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+/*
+ * Copyright (c) 2005 The Regents of The University of Michigan
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Ron Dreslinski
+ */
+
+/**
+ * @file
+ * Describes a strided prefetcher based on template policies.
+ */
+
+#ifndef __MEM_CACHE_PREFETCH_STRIDE_PREFETCHER_HH__
+#define __MEM_CACHE_PREFETCH_STRIDE_PREFETCHER_HH__
+
+#include "base/misc.hh" // fatal, panic, and warn
+
+#include "mem/cache/prefetch/prefetcher.hh"
+
+/**
+ * A template-policy based cache. The behavior of the cache can be altered by
+ * supplying different template policies. TagStore handles all tag and data
+ * storage @sa TagStore. Buffering handles all misses and writes/writebacks
+ * @sa MissQueue. Coherence handles all coherence policy details @sa
+ * UniCoherence, SimpleMultiCoherence.
+ */
+template <class TagStore, class Buffering>
+class StridePrefetcher : public Prefetcher<TagStore, Buffering>
+{
+ protected:
+
+ Buffering* mq;
+ TagStore* tags;
+
+ class strideEntry
+ {
+ public:
+ Addr IAddr;
+ Addr MAddr;
+ int stride;
+ int64_t confidence;
+
+/* bool operator < (strideEntry a,strideEntry b)
+ {
+ if (a.confidence == b.confidence) {
+ return true; //??????
+ }
+ else return a.confidence < b.confidence;
+ }*/
+ };
+ Addr* lastMissAddr[64/*MAX_CPUS*/];
+
+ std::list<strideEntry*> table[64/*MAX_CPUS*/];
+ Tick latency;
+ int degree;
+ bool useCPUId;
+
+
+ public:
+
+ StridePrefetcher(int size, bool pageStop, bool serialSquash,
+ bool cacheCheckPush, bool onlyData,
+ Tick latency, int degree, bool useCPUId)
+ :Prefetcher<TagStore, Buffering>(size, pageStop, serialSquash,
+ cacheCheckPush, onlyData),
+ latency(latency), degree(degree), useCPUId(useCPUId)
+ {
+ }
+
+ ~StridePrefetcher() {}
+
+ void calculatePrefetch(Packet * &pkt, std::list<Addr> &addresses,
+ std::list<Tick> &delays)
+ {
+// Addr blkAddr = pkt->paddr & ~(Addr)(this->blkSize-1);
+ int cpuID = pkt->cpu_num;
+ if (!useCPUId) cpuID = 0;
+
+ /* Scan Table for IAddr Match */
+/* std::list<strideEntry*>::iterator iter;
+ for (iter=table[cpuID].begin();
+ iter !=table[cpuID].end();
+ iter++) {
+ if ((*iter)->IAddr == pkt->pc) break;
+ }
+
+ if (iter != table[cpuID].end()) {
+ //Hit in table
+
+ int newStride = blkAddr - (*iter)->MAddr;
+ if (newStride == (*iter)->stride) {
+ (*iter)->confidence++;
+ }
+ else {
+ (*iter)->stride = newStride;
+ (*iter)->confidence--;
+ }
+
+ (*iter)->MAddr = blkAddr;
+
+ for (int d=1; d <= degree; d++) {
+ Addr newAddr = blkAddr + d * newStride;
+ 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);
+ }
+ }
+ }
+ else {
+ //Miss in table
+ //Find lowest confidence and replace
+
+ }
+*/ }
+};
+
+#endif // __MEM_CACHE_PREFETCH_STRIDE_PREFETCHER_HH__