stride.hh revision 5875
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 strided prefetcher. 34 */ 35 36#ifndef __MEM_CACHE_PREFETCH_STRIDE_PREFETCHER_HH__ 37#define __MEM_CACHE_PREFETCH_STRIDE_PREFETCHER_HH__ 38 39#include <limits.h> 40#include "mem/cache/prefetch/base.hh" 41 42class StridePrefetcher : public BasePrefetcher 43{ 44 protected: 45 46 static const int Max_Contexts = 64; 47 48 // These constants need to be changed with the type of the 49 // 'confidence' field below. 50 static const int Max_Conf = INT_MAX; 51 static const int Min_Conf = INT_MIN; 52 53 class StrideEntry 54 { 55 public: 56 Addr instAddr; 57 Addr missAddr; 58 int stride; 59 int confidence; 60 }; 61 62 Addr *lastMissAddr[Max_Contexts]; 63 64 std::list<StrideEntry*> table[Max_Contexts]; 65 Tick latency; 66 int degree; 67 bool useContextId; 68 69 public: 70 71 StridePrefetcher(const BaseCacheParams *p) 72 : BasePrefetcher(p), latency(p->prefetch_latency), 73 degree(p->prefetch_degree), useContextId(p->prefetch_use_cpu_id) 74 { 75 } 76 77 ~StridePrefetcher() {} 78 79 void calculatePrefetch(PacketPtr &pkt, std::list<Addr> &addresses, 80 std::list<Tick> &delays); 81}; 82 83#endif // __MEM_CACHE_PREFETCH_STRIDE_PREFETCHER_HH__ 84