[Sbcl-commits] CVS: sbcl/src/compiler/generic objdef.lisp, 1.63, 1.64

[Nikodemus S. <de...@us...>]

Update of /cvsroot/sbcl/sbcl/src/compiler/generic
In directory fdv4jf1.ch3.sourceforge.com:/tmp/cvs-serv31092/src/compiler/generic

Modified Files:
	objdef.lisp 
Log Message:
1.0.28.30: DEFGLOBAL, ALWAYS-BOUND, GLOBAL, SYMBOL-GLOBAL-VALUE

 * ALWAYS-BOUND allows the compiler to elide boundness checks
   for symbol value access, and prohibits MAKUNBOUND. This is
   handled via a new globaldb entry.

   GLOBAL makes the compiler elide TLS checking for symbol
   values access, and prohibits rebinding. This is handled via
   new globaldb :variable :type, namely :global.

   DEFGLOBAL is build on top of these. Global variables are mainly an
   efficiency measure on threaded builds, but can also express
   intention as they prohibit rebinding.

 * Add %SET-SYMBOL-GLOBAL-VALUE, FAST-SYMBOL-GLOBAL-VALUE, and
   SYMBOL-GLOBAL-VALUE VOPs to all backends. On unithreaded
   builds these are trivial copies of the non-global versions.

 * Tell SB-CLTL2 about both GLOBAL and ALWAYS-BOUND declarations too.

 * Document in the Efficiency chapter of the manual.

 * Prohibit declaring constants special.

 * Tests.

  Later: use these new features inside SBCL itself. For now there is
  only a single DEFGLOBAL used, but more could well be.


Index: objdef.lisp
===================================================================
RCS file: /cvsroot/sbcl/sbcl/src/compiler/generic/objdef.lisp,v
retrieving revision 1.63
retrieving revision 1.64
diff -u -d -r1.63 -r1.64
--- objdef.lisp	7 May 2009 11:11:05 -0000	1.63
+++ objdef.lisp	8 May 2009 19:08:08 -0000	1.64
@@ -322,7 +322,9 @@
   ;; first data slot, and if you subtract 7 you get a symbol header.
 
   ;; also the CAR of NIL-as-end-of-list
-  (value :init :unbound :ref-known (flushable) :ref-trans symbol-global-value)
+  (value :init :unbound
+         :set-trans %set-symbol-global-value
+         :set-known (unsafe))
   ;; also the CDR of NIL-as-end-of-list.  Its reffer needs special
   ;; care for this reason, as hash values must be fixnums.
   (hash :set-trans %set-symbol-hash)