Skip to content
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 7 additions & 0 deletions compiler/rustc_mir/src/transform/match_branches.rs
Original file line number Diff line number Diff line change
Expand Up @@ -38,6 +38,13 @@ pub struct MatchBranchSimplification;

impl<'tcx> MirPass<'tcx> for MatchBranchSimplification {
fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
// FIXME: This optimization can result in unsoundness, because it introduces
// additional uses of a place holding the discriminant value without ensuring that
// it is valid to do so.
if !tcx.sess.opts.debugging_opts.unsound_mir_opts {
return;
}

let param_env = tcx.param_env(body.source.def_id());
let bbs = body.basic_blocks_mut();
'outer: for bb_idx in bbs.indices() {
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -2,83 +2,83 @@
+ // MIR for `bar` after MatchBranchSimplification

fn bar(_1: i32) -> (bool, bool, bool, bool) {
debug i => _1; // in scope 0 at $DIR/matches_reduce_branches.rs:11:8: 11:9
let mut _0: (bool, bool, bool, bool); // return place in scope 0 at $DIR/matches_reduce_branches.rs:11:19: 11:43
let _2: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:12:9: 12:10
let _6: (); // in scope 0 at $DIR/matches_reduce_branches.rs:17:5: 32:6
let mut _7: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:34:6: 34:7
let mut _8: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:34:9: 34:10
let mut _9: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:34:12: 34:13
let mut _10: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:34:15: 34:16
debug i => _1; // in scope 0 at $DIR/matches_reduce_branches.rs:12:8: 12:9
let mut _0: (bool, bool, bool, bool); // return place in scope 0 at $DIR/matches_reduce_branches.rs:12:19: 12:43
let _2: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:13:9: 13:10
let _6: (); // in scope 0 at $DIR/matches_reduce_branches.rs:18:5: 33:6
let mut _7: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:35:6: 35:7
let mut _8: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:35:9: 35:10
let mut _9: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:35:12: 35:13
let mut _10: bool; // in scope 0 at $DIR/matches_reduce_branches.rs:35:15: 35:16
scope 1 {
debug a => _2; // in scope 1 at $DIR/matches_reduce_branches.rs:12:9: 12:10
let _3: bool; // in scope 1 at $DIR/matches_reduce_branches.rs:13:9: 13:10
debug a => _2; // in scope 1 at $DIR/matches_reduce_branches.rs:13:9: 13:10
let _3: bool; // in scope 1 at $DIR/matches_reduce_branches.rs:14:9: 14:10
scope 2 {
debug b => _3; // in scope 2 at $DIR/matches_reduce_branches.rs:13:9: 13:10
let _4: bool; // in scope 2 at $DIR/matches_reduce_branches.rs:14:9: 14:10
debug b => _3; // in scope 2 at $DIR/matches_reduce_branches.rs:14:9: 14:10
let _4: bool; // in scope 2 at $DIR/matches_reduce_branches.rs:15:9: 15:10
scope 3 {
debug c => _4; // in scope 3 at $DIR/matches_reduce_branches.rs:14:9: 14:10
let _5: bool; // in scope 3 at $DIR/matches_reduce_branches.rs:15:9: 15:10
debug c => _4; // in scope 3 at $DIR/matches_reduce_branches.rs:15:9: 15:10
let _5: bool; // in scope 3 at $DIR/matches_reduce_branches.rs:16:9: 16:10
scope 4 {
debug d => _5; // in scope 4 at $DIR/matches_reduce_branches.rs:15:9: 15:10
debug d => _5; // in scope 4 at $DIR/matches_reduce_branches.rs:16:9: 16:10
}
}
}
}

bb0: {
StorageLive(_2); // scope 0 at $DIR/matches_reduce_branches.rs:12:9: 12:10
StorageLive(_3); // scope 1 at $DIR/matches_reduce_branches.rs:13:9: 13:10
StorageLive(_4); // scope 2 at $DIR/matches_reduce_branches.rs:14:9: 14:10
StorageLive(_5); // scope 3 at $DIR/matches_reduce_branches.rs:15:9: 15:10
StorageLive(_6); // scope 4 at $DIR/matches_reduce_branches.rs:17:5: 32:6
- switchInt(_1) -> [7_i32: bb2, otherwise: bb1]; // scope 4 at $DIR/matches_reduce_branches.rs:18:9: 18:10
+ _2 = Ne(_1, const 7_i32); // scope 4 at $DIR/matches_reduce_branches.rs:19:13: 19:22
+ _3 = Eq(_1, const 7_i32); // scope 4 at $DIR/matches_reduce_branches.rs:20:13: 20:21
+ _4 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:21:13: 21:22
+ _5 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:22:13: 22:21
+ goto -> bb3; // scope 4 at $DIR/matches_reduce_branches.rs:18:9: 18:10
StorageLive(_2); // scope 0 at $DIR/matches_reduce_branches.rs:13:9: 13:10
StorageLive(_3); // scope 1 at $DIR/matches_reduce_branches.rs:14:9: 14:10
StorageLive(_4); // scope 2 at $DIR/matches_reduce_branches.rs:15:9: 15:10
StorageLive(_5); // scope 3 at $DIR/matches_reduce_branches.rs:16:9: 16:10
StorageLive(_6); // scope 4 at $DIR/matches_reduce_branches.rs:18:5: 33:6
- switchInt(_1) -> [7_i32: bb2, otherwise: bb1]; // scope 4 at $DIR/matches_reduce_branches.rs:19:9: 19:10
+ _2 = Ne(_1, const 7_i32); // scope 4 at $DIR/matches_reduce_branches.rs:20:13: 20:22
+ _3 = Eq(_1, const 7_i32); // scope 4 at $DIR/matches_reduce_branches.rs:21:13: 21:21
+ _4 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:22:13: 22:22
+ _5 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:23:13: 23:21
+ goto -> bb3; // scope 4 at $DIR/matches_reduce_branches.rs:19:9: 19:10
}

bb1: {
_2 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:26:13: 26:21
_3 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:27:13: 27:22
_4 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:28:13: 28:22
_5 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:29:13: 29:21
goto -> bb3; // scope 4 at $DIR/matches_reduce_branches.rs:17:5: 32:6
_2 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:27:13: 27:21
_3 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:28:13: 28:22
_4 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:29:13: 29:22
_5 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:30:13: 30:21
goto -> bb3; // scope 4 at $DIR/matches_reduce_branches.rs:18:5: 33:6
}

bb2: {
_2 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:19:13: 19:22
_3 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:20:13: 20:21
_4 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:21:13: 21:22
_5 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:22:13: 22:21
goto -> bb3; // scope 4 at $DIR/matches_reduce_branches.rs:17:5: 32:6
_2 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:20:13: 20:22
_3 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:21:13: 21:21
_4 = const false; // scope 4 at $DIR/matches_reduce_branches.rs:22:13: 22:22
_5 = const true; // scope 4 at $DIR/matches_reduce_branches.rs:23:13: 23:21
goto -> bb3; // scope 4 at $DIR/matches_reduce_branches.rs:18:5: 33:6
}

bb3: {
StorageDead(_6); // scope 4 at $DIR/matches_reduce_branches.rs:32:6: 32:7
StorageLive(_7); // scope 4 at $DIR/matches_reduce_branches.rs:34:6: 34:7
_7 = _2; // scope 4 at $DIR/matches_reduce_branches.rs:34:6: 34:7
StorageLive(_8); // scope 4 at $DIR/matches_reduce_branches.rs:34:9: 34:10
_8 = _3; // scope 4 at $DIR/matches_reduce_branches.rs:34:9: 34:10
StorageLive(_9); // scope 4 at $DIR/matches_reduce_branches.rs:34:12: 34:13
_9 = _4; // scope 4 at $DIR/matches_reduce_branches.rs:34:12: 34:13
StorageLive(_10); // scope 4 at $DIR/matches_reduce_branches.rs:34:15: 34:16
_10 = _5; // scope 4 at $DIR/matches_reduce_branches.rs:34:15: 34:16
(_0.0: bool) = move _7; // scope 4 at $DIR/matches_reduce_branches.rs:34:5: 34:17
(_0.1: bool) = move _8; // scope 4 at $DIR/matches_reduce_branches.rs:34:5: 34:17
(_0.2: bool) = move _9; // scope 4 at $DIR/matches_reduce_branches.rs:34:5: 34:17
(_0.3: bool) = move _10; // scope 4 at $DIR/matches_reduce_branches.rs:34:5: 34:17
StorageDead(_10); // scope 4 at $DIR/matches_reduce_branches.rs:34:16: 34:17
StorageDead(_9); // scope 4 at $DIR/matches_reduce_branches.rs:34:16: 34:17
StorageDead(_8); // scope 4 at $DIR/matches_reduce_branches.rs:34:16: 34:17
StorageDead(_7); // scope 4 at $DIR/matches_reduce_branches.rs:34:16: 34:17
StorageDead(_5); // scope 3 at $DIR/matches_reduce_branches.rs:35:1: 35:2
StorageDead(_4); // scope 2 at $DIR/matches_reduce_branches.rs:35:1: 35:2
StorageDead(_3); // scope 1 at $DIR/matches_reduce_branches.rs:35:1: 35:2
StorageDead(_2); // scope 0 at $DIR/matches_reduce_branches.rs:35:1: 35:2
return; // scope 0 at $DIR/matches_reduce_branches.rs:35:2: 35:2
StorageDead(_6); // scope 4 at $DIR/matches_reduce_branches.rs:33:6: 33:7
StorageLive(_7); // scope 4 at $DIR/matches_reduce_branches.rs:35:6: 35:7
_7 = _2; // scope 4 at $DIR/matches_reduce_branches.rs:35:6: 35:7
StorageLive(_8); // scope 4 at $DIR/matches_reduce_branches.rs:35:9: 35:10
_8 = _3; // scope 4 at $DIR/matches_reduce_branches.rs:35:9: 35:10
StorageLive(_9); // scope 4 at $DIR/matches_reduce_branches.rs:35:12: 35:13
_9 = _4; // scope 4 at $DIR/matches_reduce_branches.rs:35:12: 35:13
StorageLive(_10); // scope 4 at $DIR/matches_reduce_branches.rs:35:15: 35:16
_10 = _5; // scope 4 at $DIR/matches_reduce_branches.rs:35:15: 35:16
(_0.0: bool) = move _7; // scope 4 at $DIR/matches_reduce_branches.rs:35:5: 35:17
(_0.1: bool) = move _8; // scope 4 at $DIR/matches_reduce_branches.rs:35:5: 35:17
(_0.2: bool) = move _9; // scope 4 at $DIR/matches_reduce_branches.rs:35:5: 35:17
(_0.3: bool) = move _10; // scope 4 at $DIR/matches_reduce_branches.rs:35:5: 35:17
StorageDead(_10); // scope 4 at $DIR/matches_reduce_branches.rs:35:16: 35:17
StorageDead(_9); // scope 4 at $DIR/matches_reduce_branches.rs:35:16: 35:17
StorageDead(_8); // scope 4 at $DIR/matches_reduce_branches.rs:35:16: 35:17
StorageDead(_7); // scope 4 at $DIR/matches_reduce_branches.rs:35:16: 35:17
StorageDead(_5); // scope 3 at $DIR/matches_reduce_branches.rs:36:1: 36:2
StorageDead(_4); // scope 2 at $DIR/matches_reduce_branches.rs:36:1: 36:2
StorageDead(_3); // scope 1 at $DIR/matches_reduce_branches.rs:36:1: 36:2
StorageDead(_2); // scope 0 at $DIR/matches_reduce_branches.rs:36:1: 36:2
return; // scope 0 at $DIR/matches_reduce_branches.rs:36:2: 36:2
}
}

Loading