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 "arch/isa_traits.hh"
  37 #include "mem/cache/prefetch/tagged_prefetcher.hh"
  38
  39 template <class TagStore, class Buffering>
  40 TaggedPrefetcher<TagStore, Buffering>::
  41 TaggedPrefetcher(int size, bool pageStop, bool serialSquash,
  42                  bool cacheCheckPush, bool onlyData,
  43                  Tick latency, int degree)
  44     :Prefetcher<TagStore, Buffering>(size, pageStop, serialSquash,
  45                                      cacheCheckPush, onlyData),
  46      latency(latency), degree(degree)
  47 {
  48 }
  49
  50 template <class TagStore, class Buffering>
  51 void
  52 TaggedPrefetcher<TagStore, Buffering>::
  53 calculatePrefetch(Packet * &pkt, std::list<Addr> &addresses,
  54                   std::list<Tick> &delays)
  55 {
  56     Addr blkAddr = pkt->getAddr() & ~(Addr)(this->blkSize-1);
  57
  58     for (int d=1; d <= degree; d++) {
  59         Addr newAddr = blkAddr + d*(this->blkSize);
  60         if (this->pageStop &&
  61             (blkAddr & ~(TheISA::VMPageSize - 1)) !=
  62             (newAddr & ~(TheISA::VMPageSize - 1)))
  63         {
  64             //Spanned the page, so now stop
  65             this->pfSpanPage += degree - d + 1;
  66             return;
  67         }
  68         else
  69         {
  70             addresses.push_back(newAddr);
  71             delays.push_back(latency);
  72         }
  73     }
  74 }
  75
  76