X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fgeneric%2Fvm-tran.lisp;h=672b1a20b856a9e05a1d32eb4f5b711b12cfd73b;hb=b19093fa94d6e1785abee99c35c9a610e8777671;hp=a78cf36fb6a8f4b4b8c708988f393e65bcb88ea7;hpb=b1de52969f584c63d43fb35da4a8a6a4e0e619f0;p=sbcl.git

diff --git a/src/compiler/generic/vm-tran.lisp b/src/compiler/generic/vm-tran.lisp
index a78cf36..672b1a2 100644
--- a/src/compiler/generic/vm-tran.lisp
+++ b/src/compiler/generic/vm-tran.lisp
@@ -247,31 +247,26 @@
 ;;;; primitive translator for BYTE-BLT
 
 (def-primitive-translator byte-blt (src src-start dst dst-start dst-end)
-  `(let ((src ,src)
-	 (src-start (* ,src-start sb!vm:byte-bits))
-	 (dst ,dst)
-	 (dst-start (* ,dst-start sb!vm:byte-bits))
-	 (dst-end (* ,dst-end sb!vm:byte-bits)))
-     (let ((length (- dst-end dst-start)))
-       (etypecase src
-	 (system-area-pointer
-	  (etypecase dst
-	    (system-area-pointer
-	     (system-area-copy src src-start dst dst-start length))
-	    ((simple-unboxed-array (*))
-	     (copy-from-system-area src src-start
-				    dst (+ dst-start ,vector-data-bit-offset)
-				    length))))
-	 ((simple-unboxed-array (*))
-	  (etypecase dst
-	    (system-area-pointer
-	     (copy-to-system-area src (+ src-start ,vector-data-bit-offset)
-				  dst dst-start
-				  length))
-	    ((simple-unboxed-array (*))
-	     (bit-bash-copy src (+ src-start ,vector-data-bit-offset)
-			    dst (+ dst-start ,vector-data-bit-offset)
-			    length))))))))
+
+  ;; new version
+  ;;
+  ;; FIXME: CMU CL had a hairier implementation of this. It had the
+  ;; small problem that it didn't work for large (>16M) values of
+  ;; SRC-START or DST-START. However, it might have been more
+  ;; efficient. In particular, I haven't checked how much the foreign
+  ;; function call costs us here. My guess is that if the overhead is
+  ;; acceptable for SQRT and COS, it's acceptable here, but this
+  ;; should probably be checked. -- WHN
+  (once-only ((dst-start dst-start))
+    `(flet ((sap (thing)
+	      (etypecase thing
+		(system-area-pointer thing)
+		((simple-unboxed-array (*)) (vector-sap thing)))))
+	 (declare (inline sap))
+	 (without-gcing
+	  (memmove (sap+ (sap ,dst) ,dst-start)
+		   (sap+ (sap ,src) ,src-start)
+		   (- ,dst-end ,dst-start))))))
 
 ;;;; transforms for EQL of floating point values