\f
;;;; utilities
-(eval-when (:compile-toplevel :load-toplevel :execute)
- (defconstant max-hash sb!xc:most-positive-fixnum))
-
;;; Code for detecting concurrent accesses to the same table from
;;; multiple threads. Only compiled in when the :SB-HASH-TABLE-DEBUG
;;; feature is enabled. The main reason for the existence of this code
(setf (,thread-slot-accessor ,hash-table) nil)))
(body-fun)))))))
-(deftype hash ()
- `(integer 0 ,max-hash))
-
-;;; FIXME: Does this always make a nonnegative FIXNUM? If so, then
-;;; explain why. If not (or if the reason it always makes a
-;;; nonnegative FIXNUM is only the accident that pointers in supported
-;;; architectures happen to be in the lower half of the address
-;;; space), then fix it.
-#!-sb-fluid (declaim (inline pointer-hash))
-(defun pointer-hash (key)
- (declare (values hash))
- (truly-the hash (%primitive sb!c:make-fixnum key)))
-
#!-sb-fluid (declaim (inline eq-hash))
(defun eq-hash (key)
(declare (values hash (member t nil)))
(ash 1 (integer-length num)))
(declaim (inline index-for-hashing))
-(defun index-for-hashing (index length)
- (declare (type index index length))
+(defun index-for-hashing (hash length)
+ (declare (type hash hash length))
;; We're using power of two tables which obviously are very
;; sensitive to the exact values of the low bits in the hash
;; value. Do a little shuffling of the value to mix the high bits in
;; there too.
- (logand (1- length)
- (+ (logxor #b11100101010001011010100111
- index)
- (ash index -6)
- (ash index -15)
- (ash index -23))))
+ (truly-the index
+ (logand (1- length)
+ (+ (logxor #b11100101010001011010100111
+ hash)
+ (ash hash -3)
+ (ash hash -12)
+ (ash hash -20)))))
\f
;;;; user-defined hash table tests