Auto merge of #115388 - Zoxc:sharded-lock, r=SparrowLii

Add optimized lock methods for `Sharded` and refactor `Lock`

This adds methods to `Sharded` which pick a shard and also locks it. These branch on parallelism just once instead of twice, improving performance.

Benchmark for `cfg(parallel_compiler)` and 1 thread:
<table><tr><td rowspan="2">Benchmark</td><td colspan="1"><b>Before</b></th><td colspan="2"><b>After</b></th></tr><tr><td align="right">Time</td><td align="right">Time</td><td align="right">%</th></tr><tr><td>🟣 <b>clap</b>:check</td><td align="right">1.6461s</td><td align="right">1.6345s</td><td align="right"> -0.70%</td></tr><tr><td>🟣 <b>hyper</b>:check</td><td align="right">0.2414s</td><td align="right">0.2394s</td><td align="right"> -0.83%</td></tr><tr><td>🟣 <b>regex</b>:check</td><td align="right">0.9205s</td><td align="right">0.9143s</td><td align="right"> -0.67%</td></tr><tr><td>🟣 <b>syn</b>:check</td><td align="right">1.4981s</td><td align="right">1.4869s</td><td align="right"> -0.75%</td></tr><tr><td>🟣 <b>syntex_syntax</b>:check</td><td align="right">5.7629s</td><td align="right">5.7256s</td><td align="right"> -0.65%</td></tr><tr><td>Total</td><td align="right">10.0690s</td><td align="right">10.0008s</td><td align="right"> -0.68%</td></tr><tr><td>Summary</td><td align="right">1.0000s</td><td align="right">0.9928s</td><td align="right"> -0.72%</td></tr></table>

cc `@SparrowLii`

compiler/rustc_data_structures/src/sharded.rs

@@ -1,7 +1,7 @@
 use crate::fx::{FxHashMap, FxHasher};
 #[cfg(parallel_compiler)]
 use crate::sync::{is_dyn_thread_safe, CacheAligned};
-use crate::sync::{Lock, LockGuard};
+use crate::sync::{Lock, LockGuard, Mode};
 #[cfg(parallel_compiler)]
 use itertools::Either;
 use std::borrow::Borrow;
@@ -73,6 +73,56 @@ impl<T> Sharded<T> {
         }
     }
 
+    /// The shard is selected by hashing `val` with `FxHasher`.
+    #[inline]
+    #[track_caller]
+    pub fn lock_shard_by_value<K: Hash + ?Sized>(&self, _val: &K) -> LockGuard<'_, T> {
+        match self {
+            Self::Single(single) => {
+                // Syncronization is disabled so use the `lock_assume_no_sync` method optimized
+                // for that case.
+
+                // SAFETY: We know `is_dyn_thread_safe` was false when creating the lock thus
+                // `might_be_dyn_thread_safe` was also false.
+                unsafe { single.lock_assume(Mode::NoSync) }
+            }
+            #[cfg(parallel_compiler)]
+            Self::Shards(..) => self.lock_shard_by_hash(make_hash(_val)),
+        }
+    }
+
+    #[inline]
+    #[track_caller]
+    pub fn lock_shard_by_hash(&self, hash: u64) -> LockGuard<'_, T> {
+        self.lock_shard_by_index(get_shard_hash(hash))
+    }
+
+    #[inline]
+    #[track_caller]
+    pub fn lock_shard_by_index(&self, _i: usize) -> LockGuard<'_, T> {
+        match self {
+            Self::Single(single) => {
+                // Syncronization is disabled so use the `lock_assume_no_sync` method optimized
+                // for that case.
+
+                // SAFETY: We know `is_dyn_thread_safe` was false when creating the lock thus
+                // `might_be_dyn_thread_safe` was also false.
+                unsafe { single.lock_assume(Mode::NoSync) }
+            }
+            #[cfg(parallel_compiler)]
+            Self::Shards(shards) => {
+                // Syncronization is enabled so use the `lock_assume_sync` method optimized
+                // for that case.
+
+                // SAFETY (get_unchecked): The index gets ANDed with the shard mask, ensuring it is
+                // always inbounds.
+                // SAFETY (lock_assume_sync): We know `is_dyn_thread_safe` was true when creating
+                // the lock thus `might_be_dyn_thread_safe` was also true.
+                unsafe { shards.get_unchecked(_i & (SHARDS - 1)).0.lock_assume(Mode::Sync) }
+            }
+        }
+    }
+
     #[inline]
     pub fn lock_shards(&self) -> impl Iterator<Item = LockGuard<'_, T>> {
         match self {
@@ -124,7 +174,7 @@ impl<K: Eq + Hash + Copy> ShardedHashMap<K, ()> {
         Q: Hash + Eq,
     {
         let hash = make_hash(value);
-        let mut shard = self.get_shard_by_hash(hash).lock();
+        let mut shard = self.lock_shard_by_hash(hash);
         let entry = shard.raw_entry_mut().from_key_hashed_nocheck(hash, value);
 
         match entry {
@@ -144,7 +194,7 @@ impl<K: Eq + Hash + Copy> ShardedHashMap<K, ()> {
         Q: Hash + Eq,
     {
         let hash = make_hash(&value);
-        let mut shard = self.get_shard_by_hash(hash).lock();
+        let mut shard = self.lock_shard_by_hash(hash);
         let entry = shard.raw_entry_mut().from_key_hashed_nocheck(hash, &value);
 
         match entry {
@@ -166,7 +216,7 @@ pub trait IntoPointer {
 impl<K: Eq + Hash + Copy + IntoPointer> ShardedHashMap<K, ()> {
     pub fn contains_pointer_to<T: Hash + IntoPointer>(&self, value: &T) -> bool {
         let hash = make_hash(&value);
-        let shard = self.get_shard_by_hash(hash).lock();
+        let shard = self.lock_shard_by_hash(hash);
         let value = value.into_pointer();
         shard.raw_entry().from_hash(hash, |entry| entry.into_pointer() == value).is_some()
     }

compiler/rustc_data_structures/src/sync.rs

@@ -49,7 +49,7 @@ use std::ops::{Deref, DerefMut};
 use std::panic::{catch_unwind, resume_unwind, AssertUnwindSafe};
 
 mod lock;
-pub use lock::{Lock, LockGuard};
+pub use lock::{Lock, LockGuard, Mode};
 
 mod worker_local;
 pub use worker_local::{Registry, WorkerLocal};
@@ -86,7 +86,6 @@ mod mode {
 
     // Whether thread safety might be enabled.
     #[inline]
-    #[cfg(parallel_compiler)]
     pub fn might_be_dyn_thread_safe() -> bool {
         DYN_THREAD_SAFE_MODE.load(Ordering::Relaxed) != DYN_NOT_THREAD_SAFE
     }

compiler/rustc_data_structures/src/sync/lock.rs

@@ -3,224 +3,229 @@
 //!
 //! When `cfg(parallel_compiler)` is not set, the lock is instead a wrapper around `RefCell`.
 
+#![allow(dead_code)]
+
+use std::fmt;
+
+#[cfg(parallel_compiler)]
+pub use maybe_sync::*;
 #[cfg(not(parallel_compiler))]
-use std::cell::RefCell;
-#[cfg(parallel_compiler)]
-use {
-    crate::cold_path,
-    crate::sync::DynSend,
-    crate::sync::DynSync,
-    parking_lot::lock_api::RawMutex,
-    std::cell::Cell,
-    std::cell::UnsafeCell,
-    std::fmt,
-    std::intrinsics::{likely, unlikely},
-    std::marker::PhantomData,
-    std::mem::ManuallyDrop,
-    std::ops::{Deref, DerefMut},
-};
+pub use no_sync::*;
 
-#[cfg(not(parallel_compiler))]
-pub use std::cell::RefMut as LockGuard;
-
-#[cfg(not(parallel_compiler))]
-#[derive(Debug)]
-pub struct Lock<T>(RefCell<T>);
-
-#[cfg(not(parallel_compiler))]
-impl<T> Lock<T> {
-    #[inline(always)]
-    pub fn new(inner: T) -> Self {
-        Lock(RefCell::new(inner))
-    }
-
-    #[inline(always)]
-    pub fn into_inner(self) -> T {
-        self.0.into_inner()
-    }
-
-    #[inline(always)]
-    pub fn get_mut(&mut self) -> &mut T {
-        self.0.get_mut()
-    }
-
-    #[inline(always)]
-    pub fn try_lock(&self) -> Option<LockGuard<'_, T>> {
-        self.0.try_borrow_mut().ok()
-    }
-
-    #[inline(always)]
-    #[track_caller]
-    pub fn lock(&self) -> LockGuard<'_, T> {
-        self.0.borrow_mut()
-    }
+#[derive(Clone, Copy, PartialEq)]
+pub enum Mode {
+    NoSync,
+    Sync,
 }
 
-/// A guard holding mutable access to a `Lock` which is in a locked state.
-#[cfg(parallel_compiler)]
-#[must_use = "if unused the Lock will immediately unlock"]
-pub struct LockGuard<'a, T> {
-    lock: &'a Lock<T>,
-    marker: PhantomData<&'a mut T>,
-}
+mod maybe_sync {
+    use super::Mode;
+    use crate::sync::mode;
+    #[cfg(parallel_compiler)]
+    use crate::sync::{DynSend, DynSync};
+    use parking_lot::lock_api::RawMutex as _;
+    use parking_lot::RawMutex;
+    use std::cell::Cell;
+    use std::cell::UnsafeCell;
+    use std::intrinsics::unlikely;
+    use std::marker::PhantomData;
+    use std::mem::ManuallyDrop;
+    use std::ops::{Deref, DerefMut};
 
-#[cfg(parallel_compiler)]
-impl<'a, T: 'a> Deref for LockGuard<'a, T> {
-    type Target = T;
-    #[inline]
-    fn deref(&self) -> &T {
-        // SAFETY: We have shared access to the mutable access owned by this type,
-        // so we can give out a shared reference.
-        unsafe { &*self.lock.data.get() }
+    /// A guard holding mutable access to a `Lock` which is in a locked state.
+    #[must_use = "if unused the Lock will immediately unlock"]
+    pub struct LockGuard<'a, T> {
+        lock: &'a Lock<T>,
+        marker: PhantomData<&'a mut T>,
+
+        /// The syncronization mode of the lock. This is explicitly passed to let LLVM relate it
+        /// to the original lock operation.
+        mode: Mode,
     }
-}
 
-#[cfg(parallel_compiler)]
-impl<'a, T: 'a> DerefMut for LockGuard<'a, T> {
-    #[inline]
-    fn deref_mut(&mut self) -> &mut T {
-        // SAFETY: We have mutable access to the data so we can give out a mutable reference.
-        unsafe { &mut *self.lock.data.get() }
-    }
-}
-
-#[cfg(parallel_compiler)]
-impl<'a, T: 'a> Drop for LockGuard<'a, T> {
-    #[inline]
-    fn drop(&mut self) {
-        // SAFETY: We know that the lock is in a locked
-        // state because it is a invariant of this type.
-        unsafe { self.lock.raw.unlock() };
-    }
-}
-
-#[cfg(parallel_compiler)]
-union LockRawUnion {
-    /// Indicates if the cell is locked. Only used if `LockRaw.sync` is false.
-    cell: ManuallyDrop<Cell<bool>>,
-
-    /// A lock implementation that's only used if `LockRaw.sync` is true.
-    lock: ManuallyDrop<parking_lot::RawMutex>,
-}
-
-/// A raw lock which only uses synchronization if `might_be_dyn_thread_safe` is true.
-/// It contains no associated data and is used in the implementation of `Lock` which does have such data.
-///
-/// A manual implementation of a tagged union is used with the `sync` field and the `LockRawUnion` instead
-/// of using enums as it results in better code generation.
-#[cfg(parallel_compiler)]
-struct LockRaw {
-    /// Indicates if synchronization is used via `opt.lock` if true,
-    /// or if a non-thread safe cell is used via `opt.cell`. This is set on initialization and never changed.
-    sync: bool,
-    opt: LockRawUnion,
-}
-
-#[cfg(parallel_compiler)]
-impl LockRaw {
-    fn new() -> Self {
-        if unlikely(super::mode::might_be_dyn_thread_safe()) {
-            // Create the lock with synchronization enabled using the `RawMutex` type.
-            LockRaw {
-                sync: true,
-                opt: LockRawUnion { lock: ManuallyDrop::new(parking_lot::RawMutex::INIT) },
-            }
-        } else {
-            // Create the lock with synchronization disabled.
-            LockRaw { sync: false, opt: LockRawUnion { cell: ManuallyDrop::new(Cell::new(false)) } }
+    impl<'a, T: 'a> Deref for LockGuard<'a, T> {
+        type Target = T;
+        #[inline]
+        fn deref(&self) -> &T {
+            // SAFETY: We have shared access to the mutable access owned by this type,
+            // so we can give out a shared reference.
+            unsafe { &*self.lock.data.get() }
         }
     }
 
-    #[inline(always)]
-    fn try_lock(&self) -> bool {
-        // SAFETY: This is safe since the union fields are used in accordance with `self.sync`.
-        unsafe {
-            if likely(!self.sync) {
-                if self.opt.cell.get() {
-                    false
-                } else {
-                    self.opt.cell.set(true);
-                    true
+    impl<'a, T: 'a> DerefMut for LockGuard<'a, T> {
+        #[inline]
+        fn deref_mut(&mut self) -> &mut T {
+            // SAFETY: We have mutable access to the data so we can give out a mutable reference.
+            unsafe { &mut *self.lock.data.get() }
+        }
+    }
+
+    impl<'a, T: 'a> Drop for LockGuard<'a, T> {
+        #[inline]
+        fn drop(&mut self) {
+            // SAFETY (union access): We get `self.mode` from the lock operation so it is consistent
+            // with the `lock.mode` state. This means we access the right union fields.
+            match self.mode {
+                Mode::NoSync => {
+                    let cell = unsafe { &self.lock.mode_union.no_sync };
+                    debug_assert_eq!(cell.get(), true);
+                    cell.set(false);
                 }
-            } else {
-                self.opt.lock.try_lock()
+                // SAFETY (unlock): We know that the lock is locked as this type is a proof of that.
+                Mode::Sync => unsafe { self.lock.mode_union.sync.unlock() },
             }
         }
     }
 
-    #[inline(always)]
-    fn lock(&self) {
-        if super::ERROR_CHECKING {
-            // We're in the debugging mode, so assert that the lock is not held so we
-            // get a panic instead of waiting for the lock.
-            assert_eq!(self.try_lock(), true, "lock must not be hold");
-        } else {
-            // SAFETY: This is safe since the union fields are used in accordance with `self.sync`.
-            unsafe {
-                if likely(!self.sync) {
-                    if unlikely(self.opt.cell.replace(true)) {
-                        cold_path(|| panic!("lock was already held"))
+    union ModeUnion {
+        /// Indicates if the cell is locked. Only used if `Lock.mode` is `NoSync`.
+        no_sync: ManuallyDrop<Cell<bool>>,
+
+        /// A lock implementation that's only used if `Lock.mode` is `Sync`.
+        sync: ManuallyDrop<RawMutex>,
+    }
+
+    /// The value representing a locked state for the `Cell`.
+    const LOCKED: bool = true;
+
+    /// A lock which only uses synchronization if `might_be_dyn_thread_safe` is true.
+    /// It implements `DynSend` and `DynSync` instead of the typical `Send` and `Sync`.
+    pub struct Lock<T> {
+        /// Indicates if synchronization is used via `mode_union.sync` if it's `Sync`, or if a
+        /// not thread safe cell is used via `mode_union.no_sync` if it's `NoSync`.
+        /// This is set on initialization and never changed.
+        mode: Mode,
+
+        mode_union: ModeUnion,
+        data: UnsafeCell<T>,
+    }
+
+    impl<T> Lock<T> {
+        #[inline(always)]
+        pub fn new(inner: T) -> Self {
+            let (mode, mode_union) = if unlikely(mode::might_be_dyn_thread_safe()) {
+                // Create the lock with synchronization enabled using the `RawMutex` type.
+                (Mode::Sync, ModeUnion { sync: ManuallyDrop::new(RawMutex::INIT) })
+            } else {
+                // Create the lock with synchronization disabled.
+                (Mode::NoSync, ModeUnion { no_sync: ManuallyDrop::new(Cell::new(!LOCKED)) })
+            };
+            Lock { mode, mode_union, data: UnsafeCell::new(inner) }
+        }
+
+        #[inline(always)]
+        pub fn into_inner(self) -> T {
+            self.data.into_inner()
+        }
+
+        #[inline(always)]
+        pub fn get_mut(&mut self) -> &mut T {
+            self.data.get_mut()
+        }
+
+        #[inline(always)]
+        pub fn try_lock(&self) -> Option<LockGuard<'_, T>> {
+            let mode = self.mode;
+            // SAFETY: This is safe since the union fields are used in accordance with `self.mode`.
+            match mode {
+                Mode::NoSync => {
+                    let cell = unsafe { &self.mode_union.no_sync };
+                    let was_unlocked = cell.get() != LOCKED;
+                    if was_unlocked {
+                        cell.set(LOCKED);
                     }
-                } else {
-                    self.opt.lock.lock();
+                    was_unlocked
+                }
+                Mode::Sync => unsafe { self.mode_union.sync.try_lock() },
+            }
+            .then(|| LockGuard { lock: self, marker: PhantomData, mode })
+        }
+
+        /// This acquires the lock assuming syncronization is in a specific mode.
+        ///
+        /// Safety
+        /// This method must only be called with `Mode::Sync` if `might_be_dyn_thread_safe` was
+        /// true on lock creation.
+        #[inline(always)]
+        #[track_caller]
+        pub unsafe fn lock_assume(&self, mode: Mode) -> LockGuard<'_, T> {
+            #[inline(never)]
+            #[track_caller]
+            #[cold]
+            fn lock_held() -> ! {
+                panic!("lock was already held")
+            }
+
+            // SAFETY: This is safe since the union fields are used in accordance with `mode`
+            // which also must match `self.mode` due to the safety precondition.
+            unsafe {
+                match mode {
+                    Mode::NoSync => {
+                        if unlikely(self.mode_union.no_sync.replace(LOCKED) == LOCKED) {
+                            lock_held()
+                        }
+                    }
+                    Mode::Sync => self.mode_union.sync.lock(),
                 }
             }
+            LockGuard { lock: self, marker: PhantomData, mode }
+        }
+
+        #[inline(always)]
+        #[track_caller]
+        pub fn lock(&self) -> LockGuard<'_, T> {
+            unsafe { self.lock_assume(self.mode) }
         }
     }
 
-    /// This unlocks the lock.
-    ///
-    /// Safety
-    /// This method may only be called if the lock is currently held.
-    #[inline(always)]
-    unsafe fn unlock(&self) {
-        // SAFETY: The union use is safe since the union fields are used in accordance with
-        // `self.sync` and the `unlock` method precondition is upheld by the caller.
-        unsafe {
-            if likely(!self.sync) {
-                debug_assert_eq!(self.opt.cell.get(), true);
-                self.opt.cell.set(false);
-            } else {
-                self.opt.lock.unlock();
-            }
+    #[cfg(parallel_compiler)]
+    unsafe impl<T: DynSend> DynSend for Lock<T> {}
+    #[cfg(parallel_compiler)]
+    unsafe impl<T: DynSend> DynSync for Lock<T> {}
+}
+
+mod no_sync {
+    use super::Mode;
+    use std::cell::RefCell;
+
+    pub use std::cell::RefMut as LockGuard;
+
+    pub struct Lock<T>(RefCell<T>);
+
+    impl<T> Lock<T> {
+        #[inline(always)]
+        pub fn new(inner: T) -> Self {
+            Lock(RefCell::new(inner))
         }
-    }
-}
 
-/// A lock which only uses synchronization if `might_be_dyn_thread_safe` is true.
-/// It implements `DynSend` and `DynSync` instead of the typical `Send` and `Sync`.
-#[cfg(parallel_compiler)]
-pub struct Lock<T> {
-    raw: LockRaw,
-    data: UnsafeCell<T>,
-}
+        #[inline(always)]
+        pub fn into_inner(self) -> T {
+            self.0.into_inner()
+        }
 
-#[cfg(parallel_compiler)]
-impl<T> Lock<T> {
-    #[inline(always)]
-    pub fn new(inner: T) -> Self {
-        Lock { raw: LockRaw::new(), data: UnsafeCell::new(inner) }
-    }
+        #[inline(always)]
+        pub fn get_mut(&mut self) -> &mut T {
+            self.0.get_mut()
+        }
 
-    #[inline(always)]
-    pub fn into_inner(self) -> T {
-        self.data.into_inner()
-    }
+        #[inline(always)]
+        pub fn try_lock(&self) -> Option<LockGuard<'_, T>> {
+            self.0.try_borrow_mut().ok()
+        }
 
-    #[inline(always)]
-    pub fn get_mut(&mut self) -> &mut T {
-        self.data.get_mut()
-    }
+        #[inline(always)]
+        #[track_caller]
+        // This is unsafe to match the API for the `parallel_compiler` case.
+        pub unsafe fn lock_assume(&self, _mode: Mode) -> LockGuard<'_, T> {
+            self.0.borrow_mut()
+        }
 
-    #[inline(always)]
-    pub fn try_lock(&self) -> Option<LockGuard<'_, T>> {
-        if self.raw.try_lock() { Some(LockGuard { lock: self, marker: PhantomData }) } else { None }
-    }
-
-    #[inline(always)]
-    pub fn lock(&self) -> LockGuard<'_, T> {
-        self.raw.lock();
-        LockGuard { lock: self, marker: PhantomData }
+        #[inline(always)]
+        #[track_caller]
+        pub fn lock(&self) -> LockGuard<'_, T> {
+            self.0.borrow_mut()
+        }
     }
 }
 
@@ -244,12 +249,13 @@ impl<T> Lock<T> {
     }
 }
 
-#[cfg(parallel_compiler)]
-unsafe impl<T: DynSend> DynSend for Lock<T> {}
-#[cfg(parallel_compiler)]
-unsafe impl<T: DynSend> DynSync for Lock<T> {}
+impl<T: Default> Default for Lock<T> {
+    #[inline]
+    fn default() -> Self {
+        Lock::new(T::default())
+    }
+}
 
-#[cfg(parallel_compiler)]
 impl<T: fmt::Debug> fmt::Debug for Lock<T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self.try_lock() {
@@ -267,10 +273,3 @@ impl<T: fmt::Debug> fmt::Debug for Lock<T> {
         }
     }
 }
-
-impl<T: Default> Default for Lock<T> {
-    #[inline]
-    fn default() -> Self {
-        Lock::new(T::default())
-    }
-}

compiler/rustc_query_system/src/dep_graph/graph.rs

@@ -629,12 +629,7 @@ impl<K: DepKind> DepGraphData<K> {
         if let Some(prev_index) = self.previous.node_to_index_opt(dep_node) {
             self.current.prev_index_to_index.lock()[prev_index]
         } else {
-            self.current
-                .new_node_to_index
-                .get_shard_by_value(dep_node)
-                .lock()
-                .get(dep_node)
-                .copied()
+            self.current.new_node_to_index.lock_shard_by_value(dep_node).get(dep_node).copied()
         }
     }
 
@@ -1201,8 +1196,7 @@ impl<K: DepKind> CurrentDepGraph<K> {
         edges: EdgesVec,
         current_fingerprint: Fingerprint,
     ) -> DepNodeIndex {
-        let dep_node_index = match self.new_node_to_index.get_shard_by_value(&key).lock().entry(key)
-        {
+        let dep_node_index = match self.new_node_to_index.lock_shard_by_value(&key).entry(key) {
             Entry::Occupied(entry) => *entry.get(),
             Entry::Vacant(entry) => {
                 let dep_node_index =
@@ -1328,7 +1322,7 @@ impl<K: DepKind> CurrentDepGraph<K> {
     ) {
         let node = &prev_graph.index_to_node(prev_index);
         debug_assert!(
-            !self.new_node_to_index.get_shard_by_value(node).lock().contains_key(node),
+            !self.new_node_to_index.lock_shard_by_value(node).contains_key(node),
             "node from previous graph present in new node collection"
         );
     }

compiler/rustc_query_system/src/query/caches.rs

@@ -55,7 +55,7 @@ where
     #[inline(always)]
     fn lookup(&self, key: &K) -> Option<(V, DepNodeIndex)> {
         let key_hash = sharded::make_hash(key);
-        let lock = self.cache.get_shard_by_hash(key_hash).lock();
+        let lock = self.cache.lock_shard_by_hash(key_hash);
         let result = lock.raw_entry().from_key_hashed_nocheck(key_hash, key);
 
         if let Some((_, value)) = result { Some(*value) } else { None }
@@ -63,7 +63,7 @@ where
 
     #[inline]
     fn complete(&self, key: K, value: V, index: DepNodeIndex) {
-        let mut lock = self.cache.get_shard_by_value(&key).lock();
+        let mut lock = self.cache.lock_shard_by_value(&key);
         // We may be overwriting another value. This is all right, since the dep-graph
         // will check that the fingerprint matches.
         lock.insert(key, (value, index));
@@ -148,13 +148,13 @@ where
 
     #[inline(always)]
     fn lookup(&self, key: &K) -> Option<(V, DepNodeIndex)> {
-        let lock = self.cache.get_shard_by_hash(key.index() as u64).lock();
+        let lock = self.cache.lock_shard_by_hash(key.index() as u64);
         if let Some(Some(value)) = lock.get(*key) { Some(*value) } else { None }
     }
 
     #[inline]
     fn complete(&self, key: K, value: V, index: DepNodeIndex) {
-        let mut lock = self.cache.get_shard_by_hash(key.index() as u64).lock();
+        let mut lock = self.cache.lock_shard_by_hash(key.index() as u64);
         lock.insert(key, (value, index));
     }
 

compiler/rustc_query_system/src/query/plumbing.rs

@@ -158,7 +158,7 @@ where
         cache.complete(key, result, dep_node_index);
 
         let job = {
-            let mut lock = state.active.get_shard_by_value(&key).lock();
+            let mut lock = state.active.lock_shard_by_value(&key);
             match lock.remove(&key).unwrap() {
                 QueryResult::Started(job) => job,
                 QueryResult::Poisoned => panic!(),
@@ -180,7 +180,7 @@ where
         // Poison the query so jobs waiting on it panic.
         let state = self.state;
         let job = {
-            let mut shard = state.active.get_shard_by_value(&self.key).lock();
+            let mut shard = state.active.lock_shard_by_value(&self.key);
             let job = match shard.remove(&self.key).unwrap() {
                 QueryResult::Started(job) => job,
                 QueryResult::Poisoned => panic!(),
@@ -303,7 +303,7 @@ where
     Qcx: QueryContext,
 {
     let state = query.query_state(qcx);
-    let mut state_lock = state.active.get_shard_by_value(&key).lock();
+    let mut state_lock = state.active.lock_shard_by_value(&key);
 
     // For the parallel compiler we need to check both the query cache and query state structures
     // while holding the state lock to ensure that 1) the query has not yet completed and 2) the