X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=contrib%2Fsb-rotate-byte%2Fcompiler.lisp;h=38079fb1b02e09779254e050231f51c498d62f93;hb=203e2acb585b1c13159bbd6ec83c61ad9c095818;hp=2e7d5e1d7f1bc179613d2cab5aab069bc57458c5;hpb=4898ef32c639b1c7f4ee13a5ba566ce6debd03e6;p=sbcl.git

diff --git a/contrib/sb-rotate-byte/compiler.lisp b/contrib/sb-rotate-byte/compiler.lisp
index 2e7d5e1..38079fb 100644
--- a/contrib/sb-rotate-byte/compiler.lisp
+++ b/contrib/sb-rotate-byte/compiler.lisp
@@ -1,12 +1,20 @@
 (in-package "SB-ROTATE-BYTE")
 
 (defknown rotate-byte (integer byte-specifier integer) integer
-  (foldable flushable))
+  (foldable flushable)
+  :overwrite-fndb-silently t)
 (defknown %rotate-byte (integer bit-index bit-index integer) integer
-  (foldable flushable))
+  (foldable flushable)
+  :overwrite-fndb-silently t)
 (defknown %unsigned-32-rotate-byte ((integer -31 31) (unsigned-byte 32))
     (unsigned-byte 32)
-  (foldable flushable))
+  (foldable flushable)
+  :overwrite-fndb-silently t)
+#+x86-64
+(defknown %unsigned-64-rotate-byte ((integer -63 63) (unsigned-byte 64))
+    (unsigned-byte 64)
+  (foldable flushable)
+  :overwrite-fndb-silently t)
 
 (macrolet (;; see src/compiler/srctran.lisp
            (with-byte-specifier ((size-var pos-var spec) &body body)
@@ -43,16 +51,38 @@
         *universal-type*)))
 
 (deftransform %rotate-byte ((count size pos integer)
-                            ((constant-arg (member 0)) * * *) *)
-  "fold identity operation"
-  'integer)
-
-(deftransform %rotate-byte ((count size pos integer)
                             ((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 x86-64 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)))))
+
+#+x86-64
+(deftransform %rotate-byte ((count size pos integer)
+                            ((integer -63 63)
+                             (constant-arg (member 64))
+                             (constant-arg (member 0))
+                             (unsigned-byte 64)) *)
+  "inline 64-bit rotation"
+  '(%unsigned-64-rotate-byte count integer))
+
+;;; This transform needs to come after the others to ensure it gets
+;;; first crack at a zero COUNT, since transforms are currently run
+;;; latest-defined first.
+(deftransform %rotate-byte ((count size pos integer)
+                            ((constant-arg (member 0)) * * *) *)
+  "fold identity operation"
+  'integer)