;;; prims.scm -- definitions for primitives
 ;;;
 ;;; author :  Sandra Loosemore
 ;;; date   :  9 Jun 1992
 ;;;
 ;;; WARNING!!!  This file contains Common-Lisp specific code.
 ;;;
 
 
 ;;; Helper stuff
 
 (define-integrable (is-fixnum? x)
   (lisp:typep x 'lisp:fixnum))
 
 (define-integrable (is-integer? x)
   (lisp:typep x 'lisp:integer))
 
 (define-integrable (is-single-float? x)
   (lisp:typep x 'lisp:single-float))
 
 (define-integrable (is-double-float? x)
   (lisp:typep x 'lisp:double-float))
 
 (define-syntax (the-fixnum x)
   `(lisp:the lisp:fixnum ,x))
 
 (define-syntax (the-integer x)
   `(lisp:the lisp:integer ,x))
 
 (define-syntax (the-single-float x)
   `(lisp:the lisp:single-float ,x))
 
 (define-syntax (the-double-float x)
   `(lisp:the lisp:double-float ,x))
 
 (define-syntax (make-haskell-tuple2 x y)
   `(make-tuple (box ,x) (box ,y)))
 
 ;;; Abort
 ;;; *** Should probably do something other than just signal an error.
 
 (define (prim.abort s)
   (haskell-runtime-error s))
 
 (define (haskell-string->list s)
   (if (null? s)
       '()
       (cons (integer->char (force (car s)))
 	    (haskell-string->list (force (cdr s))))))
 
 ;;; Char
 
 (define-syntax (prim.char-to-int c)
   `(the-fixnum ,c))
 
 (define-syntax (prim.int-to-char i)
   `(the-fixnum ,i))
 
 (define-syntax (prim.eq-char i1 i2)
   `(= (the-fixnum ,i1) (the-fixnum ,i2)))
 (define-syntax (prim.not-eq-char i1 i2)
   `(not (= (the-fixnum ,i1) (the-fixnum ,i2))))
 (define-syntax (prim.le-char i1 i2)
   `(<= (the-fixnum ,i1) (the-fixnum ,i2)))
 (define-syntax (prim.not-le-char i1 i2)
   `(> (the-fixnum ,i1) (the-fixnum ,i2)))
 (define-syntax (prim.not-lt-char i1 i2)
   `(>= (the-fixnum ,i1) (the-fixnum ,i2)))
 (define-syntax (prim.lt-char i1 i2)
   `(< (the-fixnum ,i1) (the-fixnum ,i2)))
 
 (define-integrable prim.max-char 255)
 
 
 ;;; Floating
 
 (define-syntax (prim.eq-float f1 f2)
   `(= (the-single-float ,f1) (the-single-float ,f2)))
 (define-syntax (prim.not-eq-float f1 f2)
   `(not (= (the-single-float ,f1) (the-single-float ,f2))))
 (define-syntax (prim.le-float f1 f2)
   `(<= (the-single-float ,f1) (the-single-float ,f2)))
 (define-syntax (prim.not-le-float f1 f2)
   `(> (the-single-float ,f1) (the-single-float ,f2)))
 (define-syntax (prim.not-lt-float f1 f2)
   `(>= (the-single-float ,f1) (the-single-float ,f2)))
 (define-syntax (prim.lt-float f1 f2)
   `(< (the-single-float ,f1) (the-single-float ,f2)))
 
 (define-syntax (prim.eq-double f1 f2)
   `(= (the-double-float ,f1) (the-double-float ,f2)))
 (define-syntax (prim.not-eq-double f1 f2)
   `(not (= (the-double-float ,f1) (the-double-float ,f2))))
 (define-syntax (prim.le-double f1 f2)
   `(<= (the-double-float ,f1) (the-double-float ,f2)))
 (define-syntax (prim.not-le-double f1 f2)
   `(> (the-double-float ,f1) (the-double-float ,f2)))
 (define-syntax (prim.not-lt-double f1 f2)
   `(>= (the-double-float ,f1) (the-double-float ,f2)))
 (define-syntax (prim.lt-double f1 f2)
   `(< (the-double-float ,f1) (the-double-float ,f2)))
 
 (define-syntax (prim.float-max f1 f2)
   `(the-single-float (max (the-single-float ,f1) (the-single-float ,f2))))
 (define-syntax (prim.float-min f1 f2)
   `(the-single-float (min (the-single-float ,f1) (the-single-float ,f2))))
 
 (define-syntax (prim.double-max f1 f2)
   `(the-double-float (max (the-double-float ,f1) (the-double-float ,f2))))
 (define-syntax (prim.double-min f1 f2)
   `(the-double-float (min (the-double-float ,f1) (the-double-float ,f2))))
 
 (define-syntax (prim.plus-float f1 f2)
   `(the-single-float (+ (the-single-float ,f1) (the-single-float ,f2))))
 (define-syntax (prim.minus-float f1 f2) 
   `(the-single-float (- (the-single-float ,f1) (the-single-float ,f2))))
 (define-syntax (prim.mul-float f1 f2)
   `(the-single-float (* (the-single-float ,f1) (the-single-float ,f2))))
 (define-syntax (prim.div-float f1 f2)
   `(the-single-float (/ (the-single-float ,f1) (the-single-float ,f2))))
 
 (define-syntax (prim.plus-double f1 f2)
   `(the-double-float (+ (the-double-float ,f1) (the-double-float ,f2))))
 (define-syntax (prim.minus-double f1 f2) 
   `(the-double-float (- (the-double-float ,f1) (the-double-float ,f2))))
 (define-syntax (prim.mul-double f1 f2)
   `(the-double-float (* (the-double-float ,f1) (the-double-float ,f2))))
 (define-syntax (prim.div-double f1 f2)
   `(the-double-float (/ (the-double-float ,f1) (the-double-float ,f2))))
 
 
 (define-syntax (prim.neg-float f)
   `(the-single-float (- (the-single-float ,f))))
 
 (define-syntax (prim.neg-double f)
   `(the-double-float (- (the-double-float ,f))))
 
 (define-syntax (prim.abs-float f)
   `(the-single-float (lisp:abs (the-single-float ,f))))
 
 (define-syntax (prim.abs-double f)
   `(the-double-float (lisp:abs (the-double-float ,f))))
 
 
 (define-syntax (prim.exp-float f)
   `(the-single-float (lisp:exp (the-single-float ,f))))
 (define-syntax (prim.log-float f)
   `(the-single-float (lisp:log (the-single-float ,f))))
 (define-syntax (prim.sqrt-float f)
   `(the-single-float (lisp:sqrt (the-single-float ,f))))
 (define-syntax (prim.sin-float f)
   `(the-single-float (lisp:sin (the-single-float ,f))))
 (define-syntax (prim.cos-float f)
   `(the-single-float (lisp:cos (the-single-float ,f))))
 (define-syntax (prim.tan-float f)
   `(the-single-float (lisp:tan (the-single-float ,f))))
 (define-syntax (prim.asin-float f)
   `(the-single-float (lisp:asin (the-single-float ,f))))
 (define-syntax (prim.acos-float f)
   `(the-single-float (lisp:acos (the-single-float ,f))))
 (define-syntax (prim.atan-float f)
   `(the-single-float (lisp:atan (the-single-float ,f))))
 (define-syntax (prim.sinh-float f)
   `(the-single-float (lisp:sinh (the-single-float ,f))))
 (define-syntax (prim.cosh-float f)
   `(the-single-float (lisp:cosh (the-single-float ,f))))
 (define-syntax (prim.tanh-float f)
   `(the-single-float (lisp:tanh (the-single-float ,f))))
 (define-syntax (prim.asinh-float f)
   `(the-single-float (lisp:asinh (the-single-float ,f))))
 (define-syntax (prim.acosh-float f)
   `(the-single-float (lisp:acosh (the-single-float ,f))))
 (define-syntax (prim.atanh-float f)
   `(the-single-float (lisp:atanh (the-single-float ,f))))
 
 
 (define-syntax (prim.exp-double f)
   `(the-double-float (lisp:exp (the-double-float ,f))))
 (define-syntax (prim.log-double f)
   `(the-double-float (lisp:log (the-double-float ,f))))
 (define-syntax (prim.sqrt-double f)
   `(the-double-float (lisp:sqrt (the-double-float ,f))))
 (define-syntax (prim.sin-double f)
   `(the-double-float (lisp:sin (the-double-float ,f))))
 (define-syntax (prim.cos-double f)
   `(the-double-float (lisp:cos (the-double-float ,f))))
 (define-syntax (prim.tan-double f)
   `(the-double-float (lisp:tan (the-double-float ,f))))
 (define-syntax (prim.asin-double f)
   `(the-double-float (lisp:asin (the-double-float ,f))))
 (define-syntax (prim.acos-double f)
   `(the-double-float (lisp:acos (the-double-float ,f))))
 (define-syntax (prim.atan-double f)
   `(the-double-float (lisp:atan (the-double-float ,f))))
 (define-syntax (prim.sinh-double f)
   `(the-double-float (lisp:sinh (the-double-float ,f))))
 (define-syntax (prim.cosh-double f)
   `(the-double-float (lisp:cosh (the-double-float ,f))))
 (define-syntax (prim.tanh-double f)
   `(the-double-float (lisp:tanh (the-double-float ,f))))
 (define-syntax (prim.asinh-double f)
   `(the-double-float (lisp:asinh (the-double-float ,f))))
 (define-syntax (prim.acosh-double f)
   `(the-double-float (lisp:acosh (the-double-float ,f))))
 (define-syntax (prim.atanh-double f)
   `(the-double-float (lisp:atanh (the-double-float ,f))))
 
 
 (define-integrable prim.pi-float (lisp:coerce lisp:pi 'lisp:single-float))
 
 (define-integrable prim.pi-double (lisp:coerce lisp:pi 'lisp:double-float))
 
 
 ;;; Assumes rationals are represented as a 2-tuple of integers
 
 (define (prim.rational-to-float x)
   (let ((n (tuple-select 2 0 x))
 	(d (tuple-select 2 1 x)))
     (if (eqv? d 0)
 	(haskell-runtime-error "Divide by 0.")
 	(prim.rational-to-float-aux n d))))
 
 (define (prim.rational-to-float-aux n d)
   (declare (type integer n d))
   (/ (lisp:coerce n 'lisp:single-float)
      (lisp:coerce d 'lisp:single-float)))
 
 (define (prim.rational-to-double x)
   (let ((n (tuple-select 2 0 x))
 	(d (tuple-select 2 1 x)))
     (if (eqv? d 0)
 	(haskell-runtime-error "Divide by 0.")
 	(prim.rational-to-double-aux n d))))
 
 (define (prim.rational-to-double-aux n d)
   (declare (type integer n d))
   (/ (lisp:coerce n 'lisp:double-float)
      (lisp:coerce d 'lisp:double-float)))
 
 (define (prim.float-to-rational x)
   (let ((r  (lisp:rational (the lisp:single-float x))))
     (declare (type rational r))
     (make-tuple (lisp:numerator r) (lisp:denominator r))))
 
 (define (prim.double-to-rational x)
   (let ((r  (lisp:rational (the lisp:double-float x))))
     (declare (type rational r))
     (make-tuple (lisp:numerator r) (lisp:denominator r))))
 
 
 (define-integrable prim.float-1 (lisp:coerce 1.0 'lisp:single-float))
 (define-integrable prim.double-1 (lisp:coerce 1.0 'lisp:double-float))
 
 (define-integrable prim.float-digits
   (lisp:float-digits prim.float-1))
 
 (define-integrable prim.double-digits
   (lisp:float-digits prim.double-1))
 
 (define-integrable prim.float-radix
   (lisp:float-radix prim.float-1))
 
 (define-integrable prim.double-radix
   (lisp:float-radix prim.double-1))
 
 
 ;;; Sometimes least-positive-xxx-float is denormalized.
 
 (define-integrable prim.float-min-exp
   (multiple-value-bind (m e)
       (lisp:decode-float
         #+lucid lcl:least-positive-normalized-single-float
 	#-lucid lisp:least-positive-single-float)
     (declare (ignore m))
     e))
 
 (define-integrable prim.double-min-exp
   (multiple-value-bind (m e)
       (lisp:decode-float
         #+lucid lcl:least-positive-normalized-double-float
 	#-lucid lisp:least-positive-double-float)
     (declare (ignore m))
     e))
 
 (define-integrable prim.float-max-exp
   (multiple-value-bind (m e)
       (lisp:decode-float lisp:most-positive-single-float)
     (declare (ignore m))
     e))
 
 (define-integrable prim.double-max-exp
   (multiple-value-bind (m e)
       (lisp:decode-float lisp:most-positive-double-float)
     (declare (ignore m))
     e))
 
 (define-integrable (prim.float-range x)
   (declare (ignore x))
   (make-haskell-tuple2 prim.float-min-exp prim.float-max-exp))
 
 (define-integrable (prim.double-range x)
   (declare (ignore x))
   (make-haskell-tuple2 prim.double-min-exp prim.double-max-exp))
 
 
 ;;; *** I'm not sure if these are correct.  Should the exponent value
 ;;; *** be taken as the value that lisp:integer-decode-float returns,
 ;;; *** or as the value that lisp:decode-float returns?  (They're
 ;;; *** not the same because the significand is scaled differently.)
 ;;; *** I'm guessing that Haskell's model is to use the actual numbers
 ;;; *** that are in the bit fields 
 
 ;;; jcp - I removed this since Haskell requires an integer instead of a
 ;;; fractional mantissa.  My theory is that integer-decode-float returns
 ;;; what Haskell wants without fiddling (except sign reattachment)
 
 (define (exponent-adjustment m)
   (if (eqv? prim.float-radix 2)
       ;; the usual case -- e.g. IEEE floating point
       (lisp:integer-length m)
       (lisp:ceiling (lisp:log m prim.float-radix))))
 
 (define (prim.decode-float f)
   (multiple-value-bind (m e s)
       (lisp:integer-decode-float (the-single-float f))
     (make-haskell-tuple2 (* (the-integer m) (the-fixnum s))
 			 (the-fixnum e))))
 
 (define (prim.decode-double f)
   (multiple-value-bind (m e s)
       (lisp:integer-decode-float (the-double-float f))
     (make-haskell-tuple2 (* (the-integer m) (the-fixnum s))
 			 (the-fixnum e))))
 
 (define (prim.encode-float m e)
   (lisp:scale-float (lisp:coerce m 'lisp:single-float) (the-fixnum e)))
 
 (define (prim.encode-double m e)
   (lisp:scale-float (lisp:coerce m 'lisp:double-float) (the-fixnum e)))
 
 
 ;;; Integral
 
 (define-syntax (prim.eq-int i1 i2)
   `(= (the-fixnum ,i1) (the-fixnum ,i2)))
 (define-syntax (prim.not-eq-int i1 i2)
   `(not (= (the-fixnum ,i1) (the-fixnum ,i2))))
 (define-syntax (prim.le-int i1 i2)
   `(<= (the-fixnum ,i1) (the-fixnum ,i2)))
 (define-syntax (prim.not-le-int i1 i2)
   `(> (the-fixnum ,i1) (the-fixnum ,i2)))
 (define-syntax (prim.not-lt-int i1 i2)
   `(>= (the-fixnum ,i1) (the-fixnum ,i2)))
 (define-syntax (prim.lt-int i1 i2)
   `(< (the-fixnum ,i1) (the-fixnum ,i2)))
 (define-syntax (prim.int-max i1 i2)
   `(the-fixnum (max (the-fixnum ,i1) (the-fixnum ,i2))))
 (define-syntax (prim.int-min i1 i2)
   `(the-fixnum (min (the-fixnum ,i1) (the-fixnum ,i2))))
 
 (define-syntax (prim.eq-integer i1 i2)
   `(= (the-integer ,i1) (the-integer ,i2)))
 (define-syntax (prim.not-eq-integer i1 i2)
   `(not (= (the-integer ,i1) (the-integer ,i2))))
 (define-syntax (prim.le-integer i1 i2)
   `(<= (the-integer ,i1) (the-integer ,i2)))
 (define-syntax (prim.not-le-integer i1 i2)
   `(> (the-integer ,i1) (the-integer ,i2)))
 (define-syntax (prim.not-lt-integer i1 i2)
   `(>= (the-integer ,i1) (the-integer ,i2)))
 (define-syntax (prim.lt-integer i1 i2)
   `(< (the-integer ,i1) (the-integer ,i2)))
 (define-syntax (prim.integer-max i1 i2)
   `(the-integer (max (the-integer ,i1) (the-integer ,i2))))
 (define-syntax (prim.integer-min i1 i2)
   `(the-integer (min (the-integer ,i1) (the-integer ,i2))))
 
 
 (define-syntax (prim.plus-int i1 i2)
   `(the-fixnum (+ (the-fixnum ,i1) (the-fixnum ,i2))))
 (define-syntax (prim.minus-int i1 i2)
   `(the-fixnum (- (the-fixnum ,i1) (the-fixnum ,i2))))
 (define-syntax (prim.mul-int i1 i2)
   `(the-fixnum (* (the-fixnum ,i1) (the-fixnum ,i2))))
 (define-syntax (prim.neg-int i)
   `(the-fixnum (- (the-fixnum ,i))))
 (define-syntax (prim.abs-int i)
   `(the-fixnum (lisp:abs (the-fixnum ,i))))
 
 (define-integrable prim.minint lisp:most-negative-fixnum)
 (define-integrable prim.maxint lisp:most-positive-fixnum)
 
 (define-syntax (prim.plus-integer i1 i2)
   `(the-integer (+ (the-integer ,i1) (the-integer ,i2))))
 (define-syntax (prim.minus-integer i1 i2)
   `(the-integer (- (the-integer ,i1) (the-integer ,i2))))
 (define-syntax (prim.mul-integer i1 i2)
   `(the-integer (* (the-integer ,i1) (the-integer ,i2))))
 (define-syntax (prim.neg-integer i)
   `(the-integer (- (the-integer ,i))))
 (define-syntax (prim.abs-integer i)
   `(the-integer (lisp:abs (the-integer ,i))))
 
 
 (define (prim.div-rem-int i1 i2)
   (multiple-value-bind (q r)
       (lisp:truncate (the-fixnum i1) (the-fixnum i2))
     (make-tuple (box (the-fixnum q)) (box (the-fixnum r)))))
 
 (define (prim.div-rem-integer i1 i2)
   (multiple-value-bind (q r)
       (lisp:truncate (the-integer i1) (the-integer i2))
     (make-tuple (box (the-integer q)) (box (the-integer r)))))
 
 (define (prim.integer-to-int i)
   (if (is-fixnum? i)
       (the-fixnum i)
       (haskell-runtime-error "Integer -> Int overflow.")))
 
 (define-syntax (prim.int-to-integer i)
   i)
 
 ;;; Binary
 
 (define prim.nullbin '())
 
 (define (prim.is-null-bin x)
   (null? x))
 
 (define (prim.show-bin-int i b)
   (cons i b))
 
 (define (prim.show-bin-integer i b)
   (cons i b))
 
 (define (prim.show-bin-float f b)
   (cons f b))
 
 (define (prim.show-bin-double f b)
   (cons f b))
 
 (define (prim.bin-read-error)
   (haskell-runtime-error "Error: attempt to read from an incompatible Bin."))
 
 (define (prim.read-bin-int b)
   (if (or (null? b) (not (is-fixnum? (car b))))
       (prim.bin-read-error)
       (make-haskell-tuple2 (car b) (cdr b))))
 
 (define (prim.read-bin-integer b)
   (if (or (null? b) (not (is-integer? (car b))))
       (prim.bin-read-error)
       (make-haskell-tuple2 (car b) (cdr b))))
 
 (define (prim.read-bin-float b)
   (if (or (null? b) (not (is-single-float? (car b))))
       (prim.bin-read-error)
       (make-haskell-tuple2 (car b) (cdr b))))
 
 (define (prim.read-bin-double b)
   (if (or (null? b) (not (is-double-float? (car b))))
       (prim.bin-read-error)
       (make-haskell-tuple2 (car b) (cdr b))))
 
 (define (prim.read-bin-small-int b m)
   (if (or (null? b)
 	  (not (is-fixnum? (car b)))
 	  (> (the-fixnum (car b)) (the-fixnum m)))
       (prim.bin-read-error)
       (make-haskell-tuple2 (car b) (cdr b))))
 
 (define (prim.append-bin x y)
   (append x y))
 
 
 ;;; String primitives
 
 ;;; Calls to prim.string-eq are generated by the CFN to pattern match
 ;;; against string constants.  So normally one of the arguments will be
 ;;; a constant string.  Treat this case specially to avoid consing up
 ;;; a haskell string whenever it's called.
 ;;; This function is strict in both its arguments.
 
 (define-syntax (prim.string-eq s1 s2)
   (cond ((and (pair? s1)
 	      (eq? (car s1) 'make-haskell-string))
 	 `(prim.string-eq-inline ,(cadr s1) 0 ,(string-length (cadr s1)) ,s2))
 	((and (pair? s2)
 	      (eq? (car s2) 'make-haskell-string))
 	 `(prim.string-eq-inline ,(cadr s2) 0 ,(string-length (cadr s2)) ,s1))
 	(else
 	 `(prim.string-eq-notinline ,s1 ,s2))))
 
 (define (prim.string-eq-inline lisp-string i n haskell-string)
   (declare (type fixnum i n))
   (cond ((eqv? i n)
 	 ;; Reached end of Lisp string constant -- better be at the end
 	 ;; of the Haskell string, too.
 	 (if (null? haskell-string) '#t '#f))
 	((null? haskell-string)
 	 ;; The Haskell string is too short.
 	 '#f)
 	((eqv? (the fixnum (char->integer (string-ref lisp-string i)))
 	       (the fixnum (force (car haskell-string))))
 	 ;; Next characters match, recurse
 	 (prim.string-eq-inline
 	   lisp-string (the fixnum (+ i 1)) n (force (cdr haskell-string))))
 	(else
 	 ;; No match
 	 '#f)))
 
 (define (prim.string-eq-notinline s1 s2)
   (cond ((null? s1)
 	 ;; Reached end of first string.
 	 (if (null? s2) '#t '#f))
 	((null? s2)
 	 ;; Second string too short.
 	 '#f)
 	((eqv? (the fixnum (force (car s1))) (the fixnum (force (car s2))))
 	 (prim.string-eq-notinline (force (cdr s1)) (force (cdr s2))))
 	(else
 	 '#f)))
 
   
 ;;; List primitives
 
 
 ;;; The first argument is strict and the second is a delay.
 
 (define-syntax (prim.append l1 l2)
   (cond ((and (pair? l1)
 	      (eq? (car l1) 'make-haskell-string))
 	 `(make-haskell-string-tail ,(cadr l1) ,l2))
 	((equal? l1 ''())
 	 `(force ,l2))
 	((equal? l2 '(box '()))
 	 l1)
 	;; *** could also look for
 	;; *** (append (cons x (box y)) z) => (cons x (box (append y z)))
 	;; *** but I don't think this happens very often anyway
 	(else
 	 `(prim.append-aux ,l1 ,l2))))
 
 (define (prim.append-aux l1 l2)
   (cond ((null? l1)
 	 (force l2))
 	((and (forced? l2) (eq? (unbox l2) '()))
 	 ;; Appending nil is identity.
 	 l1)
 	((forced? (cdr l1))
 	 ;; Append eagerly if the tail of the first list argument has 
          ;; already been forced.
 	 (cons (car l1)
 	       (if (null? (unbox (cdr l1)))
 		   l2  ; don't force this!!
 		   (box (prim.append-aux (unbox (cdr l1)) l2)))))
 	(else
 	 (cons (car l1) (delay (prim.append-aux (force (cdr l1)) l2))))
 	))
 
 
 ;;; Both arguments are forced here.  Have to be careful not to call
 ;;; recursively with an argument of 0.
 ;;; *** This is no longer used.
 
 (define (prim.take n l)
   (declare (type fixnum n))
   (cond ((not (pair? l))
 	 '())
 	((eqv? n 1)
 	 ;; Only one element to take.
 	 (cons (car l) (box '())))
 	((forced? (cdr l))
 	 ;; Take eagerly if the tail of the list has already been forced.
 	 (cons (car l) (box (prim.take (- n 1) (unbox (cdr l))))))
 	(else
 	 (cons (car l) (delay (prim.take (- n 1) (force (cdr l))))))
 	))
       
 
 ;;; The optimizer gets rid of all first-order calls to these functions.
 
 (define (prim.foldr k z l)
   ;; k and z are nonstrict, l is strict
   (if (null? l)
       (force z)
       (funcall (force k)
 	       (car l)
 	       (delay (prim.foldr k z (force (cdr l)))))))
 
 (define (prim.build g)
   ;; g is strict
   (funcall g
 	   (box (function make-cons-constructor))
 	   (box '())))