remove BorrowTrackerMethod::Off

Author: Vanille-N

src/borrow_tracker/mod.rs

@@ -80,6 +80,8 @@ impl VisitTags for FrameExtra {
 /// Extra global state, available to the memory access hooks.
 #[derive(Debug)]
 pub struct GlobalStateInner {
+    /// Borrow tracker method currently in use (except BorrowTrackerMethod::Off)
+    pub borrow_tracker_method: BorrowTrackerMethod,
     /// Next unused pointer ID (tag).
     pub next_ptr_tag: BorTag,
     /// Table storing the "base" tag for each allocation.
@@ -163,11 +165,13 @@ pub enum ProtectorKind {
 /// Utilities for initialization and ID generation
 impl GlobalStateInner {
     pub fn new(
+        borrow_tracker_method: BorrowTrackerMethod,
         tracked_pointer_tags: FxHashSet<BorTag>,
         tracked_call_ids: FxHashSet<CallId>,
         retag_fields: RetagFields,
     ) -> Self {
         GlobalStateInner {
+            borrow_tracker_method,
             next_ptr_tag: BorTag::one(),
             base_ptr_tags: FxHashMap::default(),
             next_call_id: NonZeroU64::new(1).unwrap(),
@@ -225,21 +229,20 @@ impl GlobalStateInner {
 
 /// Which borrow tracking method to use
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
-pub enum Method {
+pub enum BorrowTrackerMethod {
     /// Stacked Borrows, as implemented in borrow_tracker/stacked
     StackedBorrows,
-    /// Do not track borrows
-    Off,
 }
 
-impl Method {
+impl BorrowTrackerMethod {
     pub fn is_active(self) -> bool {
         !matches!(self, Method::Off)
     }
 
     pub fn instanciate_global_state(self, config: &MiriConfig) -> Option<GlobalState> {
         self.is_active().then(|| {
             RefCell::new(GlobalStateInner::new(
+                self,
                 config.tracked_pointer_tags.clone(),
                 config.tracked_call_ids.clone(),
                 config.retag_fields,
@@ -256,15 +259,15 @@ impl Method {
         machine: &MiriMachine<'_, '_>,
     ) -> AllocExtra {
         match self {
-            Method::StackedBorrows =>
+            BorrowTrackerMethod::StackedBorrows =>
                 AllocExtra::StackedBorrows(Box::new(RefCell::new(Stacks::new_allocation(
                     id,
                     alloc.size(),
                     global.unwrap(),
                     kind,
                     machine,
                 )))),
-            Method::Off => AllocExtra::None,
+            BorrowTrackerMethod::Off => AllocExtra::None,
         }
     }
 
@@ -305,8 +308,6 @@ impl Method {
 pub enum AllocExtra {
     /// Data corresponding to Stacked Borrows
     StackedBorrows(Box<RefCell<stacked_borrows::AllocExtra>>),
-    /// No data because borrow tracking is deactivated
-    None,
 }
 
 impl AllocExtra {