TB: rename Active → Unique to match paper

25 files changed, 95 insertions, 128 deletions

diff --git a/src/tools/miri/src/borrow_tracker/tree_borrows/diagnostics.rs b/src/tools/miri/src/borrow_tracker/tree_borrows/diagnostics.rs
index 7b4c533cfae..a7977cd3366 100644
--- a/src/tools/miri/src/borrow_tracker/tree_borrows/diagnostics.rs
+++ b/src/tools/miri/src/borrow_tracker/tree_borrows/diagnostics.rs
@@ -244,8 +244,8 @@ pub(super) enum TransitionError {
     ChildAccessForbidden(Permission),
     /// A protector was triggered due to an invalid transition that loses
     /// too much permissions.
-    /// For example, if a protected tag goes from `Active` to `Disabled` due
-    /// to a foreign write this will produce a `ProtectedDisabled(Active)`.
+    /// For example, if a protected tag goes from `Unique` to `Disabled` due
+    /// to a foreign write this will produce a `ProtectedDisabled(Unique)`.
     /// This kind of error can only occur on foreign accesses.
     ProtectedDisabled(Permission),
     /// Cannot deallocate because some tag in the allocation is strongly protected.
diff --git a/src/tools/miri/src/borrow_tracker/tree_borrows/perms.rs b/src/tools/miri/src/borrow_tracker/tree_borrows/perms.rs
index 390435e58d1..e21775c9f23 100644
--- a/src/tools/miri/src/borrow_tracker/tree_borrows/perms.rs
+++ b/src/tools/miri/src/borrow_tracker/tree_borrows/perms.rs
@@ -14,7 +14,7 @@ enum PermissionPriv {
     Cell,
     /// represents: a local mutable reference that has not yet been written to;
     /// allows: child reads, foreign reads;
-    /// affected by: child writes (becomes Active),
+    /// affected by: child writes (becomes Unique),
     /// rejects: foreign writes (Disabled).
     ///
     /// `ReservedFrz` is mostly for types that are `Freeze` (no interior mutability).
@@ -31,17 +31,17 @@ enum PermissionPriv {
     /// This is so that the behavior of `Reserved` adheres to the rules of `noalias`:
     /// - foreign-read then child-write is UB due to `conflicted`,
     /// - child-write then foreign-read is UB since child-write will activate and then
-    ///   foreign-read disables a protected `Active`, which is UB.
+    ///   foreign-read disables a protected `Unique`, which is UB.
     ReservedFrz { conflicted: bool },
     /// Alternative version of `ReservedFrz` made for types with interior mutability.
     /// allows: child reads, foreign reads, foreign writes (extra);
-    /// affected by: child writes (becomes Active);
+    /// affected by: child writes (becomes Unique);
     /// rejects: nothing.
     ReservedIM,
     /// represents: a unique pointer;
     /// allows: child reads, child writes;
     /// rejects: foreign reads (Frozen), foreign writes (Disabled).
-    Active,
+    Unique,
     /// represents: a shared pointer;
     /// allows: all read accesses;
     /// rejects child writes (UB), foreign writes (Disabled).
@@ -56,7 +56,7 @@ use super::foreign_access_skipping::IdempotentForeignAccess;
 
 impl PartialOrd for PermissionPriv {
     /// PermissionPriv is ordered by the reflexive transitive closure of
-    /// `Reserved(conflicted=false) < Reserved(conflicted=true) < Active < Frozen < Disabled`.
+    /// `Reserved(conflicted=false) < Reserved(conflicted=true) < Unique < Frozen < Disabled`.
     /// `Reserved` that have incompatible `ty_is_freeze` are incomparable to each other.
     /// This ordering matches the reachability by transitions, as asserted by the exhaustive test
     /// `permissionpriv_partialord_is_reachability`.
@@ -76,8 +76,8 @@ impl PartialOrd for PermissionPriv {
             (_, Disabled) => Less,
             (Frozen, _) => Greater,
             (_, Frozen) => Less,
-            (Active, _) => Greater,
-            (_, Active) => Less,
+            (Unique, _) => Greater,
+            (_, Unique) => Less,
             (ReservedIM, ReservedIM) => Equal,
             (ReservedFrz { conflicted: c1 }, ReservedFrz { conflicted: c2 }) => {
                 // `bool` is ordered such that `false <= true`, so this works as intended.
@@ -115,8 +115,8 @@ impl PermissionPriv {
             // Famously, ReservedIM survives foreign writes. It is never protected.
             ReservedIM if prot => unreachable!("Protected ReservedIM should not exist!"),
             ReservedIM => IdempotentForeignAccess::Write,
-            // Active changes on any foreign access (becomes Frozen/Disabled).
-            Active => IdempotentForeignAccess::None,
+            // Unique changes on any foreign access (becomes Frozen/Disabled).
+            Unique => IdempotentForeignAccess::None,
             // Frozen survives foreign reads, but not writes.
             Frozen => IdempotentForeignAccess::Read,
             // Disabled survives foreign reads and writes. It survives them
@@ -139,12 +139,12 @@ mod transition {
             Disabled => return None,
             // The inner data `ty_is_freeze` of `Reserved` is always irrelevant for Read
             // accesses, since the data is not being mutated. Hence the `{ .. }`.
-            readable @ (Cell | ReservedFrz { .. } | ReservedIM | Active | Frozen) => readable,
+            readable @ (Cell | ReservedFrz { .. } | ReservedIM | Unique | Frozen) => readable,
         })
     }
 
     /// A non-child node was read-accessed: keep `Reserved` but mark it as `conflicted` if it
-    /// is protected; invalidate `Active`.
+    /// is protected; invalidate `Unique`.
     fn foreign_read(state: PermissionPriv, protected: bool) -> Option<PermissionPriv> {
         Some(match state {
             // Cell ignores foreign reads.
@@ -167,10 +167,10 @@ mod transition {
                 assert!(!protected);
                 res
             }
-            Active =>
+            Unique =>
                 if protected {
                     // We wrote, someone else reads -- that's bad.
-                    // (Since Active is always initialized, this move-to-protected will mean insta-UB.)
+                    // (Since Unique is always initialized, this move-to-protected will mean insta-UB.)
                     Disabled
                 } else {
                     // We don't want to disable here to allow read-read reordering: it is crucial
@@ -180,7 +180,7 @@ mod transition {
         })
     }
 
-    /// A child node was write-accessed: `Reserved` must become `Active` to obtain
+    /// A child node was write-accessed: `Reserved` must become `Unique` to obtain
     /// write permissions, `Frozen` and `Disabled` cannot obtain such permissions and produce UB.
     fn child_write(state: PermissionPriv, protected: bool) -> Option<PermissionPriv> {
         Some(match state {
@@ -192,7 +192,7 @@ mod transition {
             ReservedFrz { conflicted: true } if protected => return None,
             // A write always activates the 2-phase borrow, even with interior
             // mutability
-            ReservedFrz { .. } | ReservedIM | Active => Active,
+            ReservedFrz { .. } | ReservedIM | Unique => Unique,
             Frozen | Disabled => return None,
         })
     }
@@ -266,8 +266,8 @@ impl Permission {
 
     /// Default initial permission of the root of a new tree at inbounds positions.
     /// Must *only* be used for the root, this is not in general an "initial" permission!
-    pub fn new_active() -> Self {
-        Self { inner: Active }
+    pub fn new_unique() -> Self {
+        Self { inner: Unique }
     }
 
     /// Default initial permission of a reborrowed mutable reference that is either
@@ -309,7 +309,7 @@ impl Permission {
             // Do not do perform access if it is a `Cell`, as this
             // can cause data races when using thread-safe data types.
             Cell => None,
-            Active => Some(AccessKind::Write),
+            Unique => Some(AccessKind::Write),
             _ => Some(AccessKind::Read),
         }
     }
@@ -344,7 +344,7 @@ impl Permission {
             (_, Cell) => false,
             // ReservedIM can be replaced by anything besides Cell.
             // ReservedIM allows all transitions, but unlike Cell, a local write
-            // to ReservedIM transitions to Active, while it is a no-op for Cell.
+            // to ReservedIM transitions to Unique, while it is a no-op for Cell.
             (ReservedIM, _) => true,
             (_, ReservedIM) => false,
             // Reserved (as parent, where conflictedness does not matter)
@@ -352,12 +352,12 @@ impl Permission {
             // since ReservedIM and Cell alone would survive foreign writes
             (ReservedFrz { .. }, _) => true,
             (_, ReservedFrz { .. }) => false,
-            // Active can not be replaced by something surviving
+            // Unique can not be replaced by something surviving
             // foreign reads and then remaining writable (i.e., Reserved*).
             // Replacing a state by itself is always okay, even if the child state is protected.
-            // Active can be replaced by Frozen, since it is not protected.
-            (Active, Active | Frozen | Disabled) => true,
-            (_, Active) => false,
+            // Unique can be replaced by Frozen, since it is not protected.
+            (Unique, Unique | Frozen | Disabled) => true,
+            (_, Unique) => false,
             // Frozen can only be replaced by Disabled (and itself).
             (Frozen, Frozen | Disabled) => true,
             (_, Frozen) => false,
@@ -410,7 +410,7 @@ pub mod diagnostics {
                     ReservedFrz { conflicted: false } => "Reserved",
                     ReservedFrz { conflicted: true } => "Reserved (conflicted)",
                     ReservedIM => "Reserved (interior mutable)",
-                    Active => "Active",
+                    Unique => "Unique",
                     Frozen => "Frozen",
                     Disabled => "Disabled",
                 }
@@ -441,7 +441,7 @@ pub mod diagnostics {
                 ReservedFrz { conflicted: false } => "Res ",
                 ReservedFrz { conflicted: true } => "ResC",
                 ReservedIM => "ReIM",
-                Active => "Act ",
+                Unique => "Act ",
                 Frozen => "Frz ",
                 Disabled => "Dis ",
             }
@@ -455,7 +455,7 @@ pub mod diagnostics {
             assert!(self.is_possible());
             assert!(!self.is_noop());
             match (self.from, self.to) {
-                (_, Active) => "the first write to a 2-phase borrowed mutable reference",
+                (_, Unique) => "the first write to a 2-phase borrowed mutable reference",
                 (_, Frozen) => "a loss of write permissions",
                 (ReservedFrz { conflicted: false }, ReservedFrz { conflicted: true }) =>
                     "a temporary loss of write permissions until function exit",
@@ -472,8 +472,8 @@ pub mod diagnostics {
         ///
         /// Irrelevant events:
         /// - modifications of write permissions when the error is related to read permissions
-        ///   (on failed reads and protected `Frozen -> Disabled`, ignore `Reserved -> Active`,
-        ///   `Reserved(conflicted=false) -> Reserved(conflicted=true)`, and `Active -> Frozen`)
+        ///   (on failed reads and protected `Frozen -> Disabled`, ignore `Reserved -> Unique`,
+        ///   `Reserved(conflicted=false) -> Reserved(conflicted=true)`, and `Unique -> Frozen`)
         /// - all transitions for attempts to deallocate strongly protected tags
         ///
         /// # Panics
@@ -481,10 +481,10 @@ pub mod diagnostics {
         /// This function assumes that its arguments apply to the same location
         /// and that they were obtained during a normal execution. It will panic otherwise.
         /// - all transitions involved in `self` and `err` should be increasing
-        ///   (Reserved < Active < Frozen < Disabled);
+        ///   (Reserved < Unique < Frozen < Disabled);
         /// - between `self` and `err` the permission should also be increasing,
         ///   so all permissions inside `err` should be greater than `self.1`;
-        /// - `Active`, `Reserved(conflicted=false)`, and `Cell` cannot cause an error
+        /// - `Unique`, `Reserved(conflicted=false)`, and `Cell` cannot cause an error
         ///   due to insufficient permissions, so `err` cannot be a `ChildAccessForbidden(_)`
         ///   of either of them;
         /// - `err` should not be `ProtectedDisabled(Disabled)`, because the protected
@@ -500,11 +500,11 @@ pub mod diagnostics {
                 TransitionError::ChildAccessForbidden(insufficient) => {
                     // Show where the permission was gained then lost,
                     // but ignore unrelated permissions.
-                    // This eliminates transitions like `Active -> Frozen`
+                    // This eliminates transitions like `Unique -> Frozen`
                     // when the error is a failed `Read`.
                     match (self.to, insufficient.inner) {
                         (Frozen, Frozen) => true,
-                        (Active, Frozen) => true,
+                        (Unique, Frozen) => true,
                         (Disabled, Disabled) => true,
                         (
                             ReservedFrz { conflicted: true, .. },
@@ -512,14 +512,14 @@ pub mod diagnostics {
                         ) => true,
                         // A pointer being `Disabled` is a strictly stronger source of
                         // errors than it being `Frozen`. If we try to access a `Disabled`,
-                        // then where it became `Frozen` (or `Active` or `Reserved`) is the least
+                        // then where it became `Frozen` (or `Unique` or `Reserved`) is the least
                         // of our concerns for now.
-                        (ReservedFrz { conflicted: true } | Active | Frozen, Disabled) => false,
+                        (ReservedFrz { conflicted: true } | Unique | Frozen, Disabled) => false,
                         (ReservedFrz { conflicted: true }, Frozen) => false,
 
-                        // `Active`, `Reserved`, and `Cell` have all permissions, so a
-                        // `ChildAccessForbidden(Reserved | Active)` can never exist.
-                        (_, Active) | (_, ReservedFrz { conflicted: false }) | (_, Cell) =>
+                        // `Unique`, `Reserved`, and `Cell` have all permissions, so a
+                        // `ChildAccessForbidden(Reserved | Unique)` can never exist.
+                        (_, Unique) | (_, ReservedFrz { conflicted: false }) | (_, Cell) =>
                             unreachable!("this permission cannot cause an error"),
                         // No transition has `Reserved { conflicted: false }` or `ReservedIM`
                         // as its `.to` unless it's a noop. `Cell` cannot be in its `.to`
@@ -527,11 +527,11 @@ pub mod diagnostics {
                         (ReservedFrz { conflicted: false } | ReservedIM | Cell, _) =>
                             unreachable!("self is a noop transition"),
                         // All transitions produced in normal executions (using `apply_access`)
-                        // change permissions in the order `Reserved -> Active -> Frozen -> Disabled`.
+                        // change permissions in the order `Reserved -> Unique -> Frozen -> Disabled`.
                         // We assume that the error was triggered on the same location that
                         // the transition `self` applies to, so permissions found must be increasing
                         // in the order `self.from < self.to <= insufficient.inner`
-                        (Active | Frozen | Disabled, ReservedFrz { .. } | ReservedIM)
+                        (Unique | Frozen | Disabled, ReservedFrz { .. } | ReservedIM)
                         | (Disabled, Frozen)
                         | (ReservedFrz { .. }, ReservedIM) =>
                             unreachable!("permissions between self and err must be increasing"),
@@ -540,29 +540,29 @@ pub mod diagnostics {
                 TransitionError::ProtectedDisabled(before_disabled) => {
                     // Show how we got to the starting point of the forbidden transition,
                     // but ignore what came before.
-                    // This eliminates transitions like `Reserved -> Active`
+                    // This eliminates transitions like `Reserved -> Unique`
                     // when the error is a `Frozen -> Disabled`.
                     match (self.to, before_disabled.inner) {
                         // We absolutely want to know where it was activated/frozen/marked
                         // conflicted.
-                        (Active, Active) => true,
+                        (Unique, Unique) => true,
                         (Frozen, Frozen) => true,
                         (
                             ReservedFrz { conflicted: true, .. },
                             ReservedFrz { conflicted: true, .. },
                         ) => true,
                         // If the error is a transition `Frozen -> Disabled`, then we don't really
-                        // care whether before that was `Reserved -> Active -> Frozen` or
+                        // care whether before that was `Reserved -> Unique -> Frozen` or
                         // `Frozen` directly.
                         // The error will only show either
                         // - created as Reserved { conflicted: false },
                         //   then Reserved { .. } -> Disabled is forbidden
                         // - created as Reserved { conflicted: false },
-                        //   then Active -> Disabled is forbidden
+                        //   then Unique -> Disabled is forbidden
                         // A potential `Reserved { conflicted: false }
                         //   -> Reserved { conflicted: true }` is inexistant or irrelevant,
-                        // and so is the `Reserved { conflicted: false } -> Active`
-                        (Active, Frozen) => false,
+                        // and so is the `Reserved { conflicted: false } -> Unique`
+                        (Unique, Frozen) => false,
                         (ReservedFrz { conflicted: true }, _) => false,
 
                         (_, Disabled) =>
@@ -575,12 +575,12 @@ pub mod diagnostics {
                         (ReservedFrz { conflicted: false } | ReservedIM | Cell, _) =>
                             unreachable!("self is a noop transition"),
 
-                        // Permissions only evolve in the order `Reserved -> Active -> Frozen -> Disabled`,
+                        // Permissions only evolve in the order `Reserved -> Unique -> Frozen -> Disabled`,
                         // so permissions found must be increasing in the order
                         // `self.from < self.to <= forbidden.from < forbidden.to`.
-                        (Disabled, Cell | ReservedFrz { .. } | ReservedIM | Active | Frozen)
-                        | (Frozen, Cell | ReservedFrz { .. } | ReservedIM | Active)
-                        | (Active, Cell | ReservedFrz { .. } | ReservedIM) =>
+                        (Disabled, Cell | ReservedFrz { .. } | ReservedIM | Unique | Frozen)
+                        | (Frozen, Cell | ReservedFrz { .. } | ReservedIM | Unique)
+                        | (Unique, Cell | ReservedFrz { .. } | ReservedIM) =>
                             unreachable!("permissions between self and err must be increasing"),
                     }
                 }
@@ -617,7 +617,7 @@ mod propagation_optimization_checks {
     impl Exhaustive for PermissionPriv {
         fn exhaustive() -> Box<dyn Iterator<Item = Self>> {
             Box::new(
-                vec![Active, Frozen, Disabled, ReservedIM, Cell]
+                vec![Unique, Frozen, Disabled, ReservedIM, Cell]
                     .into_iter()
                     .chain(<bool>::exhaustive().map(|conflicted| ReservedFrz { conflicted })),
             )
@@ -730,7 +730,7 @@ mod propagation_optimization_checks {
 
     #[test]
     // Check that all transitions are consistent with the order on PermissionPriv,
-    // i.e. Reserved -> Active -> Frozen -> Disabled
+    // i.e. Reserved -> Unique -> Frozen -> Disabled
     fn permissionpriv_partialord_is_reachability() {
         let reach = {
             let mut reach = rustc_data_structures::fx::FxHashSet::default();
diff --git a/src/tools/miri/src/borrow_tracker/tree_borrows/tree.rs b/src/tools/miri/src/borrow_tracker/tree_borrows/tree.rs
index 22bd63bd6b6..9e7d272ee4b 100644
--- a/src/tools/miri/src/borrow_tracker/tree_borrows/tree.rs
+++ b/src/tools/miri/src/borrow_tracker/tree_borrows/tree.rs
@@ -57,7 +57,7 @@ pub(super) struct LocationState {
 impl LocationState {
     /// Constructs a new initial state. It has neither been accessed, nor been subjected
     /// to any foreign access yet.
-    /// The permission is not allowed to be `Active`.
+    /// The permission is not allowed to be `Unique`.
     /// `sifa` is the (strongest) idempotent foreign access, see `foreign_access_skipping.rs`
     pub fn new_non_accessed(permission: Permission, sifa: IdempotentForeignAccess) -> Self {
         assert!(permission.is_initial() || permission.is_disabled());
@@ -80,7 +80,7 @@ impl LocationState {
     /// Check if the state can exist as the initial permission of a pointer.
     ///
     /// Do not confuse with `is_accessed`, the two are almost orthogonal
-    /// as apart from `Active` which is not initial and must be accessed,
+    /// as apart from `Unique` which is not initial and must be accessed,
     /// any other permission can have an arbitrary combination of being
     /// initial/accessed.
     /// FIXME: when the corresponding `assert` in `tree_borrows/mod.rs` finally
@@ -170,7 +170,7 @@ impl LocationState {
             }
             if self.permission.is_frozen() && access_kind == AccessKind::Read {
                 // A foreign read to a `Frozen` tag will have almost no observable effect.
-                // It's a theorem that `Frozen` nodes have no active children, so all children
+                // It's a theorem that `Frozen` nodes have no `Unique` children, so all children
                 // already survive foreign reads. Foreign reads in general have almost no
                 // effect, the only further thing they could do is make protected `Reserved`
                 // nodes become conflicted, i.e. make them reject child writes for the further
@@ -265,7 +265,7 @@ pub(super) struct Node {
     pub children: SmallVec<[UniIndex; 4]>,
     /// Either `Reserved`,  `Frozen`, or `Disabled`, it is the permission this tag will
     /// lazily be initialized to on the first access.
-    /// It is only ever `Disabled` for a tree root, since the root is initialized to `Active` by
+    /// It is only ever `Disabled` for a tree root, since the root is initialized to `Unique` by
     /// its own separate mechanism.
     default_initial_perm: Permission,
     /// The default initial (strongest) idempotent foreign access.
@@ -598,14 +598,14 @@ impl Tree {
         };
         let rperms = {
             let mut perms = UniValMap::default();
-            // We manually set it to `Active` on all in-bounds positions.
-            // We also ensure that it is accessed, so that no `Active` but
+            // We manually set it to `Unique` on all in-bounds positions.
+            // We also ensure that it is accessed, so that no `Unique` but
             // not yet accessed nodes exist. Essentially, we pretend there
-            // was a write that initialized these to `Active`.
+            // was a write that initialized these to `Unique`.
             perms.insert(
                 root_idx,
                 LocationState::new_accessed(
-                    Permission::new_active(),
+                    Permission::new_unique(),
                     IdempotentForeignAccess::None,
                 ),
             );
@@ -790,7 +790,7 @@ impl<'tcx> Tree {
     /// - the access will be applied only to accessed locations of the allocation,
     /// - it will not be visible to children,
     /// - it will be recorded as a `FnExit` diagnostic access
-    /// - and it will be a read except if the location is `Active`, i.e. has been written to,
+    /// - and it will be a read except if the location is `Unique`, i.e. has been written to,
     ///   in which case it will be a write.
     ///
     /// `LocationState::perform_access` will take care of raising transition
diff --git a/src/tools/miri/src/borrow_tracker/tree_borrows/tree/tests.rs b/src/tools/miri/src/borrow_tracker/tree_borrows/tree/tests.rs
index d9b3696e4f8..83232615616 100644
--- a/src/tools/miri/src/borrow_tracker/tree_borrows/tree/tests.rs
+++ b/src/tools/miri/src/borrow_tracker/tree_borrows/tree/tests.rs
@@ -420,7 +420,7 @@ mod spurious_read {
     /// `(LocStateProt, LocStateProt)` where the two states are not guaranteed
     /// to be updated at the same time.
     /// Some `LocStateProtPair` may be unreachable through normal means
-    /// such as `x: Active, y: Active` in the case of mutually foreign pointers.
+    /// such as `x: Unique, y: Unique` in the case of mutually foreign pointers.
     struct LocStateProtPair {
         xy_rel: RelPosXY,
         x: LocStateProt,
@@ -709,7 +709,7 @@ mod spurious_read {
         let mut err = 0;
         for pat in Pattern::exhaustive() {
             let Ok(initial_source) = pat.initial_state() else {
-                // Failed to retag `x` in the source (e.g. `y` was protected Active)
+                // Failed to retag `x` in the source (e.g. `y` was protected Unique)
                 continue;
             };
             // `x` must stay protected, but the function protecting `y` might return here
diff --git a/src/tools/miri/tests/fail/async-shared-mutable.tree.stderr b/src/tools/miri/tests/fail/async-shared-mutable.tree.stderr
index 449a29088a0..dc8b4f6665a 100644
--- a/src/tools/miri/tests/fail/async-shared-mutable.tree.stderr
+++ b/src/tools/miri/tests/fail/async-shared-mutable.tree.stderr
@@ -16,7 +16,7 @@ LL | |             Poll::<()>::Pending
 LL | |         })
 LL | |         .await
    | |______________^
-help: the accessed tag <TAG> later transitioned to Active due to a child write access at offsets [OFFSET]
+help: the accessed tag <TAG> later transitioned to Unique due to a child write access at offsets [OFFSET]
   --> tests/fail/async-shared-mutable.rs:LL:CC
    |
 LL |             *x = 1;
diff --git a/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.tree.stderr b/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.tree.stderr
index 3c8ec7f7d3e..6a1f7761a41 100644
--- a/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/box_noalias_violation.tree.stderr
@@ -7,7 +7,7 @@ LL |     *y
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/tree-borrows.md for further information
    = help: the accessed tag <TAG> is foreign to the protected tag <TAG> (i.e., it is not a child)
-   = help: this foreign read access would cause the protected tag <TAG> (currently Active) to become Disabled
+   = help: this foreign read access would cause the protected tag <TAG> (currently Unique) to become Disabled
    = help: protected tags must never be Disabled
 help: the accessed tag <TAG> was created here
   --> tests/fail/both_borrows/box_noalias_violation.rs:LL:CC
@@ -19,7 +19,7 @@ help: the protected tag <TAG> was created here, in the initial state Reserved
    |
 LL | unsafe fn test(mut x: Box<i32>, y: *const i32) -> i32 {
    |                ^^^^^
-help: the protected tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the protected tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/both_borrows/box_noalias_violation.rs:LL:CC
    |
 LL |     *x = 5;
diff --git a/src/tools/miri/tests/fail/both_borrows/illegal_write6.tree.stderr b/src/tools/miri/tests/fail/both_borrows/illegal_write6.tree.stderr
index 6780e52c3ba..1547a6ca73a 100644
--- a/src/tools/miri/tests/fail/both_borrows/illegal_write6.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/illegal_write6.tree.stderr
@@ -7,7 +7,7 @@ LL |     unsafe { *y = 2 };
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/tree-borrows.md for further information
    = help: the accessed tag <TAG> is foreign to the protected tag <TAG> (i.e., it is not a child)
-   = help: this foreign write access would cause the protected tag <TAG> (currently Active) to become Disabled
+   = help: this foreign write access would cause the protected tag <TAG> (currently Unique) to become Disabled
    = help: protected tags must never be Disabled
 help: the accessed tag <TAG> was created here
   --> tests/fail/both_borrows/illegal_write6.rs:LL:CC
@@ -19,7 +19,7 @@ help: the protected tag <TAG> was created here, in the initial state Reserved
    |
 LL | fn foo(a: &mut u32, y: *mut u32) -> u32 {
    |        ^
-help: the protected tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the protected tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/both_borrows/illegal_write6.rs:LL:CC
    |
 LL |     *a = 1;
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_locals_alias.tree.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_locals_alias.tree.stderr
index 2266a9c39f9..2d9ce2aa1fb 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_locals_alias.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_locals_alias.tree.stderr
@@ -7,7 +7,7 @@ LL |             Call(_unit = callee(Move(non_copy), Move(non_copy)), ReturnTo(a
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/tree-borrows.md for further information
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
-   = help: this foreign read access would cause the protected tag <TAG> (currently Active) to become Disabled
+   = help: this foreign read access would cause the protected tag <TAG> (currently Unique) to become Disabled
    = help: protected tags must never be Disabled
 help: the accessed tag <TAG> was created here
   --> tests/fail/function_calls/arg_inplace_locals_alias.rs:LL:CC
@@ -19,7 +19,7 @@ help: the protected tag <TAG> was created here, in the initial state Reserved
    |
 LL |     y.0 = 0;
    |     ^^^^^^^
-help: the protected tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the protected tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/function_calls/arg_inplace_locals_alias.rs:LL:CC
    |
 LL |     y.0 = 0;
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_locals_alias_ret.tree.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_locals_alias_ret.tree.stderr
index b7f514de0af..42e391b5daf 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_locals_alias_ret.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_locals_alias_ret.tree.stderr
@@ -7,7 +7,7 @@ LL |             Call(_non_copy = callee(Move(_non_copy)), ReturnTo(after_call),
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/tree-borrows.md for further information
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
-   = help: this reborrow (acting as a foreign read access) would cause the protected tag <TAG> (currently Active) to become Disabled
+   = help: this reborrow (acting as a foreign read access) would cause the protected tag <TAG> (currently Unique) to become Disabled
    = help: protected tags must never be Disabled
 help: the accessed tag <TAG> was created here
   --> tests/fail/function_calls/arg_inplace_locals_alias_ret.rs:LL:CC
@@ -19,7 +19,7 @@ help: the protected tag <TAG> was created here, in the initial state Reserved
    |
 LL |     x
    |     ^
-help: the protected tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the protected tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/function_calls/arg_inplace_locals_alias_ret.rs:LL:CC
    |
 LL |     x
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.tree.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.tree.stderr
index 1995528e9f9..74706d6b9f6 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_mutate.tree.stderr
@@ -7,7 +7,7 @@ LL |     unsafe { ptr.write(S(0)) };
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/tree-borrows.md for further information
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
-   = help: this foreign write access would cause the protected tag <TAG> (currently Active) to become Disabled
+   = help: this foreign write access would cause the protected tag <TAG> (currently Unique) to become Disabled
    = help: protected tags must never be Disabled
 help: the accessed tag <TAG> was created here
   --> tests/fail/function_calls/arg_inplace_mutate.rs:LL:CC
@@ -24,7 +24,7 @@ help: the protected tag <TAG> was created here, in the initial state Reserved
    |
 LL |     unsafe { ptr.write(S(0)) };
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
-help: the protected tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the protected tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/function_calls/arg_inplace_mutate.rs:LL:CC
    |
 LL |     unsafe { ptr.write(S(0)) };
diff --git a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.tree.stderr b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.tree.stderr
index e506a61c6bb..c8c0e5c37ef 100644
--- a/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/arg_inplace_observe_during.tree.stderr
@@ -7,7 +7,7 @@ LL |     unsafe { ptr.read() };
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/tree-borrows.md for further information
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
-   = help: this foreign read access would cause the protected tag <TAG> (currently Active) to become Disabled
+   = help: this foreign read access would cause the protected tag <TAG> (currently Unique) to become Disabled
    = help: protected tags must never be Disabled
 help: the accessed tag <TAG> was created here
   --> tests/fail/function_calls/arg_inplace_observe_during.rs:LL:CC
@@ -24,7 +24,7 @@ help: the protected tag <TAG> was created here, in the initial state Reserved
    |
 LL |     x.0 = 0;
    |     ^^^^^^^
-help: the protected tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the protected tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/function_calls/arg_inplace_observe_during.rs:LL:CC
    |
 LL |     x.0 = 0;
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.tree.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.tree.stderr
index b1aa2ba2886..b43e19c3905 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_read.tree.stderr
@@ -7,7 +7,7 @@ LL |     unsafe { ptr.read() };
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/tree-borrows.md for further information
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
-   = help: this foreign read access would cause the protected tag <TAG> (currently Active) to become Disabled
+   = help: this foreign read access would cause the protected tag <TAG> (currently Unique) to become Disabled
    = help: protected tags must never be Disabled
 help: the accessed tag <TAG> was created here
   --> tests/fail/function_calls/return_pointer_aliasing_read.rs:LL:CC
@@ -24,7 +24,7 @@ help: the protected tag <TAG> was created here, in the initial state Reserved
    |
 LL |     unsafe { ptr.read() };
    |     ^^^^^^^^^^^^^^^^^^^^^
-help: the protected tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the protected tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/function_calls/return_pointer_aliasing_read.rs:LL:CC
    |
 LL |     unsafe { ptr.read() };
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.tree.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.tree.stderr
index 0cf449ea3ec..deefb24b785 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write.tree.stderr
@@ -7,7 +7,7 @@ LL |     unsafe { ptr.write(0) };
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/tree-borrows.md for further information
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
-   = help: this foreign write access would cause the protected tag <TAG> (currently Active) to become Disabled
+   = help: this foreign write access would cause the protected tag <TAG> (currently Unique) to become Disabled
    = help: protected tags must never be Disabled
 help: the accessed tag <TAG> was created here
   --> tests/fail/function_calls/return_pointer_aliasing_write.rs:LL:CC
@@ -24,7 +24,7 @@ help: the protected tag <TAG> was created here, in the initial state Reserved
    |
 LL |     unsafe { ptr.write(0) };
    |     ^^^^^^^^^^^^^^^^^^^^^^^
-help: the protected tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the protected tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/function_calls/return_pointer_aliasing_write.rs:LL:CC
    |
 LL |     unsafe { ptr.write(0) };
diff --git a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.tree.stderr b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.tree.stderr
index a006c6feae4..76ccf39744d 100644
--- a/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.tree.stderr
+++ b/src/tools/miri/tests/fail/function_calls/return_pointer_aliasing_write_tail_call.tree.stderr
@@ -7,7 +7,7 @@ LL |     unsafe { ptr.write(0) };
    = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/tree-borrows.md for further information
    = help: the accessed tag <TAG> (root of the allocation) is foreign to the protected tag <TAG> (i.e., it is not a child)
-   = help: this foreign write access would cause the protected tag <TAG> (currently Active) to become Disabled
+   = help: this foreign write access would cause the protected tag <TAG> (currently Unique) to become Disabled
    = help: protected tags must never be Disabled
 help: the accessed tag <TAG> was created here
   --> tests/fail/function_calls/return_pointer_aliasing_write_tail_call.rs:LL:CC
@@ -24,7 +24,7 @@ help: the protected tag <TAG> was created here, in the initial state Reserved
    |
 LL |     unsafe { ptr.write(0) };
    |     ^^^^^^^^^^^^^^^^^^^^^^^
-help: the protected tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the protected tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/function_calls/return_pointer_aliasing_write_tail_call.rs:LL:CC
    |
 LL |     unsafe { ptr.write(0) };
diff --git a/src/tools/miri/tests/fail/tree_borrows/alternate-read-write.stderr b/src/tools/miri/tests/fail/tree_borrows/alternate-read-write.stderr
index 9e955a6d5b1..aff482abfa0 100644
--- a/src/tools/miri/tests/fail/tree_borrows/alternate-read-write.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/alternate-read-write.stderr
@@ -12,7 +12,7 @@ help: the accessed tag <TAG> was created here, in the initial state Reserved
    |
 LL |     let y = unsafe { &mut *(x as *mut u8) };
    |                      ^^^^^^^^^^^^^^^^^^^^
-help: the accessed tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x1]
+help: the accessed tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x1]
   --> tests/fail/tree_borrows/alternate-read-write.rs:LL:CC
    |
 LL |     *y += 1; // Success
diff --git a/src/tools/miri/tests/fail/tree_borrows/fnentry_invalidation.stderr b/src/tools/miri/tests/fail/tree_borrows/fnentry_invalidation.stderr
index 7886029dccf..bfd6854514e 100644
--- a/src/tools/miri/tests/fail/tree_borrows/fnentry_invalidation.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/fnentry_invalidation.stderr
@@ -12,7 +12,7 @@ help: the accessed tag <TAG> was created here, in the initial state Reserved
    |
 LL |     let z = &mut x as *mut i32;
    |             ^^^^^^
-help: the accessed tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the accessed tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/tree_borrows/fnentry_invalidation.rs:LL:CC
    |
 LL |         *z = 1;
diff --git a/src/tools/miri/tests/fail/tree_borrows/parent_read_freezes_raw_mut.stderr b/src/tools/miri/tests/fail/tree_borrows/parent_read_freezes_raw_mut.stderr
index 2edbbd80569..7a713abcbc4 100644
--- a/src/tools/miri/tests/fail/tree_borrows/parent_read_freezes_raw_mut.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/parent_read_freezes_raw_mut.stderr
@@ -12,7 +12,7 @@ help: the accessed tag <TAG> was created here, in the initial state Reserved
    |
 LL |         let mref = &mut root;
    |                    ^^^^^^^^^
-help: the accessed tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x1]
+help: the accessed tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x1]
   --> tests/fail/tree_borrows/parent_read_freezes_raw_mut.rs:LL:CC
    |
 LL |         *ptr = 0; // Write
diff --git a/src/tools/miri/tests/fail/tree_borrows/pass_invalid_mut.stderr b/src/tools/miri/tests/fail/tree_borrows/pass_invalid_mut.stderr
index c00c67173b7..9a70d248aa0 100644
--- a/src/tools/miri/tests/fail/tree_borrows/pass_invalid_mut.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/pass_invalid_mut.stderr
@@ -18,7 +18,7 @@ help: the conflicting tag <TAG> was created here, in the initial state Reserved
    |
 LL |     let xref = unsafe { &mut *xraw };
    |                         ^^^^^^^^^^
-help: the conflicting tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x4]
+help: the conflicting tag <TAG> later transitioned to Unique due to a child write access at offsets [0x0..0x4]
   --> tests/fail/tree_borrows/pass_invalid_mut.rs:LL:CC
    |
 LL |     *xref = 18; // activate xref
diff --git a/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.rs b/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.rs
index 024a14600b1..3e5d83911ee 100644
--- a/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.rs
+++ b/src/tools/miri/tests/fail/tree_borrows/reservedim_spurious_write.rs
@@ -60,8 +60,7 @@ fn main() {
         fn inner(x: &mut u8, b: IdxBarrier) {
             *x = 42; // activate immediately
             synchronized!(b, "[lazy] retag y (&mut, protect, IM)");
-            // A spurious write should be valid here because `x` is
-            // `Active` and protected.
+            // A spurious write should be valid here because `x` is `Unique` and protected.
             if cfg!(with) {
                 synchronized!(b, "spurious write x (executed)");
                 *x = 64;
diff --git a/src/tools/miri/tests/fail/tree_borrows/return_invalid_mut.stderr b/src/tools/miri/tests/fail/tree_borrows/return_invalid_mut.stderr
index ba8ab472872..4b6308847bb 100644
--- a/src/tools/miri/tests/fail/tree_borrows/return_invalid_mut.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/return_invalid_mut.stderr
@@ -18,7 +18,7 @@ help: the conflicting tag <TAG> was created here, in the initial state Reserved
    |
 LL |     let ret = unsafe { &mut (*xraw).1 };
    |                        ^^^^^^^^^^^^^^
-help: the conflicting tag <TAG> later transitioned to Active due to a child write access at offsets [0x4..0x8]
+help: the conflicting tag <TAG> later transitioned to Unique due to a child write access at offsets [0x4..0x8]
   --> tests/fail/tree_borrows/return_invalid_mut.rs:LL:CC
    |
 LL |     *ret = *ret; // activate
diff --git a/src/tools/miri/tests/fail/tree_borrows/subtree_traversal_skipping_diagnostics.rs b/src/tools/miri/tests/fail/tree_borrows/subtree_traversal_skipping_diagnostics.rs
index 6514334b09d..94a3bb80544 100644
--- a/src/tools/miri/tests/fail/tree_borrows/subtree_traversal_skipping_diagnostics.rs
+++ b/src/tools/miri/tests/fail/tree_borrows/subtree_traversal_skipping_diagnostics.rs
@@ -5,7 +5,7 @@
 
 // When this method is called, the tree will be a single line and look like this,
 // with other_ptr being the root at the top
-// other_ptr = root : Active
+// other_ptr = root : Unique
 // intermediary     : Frozen // an intermediary node
 // m                : Reserved
 fn write_to_mut(m: &mut u8, other_ptr: *const u8) {
diff --git a/src/tools/miri/tests/fail/tree_borrows/unique.default.stderr b/src/tools/miri/tests/fail/tree_borrows/unique.default.stderr
deleted file mode 100644
index c7d72f70f40..00000000000
--- a/src/tools/miri/tests/fail/tree_borrows/unique.default.stderr
+++ /dev/null
@@ -1,32 +0,0 @@
-error: Undefined Behavior: write access through <TAG> at ALLOC[0x0] is forbidden
-  --> tests/fail/tree_borrows/unique.rs:LL:CC
-   |
-LL |         *uniq.as_ptr() = 3;
-   |         ^^^^^^^^^^^^^^^^^^ write access through <TAG> at ALLOC[0x0] is forbidden
-   |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Tree Borrows rules it violated are still experimental
-   = help: the accessed tag <TAG> has state Frozen which forbids this child write access
-help: the accessed tag <TAG> was created here, in the initial state Reserved
-  --> tests/fail/tree_borrows/unique.rs:LL:CC
-   |
-LL |     let refmut = &mut data;
-   |                  ^^^^^^^^^
-help: the accessed tag <TAG> later transitioned to Active due to a child write access at offsets [0x0..0x1]
-  --> tests/fail/tree_borrows/unique.rs:LL:CC
-   |
-LL |         *uniq.as_ptr() = 1; // activation
-   |         ^^^^^^^^^^^^^^^^^^
-   = help: this transition corresponds to the first write to a 2-phase borrowed mutable reference
-help: the accessed tag <TAG> later transitioned to Frozen due to a foreign read access at offsets [0x0..0x1]
-  --> tests/fail/tree_borrows/unique.rs:LL:CC
-   |
-LL |         let _definitely_parent = data; // definitely Frozen by now
-   |                                  ^^^^
-   = help: this transition corresponds to a loss of write permissions
-   = note: BACKTRACE (of the first span):
-   = note: inside `main` at tests/fail/tree_borrows/unique.rs:LL:CC
-
-note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
-
-error: aborting due to 1 previous error
-
diff --git a/src/tools/miri/tests/pass/tree_borrows/cell-inside-box.rs b/src/tools/miri/tests/pass/tree_borrows/cell-inside-box.rs
index adf2f4e845b..4a868455c84 100644
--- a/src/tools/miri/tests/pass/tree_borrows/cell-inside-box.rs
+++ b/src/tools/miri/tests/pass/tree_borrows/cell-inside-box.rs
@@ -20,7 +20,7 @@ pub fn main() {
         name!(ptr2);
 
         // We perform a write through `x`.
-        // Because `ptr1` is ReservedIM, a child write will make it transition to Active.
+        // Because `ptr1` is ReservedIM, a child write will make it transition to Unique.
         // Because `ptr2` is ReservedIM, a foreign write doesn't have any effect on it.
         let x = (*ptr1).get();
         *x = 1;
diff --git a/src/tools/miri/tests/pass/tree_borrows/reborrow-is-read.rs b/src/tools/miri/tests/pass/tree_borrows/reborrow-is-read.rs
index 4fbccef2367..edd649b91ed 100644
--- a/src/tools/miri/tests/pass/tree_borrows/reborrow-is-read.rs
+++ b/src/tools/miri/tests/pass/tree_borrows/reborrow-is-read.rs
@@ -6,7 +6,7 @@
 mod utils;
 
 // To check that a reborrow is counted as a Read access, we use a reborrow
-// with no additional Read to Freeze an Active pointer.
+// with no additional Read to Freeze an Unique pointer.
 
 fn main() {
     unsafe {
@@ -15,7 +15,7 @@ fn main() {
         let alloc_id = alloc_id!(parent);
         let x = &mut *parent;
         name!(x);
-        *x = 0; // x is now Active
+        *x = 0; // x is now Unique
         print_state!(alloc_id);
         let y = &mut *parent;
         name!(y);
diff --git a/src/tools/miri/tests/pass/tree_borrows/reserved.rs b/src/tools/miri/tests/pass/tree_borrows/reserved.rs
index c57cd7fcf0a..83e1d9c70ed 100644
--- a/src/tools/miri/tests/pass/tree_borrows/reserved.rs
+++ b/src/tools/miri/tests/pass/tree_borrows/reserved.rs
@@ -68,7 +68,7 @@ unsafe fn cell_unprotected_read() {
 }
 
 // Foreign Write on an interior mutable pointer is a noop.
-// Also y must become Active.
+// Also y must become Unique.
 unsafe fn cell_unprotected_write() {
     print("[interior mut] Foreign Write: Re* -> Re*");
     let base = &mut UnsafeCell::new(0u64);
@@ -97,7 +97,7 @@ unsafe fn int_protected_read() {
 }
 
 // Foreign Read on a Reserved is a noop.
-// Also y must become Active.
+// Also y must become Unique.
 unsafe fn int_unprotected_read() {
     print("[] Foreign Read: Res -> Res");
     let base = &mut 0u8;