use thread-safe RwLock

Author: SparrowLii

compiler/rustc_data_structures/src/sync.rs

@@ -246,16 +246,8 @@ cfg_if! {
 
         pub type MetadataRef = OwnedSlice;
 
-        pub use std::cell::Ref as ReadGuard;
-        pub use std::cell::Ref as MappedReadGuard;
-        pub use std::cell::RefMut as WriteGuard;
-        pub use std::cell::RefMut as MappedWriteGuard;
-        pub use std::cell::RefMut as MappedLockGuard;
-
         pub use std::cell::OnceCell;
 
-        use std::cell::RefCell as InnerRwLock;
-
         pub type MTLockRef<'a, T> = &'a mut MTLock<T>;
 
         #[derive(Debug, Default)]
@@ -299,13 +291,6 @@ cfg_if! {
         pub use std::marker::Send as Send;
         pub use std::marker::Sync as Sync;
 
-        pub use parking_lot::RwLockReadGuard as ReadGuard;
-        pub use parking_lot::MappedRwLockReadGuard as MappedReadGuard;
-        pub use parking_lot::RwLockWriteGuard as WriteGuard;
-        pub use parking_lot::MappedRwLockWriteGuard as MappedWriteGuard;
-
-        pub use parking_lot::MappedMutexGuard as MappedLockGuard;
-
         pub use std::sync::OnceLock as OnceCell;
 
         pub use std::sync::atomic::{AtomicBool, AtomicUsize, AtomicU32, AtomicU64};
@@ -342,8 +327,6 @@ cfg_if! {
             }
         }
 
-        use parking_lot::RwLock as InnerRwLock;
-
         use std::thread;
 
         #[inline]
@@ -508,14 +491,22 @@ cfg_if! {
 
         pub type MetadataRef = OwnedSlice;
 
-        /// This makes locks panic if they are already held.
-        /// It is only useful when you are running in a single thread
-        const ERROR_CHECKING: bool = false;
     }
 }
 
 pub use std::sync::Arc as Lrc;
 
+use parking_lot::RwLock as InnerRwLock;
+
+pub use parking_lot::MappedRwLockReadGuard as MappedReadGuard;
+pub use parking_lot::MappedRwLockWriteGuard as MappedWriteGuard;
+pub use parking_lot::RwLockReadGuard as ReadGuard;
+pub use parking_lot::RwLockWriteGuard as WriteGuard;
+
+/// This makes locks panic if they are already held.
+/// It is only useful when you are running in a single thread
+const ERROR_CHECKING: bool = false;
+
 pub unsafe trait DynSend {}
 pub unsafe trait DynSync {}
 
@@ -742,14 +733,6 @@ impl<T> RwLock<T> {
         self.0.get_mut()
     }
 
-    #[cfg(not(parallel_compiler))]
-    #[inline(always)]
-    #[track_caller]
-    pub fn read(&self) -> ReadGuard<'_, T> {
-        self.0.borrow()
-    }
-
-    #[cfg(parallel_compiler)]
     #[inline(always)]
     pub fn read(&self) -> ReadGuard<'_, T> {
         if ERROR_CHECKING {
@@ -765,26 +748,11 @@ impl<T> RwLock<T> {
         f(&*self.read())
     }
 
-    #[cfg(not(parallel_compiler))]
-    #[inline(always)]
-    pub fn try_write(&self) -> Result<WriteGuard<'_, T>, ()> {
-        self.0.try_borrow_mut().map_err(|_| ())
-    }
-
-    #[cfg(parallel_compiler)]
     #[inline(always)]
     pub fn try_write(&self) -> Result<WriteGuard<'_, T>, ()> {
         self.0.try_write().ok_or(())
     }
 
-    #[cfg(not(parallel_compiler))]
-    #[inline(always)]
-    #[track_caller]
-    pub fn write(&self) -> WriteGuard<'_, T> {
-        self.0.borrow_mut()
-    }
-
-    #[cfg(parallel_compiler)]
     #[inline(always)]
     pub fn write(&self) -> WriteGuard<'_, T> {
         if ERROR_CHECKING {
@@ -812,13 +780,6 @@ impl<T> RwLock<T> {
         self.write()
     }
 
-    #[cfg(not(parallel_compiler))]
-    #[inline(always)]
-    pub fn leak(&self) -> &T {
-        ReadGuard::leak(self.read())
-    }
-
-    #[cfg(parallel_compiler)]
     #[inline(always)]
     pub fn leak(&self) -> &T {
         let guard = self.read();