 1
	 (inst ,op r x (fixnumize y))))
     (define-vop (,(symbolicate 'fast- translate '-c/signed=>signed)
		  fast-signed-logop-c)
       (:translate ,translate)
       (:generator ,untagged-penalty
	 (inst ,op r x y)))
     (define-vop (,(symbolicate 'fast- translate '-c/unsigned=>unsigned)
		  fast-unsigned-logop-c)
       (:translate ,translate)
       (:generator ,untagged-penalty
	 (inst ,op r x y)))))

); eval-when

(define-var-binop + 4 add)
(define-var-binop - 4 sub)
(define-var-binop logand 2 and)
(define-var-binop logandc1 2 andc t)
(define-var-binop logandc2 2 andc)
(define-var-binop logior 2 or)
(define-var-binop logorc1 2 orc t t)
(define-var-binop logorc2 2 orc nil t)
(define-var-binop logxor 2 xor)
(define-var-binop logeqv 2 eqv nil t)
(define-var-binop lognand 2 nand nil t)
(define-var-binop lognor 2 nor nil t)

(define-const-binop + 4 addi)
(define-const-binop - 4 subi)
(define-const-logop logand 2 andi.)
(define-const-logop logior 2 ori)
(define-const-logop logxor 2 xori)


;;; Special logand cases: (logand signed unsigned) => unsigned

(define-vop (fast-logand/signed-unsigned=>unsigned
	     fast-logand/unsigned=>unsigned)
    (:args (x :scs (signed-reg))
	   (y :target r :scs (unsigned-reg)))
  (:arg-types signed-num unsigned-num))

(define-vop (fast-logand/unsigned-signed=>unsigned
	     fast-logand/unsigned=>unsigned)
    (:args (x :target r :scs (unsigned-reg))
	   (y :scs (signed-reg)))
  (:arg-types unsigned-num signed-num))

(define-vop (fast-logand-c/signed-unsigned=>unsigned fast-unsigned-binop-c)
  (:args (x :scs (signed-reg)))
  (:translate logand)
  (:arg-types signed-num
	      (:constant (or (and (unsigned-byte 15) (not (integer 0 0)))
			     (integer #xffffffff #xffffffff))))
  (:generator 2				; Needs to be low to give this vop a chance.
    (cond ((= y #xffffffff)
	   (move r x))
	  ((typep y '(unsigned-byte 15))
	   (inst andi. r x y)))))

(define-vop (fast-abs/signed fast-safe-arith-op)
  (:args (x :scs (signed-reg)))
  (:arg-types signed-num)
  (:results (r :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:translate abs)
  (:note "inline 32-bit abs")
  (:temporary (:scs (signed-reg)) y)
  (:generator 1
    ;; From Hacker's Delight
    ;;
    ;; abs(x) = (x ^ y) - y, where y = x >> 31 (signed shift)
    (inst srawi y x (1- vm:word-bits))
    (inst xor r y x)
    (inst sub r r y)))

;;; Special case fixnum + and - that trap on overflow.  Useful when we
;;; don't know that the output type is a fixnum.
;;;
#+nil
(progn
(define-vop (+/fixnum fast-+/fixnum=>fixnum)
  (:policy :safe)
  (:results (r :scs (any-reg descriptor-reg)))
  (:result-types tagged-num)
  (:note "safe inline fixnum arithmetic")
  (:generator 4
    (let* ((no-overflow (gen-label)))
      (inst mtxer zero-tn)
      (inst addo. r x y)
      (inst bns no-overflow)
      (inst unimp (logior (ash (reg-tn-encoding r) 5)
			  fixnum-additive-overflow-trap))
      (emit-label no-overflow))))


(define-vop (-/fixnum fast--/fixnum=>fixnum)
  (:policy :safe)
  (:results (r :scs (any-reg descriptor-reg)))
  (:result-types tagged-num)
  (:note "safe inline fixnum arithmetic")
  (:generator 4
    (let* ((no-overflow (gen-label)))
      (inst mtxer zero-tn)
      (inst subo. r x y)
      (inst bns no-overflow)
      (inst unimp (logior (ash (reg-tn-encoding r) 5)
			  fixnum-additive-overflow-trap))
      (emit-label no-overflow))))
)

(define-vop (fast-*/fixnum=>fixnum fast-fixnum-binop)
  (:temporary (:scs (non-descriptor-reg)) temp)
  (:translate *)
  (:generator 2
    (inst srawi temp y 2)
    (inst mullw r x temp)))

(define-vop (fast-*-c/fixnum=>fixnum fast-fixnum-binop-c)
  (:translate *)
  (:arg-types tagged-num 
	      (:constant (and (signed-byte 16) (not (integer 0 0)))))
  (:generator 1
    (inst mulli r x y)))

(define-vop (fast-*-bigc/fixnum=>fixnum fast-fixnum-binop-c)
  (:translate *)
  (:arg-types tagged-num
	      (:constant (and fixnum (not (signed-byte 16)))))
  (:temporary (:scs (non-descriptor-reg)) temp)
  (:generator 1
    (inst lr temp y)
    (inst mullw r x temp)))

(define-vop (fast-*/signed=>signed fast-signed-binop)
  (:translate *)
  (:generator 4
    (inst mullw r x y)))

(define-vop (fast-*-c/signed=>signed fast-signed-binop-c)
  (:translate *)
  (:generator 3
    (inst mulli r x y)))

(define-vop (fast-*/unsigned=>unsigned fast-unsigned-binop)
  (:translate *)
  (:generator 4
    (inst mullw r x y)))

(define-vop (fast-*-c/unsigned=>unsigned fast-unsigned-binop-c)
  (:translate *)
  (:generator 3
    (inst mulli r x y)))

;;; Shifting

(define-vop (fast-ash/unsigned=>unsigned)
  (:note "inline ASH")
  (:args (number :scs (unsigned-reg) :to :save)
	 (amount :scs (signed-reg immediate)))
  (:arg-types (:or 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 3
    (sc-case amount
      (signed-reg
       (let ((positive (gen-label))
	     (done (gen-label)))
	 (inst cmpwi amount 0)
	 (inst neg ndesc amount)
	 (inst bge positive)
	 (inst cmpwi ndesc 31)
	 (inst srw result number ndesc)
	 (inst ble done)
	 (move result zero-tn)
	 (inst b done)

	 (emit-label positive)
	 ;; The result-type assures us that this shift will not overflow.
	 (inst slw result number amount)

	 (emit-label done)))
      (immediate
       (let ((amount (tn-value amount)))
	 (cond
	  ((and (minusp amount) (< amount -31)) (move result zero-tn))
	  ((minusp amount) (inst srwi result number (- amount)))
	  ((> amount 31) (move result zero-tn))
	  (t (inst slwi result number amount))))))))

(define-vop (fast-ash/signed=>signed)
  (:note "inline ASH")
  (:args (number :scs (signed-reg) :to :save)
	 (amount :scs (signed-reg immediate)))
  (:arg-types (:or signed-num) signed-num)
  (:results (result :scs (signed-reg)))
  (:result-types (:or signed-num))
  (:translate ash)
  (:policy :fast-safe)
  (:temporary (:sc non-descriptor-reg) ndesc)
  (:generator 3
    (sc-case amount
      (signed-reg
       (let ((positive (gen-label))
	     (done (gen-label)))
	 (inst cmpwi amount 0)
	 (inst neg ndesc amount)
	 (inst bge positive)
	 (inst cmpwi ndesc 31)
	 (inst sraw result number ndesc)
	 (inst ble done)
	 (inst srawi result number 31)
	 (inst b done)

	 (emit-label positive)
	 ;; The result-type assures us that this shift will not overflow.
	 (inst slw result number amount)

	 (emit-label done)))

      (immediate
       (let ((amount (tn-value amount)))
	 (if (minusp amount)
	     (let ((amount (min 31 (- amount))))
	       (inst srawi result number amount))
	     (inst slwi result number amount)))))))



(define-vop (signed-byte-32-len)
  (:translate integer-length)
  (:note "inline (signed-byte 32) integer-length")
  (:policy :fast-safe)
  (:args (arg :scs (signed-reg)))
  (:arg-types signed-num)
  (:results (res :scs (any-reg)))
  (:result-types positive-fixnum)
  (:temporary (:scs (non-descriptor-reg) :to (:argument 0)) shift)
  (:generator 6
    ; (integer-length arg) = (- 32 (cntlz (if (>= arg 0) arg (lognot arg))))
    (let ((nonneg (gen-label)))
      (inst cntlzw. shift arg)
      (inst bne nonneg)
      (inst not shift arg)
      (inst cntlzw shift shift)
      (emit-label nonneg)
      (inst slwi shift shift 2)
      (inst subfic res  shift (fixnumize 32)))))

(define-vop (unsigned-byte-32-len)
  (:translate integer-length)
  (:note "inline (unsigned-byte 32) integer-length")
  (:policy :fast-safe)
  (:args (arg :scs (unsigned-reg)))
  (:arg-types unsigned-num)
  (:results (res :scs (any-reg)))
  (:result-types positive-fixnum)
  (:temporary (:scs (non-descriptor-reg) :to (:argument 0)) shift)
  (:generator 6
    ; (integer-length arg) = (- 32 (cntlz arg)))
    (inst cntlzw shift arg)
    (inst slwi shift shift 2)
    (inst subfic res  shift (fixnumize 32))))

#+nil
(define-vop (unsigned-byte-32-count)
  (:translate logcount)
  (:note "inline (unsigned-byte 32) logcount")
  (:policy :fast-safe)
  (:args (arg :scs (unsigned-reg) :target shift))
  (:arg-types unsigned-num)
  (:results (res :scs (any-reg)))
  (:result-types positive-fixnum)
  (:temporary (:scs (non-descriptor-reg) :from (:argument 0)) shift temp)
  (:generator 30
    (let ((loop (gen-label))
	  (done (gen-label)))
      (inst add. shift zero-tn arg)
      (move res zero-tn)
      (inst beq done)

      (emit-label loop)
      (inst subi temp shift 1)
      (inst and. shift shift temp)
      (inst addi res res (fixnumize 1))
      (inst bne loop)

      (emit-label done))))

(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 lr mask bit-mask)

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


;;;; Binary conditional VOPs:

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

(deftype integer-with-a-bite-out (s bite)
  (cond ((eq s '*) 'integer)
	((and (integerp s) (> s 1))
	 (let ((bound (ash 1 (1- s))))
	   `(integer ,(- bound) ,(- bound bite 1))))
	(t
	 (error "Bad size specified for SIGNED-BYTE type specifier: ~S." s))))

(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 14)))
  (: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 16)))
  (: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 16)))
  (:info target not-p y))


(define-vop (fast-if-</fixnum fast-conditional/fixnum)
  (:translate <)
  (:generator 4
    (inst cmpw x y)
    (inst b? (if not-p :ge :lt) target)))

(define-vop (fast-if-<-c/fixnum fast-conditional-c/fixnum)
  (:translate <)
  (:generator 3
    (inst cmpwi x (fixnumize y))
    (inst b? (if not-p :ge :lt) target)))

(define-vop (fast-if-</signed fast-conditional/signed)
  (:translate <)
  (:generator 6
    (inst cmpw x y)
    (inst b? (if not-p :ge :lt) target)))

(define-vop (fast-if-<-c/signed fast-conditional-c/signed)
  (:translate <)
  (:generator 5
    (inst cmpwi x y)
    (inst b? (if not-p :ge :lt) target)))

(define-vop (fast-if-</unsigned fast-conditional/unsigned)
  (:translate <)
  (:generator 6
    (inst cmplw x y)
    (inst b? (if not-p :ge :lt) target)))

(define-vop (fast-if-<-c/unsigned fast-conditional-c/unsigned)
  (:translate <)
  (:generator 5
    (inst cmplwi x y)
    (inst b? (if not-p :ge :lt) target)))

(define-vop (fast-if->/fixnum fast-conditional/fixnum)
  (:translate >)
  (:generator 4
    (inst cmpw x y)
    (inst b? (if not-p :le :gt) target)))

(define-vop (fast-if->-c/fixnum fast-conditional-c/fixnum)
  (:translate >)
  (:generator 3
    (inst cmpwi x (fixnumize y))
    (inst b? (if not-p :le :gt) target)))

(define-vop (fast-if->/signed fast-conditional/signed)
  (:translate >)
  (:generator 6
    (inst cmpw x y)
    (inst b? (if not-p :le :gt) target)))

(define-vop (fast-if->-c/signed fast-conditional-c/signed)
  (:translate >)
  (:generator 5
    (inst cmpwi x y)
    (inst b? (if not-p :le :gt) target)))

(define-vop (fast-if->/unsigned fast-conditional/unsigned)
  (:translate >)
  (:generator 6
    (inst cmplw x y)
    (inst b? (if not-p :le :gt) target)))

(define-vop (fast-if->-c/unsigned fast-conditional-c/unsigned)
  (:translate >)
  (:generator 5
    (inst cmplwi x y)
    (inst b? (if not-p :le :gt) target)))

(define-vop (fast-if-eql/signed fast-conditional/signed)
  (:translate eql)
  (:generator 6
    (inst cmpw x y)
    (inst b? (if not-p :ne :eq) target)))

(define-vop (fast-if-eql-c/signed fast-conditional-c/signed)
  (:translate eql)
  (:generator 5
    (inst cmpwi x y)
    (inst b? (if not-p :ne :eq) target)))

(define-vop (fast-if-eql/unsigned fast-conditional/unsigned)
  (:translate eql)
  (:generator 6
    (inst cmplw x y)
    (inst b? (if not-p :ne :eq) target)))

(define-vop (fast-if-eql-c/unsigned fast-conditional-c/unsigned)
  (:translate eql)
  (:generator 5
    (inst cmplwi x y)
    (inst b? (if not-p :ne :eq) target)))


;;; 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 cmpw x y)
    (inst b? (if not-p :ne :eq) target)))
;;;
(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 14)))
  (:info target not-p y)
  (:translate eql)
  (:generator 2
    (inst cmpwi x (fixnumize y))
    (inst b? (if not-p :ne :eq) target)))
;;;
(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)
  (:args (shift :scs (signed-reg unsigned-reg))
	 (prev :scs (unsigned-reg))
	 (next :scs (unsigned-reg)))
  (:arg-types tagged-num unsigned-num unsigned-num)
  (:temporary (:scs (unsigned-reg) :to (:result 0)) temp)
  (:temporary (:scs (unsigned-reg) :to (:result 0) :target result) res)
  (:results (result :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:policy :fast-safe)
  (:generator 4
    (let ((done (gen-label)))
      (inst cmpwi shift 0)
      (inst beq done)
      (inst srw res next shift)
      (inst sub temp zero-tn shift)
      (inst slw temp prev temp)
      (inst or res res temp)
      (emit-label done)
      (move result res))))


(define-vop (32bit-logical)
  (:args (x :scs (unsigned-reg zero))
	 (y :scs (unsigned-reg zero)))
  (:arg-types unsigned-num unsigned-num)
  (:results (r :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:policy :fast-safe))

(define-vop (32bit-logical-not 32bit-logical)
  (:translate 32bit-logical-not)
  (:args (x :scs (unsigned-reg zero)))
  (:arg-types unsigned-num)
  (:generator 1
    (inst not r x)))

(define-vop (32bit-logical-and 32bit-logical)
  (:translate 32bit-logical-and)
  (:generator 1
    (inst and r x y)))

(deftransform 32bit-logical-nand ((x y) (* *))
  '(32bit-logical-not (32bit-logical-and x y)))

(define-vop (32bit-logical-or 32bit-logical)
  (:translate 32bit-logical-or)
  (:generator 1
    (inst or r x y)))

(deftransform 32bit-logical-nor ((x y) (* *))
  '(32bit-logical-not (32bit-logical-or x y)))

(define-vop (32bit-logical-xor 32bit-logical)
  (:translate 32bit-logical-xor)
  (:generator 1
    (inst xor r x y)))

(define-vop (32bit-logical-eqv 32bit-logical)
  (:translate 32bit-logical-eqv)
  (:generator 1
    (inst eqv r x y)))

(define-vop (32bit-logical-orc2 32bit-logical)
  (:translate 32bit-logical-orc2)
  (:generator 1
    (inst orc r x y)))

(deftransform 32bit-logical-orc1 ((x y) (* *))
  '(32bit-logical-orc2 y x))

(define-vop (32bit-logical-andc2 32bit-logical)
  (:translate 32bit-logical-andc2)
  (:generator 1
    (inst andc r x y)))

(deftransform 32bit-logical-andc1 ((x y) (* *))
  '(32bit-logical-andc2 y x))


(define-vop (shift-towards-someplace)
  (:policy :fast-safe)
  (:args (num :scs (unsigned-reg))
	 (amount :scs (signed-reg)))
  (:arg-types unsigned-num tagged-num)
  (:results (r :scs (unsigned-reg)))
  (:result-types unsigned-num))

(define-vop (shift-towards-start shift-towards-someplace)
  (:translate shift-towards-start)
  (:note "shift-towards-start")
  (:generator 1
    (inst rlwinm amount amount 0 27 31)
    (inst slw r num amount)))

(define-vop (shift-towards-end shift-towards-someplace)
  (:translate shift-towards-end)
  (:note "shift-towards-end")
  (:generator 1
    (inst rlwinm amount amount 0 27 31)
    (inst srw r num amount)))




;;;; Bignum stuff.

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

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

(define-vop (bignum-ref word-index-ref)
  (:variant vm:bignum-digits-offset vm:other-pointer-type)
  (:translate bignum::%bignum-ref)
  (:results (value :scs (unsigned-reg)))
  (:result-types unsigned-num))

(define-vop (bignum-set word-index-set)
  (:variant vm:bignum-digits-offset vm:other-pointer-type)
  (:translate bignum::%bignum-set)
  (:args (object :scs (descriptor-reg))
	 (index :scs (any-reg immediate zero))
	 (value :scs (unsigned-reg)))
  (:arg-types t positive-fixnum unsigned-num)
  (:results (result :scs (unsigned-reg)))
  (:result-types unsigned-num))

(define-vop (digit-0-or-plus)
  (:translate bignum::%digit-0-or-plusp)
  (:policy :fast-safe)
  (:args (digit :scs (unsigned-reg)))
  (:arg-types unsigned-num)
  (:results (result :scs (descriptor-reg)))
  (:generator 3
    (let ((done (gen-label)))
      (inst cmpwi digit 0)
      (move result null-tn)
      (inst blt done)
      (load-symbol result t)
      (emit-label done))))

(define-vop (add-w/carry)
  (:translate bignum::%add-with-carry)
  (:policy :fast-safe)
  (:args (a :scs (unsigned-reg))
	 (b :scs (unsigned-reg))
	 (c :scs (any-reg)))
  (:arg-types unsigned-num unsigned-num positive-fixnum)
  (:temporary (:scs (unsigned-reg)) temp)
  (:results (result :scs (unsigned-reg))
	    (carry :scs (unsigned-reg)))
  (:result-types unsigned-num positive-fixnum)
  (:generator 3
    (inst addic temp c -1)
    (inst adde result a b)
    (inst addze carry zero-tn)))

(define-vop (sub-w/borrow)
  (:translate bignum::%subtract-with-borrow)
  (:policy :fast-safe)
  (:args (a :scs (unsigned-reg))
	 (b :scs (unsigned-reg))
	 (c :scs (any-reg)))
  (:arg-types unsigned-num unsigned-num positive-fixnum)
  (:temporary (:scs (unsigned-reg)) temp)
  (:results (result :scs (unsigned-reg))
	    (borrow :scs (unsigned-reg)))
  (:result-types unsigned-num positive-fixnum)
  (:generator 4
    (inst addic temp c -1)
    (inst sube result a b)
    (inst addze borrow zero-tn)))

(define-vop (bignum-mult-and-add-3-arg)
  (:translate bignum::%multiply-and-add)
  (:policy :fast-safe)
  (:args (x :scs (unsigned-reg))
	 (y :scs (unsigned-reg))
	 (carry-in :scs (unsigned-reg) :to (:eval 1)))
  (:arg-types unsigned-num unsigned-num unsigned-num)
  (:temporary (:scs (unsigned-reg) :to (:result 0) :target hi) hi-temp)
  (:temporary (:scs (unsigned-reg) :from (:eval 0) :to (:result 1)
		    :target lo) lo-temp)
  (:results (hi :scs (unsigned-reg))
	    (lo :scs (unsigned-reg)))
  (:result-types unsigned-num unsigned-num)
  (:generator 40
    (inst mulhwu hi-temp x y)
    (inst mullw lo-temp x y)
    (inst addc lo lo-temp carry-in)
    (inst addze hi hi-temp)))

(define-vop (bignum-mult-and-add-4-arg)
  (:translate bignum::%multiply-and-add)
  (:policy :fast-safe)
  (:args (x :scs (unsigned-reg))
	 (y :scs (unsigned-reg))
	 (prev :scs (unsigned-reg) :to (:eval 1))
	 (carry-in :scs (unsigned-reg) :to (:eval 1)))
  (:arg-types unsigned-num unsigned-num unsigned-num unsigned-num)
  (:temporary (:scs (unsigned-reg) :to (:result 0) :target hi) hi-temp)
  (:temporary (:scs (unsigned-reg) :from (:eval 0) :to (:result 1)
		    :target lo) lo-temp)
  (:results (hi :scs (unsigned-reg))
	    (lo :scs (unsigned-reg)))
  (:result-types unsigned-num unsigned-num)
  (:generator 40
    (inst mulhwu hi-temp x y)
    (inst mullw lo-temp x y)
    (inst addc lo-temp lo-temp carry-in)
    (inst addze hi-temp hi-temp)
    (inst addc lo lo-temp prev)
    (inst addze hi hi-temp)))

(define-vop (bignum-mult)
  (:translate bignum::%multiply)
  (:policy :fast-safe)
  (:args (x :scs (unsigned-reg) :to (:eval 1))
	 (y :scs (unsigned-reg) :to (:eval 1)))
  (:arg-types unsigned-num unsigned-num)
  (:results (hi :scs (unsigned-reg) :from (:eval 1))
	    (lo :scs (unsigned-reg) :from (:eval 0)))
  (:result-types unsigned-num unsigned-num)
  (:generator 40
    (inst mullw lo x y)
    (inst mulhwu hi x y)))

(define-vop (bignum-lognot)
  (:translate bignum::%lognot)
  (:policy :fast-safe)
  (:args (x :scs (unsigned-reg)))
  (:arg-types unsigned-num)
  (:results (r :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:generator 1
    (inst not r x)))

(define-vop (fixnum-to-digit)
  (:translate bignum::%fixnum-to-digit)
  (:policy :fast-safe)
  (:args (fixnum :scs (any-reg)))
  (:arg-types tagged-num)
  (:results (digit :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:generator 1
    (inst srawi digit fixnum 2)))


(define-vop (bignum-floor)
  (:translate bignum::%floor)
  (:policy :fast-safe)
  (:args (num-high :scs (unsigned-reg) :target rem)
	 (num-low :scs (unsigned-reg) :target rem-low)
	 (denom :scs (unsigned-reg) :to (:eval 1)))
  (:arg-types unsigned-num unsigned-num unsigned-num)
  (:temporary (:scs (unsigned-reg) :from (:argument 1)) rem-low)
  (:temporary (:scs (unsigned-reg) :from (:eval 0)) temp)
  (:results (quo :scs (unsigned-reg) :from (:eval 0))
	    (rem :scs (unsigned-reg) :from (:argument 0)))
  (:result-types unsigned-num unsigned-num)
  (:generator 325 ; number of inst assuming targeting works.
    (move rem num-high)
    (move rem-low num-low)
    (flet ((maybe-subtract (&optional (guess temp))
	     (inst subi temp guess 1)
	     (inst and temp temp denom)
	     (inst sub rem rem temp))
	   (sltu (res x y)
	     (inst subfc res y x)
	     (inst subfe res res res)
	     (inst neg res res)))
      (sltu quo rem denom)
      (maybe-subtract quo)
      (dotimes (i 32)
	(inst slwi rem rem 1)
	(inst srwi temp rem-low 31)
	(inst or rem rem temp)
	(inst slwi rem-low rem-low 1)
	(sltu temp rem denom)
	(inst slwi quo quo 1)
	(inst or quo quo temp)
	(maybe-subtract)))
    (inst not quo quo)))

#|

(define-vop (bignum-floor)
  (:translate bignum::%floor)
  (:policy :fast-safe)
  (:args (div-high :scs (unsigned-reg) :target rem)
	 (div-low :scs (unsigned-reg) :target quo)
	 (divisor :scs (unsigned-reg)))
  (:arg-types unsigned-num unsigned-num unsigned-num)
  (:results (quo :scs (unsigned-reg) :from (:argument 1))
	    (rem :scs (unsigned-reg) :from (:argument 0)))
  (:result-types unsigned-num unsigned-num)
  (:generator 300
    (inst mtmq div-low)
    (inst div quo div-high divisor)
    (inst mfmq rem)))
|#

(define-vop (signify-digit)
  (:translate bignum::%fixnum-digit-with-correct-sign)
  (:policy :fast-safe)
  (:args (digit :scs (unsigned-reg) :target res))
  (:arg-types unsigned-num)
  (:results (res :scs (any-reg signed-reg)))
  (:result-types signed-num)
  (:generator 1
    (sc-case res
      (any-reg
       (inst slwi res digit 2))
      (signed-reg
       (move res digit)))))


(define-vop (digit-ashr)
  (:translate bignum::%ashr)
  (:policy :fast-safe)
  (:args (digit :scs (unsigned-reg))
	 (count :scs (signed-reg unsigned-reg immediate)))
  (:arg-types unsigned-num positive-fixnum)
  (:results (result :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:generator 1
    (sc-case count
      ((signed-reg unsigned-reg)
       (inst sraw result digit count))
      (immediate
       (inst srawi result digit (tn-value count))))))

(define-vop (digit-lshr digit-ashr)
  (:translate bignum::%digit-logical-shift-right)
  (:generator 1
    (sc-case count
      ((signed-reg unsigned-reg)
       (inst srw result digit count))
      (immediate
       (inst srawi result digit (tn-value count))))))

(define-vop (digit-ashl digit-ashr)
  (:translate bignum::%ashl)
  (:generator 1
    (sc-case count
      ((signed-reg unsigned-reg)
       (inst slw result digit count))
      (immediate
       (inst slwi result digit (tn-value count))))))


;;;; Static functions.

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

(define-static-function two-arg-+ (x y) :translate +)
(define-static-function two-arg-- (x y) :translate -)
(define-static-function two-arg-* (x y) :translate *)
(define-static-function two-arg-/ (x y) :translate /)

(define-static-function two-arg-< (x y) :translate <)
(define-static-function two-arg-<= (x y) :translate <=)
(define-static-function two-arg-> (x y) :translate >)
(define-static-function two-arg->= (x y) :translate >=)
(define-static-function two-arg-= (x y) :translate =)
(define-static-function two-arg-/= (x y) :translate /=)

(define-static-function %negate (x) :translate %negate)

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


;; Truncation by a constant can be done by multiplication with the
;; appropriate constant.
;;
;; See generic/vm-tran.lisp for the algorithm.

(define-vop (signed-truncate-by-mult fast-signed-binop)
  (:translate truncate)
  (:args (x :scs (signed-reg)))
  (:info y)
  (:arg-types signed-num (:constant (integer 2 #.(1- (ash 1 vm:word-bits)))))
  (:results (quo :scs (signed-reg))
            (rem :scs (signed-reg)))
  (:result-types signed-num signed-num)
  (:note "inline (signed-byte 32) arithmetic")
  (:temporary (:scs (signed-reg)) q)
  (:temporary (:scs (signed-reg)) r)
  (:temporary (:scs (signed-reg)) temp)
  (:generator 6
    (multiple-value-bind (recip shift)
        (c::find-signed-reciprocal y vm:word-bits)
      ;; Compute q = floor(M*n/2^32).  That is, the high half of the
      ;; product.
      (inst lr temp recip)
      (inst mulhw q x temp)
      ;; Adjust if the M is negative.
      (when (minusp recip)
        (inst add q q x))
      ;; Shift quotient as needed.
      (unless (zerop shift)
        (inst srawi q q shift))
      ;; Add one to quotient if X is negative.  This is done by right
      ;; shifting X to give either -1 or 0.  Then subtract this from
      ;; the quotient.  (NOTE: in the book, the sample code has this
      ;; wrong and ADDS instead of SUBTRACTS.)
      (inst srawi temp x 31)
      (inst sub q q temp)
      ;; Now compute remainder via r = x - q*d
      (cond ((typep y '(signed-byte 13))
             (inst mulli r q y))
            (t
             (inst lr temp y)
             (inst mullw r q temp)))
      (inst sub rem x r)
      (unless (location= quo q)
        (move quo q)))))

(define-vop (unsigned-truncate-by-mult fast-signed-binop)
  (:translate truncate)
  (:args (x :scs (unsigned-reg)))
  (:info y)
  (:arg-types unsigned-num (:constant (integer 2 #.(1- (ash 1 vm:word-bits)))))
  (:results (quo :scs (unsigned-reg))
            (rem :scs (unsigned-reg)))
  (:result-types unsigned-num unsigned-num)
  (:note "inline (unsigned-byte 32) arithmetic")
  (:temporary (:scs (unsigned-reg)) q)
  (:temporary (:scs (unsigned-reg)) r)
  (:temporary (:scs (unsigned-reg)) temp)
  (:generator 6
    (multiple-value-bind (recip shift overflowp)
        (c::find-unsigned-reciprocal y vm:word-bits)
      ;; q = floor(M*x/2^32)
      (inst lr temp recip)
      (inst mulhwu q x temp)
      (cond (overflowp
             ;; The complicated case.  PPC does not have a
             ;; shift-with-carry instruction, so we use second idea
             ;; given find-unsigned-reciprocal.
             (inst sub temp x q)
             (inst srwi temp temp 1)
             (inst add temp temp q)
             (inst srwi q temp (1- shift)))
            (t
             ;; The easy case
             (unless (zerop shift)
               (inst srwi q q shift))))
      ;; Compute the remainder
      (cond ((typep y '(signed-byte 16))
             (inst mulli r q y))
            (t
             (inst lr temp y)
             (inst mullw r q temp)))
      (inst sub rem x r)
      (unless (location= quo q)
        (move quo q)))))


#+modular-arith
(progn
(c::define-modular-fun lognot-mod32 (x) lognot 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)))

;; Handle (ldb (byte 32 0) (- x)).  The (- x) gets converted to
;; (%negate x), so we build modular functions for %negate.

(c::define-modular-fun %negate-mod32 (x) kernel:%negate 32)

(define-vop (%negate-mod32/unsigned=>unsigned fast-safe-arith-op)
  (:translate %negate-mod32)
  (:args (x :scs (unsigned-reg) :target res))
  (:arg-types unsigned-num)
  (:results (res :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:generator 1
    (inst neg res x)))

(define-vop (%negate-mod32/signed=>unsigned fast-safe-arith-op)
  (:translate %negate-mod32)
  (:args (x :scs (signed-reg)))
  (:arg-types signed-num)
  (:results (res :scs (unsigned-reg)))
  (:result-types unsigned-num)
  (:generator 1
    (inst neg res x)))

(defmacro define-modular-backend (fun &optional constantp derived)
  (let ((mfun-name (symbolicate fun '-mod32))
	(modvop (symbolicate 'fast- fun '-mod32/unsigned=>unsigned))
	(modcvop (symbolicate 'fast- fun '-mod32-c/unsigned=>unsigned))
	(vop (symbolicate 'fast- (or derived fun) '/unsigned=>unsigned))
	(cvop (symbolicate 'fast- (or derived fun) '-c/unsigned=>unsigned)))
    `(progn
       (c::define-modular-fun ,mfun-name (x y) ,fun 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 logxor)
(define-modular-backend logeqv)
(define-modular-backend lognand)
(define-modular-backend logandc1)
(define-modular-backend logandc2)
(define-modular-backend logorc1)
(define-modular-backend logorc2)
(define-modular-backend * t)

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

(defknown vm::ash-left-mod32 (integer (integer 0))
  (unsigned-byte 32)
  (foldable flushable movable))

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

)

(in-package :c)

#+modular-arith
(define-modular-fun-optimizer ash ((integer count) :width width)
  ;; The count needs to be (mod 32) because the Sparc shift
  ;; instruction takes the count modulo 32.  (NOTE: Should we make
  ;; this work on Ultrasparcs?  We could then use the sllx instruction
  ;; which takes the count mod 64.  Then a left shift of 32 or more
  ;; will produce 0 in the lower 32 bits of the register, which is
  ;; what we want.)
  (when (and (<= width 32)
	     (csubtypep (continuation-type count) (specifier-type '(unsigned-byte 5))))
    (cut-to-width integer width)
    'vm::ash-left-mod32))

;;; If both arguments and the result are (unsigned-byte 32), try to come up
;;; with a ``better'' multiplication using multiplier recoding.  There are two
;;; different ways the multiplier can be recoded.  The more obvious is to shift
;;; X by the correct amount for each bit set in Y and to sum the results.  But
;;; if there is a string of bits that are all set, you can add X shifted by
;;; one more then the bit position of the first set bit and subtract X shifted
;;; by the bit position of the last set bit.  We can't use this second method
;;; when the high order bit is bit 31 because shifting by 32 doesn't work
;;; too well.
;;;


(defun *-transformer (y)
  (let ((y (continuation-value y)))
    (multiple-value-bind (result adds shifts)
	(strength-reduce-constant-multiply 'x y)
      (cond
        ((c::backend-featurep '(or :sparc-v9 :sparc-v8))
	 ;; This is an approximate break-even point.  It's pretty
	 ;; rough.
	 (when (> (+ adds shifts) 9)
	   (give-up)))
	(t
	 (give-up)))
      (or result 0))))  

#+(and modular-arith (not ppc))
(deftransform * ((x y)
		 ((unsigned-byte 32) (constant-argument (unsigned-byte 32)))
		 (unsigned-byte 32))
  "recode as shifts and adds"
  (*-transformer y))

#+(and modular-arith (not ppc))
(deftransform vm::*-mod32 ((x y)
		 ((unsigned-byte 32) (constant-argument (unsigned-byte 32)))
		 (unsigned-byte 32))
  "recode as shifts and adds"
  (*-transformer y))
