Move Volatile to shared (#22523)

* Move Volatile to shared

This largely takes corert's implementation, which uses Unsafe.As and volatile fields.

We could investigate also removing the JIT's replacements subsequently.

* Add [Intrinsic] attributes

1 files changed, 0 insertions, 404 deletions

diff --git a/src/System.Private.CoreLib/src/System/Threading/Volatile.cs b/src/System.Private.CoreLib/src/System/Threading/Volatile.cs
deleted file mode 100644
index 6aac8d63cd..0000000000
--- a/src/System.Private.CoreLib/src/System/Threading/Volatile.cs
+++ /dev/null
@@ -1,404 +0,0 @@
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-// See the LICENSE file in the project root for more information.
-
-//
-
-using System;
-using System.Runtime.InteropServices;
-using System.Runtime.Versioning;
-using System.Runtime.ConstrainedExecution;
-using System.Runtime.CompilerServices;
-using System.Runtime;
-using System.Security;
-
-namespace System.Threading
-{
-    //
-    // Methods for accessing memory with volatile semantics.  These are preferred over Thread.VolatileRead
-    // and Thread.VolatileWrite, as these are implemented more efficiently.
-    //
-    // (We cannot change the implementations of Thread.VolatileRead/VolatileWrite without breaking code
-    // that relies on their overly-strong ordering guarantees.)
-    //
-    // The actual implementations of these methods are typically supplied by the VM at JIT-time, because C# does
-    // not allow us to express a volatile read/write from/to a byref arg.
-    // See getILIntrinsicImplementationForVolatile() in jitinterface.cpp.
-    //
-    public static class Volatile
-    {
-        [System.Runtime.Versioning.NonVersionable]
-        public static bool Read(ref bool location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static sbyte Read(ref sbyte location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static byte Read(ref byte location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static short Read(ref short location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static ushort Read(ref ushort location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static int Read(ref int location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static uint Read(ref uint location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-#if BIT64
-        [System.Runtime.Versioning.NonVersionable]
-        public static long Read(ref long location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static ulong Read(ref ulong location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-#else
-        public static long Read(ref long location)
-        {
-            //
-            // On 32-bit machines, we use this implementation, since an ordinary volatile read
-            // would not be atomic.
-            //
-            // On 64-bit machines, the VM will replace this with a more efficient implementation.
-            //
-            return Interlocked.CompareExchange(ref location, 0, 0);
-        }
-
-        [CLSCompliant(false)]
-        public static ulong Read(ref ulong location)
-        {
-            unsafe
-            {
-                //
-                // There is no overload of Interlocked.Exchange that accepts a ulong.  So we have
-                // to do some pointer tricks to pass our arguments to the overload that takes a long.
-                //
-                fixed (ulong* pLocation = &location)
-                {
-                    return (ulong)Interlocked.CompareExchange(ref *(long*)pLocation, 0, 0);
-                }
-            }
-        }
-#endif
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static IntPtr Read(ref IntPtr location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static UIntPtr Read(ref UIntPtr location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static float Read(ref float location)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static double Read(ref double location)
-        {
-            //
-            // On 32-bit machines, we use this implementation, since an ordinary volatile read
-            // would not be atomic.
-            //
-            // On 64-bit machines, the VM will replace this with a more efficient implementation.
-            //
-            return Interlocked.CompareExchange(ref location, 0, 0);
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static T Read<T>(ref T location) where T : class
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            var value = location;
-            Interlocked.MemoryBarrier();
-            return value;
-        }
-
-
-
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref bool location, bool value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref sbyte location, sbyte value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref byte location, byte value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref short location, short value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref ushort location, ushort value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref int location, int value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref uint location, uint value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-#if BIT64
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref long location, long value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref ulong location, ulong value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-#else
-        public static void Write(ref long location, long value)
-        {
-            //
-            // On 32-bit machines, we use this implementation, since an ordinary volatile write 
-            // would not be atomic.
-            //
-            // On 64-bit machines, the VM will replace this with a more efficient implementation.
-            //
-            Interlocked.Exchange(ref location, value);
-        }
-
-        [CLSCompliant(false)]
-        public static void Write(ref ulong location, ulong value)
-        {
-            //
-            // On 32-bit machines, we use this implementation, since an ordinary volatile write 
-            // would not be atomic.
-            //
-            // On 64-bit machines, the VM will replace this with a more efficient implementation.
-            //
-            unsafe
-            {
-                //
-                // There is no overload of Interlocked.Exchange that accepts a ulong.  So we have
-                // to do some pointer tricks to pass our arguments to the overload that takes a long.
-                //
-                fixed (ulong* pLocation = &location)
-                {
-                    Interlocked.Exchange(ref *(long*)pLocation, (long)value);
-                }
-            }
-        }
-#endif
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref IntPtr location, IntPtr value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [CLSCompliant(false)]
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref UIntPtr location, UIntPtr value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref float location, float value)
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write(ref double location, double value)
-        {
-            //
-            // On 32-bit machines, we use this implementation, since an ordinary volatile write 
-            // would not be atomic.
-            //
-            // On 64-bit machines, the VM will replace this with a more efficient implementation.
-            //
-            Interlocked.Exchange(ref location, value);
-        }
-
-        [System.Runtime.Versioning.NonVersionable]
-        public static void Write<T>(ref T location, T value) where T : class
-        {
-            // 
-            // The VM will replace this with a more efficient implementation.
-            //
-            Interlocked.MemoryBarrier();
-            location = value;
-        }
-    }
-}