0.8.1.50

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

diff --git a/src/code/target-sxhash.lisp b/src/code/target-sxhash.lisp
index 5fb9762..74e739b 100644 (file)
--- a/src/code/target-sxhash.lisp
+++ b/src/code/target-sxhash.lisp
@@ -26,9 +26,9 @@
 ;;; desiderata:
 ;;;   * Non-commutativity keeps us from hashing e.g. #(1 5) to the
 ;;;     same value as #(5 1), and ending up in real trouble in some
 ;;; desiderata:
 ;;;   * Non-commutativity keeps us from hashing e.g. #(1 5) to the
 ;;;     same value as #(5 1), and ending up in real trouble in some

-;;;     special cases like bit vectors the way that CMUCL SXHASH 18b
+;;;     special cases like bit vectors the way that CMUCL 18b SXHASH 

 ;;;     does. (Under CMUCL 18b, SXHASH of any bit vector is 1..)
 ;;;     does. (Under CMUCL 18b, SXHASH of any bit vector is 1..)

-;;;   * We'd like to scatter our hash values the entire possible range
+;;;   * We'd like to scatter our hash values over the entire possible range

 ;;;     of values instead of hashing small or common key values (like
 ;;;     2 and NIL and #\a) to small FIXNUMs the way that the CMUCL 18b
 ;;;     SXHASH function does, again helping to avoid pathologies like
 ;;;     of values instead of hashing small or common key values (like
 ;;;     2 and NIL and #\a) to small FIXNUMs the way that the CMUCL 18b
 ;;;     SXHASH function does, again helping to avoid pathologies like

@@ -84,11 +84,12 @@
   (declare (type index count))
   (let ((result 408967240))
     (declare (type fixnum result))
   (declare (type index count))
   (let ((result 408967240))
     (declare (type fixnum result))

-    (dotimes (i count)
-      (declare (type index i))
-      (mixf result
-           (the fixnum
-                (ash (char-code (aref string i)) 5))))
+    (unless (typep string '(vector nil))
+      (dotimes (i count)
+       (declare (type index i))
+       (mixf result
+             (the fixnum
+               (ash (char-code (aref string i)) 5)))))

     result))
 ;;; test:
 ;;;   (let ((ht (make-hash-table :test 'equal)))
     result))
 ;;; test:
 ;;;   (let ((ht (make-hash-table :test 'equal)))

@@ -115,6 +116,9 @@
 ;;;; the SXHASH function
 
 (defun sxhash (x)
 ;;;; the SXHASH function
 
 (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
+  (declare (optimize speed))

   (labels ((sxhash-number (x)
             (etypecase x
               (fixnum (sxhash x))      ; through DEFTRANSFORM
   (labels ((sxhash-number (x)
             (etypecase x
               (fixnum (sxhash x))      ; through DEFTRANSFORM

@@ -135,40 +139,39 @@
           (sxhash-recurse (x &optional (depthoid +max-hash-depthoid+))
             (declare (type index depthoid))
             (typecase x
           (sxhash-recurse (x &optional (depthoid +max-hash-depthoid+))
             (declare (type index depthoid))
             (typecase x

-              (list
+              (cons

                (if (plusp depthoid)
                    (mix (sxhash-recurse (car x) (1- depthoid))
                         (sxhash-recurse (cdr x) (1- depthoid)))
                    261835505))
               (instance
                (if (plusp depthoid)
                    (mix (sxhash-recurse (car x) (1- depthoid))
                         (sxhash-recurse (cdr x) (1- depthoid)))
                    261835505))
               (instance

-               (if (typep x 'structure-object)
+               (if (or (typep x 'structure-object) (typep x 'condition))

                    (logxor 422371266
                            (sxhash ; through DEFTRANSFORM
                    (logxor 422371266
                            (sxhash ; through DEFTRANSFORM

-                            (class-name (layout-class (%instance-layout x)))))
-                   ;; Nice though it might be to return a nontrivial
-                   ;; hash value for other instances (especially
-                   ;; STANDARD-OBJECTs) there seems to be no good way
-                   ;; to do so. We can't even do the CLASS-NAME trick
-                   ;; (as used above for STRUCTURE-OBJECT) because
-                   ;; then CHANGE-CLASS would cause SXHASH values to
-                   ;; change, ouch! -- WHN recording wisdom of CSR
-                   309518995))
+                            (classoid-name
+                             (layout-classoid (%instance-layout x)))))
+                   (sxhash-instance x)))

               (symbol (sxhash x)) ; through DEFTRANSFORM
               (array
                (typecase x
                  (simple-string (sxhash x)) ; through DEFTRANSFORM
                  (string (%sxhash-substring x))
               (symbol (sxhash x)) ; through DEFTRANSFORM
               (array
                (typecase x
                  (simple-string (sxhash x)) ; through DEFTRANSFORM
                  (string (%sxhash-substring x))

-                 (bit-vector (let ((result 410823708))
-                               (declare (type fixnum result))
-                               (dotimes (i (min depthoid (length x)))
-                                 (mixf result (aref x i)))
-                               result))
+                 (simple-bit-vector (sxhash x)) ; through DEFTRANSFORM
+                 (bit-vector
+                  ;; FIXME: It must surely be possible to do better
+                  ;; than this.  The problem is that a non-SIMPLE
+                  ;; BIT-VECTOR could be displaced to another, with a
+                  ;; non-zero offset -- so that significantly more
+                  ;; work needs to be done using the %RAW-BITS
+                  ;; approach.  This will probably do for now.
+                  (sxhash-recurse (copy-seq x) depthoid))

                  (t (logxor 191020317 (sxhash (array-rank x))))))
               (character
                (logxor 72185131
                        (sxhash (char-code x)))) ; through DEFTRANSFORM
               ;; general, inefficient case of NUMBER
               (number (sxhash-number x))
                  (t (logxor 191020317 (sxhash (array-rank x))))))
               (character
                (logxor 72185131
                        (sxhash (char-code x)))) ; through DEFTRANSFORM
               ;; general, inefficient case of NUMBER
               (number (sxhash-number x))

+              (generic-function (sxhash-instance x))

               (t 42))))
     (sxhash-recurse x)))
 \f
               (t 42))))
     (sxhash-recurse x)))
 \f

@@ -193,7 +196,7 @@
     (array (array-psxhash key depthoid))
     (hash-table (hash-table-psxhash key))
     (structure-object (structure-object-psxhash key depthoid))
     (array (array-psxhash key depthoid))
     (hash-table (hash-table-psxhash key))
     (structure-object (structure-object-psxhash key depthoid))

-    (list (list-psxhash key depthoid))
+    (cons (list-psxhash key depthoid))

     (number (number-psxhash key))
     (character (sxhash (char-upcase key)))
     (t (sxhash key))))
     (number (number-psxhash key))
     (character (sxhash (char-upcase key)))
     (t (sxhash key))))

@@ -246,8 +249,8 @@
   (declare (type (integer 0 #.+max-hash-depthoid+) depthoid))
   (let* ((layout (%instance-layout key)) ; i.e. slot #0
         (length (layout-length layout))
   (declare (type (integer 0 #.+max-hash-depthoid+) depthoid))
   (let* ((layout (%instance-layout key)) ; i.e. slot #0
         (length (layout-length layout))

-        (class (layout-class layout))
-        (name (class-name class))
+        (classoid (layout-classoid layout))
+        (name (classoid-name classoid))

         (result (mix (sxhash name) (the fixnum 79867))))
     (declare (type fixnum result))
     (dotimes (i (min depthoid (1- length)))
         (result (mix (sxhash name) (the fixnum 79867))))
     (declare (type fixnum result))
     (dotimes (i (min depthoid (1- length)))

@@ -312,7 +315,7 @@
               (etypecase key
                 (single-float (frob single-float))
                 (double-float (frob double-float))
               (etypecase key
                 (single-float (frob single-float))
                 (double-float (frob double-float))

-                (short-float (frob short-float))
+                #!+long-float

                 (long-float (error "LONG-FLOAT not currently supported")))))
       (rational (if (and (<= most-negative-double-float
                             key
                 (long-float (error "LONG-FLOAT not currently supported")))))
       (rational (if (and (<= most-negative-double-float
                             key