src/test/mir-opt/basic_assignment.rs

   1 // Copyright 2017 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 // this tests move up progration, which is not yet implemented
  12 // Copyright 2017 The Rust Project Developers. See the COPYRIGHT
  13 // file at the top-level directory of this distribution and at
  14 // http://rust-lang.org/COPYRIGHT.
  15 //
  16 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
  17 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
  18 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
  19 // option. This file may not be copied, modified, or distributed
  20 // except according to those terms.
  21
  22 // check that codegen of assignment expressions is sane. Assignments
  23 // tend to be absent in simple code, so subtle breakage in them can
  24 // leave a quite hard-to-find trail of destruction.
  25
  26 fn main() {
  27     let nodrop_x = false;
  28     let nodrop_y;
  29
  30     nodrop_y = nodrop_x;
  31
  32     let drop_x : Option<Box<u32>> = None;
  33     let drop_y;
  34
  35     drop_y = drop_x;
  36 }
  37
  38 // END RUST SOURCE
  39 // START rustc.node4.SimplifyCfg-initial.after.mir
  40 //     bb0: {
  41 //         StorageLive(_1);
  42 //         _1 = const false;
  43 //         StorageLive(_2);
  44 //         StorageLive(_3);
  45 //         _3 = _1;
  46 //         _2 = _3;
  47 //         StorageDead(_3);
  48 //         StorageLive(_4);
  49 //         _4 = std::option::Option<std::boxed::Box<u32>>::None;
  50 //         StorageLive(_6);
  51 //         StorageLive(_7);
  52 //         _7 = _4;
  53 //         replace(_6 <- _7) -> [return: bb5, unwind: bb4];
  54 //     }
  55 //     bb1: {
  56 //         resume;
  57 //     }
  58 //     bb2: {
  59 //         drop(_4) -> bb1;
  60 //     }
  61 //     bb3: {
  62 //         drop(_6) -> bb2;
  63 //     }
  64 //     bb4: {
  65 //         drop(_7) -> bb3;
  66 //     }
  67 //     bb5: {
  68 //         drop(_7) -> [return: bb6, unwind: bb3];
  69 //     }
  70 //     bb6: {
  71 //         StorageDead(_7);
  72 //         _0 = ();
  73 //         drop(_6) -> [return: bb7, unwind: bb2];
  74 //     }
  75 //     bb7: {
  76 //         StorageDead(_6);
  77 //         drop(_4) -> bb8;
  78 //     }
  79 //     bb8: {
  80 //         StorageDead(_4);
  81 //         StorageDead(_2);
  82 //         StorageDead(_1);
  83 //         return;
  84 //     }
  85 // END rustc.node4.SimplifyCfg-initial.after.mir