Rollup merge of #103016 - nbdd0121:enum, r=pnkfelix

Ensure enum cast moves Fix #102389 r? `@pnkfelix`
rust-lang · Oct 13, 2022 · f6cc372 · f6cc372
2 parents 300b8fb + 4a25a49
commit f6cc372
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Showing 8 changed files with 67 additions and 26 deletions.
diff --git a/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs b/compiler/rustc_mir_build/src/build/expr/as_rvalue.rs
@@ -197,13 +197,13 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 // create all the steps directly in MIR with operations all backends need to support anyway.
                 let (source, ty) = if let ty::Adt(adt_def, ..) = source.ty.kind() && adt_def.is_enum() {
                     let discr_ty = adt_def.repr().discr_type().to_ty(this.tcx);
-                    let place = unpack!(block = this.as_place(block, source));
+                    let temp = unpack!(block = this.as_temp(block, scope, source, Mutability::Not));
                     let discr = this.temp(discr_ty, source.span);
                     this.cfg.push_assign(
                         block,
                         source_info,
                         discr,
-                        Rvalue::Discriminant(place),
+                        Rvalue::Discriminant(temp.into()),
                     );
 
                     (Operand::Move(discr), discr_ty)

diff --git a/src/test/mir-opt/enum_cast.bar.mir_map.0.mir b/src/test/mir-opt/enum_cast.bar.mir_map.0.mir
@@ -3,11 +3,15 @@
 fn bar(_1: Bar) -> usize {
     debug bar => _1;                     // in scope 0 at $DIR/enum_cast.rs:+0:8: +0:11
     let mut _0: usize;                   // return place in scope 0 at $DIR/enum_cast.rs:+0:21: +0:26
-    let mut _2: isize;                   // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+    let _2: Bar;                         // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+    let mut _3: isize;                   // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
 
     bb0: {
-        _2 = discriminant(_1);           // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
-        _0 = move _2 as usize (IntToInt); // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        StorageLive(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+        _2 = move _1;                    // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+        _3 = discriminant(_2);           // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        _0 = move _3 as usize (IntToInt); // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        StorageDead(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:16: +1:17
         return;                          // scope 0 at $DIR/enum_cast.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/mir-opt/enum_cast.boo.mir_map.0.mir b/src/test/mir-opt/enum_cast.boo.mir_map.0.mir
@@ -3,11 +3,15 @@
 fn boo(_1: Boo) -> usize {
     debug boo => _1;                     // in scope 0 at $DIR/enum_cast.rs:+0:8: +0:11
     let mut _0: usize;                   // return place in scope 0 at $DIR/enum_cast.rs:+0:21: +0:26
-    let mut _2: u8;                      // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+    let _2: Boo;                         // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+    let mut _3: u8;                      // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
 
     bb0: {
-        _2 = discriminant(_1);           // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
-        _0 = move _2 as usize (IntToInt); // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        StorageLive(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+        _2 = move _1;                    // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+        _3 = discriminant(_2);           // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        _0 = move _3 as usize (IntToInt); // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        StorageDead(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:16: +1:17
         return;                          // scope 0 at $DIR/enum_cast.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/mir-opt/enum_cast.droppy.mir_map.0.mir b/src/test/mir-opt/enum_cast.droppy.mir_map.0.mir
@@ -4,8 +4,9 @@ fn droppy() -> () {
     let mut _0: ();                      // return place in scope 0 at $DIR/enum_cast.rs:+0:13: +0:13
     let _1: ();                          // in scope 0 at $DIR/enum_cast.rs:+1:5: +6:6
     let _2: Droppy;                      // in scope 0 at $DIR/enum_cast.rs:+2:13: +2:14
-    let mut _4: isize;                   // in scope 0 at $DIR/enum_cast.rs:+5:17: +5:18
-    let _5: Droppy;                      // in scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
+    let _4: Droppy;                      // in scope 0 at $DIR/enum_cast.rs:+5:17: +5:18
+    let mut _5: isize;                   // in scope 0 at $DIR/enum_cast.rs:+5:17: +5:18
+    let _6: Droppy;                      // in scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
     scope 1 {
         debug x => _2;                   // in scope 1 at $DIR/enum_cast.rs:+2:13: +2:14
         scope 2 {
@@ -16,7 +17,7 @@ fn droppy() -> () {
         }
     }
     scope 4 {
-        debug z => _5;                   // in scope 4 at $DIR/enum_cast.rs:+7:9: +7:10
+        debug z => _6;                   // in scope 4 at $DIR/enum_cast.rs:+7:9: +7:10
     }
 
     bb0: {
@@ -25,30 +26,41 @@ fn droppy() -> () {
         _2 = Droppy::C;                  // scope 0 at $DIR/enum_cast.rs:+2:17: +2:26
         FakeRead(ForLet(None), _2);      // scope 0 at $DIR/enum_cast.rs:+2:13: +2:14
         StorageLive(_3);                 // scope 3 at $DIR/enum_cast.rs:+5:13: +5:14
-        _4 = discriminant(_2);           // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
-        _3 = move _4 as usize (IntToInt); // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
+        StorageLive(_4);                 // scope 3 at $DIR/enum_cast.rs:+5:17: +5:18
+        _4 = move _2;                    // scope 3 at $DIR/enum_cast.rs:+5:17: +5:18
+        _5 = discriminant(_4);           // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
+        _3 = move _5 as usize (IntToInt); // scope 3 at $DIR/enum_cast.rs:+5:17: +5:27
+        drop(_4) -> [return: bb1, unwind: bb4]; // scope 3 at $DIR/enum_cast.rs:+5:26: +5:27
+    }
+
+    bb1: {
+        StorageDead(_4);                 // scope 3 at $DIR/enum_cast.rs:+5:26: +5:27
         FakeRead(ForLet(None), _3);      // scope 3 at $DIR/enum_cast.rs:+5:13: +5:14
         _1 = const ();                   // scope 0 at $DIR/enum_cast.rs:+1:5: +6:6
         StorageDead(_3);                 // scope 1 at $DIR/enum_cast.rs:+6:5: +6:6
-        drop(_2) -> [return: bb1, unwind: bb3]; // scope 0 at $DIR/enum_cast.rs:+6:5: +6:6
+        drop(_2) -> [return: bb2, unwind: bb5]; // scope 0 at $DIR/enum_cast.rs:+6:5: +6:6
     }
 
-    bb1: {
+    bb2: {
         StorageDead(_2);                 // scope 0 at $DIR/enum_cast.rs:+6:5: +6:6
         StorageDead(_1);                 // scope 0 at $DIR/enum_cast.rs:+6:5: +6:6
-        StorageLive(_5);                 // scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
-        _5 = Droppy::B;                  // scope 0 at $DIR/enum_cast.rs:+7:13: +7:22
-        FakeRead(ForLet(None), _5);      // scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
+        StorageLive(_6);                 // scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
+        _6 = Droppy::B;                  // scope 0 at $DIR/enum_cast.rs:+7:13: +7:22
+        FakeRead(ForLet(None), _6);      // scope 0 at $DIR/enum_cast.rs:+7:9: +7:10
         _0 = const ();                   // scope 0 at $DIR/enum_cast.rs:+0:13: +8:2
-        drop(_5) -> [return: bb2, unwind: bb3]; // scope 0 at $DIR/enum_cast.rs:+8:1: +8:2
+        drop(_6) -> [return: bb3, unwind: bb5]; // scope 0 at $DIR/enum_cast.rs:+8:1: +8:2
     }
 
-    bb2: {
-        StorageDead(_5);                 // scope 0 at $DIR/enum_cast.rs:+8:1: +8:2
+    bb3: {
+        StorageDead(_6);                 // scope 0 at $DIR/enum_cast.rs:+8:1: +8:2
         return;                          // scope 0 at $DIR/enum_cast.rs:+8:2: +8:2
     }
 
-    bb3 (cleanup): {
+    bb4 (cleanup): {
+        drop(_2) -> bb5;                 // scope 0 at $DIR/enum_cast.rs:+6:5: +6:6
+    }
+
+    bb5 (cleanup): {
         resume;                          // scope 0 at $DIR/enum_cast.rs:+0:1: +8:2
     }
 }
diff --git a/src/test/mir-opt/enum_cast.foo.mir_map.0.mir b/src/test/mir-opt/enum_cast.foo.mir_map.0.mir
@@ -3,11 +3,15 @@
 fn foo(_1: Foo) -> usize {
     debug foo => _1;                     // in scope 0 at $DIR/enum_cast.rs:+0:8: +0:11
     let mut _0: usize;                   // return place in scope 0 at $DIR/enum_cast.rs:+0:21: +0:26
-    let mut _2: isize;                   // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+    let _2: Foo;                         // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+    let mut _3: isize;                   // in scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
 
     bb0: {
-        _2 = discriminant(_1);           // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
-        _0 = move _2 as usize (IntToInt); // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        StorageLive(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+        _2 = move _1;                    // scope 0 at $DIR/enum_cast.rs:+1:5: +1:8
+        _3 = discriminant(_2);           // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        _0 = move _3 as usize (IntToInt); // scope 0 at $DIR/enum_cast.rs:+1:5: +1:17
+        StorageDead(_2);                 // scope 0 at $DIR/enum_cast.rs:+1:16: +1:17
         return;                          // scope 0 at $DIR/enum_cast.rs:+2:2: +2:2
     }
 }
diff --git a/src/test/run-pass-valgrind/cast-enum-with-dtor.rs b/src/test/run-pass-valgrind/cast-enum-with-dtor.rs
@@ -28,7 +28,7 @@ fn main() {
     {
         let e = E::C;
         assert_eq!(e as u32, 2);
-        assert_eq!(FLAG.load(Ordering::SeqCst), 0);
+        assert_eq!(FLAG.load(Ordering::SeqCst), 1);
     }
     assert_eq!(FLAG.load(Ordering::SeqCst), 1);
 }
diff --git a/src/test/ui/mir/issue-102389.rs b/src/test/ui/mir/issue-102389.rs
@@ -0,0 +1,8 @@
+enum Enum { A, B, C }
+
+fn func(inbounds: &Enum, array: &[i16; 3]) -> i16 {
+    array[*inbounds as usize]
+    //~^ ERROR [E0507]
+}
+
+fn main() {}
diff --git a/src/test/ui/mir/issue-102389.stderr b/src/test/ui/mir/issue-102389.stderr
@@ -0,0 +1,9 @@
+error[E0507]: cannot move out of `*inbounds` which is behind a shared reference
+  --> $DIR/issue-102389.rs:4:11
+   |
+LL |     array[*inbounds as usize]
+   |           ^^^^^^^^^ move occurs because `*inbounds` has type `Enum`, which does not implement the `Copy` trait
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0507`.