tagged.cc

来自「M5,一个功能强大的多处理器系统模拟器.很多针对处理器架构,性能的研究都使用它作」· CC 代码 · 共 71 行

/*
 * Copyright (c) 2005
 * The Regents of The University of Michigan
 * All Rights Reserved
 *
 * This code is part of the M5 simulator.
 *
 * Permission is granted to use, copy, create derivative works and
 * redistribute this software and such derivative works for any
 * purpose, so long as the copyright notice above, this grant of
 * permission, and the disclaimer below appear in all copies made; and
 * so long as the name of The University of Michigan is not used in
 * any advertising or publicity pertaining to the use or distribution
 * of this software without specific, written prior authorization.
 *
 * THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION FROM THE
 * UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY PURPOSE, AND
 * WITHOUT WARRANTY BY THE UNIVERSITY OF MICHIGAN OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE. THE REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE
 * LIABLE FOR ANY DAMAGES, INCLUDING DIRECT, SPECIAL, INDIRECT,
 * INCIDENTAL, OR CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM
 * ARISING OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN
 * IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGES.
 *
 * Authors: Ronald G. Dreslinski Jr
 */

/**
 * @file
 * Describes a tagged prefetcher based on template policies.
 */

#include "arch/isa_traits.hh"
#include "mem/cache/prefetch/tagged.hh"

TaggedPrefetcher::TaggedPrefetcher(const BaseCacheParams *p)
    : BasePrefetcher(p),
      latency(p->prefetch_latency), degree(p->prefetch_degree)
{
}

void
TaggedPrefetcher::
calculatePrefetch(PacketPtr &pkt, std::list<Addr> &addresses,
                  std::list<Tick> &delays)
{
    Addr blkAddr = pkt->getAddr() & ~(Addr)(this->blkSize-1);

    for (int d=1; d <= degree; d++) {
        Addr newAddr = blkAddr + d*(this->blkSize);
        if (this->pageStop &&
            (blkAddr & ~(TheISA::VMPageSize - 1)) !=
            (newAddr & ~(TheISA::VMPageSize - 1)))
        {
            //Spanned the page, so now stop
            this->pfSpanPage += degree - d + 1;
            return;
        }
        else
        {
            addresses.push_back(newAddr);
            delays.push_back(latency);
        }
    }
}