/*****************************************************************************

 * Copyright (C) 2013-2020 MulticoreWare, Inc

 *

 * Authors: Steve Borho <steve@borho.org>

 *          Min Chen <chenm003@163.com>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program 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 for more details.

 *

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

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02111, USA.

 *

 * This program is also available under a commercial proprietary license.

 * For more information, contact us at license @ x265.com

 *****************************************************************************/

#include "threadpool.h"

#include "threading.h"

#include "wavefront.h"

#include "common.h"

namespace X265_NS {

// x265 private namespace

bool WaveFront::init(int numRows)

{

    m_numRows = numRows;

    m_numWords = (numRows + 31) >> 5;

    m_internalDependencyBitmap = X265_MALLOC(uint32_t, m_numWords);

    if (m_internalDependencyBitmap)

        memset((void*)m_internalDependencyBitmap, 0, sizeof(uint32_t) * m_numWords);

    m_externalDependencyBitmap = X265_MALLOC(uint32_t, m_numWords);

    if (m_externalDependencyBitmap)

        memset((void*)m_externalDependencyBitmap, 0, sizeof(uint32_t) * m_numWords);

    m_row_to_idx = X265_MALLOC(uint32_t, m_numRows);

    m_idx_to_row = X265_MALLOC(uint32_t, m_numRows);

    return m_internalDependencyBitmap && m_externalDependencyBitmap;

}

WaveFront::~WaveFront()

{

    x265_free((void*)m_row_to_idx);

    x265_free((void*)m_idx_to_row);

    x265_free((void*)m_internalDependencyBitmap);

    x265_free((void*)m_externalDependencyBitmap);

}

void WaveFront::clearEnabledRowMask()

{

    memset((void*)m_externalDependencyBitmap, 0, sizeof(uint32_t) * m_numWords);

    memset((void*)m_internalDependencyBitmap, 0, sizeof(uint32_t) * m_numWords);

}

void WaveFront::enqueueRow(int row)

{

    uint32_t bit = 1 << (row & 31);

    ATOMIC_OR(&m_internalDependencyBitmap[row >> 5], bit);

}

void WaveFront::enableRow(int row)

{

    uint32_t bit = 1 << (row & 31);

    ATOMIC_OR(&m_externalDependencyBitmap[row >> 5], bit);

}

void WaveFront::enableAllRows()

{

    memset((void*)m_externalDependencyBitmap, ~0, sizeof(uint32_t) * m_numWords);

}

bool WaveFront::dequeueRow(int row)

{

    uint32_t bit = 1 << (row & 31);

    return !!(ATOMIC_AND(&m_internalDependencyBitmap[row >> 5], ~bit) & bit);

}

void WaveFront::findJob(int threadId)

{

    unsigned long id;

    /* Loop over each word until all available rows are finished */

    for (int w = 0; w < m_numWords; w++)

    {

        uint32_t oldval = m_internalDependencyBitmap[w] & m_externalDependencyBitmap[w];

        while (oldval)

        {

            CTZ(id, oldval);

            uint32_t bit = 1 << id;

            if (ATOMIC_AND(&m_internalDependencyBitmap[w], ~bit) & bit)

            {

                /* we cleared the bit, we get to process the row */

                processRow(w * 32 + id, threadId);

                m_helpWanted = true;

                return; /* check for a higher priority task */

            }

            oldval = m_internalDependencyBitmap[w] & m_externalDependencyBitmap[w];

        }

    }

    m_helpWanted = false;

}

}