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Diffstat (limited to 'src/base/timebuf.hh')
| -rw-r--r-- | src/base/timebuf.hh | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/src/base/timebuf.hh b/src/base/timebuf.hh new file mode 100644 index 000000000..f6b5b2781 --- /dev/null +++ b/src/base/timebuf.hh @@ -0,0 +1,218 @@ +/* + * Copyright (c) 2004-2005 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. + */ + +#ifndef __BASE_TIMEBUF_HH__ +#define __BASE_TIMEBUF_HH__ + +#include <vector> + +template <class T> +class TimeBuffer +{ + protected: + int past; + int future; + int size; + + char *data; + std::vector<char *> index; + int base; + + void valid(int idx) + { + assert (idx >= -past && idx <= future); + } + + public: + friend class wire; + class wire + { + friend class TimeBuffer; + protected: + TimeBuffer<T> *buffer; + int index; + + void set(int idx) + { + buffer->valid(idx); + index = idx; + } + + wire(TimeBuffer<T> *buf, int i) + : buffer(buf), index(i) + { } + + public: + wire() + { } + + wire(const wire &i) + : buffer(i.buffer), index(i.index) + { } + + const wire &operator=(const wire &i) + { + buffer = i.buffer; + set(i.index); + return *this; + } + + const wire &operator=(int idx) + { + set(idx); + return *this; + } + + const wire &operator+=(int offset) + { + set(index + offset); + return *this; + } + + const wire &operator-=(int offset) + { + set(index - offset); + return *this; + } + + wire &operator++() + { + set(index + 1); + return *this; + } + + wire &operator++(int) + { + int i = index; + set(index + 1); + return wire(this, i); + } + + wire &operator--() + { + set(index - 1); + return *this; + } + + wire &operator--(int) + { + int i = index; + set(index - 1); + return wire(this, i); + } + T &operator*() const { return *buffer->access(index); } + T *operator->() const { return buffer->access(index); } + }; + + + public: + TimeBuffer(int p, int f) + : past(p), future(f), size(past + future + 1), + data(new char[size * sizeof(T)]), index(size), base(0) + { + assert(past >= 0 && future >= 0); + char *ptr = data; + for (int i = 0; i < size; i++) { + index[i] = ptr; + memset(ptr, 0, sizeof(T)); + new (ptr) T; + ptr += sizeof(T); + } + } + + TimeBuffer() + : data(NULL) + { + } + + ~TimeBuffer() + { + for (int i = 0; i < size; ++i) + (reinterpret_cast<T *>(index[i]))->~T(); + delete [] data; + } + + void + advance() + { + if (++base >= size) + base = 0; + + int ptr = base + future; + if (ptr >= size) + ptr -= size; + (reinterpret_cast<T *>(index[ptr]))->~T(); + memset(index[ptr], 0, sizeof(T)); + new (index[ptr]) T; + } + + T *access(int idx) + { + //Need more complex math here to calculate index. + valid(idx); + + int vector_index = idx + base; + if (vector_index >= size) { + vector_index -= size; + } else if (vector_index < 0) { + vector_index += size; + } + + return reinterpret_cast<T *>(index[vector_index]); + } + + T &operator[](int idx) + { + //Need more complex math here to calculate index. + valid(idx); + + int vector_index = idx + base; + if (vector_index >= size) { + vector_index -= size; + } else if (vector_index < 0) { + vector_index += size; + } + + return reinterpret_cast<T &>(*index[vector_index]); + } + + wire getWire(int idx) + { + valid(idx); + + return wire(this, idx); + } + + wire zero() + { + return wire(this, 0); + } +}; + +#endif // __BASE_TIMEBUF_HH__ + |