0.8.0.28:

	Efficient version of WITH-RECURSIVE-LOCK
	... since the frame-pointer is lispobj aligned, we can safely
		pun it into a fixnum without fearing that we'll point
		into space.  All those SAP-INTs and MAKE-LISP-OBJs then
		compile into null moves, and no more efficiency notes.

diff --git a/src/code/thread.lisp b/src/code/thread.lisp
index 458095f..288c946 100644 (file)
--- a/src/code/thread.lisp
+++ b/src/code/thread.lisp
@@ -5,14 +5,26 @@
 (sb!xc:defmacro with-recursive-lock ((mutex) &body body)
   #!+sb-thread
   (with-unique-names (cfp)
-    `(let ((,cfp (ash (sb!sys:sap-int (sb!vm::current-fp) ) -2)))
+    `(let ((,cfp (sb!kernel:current-fp)))
       (unless (and (mutex-value ,mutex)
-                  (SB!DI::control-stack-pointer-valid-p
-                   (sb!sys:int-sap (ash (mutex-value ,mutex) 2))))
-       (get-mutex ,mutex ,cfp))
+                  (sb!vm:control-stack-pointer-valid-p
+                   (sb!sys:int-sap
+                    (sb!kernel:get-lisp-obj-address (mutex-value ,mutex)))))
+       ;; this punning with MAKE-LISP-OBJ depends for its safety on
+       ;; the frame pointer being a lispobj-aligned integer.  While
+       ;; it is, then MAKE-LISP-OBJ will always return a FIXNUM, so
+       ;; we're safe to do that.  Should this ever change, than
+       ;; MAKE-LISP-OBJ could return something that looks like a
+       ;; pointer, but pointing into neverneverland, which will
+       ;; confuse GC compiletely.  -- CSR, 2003-06-03
+       (get-mutex ,mutex (sb!kernel:make-lisp-obj (sb!sys:sap-int ,cfp))))
       (unwind-protect
           (progn ,@body)
-       (when (eql (mutex-value ,mutex) ,cfp) (release-mutex ,mutex)))))
+       (when (sb!sys:sap= (sb!sys:int-sap
+                           (sb!kernel:get-lisp-obj-address
+                            (mutex-value ,mutex)))
+                          ,cfp)
+         (release-mutex ,mutex)))))
   #!-sb-thread
   `(progn ,@body))
 

diff --git a/version.lisp-expr b/version.lisp-expr
index c947453..5cec751 100644 (file)
--- a/version.lisp-expr
+++ b/version.lisp-expr
@@ -17,4 +17,4 @@
 ;;; checkins which aren't released. (And occasionally for internal
 ;;; versions, especially for internal versions off the main CVS
 ;;; branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)
-"0.8.0.27"
+"0.8.0.28"