Changeset 14968

Timestamp:

Sep 1, 2011, 10:08:51 PM (13 years ago)

Author:

Gary Byers

Message:

When an exception occurs and we call out to lisp, if the PC doesn't
seem to be relative to some lisp function -don't- try to pass it
as a fixnum in a single word (that can't work if the PC is high
in the address space, as it certainly can be.) Split it into two
fixnums (in the xcf.relative-pc and xcf.tra slots) instead, and
reassemble it on the lisp side.

Location:

trunk/source

Files:

• level-1/x86-trap-support.lisp (modified) (1 diff)
• lisp-kernel/x86-exceptions.c (modified) (1 diff)

trunk/source/level-1/x86-trap-support.lisp

@@ -342 +342 @@
                         (type (simple-array (unsigned-byte 8) (*)) containing-object))
         (aref containing-object (the fixnum (+ byte-offset delta))))
-      ;; xcf.relative-pc is a fixnum, but it might be negative.
-      (let* ((encoded-pc (%get-ptr xcf-ptr target::xcf.relative-pc))
-             (pc (ash (%ptr-to-int encoded-pc) (- target::fixnumshift))))
+      ;; xcf.relative-pc is a fixnum containing the high half of the
+      ;; absolute PC; xcf.ra0 is a fixnum containing the low half
+      (let* ((high-half byte-offset)
+             (low-half (%get-object xcf-ptr target::xcf.ra0))
+             (pc #+64-bit-target (dpb high-half (byte 32 32) low-half)
+                 #+32-bit-target (dpb high-half (byte 16 16) low-half)))
         (%get-unsigned-byte (%int-to-ptr pc) delta)))))
 

trunk/source/lisp-kernel/x86-exceptions.c

@@ -474 +474 @@
   } else {
     containing_uvector = lisp_nil;
-    relative_pc = abs_pc << fixnumshift;
+#if WORD_SIZE == 64
+    relative_pc = ((abs_pc >> 32) & 0xffffffff) << fixnumshift;
+    tra = (abs_pc & 0xffffffff) << fixnumshift;
+#else
+    relative_pc = ((abs_pc >> 16) & 0xffff) << fixnumshift;
+    tra = (abs_pc & 0xffff) << fixnumshift;
+#endif
   }
   push_on_lisp_stack(xp,(LispObj)(tcr->xframe->prev));