0.6.12.13:

[sbcl.git] / src / compiler / generic / vm-tran.lisp

diff --git a/src/compiler/generic/vm-tran.lisp b/src/compiler/generic/vm-tran.lisp
index a78cf36..672b1a2 100644 (file)
--- 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))))))
 \f
 ;;;; transforms for EQL of floating point values