From 00eec854f167c546cedd0911f4cc302a54ed0be9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Tomasz=20Mi=C4=85sko?= Date: Thu, 23 Feb 2023 00:00:00 +0000 Subject: [PATCH 1/3] Emit diff instead of after mir in ElaborateDrops tests to make it easy to understand chnages made by elaboration. --- .../issue_41110.main.ElaborateDrops.after.mir | 70 -------- .../issue_41110.main.ElaborateDrops.diff | 75 +++++++++ tests/mir-opt/issue_41110.rs | 4 +- .../issue_41110.test.ElaborateDrops.after.mir | 101 ----------- .../issue_41110.test.ElaborateDrops.diff | 110 ++++++++++++ .../issue_41888.main.ElaborateDrops.after.mir | 152 ----------------- .../issue_41888.main.ElaborateDrops.diff | 159 ++++++++++++++++++ tests/mir-opt/issue_41888.rs | 2 +- 8 files changed, 347 insertions(+), 326 deletions(-) delete mode 100644 tests/mir-opt/issue_41110.main.ElaborateDrops.after.mir create mode 100644 tests/mir-opt/issue_41110.main.ElaborateDrops.diff delete mode 100644 tests/mir-opt/issue_41110.test.ElaborateDrops.after.mir create mode 100644 tests/mir-opt/issue_41110.test.ElaborateDrops.diff delete mode 100644 tests/mir-opt/issue_41888.main.ElaborateDrops.after.mir create mode 100644 tests/mir-opt/issue_41888.main.ElaborateDrops.diff diff --git a/tests/mir-opt/issue_41110.main.ElaborateDrops.after.mir b/tests/mir-opt/issue_41110.main.ElaborateDrops.after.mir deleted file mode 100644 index c2ea3ac502f89..0000000000000 --- a/tests/mir-opt/issue_41110.main.ElaborateDrops.after.mir +++ /dev/null @@ -1,70 +0,0 @@ -// MIR for `main` after ElaborateDrops - -fn main() -> () { - let mut _0: (); // return place in scope 0 at $DIR/issue_41110.rs:+0:11: +0:11 - let _1: (); // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 - let mut _2: S; // in scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 - let mut _3: S; // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:27 - let mut _4: S; // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:22 - let mut _5: bool; // in scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 - scope 1 { - debug x => _1; // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10 - } - - bb0: { - _5 = const false; // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 - StorageLive(_1); // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 - StorageLive(_2); // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 - _5 = const true; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 - _2 = S; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 - StorageLive(_3); // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27 - StorageLive(_4); // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22 - _4 = S; // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22 - _3 = S::id(move _4) -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27 - // mir::Constant - // + span: $DIR/issue_41110.rs:8:23: 8:25 - // + literal: Const { ty: fn(S) -> S {S::id}, val: Value() } - } - - bb1: { - StorageDead(_4); // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27 - _5 = const false; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28 - _1 = S::other(move _2, move _3) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28 - // mir::Constant - // + span: $DIR/issue_41110.rs:8:15: 8:20 - // + literal: Const { ty: fn(S, S) {S::other}, val: Value() } - } - - bb2: { - StorageDead(_3); // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 - _5 = const false; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 - StorageDead(_2); // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 - _0 = const (); // scope 0 at $DIR/issue_41110.rs:+0:11: +2:2 - StorageDead(_1); // scope 0 at $DIR/issue_41110.rs:+2:1: +2:2 - return; // scope 0 at $DIR/issue_41110.rs:+2:2: +2:2 - } - - bb3 (cleanup): { - goto -> bb5; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 - } - - bb4 (cleanup): { - goto -> bb5; // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27 - } - - bb5 (cleanup): { - goto -> bb8; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 - } - - bb6 (cleanup): { - resume; // scope 0 at $DIR/issue_41110.rs:+0:1: +2:2 - } - - bb7 (cleanup): { - drop(_2) -> bb6; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 - } - - bb8 (cleanup): { - switchInt(_5) -> [0: bb6, otherwise: bb7]; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 - } -} diff --git a/tests/mir-opt/issue_41110.main.ElaborateDrops.diff b/tests/mir-opt/issue_41110.main.ElaborateDrops.diff new file mode 100644 index 0000000000000..7ac75b51a370f --- /dev/null +++ b/tests/mir-opt/issue_41110.main.ElaborateDrops.diff @@ -0,0 +1,75 @@ +- // MIR for `main` before ElaborateDrops ++ // MIR for `main` after ElaborateDrops + + fn main() -> () { + let mut _0: (); // return place in scope 0 at $DIR/issue_41110.rs:+0:11: +0:11 + let _1: (); // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 + let mut _2: S; // in scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 + let mut _3: S; // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:27 + let mut _4: S; // in scope 0 at $DIR/issue_41110.rs:+1:21: +1:22 ++ let mut _5: bool; // in scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 + scope 1 { + debug x => _1; // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10 + } + + bb0: { ++ _5 = const false; // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 + StorageLive(_1); // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 + StorageLive(_2); // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 ++ _5 = const true; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 + _2 = S; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 + StorageLive(_3); // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27 + StorageLive(_4); // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22 + _4 = S; // scope 0 at $DIR/issue_41110.rs:+1:21: +1:22 + _3 = S::id(move _4) -> [return: bb1, unwind: bb4]; // scope 0 at $DIR/issue_41110.rs:+1:21: +1:27 + // mir::Constant + // + span: $DIR/issue_41110.rs:8:23: 8:25 + // + literal: Const { ty: fn(S) -> S {S::id}, val: Value() } + } + + bb1: { + StorageDead(_4); // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27 ++ _5 = const false; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28 + _1 = S::other(move _2, move _3) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:28 + // mir::Constant + // + span: $DIR/issue_41110.rs:8:15: 8:20 + // + literal: Const { ty: fn(S, S) {S::other}, val: Value() } + } + + bb2: { + StorageDead(_3); // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 ++ _5 = const false; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 + StorageDead(_2); // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 + _0 = const (); // scope 0 at $DIR/issue_41110.rs:+0:11: +2:2 + StorageDead(_1); // scope 0 at $DIR/issue_41110.rs:+2:1: +2:2 + return; // scope 0 at $DIR/issue_41110.rs:+2:2: +2:2 + } + + bb3 (cleanup): { +- drop(_3) -> bb5; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 ++ goto -> bb5; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 + } + + bb4 (cleanup): { +- drop(_4) -> bb5; // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27 ++ goto -> bb5; // scope 0 at $DIR/issue_41110.rs:+1:26: +1:27 + } + + bb5 (cleanup): { +- drop(_2) -> bb6; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 ++ goto -> bb8; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 + } + + bb6 (cleanup): { + resume; // scope 0 at $DIR/issue_41110.rs:+0:1: +2:2 ++ } ++ ++ bb7 (cleanup): { ++ drop(_2) -> bb6; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 ++ } ++ ++ bb8 (cleanup): { ++ switchInt(_5) -> [0: bb6, otherwise: bb7]; // scope 0 at $DIR/issue_41110.rs:+1:27: +1:28 + } + } + diff --git a/tests/mir-opt/issue_41110.rs b/tests/mir-opt/issue_41110.rs index 638dc601ec869..e1067ce53e41d 100644 --- a/tests/mir-opt/issue_41110.rs +++ b/tests/mir-opt/issue_41110.rs @@ -3,14 +3,14 @@ // check that we don't emit multiple drop flags when they are not needed. -// EMIT_MIR issue_41110.main.ElaborateDrops.after.mir +// EMIT_MIR issue_41110.main.ElaborateDrops.diff fn main() { let x = S.other(S.id()); } // no_mangle to make sure this gets instantiated even in an executable. #[no_mangle] -// EMIT_MIR issue_41110.test.ElaborateDrops.after.mir +// EMIT_MIR issue_41110.test.ElaborateDrops.diff pub fn test() { let u = S; let mut v = S; diff --git a/tests/mir-opt/issue_41110.test.ElaborateDrops.after.mir b/tests/mir-opt/issue_41110.test.ElaborateDrops.after.mir deleted file mode 100644 index 82989c3f071b4..0000000000000 --- a/tests/mir-opt/issue_41110.test.ElaborateDrops.after.mir +++ /dev/null @@ -1,101 +0,0 @@ -// MIR for `test` after ElaborateDrops - -fn test() -> () { - let mut _0: (); // return place in scope 0 at $DIR/issue_41110.rs:+0:15: +0:15 - let _1: S; // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 - let _3: (); // in scope 0 at $DIR/issue_41110.rs:+3:5: +3:12 - let mut _4: S; // in scope 0 at $DIR/issue_41110.rs:+3:10: +3:11 - let mut _5: S; // in scope 0 at $DIR/issue_41110.rs:+4:9: +4:10 - let mut _6: bool; // in scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 - scope 1 { - debug u => _1; // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10 - let mut _2: S; // in scope 1 at $DIR/issue_41110.rs:+2:9: +2:14 - scope 2 { - debug v => _2; // in scope 2 at $DIR/issue_41110.rs:+2:9: +2:14 - } - } - - bb0: { - _6 = const false; // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 - StorageLive(_1); // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 - _6 = const true; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 - _1 = S; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 - StorageLive(_2); // scope 1 at $DIR/issue_41110.rs:+2:9: +2:14 - _2 = S; // scope 1 at $DIR/issue_41110.rs:+2:17: +2:18 - StorageLive(_3); // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12 - StorageLive(_4); // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11 - _4 = move _2; // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11 - _3 = std::mem::drop::(move _4) -> [return: bb1, unwind: bb7]; // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12 - // mir::Constant - // + span: $DIR/issue_41110.rs:17:5: 17:9 - // + literal: Const { ty: fn(S) {std::mem::drop::}, val: Value() } - } - - bb1: { - StorageDead(_4); // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12 - StorageDead(_3); // scope 2 at $DIR/issue_41110.rs:+3:12: +3:13 - StorageLive(_5); // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 - _6 = const false; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 - _5 = move _1; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 - goto -> bb12; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 - } - - bb2: { - goto -> bb3; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 - } - - bb3: { - StorageDead(_5); // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 - _0 = const (); // scope 0 at $DIR/issue_41110.rs:+0:15: +5:2 - drop(_2) -> [return: bb4, unwind: bb9]; // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2 - } - - bb4: { - StorageDead(_2); // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2 - goto -> bb5; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 - } - - bb5: { - _6 = const false; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 - StorageDead(_1); // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 - return; // scope 0 at $DIR/issue_41110.rs:+5:2: +5:2 - } - - bb6 (cleanup): { - goto -> bb8; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 - } - - bb7 (cleanup): { - goto -> bb8; // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12 - } - - bb8 (cleanup): { - goto -> bb9; // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2 - } - - bb9 (cleanup): { - goto -> bb14; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 - } - - bb10 (cleanup): { - resume; // scope 0 at $DIR/issue_41110.rs:+0:1: +5:2 - } - - bb11 (cleanup): { - _2 = move _5; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 - goto -> bb6; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 - } - - bb12: { - _2 = move _5; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 - goto -> bb2; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 - } - - bb13 (cleanup): { - drop(_1) -> bb10; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 - } - - bb14 (cleanup): { - switchInt(_6) -> [0: bb10, otherwise: bb13]; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 - } -} diff --git a/tests/mir-opt/issue_41110.test.ElaborateDrops.diff b/tests/mir-opt/issue_41110.test.ElaborateDrops.diff new file mode 100644 index 0000000000000..d979a6a722cd5 --- /dev/null +++ b/tests/mir-opt/issue_41110.test.ElaborateDrops.diff @@ -0,0 +1,110 @@ +- // MIR for `test` before ElaborateDrops ++ // MIR for `test` after ElaborateDrops + + fn test() -> () { + let mut _0: (); // return place in scope 0 at $DIR/issue_41110.rs:+0:15: +0:15 + let _1: S; // in scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 + let _3: (); // in scope 0 at $DIR/issue_41110.rs:+3:5: +3:12 + let mut _4: S; // in scope 0 at $DIR/issue_41110.rs:+3:10: +3:11 + let mut _5: S; // in scope 0 at $DIR/issue_41110.rs:+4:9: +4:10 ++ let mut _6: bool; // in scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 + scope 1 { + debug u => _1; // in scope 1 at $DIR/issue_41110.rs:+1:9: +1:10 + let mut _2: S; // in scope 1 at $DIR/issue_41110.rs:+2:9: +2:14 + scope 2 { + debug v => _2; // in scope 2 at $DIR/issue_41110.rs:+2:9: +2:14 + } + } + + bb0: { ++ _6 = const false; // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 + StorageLive(_1); // scope 0 at $DIR/issue_41110.rs:+1:9: +1:10 ++ _6 = const true; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 + _1 = S; // scope 0 at $DIR/issue_41110.rs:+1:13: +1:14 + StorageLive(_2); // scope 1 at $DIR/issue_41110.rs:+2:9: +2:14 + _2 = S; // scope 1 at $DIR/issue_41110.rs:+2:17: +2:18 + StorageLive(_3); // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12 + StorageLive(_4); // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11 + _4 = move _2; // scope 2 at $DIR/issue_41110.rs:+3:10: +3:11 + _3 = std::mem::drop::(move _4) -> [return: bb1, unwind: bb7]; // scope 2 at $DIR/issue_41110.rs:+3:5: +3:12 + // mir::Constant + // + span: $DIR/issue_41110.rs:17:5: 17:9 + // + literal: Const { ty: fn(S) {std::mem::drop::}, val: Value() } + } + + bb1: { + StorageDead(_4); // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12 + StorageDead(_3); // scope 2 at $DIR/issue_41110.rs:+3:12: +3:13 + StorageLive(_5); // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 ++ _6 = const false; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 + _5 = move _1; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 +- replace(_2 <- move _5) -> [return: bb2, unwind: bb6]; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 ++ goto -> bb12; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 + } + + bb2: { +- drop(_5) -> [return: bb3, unwind: bb8]; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 ++ goto -> bb3; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 + } + + bb3: { + StorageDead(_5); // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 + _0 = const (); // scope 0 at $DIR/issue_41110.rs:+0:15: +5:2 + drop(_2) -> [return: bb4, unwind: bb9]; // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2 + } + + bb4: { + StorageDead(_2); // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2 +- drop(_1) -> bb5; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 ++ goto -> bb5; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 + } + + bb5: { ++ _6 = const false; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 + StorageDead(_1); // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 + return; // scope 0 at $DIR/issue_41110.rs:+5:2: +5:2 + } + + bb6 (cleanup): { +- drop(_5) -> bb8; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 ++ goto -> bb8; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 + } + + bb7 (cleanup): { +- drop(_4) -> bb8; // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12 ++ goto -> bb8; // scope 2 at $DIR/issue_41110.rs:+3:11: +3:12 + } + + bb8 (cleanup): { +- drop(_2) -> bb9; // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2 ++ goto -> bb9; // scope 1 at $DIR/issue_41110.rs:+5:1: +5:2 + } + + bb9 (cleanup): { +- drop(_1) -> bb10; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 ++ goto -> bb14; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 + } + + bb10 (cleanup): { + resume; // scope 0 at $DIR/issue_41110.rs:+0:1: +5:2 ++ } ++ ++ bb11 (cleanup): { ++ _2 = move _5; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 ++ goto -> bb6; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 ++ } ++ ++ bb12: { ++ _2 = move _5; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 ++ goto -> bb2; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 ++ } ++ ++ bb13 (cleanup): { ++ drop(_1) -> bb10; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 ++ } ++ ++ bb14 (cleanup): { ++ switchInt(_6) -> [0: bb10, otherwise: bb13]; // scope 0 at $DIR/issue_41110.rs:+5:1: +5:2 + } + } + diff --git a/tests/mir-opt/issue_41888.main.ElaborateDrops.after.mir b/tests/mir-opt/issue_41888.main.ElaborateDrops.after.mir deleted file mode 100644 index 00504273245b1..0000000000000 --- a/tests/mir-opt/issue_41888.main.ElaborateDrops.after.mir +++ /dev/null @@ -1,152 +0,0 @@ -// MIR for `main` after ElaborateDrops - -fn main() -> () { - let mut _0: (); // return place in scope 0 at $DIR/issue_41888.rs:+0:11: +0:11 - let _1: E; // in scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 - let mut _2: bool; // in scope 0 at $DIR/issue_41888.rs:+2:8: +2:14 - let mut _3: E; // in scope 0 at $DIR/issue_41888.rs:+3:13: +3:20 - let mut _4: K; // in scope 0 at $DIR/issue_41888.rs:+3:18: +3:19 - let mut _5: isize; // in scope 0 at $DIR/issue_41888.rs:+4:16: +4:24 - let mut _7: bool; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - let mut _8: bool; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - let mut _9: bool; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - let mut _10: isize; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - let mut _11: isize; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - scope 1 { - debug e => _1; // in scope 1 at $DIR/issue_41888.rs:+1:9: +1:10 - scope 2 { - debug _k => _6; // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 - let _6: K; // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 - } - } - - bb0: { - _9 = const false; // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 - _7 = const false; // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 - _8 = const false; // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 - StorageLive(_1); // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 - StorageLive(_2); // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14 - _2 = cond() -> [return: bb1, unwind: bb11]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14 - // mir::Constant - // + span: $DIR/issue_41888.rs:8:8: 8:12 - // + literal: Const { ty: fn() -> bool {cond}, val: Value() } - } - - bb1: { - switchInt(move _2) -> [0: bb7, otherwise: bb2]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14 - } - - bb2: { - StorageLive(_3); // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20 - StorageLive(_4); // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19 - _4 = K; // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19 - _3 = E::F(move _4); // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20 - StorageDead(_4); // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 - goto -> bb14; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - } - - bb3: { - goto -> bb4; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 - } - - bb4: { - StorageDead(_3); // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 - _5 = discriminant(_1); // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24 - switchInt(move _5) -> [0: bb5, otherwise: bb6]; // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24 - } - - bb5: { - StorageLive(_6); // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 - _9 = const false; // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 - _6 = move ((_1 as F).0: K); // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 - _0 = const (); // scope 2 at $DIR/issue_41888.rs:+4:29: +7:10 - StorageDead(_6); // scope 1 at $DIR/issue_41888.rs:+7:9: +7:10 - goto -> bb8; // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10 - } - - bb6: { - _0 = const (); // scope 1 at $DIR/issue_41888.rs:+7:10: +7:10 - goto -> bb8; // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10 - } - - bb7: { - _0 = const (); // scope 1 at $DIR/issue_41888.rs:+8:6: +8:6 - goto -> bb8; // scope 1 at $DIR/issue_41888.rs:+2:5: +8:6 - } - - bb8: { - StorageDead(_2); // scope 1 at $DIR/issue_41888.rs:+8:5: +8:6 - goto -> bb20; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } - - bb9: { - _7 = const false; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - _8 = const false; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - _9 = const false; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - StorageDead(_1); // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - return; // scope 0 at $DIR/issue_41888.rs:+9:2: +9:2 - } - - bb10 (cleanup): { - goto -> bb11; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 - } - - bb11 (cleanup): { - goto -> bb12; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } - - bb12 (cleanup): { - resume; // scope 0 at $DIR/issue_41888.rs:+0:1: +9:2 - } - - bb13 (cleanup): { - _7 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - _8 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - _9 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - _1 = move _3; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - goto -> bb10; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - } - - bb14: { - _7 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - _8 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - _9 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - _1 = move _3; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - goto -> bb3; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 - } - - bb15: { - _7 = const false; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - goto -> bb9; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } - - bb16 (cleanup): { - goto -> bb12; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } - - bb17: { - drop(_1) -> [return: bb15, unwind: bb12]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } - - bb18 (cleanup): { - drop(_1) -> bb12; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } - - bb19: { - _10 = discriminant(_1); // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - switchInt(move _10) -> [0: bb15, otherwise: bb17]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } - - bb20: { - switchInt(_7) -> [0: bb15, otherwise: bb19]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } - - bb21 (cleanup): { - _11 = discriminant(_1); // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - switchInt(move _11) -> [0: bb16, otherwise: bb18]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } - - bb22 (cleanup): { - switchInt(_7) -> [0: bb12, otherwise: bb21]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 - } -} diff --git a/tests/mir-opt/issue_41888.main.ElaborateDrops.diff b/tests/mir-opt/issue_41888.main.ElaborateDrops.diff new file mode 100644 index 0000000000000..07740eacadf68 --- /dev/null +++ b/tests/mir-opt/issue_41888.main.ElaborateDrops.diff @@ -0,0 +1,159 @@ +- // MIR for `main` before ElaborateDrops ++ // MIR for `main` after ElaborateDrops + + fn main() -> () { + let mut _0: (); // return place in scope 0 at $DIR/issue_41888.rs:+0:11: +0:11 + let _1: E; // in scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 + let mut _2: bool; // in scope 0 at $DIR/issue_41888.rs:+2:8: +2:14 + let mut _3: E; // in scope 0 at $DIR/issue_41888.rs:+3:13: +3:20 + let mut _4: K; // in scope 0 at $DIR/issue_41888.rs:+3:18: +3:19 + let mut _5: isize; // in scope 0 at $DIR/issue_41888.rs:+4:16: +4:24 ++ let mut _7: bool; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ let mut _8: bool; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ let mut _9: bool; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ let mut _10: isize; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ let mut _11: isize; // in scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 + scope 1 { + debug e => _1; // in scope 1 at $DIR/issue_41888.rs:+1:9: +1:10 + scope 2 { + debug _k => _6; // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 + let _6: K; // in scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 + } + } + + bb0: { ++ _9 = const false; // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 ++ _7 = const false; // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 ++ _8 = const false; // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 + StorageLive(_1); // scope 0 at $DIR/issue_41888.rs:+1:9: +1:10 + StorageLive(_2); // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14 + _2 = cond() -> [return: bb1, unwind: bb11]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14 + // mir::Constant + // + span: $DIR/issue_41888.rs:8:8: 8:12 + // + literal: Const { ty: fn() -> bool {cond}, val: Value() } + } + + bb1: { + switchInt(move _2) -> [0: bb7, otherwise: bb2]; // scope 1 at $DIR/issue_41888.rs:+2:8: +2:14 + } + + bb2: { + StorageLive(_3); // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20 + StorageLive(_4); // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19 + _4 = K; // scope 1 at $DIR/issue_41888.rs:+3:18: +3:19 + _3 = E::F(move _4); // scope 1 at $DIR/issue_41888.rs:+3:13: +3:20 + StorageDead(_4); // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 +- replace(_1 <- move _3) -> [return: bb3, unwind: bb10]; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ goto -> bb14; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 + } + + bb3: { +- drop(_3) -> [return: bb4, unwind: bb11]; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 ++ goto -> bb4; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 + } + + bb4: { + StorageDead(_3); // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 + _5 = discriminant(_1); // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24 + switchInt(move _5) -> [0: bb5, otherwise: bb6]; // scope 2 at $DIR/issue_41888.rs:+4:16: +4:24 + } + + bb5: { + StorageLive(_6); // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 ++ _9 = const false; // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 + _6 = move ((_1 as F).0: K); // scope 2 at $DIR/issue_41888.rs:+4:21: +4:23 + _0 = const (); // scope 2 at $DIR/issue_41888.rs:+4:29: +7:10 + StorageDead(_6); // scope 1 at $DIR/issue_41888.rs:+7:9: +7:10 + goto -> bb8; // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10 + } + + bb6: { + _0 = const (); // scope 1 at $DIR/issue_41888.rs:+7:10: +7:10 + goto -> bb8; // scope 1 at $DIR/issue_41888.rs:+4:9: +7:10 + } + + bb7: { + _0 = const (); // scope 1 at $DIR/issue_41888.rs:+8:6: +8:6 + goto -> bb8; // scope 1 at $DIR/issue_41888.rs:+2:5: +8:6 + } + + bb8: { + StorageDead(_2); // scope 1 at $DIR/issue_41888.rs:+8:5: +8:6 +- drop(_1) -> bb9; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ goto -> bb20; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 + } + + bb9: { ++ _7 = const false; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ _8 = const false; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ _9 = const false; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 + StorageDead(_1); // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 + return; // scope 0 at $DIR/issue_41888.rs:+9:2: +9:2 + } + + bb10 (cleanup): { +- drop(_3) -> bb11; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 ++ goto -> bb11; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 + } + + bb11 (cleanup): { +- drop(_1) -> bb12; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ goto -> bb12; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 + } + + bb12 (cleanup): { + resume; // scope 0 at $DIR/issue_41888.rs:+0:1: +9:2 ++ } ++ ++ bb13 (cleanup): { ++ _7 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ _8 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ _9 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ _1 = move _3; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ goto -> bb10; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ } ++ ++ bb14: { ++ _7 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ _8 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ _9 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ _1 = move _3; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ goto -> bb3; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ } ++ ++ bb15: { ++ _7 = const false; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ goto -> bb9; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ } ++ ++ bb16 (cleanup): { ++ goto -> bb12; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ } ++ ++ bb17: { ++ drop(_1) -> [return: bb15, unwind: bb12]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ } ++ ++ bb18 (cleanup): { ++ drop(_1) -> bb12; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ } ++ ++ bb19: { ++ _10 = discriminant(_1); // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ switchInt(move _10) -> [0: bb15, otherwise: bb17]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ } ++ ++ bb20: { ++ switchInt(_7) -> [0: bb15, otherwise: bb19]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ } ++ ++ bb21 (cleanup): { ++ _11 = discriminant(_1); // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ switchInt(move _11) -> [0: bb16, otherwise: bb18]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 ++ } ++ ++ bb22 (cleanup): { ++ switchInt(_7) -> [0: bb12, otherwise: bb21]; // scope 0 at $DIR/issue_41888.rs:+9:1: +9:2 + } + } + diff --git a/tests/mir-opt/issue_41888.rs b/tests/mir-opt/issue_41888.rs index c1046c14dbf85..0f10c0a1d09f1 100644 --- a/tests/mir-opt/issue_41888.rs +++ b/tests/mir-opt/issue_41888.rs @@ -2,7 +2,7 @@ // check that we clear the "ADT master drop flag" even when there are // no fields to be dropped. -// EMIT_MIR issue_41888.main.ElaborateDrops.after.mir +// EMIT_MIR issue_41888.main.ElaborateDrops.diff fn main() { let e; if cond() { From 23e3840014e17cd20f6ebe5e268133b3ce5ab1a6 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Tomasz=20Mi=C4=85sko?= Date: Thu, 5 Jan 2023 10:15:33 +0100 Subject: [PATCH 2/3] Remove dead unwinds before drop elaboration As a part of drop elaboration, we identify dead unwinds, i.e., unwind edges on a drop terminators which are known to be unreachable, because there is no need to drop anything. Previously, the data flow framework was informed about the dead unwinds, and it assumed those edges are absent from MIR. Unfortunately, the data flow framework wasn't consistent in maintaining this assumption. In particular, if a block was reachable only through a dead unwind edge, its state was propagated to other blocks still. This became an issue in the context of change removes DropAndReplace terminator, since it introduces initialization into cleanup blocks. To avoid this issue, remove unreachable unwind edges before the drop elaboration, and elaborate only blocks that remain reachable. --- .../src/framework/direction.rs | 31 +--------- .../src/framework/engine.rs | 32 +---------- .../src/elaborate_drops.rs | 57 +++++++++++++------ 3 files changed, 44 insertions(+), 76 deletions(-) diff --git a/compiler/rustc_mir_dataflow/src/framework/direction.rs b/compiler/rustc_mir_dataflow/src/framework/direction.rs index 077a21fc8afc0..2ae3ae02fcc4e 100644 --- a/compiler/rustc_mir_dataflow/src/framework/direction.rs +++ b/compiler/rustc_mir_dataflow/src/framework/direction.rs @@ -1,4 +1,3 @@ -use rustc_index::bit_set::BitSet; use rustc_middle::mir::{self, BasicBlock, Location, SwitchTargets}; use rustc_middle::ty::TyCtxt; use std::ops::RangeInclusive; @@ -54,7 +53,6 @@ pub trait Direction { analysis: &A, tcx: TyCtxt<'tcx>, body: &mir::Body<'tcx>, - dead_unwinds: Option<&BitSet>, exit_state: &mut A::Domain, block: (BasicBlock, &'_ mir::BasicBlockData<'tcx>), propagate: impl FnMut(BasicBlock, &A::Domain), @@ -221,7 +219,6 @@ impl Direction for Backward { analysis: &A, _tcx: TyCtxt<'tcx>, body: &mir::Body<'tcx>, - dead_unwinds: Option<&BitSet>, exit_state: &mut A::Domain, (bb, _bb_data): (BasicBlock, &'_ mir::BasicBlockData<'tcx>), mut propagate: impl FnMut(BasicBlock, &A::Domain), @@ -278,20 +275,6 @@ impl Direction for Backward { } } - // Ignore dead unwinds. - mir::TerminatorKind::Call { cleanup: Some(unwind), .. } - | mir::TerminatorKind::Assert { cleanup: Some(unwind), .. } - | mir::TerminatorKind::Drop { unwind: Some(unwind), .. } - | mir::TerminatorKind::DropAndReplace { unwind: Some(unwind), .. } - | mir::TerminatorKind::FalseUnwind { unwind: Some(unwind), .. } - | mir::TerminatorKind::InlineAsm { cleanup: Some(unwind), .. } - if unwind == bb => - { - if dead_unwinds.map_or(true, |dead| !dead.contains(pred)) { - propagate(pred, exit_state); - } - } - _ => propagate(pred, exit_state), } } @@ -304,7 +287,6 @@ struct BackwardSwitchIntEdgeEffectsApplier<'a, 'tcx, D, F> { exit_state: &'a mut D, bb: BasicBlock, propagate: &'a mut F, - effects_applied: bool, } @@ -484,7 +466,6 @@ impl Direction for Forward { analysis: &A, _tcx: TyCtxt<'tcx>, _body: &mir::Body<'tcx>, - dead_unwinds: Option<&BitSet>, exit_state: &mut A::Domain, (bb, bb_data): (BasicBlock, &'_ mir::BasicBlockData<'tcx>), mut propagate: impl FnMut(BasicBlock, &A::Domain), @@ -502,9 +483,7 @@ impl Direction for Forward { | DropAndReplace { target, unwind, value: _, place: _ } | FalseUnwind { real_target: target, unwind } => { if let Some(unwind) = unwind { - if dead_unwinds.map_or(true, |dead| !dead.contains(bb)) { - propagate(unwind, exit_state); - } + propagate(unwind, exit_state); } propagate(target, exit_state); @@ -534,9 +513,7 @@ impl Direction for Forward { fn_span: _, } => { if let Some(unwind) = cleanup { - if dead_unwinds.map_or(true, |dead| !dead.contains(bb)) { - propagate(unwind, exit_state); - } + propagate(unwind, exit_state); } if let Some(target) = target { @@ -560,9 +537,7 @@ impl Direction for Forward { cleanup, } => { if let Some(unwind) = cleanup { - if dead_unwinds.map_or(true, |dead| !dead.contains(bb)) { - propagate(unwind, exit_state); - } + propagate(unwind, exit_state); } if let Some(target) = destination { diff --git a/compiler/rustc_mir_dataflow/src/framework/engine.rs b/compiler/rustc_mir_dataflow/src/framework/engine.rs index 6ddbe69e17e75..91c3bf0ad21f1 100644 --- a/compiler/rustc_mir_dataflow/src/framework/engine.rs +++ b/compiler/rustc_mir_dataflow/src/framework/engine.rs @@ -12,7 +12,6 @@ use rustc_ast as ast; use rustc_data_structures::work_queue::WorkQueue; use rustc_graphviz as dot; use rustc_hir::def_id::DefId; -use rustc_index::bit_set::BitSet; use rustc_index::vec::{Idx, IndexVec}; use rustc_middle::mir::{self, traversal, BasicBlock}; use rustc_middle::mir::{create_dump_file, dump_enabled}; @@ -78,7 +77,6 @@ where { tcx: TyCtxt<'tcx>, body: &'a mir::Body<'tcx>, - dead_unwinds: Option<&'a BitSet>, entry_sets: IndexVec, pass_name: Option<&'static str>, analysis: A, @@ -154,25 +152,7 @@ where bug!("`initialize_start_block` is not yet supported for backward dataflow analyses"); } - Engine { - analysis, - tcx, - body, - dead_unwinds: None, - pass_name: None, - entry_sets, - apply_trans_for_block, - } - } - - /// Signals that we do not want dataflow state to propagate across unwind edges for these - /// `BasicBlock`s. - /// - /// You must take care that `dead_unwinds` does not contain a `BasicBlock` that *can* actually - /// unwind during execution. Otherwise, your dataflow results will not be correct. - pub fn dead_unwinds(mut self, dead_unwinds: &'a BitSet) -> Self { - self.dead_unwinds = Some(dead_unwinds); - self + Engine { analysis, tcx, body, pass_name: None, entry_sets, apply_trans_for_block } } /// Adds an identifier to the graphviz output for this particular run of a dataflow analysis. @@ -190,14 +170,7 @@ where A::Domain: DebugWithContext, { let Engine { - analysis, - body, - dead_unwinds, - mut entry_sets, - tcx, - apply_trans_for_block, - pass_name, - .. + analysis, body, mut entry_sets, tcx, apply_trans_for_block, pass_name, .. } = self; let mut dirty_queue: WorkQueue = WorkQueue::with_none(body.basic_blocks.len()); @@ -236,7 +209,6 @@ where &analysis, tcx, body, - dead_unwinds, &mut state, (bb, bb_data), |target: BasicBlock, state: &A::Domain| { diff --git a/compiler/rustc_mir_transform/src/elaborate_drops.rs b/compiler/rustc_mir_transform/src/elaborate_drops.rs index c2ff8645635e0..bdfd8dc6e99b5 100644 --- a/compiler/rustc_mir_transform/src/elaborate_drops.rs +++ b/compiler/rustc_mir_transform/src/elaborate_drops.rs @@ -67,13 +67,11 @@ impl<'tcx> MirPass<'tcx> for ElaborateDrops { }; let un_derefer = UnDerefer { tcx: tcx, derefer_sidetable: side_table }; let elaborate_patch = { - let body = &*body; let env = MoveDataParamEnv { move_data, param_env }; - let dead_unwinds = find_dead_unwinds(tcx, body, &env, &un_derefer); + remove_dead_unwinds(tcx, body, &env, &un_derefer); let inits = MaybeInitializedPlaces::new(tcx, body, &env) .into_engine(tcx, body) - .dead_unwinds(&dead_unwinds) .pass_name("elaborate_drops") .iterate_to_fixpoint() .into_results_cursor(body); @@ -81,11 +79,12 @@ impl<'tcx> MirPass<'tcx> for ElaborateDrops { let uninits = MaybeUninitializedPlaces::new(tcx, body, &env) .mark_inactive_variants_as_uninit() .into_engine(tcx, body) - .dead_unwinds(&dead_unwinds) .pass_name("elaborate_drops") .iterate_to_fixpoint() .into_results_cursor(body); + let reachable = traversal::reachable_as_bitset(body); + ElaborateDropsCtxt { tcx, body, @@ -94,6 +93,7 @@ impl<'tcx> MirPass<'tcx> for ElaborateDrops { drop_flags: Default::default(), patch: MirPatch::new(body), un_derefer: un_derefer, + reachable, } .elaborate() }; @@ -102,22 +102,21 @@ impl<'tcx> MirPass<'tcx> for ElaborateDrops { } } -/// Returns the set of basic blocks whose unwind edges are known -/// to not be reachable, because they are `drop` terminators +/// Removes unwind edges which are known to be unreachable, because they are in `drop` terminators /// that can't drop anything. -fn find_dead_unwinds<'tcx>( +fn remove_dead_unwinds<'tcx>( tcx: TyCtxt<'tcx>, - body: &Body<'tcx>, + body: &mut Body<'tcx>, env: &MoveDataParamEnv<'tcx>, und: &UnDerefer<'tcx>, -) -> BitSet { - debug!("find_dead_unwinds({:?})", body.span); +) { + debug!("remove_dead_unwinds({:?})", body.span); // We only need to do this pass once, because unwind edges can only // reach cleanup blocks, which can't have unwind edges themselves. - let mut dead_unwinds = BitSet::new_empty(body.basic_blocks.len()); + let mut dead_unwinds = Vec::new(); let mut flow_inits = MaybeInitializedPlaces::new(tcx, body, &env) .into_engine(tcx, body) - .pass_name("find_dead_unwinds") + .pass_name("remove_dead_unwinds") .iterate_to_fixpoint() .into_results_cursor(body); for (bb, bb_data) in body.basic_blocks.iter_enumerated() { @@ -129,16 +128,16 @@ fn find_dead_unwinds<'tcx>( _ => continue, }; - debug!("find_dead_unwinds @ {:?}: {:?}", bb, bb_data); + debug!("remove_dead_unwinds @ {:?}: {:?}", bb, bb_data); let LookupResult::Exact(path) = env.move_data.rev_lookup.find(place.as_ref()) else { - debug!("find_dead_unwinds: has parent; skipping"); + debug!("remove_dead_unwinds: has parent; skipping"); continue; }; flow_inits.seek_before_primary_effect(body.terminator_loc(bb)); debug!( - "find_dead_unwinds @ {:?}: path({:?})={:?}; init_data={:?}", + "remove_dead_unwinds @ {:?}: path({:?})={:?}; init_data={:?}", bb, place, path, @@ -150,13 +149,22 @@ fn find_dead_unwinds<'tcx>( maybe_live |= flow_inits.contains(child); }); - debug!("find_dead_unwinds @ {:?}: maybe_live={}", bb, maybe_live); + debug!("remove_dead_unwinds @ {:?}: maybe_live={}", bb, maybe_live); if !maybe_live { - dead_unwinds.insert(bb); + dead_unwinds.push(bb); } } - dead_unwinds + if dead_unwinds.is_empty() { + return; + } + + let basic_blocks = body.basic_blocks.as_mut(); + for &bb in dead_unwinds.iter() { + if let Some(unwind) = basic_blocks[bb].terminator_mut().unwind_mut() { + *unwind = None; + } + } } struct InitializationData<'mir, 'tcx> { @@ -290,6 +298,7 @@ struct ElaborateDropsCtxt<'a, 'tcx> { drop_flags: FxHashMap, patch: MirPatch<'tcx>, un_derefer: UnDerefer<'tcx>, + reachable: BitSet, } impl<'b, 'tcx> ElaborateDropsCtxt<'b, 'tcx> { @@ -329,6 +338,9 @@ impl<'b, 'tcx> ElaborateDropsCtxt<'b, 'tcx> { fn collect_drop_flags(&mut self) { for (bb, data) in self.body.basic_blocks.iter_enumerated() { + if !self.reachable.contains(bb) { + continue; + } let terminator = data.terminator(); let place = match terminator.kind { TerminatorKind::Drop { ref place, .. } @@ -384,6 +396,9 @@ impl<'b, 'tcx> ElaborateDropsCtxt<'b, 'tcx> { fn elaborate_drops(&mut self) { for (bb, data) in self.body.basic_blocks.iter_enumerated() { + if !self.reachable.contains(bb) { + continue; + } let loc = Location { block: bb, statement_index: data.statements.len() }; let terminator = data.terminator(); @@ -541,6 +556,9 @@ impl<'b, 'tcx> ElaborateDropsCtxt<'b, 'tcx> { fn drop_flags_for_fn_rets(&mut self) { for (bb, data) in self.body.basic_blocks.iter_enumerated() { + if !self.reachable.contains(bb) { + continue; + } if let TerminatorKind::Call { destination, target: Some(tgt), cleanup: Some(_), .. } = data.terminator().kind @@ -576,6 +594,9 @@ impl<'b, 'tcx> ElaborateDropsCtxt<'b, 'tcx> { // clobbered before they are read. for (bb, data) in self.body.basic_blocks.iter_enumerated() { + if !self.reachable.contains(bb) { + continue; + } debug!("drop_flags_for_locs({:?})", data); for i in 0..(data.statements.len() + 1) { debug!("drop_flag_for_locs: stmt {}", i); From 2a70524397728e4d13e494667fc4865af42c879b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Tomasz=20Mi=C4=85sko?= Date: Thu, 23 Feb 2023 00:00:00 +0000 Subject: [PATCH 3/3] ./x.py test --bless --- tests/mir-opt/issue_41110.test.ElaborateDrops.diff | 5 ++--- tests/mir-opt/issue_41888.main.ElaborateDrops.diff | 5 ++--- 2 files changed, 4 insertions(+), 6 deletions(-) diff --git a/tests/mir-opt/issue_41110.test.ElaborateDrops.diff b/tests/mir-opt/issue_41110.test.ElaborateDrops.diff index d979a6a722cd5..79e3d073be5d7 100644 --- a/tests/mir-opt/issue_41110.test.ElaborateDrops.diff +++ b/tests/mir-opt/issue_41110.test.ElaborateDrops.diff @@ -66,8 +66,7 @@ } bb6 (cleanup): { -- drop(_5) -> bb8; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 -+ goto -> bb8; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 + drop(_5) -> bb8; // scope 2 at $DIR/issue_41110.rs:+4:9: +4:10 } bb7 (cleanup): { @@ -91,7 +90,7 @@ + + bb11 (cleanup): { + _2 = move _5; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 -+ goto -> bb6; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 ++ goto -> bb10; // scope 2 at $DIR/issue_41110.rs:+4:5: +4:6 + } + + bb12: { diff --git a/tests/mir-opt/issue_41888.main.ElaborateDrops.diff b/tests/mir-opt/issue_41888.main.ElaborateDrops.diff index 07740eacadf68..257f0b1e6e8f7 100644 --- a/tests/mir-opt/issue_41888.main.ElaborateDrops.diff +++ b/tests/mir-opt/issue_41888.main.ElaborateDrops.diff @@ -92,8 +92,7 @@ } bb10 (cleanup): { -- drop(_3) -> bb11; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 -+ goto -> bb11; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 + drop(_3) -> bb11; // scope 1 at $DIR/issue_41888.rs:+3:19: +3:20 } bb11 (cleanup): { @@ -110,7 +109,7 @@ + _8 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 + _9 = const true; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 + _1 = move _3; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 -+ goto -> bb10; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 ++ goto -> bb12; // scope 1 at $DIR/issue_41888.rs:+3:9: +3:10 + } + + bb14: {