kadie@cs.uiuc.edu (Carl M. Kadie) (11/05/90)
Arggg!! It took me a day to track this bug down.
--------------------------
lucid> (bit-ior #*0110000001100101 #*0001100000000010)
#*0000000000000000
--------------------------
It seems that some of the other bit operators are
also buggy on "long" arguments.
The compiler is Lucid/Sun 3.0.0.
I hope version 4.0 fixes this. In the mean time, here is a patch that
also fixes the Lucid's "(make-random-state t)" bug:
-------------------------------------------------
;;; Lucid bug fix - Carl Kadie, 1990
(when (string= (lisp-implementation-type) "Lucid Common Lisp")
(make-random-state t) ;; initialize the random number generator
;; in Lucid that doesn't work so ...
(dotimes (i (mod (get-universal-time) 500)) (random 10))
)
(defun BIT-OP (bit-array-1 bit-array-2 table &optional result-bit-array)
"
(bit-op #*0011 #*0101 #*0001) ;=> #*0001
"
(cond ((null result-bit-array)
(setf result-bit-array
(make-array
(array-dimensions bit-array-1)
:element-type (array-element-type bit-array-1))))
((eq result-bit-array 't)
(setf result-bit-array bit-array-1)))
(assert (vectorp bit-array-1) nil
"Sorry, patch of bit-ior works only on vectors")
(dotimes (n (array-total-size bit-array-1) result-bit-array)
(setf (bit result-bit-array n)
(bit table
(+ (* 2 (bit bit-array-1 n))(bit bit-array-2 n))))
))
(compile 'bit-op)
;; This version of lisp has problems with long bit vectors, for example,
;; it says that
;; (bit-andc2 #*1111111111111111111111111 #*1111111111111101111111111)
;; ;=> #*0000000000000000000000000, but it should
;; be #*0000000000000010000000000.
;; There are also problems in BIT-IOR, and maybe other operators.
(defun BIT-AND (b1 b2 &optional ra) (bit-op b1 b2 #*0001 ra))
(defun BIT-IOR (b1 b2 &optional ra) (bit-op b1 b2 #*0111 ra))
(defun BIT-XOR (b1 b2 &optional ra) (bit-op b1 b2 #*0110 ra))
(defun BIT-EQV (b1 b2 &optional ra) (bit-op b1 b2 #*1001 ra))
(defun BIT-NAND (b1 b2 &optional ra) (bit-op b1 b2 #*1110 ra))
(defun BIT-NOR (b1 b2 &optional ra) (bit-op b1 b2 #*1000 ra))
(defun BIT-ANDC1 (b1 b2 &optional ra) (bit-op b1 b2 #*0100 ra))
(defun BIT-ANDC2 (b1 b2 &optional ra) (bit-op b1 b2 #*0010 ra))
(defun BIT-ORC1 (b1 b2 &optional ra) (bit-op b1 b2 #*1101 ra))
(defun BIT-ORC2 (b1 b2 &optional ra) (bit-op b1 b2 #*1011 ra))
)
--
Carl Kadie -- kadie@cs.uiuc.edu -- University of Illinois at Urbana-Champaign
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