============ after processor `mut_ref_instrumentation` ================

[variant baseline]
pub fun Trafo::opaque_caller($t0|x: u64): u64 {
     var $t1: u64
     var $t2: u64
     var $t3: u64
  0: trace_local[x]($t0)
  1: $t1 := copy($t0)
  2: $t2 := Trafo::opaque_decr($t1)
  3: $t3 := Trafo::opaque_decr($t2)
  4: trace_return[0]($t3)
  5: return $t3
}


[variant baseline]
pub fun Trafo::opaque_decr($t0|x: u64): u64 {
     var $t1: u64
     var $t2: u64
     var $t3: u64
  0: trace_local[x]($t0)
  1: $t1 := copy($t0)
  2: $t2 := 1
  3: $t3 := -($t1, $t2)
  4: trace_return[0]($t3)
  5: return $t3
}