J9SegmentAllocator.hpp

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 * Copyright (c) 2000, 2016 IBM Corp. and others
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 * This program and the accompanying materials are made available under
 * the terms of the Eclipse Public License 2.0 which accompanies this
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 * is available at https://www.apache.org/licenses/LICENSE-2.0.
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 * This Source Code may also be made available under the following
 * Secondary Licenses when the conditions for such availability set
 * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
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 * OpenJDK Assembly Exception [2].
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#ifndef J9_SEGMENT_ALLOCATOR_HPP
#define J9_SEGMENT_ALLOCATOR_HPP

#include <stddef.h>
#include <stdint.h>
#include <new>
#include "env/J9SegmentProvider.hpp"

extern "C" {
struct J9JavaVM;
struct J9MemorySegment;
}

namespace J9 {

class SegmentAllocator : public J9SegmentProvider
   {
public:
   SegmentAllocator(int32_t segmentType, J9JavaVM &javaVM) throw();
   ~SegmentAllocator() throw();
   J9MemorySegment &allocate(const size_t segmentSize);
   J9MemorySegment *allocate(const size_t segmentSize, const std::nothrow_t &tag) throw();
   void deallocate(J9MemorySegment &unusedSegment) throw();

   J9MemorySegment &request(size_t segmentSize);
   void release(J9MemorySegment &unusedSegment) throw();

   size_t pageSize() throw();
   size_t pageAlign(const size_t requestedSize) throw();

private:
   void preventAllocationOfBTLMemory(J9MemorySegment * &segment, J9JavaVM * javaVM, int32_t segmentType);

   const int32_t _segmentType;
   J9JavaVM &_javaVM;
   };

}

#endif // SEGMENT_ALLOCATOR_HPP