- // MIR for `opt` before InstCombine
+ // MIR for `opt` after InstCombine
  
  fn opt(_1: Option<()>) -> bool {
      debug x => _1;                       // in scope 0 at $DIR/not_equal_false.rs:3:8: 3:9
      let mut _0: bool;                    // return place in scope 0 at $DIR/not_equal_false.rs:3:26: 3:30
      let mut _2: bool;                    // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
      let mut _3: isize;                   // in scope 0 at $DIR/not_equal_false.rs:4:17: 4:21
      let mut _4: bool;                    // in scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
      let mut _5: isize;                   // in scope 0 at $DIR/not_equal_false.rs:4:38: 4:45
      let mut _6: isize;                   // in scope 0 at $DIR/not_equal_false.rs:4:17: 4:21
      let mut _7: isize;                   // in scope 0 at $DIR/not_equal_false.rs:4:38: 4:45
      let mut _8: bool;                    // in scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
  
      bb0: {
          StorageLive(_2);                 // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
          _3 = discriminant(_1);           // scope 0 at $DIR/not_equal_false.rs:4:17: 4:21
          StorageLive(_6);                 // scope 0 at $DIR/not_equal_false.rs:4:17: 4:21
          _6 = move _3;                    // scope 0 at $DIR/not_equal_false.rs:4:17: 4:21
          _2 = Eq(_6, const 0_isize);      // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
          StorageDead(_6);                 // scope 0 at $DIR/not_equal_false.rs:4:17: 4:21
          goto -> bb4;                     // scope 0 at $DIR/not_equal_false.rs:4:17: 4:21
      }
  
      bb1: {
          _0 = const true;                 // scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
          goto -> bb3;                     // scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
      }
  
      bb2: {
          StorageLive(_4);                 // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
          _5 = discriminant(_1);           // scope 0 at $DIR/not_equal_false.rs:4:38: 4:45
          StorageLive(_7);                 // scope 0 at $DIR/not_equal_false.rs:4:38: 4:45
          _7 = move _5;                    // scope 0 at $DIR/not_equal_false.rs:4:38: 4:45
          _4 = Eq(_7, const 1_isize);      // scope 0 at $SRC_DIR/core/src/macros/mod.rs:LL:COL
          StorageDead(_7);                 // scope 0 at $DIR/not_equal_false.rs:4:38: 4:45
          goto -> bb5;                     // scope 0 at $DIR/not_equal_false.rs:4:38: 4:45
      }
  
      bb3: {
          StorageDead(_4);                 // scope 0 at $DIR/not_equal_false.rs:4:45: 4:46
          StorageDead(_2);                 // scope 0 at $DIR/not_equal_false.rs:4:45: 4:46
          return;                          // scope 0 at $DIR/not_equal_false.rs:5:2: 5:2
      }
  
      bb4: {
          switchInt(move _2) -> [false: bb2, otherwise: bb1]; // scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
      }
  
      bb5: {
          StorageLive(_8);                 // scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
          _8 = move _4;                    // scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
-         _0 = Ne(_8, const false);        // scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
+         _0 = _8;                         // scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
          StorageDead(_8);                 // scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
          goto -> bb3;                     // scope 0 at $DIR/not_equal_false.rs:4:5: 4:46
      }
  }