hashmap.h

/*
 * Fermat
 *
 * Copyright (c) 2016-2019, NVIDIA CORPORATION. All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *    * Neither the name of the NVIDIA CORPORATION nor the
 *      names of its contributors may be used to endorse or promote products
 *      derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NVIDIA CORPORATION BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#pragma once

#include "buffers.h"

struct DeviceHashTable
{
    void resize(const uint32 N)
    {
        m_keys.alloc(N);
        m_slots.alloc(N);
        m_unique.alloc(N);
        m_size.alloc(1);
    }

    uint64 needed_bytes(const uint32 N) const
    {
        return (sizeof(uint64) * 2 + sizeof(uint32)) * N + sizeof(uint32);
    }

    void clear()
    {
        // initialize the cache size
        m_size.set(0, 0);

        // initialize the cache keys
        cudaMemset(m_keys.ptr(),  0xFFu, m_keys.sizeInBytes());
        cudaMemset(m_slots.ptr(), 0xFFu, m_slots.sizeInBytes());
    }

    uint32 size() const
    {
        return m_size[0];
    }

    DomainBuffer<CUDA_BUFFER, uint64>   m_keys;
    DomainBuffer<CUDA_BUFFER, uint64>   m_unique;
    DomainBuffer<CUDA_BUFFER, uint32>   m_slots;
    DomainBuffer<CUDA_BUFFER, uint32>   m_size;
};