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diff --git a/base/sched_list.hh b/base/sched_list.hh
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+/*
+ * Copyright (c) 2003 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 SCHED_LIST_HH
+#define SCHED_LIST_HH
+
+#include <list>
+#include "misc.hh"
+
+//  Any types you use this class for must be covered here...
+namespace {
+    void ClearEntry(int &i) { i = 0; };
+    void ClearEntry(unsigned &i) { i = 0; };
+    void ClearEntry(double &i) { i = 0; };
+    template <class T> void ClearEntry(std::list<T> &l) { l.clear(); };
+};
+
+
+//
+//  this is a special list type that allows the user to insert elements at a
+//  specified positive offset from the "current" element, but only allow them
+//  be extracted from the "current" element
+//
+
+
+template <class T>
+class SchedList
+{
+    T *data_array;
+    unsigned position;
+    unsigned size;
+    unsigned mask;
+
+  public:
+    SchedList(unsigned size);
+    SchedList(void);
+
+    void init(unsigned size);
+
+    T &operator[](unsigned offset);
+
+    void advance(void);
+
+    void clear(void);
+};
+
+
+
+//
+//  Constructor
+//
+template<class T>
+SchedList<T>::SchedList(unsigned _size)
+{
+    size = _size;
+
+    //  size must be a power of two
+    if (size & (size-1)) {
+        panic("SchedList: size must be a power of two");
+    }
+
+    if (size < 2) {
+        panic("SchedList: you don't want a list that small");
+    }
+
+    //  calculate the bit mask for the modulo operation
+    mask = size - 1;
+
+    data_array = new T[size];
+
+    if (!data_array) {
+        panic("SchedList: could not allocate memory");
+    }
+
+    clear();
+}
+
+template<class T>
+SchedList<T>::SchedList(void)
+{
+    data_array = 0;
+    size = 0;
+}
+
+
+template<class T> void
+SchedList<T>::init(unsigned _size)
+{
+    size = _size;
+
+    if (!data_array) {
+        //  size must be a power of two
+        if (size & (size-1)) {
+            panic("SchedList: size must be a power of two");
+        }
+
+        if (size < 2) {
+            panic("SchedList: you don't want a list that small");
+        }
+
+        //  calculate the bit mask for the modulo operation
+        mask = size - 1;
+
+        data_array = new T[size];
+
+        if (!data_array) {
+            panic("SchedList: could not allocate memory");
+        }
+
+        clear();
+    }
+}
+
+
+template<class T> void
+SchedList<T>::advance(void)
+{
+    ClearEntry(data_array[position]);
+
+    //    position = (++position % size);
+    position = ++position & mask;
+}
+
+
+template<class T> void
+SchedList<T>::clear(void)
+{
+    for (unsigned i=0; i<size; ++i) {
+        ClearEntry(data_array[i]);
+    }
+
+    position = 0;
+}
+
+
+template<class T>  T&
+SchedList<T>::operator[](unsigned offset)
+{
+    if (offset >= size) {
+        panic("SchedList: can't access element beyond current pointer");
+    }
+
+    //    unsigned p = (position + offset) % size;
+    unsigned p = (position + offset) & mask;
+
+    return data_array[p];
+}
+
+
+
+#endif