- // MIR for `f` before CopyProp
+ // MIR for `f` after CopyProp
  
  fn f(_1: bool) -> bool {
      let mut _0: bool;
      let mut _2: bool;
      let mut _3: bool;
  
      bb0: {
          goto -> bb1;
      }
  
      bb1: {
          _3 = copy _1;
          switchInt(copy _3) -> [0: bb3, otherwise: bb2];
      }
  
      bb2: {
          _2 = copy _3;
          _1 = const false;
          goto -> bb1;
      }
  
      bb3: {
          _0 = copy _2;
          return;
      }
  }