Only run return terminator opt if mir-opt-level=3

alarsyo · alarsyo · commit b860a545de07 · 2020-08-29T17:18:36.000+02:00
diff --git a/src/librustc_mir/transform/multiple_return_terminators.rs b/src/librustc_mir/transform/multiple_return_terminators.rs
@@ -9,7 +9,11 @@ use rustc_middle::ty::TyCtxt;
 pub struct MultipleReturnTerminators;
 
 impl<'tcx> MirPass<'tcx> for MultipleReturnTerminators {
-    fn run_pass(&self, _: TyCtxt<'tcx>, _: MirSource<'tcx>, body: &mut Body<'tcx>) {
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, _: MirSource<'tcx>, body: &mut Body<'tcx>) {
+        if tcx.sess.opts.debugging_opts.mir_opt_level < 3 {
+            return;
+        }
+
         // find basic blocks with no statement and a return terminator
         let mut bbs_simple_returns = BitSet::new_empty(body.basic_blocks().len());
         let bbs = body.basic_blocks_mut();
diff --git a/src/test/mir-opt/multiple_return_terminators.rs b/src/test/mir-opt/multiple_return_terminators.rs
@@ -1,3 +1,4 @@
+// compile-flags: -Z mir-opt-level=3
 // EMIT_MIR multiple_return_terminators.test.MultipleReturnTerminators.diff
 
 fn test(x: bool) {
diff --git a/src/test/mir-opt/multiple_return_terminators.test.MultipleReturnTerminators.diff b/src/test/mir-opt/multiple_return_terminators.test.MultipleReturnTerminators.diff
@@ -2,27 +2,27 @@
 + // MIR for `test` after MultipleReturnTerminators
   
   fn test(_1: bool) -> () {
-      debug x => _1;                       // in scope 0 at $DIR/multiple_return_terminators.rs:3:9: 3:10
-      let mut _0: ();                      // return place in scope 0 at $DIR/multiple_return_terminators.rs:3:18: 3:18
+      debug x => _1;                       // in scope 0 at $DIR/multiple_return_terminators.rs:4:9: 4:10
+      let mut _0: ();                      // return place in scope 0 at $DIR/multiple_return_terminators.rs:4:18: 4:18
   
       bb0: {
-          switchInt(_1) -> [false: bb1, otherwise: bb2]; // scope 0 at $DIR/multiple_return_terminators.rs:4:5: 8:6
+          switchInt(_1) -> [false: bb1, otherwise: bb2]; // scope 0 at $DIR/multiple_return_terminators.rs:5:5: 9:6
       }
   
       bb1: {
-          _0 = const ();                   // scope 0 at $DIR/multiple_return_terminators.rs:6:12: 8:6
--         goto -> bb3;                     // scope 0 at $DIR/multiple_return_terminators.rs:4:5: 8:6
-+         return;                          // scope 0 at $DIR/multiple_return_terminators.rs:4:5: 8:6
+          _0 = const ();                   // scope 0 at $DIR/multiple_return_terminators.rs:7:12: 9:6
+-         goto -> bb3;                     // scope 0 at $DIR/multiple_return_terminators.rs:5:5: 9:6
++         return;                          // scope 0 at $DIR/multiple_return_terminators.rs:5:5: 9:6
       }
   
       bb2: {
-          _0 = const ();                   // scope 0 at $DIR/multiple_return_terminators.rs:4:10: 6:6
--         goto -> bb3;                     // scope 0 at $DIR/multiple_return_terminators.rs:4:5: 8:6
+          _0 = const ();                   // scope 0 at $DIR/multiple_return_terminators.rs:5:10: 7:6
+-         goto -> bb3;                     // scope 0 at $DIR/multiple_return_terminators.rs:5:5: 9:6
 -     }
 - 
 -     bb3: {
--         return;                          // scope 0 at $DIR/multiple_return_terminators.rs:9:2: 9:2
-+         return;                          // scope 0 at $DIR/multiple_return_terminators.rs:4:5: 8:6
+-         return;                          // scope 0 at $DIR/multiple_return_terminators.rs:10:2: 10:2
++         return;                          // scope 0 at $DIR/multiple_return_terminators.rs:5:5: 9:6
       }
   }
   
diff --git a/src/test/mir-opt/simplify_arm.id.SimplifyArmIdentity.diff b/src/test/mir-opt/simplify_arm.id.SimplifyArmIdentity.diff
@@ -19,7 +19,7 @@
   
       bb1: {
           discriminant(_0) = 0;            // scope 0 at $DIR/simplify-arm.rs:12:17: 12:21
-          return;                          // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
+          goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
       }
   
       bb2: {
@@ -36,7 +36,11 @@
 -         StorageDead(_4);                 // scope 1 at $DIR/simplify-arm.rs:11:26: 11:27
 -         StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:11:26: 11:27
 +         _0 = move _1;                    // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
-          return;                          // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
+          goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
+      }
+  
+      bb4: {
+          return;                          // scope 0 at $DIR/simplify-arm.rs:14:2: 14:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_arm.id.SimplifyBranchSame.diff b/src/test/mir-opt/simplify_arm.id.SimplifyBranchSame.diff
@@ -19,7 +19,7 @@
   
       bb1: {
 -         discriminant(_0) = 0;            // scope 0 at $DIR/simplify-arm.rs:12:17: 12:21
--         return;                          // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
+-         goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
 -     }
 - 
 -     bb2: {
@@ -28,7 +28,13 @@
 - 
 -     bb3: {
           _0 = move _1;                    // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27
-          return;                          // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
+-         goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
++         goto -> bb2;                     // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6
+      }
+  
+-     bb4: {
++     bb2: {
+          return;                          // scope 0 at $DIR/simplify-arm.rs:14:2: 14:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_arm.id_result.SimplifyArmIdentity.diff b/src/test/mir-opt/simplify_arm.id_result.SimplifyArmIdentity.diff
@@ -33,7 +33,7 @@
 -         StorageDead(_6);                 // scope 2 at $DIR/simplify-arm.rs:19:24: 19:25
 -         StorageDead(_5);                 // scope 0 at $DIR/simplify-arm.rs:19:24: 19:25
 +         _0 = move _1;                    // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
-          return;                          // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
+          goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
       }
   
       bb2: {
@@ -50,7 +50,11 @@
 -         StorageDead(_4);                 // scope 1 at $DIR/simplify-arm.rs:18:22: 18:23
 -         StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:18:22: 18:23
 +         _0 = move _1;                    // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
-          return;                          // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
+          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.id_result.SimplifyBranchSame.diff b/src/test/mir-opt/simplify_arm.id_result.SimplifyBranchSame.diff
@@ -24,7 +24,7 @@
   
       bb1: {
 -         _0 = move _1;                    // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25
--         return;                          // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
+-         goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
 -     }
 - 
 -     bb2: {
@@ -33,7 +33,13 @@
 - 
 -     bb3: {
           _0 = move _1;                    // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23
-          return;                          // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6
+-         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
+      }
+  
+-     bb4: {
++     bb2: {
+          return;                          // scope 0 at $DIR/simplify-arm.rs:21:2: 21:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_arm.id_try.SimplifyArmIdentity.diff b/src/test/mir-opt/simplify_arm.id_try.SimplifyArmIdentity.diff
@@ -67,7 +67,7 @@
 -         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
-          return;                          // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2
+          goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2
       }
   
       bb2: {
@@ -92,7 +92,11 @@
 +         _0 = move _3;                    // scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
           StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:24:15: 24:16
           StorageDead(_2);                 // scope 0 at $DIR/simplify-arm.rs:26:1: 26:2
-          return;                          // scope 0 at $DIR/simplify-arm.rs:24:14: 24:15
+          goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:24:14: 24:15
+      }
+  
+      bb4: {
+          return;                          // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_arm.id_try.SimplifyBranchSame.diff b/src/test/mir-opt/simplify_arm.id_try.SimplifyBranchSame.diff
@@ -54,18 +54,23 @@
           _0 = move _3;                    // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10
           StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:24:15: 24:16
           StorageDead(_2);                 // scope 0 at $DIR/simplify-arm.rs:26:1: 26:2
-          return;                          // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2
--     }
-- 
--     bb2: {
+-         goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2
++         goto -> bb2;                     // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2
+      }
+  
+      bb2: {
 -         unreachable;                     // scope 0 at $DIR/simplify-arm.rs:24:13: 24:15
 -     }
 - 
 -     bb3: {
 -         _0 = move _3;                    // scope 8 at $SRC_DIR/core/src/result.rs:LL:COL
 -         StorageDead(_3);                 // scope 0 at $DIR/simplify-arm.rs:24:15: 24:16
 -         StorageDead(_2);                 // scope 0 at $DIR/simplify-arm.rs:26:1: 26:2
--         return;                          // scope 0 at $DIR/simplify-arm.rs:24:14: 24:15
+-         goto -> bb4;                     // scope 0 at $DIR/simplify-arm.rs:24:14: 24:15
+-     }
+- 
+-     bb4: {
+          return;                          // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2
       }
   }
   
diff --git a/src/test/mir-opt/simplify_try_if_let.{{impl}}-append.SimplifyArmIdentity.diff b/src/test/mir-opt/simplify_try_if_let.{{impl}}-append.SimplifyArmIdentity.diff
@@ -47,7 +47,7 @@
   
       bb3: {
           _0 = const ();                   // scope 0 at $DIR/simplify_try_if_let.rs:22:21: 22:24
-          return;                          // scope 0 at $DIR/simplify_try_if_let.rs:21:9: 32:10
+          goto -> bb9;                     // scope 0 at $DIR/simplify_try_if_let.rs:21:9: 32:10
       }
   
       bb4: {
@@ -92,7 +92,11 @@
       bb8: {
           StorageDead(_5);                 // scope 1 at $DIR/simplify_try_if_let.rs:31:13: 31:14
           StorageDead(_4);                 // scope 0 at $DIR/simplify_try_if_let.rs:31:13: 31:14
-          return;                          // scope 0 at $DIR/simplify_try_if_let.rs:21:9: 32:10
+          goto -> bb9;                     // scope 0 at $DIR/simplify_try_if_let.rs:21:9: 32:10
+      }
+  
+      bb9: {
+          return;                          // scope 0 at $DIR/simplify_try_if_let.rs:33:6: 33:6
       }
   }
   

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,4 @@`
	`1`	`+// compile-flags: -Z mir-opt-level=3`
`1`	`2`	`// EMIT_MIR multiple_return_terminators.test.MultipleReturnTerminators.diff`
`2`	`3`
`3`	`4`	`fn test(x: bool) {`
Original file line number	Diff line number	Diff line change
`@@ -19,7 +19,7 @@`
`19`	`19`
`20`	`20`	`bb1: {`
`21`	`21`	`discriminant(_0) = 0; // scope 0 at $DIR/simplify-arm.rs:12:17: 12:21`
`22`		`- return; // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6`
	`22`	`+ goto -> bb4; // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6`
`23`	`23`	`}`
`24`	`24`
`25`	`25`	`bb2: {`
`@@ -36,7 +36,11 @@`
`36`	`36`	`- StorageDead(_4); // scope 1 at $DIR/simplify-arm.rs:11:26: 11:27`
`37`	`37`	`- StorageDead(_3); // scope 0 at $DIR/simplify-arm.rs:11:26: 11:27`
`38`	`38`	`+ _0 = move _1; // scope 1 at $DIR/simplify-arm.rs:11:20: 11:27`
`39`		`- return; // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6`
	`39`	`+ goto -> bb4; // scope 0 at $DIR/simplify-arm.rs:10:5: 13:6`
	`40`	`+ }`
	`41`	`+`
	`42`	`+ bb4: {`
	`43`	`+ return; // scope 0 at $DIR/simplify-arm.rs:14:2: 14:2`
`40`	`44`	`}`
`41`	`45`	`}`
`42`	`46`
Original file line number	Diff line number	Diff line change
`@@ -33,7 +33,7 @@`
`33`	`33`	`- StorageDead(_6); // scope 2 at $DIR/simplify-arm.rs:19:24: 19:25`
`34`	`34`	`- StorageDead(_5); // scope 0 at $DIR/simplify-arm.rs:19:24: 19:25`
`35`	`35`	`+ _0 = move _1; // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25`
`36`		`- return; // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6`
	`36`	`+ goto -> bb4; // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6`
`37`	`37`	`}`
`38`	`38`
`39`	`39`	`bb2: {`
`@@ -50,7 +50,11 @@`
`50`	`50`	`- StorageDead(_4); // scope 1 at $DIR/simplify-arm.rs:18:22: 18:23`
`51`	`51`	`- StorageDead(_3); // scope 0 at $DIR/simplify-arm.rs:18:22: 18:23`
`52`	`52`	`+ _0 = move _1; // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23`
`53`		`- return; // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6`
	`53`	`+ goto -> bb4; // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6`
	`54`	`+ }`
	`55`	`+`
	`56`	`+ bb4: {`
	`57`	`+ return; // scope 0 at $DIR/simplify-arm.rs:21:2: 21:2`
`54`	`58`	`}`
`55`	`59`	`}`
`56`	`60`
Original file line number	Diff line number	Diff line change
`@@ -24,7 +24,7 @@`
`24`	`24`
`25`	`25`	`bb1: {`
`26`	`26`	`- _0 = move _1; // scope 2 at $DIR/simplify-arm.rs:19:19: 19:25`
`27`		`-- return; // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6`
	`27`	`+- goto -> bb4; // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6`
`28`	`28`	`- }`
`29`	`29`	`-`
`30`	`30`	`- bb2: {`
`@@ -33,7 +33,13 @@`
`33`	`33`	`-`
`34`	`34`	`- bb3: {`
`35`	`35`	`_0 = move _1; // scope 1 at $DIR/simplify-arm.rs:18:18: 18:23`
`36`		`- return; // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6`
	`36`	`+- goto -> bb4; // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6`
	`37`	`++ goto -> bb2; // scope 0 at $DIR/simplify-arm.rs:17:5: 20:6`
	`38`	`+ }`
	`39`	`+`
	`40`	`+- bb4: {`
	`41`	`++ bb2: {`
	`42`	`+ return; // scope 0 at $DIR/simplify-arm.rs:21:2: 21:2`
`37`	`43`	`}`
`38`	`44`	`}`
`39`	`45`
Original file line number	Diff line number	Diff line change
`@@ -67,7 +67,7 @@`
`67`	`67`	`- discriminant(_0) = 0; // scope 1 at $DIR/simplify-arm.rs:25:5: 25:10`
`68`	`68`	`- StorageDead(_11); // scope 1 at $DIR/simplify-arm.rs:25:9: 25:10`
`69`	`69`	`StorageDead(_2); // scope 0 at $DIR/simplify-arm.rs:26:1: 26:2`
`70`		`- return; // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2`
	`70`	`+ goto -> bb4; // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2`
`71`	`71`	`}`
`72`	`72`
`73`	`73`	`bb2: {`
`@@ -92,7 +92,11 @@`
`92`	`92`	`+ _0 = move _3; // scope 8 at $SRC_DIR/core/src/result.rs:LL:COL`
`93`	`93`	`StorageDead(_3); // scope 0 at $DIR/simplify-arm.rs:24:15: 24:16`
`94`	`94`	`StorageDead(_2); // scope 0 at $DIR/simplify-arm.rs:26:1: 26:2`
`95`		`- return; // scope 0 at $DIR/simplify-arm.rs:24:14: 24:15`
	`95`	`+ goto -> bb4; // scope 0 at $DIR/simplify-arm.rs:24:14: 24:15`
	`96`	`+ }`
	`97`	`+`
	`98`	`+ bb4: {`
	`99`	`+ return; // scope 0 at $DIR/simplify-arm.rs:26:2: 26:2`
`96`	`100`	`}`
`97`	`101`	`}`
`98`	`102`
Original file line number	Diff line number	Diff line change
`@@ -47,7 +47,7 @@`
`47`	`47`
`48`	`48`	`bb3: {`
`49`	`49`	`_0 = const (); // scope 0 at $DIR/simplify_try_if_let.rs:22:21: 22:24`
`50`		`- return; // scope 0 at $DIR/simplify_try_if_let.rs:21:9: 32:10`
	`50`	`+ goto -> bb9; // scope 0 at $DIR/simplify_try_if_let.rs:21:9: 32:10`
`51`	`51`	`}`
`52`	`52`
`53`	`53`	`bb4: {`
`@@ -92,7 +92,11 @@`
`92`	`92`	`bb8: {`
`93`	`93`	`StorageDead(_5); // scope 1 at $DIR/simplify_try_if_let.rs:31:13: 31:14`
`94`	`94`	`StorageDead(_4); // scope 0 at $DIR/simplify_try_if_let.rs:31:13: 31:14`
`95`		`- return; // scope 0 at $DIR/simplify_try_if_let.rs:21:9: 32:10`
	`95`	`+ goto -> bb9; // scope 0 at $DIR/simplify_try_if_let.rs:21:9: 32:10`
	`96`	`+ }`
	`97`	`+`
	`98`	`+ bb9: {`
	`99`	`+ return; // scope 0 at $DIR/simplify_try_if_let.rs:33:6: 33:6`
`96`	`100`	`}`
`97`	`101`	`}`
`98`	`102`