0.8.12.35:

[sbcl.git] / src / code / target-sxhash.lisp

diff --git a/src/code/target-sxhash.lisp b/src/code/target-sxhash.lisp
index 99e0830..38422a1 100644 (file)
--- a/src/code/target-sxhash.lisp
+++ b/src/code/target-sxhash.lisp
@@ -36,9 +36,10 @@
 ;;;   * We'd like this to be simple and fast, too.
 ;;;
 ;;; FIXME: Should this be INLINE?
-(declaim (ftype (function ((and fixnum unsigned-byte)
-                          (and fixnum unsigned-byte))
-                         (and fixnum unsigned-byte)) mix))
+(declaim (ftype (sfunction ((and fixnum unsigned-byte)
+                            (and fixnum unsigned-byte))
+                           (and fixnum unsigned-byte))
+                mix))
 (defun mix (x y)
   ;; FIXME: We wouldn't need the nasty (SAFETY 0) here if the compiler
   ;; were smarter about optimizing ASH. (Without the THE FIXNUM below,
@@ -89,7 +90,7 @@
   (declare (type string string))
   (declare (type index count))
   (let ((result 0))
-    (declare (type (unsigned-byte 32) result))    
+    (declare (type (unsigned-byte 32) result))
     (unless (typep string '(vector nil))
       (dotimes (i count)
        (declare (type index i))
@@ -144,6 +145,12 @@
 \f
 ;;;; the SXHASH function
 
+;; simple cases
+(declaim (ftype (sfunction (integer) (integer 0 #.sb!xc:most-positive-fixnum))
+                sxhash-bignum))
+(declaim (ftype (sfunction (t) (integer 0 #.sb!xc:most-positive-fixnum))
+                sxhash-instance))
+
 (defun sxhash (x)
   ;; profiling SXHASH is hard, but we might as well try to make it go
   ;; fast, in case it is the bottleneck somwhere.  -- CSR, 2003-03-14
@@ -168,11 +175,19 @@
           (sxhash-recurse (x &optional (depthoid +max-hash-depthoid+))
             (declare (type index depthoid))
             (typecase x
-              (cons
-               (if (plusp depthoid)
-                   (mix (sxhash-recurse (car x) (1- depthoid))
-                        (sxhash-recurse (cdr x) (1- depthoid)))
-                   261835505))
+              ;; we test for LIST here, rather than CONS, because the
+              ;; type test for CONS is in fact the test for
+              ;; LIST-POINTER-LOWTAG followed by a negated test for
+              ;; NIL.  If we're going to have to test for NIL anyway,
+              ;; we might as well do it explicitly and pick off the
+              ;; answer.  -- CSR, 2004-07-14
+              (list
+               (if (null x)
+                   (sxhash x) ; through DEFTRANSFORM
+                   (if (plusp depthoid)
+                       (mix (sxhash-recurse (car x) (1- depthoid))
+                            (sxhash-recurse (cdr x) (1- depthoid)))
+                       261835505)))
               (instance
                (if (or (typep x 'structure-object) (typep x 'condition))
                    (logxor 422371266