src/mem/cache/prefetch/tagged_prefetcher_impl.hh

   1 /*
   2  * Copyright (c) 2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Ron Dreslinski
  29  */
  30
  31 /**
  32  * @file
  33  * Describes a tagged prefetcher based on template policies.
  34  */
  35
  36 #include "mem/cache/prefetch/tagged_prefetcher.hh"
  37
  38 template <class TagStore, class Buffering>
  39 TaggedPrefetcher<TagStore, Buffering>::
  40 TaggedPrefetcher(int size, bool pageStop, bool serialSquash,
  41                  bool cacheCheckPush, bool onlyData,
  42                  Tick latency, int degree)
  43     :Prefetcher<TagStore, Buffering>(size, pageStop, serialSquash,
  44                                      cacheCheckPush, onlyData),
  45      latency(latency), degree(degree)
  46 {
  47 }
  48
  49 template <class TagStore, class Buffering>
  50 void
  51 TaggedPrefetcher<TagStore, Buffering>::
  52 calculatePrefetch(Packet * &pkt, std::list<Addr> &addresses,
  53                   std::list<Tick> &delays)
  54 {
  55     Addr blkAddr = pkt->paddr & ~(Addr)(this->blkSize-1);
  56
  57     for (int d=1; d <= degree; d++) {
  58         Addr newAddr = blkAddr + d*(this->blkSize);
  59         if (this->pageStop &&
  60             (blkAddr & ~(TheISA::VMPageSize - 1)) !=
  61             (newAddr & ~(TheISA::VMPageSize - 1)))
  62         {
  63             //Spanned the page, so now stop
  64             this->pfSpanPage += degree - d + 1;
  65             return;
  66         }
  67         else
  68         {
  69             addresses.push_back(newAddr);
  70             delays.push_back(latency);
  71         }
  72     }
  73 }
  74
  75