Auto merge of #73262 - wesleywiser:simplifyarmidentity_beta_regression, r=oli-obk

Disable the `SimplifyArmIdentity` pass

This pass is buggy so I'm disabling it to fix a stable-to-beta
regression.

Related to #73223

8 files changed, 87 insertions, 62 deletions

diff --git a/src/librustc_mir/transform/simplify_try.rs b/src/librustc_mir/transform/simplify_try.rs
index 61f9c281559..50136ac3bec 100644
--- a/src/librustc_mir/transform/simplify_try.rs
+++ b/src/librustc_mir/transform/simplify_try.rs
@@ -306,7 +306,11 @@ fn optimization_applies<'tcx>(
 }
 
 impl<'tcx> MirPass<'tcx> for SimplifyArmIdentity {
-    fn run_pass(&self, _: TyCtxt<'tcx>, source: MirSource<'tcx>, body: &mut Body<'tcx>) {
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, source: MirSource<'tcx>, body: &mut Body<'tcx>) {
+        if tcx.sess.opts.debugging_opts.mir_opt_level < 2 {
+            return;
+        }
+
         trace!("running SimplifyArmIdentity on {:?}", source);
         let (basic_blocks, local_decls) = body.basic_blocks_and_local_decls_mut();
         for bb in basic_blocks {
diff --git a/src/test/mir-opt/simplify-arm/rustc.id.SimplifyArmIdentity.diff b/src/test/mir-opt/simplify-arm/rustc.id.SimplifyArmIdentity.diff
index 8d08267d75b..8bb28206964 100644
--- a/src/test/mir-opt/simplify-arm/rustc.id.SimplifyArmIdentity.diff
+++ b/src/test/mir-opt/simplify-arm/rustc.id.SimplifyArmIdentity.diff
@@ -26,15 +26,14 @@
       }
   
       bb3: {
--         StorageLive(_3);                 // scope 0 at $DIR/simplify-arm.rs:11:14: 11:15
--         _3 = ((_1 as Some).0: u8);       // scope 0 at $DIR/simplify-arm.rs:11:14: 11:15
--         StorageLive(_4);                 // scope 1 at $DIR/simplify-arm.rs:11:25: 11:26
--         _4 = _3;                         // scope 1 at $DIR/simplify-arm.rs:11:25: 11:26
--         ((_0 as Some).0: u8) = move _4;  // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
--         discriminant(_0) = 1;            // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
--         StorageDead(_4);                 // scope 1 at $DIR/simplify-arm.rs:11:26: 11:27
--         StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:11:27: 11:28
-+         _0 = move _1;                    // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
+          StorageLive(_3);                 // scope 0 at $DIR/simplify-arm.rs:11:14: 11:15
+          _3 = ((_1 as Some).0: u8);       // scope 0 at $DIR/simplify-arm.rs:11:14: 11:15
+          StorageLive(_4);                 // scope 1 at $DIR/simplify-arm.rs:11:25: 11:26
+          _4 = _3;                         // scope 1 at $DIR/simplify-arm.rs:11:25: 11:26
+          ((_0 as Some).0: u8) = move _4;  // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
+          discriminant(_0) = 1;            // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
+          StorageDead(_4);                 // scope 1 at $DIR/simplify-arm.rs:11:26: 11:27
+          StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:11:27: 11:28
           goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
       }
   
diff --git a/src/test/mir-opt/simplify-arm/rustc.id.SimplifyBranchSame.diff b/src/test/mir-opt/simplify-arm/rustc.id.SimplifyBranchSame.diff
index 23fa9817f80..1226b4feaf4 100644
--- a/src/test/mir-opt/simplify-arm/rustc.id.SimplifyBranchSame.diff
+++ b/src/test/mir-opt/simplify-arm/rustc.id.SimplifyBranchSame.diff
@@ -26,7 +26,14 @@
       }
   
       bb3: {
-          _0 = move _1;                    // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
+          StorageLive(_3);                 // scope 0 at $DIR/simplify-arm.rs:11:14: 11:15
+          _3 = ((_1 as Some).0: u8);       // scope 0 at $DIR/simplify-arm.rs:11:14: 11:15
+          StorageLive(_4);                 // scope 1 at $DIR/simplify-arm.rs:11:25: 11:26
+          _4 = _3;                         // scope 1 at $DIR/simplify-arm.rs:11:25: 11:26
+          ((_0 as Some).0: u8) = move _4;  // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
+          discriminant(_0) = 1;            // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
+          StorageDead(_4);                 // scope 1 at $DIR/simplify-arm.rs:11:26: 11:27
+          StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:11:27: 11:28
           goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
       }
   
diff --git a/src/test/mir-opt/simplify-arm/rustc.id_result.SimplifyArmIdentity.diff b/src/test/mir-opt/simplify-arm/rustc.id_result.SimplifyArmIdentity.diff
index e2a12ca5be2..5a5d67b36d9 100644
--- a/src/test/mir-opt/simplify-arm/rustc.id_result.SimplifyArmIdentity.diff
+++ b/src/test/mir-opt/simplify-arm/rustc.id_result.SimplifyArmIdentity.diff
@@ -22,15 +22,14 @@
       }
   
       bb1: {
--         StorageLive(_5);                 // scope 0 at $DIR/simplify-arm.rs:19:13: 19:14
--         _5 = ((_1 as Err).0: i32);       // scope 0 at $DIR/simplify-arm.rs:19:13: 19:14
--         StorageLive(_6);                 // scope 2 at $DIR/simplify-arm.rs:19:23: 19:24
--         _6 = _5;                         // scope 2 at $DIR/simplify-arm.rs:19:23: 19:24
--         ((_0 as Err).0: i32) = move _6;  // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
--         discriminant(_0) = 1;            // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
--         StorageDead(_6);                 // scope 2 at $DIR/simplify-arm.rs:19:24: 19:25
--         StorageDead(_5);                 // scope 0 at $DIR/simplify-arm.rs:19:25: 19:26
-+         _0 = move _1;                    // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
+          StorageLive(_5);                 // scope 0 at $DIR/simplify-arm.rs:19:13: 19:14
+          _5 = ((_1 as Err).0: i32);       // scope 0 at $DIR/simplify-arm.rs:19:13: 19:14
+          StorageLive(_6);                 // scope 2 at $DIR/simplify-arm.rs:19:23: 19:24
+          _6 = _5;                         // scope 2 at $DIR/simplify-arm.rs:19:23: 19:24
+          ((_0 as Err).0: i32) = move _6;  // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
+          discriminant(_0) = 1;            // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
+          StorageDead(_6);                 // scope 2 at $DIR/simplify-arm.rs:19:24: 19:25
+          StorageDead(_5);                 // scope 0 at $DIR/simplify-arm.rs:19:25: 19:26
           goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
       }
   
@@ -39,15 +38,14 @@
       }
   
       bb3: {
--         StorageLive(_3);                 // scope 0 at $DIR/simplify-arm.rs:18:12: 18:13
--         _3 = ((_1 as Ok).0: u8);         // scope 0 at $DIR/simplify-arm.rs:18:12: 18:13
--         StorageLive(_4);                 // scope 1 at $DIR/simplify-arm.rs:18:21: 18:22
--         _4 = _3;                         // scope 1 at $DIR/simplify-arm.rs:18:21: 18:22
--         ((_0 as Ok).0: u8) = move _4;    // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
--         discriminant(_0) = 0;            // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
--         StorageDead(_4);                 // scope 1 at $DIR/simplify-arm.rs:18:22: 18:23
--         StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:18:23: 18:24
-+         _0 = move _1;                    // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
+          StorageLive(_3);                 // scope 0 at $DIR/simplify-arm.rs:18:12: 18:13
+          _3 = ((_1 as Ok).0: u8);         // scope 0 at $DIR/simplify-arm.rs:18:12: 18:13
+          StorageLive(_4);                 // scope 1 at $DIR/simplify-arm.rs:18:21: 18:22
+          _4 = _3;                         // scope 1 at $DIR/simplify-arm.rs:18:21: 18:22
+          ((_0 as Ok).0: u8) = move _4;    // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
+          discriminant(_0) = 0;            // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
+          StorageDead(_4);                 // scope 1 at $DIR/simplify-arm.rs:18:22: 18:23
+          StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:18:23: 18:24
           goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
       }
   
diff --git a/src/test/mir-opt/simplify-arm/rustc.id_result.SimplifyBranchSame.diff b/src/test/mir-opt/simplify-arm/rustc.id_result.SimplifyBranchSame.diff
index 9d1ff22dc51..e8286516261 100644
--- a/src/test/mir-opt/simplify-arm/rustc.id_result.SimplifyBranchSame.diff
+++ b/src/test/mir-opt/simplify-arm/rustc.id_result.SimplifyBranchSame.diff
@@ -18,27 +18,38 @@
   
       bb0: {
           _2 = discriminant(_1);           // scope 0 at $DIR/simplify-arm.rs:18:9: 18:14
--         switchInt(move _2) -> [0isize: bb3, 1isize: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify-arm.rs:18:9: 18:14
-+         goto -> bb1;                     // scope 0 at $DIR/simplify-arm.rs:18:9: 18:14
+          switchInt(move _2) -> [0isize: bb3, 1isize: bb1, otherwise: bb2]; // scope 0 at $DIR/simplify-arm.rs:18:9: 18:14
       }
   
       bb1: {
--         _0 = move _1;                    // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
--         goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
--     }
-- 
--     bb2: {
--         unreachable;                     // scope 0 at $DIR/simplify-arm.rs:17:11: 17:12
--     }
-- 
--     bb3: {
-          _0 = move _1;                    // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
--         goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
-+         goto -> bb2;                     // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
+          StorageLive(_5);                 // scope 0 at $DIR/simplify-arm.rs:19:13: 19:14
+          _5 = ((_1 as Err).0: i32);       // scope 0 at $DIR/simplify-arm.rs:19:13: 19:14
+          StorageLive(_6);                 // scope 2 at $DIR/simplify-arm.rs:19:23: 19:24
+          _6 = _5;                         // scope 2 at $DIR/simplify-arm.rs:19:23: 19:24
+          ((_0 as Err).0: i32) = move _6;  // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
+          discriminant(_0) = 1;            // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
+          StorageDead(_6);                 // scope 2 at $DIR/simplify-arm.rs:19:24: 19:25
+          StorageDead(_5);                 // scope 0 at $DIR/simplify-arm.rs:19:25: 19:26
+          goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
       }
   
--     bb4: {
-+     bb2: {
+      bb2: {
+          unreachable;                     // scope 0 at $DIR/simplify-arm.rs:17:11: 17:12
+      }
+  
+      bb3: {
+          StorageLive(_3);                 // scope 0 at $DIR/simplify-arm.rs:18:12: 18:13
+          _3 = ((_1 as Ok).0: u8);         // scope 0 at $DIR/simplify-arm.rs:18:12: 18:13
+          StorageLive(_4);                 // scope 1 at $DIR/simplify-arm.rs:18:21: 18:22
+          _4 = _3;                         // scope 1 at $DIR/simplify-arm.rs:18:21: 18:22
+          ((_0 as Ok).0: u8) = move _4;    // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
+          discriminant(_0) = 0;            // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
+          StorageDead(_4);                 // scope 1 at $DIR/simplify-arm.rs:18:22: 18:23
+          StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:18:23: 18:24
+          goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
+      }
+  
+      bb4: {
           return;                          // scope 0 at $DIR/simplify-arm.rs:21:2: 21:2
       }
   }
diff --git a/src/test/mir-opt/simplify-arm/rustc.id_try.SimplifyArmIdentity.diff b/src/test/mir-opt/simplify-arm/rustc.id_try.SimplifyArmIdentity.diff
index 64b5f174300..44f475346e0 100644
--- a/src/test/mir-opt/simplify-arm/rustc.id_try.SimplifyArmIdentity.diff
+++ b/src/test/mir-opt/simplify-arm/rustc.id_try.SimplifyArmIdentity.diff
@@ -49,17 +49,16 @@
       }
   
       bb2: {
--         StorageLive(_10);                // scope 0 at $DIR/simplify-arm.rs:24:13: 24:15
--         _10 = ((_3 as Ok).0: u8);        // scope 0 at $DIR/simplify-arm.rs:24:13: 24:15
--         _2 = _10;                        // scope 5 at $DIR/simplify-arm.rs:24:13: 24:15
--         StorageDead(_10);                // scope 0 at $DIR/simplify-arm.rs:24:14: 24:15
-+         _0 = move _3;                    // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10
+          StorageLive(_10);                // scope 0 at $DIR/simplify-arm.rs:24:13: 24:15
+          _10 = ((_3 as Ok).0: u8);        // scope 0 at $DIR/simplify-arm.rs:24:13: 24:15
+          _2 = _10;                        // scope 5 at $DIR/simplify-arm.rs:24:13: 24:15
+          StorageDead(_10);                // scope 0 at $DIR/simplify-arm.rs:24:14: 24:15
           StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:24:15: 24:16
--         StorageLive(_11);                // scope 1 at $DIR/simplify-arm.rs:25:8: 25:9
--         _11 = _2;                        // scope 1 at $DIR/simplify-arm.rs:25:8: 25:9
--         ((_0 as Ok).0: u8) = move _11;   // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10
--         discriminant(_0) = 0;            // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10
--         StorageDead(_11);                // scope 1 at $DIR/simplify-arm.rs:25:9: 25:10
+          StorageLive(_11);                // scope 1 at $DIR/simplify-arm.rs:25:8: 25:9
+          _11 = _2;                        // scope 1 at $DIR/simplify-arm.rs:25:8: 25:9
+          ((_0 as Ok).0: u8) = move _11;   // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10
+          discriminant(_0) = 0;            // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10
+          StorageDead(_11);                // scope 1 at $DIR/simplify-arm.rs:25:9: 25:10
           StorageDead(_2);                 // scope 0 at $DIR/simplify-arm.rs:26:1: 26:2
           goto -> bb5;                     // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2
       }
diff --git a/src/test/mir-opt/simplify-arm/rustc.id_try.SimplifyBranchSame.diff b/src/test/mir-opt/simplify-arm/rustc.id_try.SimplifyBranchSame.diff
index 01f57bec71a..c91c55dfb04 100644
--- a/src/test/mir-opt/simplify-arm/rustc.id_try.SimplifyBranchSame.diff
+++ b/src/test/mir-opt/simplify-arm/rustc.id_try.SimplifyBranchSame.diff
@@ -49,8 +49,16 @@
       }
   
       bb2: {
-          _0 = move _3;                    // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10
+          StorageLive(_10);                // scope 0 at $DIR/simplify-arm.rs:24:13: 24:15
+          _10 = ((_3 as Ok).0: u8);        // scope 0 at $DIR/simplify-arm.rs:24:13: 24:15
+          _2 = _10;                        // scope 5 at $DIR/simplify-arm.rs:24:13: 24:15
+          StorageDead(_10);                // scope 0 at $DIR/simplify-arm.rs:24:14: 24:15
           StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:24:15: 24:16
+          StorageLive(_11);                // scope 1 at $DIR/simplify-arm.rs:25:8: 25:9
+          _11 = _2;                        // scope 1 at $DIR/simplify-arm.rs:25:8: 25:9
+          ((_0 as Ok).0: u8) = move _11;   // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10
+          discriminant(_0) = 0;            // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10
+          StorageDead(_11);                // scope 1 at $DIR/simplify-arm.rs:25:9: 25:10
           StorageDead(_2);                 // scope 0 at $DIR/simplify-arm.rs:26:1: 26:2
           goto -> bb5;                     // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2
       }
diff --git a/src/test/mir-opt/simplify_try_if_let/rustc.{{impl}}-append.SimplifyArmIdentity.diff b/src/test/mir-opt/simplify_try_if_let/rustc.{{impl}}-append.SimplifyArmIdentity.diff
index 6ccec937b9b..7d3537d0943 100644
--- a/src/test/mir-opt/simplify_try_if_let/rustc.{{impl}}-append.SimplifyArmIdentity.diff
+++ b/src/test/mir-opt/simplify_try_if_let/rustc.{{impl}}-append.SimplifyArmIdentity.diff
@@ -80,12 +80,11 @@
           StorageLive(_8);                 // scope 1 at $DIR/simplify_try_if_let.rs:26:29: 26:39
           _8 = ((_5 as Some).0: std::ptr::NonNull<Node>); // scope 1 at $DIR/simplify_try_if_let.rs:26:29: 26:39
           StorageLive(_9);                 // scope 3 at $DIR/simplify_try_if_let.rs:28:46: 28:62
--         StorageLive(_10);                // scope 3 at $DIR/simplify_try_if_let.rs:28:51: 28:61
--         _10 = _8;                        // scope 3 at $DIR/simplify_try_if_let.rs:28:51: 28:61
--         ((_9 as Some).0: std::ptr::NonNull<Node>) = move _10; // scope 3 at $DIR/simplify_try_if_let.rs:28:46: 28:62
--         discriminant(_9) = 1;            // scope 3 at $DIR/simplify_try_if_let.rs:28:46: 28:62
--         StorageDead(_10);                // scope 3 at $DIR/simplify_try_if_let.rs:28:61: 28:62
-+         _9 = move _5;                    // scope 3 at $DIR/simplify_try_if_let.rs:28:46: 28:62
+          StorageLive(_10);                // scope 3 at $DIR/simplify_try_if_let.rs:28:51: 28:61
+          _10 = _8;                        // scope 3 at $DIR/simplify_try_if_let.rs:28:51: 28:61
+          ((_9 as Some).0: std::ptr::NonNull<Node>) = move _10; // scope 3 at $DIR/simplify_try_if_let.rs:28:46: 28:62
+          discriminant(_9) = 1;            // scope 3 at $DIR/simplify_try_if_let.rs:28:46: 28:62
+          StorageDead(_10);                // scope 3 at $DIR/simplify_try_if_let.rs:28:61: 28:62
           StorageLive(_11);                // scope 3 at $DIR/simplify_try_if_let.rs:28:25: 28:38
           StorageLive(_12);                // scope 3 at $DIR/simplify_try_if_let.rs:28:25: 28:29
           _12 = &mut _4;                   // scope 3 at $DIR/simplify_try_if_let.rs:28:25: 28:29