summaryrefslogtreecommitdiff
path: root/src/base/timebuf.hh
diff options
context:
space:
mode:
Diffstat (limited to 'src/base/timebuf.hh')
-rw-r--r--src/base/timebuf.hh227
1 files changed, 227 insertions, 0 deletions
diff --git a/src/base/timebuf.hh b/src/base/timebuf.hh
new file mode 100644
index 000000000..1d0de8278
--- /dev/null
+++ b/src/base/timebuf.hh
@@ -0,0 +1,227 @@
+/*
+ * 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.
+ *
+ * Authors: Nathan Binkert
+ * Kevin Lim
+ */
+
+#ifndef __BASE_TIMEBUF_HH__
+#define __BASE_TIMEBUF_HH__
+
+#include <cassert>
+#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);
+ }
+
+ int getSize()
+ {
+ return size;
+ }
+};
+
+#endif // __BASE_TIMEBUF_HH__
+