M68k switch_to

@@ -36,9 +36,12 @@
 #define switch_to(prev,next,last) do { \
   register void *_prev __asm__ ("a0") = (prev); \
   register void *_next __asm__ ("a1") = (next); \
+  register void *_last __asm__ ("d1"); \
   __asm__ __volatile__("jbsr resume" \
-		       : : "a" (_prev), "a" (_next) \
-		       : "d0", "d1", "d2", "d3", "d4", "d5", "a0", "a1"); \
+		       : "=a" (_prev), "=a" (_next), "=d" (_last) \
+		       : "0" (_prev), "1" (_next) \
+		       : "d0", "d2", "d3", "d4", "d5"); \
+  (last) = _last; \
 } while (0)