X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=contrib%2Fsb-rotate-byte%2Fcompiler.lisp;h=2d0f1954c4ae0e96705effe484218264b10150c7;hb=a7c186163e12d2c6348f8c579f74ca43872d10a9;hp=95dcf655fa39a1d8485944631b39852bbbdcf3ef;hpb=cec71f1e4e1ead387f2ea642f760e553b6053f2b;p=sbcl.git

diff --git a/contrib/sb-rotate-byte/compiler.lisp b/contrib/sb-rotate-byte/compiler.lisp
index 95dcf65..2d0f195 100644
--- a/contrib/sb-rotate-byte/compiler.lisp
+++ b/contrib/sb-rotate-byte/compiler.lisp
@@ -29,28 +29,42 @@
 (defoptimizer (%rotate-byte derive-type) ((count size posn num))
   ;; FIXME: this looks fairly unwieldy.  I'm sure it can be made
   ;; simpler, and also be made to deal with negative integers too.
-  (let ((size (sb-c::continuation-type size)))
+  (let ((size (sb-c::lvar-type size)))
     (if (numeric-type-p size)
-	(let ((size-high (numeric-type-high size))
-	      (num-type (sb-c::continuation-type num)))
-	  (if (and size-high
-		   num-type
-		   (<= size-high sb-vm:n-word-bits)
-		   (csubtypep num-type
-			      (specifier-type `(unsigned-byte ,size-high))))
+        (let ((size-high (numeric-type-high size))
+              (num-type (sb-c::lvar-type num)))
+          (if (and size-high
+                   num-type
+                   (<= size-high sb-vm:n-word-bits)
+                   (csubtypep num-type
+                              (specifier-type `(unsigned-byte ,size-high))))
               (specifier-type `(unsigned-byte ,size-high))
-	      *universal-type*))
+              *universal-type*))
         *universal-type*)))
 
 (deftransform %rotate-byte ((count size pos integer)
-			    ((constant-arg (member 0)) * * *) *)
+                            ((constant-arg (member 0)) * * *) *)
   "fold identity operation"
   'integer)
 
 (deftransform %rotate-byte ((count size pos integer)
-			    ((or (integer -31 -1) (integer 1 31))
-			     (constant-arg (member 32))
-			     (constant-arg (member 0))
-			     (unsigned-byte 32)) *)
+                            ((integer -31 31)
+                             (constant-arg (member 32))
+                             (constant-arg (member 0))
+                             (unsigned-byte 32)) *)
   "inline 32-bit rotation"
+  ;; FIXME: What happens when, as here, the two type specifiers for
+  ;; COUNT overlap?  Which gets to run first?
   '(%unsigned-32-rotate-byte count integer))
+
+;; Generic implementation for platforms that don't supply VOPs for 32-bit
+;; rotate.
+#-(or x86 ppc)
+(deftransform %unsigned-32-rotate-byte ((.count. .integer.)
+                                        ((integer -31 31)
+                                         (unsigned-byte 32)) *)
+  '(if (< .count. 0)
+       (logior (ldb (byte 32 0) (ash .integer. (+ .count. 32)))
+               (ash .integer. .count.))
+       (logior (ldb (byte 32 0) (ash .integer. .count.))
+               (ash .integer. (- .count. 32)))))