circlebuf.hh (2665:a124942bacb8) | circlebuf.hh (11008:be3b60b52b31) |
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1/* | 1/* |
2 * Copyright (c) 2002-2005 The Regents of The University of Michigan 3 * All rights reserved. | 2 * Copyright (c) 2015 ARM Limited 3 * All rights reserved |
4 * | 4 * |
5 * The license below extends only to copyright in the software and shall 6 * not be construed as granting a license to any other intellectual 7 * property including but not limited to intellectual property relating 8 * to a hardware implementation of the functionality of the software 9 * licensed hereunder. You may use the software subject to the license 10 * terms below provided that you ensure that this notice is replicated 11 * unmodified and in its entirety in all distributions of the software, 12 * modified or unmodified, in source code or in binary form. 13 * |
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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 --- 7 unchanged lines hidden (view full) --- 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 * | 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions are 16 * met: redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer; 18 * redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution; 21 * neither the name of the copyright holders nor the names of its --- 7 unchanged lines hidden (view full) --- 29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 * |
28 * Authors: Nathan Binkert | 37 * Authors: Andreas Sandberg |
29 */ 30 | 38 */ 39 |
31#ifndef __CIRCLEBUF_HH__ 32#define __CIRCLEBUF_HH__ | 40#ifndef __BASE_CIRCLEBUF_HH__ 41#define __BASE_CIRCLEBUF_HH__ |
33 | 42 |
34#include <iosfwd> | 43#include <algorithm> 44#include <cassert> 45#include <vector> |
35 | 46 |
47#include "base/misc.hh" 48#include "sim/serialize.hh" 49 50/** 51 * Circular buffer backed by a vector 52 * 53 * The data in the cricular buffer is stored in a standard 54 * vector. _start designates the first element in the buffer and _stop 55 * points to the last element + 1 (i.e., the position of the next 56 * insertion). The _stop index may be outside the range of the backing 57 * store, which means that the actual index must be calculated as 58 * _stop % capacity. 59 * 60 * Invariants: 61 * <ul> 62 * <li>_start <= _stop 63 * <li>_start < capacity 64 * <li>_stop < 2 * capacity 65 * </ul> 66 */ 67template<typename T> |
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36class CircleBuf 37{ | 68class CircleBuf 69{ |
70 public: 71 typedef T value_type; 72 73 public: 74 explicit CircleBuf(size_t size) 75 : buf(size), _start(0), _stop(0) {} 76 77 /** Is the buffer empty? */ 78 bool empty() const { return _stop == _start; } 79 /** 80 * Return the maximum number of elements that can be stored in 81 * the buffer at any one time. 82 */ 83 size_t capacity() const { return buf.size(); } 84 /** Return the number of elements stored in the buffer. */ 85 size_t size() const { return _stop - _start; } 86 87 /** 88 * Remove all the elements in the buffer. 89 * 90 * Note: This does not actually remove elements from the backing 91 * store. 92 */ 93 void flush() { 94 _start = 0; 95 _stop = 0; 96 } 97 98 /** 99 * Copy buffer contents without advancing the read pointer 100 * 101 * @param out Output iterator/pointer 102 * @param len Number of elements to copy 103 */ 104 template <class OutputIterator> 105 void peek(OutputIterator out, size_t len) const { 106 panic_if(len > size(), 107 "Trying to read past end of circular buffer.\n"); 108 109 if (_start + len <= buf.size()) { 110 std::copy(buf.begin() + _start, 111 buf.begin() + _start + len, 112 out); 113 } else { 114 const size_t head_size(buf.size() - _start); 115 const size_t tail_size(len - head_size); 116 std::copy(buf.begin() + _start, buf.end(), 117 out); 118 std::copy(buf.begin(), buf.begin() + tail_size, 119 out + head_size); 120 } 121 } 122 123 124 /** 125 * Copy buffer contents and advance the read pointer 126 * 127 * @param out Output iterator/pointer 128 * @param len Number of elements to read 129 */ 130 template <class OutputIterator> 131 void read(OutputIterator out, size_t len) { 132 peek(out, len); 133 134 _start += len; 135 normalize(); 136 } 137 138 /** 139 * Add elements to the end of the ring buffers and advance. 140 * 141 * @param in Input iterator/pointer 142 * @param len Number of elements to read 143 */ 144 template <class InputIterator> 145 void write(InputIterator in, size_t len) { 146 // Writes that are larger than the backing store are allowed, 147 // but only the last part of the buffer will be written. 148 if (len > buf.size()) { 149 in += len - buf.size(); 150 len = buf.size(); 151 } 152 153 const size_t next(_stop % buf.size()); 154 const size_t head_len(std::min(buf.size() - next, len)); 155 156 std::copy(in, in + head_len, buf.begin() + next); 157 std::copy(in + head_len, in + len, buf.begin()); 158 159 _stop += len; 160 // We may have written past the old _start pointer. Readjust 161 // the _start pointer to remove the oldest entries in that 162 // case. 163 if (size() > buf.size()) 164 _start = _stop - buf.size(); 165 166 normalize(); 167 } 168 |
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38 protected: | 169 protected: |
39 char *_buf; 40 bool _rollover; 41 int _buflen; 42 int _size; 43 int _start; 44 int _stop; | 170 /** 171 * Normalize the start and stop pointers to ensure that pointer 172 * invariants hold after updates. 173 */ 174 void normalize() { 175 if (_start >= buf.size()) { 176 _stop -= buf.size(); 177 _start -= buf.size(); 178 } |
45 | 179 |
180 assert(_start < buf.size()); 181 assert(_stop < 2 * buf.size()); 182 assert(_start <= _stop); 183 } 184 185 protected: 186 std::vector<value_type> buf; 187 size_t _start; 188 size_t _stop; 189 190}; 191 192 193/** 194 * Simple FIFO implementation backed by a circular buffer. 195 * 196 * This class provides the same basic functionallity as the circular 197 * buffer with the folling differences: 198 * <ul> 199 * <li>Writes are checked to ensure that overflows can't happen. 200 * <li>Unserialization ensures that the data in the checkpoint fits 201 * in the buffer. 202 * </ul> 203 */ 204template<typename T> 205class Fifo 206{ |
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46 public: | 207 public: |
47 explicit CircleBuf(int l); 48 ~CircleBuf(); | 208 typedef T value_type; |
49 | 209 |
50 bool empty() const { return _size == 0; } 51 int size() const { return _size; } 52 void dump(); 53 void flush(); 54 void read(char *b, int len); 55 void read(int fd, int len); 56 void read(int fd); 57 void read(std::ostream &out); 58 void readall(int fd); 59 void write(char b); 60 void write(const char *b); 61 void write(const char *b, int len); | 210 public: 211 Fifo(size_t size) 212 : buf(size) {} 213 214 bool empty() const { return buf.empty(); } 215 size_t size() const { return buf.size(); } 216 size_t capacity() const { return buf.capacity(); } 217 218 void flush() { buf.flush(); } 219 220 template <class OutputIterator> 221 void peek(OutputIterator out, size_t len) const { buf.peek(out, len); } 222 template <class OutputIterator> 223 void read(OutputIterator out, size_t len) { buf.read(out, len); } 224 225 template <class InputIterator> 226 void write(InputIterator in, size_t len) { 227 panic_if(size() + len > capacity(), 228 "Trying to overfill FIFO buffer.\n"); 229 buf.write(in, len); 230 } 231 232 private: 233 CircleBuf<value_type> buf; |
62}; 63 | 234}; 235 |
64#endif // __CIRCLEBUF_HH__ | 236 237template <typename T> 238static void 239arrayParamOut(CheckpointOut &cp, const std::string &name, 240 const CircleBuf<T> ¶m) 241{ 242 std::vector<T> temp(param.size()); 243 param.peek(temp.begin(), temp.size()); 244 arrayParamOut(cp, name, temp); 245} 246 247template <typename T> 248static void 249arrayParamIn(CheckpointIn &cp, const std::string &name, 250 CircleBuf<T> ¶m) 251{ 252 std::vector<T> temp; 253 arrayParamIn(cp, name, temp); 254 255 param.flush(); 256 param.write(temp.cbegin(), temp.size()); 257} 258 259template <typename T> 260static void 261arrayParamOut(CheckpointOut &cp, const std::string &name, 262 const Fifo<T> ¶m) 263{ 264 std::vector<T> temp(param.size()); 265 param.peek(temp.begin(), temp.size()); 266 arrayParamOut(cp, name, temp); 267} 268 269template <typename T> 270static void 271arrayParamIn(CheckpointIn &cp, const std::string &name, 272 Fifo<T> ¶m) 273{ 274 std::vector<T> temp; 275 arrayParamIn(cp, name, temp); 276 277 fatal_if(param.capacity() < temp.size(), 278 "Trying to unserialize data into too small FIFO\n"); 279 280 param.flush(); 281 param.write(temp.cbegin(), temp.size()); 282} 283 284#endif // __BASE_CIRCLEBUF_HH__ |