/*

 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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#ifndef SHARE_GC_SHARED_GCTHREADLOCALDATA_HPP

#define SHARE_GC_SHARED_GCTHREADLOCALDATA_HPP

#include "utilities/globalDefinitions.hpp"

// Thread local data area for GC-specific information. Each GC

// is free to decide the internal structure and contents of this

// area. It is represented as a 64-bit aligned opaque blob to

// avoid circular dependencies between Thread and all GCs. For

// the same reason, the size of the data area is hard coded to

// provide enough space for all current GCs. Adjust the size if

// needed, but avoid making it excessively large as it adds to

// the memory overhead of creating a thread.

//

// Use Thread::gc_data<T>() to access the data, where T is the

// GC-specific type describing the structure of the data. GCs

// should consider placing frequently accessed fields first in

// T, so that field offsets relative to Thread are small, which

// often allows for a more compact instruction encoding.

typedef uint64_t GCThreadLocalData[18]; // 144 bytes

#endif // SHARE_GC_SHARED_GCTHREADLOCALDATA_HPP