[Sbcl-commits] CVS: sbcl/src/compiler/x86-64 c-call.lisp,1.14,1.15 parms.lisp,1.16,1.17

[Juho S. <js...@us...>]

Update of /cvsroot/sbcl/sbcl/src/compiler/x86-64
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv26649/src/compiler/x86-64

Modified Files:
	c-call.lisp parms.lisp 
Log Message:
0.9.8.14:
        Fix saving a core with callbacks on x86 and x86-64, as
        discussed on sbcl-devel "CFFI Callbacks on SBCL" on
        2005-12-31. Essentially the problem is that the address of
        #'ENTER-ALIEN-CALLBACK is hard-coded into the assembly callback
        wrappers, and the address of the function can change when
        saving a non-purified core.
        
        * Define a static symbol that contains #'ENTER-ALIEN-CALLBACK
          in the value slot.
        * Change the x86 / x86-64 wrappers to indirect through the
          slot.
        * Add minimal test case
        * Add a make-config.sh-detected :alien-callbacks feature


Index: c-call.lisp
===================================================================
RCS file: /cvsroot/sbcl/sbcl/src/compiler/x86-64/c-call.lisp,v
retrieving revision 1.14
retrieving revision 1.15
diff -u -d -r1.14 -r1.15
--- c-call.lisp	1 Dec 2005 04:16:00 -0000	1.14
+++ c-call.lisp	6 Jan 2006 01:11:10 -0000	1.15
@@ -408,7 +408,15 @@
                    (bug "Unknown alien floating point type: ~S" type)))))
 
         ;; arg0 to FUNCALL3 (function)
-        (inst mov rdi (get-lisp-obj-address #'enter-alien-callback))
+        ;;
+        ;; Indirect the access to ENTER-ALIEN-CALLBACK through
+        ;; the symbol-value slot of SB-ALIEN::*ENTER-ALIEN-CALLBACK*
+        ;; to ensure it'll work even if the GC moves ENTER-ALIEN-CALLBACK.
+        ;; Skip any SB-THREAD TLS magic, since we don't expecte anyone
+        ;; to rebind the variable. -- JES, 2006-01-01
+        (inst mov rdi (+ nil-value (static-symbol-offset
+                                    'sb!alien::*enter-alien-callback*)))
+        (loadw rdi rdi symbol-value-slot other-pointer-lowtag)
         ;; arg0 to ENTER-ALIEN-CALLBACK (trampoline index)
         (inst mov rsi (fixnumize index))
         ;; arg1 to ENTER-ALIEN-CALLBACK (pointer to argument vector)

Index: parms.lisp
===================================================================
RCS file: /cvsroot/sbcl/sbcl/src/compiler/x86-64/parms.lisp,v
retrieving revision 1.16
retrieving revision 1.17
diff -u -d -r1.16 -r1.17
--- parms.lisp	14 Dec 2005 03:39:23 -0000	1.16
+++ parms.lisp	6 Jan 2006 01:11:10 -0000	1.17
@@ -225,6 +225,10 @@
     ;; For GC-AND-SAVE
     *restart-lisp-function*
 
+    ;; Needed for callbacks to work across saving cores. see
+    ;; ALIEN-CALLBACK-ASSEMBLER-WRAPPER in c-call.lisp for gory details.
+    sb!alien::*enter-alien-callback*
+
     ;; The ..SLOT-UNBOUND.. symbol is static in order to optimise the
     ;; common slot unbound check.
     ;;