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diff --git a/src/inc/memoryrange.h b/src/inc/memoryrange.h
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+// 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.
+//*****************************************************************************
+// MemoryRange.h
+//
+// defines the code:MemoryRange class.
+//*****************************************************************************
+
+#ifndef _memory_range_h
+#define _memory_range_h
+
+#include "daccess.h"
+
+// MemoryRange is a descriptor of a memory range. This groups (pointer + size).
+// 
+// Some key qualities:
+// - simple!
+// - Not mutable
+// - blitabble descriptor which can be useful for out-of-process tools like the debugger.
+// - no ownership semantics. 
+// - no manipulation, growing semantics. 
+// - no memory marshalling, allocation, copying. etc.
+// - can be efficiently passed / copied / returned by value 
+// 
+// This class has general value as an abstraction to group pointer and size together. It also has significant
+// value to the debugger. An expected design pattern is that other mutable complex data structures (eg,
+// code:SBuffer, code:CGrowableStream) will provide an accessor to expose their underlying storage as a
+// MemoryRange to debugger. This mirrors the Debugger's code:TargetBuffer data structure, but as a 
+// general-purpose VM utility versus a debugger right-side data structure.  
+
+// 
+class MemoryRange
+{
+public:
+    // Constructor to create a memory range around a (start address, size) pair.
+    MemoryRange() :
+        m_pStartAddress(NULL),
+        m_cbBytes(0)
+    { 
+        SUPPORTS_DAC;
+    }
+
+    MemoryRange(PTR_VOID pStartAddress, SIZE_T cbBytes) : 
+        m_pStartAddress(pStartAddress),
+        m_cbBytes(cbBytes)
+    { 
+        SUPPORTS_DAC;
+    }
+
+    // Note: use compiler-default copy ctor and assignment operator 
+
+
+
+    // Check whether a pointer is in the memory range represented by this instance.
+    BOOL IsInRange(PTR_VOID pAddress) const
+    {
+        LIMITED_METHOD_DAC_CONTRACT;
+
+        return (dac_cast<TADDR>(pAddress) - dac_cast<TADDR>(m_pStartAddress)) < m_cbBytes;
+    }
+
+    // Check whether a pointer is in the memory range represented by this instance.
+    BOOL IsInRange(TADDR pAddress) const
+    {
+        LIMITED_METHOD_DAC_CONTRACT;
+
+        return (pAddress - dac_cast<TADDR>(m_pStartAddress)) < m_cbBytes;
+    }
+
+    // Get the starting address.
+    PTR_VOID StartAddress() const
+    {
+        SUPPORTS_DAC;
+        return m_pStartAddress;
+    }
+
+    // Get the size of the range in bytes
+    SIZE_T Size() const
+    {
+        SUPPORTS_DAC;
+        return m_cbBytes;
+    }
+
+private:    
+    // The start of the memory range.
+    PTR_VOID const m_pStartAddress;
+
+    // The size of the memory range in bytes.
+    // This is s SIZE_T so that it can describe any memory range in the process (for example, larger than 4gb on 64-bit machines)
+    const SIZE_T        m_cbBytes;
+
+};
+
+typedef ArrayDPTR(MemoryRange) ARRAY_PTR_MemoryRange;
+
+#endif // _memory_range_h
+