1 files changed, 101 insertions, 0 deletions
diff --git a/src/gc/env/gcenv.interlocked.h b/src/gc/env/gcenv.interlocked.h
new file mode 100644
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+++ b/src/gc/env/gcenv.interlocked.h
@@ -0,0 +1,101 @@
+// 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.
+// Interlocked operations
+//
+
+#ifndef __GCENV_INTERLOCKED_H__
+#define __GCENV_INTERLOCKED_H__
+
+// Interlocked operations
+class Interlocked
+{
+public:
+
+    // Increment the value of the specified 32-bit variable as an atomic operation.
+    // Parameters:
+    //  addend - variable to be incremented
+    // Return:
+    //  The resulting incremented value
+    template<typename T>
+    static T Increment(T volatile *addend);
+
+    // Decrement the value of the specified 32-bit variable as an atomic operation.
+    // Parameters:
+    //  addend - variable to be decremented
+    // Return:
+    //  The resulting decremented value
+    template<typename T>
+    static T Decrement(T volatile *addend);
+
+    // Perform an atomic AND operation on the specified values values
+    // Parameters:
+    //  destination - the first operand and the destination
+    //  value       - second operand
+    template<typename T>
+    static void And(T volatile *destination, T value);
+
+    // Perform an atomic OR operation on the specified values values
+    // Parameters:
+    //  destination - the first operand and the destination
+    //  value       - second operand
+    template<typename T>
+    static void Or(T volatile *destination, T value);
+
+    // Set a 32-bit variable to the specified value as an atomic operation. 
+    // Parameters:
+    //  destination - value to be exchanged
+    //  value       - value to set the destination to
+    // Return:
+    //  The previous value of the destination
+    template<typename T>
+    static T Exchange(T volatile *destination, T value);
+
+    // Set a pointer variable to the specified value as an atomic operation.
+    // Parameters:
+    //  destination - value to be exchanged
+    //  value       - value to set the destination to
+    // Return:
+    //  The previous value of the destination
+    template <typename T>
+    static T ExchangePointer(T volatile * destination, T value);
+
+    template <typename T>
+    static T ExchangePointer(T volatile * destination, std::nullptr_t value);
+
+    // Perform an atomic addition of two 32-bit values and return the original value of the addend.
+    // Parameters:
+    //  addend - variable to be added to
+    //  value  - value to add
+    // Return:
+    //  The previous value of the addend
+    template<typename T>
+    static T ExchangeAdd(T volatile *addend, T value);
+
+    // Performs an atomic compare-and-exchange operation on the specified values. 
+    // Parameters:
+    //  destination - value to be exchanged
+    //  exchange    - value to set the destination to
+    //  comparand   - value to compare the destination to before setting it to the exchange.
+    //                The destination is set only if the destination is equal to the comparand.
+    // Return:
+    //  The original value of the destination
+    template<typename T>
+    static T CompareExchange(T volatile *destination, T exchange, T comparand);
+
+    // Performs an atomic compare-and-exchange operation on the specified pointers. 
+    // Parameters:
+    //  destination - value to be exchanged
+    //  exchange    - value to set the destination to
+    //  comparand   - value to compare the destination to before setting it to the exchange.
+    //                The destination is set only if the destination is equal to the comparand.
+    // Return:
+    //  The original value of the destination
+    template <typename T>
+    static T CompareExchangePointer(T volatile *destination, T exchange, T comparand);
+
+    template <typename T>
+    static T CompareExchangePointer(T volatile *destination, T exchange, std::nullptr_t comparand);
+};
+
+#endif // __GCENV_INTERLOCKED_H__