PerfectCacheMemory.hh revision 11020
1/* 2 * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood 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 29#ifndef __MEM_RUBY_STRUCTURES_PERFECTCACHEMEMORY_HH__ 30#define __MEM_RUBY_STRUCTURES_PERFECTCACHEMEMORY_HH__ 31 32#include "base/hashmap.hh" 33#include "mem/protocol/AccessPermission.hh" 34#include "mem/ruby/common/Address.hh" 35 36template<class ENTRY> 37struct PerfectCacheLineState 38{ 39 PerfectCacheLineState() { m_permission = AccessPermission_NUM; } 40 AccessPermission m_permission; 41 ENTRY m_entry; 42}; 43 44template<class ENTRY> 45inline std::ostream& 46operator<<(std::ostream& out, const PerfectCacheLineState<ENTRY>& obj) 47{ 48 return out; 49} 50 51template<class ENTRY> 52class PerfectCacheMemory 53{ 54 public: 55 PerfectCacheMemory(); 56 57 // tests to see if an address is present in the cache 58 bool isTagPresent(const Address& address) const; 59 60 // Returns true if there is: 61 // a) a tag match on this address or there is 62 // b) an Invalid line in the same cache "way" 63 bool cacheAvail(const Address& address) const; 64 65 // find an Invalid entry and sets the tag appropriate for the address 66 void allocate(const Address& address); 67 68 void deallocate(const Address& address); 69 70 // Returns with the physical address of the conflicting cache line 71 Address cacheProbe(const Address& newAddress) const; 72 73 // looks an address up in the cache 74 ENTRY* lookup(const Address& address); 75 const ENTRY* lookup(const Address& address) const; 76 77 // Get/Set permission of cache block 78 AccessPermission getPermission(const Address& address) const; 79 void changePermission(const Address& address, AccessPermission new_perm); 80 81 // Print cache contents 82 void print(std::ostream& out) const; 83 84 private: 85 // Private copy constructor and assignment operator 86 PerfectCacheMemory(const PerfectCacheMemory& obj); 87 PerfectCacheMemory& operator=(const PerfectCacheMemory& obj); 88 89 // Data Members (m_prefix) 90 m5::hash_map<Address, PerfectCacheLineState<ENTRY> > m_map; 91}; 92 93template<class ENTRY> 94inline std::ostream& 95operator<<(std::ostream& out, const PerfectCacheMemory<ENTRY>& obj) 96{ 97 obj.print(out); 98 out << std::flush; 99 return out; 100} 101 102template<class ENTRY> 103inline 104PerfectCacheMemory<ENTRY>::PerfectCacheMemory() 105{ 106} 107 108// tests to see if an address is present in the cache 109template<class ENTRY> 110inline bool 111PerfectCacheMemory<ENTRY>::isTagPresent(const Address& address) const 112{ 113 return m_map.count(line_address(address)) > 0; 114} 115 116template<class ENTRY> 117inline bool 118PerfectCacheMemory<ENTRY>::cacheAvail(const Address& address) const 119{ 120 return true; 121} 122 123// find an Invalid or already allocated entry and sets the tag 124// appropriate for the address 125template<class ENTRY> 126inline void 127PerfectCacheMemory<ENTRY>::allocate(const Address& address) 128{ 129 PerfectCacheLineState<ENTRY> line_state; 130 line_state.m_permission = AccessPermission_Invalid; 131 line_state.m_entry = ENTRY(); 132 m_map[line_address(address)] = line_state; 133} 134 135// deallocate entry 136template<class ENTRY> 137inline void 138PerfectCacheMemory<ENTRY>::deallocate(const Address& address) 139{ 140 m_map.erase(line_address(address)); 141} 142 143// Returns with the physical address of the conflicting cache line 144template<class ENTRY> 145inline Address 146PerfectCacheMemory<ENTRY>::cacheProbe(const Address& newAddress) const 147{ 148 panic("cacheProbe called in perfect cache"); 149 return newAddress; 150} 151 152// looks an address up in the cache 153template<class ENTRY> 154inline ENTRY* 155PerfectCacheMemory<ENTRY>::lookup(const Address& address) 156{ 157 return &m_map[line_address(address)].m_entry; 158} 159 160// looks an address up in the cache 161template<class ENTRY> 162inline const ENTRY* 163PerfectCacheMemory<ENTRY>::lookup(const Address& address) const 164{ 165 return &m_map[line_address(address)].m_entry; 166} 167 168template<class ENTRY> 169inline AccessPermission 170PerfectCacheMemory<ENTRY>::getPermission(const Address& address) const 171{ 172 return m_map[line_address(address)].m_permission; 173} 174 175template<class ENTRY> 176inline void 177PerfectCacheMemory<ENTRY>::changePermission(const Address& address, 178 AccessPermission new_perm) 179{ 180 Address line_address = address; 181 line_address.makeLineAddress(); 182 PerfectCacheLineState<ENTRY>& line_state = m_map[line_address]; 183 line_state.m_permission = new_perm; 184} 185 186template<class ENTRY> 187inline void 188PerfectCacheMemory<ENTRY>::print(std::ostream& out) const 189{ 190} 191 192#endif // __MEM_RUBY_STRUCTURES_PERFECTCACHEMEMORY_HH__ 193