1/* 2 * Copyright (c) 2015,2017-2018 ARM Limited 3 * All rights reserved 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 * 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 22 * contributors may be used to endorse or promote products derived from 23 * this software without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 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 * 37 * Authors: Andreas Sandberg 38 */ 39 40#ifndef __BASE_CIRCLEBUF_HH__ 41#define __BASE_CIRCLEBUF_HH__ 42 43#include <algorithm> 44#include <cassert> 45#include <vector> 46 47#include "base/circular_queue.hh" 48#include "base/logging.hh" 49#include "sim/serialize.hh" 50 51/** 52 * Circular buffer backed by a vector though a CircularQueue. 53 * 54 * The data in the cricular buffer is stored in a standard 55 * vector. 56 * 57 */ 58template<typename T> 59class CircleBuf : public CircularQueue<T> 60{ 61 public: 62 explicit CircleBuf(size_t size) 63 : CircularQueue<T>(size) {} 64 using CircularQueue<T>::empty; 65 using CircularQueue<T>::size; 66 using CircularQueue<T>::capacity; 67 using CircularQueue<T>::begin; 68 using CircularQueue<T>::end; 69 using CircularQueue<T>::pop_front; 70 using CircularQueue<T>::advance_tail; 71 72 /** 73 * Copy buffer contents without advancing the read pointer 74 * 75 * @param out Output iterator/pointer 76 * @param len Number of elements to copy 77 */ 78 template <class OutputIterator> 79 void peek(OutputIterator out, size_t len) const { 80 peek(out, 0, len); 81 } 82 83 /** 84 * Copy buffer contents without advancing the read pointer 85 * 86 * @param out Output iterator/pointer 87 * @param offset Offset into the ring buffer 88 * @param len Number of elements to copy 89 */ 90 template <class OutputIterator> 91 void peek(OutputIterator out, off_t offset, size_t len) const { 92 panic_if(offset + len > size(), 93 "Trying to read past end of circular buffer.\n"); 94 95 std::copy(begin() + offset, begin() + offset + len, out); 96 } 97 98 /** 99 * Copy buffer contents and advance the read pointer 100 * 101 * @param out Output iterator/pointer 102 * @param len Number of elements to read 103 */ 104 template <class OutputIterator> 105 void read(OutputIterator out, size_t len) { 106 peek(out, len); 107 pop_front(len); 108 } 109 110 /** 111 * Add elements to the end of the ring buffers and advance. 112 * 113 * @param in Input iterator/pointer 114 * @param len Number of elements to read 115 */ 116 template <class InputIterator> 117 void write(InputIterator in, size_t len) { 118 // Writes that are larger than the backing store are allowed, 119 // but only the last part of the buffer will be written. 120 if (len > capacity()) { 121 in += len - capacity(); 122 len = capacity(); 123 } 124 125 std::copy(in, in + len, end()); 126 advance_tail(len); 127 } 128}; 129 130/** 131 * Simple FIFO implementation backed by a circular buffer. 132 * 133 * This class provides the same basic functionallity as the circular 134 * buffer with the folling differences: 135 * <ul> 136 * <li>Writes are checked to ensure that overflows can't happen. 137 * <li>Unserialization ensures that the data in the checkpoint fits 138 * in the buffer. 139 * </ul> 140 */ 141template<typename T> 142class Fifo 143{ 144 public: 145 typedef T value_type; 146 147 public: 148 Fifo(size_t size) 149 : buf(size) {} 150 151 bool empty() const { return buf.empty(); } 152 size_t size() const { return buf.size(); } 153 size_t capacity() const { return buf.capacity(); } 154 155 void flush() { buf.flush(); } 156 157 template <class OutputIterator> 158 void peek(OutputIterator out, size_t len) const { buf.peek(out, len); } 159 template <class OutputIterator> 160 void read(OutputIterator out, size_t len) { buf.read(out, len); } 161 162 template <class InputIterator> 163 void write(InputIterator in, size_t len) { 164 panic_if(size() + len > capacity(), 165 "Trying to overfill FIFO buffer.\n"); 166 buf.write(in, len); 167 } 168 169 private: 170 CircleBuf<value_type> buf; 171}; 172 173 174template <typename T> 175void 176arrayParamOut(CheckpointOut &cp, const std::string &name, 177 const CircleBuf<T> ¶m) 178{ 179 std::vector<T> temp(param.size()); 180 param.peek(temp.begin(), temp.size()); 181 arrayParamOut(cp, name, temp); 182} 183 184template <typename T> 185void 186arrayParamIn(CheckpointIn &cp, const std::string &name, 187 CircleBuf<T> ¶m) 188{ 189 std::vector<T> temp; 190 arrayParamIn(cp, name, temp); 191 192 param.flush(); 193 param.write(temp.cbegin(), temp.size()); 194} 195 196template <typename T> 197void 198arrayParamOut(CheckpointOut &cp, const std::string &name, 199 const Fifo<T> ¶m) 200{ 201 std::vector<T> temp(param.size()); 202 param.peek(temp.begin(), temp.size()); 203 arrayParamOut(cp, name, temp); 204} 205 206template <typename T> 207void 208arrayParamIn(CheckpointIn &cp, const std::string &name, 209 Fifo<T> ¶m) 210{ 211 std::vector<T> temp; 212 arrayParamIn(cp, name, temp); 213 214 fatal_if(param.capacity() < temp.size(), 215 "Trying to unserialize data into too small FIFO\n"); 216 217 param.flush(); 218 param.write(temp.cbegin(), temp.size()); 219} 220 221#endif // __BASE_CIRCLEBUF_HH__ 222