pthread_rwlock: also store ID outside addressable memory

Author: RalfJung

src/tools/miri/src/concurrency/sync.rs

@@ -79,9 +79,6 @@ struct Mutex {
 queue:VecDeque<ThreadId>,
 /// Mutex clock. This tracks the moment of the last unlock.
 clock:VClock,
-
-/// Additional data that can be set by shim implementations.
-data:Option<Box<dynAny>>,
 }
 
 declare_id!(RwLockId);
@@ -118,9 +115,6 @@ struct RwLock {
 /// locks.
 /// This is only relevant when there is an active reader.
 clock_current_readers:VClock,
-
-/// Additional data that can be set by shim implementations.
-data:Option<Box<dynAny>>,
 }
 
 declare_id!(CondvarId);
@@ -290,56 +284,22 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
 &mutself,
 lock:&MPlaceTy<'tcx>,
 offset:u64,
-initialize_data:implfor<'a>FnOnce(
-&'amutMiriInterpCx<'tcx>,
-) -> InterpResult<'tcx,Option<Box<dynAny>>>,
 ) -> InterpResult<'tcx,MutexId>{
 let this = self.eval_context_mut();
  this.get_or_create_id(
  lock,
  offset,
  |ecx| &mut ecx.machine.sync.mutexes,
- |ecx| initialize_data(ecx).map(|data| Mutex{ data, ..Default::default()}),
+ |_ecx| interp_ok(Mutex::default()),
 )?
 .ok_or_else(|| err_ub_format!("mutex has invalid ID"))
 .into()
 }
 
-/// Retrieve the additional data stored for a mutex.
-fnmutex_get_data<'a,T:'static>(&'amutself,id:MutexId) -> Option<&'aT>
-where
-'tcx:'a,
-{
-let this = self.eval_context_ref();
- this.machine.sync.mutexes[id].data.as_deref().and_then(|p| p.downcast_ref::<T>())
-}
-
-fnrwlock_get_or_create_id(
-&mutself,
-lock:&MPlaceTy<'tcx>,
-offset:u64,
-initialize_data:implfor<'a>FnOnce(
-&'amutMiriInterpCx<'tcx>,
-) -> InterpResult<'tcx,Option<Box<dynAny>>>,
-) -> InterpResult<'tcx,RwLockId>{
+/// Eagerly create and initialize a new rwlock.
+fnrwlock_create(&mutself) -> RwLockId{
 let this = self.eval_context_mut();
- this.get_or_create_id(
- lock,
- offset,
- |ecx| &mut ecx.machine.sync.rwlocks,
- |ecx| initialize_data(ecx).map(|data| RwLock{ data, ..Default::default()}),
-)?
-.ok_or_else(|| err_ub_format!("rwlock has invalid ID"))
-.into()
-}
-
-/// Retrieve the additional data stored for a rwlock.
-fnrwlock_get_data<'a,T:'static>(&'amutself,id:RwLockId) -> Option<&'aT>
-where
-'tcx:'a,
-{
-let this = self.eval_context_ref();
- this.machine.sync.rwlocks[id].data.as_deref().and_then(|p| p.downcast_ref::<T>())
+ this.machine.sync.rwlocks.push(Default::default())
 }
 
 /// Eagerly create and initialize a new condvar.

src/tools/miri/src/shims/unix/macos/sync.rs

@@ -20,7 +20,7 @@ trait EvalContextExtPriv<'tcx>: crate::MiriInterpCxExt<'tcx> {
 // os_unfair_lock holds a 32-bit value, is initialized with zero and
 // must be assumed to be opaque. Therefore, we can just store our
 // internal mutex ID in the structure without anyone noticing.
- this.mutex_get_or_create_id(&lock,0, |_| interp_ok(None))
+ this.mutex_get_or_create_id(&lock,/* offset */0)
 }
 }