Fix setup of RD when dispatching to function headers after exit.

src/lj_trace.c

@@ -716,6 +716,8 @@ int LJ_FASTCALL lj_trace_exit(jit_State *J, void *exptr)
   case BC_TSETM:
     return (int)((BCReg)(L->top - L->base) + 1 - bc_a(*pc));
   default:
+    if (bc_op(*pc) >= BC_FUNCF)
+      return (int)((BCReg)(L->top - L->base) + 1);
     return 0;
   }
 }