Update of /project/movitz/cvsroot/movitz/losp/muerte In directory clnet:/tmp/cvs-serv11191 Modified Files: hash-tables.lisp Log Message: Improve slightly sxhash on longish vectors. --- /project/movitz/cvsroot/movitz/losp/muerte/hash-tables.lisp 2006/04/07 21:52:36 1.12 +++ /project/movitz/cvsroot/movitz/losp/muerte/hash-tables.lisp 2007/02/06 20:03:57 1.13 @@ -10,7 +10,7 @@ ;;;; Author: Frode Vatvedt Fjeld <frodef@acm.org> ;;;; Created at: Mon Feb 19 19:09:05 2001 ;;;; -;;;; $Id: hash-tables.lisp,v 1.12 2006/04/07 21:52:36 ffjeld Exp $ +;;;; $Id: hash-tables.lisp,v 1.13 2007/02/06 20:03:57 ffjeld Exp $ ;;;; ;;;;------------------------------------------------------------------ @@ -74,8 +74,12 @@ ,@declarations-and-body)))) (defun sxhash-subvector (vector start end &optional (limit 8)) - (let ((result 0)) - (dotimes (i (min limit (- end start))) + (let* ((length (- end start)) + (result (if (not (> length 8)) + 0 + (sxhash-limited (aref vector (- end 3)) + 1)))) + (dotimes (i (min limit length)) (incf result result) (incf result (let* ((element (aref vector (+ start i))) @@ -84,7 +88,7 @@ element-hash (* 7 element-hash))))) (ldb (byte 16 0) - (+ (* #x10ad (- end start)) + (+ (* #x10ad length) result)))) (defun sxhash-limited (object limit)