relocate most instruction routines from MachineState to Machine

src/macros.rs

@@ -778,7 +778,7 @@ macro_rules! unify {
 macro_rules! unify_fn {
     ($machine_st:expr, $($value:expr),*) => {{
         $($machine_st.pdl.push($value);)*
-        ($machine_st.unify_fn)($machine_st)
+        ($machine_st.unify_fn)(&mut $machine_st)
     }};
 }